exercise-induced myogenic precursor: Topics by WorldWideScience.org

Sample records for exercise-induced myogenic precursor

Irisin is a pro-myogenic factor that induces skeletal muscle hypertrophy and rescues denervation-induced atrophy.

Science.gov (United States)

Reza, Musarrat Maisha; Subramaniyam, Nathiya; Sim, Chu Ming; Ge, Xiaojia; Sathiakumar, Durgalakshmi; McFarlane, Craig; Sharma, Mridula; Kambadur, Ravi

2017-10-24

Exercise induces expression of the myokine irisin, which is known to promote browning of white adipose tissue and has been shown to mediate beneficial effects following exercise. Here we show that irisin induces expression of a number of pro-myogenic and exercise response genes in myotubes. Irisin increases myogenic differentiation and myoblast fusion via activation of IL6 signaling. Injection of irisin in mice induces significant hypertrophy and enhances grip strength of uninjured muscle. Following skeletal muscle injury, irisin injection improves regeneration and induces hypertrophy. The effects of irisin on hypertrophy are due to activation of satellite cells and enhanced protein synthesis. In addition, irisin injection rescues loss of skeletal muscle mass following denervation by enhancing satellite cell activation and reducing protein degradation. These data suggest that irisin functions as a pro-myogenic factor in mice.
Differentially activated macrophages orchestrate myogenic precursor cell fate during human skeletal muscle regeneration

DEFF Research Database (Denmark)

Saclier, Marielle; Yacoub-Youssef, Houda; Mackey, Abigail

2013-01-01

, we explored both in vitro and in vivo, in human, the interactions of differentially activated MPs with myogenic precursor cells (MPCs) during adult myogenesis and skeletal muscle regeneration. We showed in vitro that through the differential secretion of cytokines and growth factors, proinflammatory...... anti-inflammatory markers. These data demonstrate for the first time in human that MPs sequentially orchestrate adult myogenesis during regeneration of damaged skeletal muscle. These results support the emerging concept that inflammation, through MP activation, controls stem cell fate and coordinates......Macrophages (MPs) exert either beneficial or deleterious effects on tissue repair, depending on their activation/polarization state. They are crucial for adult skeletal muscle repair, notably by acting on myogenic precursor cells. However, these interactions have not been fully characterized. Here...
Derivation of Skeletal Myogenic Precursors from Human Pluripotent Stem Cells Using Conditional Expression of PAX7.

Science.gov (United States)

Darabi, Radbod; Perlingeiro, Rita C R

2016-01-01

Cell-based therapies are considered as one of the most promising approaches for the treatment of degenerating pathologies including muscle disorders and dystrophies. Advances in the approach of reprogramming somatic cells into induced pluripotent stem (iPS) cells allow for the possibility of using the patient's own pluripotent cells to generate specific tissues for autologous transplantation. In addition, patient-specific tissue derivatives have been shown to represent valuable material for disease modeling and drug discovery. Nevertheless, directed differentiation of pluripotent stem cells into a specific lineage is not a trivial task especially in the case of skeletal myogenesis, which is generally poorly recapitulated during the in vitro differentiation of pluripotent stem cells.Here, we describe a practical and efficient method for the derivation of skeletal myogenic precursors from differentiating human pluripotent stem cells using controlled expression of PAX7. Flow cytometry (FACS) purified myogenic precursors can be expanded exponentially and differentiated in vitro into myotubes, enabling researchers to use these cells for disease modeling as well as therapeutic purposes.
A new pro-migratory activity on human myogenic precursor cells for a synthetic peptide within the E domain of the mechano growth factor

International Nuclear Information System (INIS)

Mills, Philippe; Lafreniere, Jean-Francois; Benabdallah, Basma Fattouma; El Fahime, El Mostafa; Tremblay, Jacques-P.

2007-01-01

Duchenne muscular dystrophy (DMD) is an inherited disease that leads to progressive muscle wasting. Myogenic precursor cell transplantation is an approach that can introduce the normal dystrophin gene in the muscle fibers of the patients. Unfortunately, these myogenic precursor cells do not migrate well in the muscle and thus many injections have to be done to enable a good graft success. Recent reports have shown that there is extensive splicing of the IGF-1 gene in muscles. The MGF isoform contains a C-terminal 24 amino acids peptide in the E domain (MGF-Ct24E) that has intrinsic properties. It can promote the proliferation while delaying the differentiation of C 2 C 12 cells. Here, we demonstrated that this synthetic peptide is a motogenic factor for human precursor myogenic cells in vitro and in vivo. Indeed, MGF-Ct24E peptide can modulate members of the fibrinolytic and metalloproteinase systems, which are implicated in the migration of myogenic cells. MGF-Ct24E peptide enhances the expression of u-PA, u-PAR and MMP-7 while reducing PAI-1 activity. Moreover, it has no effect on the gelatinases MMP-2 and -9. Those combined effects can favour cell migration. Finally, we present some results suggesting that the MGF-Ct24E peptide induces these cell responses through a mechanism that does not involve the IGF-1 receptor. Thus, this MGF-Ct24E peptide has a new pro-migratory activity on human myogenic precursor cells that may be helpful in the treatment of DMD. Those results reinforce the possibility that the IGF-1Ec isoform may produce an E domain peptide that can act as a cytokine
Reduced satellite cell numbers and myogenic capacity in aging can be alleviated by endurance exercise.

Directory of Open Access Journals (Sweden)

Gabi Shefer

2010-10-01

Full Text Available Muscle regeneration depends on satellite cells, myogenic stem cells that reside on the myofiber surface. Reduced numbers and/or decreased myogenic aptitude of these cells may impede proper maintenance and contribute to the age-associated decline in muscle mass and repair capacity. Endurance exercise was shown to improve muscle performance; however, the direct impact on satellite cells in aging was not yet thoroughly determined. Here, we focused on characterizing the effect of moderate-intensity endurance exercise on satellite cell, as possible means to attenuate adverse effects of aging. Young and old rats of both genders underwent 13 weeks of treadmill-running or remained sedentary.Gastrocnemius muscles were assessed for the effect of age, gender and exercise on satellite-cell numbers and myogenic capacity. Satellite cells were identified in freshly isolated myofibers based on Pax7 immunostaining (i.e., ex-vivo. The capacity of individual myofiber-associated cells to produce myogenic progeny was determined in clonal assays (in-vitro. We show an age-associated decrease in satellite-cell numbers and in the percent of myogenic clones in old sedentary rats. Upon exercise, there was an increase in myofibers that contain higher numbers of satellite cells in both young and old rats, and an increase in the percent of myogenic clones derived from old rats. Changes at the satellite cell level in old rats were accompanied with positive effects on the lean-to-fat Gast muscle composition and on spontaneous locomotion levels. The significance of these data is that they suggest that the endurance exercise-mediated boost in both satellite numbers and myogenic properties may improve myofiber maintenance in aging.
GH mediates exercise-dependent activation of SVZ neural precursor cells in aged mice.

Directory of Open Access Journals (Sweden)

Daniel G Blackmore

Full Text Available Here we demonstrate, both in vivo and in vitro, that growth hormone (GH mediates precursor cell activation in the subventricular zone (SVZ of the aged (12-month-old brain following exercise, and that GH signaling stimulates precursor activation to a similar extent to exercise. Our results reveal that both addition of GH in culture and direct intracerebroventricular infusion of GH stimulate neural precursor cells in the aged brain. In contrast, no increase in neurosphere numbers was observed in GH receptor null animals following exercise. Continuous infusion of a GH antagonist into the lateral ventricle of wild-type animals completely abolished the exercise-induced increase in neural precursor cell number. Given that the aged brain does not recover well after injury, we investigated the direct effect of exercise and GH on neural precursor cell activation following irradiation. This revealed that physical exercise as well as infusion of GH promoted repopulation of neural precursor cells in irradiated aged animals. Conversely, infusion of a GH antagonist during exercise prevented recovery of precursor cells in the SVZ following irradiation.
GH Mediates Exercise-Dependent Activation of SVZ Neural Precursor Cells in Aged Mice

Science.gov (United States)

Blackmore, Daniel G.; Vukovic, Jana; Waters, Michael J.; Bartlett, Perry F.

2012-01-01

Here we demonstrate, both in vivo and in vitro, that growth hormone (GH) mediates precursor cell activation in the subventricular zone (SVZ) of the aged (12-month-old) brain following exercise, and that GH signaling stimulates precursor activation to a similar extent to exercise. Our results reveal that both addition of GH in culture and direct intracerebroventricular infusion of GH stimulate neural precursor cells in the aged brain. In contrast, no increase in neurosphere numbers was observed in GH receptor null animals following exercise. Continuous infusion of a GH antagonist into the lateral ventricle of wild-type animals completely abolished the exercise-induced increase in neural precursor cell number. Given that the aged brain does not recover well after injury, we investigated the direct effect of exercise and GH on neural precursor cell activation following irradiation. This revealed that physical exercise as well as infusion of GH promoted repopulation of neural precursor cells in irradiated aged animals. Conversely, infusion of a GH antagonist during exercise prevented recovery of precursor cells in the SVZ following irradiation. PMID:23209615
Myogenic Precursors from iPS Cells for Skeletal Muscle Cell Replacement Therapy

Directory of Open Access Journals (Sweden)

Isart Roca

2015-01-01

Full Text Available The use of adult myogenic stem cells as a cell therapy for skeletal muscle regeneration has been attempted for decades, with only moderate success. Myogenic progenitors (MP made from induced pluripotent stem cells (iPSCs are promising candidates for stem cell therapy to regenerate skeletal muscle since they allow allogenic transplantation, can be produced in large quantities, and, as compared to adult myoblasts, present more embryonic-like features and more proliferative capacity in vitro, which indicates a potential for more self-renewal and regenerative capacity in vivo. Different approaches have been described to make myogenic progenitors either by gene overexpression or by directed differentiation through culture conditions, and several myopathies have already been modeled using iPSC-MP. However, even though results in animal models have shown improvement from previous work with isolated adult myoblasts, major challenges regarding host response have to be addressed and clinically relevant transplantation protocols are lacking. Despite these challenges we are closer than we think to bringing iPSC-MP towards clinical use for treating human muscle disease and sporting injuries.
Comparison exercise of probabilistic precursor analysis

International Nuclear Information System (INIS)

Fauchille, V.; Babst, S.

2004-01-01

From 2000 up to 2003, a comparison exercise concerning accident precursor programs was performed by IRSN, GRS, and NUPEC (Japan). The objective of this exercise was to compare the methodologies used to quantify conditional core damage probability related to incidents which can be considered as accident precursors. This exercise provided interesting results concerning the interpretation of such events. Generally, the participants identified similar scenarios of potential degradation. However, for several dominant sequences, differences in the results were noticed. The differences can be attributed to variations in the plant design, the strategy of management and in the methodological approach. For many reasons, comparison of human reliability analysis was difficult and perhaps another exercise in the future could provide more information about this subject. On the other hand, interesting outcomes have been obtained from the quantification of both common cause failures and potential common cause failures. (orig.)
N-cadherin and integrin blockade inhibit arteriolar myogenic reactivity but not pressure-induced increases in intracellular Ca2+

Directory of Open Access Journals (Sweden)

Teresa Y. Jackson

2010-12-01

Full Text Available The vascular myogenic response is characterized by arterial constriction in response to an increase in intraluminal pressure and dilatation to a decrease in pressure. This mechanism is important for the regulation of blood flow, capillary pressure and arterial pressure. The identity of the mechanosensory mechanism(s for this response is incompletely understood but has been shown to include the integrins as cell-extracellular matrix receptors. The possibility that a cell-cell adhesion receptor is involved has not been studied. Thus, we tested the hypothesis that N-cadherin, a cell-cell adhesion molecule in vascular smooth muscle cells (VSMCs, was important for myogenic responsiveness. The purpose of this study was to investigate:
1. whether cadherin inhibition blocks myogenic responses to increases in intraluminal pressure and 2. the effect of the cadherin or integrin blockade on pressure-induced changes in [Ca2+]i. Cadherin blockade was tested in isolated rat cremaster arterioles on myogenic responses to acute pressure steps from 60 – 100 mmHg and changes in VSMC Ca2+ were measured using fura-2. In the presence of a synthetic cadherin inhibitory peptide or a function blocking antibody, myogenic responses were inhibited. In contrast, during N-cadherin blockade, pressure-induced changes in [Ca2+]i were not altered. Similarly, vessels treated with function-blocking β1- or β3-integrin antibodies maintained pressure-induced [Ca2+]i responses despite inhibition of myogenic constriction. Collectively, these data suggest that both cadherins and integrins play a fundamental role in mediating myogenic constriction but argue against their direct involvement in mediating pressure-induced [Ca2+]i increases.
Microglia modulate hippocampal neural precursor activity in response to exercise and aging.

Science.gov (United States)

Vukovic, Jana; Colditz, Michael J; Blackmore, Daniel G; Ruitenberg, Marc J; Bartlett, Perry F

2012-05-09

Exercise has been shown to positively augment adult hippocampal neurogenesis; however, the cellular and molecular pathways mediating this effect remain largely unknown. Previous studies have suggested that microglia may have the ability to differentially instruct neurogenesis in the adult brain. Here, we used transgenic Csf1r-GFP mice to investigate whether hippocampal microglia directly influence the activation of neural precursor cells. Our results revealed that an exercise-induced increase in neural precursor cell activity was mediated via endogenous microglia and abolished when these cells were selectively removed from hippocampal cultures. Conversely, microglia from the hippocampi of animals that had exercised were able to activate latent neural precursor cells when added to neurosphere preparations from sedentary mice. We also investigated the role of CX(3)CL1, a chemokine that is known to provide a more neuroprotective microglial phenotype. Intraparenchymal infusion of a blocking antibody against the CX(3)CL1 receptor, CX(3)CR1, but not control IgG, dramatically reduced the neurosphere formation frequency in mice that had exercised. While an increase in soluble CX(3)CL1 was observed following running, reduced levels of this chemokine were found in the aged brain. Lower levels of CX(3)CL1 with advancing age correlated with the natural decline in neural precursor cell activity, a state that could be partially alleviated through removal of microglia. These findings provide the first direct evidence that endogenous microglia can exert a dual and opposing influence on neural precursor cell activity within the hippocampus, and that signaling through the CX(3)CL1-CX(3)CR1 axis critically contributes toward this process.
Magic-factor 1, a partial agonist of Met, induces muscle hypertrophy by protecting myogenic progenitors from apoptosis.

Directory of Open Access Journals (Sweden)

Marco Cassano

2008-09-01

Full Text Available Hepatocyte Growth Factor (HGF is a pleiotropic cytokine of mesenchymal origin that mediates a characteristic array of biological activities including cell proliferation, survival, motility and morphogenesis. Its high affinity receptor, the tyrosine kinase Met, is expressed by a wide range of tissues and can be activated by either paracrine or autocrine stimulation. Adult myogenic precursor cells, the so called satellite cells, express both HGF and Met. Following muscle injury, autocrine HGF-Met stimulation plays a key role in promoting activation and early division of satellite cells, but is shut off in a second phase to allow myogenic differentiation. In culture, HGF stimulation promotes proliferation of muscle precursors thereby inhibiting their differentiation.Magic-Factor 1 (Met-Activating Genetically Improved Chimeric Factor-1 or Magic-F1 is an HGF-derived, engineered protein that contains two Met-binding domains repeated in tandem. It has a reduced affinity for Met and, in contrast to HGF it elicits activation of the AKT but not the ERK signaling pathway. As a result, Magic-F1 is not mitogenic but conserves the ability to promote cell survival. Here we show that Magic-F1 protects myogenic precursors against apoptosis, thus increasing their fusion ability and enhancing muscular differentiation. Electrotransfer of Magic-F1 gene into adult mice promoted muscular hypertrophy and decreased myocyte apoptosis. Magic-F1 transgenic mice displayed constitutive muscular hypertrophy, improved running performance and accelerated muscle regeneration following injury. Crossing of Magic-F1 transgenic mice with alpha-sarcoglycan knock-out mice -a mouse model of muscular dystrophy- or adenovirus-mediated Magic-F1 gene delivery resulted in amelioration of the dystrophic phenotype as measured by both anatomical/histological analysis and functional tests.Because of these features Magic-F1 represents a novel molecular tool to counteract muscle wasting in major
Bone morphogenic protein-2 regulates the myogenic differentiation of PMVECs in CBDL rat serum-induced pulmonary microvascular remodeling

Energy Technology Data Exchange (ETDEWEB)

Liu, Chang; Chen, Lin; Zeng, Jing; Cui, Jian; Ning, Jiao-nin [Department of Anesthesia, Southwest Hospital, The Third Military Medical University, Chongqing 400038 (China); Wang, Guan-song [Institute of Respiratory Disease, Xinqiao Hospital, The Third Military Medical University, Chongqing 400037 (China); Belguise, Karine; Wang, Xiaobo [Université P. Sabatier Toulouse III and CNRS, LBCMCP, 31062 Toulouse Cedex 9 (France); Qian, Gui-sheng [Institute of Respiratory Disease, Xinqiao Hospital, The Third Military Medical University, Chongqing 400037 (China); Lu, Kai-zhi [Department of Anesthesia, Southwest Hospital, The Third Military Medical University, Chongqing 400038 (China); Yi, Bin, E-mail: yibin1974@163.com [Department of Anesthesia, Southwest Hospital, The Third Military Medical University, Chongqing 400038 (China)

2015-08-01

Hepatopulmonary syndrome (HPS) is characterized by an arterial oxygenation defect induced by intrapulmonary vasodilation (IPVD) that increases morbidity and mortality. In our previous study, it was determined that both the proliferation and the myogenic differentiation of pulmonary microvascular endothelial cells (PMVECs) play a key role in the development of IPVD. However, the molecular mechanism underlying the relationship between IPVD and the myogenic differentiation of PMVECs remains unknown. Additionally, it has been shown that bone morphogenic protein-2 (BMP2), via the control of protein expression, may regulate cell differentiation including cardiomyocyte differentiation, neuronal differentiation and odontoblastic differentiation. In this study, we observed that common bile duct ligation (CBDL)-rat serum induced the upregulation of the expression of several myogenic proteins (SM-α-actin, calponin, SM-MHC) and enhanced the expression levels of BMP2 mRNA and protein in PMVECs. We also observed that both the expression levels of Smad1/5 and the activation of phosphorylated Smad1/5 were significantly elevated in PMVECs following exposure to CBDL-rat serum, which was accompanied by the down-regulation of Smurf1. The blockage of the BMP2/Smad signaling pathway with Noggin inhibited the myogenic differentiation of PMVECs, a process that was associated with relatively low expression levels of both SM-α-actin and calponin in the setting of CBDL-rat serum exposure, although SM-MHC expression was not affected. These findings suggested that the BMP2/Smad signaling pathway is involved in the myogenic differentiation of the PMVECs. In conclusion, our data highlight the pivotal role of BMP2 in the CBDL-rat serum-induced myogenic differentiation of PMVECs via the activation of both Smad1 and Smad5 and the down-regulation of Smurf1, which may represent a potential therapy for HPS-induced pulmonary vascular remodeling. - Highlights: • CBDL-rat serum promotes the myogenic
Inhibition of glycogen synthase kinase-3β attenuates glucocorticoid-induced suppression of myogenic differentiation in vitro.

Directory of Open Access Journals (Sweden)

Zhenyu Ma

Full Text Available Glucocorticoids are the only therapy that has been demonstrated to alter the progress of Duchenne muscular dystrophy (DMD, the most common muscular dystrophy in children. However, glucocorticoids disturb skeletal muscle metabolism and hamper myogenesis and muscle regeneration. The mechanisms involved in the glucocorticoid-mediated suppression of myogenic differentiation are not fully understood. Glycogen synthase kinase-3β (GSK-3β is considered to play a central role as a negative regulator in myogenic differentiation. Here, we showed that glucocorticoid treatment during the first 48 h in differentiation medium decreased the level of phosphorylated Ser9-GSK-3β, an inactive form of GSK-3β, suggesting that glucocorticoids affect GSK-3β activity. We then investigated whether GSK-3β inhibition could regulate glucocorticoid-mediated suppression of myogenic differentiation in vitro. Two methods were employed to inhibit GSK-3β: pharmacological inhibition with LiCl and GSK-3β gene knockdown. We found that both methods resulted in enhanced myotube formation and increased levels of muscle regulatory factors and muscle-specific protein expression. Importantly, GSK-3β inhibition attenuated glucocorticoid-induced suppression of myogenic differentiation. Collectively, these data suggest the involvement of GSK-3β in the glucocorticoid-mediated impairment of myogenic differentiation. Therefore, the inhibition of GSK-3β may be a strategy for preventing glucocorticoid-induced muscle degeneration.
Sparing of extraocular muscle in aging and muscular dystrophies: A myogenic precursor cell hypothesis

Energy Technology Data Exchange (ETDEWEB)

Kallestad, Kristen M.; Hebert, Sadie L.; McDonald, Abby A.; Daniel, Mark L.; Cu, Sharon R.; McLoon, Linda K., E-mail: mcloo001@tc.umn.edu

2011-04-01

The extraocular muscles (EOM) are spared from pathology in aging and many forms of muscular dystrophy. Despite many studies, this sparing remains an enigma. The EOM have a distinct embryonic lineage compared to somite-derived muscles, and we have shown that they continuously remodel throughout life, maintaining a population of activated satellite cells even in aging. These data suggested the hypothesis that there is a population of myogenic precursor cells (mpcs) in EOM that is different from those in limb, with either elevated numbers of stem cells and/or mpcs with superior proliferative capacity compared to mpcs in limb. Using flow cytometry, EOM and limb muscle mononuclear cells were compared, and a number of differences were seen. Using two different cell isolation methods, EOM have significantly more mpcs per mg muscle than limb skeletal muscle. One specific subpopulation significantly increased in EOM compared to limb was positive for CD34 and negative for Sca-1, M-cadherin, CD31, and CD45. We named these the EOMCD34 cells. Similar percentages of EOMCD34 cells were present in both newborn EOM and limb muscle. They were retained in aged EOM, whereas the population decreased significantly in adult limb muscle and were extremely scarce in aged limb muscle. Most importantly, the percentage of EOMCD34 cells was elevated in the EOM from both the mdx and the mdx/utrophin{sup -/-} (DKO) mouse models of DMD and extremely scarce in the limb muscles of these mice. In vitro, the EOMCD34 cells had myogenic potential, forming myotubes in differentiation media. After determining a media better able to induce proliferation in these cells, a fusion index was calculated. The cells isolated from EOM had a 40% higher fusion index compared to the same cells isolated from limb muscle. The EOMCD34 cells were resistant to both oxidative stress and mechanical injury. These data support our hypothesis that the EOM may be spared in aging and in muscular dystrophies due to a
Sparing of extraocular muscle in aging and muscular dystrophies: A myogenic precursor cell hypothesis

International Nuclear Information System (INIS)

Kallestad, Kristen M.; Hebert, Sadie L.; McDonald, Abby A.; Daniel, Mark L.; Cu, Sharon R.; McLoon, Linda K.

2011-01-01

The extraocular muscles (EOM) are spared from pathology in aging and many forms of muscular dystrophy. Despite many studies, this sparing remains an enigma. The EOM have a distinct embryonic lineage compared to somite-derived muscles, and we have shown that they continuously remodel throughout life, maintaining a population of activated satellite cells even in aging. These data suggested the hypothesis that there is a population of myogenic precursor cells (mpcs) in EOM that is different from those in limb, with either elevated numbers of stem cells and/or mpcs with superior proliferative capacity compared to mpcs in limb. Using flow cytometry, EOM and limb muscle mononuclear cells were compared, and a number of differences were seen. Using two different cell isolation methods, EOM have significantly more mpcs per mg muscle than limb skeletal muscle. One specific subpopulation significantly increased in EOM compared to limb was positive for CD34 and negative for Sca-1, M-cadherin, CD31, and CD45. We named these the EOMCD34 cells. Similar percentages of EOMCD34 cells were present in both newborn EOM and limb muscle. They were retained in aged EOM, whereas the population decreased significantly in adult limb muscle and were extremely scarce in aged limb muscle. Most importantly, the percentage of EOMCD34 cells was elevated in the EOM from both the mdx and the mdx/utrophin -/- (DKO) mouse models of DMD and extremely scarce in the limb muscles of these mice. In vitro, the EOMCD34 cells had myogenic potential, forming myotubes in differentiation media. After determining a media better able to induce proliferation in these cells, a fusion index was calculated. The cells isolated from EOM had a 40% higher fusion index compared to the same cells isolated from limb muscle. The EOMCD34 cells were resistant to both oxidative stress and mechanical injury. These data support our hypothesis that the EOM may be spared in aging and in muscular dystrophies due to a subpopulation of
Skeletal Muscle Estrogen Receptor Activation in Response to Eccentric Exercise Up-Regulates Myogenic-Related Gene Expression Independent of Differing Serum Estradiol Levels Occurring during the Human Menstrual Cycle.

Science.gov (United States)

Haines, Mackenzie; McKinley-Barnard, Sarah K; Andre, Thomas L; Gann, Josh J; Hwang, Paul S; Willoughby, Darryn S

2018-03-01

This study sought to determine if the differences in serum estradiol we have previously observed to occur during the mid-follicular (MF) and mid-luteal (ML) phases of the female menstrual cycle could be attributed to estrogen-induced receptor activation and subsequent effects on myogenic-related genes which may otherwise impact muscle regeneration in response to eccentric exercise. Twenty-two physically-active females (20.9 ± 1.4 years, 63.5 ± 9.0 kg, 1.65 ± 0.08 m) underwent an eccentric exercise bout of the knee extensors during the MF and ML phases of their 28-day menstrual cycle. Prior to (PRE), at 6 (6HRPOST), and 24 (24HRPOST) hours post-exercise for each session, participants had muscle biopsies obtained. Skeletal muscle estradiol and estrogen receptor-α (ER-α) content and ER-DNA binding were determined with ELISA. Real-time PCR was used to assess ER-α, Myo-D, and cyclin D1 mRNA expression. Data were analyzed utilizing a 2 x 3 repeated measures univariate analyses of variance (ANOVA) for each criterion variable (p ≤ .05). Skeletal muscle estradiol levels were not significantly impacted by either menstrual phase (p > 0.05); however, both ER-α mRNA and protein were significantly increased during MF (p < 0.05). ER-DNA binding and Myo-D mRNA expression increased significantly in both menstrual phases in response to exercise but were not different from one another; however, cyclin D1 mRNA expression was significantly greater during MF. This study demonstrates that skeletal muscle ER-α activation in response to eccentric exercise up-regulates myogenic-related gene expression independent of serum estradiol levels occurring during the human menstrual cycle.
Retained Myogenic Potency of Human Satellite Cells from Torn Rotator Cuff Muscles Despite Fatty Infiltration.

Science.gov (United States)

Koide, Masashi; Hagiwara, Yoshihiro; Tsuchiya, Masahiro; Kanzaki, Makoto; Hatakeyama, Hiroyasu; Tanaka, Yukinori; Minowa, Takashi; Takemura, Taro; Ando, Akira; Sekiguchi, Takuya; Yabe, Yutaka; Itoi, Eiji

2018-01-01

Rotator cuff tears (RCTs) are a common shoulder problem in the elderly that can lead to both muscle atrophy and fatty infiltration due to less physical load. Satellite cells, quiescent cells under the basal lamina of skeletal muscle fibers, play a major role in muscle regeneration. However, the myogenic potency of human satellite cells in muscles with fatty infiltration is unclear due to the difficulty in isolating from small samples, and the mechanism of the progression of fatty infiltration has not been elucidated. The purpose of this study was to analyze the population of myogenic and adipogenic cells in disused supraspinatus (SSP) and intact subscapularis (SSC) muscles of the RCTs from the same patients using fluorescence-activated cell sorting. The microstructure of the muscle with fatty infiltration was observed as a whole mount condition under multi-photon microscopy. Myogenic differentiation potential and gene expression were evaluated in satellite cells. The results showed that the SSP muscle with greater fatty infiltration surrounded by collagen fibers compared with the SSC muscle under multi-photon microscopy. A positive correlation was observed between the ratio of muscle volume to fat volume and the ratio of myogenic precursor to adipogenic precursor. Although no difference was observed in the myogenic potential between the two groups in cell culture, satellite cells in the disused SSP muscle showed higher intrinsic myogenic gene expression than those in the intact SSC muscle. Our results indicate that satellite cells from the disused SSP retain sufficient potential of muscle growth despite the fatty infiltration.
Loss of MyoD and Myf5 in Skeletal Muscle Stem Cells Results in Altered Myogenic Programming and Failed Regeneration

Directory of Open Access Journals (Sweden)

Masakazu Yamamoto

2018-03-01

Full Text Available Summary: MyoD and Myf5 are fundamental regulators of skeletal muscle lineage determination in the embryo, and their expression is induced in satellite cells following muscle injury. MyoD and Myf5 are also expressed by satellite cell precursors developmentally, although the relative contribution of historical and injury-induced expression to satellite cell function is unknown. We show that satellite cells lacking both MyoD and Myf5 (double knockout [dKO] are maintained with aging in uninjured muscle. However, injured muscle fails to regenerate and dKO satellite cell progeny accumulate in damaged muscle but do not undergo muscle differentiation. dKO satellite cell progeny continue to express markers of myoblast identity, although their myogenic programming is labile, as demonstrated by dramatic morphological changes and increased propensity for non-myogenic differentiation. These data demonstrate an absolute requirement for either MyoD or Myf5 in muscle regeneration and indicate that their expression after injury stabilizes myogenic identity and confers the capacity for muscle differentiation. : In this article, Goldhamer and colleagues show that loss of both MyoD and Myf5 in skeletal muscle satellite cells results in regenerative failure following injury. Satellite cell progeny accumulate in injured muscle and continue to express markers of myoblast identity, but do not undergo muscle differentiation, and exhibit a propensity for non-myogenic differentiation. Keywords: skeletal muscle regeneration, muscle stem cell programming, muscle differentiation, satellite cell, MyoD, Myf5, adipogenesis, fibrosis, conditional knockout, Cre/loxP
Exercise-Induced Asthma

Science.gov (United States)

... Videos for Educators Search English Español Exercise-Induced Asthma KidsHealth / For Parents / Exercise-Induced Asthma What's in ... Exercise-Induced Asthma Print What Is Exercise-Induced Asthma? Most kids and teens with asthma have symptoms ...

Interleukin-4 improves the migration of human myogenic precursor cells in vitro and in vivo

International Nuclear Information System (INIS)

Lafreniere, J.F.; Mills, P.; Bouchentouf, M.; Tremblay, J.P.

2006-01-01

Different molecules are available to recruit new neighboring myogenic cells to the site of regeneration. Formerly called B cell stimulatory factor-1, IL-4 can now be included in the list of motogenic factors. The present report demonstrates that human IL-4 is not required for fusion between mononucleated myoblasts but is required for myotube maturation. In identifying IL-4 as a pro-migratory agent for myogenic cells, these results provide a mechanism which partly explains IL-4 demonstrated activity during differentiation. Among the different mechanisms by which IL-4 might enhance myoblast migration processes, our results indicate that there are implications of some integrins and of three major components of the fibrinolytic system. Indeed, increases in the amount of active urokinase plasminogen activator and its receptor were observed following an IL-4 treatment, while the plasminogen activator inhibitor-1 decreased. Finally, IL-4 did not modify the amount of cell surface α5 integrin but increased the presence of β3 and β1 integrins. This integrin modulation might favor myogenic cell migration and its interaction with newly formed myotubes. Therefore, IL-4 co-injection with transplanted myoblasts might be an approach to enhance the migration of transplanted cells for the treatment of a damaged myocardium or of a Duchenne Muscular Dystrophy patient
The Effect of Resistance Exercise on Inflammatory and Myogenic Markers in Patients with Chronic Kidney Disease

Directory of Open Access Journals (Sweden)

Emma L. Watson

2017-07-01

Full Text Available Background: Muscle wasting is a common complication of Chronic Kidney Disease (CKD and is clinically important given its strong association with morbidity and mortality in many other chronic conditions. Exercise provides physiological benefits for CKD patients, however the molecular response to exercise remains to be fully determined. We investigated the inflammatory and molecular response to resistance exercise before and after training in these patients.Methods: This is a secondary analysis of a randomized trial that investigated the effect of 8 week progressive resistance training on muscle mass and strength compared to non-exercising controls. A sub-set of the cohort consented to vastus lateralis skeletal muscle biopsies (n = 10 exercise, n = 7 control in which the inflammatory response (IL-6, IL-15, MCP-1 TNF-α, myogenic (MyoD, myogenin, myostatin, anabolic (P-Akt, P-eEf2 and catabolic events (MuRF-1, MAFbx, 14 kDa, ubiquitin conjugates and overall levels of oxidative stress have been studied.Results: A large inflammatory response to unaccustomed exercise was seen with IL-6, MCP-1, and TNF-α all significantly elevated from baseline by 53-fold (P < 0.001, 25-fold (P < 0.001, and 4-fold (P < 0.001, respectively. This response was reduced following training with IL-6, MCP-1, and TNF-α elevated non-significantly by 2-fold (P = 0.46, 2.4-fold (P = 0.19, and 2.5-fold (P = 0.06, respectively. In the untrained condition, an acute bout of resistance exercise did not result in increased phosphorylation of Akt (P = 0.84, but this was restored following training (P = 0.01. Neither unaccustomed nor accustomed exercise resulted in a change in myogenin or MyoD mRNA expression (P = 0.88, P = 0.90, respectively. There was no evidence that resistance exercise training created a prolonged oxidative stress response within the muscle, or increased catabolism.Conclusions: Unaccustomed exercise creates a large inflammatory response within the muscle, which is
Impaired myogenic tone in mesenteric arteries from overweight rats

Directory of Open Access Journals (Sweden)

Sweazea Karen L

2012-03-01

Full Text Available Abstract Background Rats fed high fat (HFD or high sucrose (HSD diets develop increased adiposity as well as impaired vasodilatory responsiveness stemming from oxidative stress. Moreover, HFD rats become hypertensive compared to either control (Chow or HSD fed rats, suggesting elevated vascular tone. We hypothesized that rats with increased adiposity and oxidative stress demonstrate augmented pressure-induced vasoconstriction (i.e. myogenic tone that could account for the hypertensive state. Methods Male Sprague-Dawley rats were fed Chow, HFD or HSD for 6 weeks. The effects of oxidative stress and endogenous nitric oxide on myogenic responses were examined in small mesenteric arteries by exposing the arteries to incremental intraluminal pressure steps in the presence of antioxidants or an inhibitor of nitric oxide synthase, LNNA (100 μM. Results Contrary to the hypothesis, rats fed either HSD or HFD had significantly impaired myogenic responses despite similar vascular morphology and passive diameter responses to increasing pressures. Vascular smooth muscle (VSM calcium levels were normal in HFD arteries suggesting that diminished calcium sensitivity was responsible for the impaired myogenic response. In contrast, VSM calcium levels were reduced in HSD arteries but were increased with pre-exposure of arteries to the antioxidants tiron (10 mM and catalase (1200 U/mL, also resulting in enhanced myogenic tone. These findings show that oxidative stress impairs myogenic tone in arteries from HSD rats by decreasing VSM calcium. Similarly, VSM calcium responses were increased in arteries from HFD rats following treatment with tiron and catalase, but this did not result in improved myogenic tone. Nitric oxide is involved in the impaired myogenic response in HFD, but not HSD, rats since inhibition with LNNA resulted in maximal myogenic responses at lower intraluminal pressures and VSM calcium levels, further implicating reduced calcium sensitivity in
CD36 is required for myoblast fusion during myogenic differentiation

International Nuclear Information System (INIS)

Park, Seung-Yoon; Yun, Youngeun; Kim, In-San

2012-01-01

Highlights: ► CD36 expression was induced during myogenic differentiation. ► CD36 expression was localized in multinucleated myotubes. ► The expression of myogenic markers is attenuated in CD36 knockdown C2C12 cells. ► Knockdown of CD36 significantly inhibited myotube formation during differentiation. -- Abstract: Recently, CD36 has been found to be involved in the cytokine-induced fusion of macrophage. Myoblast fusion to form multinucleated myotubes is required for myogenesis and muscle regeneration. Because a search of gene expression database revealed the attenuation of CD36 expression in the muscles of muscular dystrophy patients, the possibility that CD36 could be required for myoblast fusion was investigated. CD36 expression was markedly up-regulated during myoblast differentiation and localized in multinucleated myotubes. Knockdown of endogenous CD36 significantly decreased the expression of myogenic markers as well as myotube formation. These results support the notion that CD36 plays an important role in cell fusion during myogenic differentiation. Our finding will aid the elucidation of the common mechanism governing cell-to-cell fusion in various fusion models.
CD36 is required for myoblast fusion during myogenic differentiation

Energy Technology Data Exchange (ETDEWEB)

Park, Seung-Yoon [Department of Biochemistry, College of Medicine, Dongguk University and Medical Institute of Dongguk University, Gyeongju 780-714 (Korea, Republic of); Yun, Youngeun [Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Kim, In-San, E-mail: iskim@knu.ac.kr [Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Biomedical Research Institute, Korea Institute Science and Technology, Seoul (Korea, Republic of)

2012-11-02

Highlights: Black-Right-Pointing-Pointer CD36 expression was induced during myogenic differentiation. Black-Right-Pointing-Pointer CD36 expression was localized in multinucleated myotubes. Black-Right-Pointing-Pointer The expression of myogenic markers is attenuated in CD36 knockdown C2C12 cells. Black-Right-Pointing-Pointer Knockdown of CD36 significantly inhibited myotube formation during differentiation. -- Abstract: Recently, CD36 has been found to be involved in the cytokine-induced fusion of macrophage. Myoblast fusion to form multinucleated myotubes is required for myogenesis and muscle regeneration. Because a search of gene expression database revealed the attenuation of CD36 expression in the muscles of muscular dystrophy patients, the possibility that CD36 could be required for myoblast fusion was investigated. CD36 expression was markedly up-regulated during myoblast differentiation and localized in multinucleated myotubes. Knockdown of endogenous CD36 significantly decreased the expression of myogenic markers as well as myotube formation. These results support the notion that CD36 plays an important role in cell fusion during myogenic differentiation. Our finding will aid the elucidation of the common mechanism governing cell-to-cell fusion in various fusion models.
Exercise-Induced Bronchoconstriction (EIB)

Science.gov (United States)

... Conditions & Treatments ▸ Conditions Dictionary ▸ Exercise-Induced Bronchoconstriction Share | Exercise-Induced Bronchoconstriction (EIB) « Back to A to Z Listing Exercise-Induced Bronchoconstriction, (EIB), often known as exercise-induced ...
Serum Proteases Potentiate BMP-Induced Cell Cycle Re-entry of Dedifferentiating Muscle Cells during Newt Limb Regeneration

NARCIS (Netherlands)

Wagner, Ines; Wang, Heng; Weissert, Philipp M.; Straube, Werner L.; Shevchenko, Anna; Gentzel, Marc; Brito, Goncalo; Tazaki, Akira; Oliveira, Catarina; Sugiura, Takuji; Shevchenko, Andrej; Simon, Andras; Drechsel, David N.; Tanaka, Elly M.

2017-01-01

Limb amputation in the newt induces myofibers to dedifferentiate and re-enter the cell cycle to generate proliferative myogenic precursors in the regeneration blastema. Here we show that bone morphogenetic proteins (BMPs) and mature BMPs that have been further cleaved by serum proteases induce cell
Muscle Contraction Induces Acute Hydroxymethylation of the Exercise-Responsive Gene Nr4a3

DEFF Research Database (Denmark)

Pattamaprapanont, Pattarawan; Garde, Christian; Fabre, Odile

2016-01-01

stimulated over time is required to determine whether contraction-induced demethylation is preceded by changes in the hydroxymethylcytosine level. Here, we established an acute skeletal muscle contraction model to mimic the effects of acute exercise on gene expression. We used this model to investigate...... promoters. Exercise induces dynamic DNA demethylation at gene promoters; however, the contribution of the demethylation precursor hydroxymethylcytosine is unknown. Given the evanescent nature of hydroxymethylcytosine, a muscle contraction model that allows for the collection of samples that are repeatedly...... the effect of muscle contraction on DNA demethylation and hydroxymethylation. First, we performed an acute exercise study in healthy humans to identify an exercise-responsive gene that we could study in culture. We identified the nuclear receptor subfamily 4 group A member 3 (Nr4a3) gene with the highest...
Opposite roles of MRF4 and MyoD in cell proliferation and myogenic differentiation

International Nuclear Information System (INIS)

Jin Xun; Kim, Jong-Gun; Oh, Myung-Joo; Oh, Ho-Yeon; Sohn, Young-Woo; Pian, Xumin; Yin, Jin Long; Beck, Samuel; Lee, Namkyung; Son, Jeesoo; Kim, Hyunggee; Yan Changguo; Wang Jihui; Choi, Yun-Jaie; Whang, Kwang Youn

2007-01-01

The basic helix-loop-helix myogenic regulatory factors play critical roles in skeletal myogenesis. Among the myogenic regulatory factors (MRFs), MRF4 shows a biphasic expression pattern during the formation of myotomes, although its function remains unclear. In this study, we used BEF (spontaneously immortalized bovine embryonic fibroblast that shows myogenic differentiation by overexpression of MyoD) and C2C12 cells to investigate the function of MRF4. Ectopic expressions of MRF4 did not stimulate myogenic differentiation in the BEF and C2C12 cells, but did show a marked increase of cell proliferation, upregulation of cyclin E, and downregulation of p21 WAF1 . Furthermore, MRF4 was found to induce degradation of the MyoD protein, which acts as a transcriptional activator for p21 WAF1 , and thus indicates that MRF4 accelerates cell proliferation by suppressing MyoD-dependent p21 WAF1 expression. However, forced expression of MyoD in the MRF4-overexpressing cells inhibited cell proliferation and partially induced myogenic differentiation, which suggests that MyoD is a potential negative intercessor of MRF4 in the regulation of the cell cycle. Taken together, these results indicate that MRF4 and MyoD play competitive roles in myogenesis by stimulating cell proliferation and differentiation, respectively
Local myogenic pulp-derived cell injection enhances craniofacial muscle regeneration in vivo.

Science.gov (United States)

Jung, J E; Song, M J; Shin, S; Choi, Y J; Kim, K H; Chung, C J

2017-02-01

To enhance myogenic differentiation in pulp cells isolated from extracted premolars by epigenetic modification using a DNA demethylation agent, 5-aza-2'-deoxycytidine (5-Aza), and to evaluate the potent stimulatory effect of 5-Aza-treated pulp cell injection for craniofacial muscle regeneration in vivo. Pulp cells were isolated from premolars extracted for orthodontic purposes from four adults (age range, 18-22.1 years). Levels of myogenic differentiation and functional contraction response in vitro were compared between pulp cells with or without pre-treatment of 5-Aza. Changes in muscle regeneration in response to green fluorescent protein (GFP)-labelled myogenic pulp cell injection in vivo were evaluated using a cardiotoxin (CTX)-induced muscle injury model of the gastrocnemius as well as the masseter muscle in mice. Pre-treatment of 5-Aza in pulp cells stimulated myotube formation, myogenic differentiation in terms of desmin and myogenin expression, and the level of collagen gel contraction. The local injection of 5-Aza pre-treated myogenic pulp cells was engrafted into the host tissue and indicated signs of enhanced muscle regeneration in both the gastrocnemius and the masseter muscles. The epigenetic modification of pulp cells from extracted premolars and the local injection of myogenic pulp cells may stimulate craniofacial muscles regeneration in vivo. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Exercise-induced rhabdomyolysis.

Science.gov (United States)

Lee, George

2014-11-03

Exercise-induced rhabdomyolysis, or exertional rhabdomyolysis (ER), is a clinical entity typically considered when someone presents with muscle stiffness, swelling, and pain out of proportion to the expected fatigue post exercise. The diagnosis is confirmed by myoglobinuria, and an elevated serum Creatinine Phosphokinase (CPK) level, usually 10 times the normal range. However, an elevation in CPK is seen in most forms of strenuous exercise, up to 20 times the upper normal range. Therefore, there is no definitive pathologic CPK cut-off. Fortunately the dreaded complication of acute renal failure is rare compared to other forms rhabdomyolysis. We review the risks, diagnosis, clinical course and treatment for exercise- induced rhabdomyolysis.
Prevalence of exercise-induced bronchoconstriction and exercise-induced laryngeal obstruction in a general adolescent population.

Science.gov (United States)

Johansson, Henrik; Norlander, Katarina; Berglund, Lars; Janson, Christer; Malinovschi, Andrei; Nordvall, Lennart; Nordang, Leif; Emtner, Margareta

2015-01-01

Exercise-induced respiratory symptoms are common among adolescents. Exercise is a known stimulus for transient narrowing of the airways, such as exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO). Our aim was to investigate the prevalence of EIB and EILO in a general population of adolescents. In this cross-sectional study, a questionnaire on exercise-induced dyspnoea was sent to all adolescents born in 1997 and 1998 in Uppsala, Sweden (n=3838). A random subsample of 146 adolescents (99 with self-reported exercise-induced dyspnoea and 47 without this condition) underwent standardised treadmill exercise tests for EIB and EILO. The exercise test for EIB was performed while breathing dry air; a positive test was defined as a decrease of ≥10% in FEV1 from baseline. EILO was investigated using continuous laryngoscopy during exercise. The estimated prevalence of EIB and EILO in the total population was 19.2% and 5.7%, respectively. No gender differences were found. In adolescents with exercise-induced dyspnoea, 39.8% had EIB, 6% had EILO and 4.8% had both conditions. In this group, significantly more boys than girls had neither EIB nor EILO (64.7% vs 38.8%; p=0.026). There were no significant differences in body mass index, lung function, diagnosed asthma or medication between the participants with exercise-induced dyspnoea who had or did not have a positive EIB or EILO test result. Both EIB and EILO are common causes of exercise-induced dyspnoea in adolescents. EILO is equally common among girls and boys and can coexist with EIB. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Community effect triggers terminal differentiation of myogenic cells derived from muscle satellite cells by quenching Smad signaling

Energy Technology Data Exchange (ETDEWEB)

Yanagisawa, Michiko [Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Oobu, Aichi 474-8522 (Japan); Aging Research, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550 (Japan); Mukai, Atsushi; Shiomi, Kosuke [Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Oobu, Aichi 474-8522 (Japan); Song, Si-Yong [Institute of Neuroscience, Faculty of Pharmaceutical Sciences at Kagawa, Tokushima Bunri University, 1314-1 Shido, Sanuki-shi, Kagawa 769-2193 (Japan); Hashimoto, Naohiro, E-mail: nao@ncgg.go.jp [Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Oobu, Aichi 474-8522 (Japan)

2011-01-15

A high concentration of bone morphogenetic proteins (BMPs) stimulates myogenic progenitor cells to undergo heterotopic osteogenic differentiation. However, the physiological role of the Smad signaling pathway during terminal muscle differentiation has not been resolved. We report here that Smad1/5/8 was phosphorylated and activated in undifferentiated growing mouse myogenic progenitor Ric10 cells without exposure to any exogenous BMPs. The amount of phosphorylated Smad1/5/8 was severely reduced during precocious myogenic differentiation under the high cell density culture condition even in growth medium supplemented with a high concentration of serum. Inhibition of the Smad signaling pathway by dorsomorphin, an inhibitor of Smad activation, or noggin, a specific antagonist of BMP, induced precocious terminal differentiation of myogenic progenitor cells in a cell density-dependent fashion even in growth medium. In addition, Smad1/5/8 was transiently activated in proliferating myogenic progenitor cells during muscle regeneration in rats. The present results indicate that the Smad signaling pathway is involved in a critical switch between growth and differentiation of myogenic progenitor cells both in vitro and in vivo. Furthermore, precocious cell density-dependent myogenic differentiation suggests that a community effect triggers the terminal muscle differentiation of myogenic cells by quenching the Smad signaling.
Community effect triggers terminal differentiation of myogenic cells derived from muscle satellite cells by quenching Smad signaling

International Nuclear Information System (INIS)

Yanagisawa, Michiko; Mukai, Atsushi; Shiomi, Kosuke; Song, Si-Yong; Hashimoto, Naohiro

2011-01-01

A high concentration of bone morphogenetic proteins (BMPs) stimulates myogenic progenitor cells to undergo heterotopic osteogenic differentiation. However, the physiological role of the Smad signaling pathway during terminal muscle differentiation has not been resolved. We report here that Smad1/5/8 was phosphorylated and activated in undifferentiated growing mouse myogenic progenitor Ric10 cells without exposure to any exogenous BMPs. The amount of phosphorylated Smad1/5/8 was severely reduced during precocious myogenic differentiation under the high cell density culture condition even in growth medium supplemented with a high concentration of serum. Inhibition of the Smad signaling pathway by dorsomorphin, an inhibitor of Smad activation, or noggin, a specific antagonist of BMP, induced precocious terminal differentiation of myogenic progenitor cells in a cell density-dependent fashion even in growth medium. In addition, Smad1/5/8 was transiently activated in proliferating myogenic progenitor cells during muscle regeneration in rats. The present results indicate that the Smad signaling pathway is involved in a critical switch between growth and differentiation of myogenic progenitor cells both in vitro and in vivo. Furthermore, precocious cell density-dependent myogenic differentiation suggests that a community effect triggers the terminal muscle differentiation of myogenic cells by quenching the Smad signaling.
Use of post-exercise laryngoscopy to evaluate exercise induced dyspnea.

LENUS (Irish Health Repository)

McNally, P

2010-10-01

We present the case of a child with asthma who continued to have marked exercise induced dyspnea despite appropriate treatment, and in the face of adequate control of all other asthma symptoms. Spirometry showed a marked truncation of inspiratory flow, and laryngoscopy performed immediately after exercise showed laryngomalacia with dynamic, partial inspiratory obstruction. Exercise induced laryngomalacia (EIL) is a rare cause of exercise induced dyspnea which is diagnosed by post exercise flexible laryngoscopy and may require supraglottoplasty.
Immortalization of human myogenic progenitor cell clone retaining multipotentiality

International Nuclear Information System (INIS)

Hashimoto, Naohiro; Kiyono, Tohru; Wada, Michiko R.; Shimizu, Shirabe; Yasumoto, Shigeru; Inagawa, Masayo

2006-01-01

Human myogenic cells have limited ability to proliferate in culture. Although forced expression of telomerase can immortalize some cell types, telomerase alone delays senescence of human primary cultured myogenic cells, but fails to immortalize them. In contrast, constitutive expression of both telomerase and the E7 gene from human papillomavirus type 16 immortalizes primary human myogenic cells. We have established an immortalized primary human myogenic cell line preserving multipotentiality by ectopic expression of telomerase and E7. The immortalized human myogenic cells exhibit the phenotypic characteristics of their primary parent, including an ability to undergo myogenic, osteogenic, and adipogenic terminal differentiation under appropriate culture conditions. The immortalized cells will be useful for both basic and applied studies aimed at human muscle disorders. Furthermore, immortalization by transduction of telomerase and E7 represents a useful method by which to expand human myogenic cells in vitro without compromising their ability to differentiate
Head to head comparison of short-term treatment with the NAD+ precursor nicotinamide mononucleotide (NMN and six weeks of exercise in obese female mice

Directory of Open Access Journals (Sweden)

Golam Mezbah Uddin

2016-08-01

Full Text Available Obesity is well known to be a major cause of several chronic metabolic diseases, which can be partially counteracted by exercise. This is due, in part, to an upregulation of mitochondrial activity through increased nicotinamide adenine dinucleotide (NAD+. Recent studies have shown that NAD+ levels can be increased by using the NAD+ precursor, nicotinamide mononucleotide (NMN leading to the suggestion that NMN could be a useful intervention in diet related metabolic disorders. In this study we compared the metabolic, and especially mitochondrial-associated, effects of exercise and NMN in ameliorating the consequences of high-fat diet (HFD induced obesity in mice. Sixty female 5 week old C57BL6/J mice were allocated across 5 interventions: Chow sedentary: CS; Chow exercise: CEX; HFD sedentary: HS; HFD NMN: HNMN; HFD exercise: HEX (12/group. After 6 weeks of diet, exercise groups underwent treadmill exercise (15 m/min for 45 minutes, 6 days per week for 6 weeks. NMN or vehicle (500 mg/kg body weight was injected (i.p. daily for the last 17 days. No significant alteration in body weight was observed in response to exercise or NMN. The HFD significantly altered adiposity, glucose tolerance, plasma insulin, NADH levels and citrate synthase activity in muscle and liver. HEX and HNMN groups both showed significantly improved glucose tolerance compared to the HS group. NAD+ levels were increased significantly both in muscle and liver by NMN whereas exercise increased NAD+ only in muscle. Both NMN and exercise ameliorated the HFD-induced reduction in liver citrate synthase activity. However, exercise, but not NMN, ameliorated citrate synthase activity in muscle. Overall these data suggest that while exercise and NMN-supplementation can induce similar reversal of the glucose intolerance induced by obesity, they are associated with tissue-specific effects and differential alterations to mitochondrial function in muscle and liver.
FSHD myoblasts fail to downregulate intermediate filament protein vimentin during myogenic differentiation.

Directory of Open Access Journals (Sweden)

Lipinski M.

2011-10-01

Full Text Available Facioscapulohumeral muscular dystrophy (FSHD is an autosomal dominant hereditary neuromuscular disorder. The clinical features of FSHD include weakness of the facial and shoulder girdle muscles followed by wasting of skeletal muscles of the pelvic girdle and lower extremities. Although FSHD myoblasts grown in vitro can be induced to differentiate into myotubes by serum starvation, the resulting FSHD myotubes have been shown previously to be morphologically abnormal. Aim. In order to find the cause of morphological anomalies of FSHD myotubes we compared in vitro myogenic differentiation of normal and FSHD myoblasts at the protein level. Methods. We induced myogenic differentiation of normal and FSHD myoblasts by serum starvation. We then compared protein extracts from proliferating myoblasts and differentiated myotubes using SDS-PAGE followed by mass spectrometry identification of differentially expressed proteins. Results. We demonstrated that the expression of vimentin was elevated at the protein and mRNA levels in FSHD myotubes as compared to normal myotubes. Conclusions. We demonstrate for the first time that in contrast to normal myoblasts, FSHD myoblasts fail to downregulate vimentin after induction of in vitro myogenic differentiation. We suggest that vimentin could be an easily detectable marker of FSHD myotubes
Research progress of exercise-induced fatigue

Directory of Open Access Journals (Sweden)

Peng-yi DAI

2016-12-01

Full Text Available Exercise-induced fatigue is a comprehensive response to a variety of physiological and biochemical changes in the body, and can affect people's quality of life to different extents. If no timely recovery after occurrence of fatigue, accumulated gradually, it can lead to "burnout", a "overtraining syndrome", "chronic fatigue syndrome", etc., which will cause endocrine disturbance, immune suppression, even physical illness. Exercise-induced fatigue becomes an important factor endangering human health. In recent years, many experts and scholars at home and abroad are committed to the research of exercise-induced fatigue, and have put forward a variety of hypothesis to explain the cause of exercise-induced fatigue. They expect to find out the methods for preventing and eliminating exercise-induced fatigue. This article discusses mainly the pathogenesis, model building, elimination/ relief, etc. of exercise-induced fatigue to point out the research achievements of exercise-induced fatigue and its existing problems. DOI: 10.11855/j.issn.0577-7402.2016.11.14
Clone-derived human AF-amniotic fluid stem cells are capable of skeletal myogenic differentiation in vitro and in vivo.

Science.gov (United States)

Ma, Xiaorong; Zhang, Shengli; Zhou, Junmei; Chen, Baisong; Shang, Yafeng; Gao, Tongbing; Wang, Xue; Xie, Hua; Chen, Fang

2012-08-01

Stem cell-based therapy may be the most promising method to cure skeletal muscle degenerative diseases such as Duchenne muscular dystrophy (DMD) and trauma in the future. Human amniotic fluid is enriched with early-stage stem cells from developing fetuses and these cells have cardiomyogenic potential both in vitro and in vivo. In the present study, we investigated the characteristics of human amniotic fluid-derived AF-type stem (HAF-AFS) cells by flow cytometry, immunofluorescence staining, reverse-transcription polymerase chain reaction, and osteogenic and adipogenic differentiation analysis. After confirming the stemness of HAF-AFS cells, we tested whether HAF-AFS cells could differentiate into skeletal myogenic cells in vitro and incorporate into regenerating skeletal muscle in vivo. By temporary exposure to the DNA demethylation agent 5-aza-2'-deoxycytidine (5-Aza dC) or co-cultured with C2C12 myoblasts, HAF-AFS cells differentiated into skeletal myogenic cells, expressing skeletal myogenic cell-specific markers such as Desmin, Troponin I (Tn I) and α-Actinin. Four weeks after transplantation into cardiotoxin-injured and X-ray-irradiated tibialis anterior (TA) muscles of NOD/SCID mice, HAF-AFS cells survived, differentiated into myogenic precursor cells and fused with host myofibres. The findings that HAF-AFS cells differentiate into myogenic cells in vitro and incorporate in skeletal muscle regeneration in vivo hold the promise of HAF-AFS cell-based therapy for skeletal muscle degenerative diseases. Copyright © 2012 John Wiley & Sons, Ltd.

Exercise alters myostatin protein expression in sedentary and exercised streptozotocin-diabetic rats.

Science.gov (United States)

Bassi, Daniela; Bueno, Patricia de Godoy; Nonaka, Keico Okino; Selistre-Araujo, Heloisa Sobreiro; Leal, Angela Merice de Oliveira

2015-04-01

The aim of this study was to analyze the effect of exercise on the pattern of muscle myostatin (MSTN) protein expression in two important metabolic disorders, i.e., obesity and diabetes mellitus. MSTN, is a negative regulator of skeletal muscle mass. We evaluated the effect of exercise on MSTN protein expression in diabetes mellitus and high fat diet-induced obesity. MSTN protein expression in gastrocnemius muscle was analyzed by Western Blot. P sedentary or exercised obese animals. Diabetes reduced gastrocnemius muscle weight in sedentary animals. However, gastrocnemius muscle weight increased in diabetic exercised animals. Both the precursor and processed forms of muscle MSTN protein were significantly higher in sedentary diabetic rats than in control rats. The precursor form was significantly lower in diabetic exercised animals than in diabetic sedentary animals. However, the processed form did not change. These results demonstrate that exercise can modulate the muscle expression of MSTN protein in diabetic rats and suggest that MSTN may be involved in energy homeostasis.
TRAF6 promotes myogenic differentiation via the TAK1/p38 mitogen-activated protein kinase and Akt pathways.

Directory of Open Access Journals (Sweden)

Fang Xiao

Full Text Available p38 mitogen-activated protein kinase (MAPK is an essential kinase involved in myogenic differentiation. Although many substrates of p38 MAPK have been identified, little is known about its upstream activators during myogenic differentiation. TRAF6 is known to function in cytokine signaling during inflammatory responses. However, not much is known about its role in myogenic differentiation and muscle regeneration. We showed here that TRAF6 and its intrinsic ubiquitin E3 ligase activity are required for myogenic differentiation. In mouse myoblasts, knockdown of TRAF6 compromised the p38 MAPK and Akt pathways, while deliberate activation of either pathway rescued the differentiation defect caused by TRAF6 knockdown. TAK1 acted as a key signal transducer downstream of TRAF6 in myogenic differentiation. In vivo, knockdown of TRAF6 in mouse muscles compromised the injury-induced muscle regeneration without impairing macrophage infiltration and myoblast proliferation. Collectively, we demonstrated that TRAF6 promotes myogenic differentiation and muscle regeneration via the TAK1/p38 MAPK and Akt pathways.
Exercise induced asthma and endogenous opioids.

Science.gov (United States)

Gaillard, R C; Bachman, M; Rochat, T; Egger, D; de Haller, R; Junod, A F

1986-01-01

Concentrations of endogenous opioid peptides in the plasma are increased during exercise and these substances have been implicated in the pathogenesis of asthma induced by chloropropramide and alcohol in diabetic patients. This work was undertaken to determine whether exercise induced asthma might be mediated by endogenous opioids. Plasma beta endorphin, met-enkephalin, and adrenocorticotrophic hormone (ACTH) concentrations were measured in five asthmatic patients and five normal volunteers breathing cold air during exercise. In four of the patients the effect of an infusion of naloxone on FEV1 was also measured during exercise induced asthma. Exercise produced acute bronchoconstriction in all asthmatics, characterised by a fall in FEV1; whereas no change occurred in normal subjects. There was no difference in plasma met-enkephalin, beta endorphin, and ACTH concentration between the two groups. Infusion of naloxone neither prevented nor worsened exercise induced asthma. These data suggest that endogenous opioids probably do not play a part in the development of exercise induced asthma. PMID:2944240
Efficient and reproducible myogenic differentiation from human iPS cells: prospects for modeling Miyoshi Myopathy in vitro.

Directory of Open Access Journals (Sweden)

Akihito Tanaka

Full Text Available The establishment of human induced pluripotent stem cells (hiPSCs has enabled the production of in vitro, patient-specific cell models of human disease. In vitro recreation of disease pathology from patient-derived hiPSCs depends on efficient differentiation protocols producing relevant adult cell types. However, myogenic differentiation of hiPSCs has faced obstacles, namely, low efficiency and/or poor reproducibility. Here, we report the rapid, efficient, and reproducible differentiation of hiPSCs into mature myocytes. We demonstrated that inducible expression of myogenic differentiation1 (MYOD1 in immature hiPSCs for at least 5 days drives cells along the myogenic lineage, with efficiencies reaching 70-90%. Myogenic differentiation driven by MYOD1 occurred even in immature, almost completely undifferentiated hiPSCs, without mesodermal transition. Myocytes induced in this manner reach maturity within 2 weeks of differentiation as assessed by marker gene expression and functional properties, including in vitro and in vivo cell fusion and twitching in response to electrical stimulation. Miyoshi Myopathy (MM is a congenital distal myopathy caused by defective muscle membrane repair due to mutations in DYSFERLIN. Using our induced differentiation technique, we successfully recreated the pathological condition of MM in vitro, demonstrating defective membrane repair in hiPSC-derived myotubes from an MM patient and phenotypic rescue by expression of full-length DYSFERLIN (DYSF. These findings not only facilitate the pathological investigation of MM, but could potentially be applied in modeling of other human muscular diseases by using patient-derived hiPSCs.
Efficient and Reproducible Myogenic Differentiation from Human iPS Cells: Prospects for Modeling Miyoshi Myopathy In Vitro

Science.gov (United States)

Tanaka, Akihito; Woltjen, Knut; Miyake, Katsuya; Hotta, Akitsu; Ikeya, Makoto; Yamamoto, Takuya; Nishino, Tokiko; Shoji, Emi; Sehara-Fujisawa, Atsuko; Manabe, Yasuko; Fujii, Nobuharu; Hanaoka, Kazunori; Era, Takumi; Yamashita, Satoshi; Isobe, Ken-ichi; Kimura, En; Sakurai, Hidetoshi

2013-01-01

The establishment of human induced pluripotent stem cells (hiPSCs) has enabled the production of in vitro, patient-specific cell models of human disease. In vitro recreation of disease pathology from patient-derived hiPSCs depends on efficient differentiation protocols producing relevant adult cell types. However, myogenic differentiation of hiPSCs has faced obstacles, namely, low efficiency and/or poor reproducibility. Here, we report the rapid, efficient, and reproducible differentiation of hiPSCs into mature myocytes. We demonstrated that inducible expression of myogenic differentiation1 (MYOD1) in immature hiPSCs for at least 5 days drives cells along the myogenic lineage, with efficiencies reaching 70–90%. Myogenic differentiation driven by MYOD1 occurred even in immature, almost completely undifferentiated hiPSCs, without mesodermal transition. Myocytes induced in this manner reach maturity within 2 weeks of differentiation as assessed by marker gene expression and functional properties, including in vitro and in vivo cell fusion and twitching in response to electrical stimulation. Miyoshi Myopathy (MM) is a congenital distal myopathy caused by defective muscle membrane repair due to mutations in DYSFERLIN. Using our induced differentiation technique, we successfully recreated the pathological condition of MM in vitro, demonstrating defective membrane repair in hiPSC-derived myotubes from an MM patient and phenotypic rescue by expression of full-length DYSFERLIN (DYSF). These findings not only facilitate the pathological investigation of MM, but could potentially be applied in modeling of other human muscular diseases by using patient-derived hiPSCs. PMID:23626698
Pharmacological targeting of HSP90 with 17-AAG induces apoptosis of myogenic cells through activation of the intrinsic pathway.

Science.gov (United States)

Wagatsuma, Akira; Takayama, Yuzo; Hoshino, Takayuki; Shiozuka, Masataka; Yamada, Shigeru; Matsuda, Ryoichi; Mabuchi, Kunihiko

2017-12-16

We have shown that pharmacological inhibition of HSP90 ATPase activity induces apoptosis of myoblasts during their differentiation. However, the signaling pathways remain not fully characterized. We report that pharmacological targeting of HSP90 with 17-AAG activates the intrinsic pathway including caspase-dependent and caspase-independent pathways. 17-AAG induces the typical apoptotic phenotypes including PARP cleavage, chromatin condensation, and nuclear fragmentation with mitochondrial release of cytochrome c, Smac/DIABLO, procaspase-9 processing, and caspase-3 activation. AIF and EndoG redistribute from the mitochondria into the cytosol and are partially translocated to the nucleus in 17-AAG-treated cells. These results suggest that caspase-dependent and caspase-independent pathways should be considered in apoptosis of myogenic cells induced by inhibition of HSP90 ATPase activity.
Histone deacetylase inhibitor trichostatin A enhances myogenesis by coordinating muscle regulatory factors and myogenic repressors

International Nuclear Information System (INIS)

Hagiwara, Hiroki; Saito, Fumiaki; Masaki, Toshihiro; Ikeda, Miki; Nakamura-Ohkuma, Ayami; Shimizu, Teruo; Matsumura, Kiichiro

2011-01-01

Highlights: ► We investigated the effect of TSA, one of most potent HDACIs, on myogenesis using the C2C12 skeletal muscle cell line. ► TSA enhances the expression of myosin heavy chain without affecting DAPC expression. ► TSA enhances the expression of the early MRFs, Myf5 and MEF2, and suppresses the late MRF, myogenin, after 24 h treatment. ► TSA enhances the expression of the myogenic repressors, Ids, which inhibit myogenic differentiation. ► TSA promotes myogenesis by coordinating the expression of MRFs and myogenic repressors. -- Abstract: Histone deacetylase inhibitors (HDACIs) are known to promote skeletal muscle formation. However, their mechanisms that include effects on the expression of major muscle components such as the dystrophin-associated proteins complex (DAPC) or myogenic regulatory factors (MRFs) remain unknown. In this study, we investigated the effects of HDACIs on skeletal muscle formation using the C2C12 cell culture system. C2C12 myoblasts were exposed to trichostatin A (TSA), one of the most potent HDACIs, and differentiation was subsequently induced. We found that TSA enhances the expression of myosin heavy chain without affecting DAPC expression. In addition, TSA increases the expression of the early MRFs, Myf5 and MEF2, whereas it suppresses the expression of the late MRF, myogenin. Interestingly, TSA also enhances the expression of Id1, Id2, and Id3 (Ids). Ids are myogenic repressors that inhibit myogenic differentiation. These findings suggest that TSA promotes gene expression in proliferation and suppresses it in the differentiation stage of muscle formation. Taken together, our data demonstrate that TSA enhances myogenesis by coordinating the expression of MRFs and myogenic repressors.
Trauma-induced systemic inflammatory response versus exercise-induced immunomodulatory effects.

Science.gov (United States)

Fehrenbach, Elvira; Schneider, Marion E

2006-01-01

Accidental trauma and heavy endurance exercise, both induce a kind of systemic inflammatory response, also called systemic inflammatory response syndrome (SIRS). Exercise-related SIRS is conditioned by hyperthermia and concomitant heat shock responses, whereas trauma-induced SIRS manifests concomitantly with tissue necrosis and immune activation, secondarily followed by fever. Inflammatory cytokines are common denominators in both trauma and exercise, although there are marked quantitative differences. Different anti-inflammatory cytokines may be involved in the control of inflammation in trauma- and exercise-induced stress. Exercise leads to a balanced equilibrium between inflammatory and anti-inflammatory responses. Intermittent states of rest, as well as anti-oxidant capacity, are lacking or minor in trauma but are high in exercising individuals. Regular training may enhance immune competence, whereas trauma-induced SIRS often paves the way for infectious complications, such as sepsis.
Localized cyclic AMP-dependent protein kinase activity is required for myogenic cell fusion

International Nuclear Information System (INIS)

Mukai, Atsushi; Hashimoto, Naohiro

2008-01-01

Multinucleated myotubes are formed by fusion of mononucleated myogenic progenitor cells (myoblasts) during terminal skeletal muscle differentiation. In addition, myoblasts fuse with myotubes, but terminally differentiated myotubes have not been shown to fuse with each other. We show here that an adenylate cyclase activator, forskolin, and other reagents that elevate intracellular cyclic AMP (cAMP) levels induced cell fusion between small bipolar myotubes in vitro. Then an extra-large myotube, designated a 'myosheet,' was produced by both primary and established mouse myogenic cells. Myotube-to-myotube fusion always occurred between the leading edge of lamellipodia at the polar end of one myotube and the lateral plasma membrane of the other. Forskolin enhanced the formation of lamellipodia where cAMP-dependent protein kinase (PKA) was accumulated. Blocking enzymatic activity or anchoring of PKA suppressed forskolin-enhanced lamellipodium formation and prevented fusion of multinucleated myotubes. Localized PKA activity was also required for fusion of mononucleated myoblasts. The present results suggest that localized PKA plays a pivotal role in the early steps of myogenic cell fusion, such as cell-to-cell contact/recognition through lamellipodium formation. Furthermore, the localized cAMP-PKA pathway might be involved in the specification of the fusion-competent areas of the plasma membrane in lamellipodia of myogenic cells
Test-retest reliabilty of exercise-induced hypoalgesia after aerobic exercise

DEFF Research Database (Denmark)

Vaegter, Henrik Bjarke; Dørge, Daniel Bandholtz; Schmidt, Kristian Sonne

2018-01-01

Objective: Exercise increases pressure pain thresholds (PPTs) in exercising and nonexercising muscles, known as exercise-induced hypoalgesia (EIH). No studies have investigated the test-retest reliability of change in PPTs after aerobic exercise. Primary objectives were to compare the effect...
Nociception contributes to the formation of myogenic contracture in the early phase of adjuvant-induced arthritis in a rat knee.

Science.gov (United States)

Kaneguchi, Akinori; Ozawa, Junya; Moriyama, Hideki; Yamaoka, Kaoru

2017-07-01

It is unknown how joint contracture is generated in inflamed joints. This study aimed to clarify the role of nociception on the formation of joint contracture secondary to arthritis. Monoarthritis was induced by intra-articular injections of complete Freund's adjuvant (CFA) into rat knees. On day 5 after CFA injection, the passive extension range of motion (ROM) of knee joints were measured, both before and after myotomy of knee flexors, to evaluate the extent of muscular contribution to CFA-induced joint contracture. The steroidal anti-inflammatory drug dexamethasone could prevent ROM restrictions completely, both before and after myotomy. On the other hand, the opioid analgesic drug morphine did not prevent the development of restricted ROM observed after myotomy, while it did before myotomy. This indicates that nociception contributes to joint contracture through alterations in muscular structure (myogenic factors). Next, we tested the hypothesis that nociception-induced reflexive flexor muscle contractions cause myogenic contracture in arthritic joints. To do this, chemical denervation was performed by Botulinum toxin type A (BTX-A) injections into knee flexor muscles, simultaneously with CFA injections into the knee. As expected, BTX-A could alleviate ROM restrictions observed before myotomy. These findings suggest that nociceptive-related muscle contractions play an essential role in the formation of joint contracture. Thus, our study indicates that analgesic management during an early stage of joint arthritis is an essential mean to prevent the formation of joint contracture. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1404-1413, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
PERSONALITY DOES NOT INFLUENCE EXERCISE-INDUCED MOOD ENHANCEMENT AMONG FEMALE EXERCISERS

Directory of Open Access Journals (Sweden)

Andrew M. Lane

2005-09-01

Full Text Available The present study investigated the influence of personality on exercise-induced mood changes. It was hypothesised that (a exercise would be associated with significant mood enhancement across all personality types, (b extroversion would be associated with positive mood and neuroticism with negative mood both pre- and post-exercise, and (c personality measures would interact with exercise-induced mood changes. Participants were 90 female exercisers (M = 25.8 yr, SD = 9.0 yr who completed the Eysenck Personality Inventory (EPI once and the Brunel Mood Scale (BRUMS before and after a 60-minute exercise session. Median splits were used to group participants into four personality types: stable introverts (n = 25, stable extroverts (n = 20, neurotic introverts (n = 26, and neurotic extroverts (n = 19. Repeated measures MANOVA showed significant mood enhancement following exercise across all personality types. Neuroticism was associated with negative mood scores pre- and post-exercise but the effect of extroversion on reported mood was relatively weak. There was no significant interaction effect between exercise-induced mood enhancement and personality. In conclusion, findings lend support to the notion that exercise is associated with improved mood. However, findings show that personality did not influence this effect, although neuroticism was associated with negative mood
Bronchial or Laryngeal Obstruction Induced by Exercise?

Directory of Open Access Journals (Sweden)

Ayoub Bey

2017-06-01

Full Text Available A child suspected of exercise-induced laryngeal obstruction and asthma is examined by laryngoscopy and respiratory resistance (Rrs after exercise challenge. Immediately at exercise cessation, the visualized adduction of the larynx in inspiration is reflected in a paroxystic increase in Rrs. While normal breathing has apparently resumed later on during recovery from exercise, the pattern of Rrs in inspiration is observed to reoccur following a deep breath or swallowing. The procedure may thus help diagnosing the site of exercise-induced obstruction when laryngoscopy is not available and identify re-inducers of laryngeal dysfunction.
Skeletal myogenic differentiation of human urine-derived cells as a potential source for skeletal muscle regeneration.

Science.gov (United States)

Chen, Wei; Xie, Minkai; Yang, Bin; Bharadwaj, Shantaram; Song, Lujie; Liu, Guihua; Yi, Shanhong; Ye, Gang; Atala, Anthony; Zhang, Yuanyuan

2017-02-01

Stem cells are regarded as possible cell therapy candidates for skeletal muscle regeneration. However, invasive harvesting of those cells can cause potential harvest-site morbidity. The goal of this study was to assess whether human urine-derived stem cells (USCs), obtained through non-invasive procedures, can differentiate into skeletal muscle linage cells (Sk-MCs) and potentially be used for skeletal muscle regeneration. In this study, USCs were harvested from six healthy individuals aged 25-55. Expression profiles of cell-surface markers were assessed by flow cytometry. To optimize the myogenic differentiation medium, we selected two from four different types of myogenic differentiation media to induce the USCs. Differentiated USCs were identified with myogenic markers by gene and protein expression. USCs were implanted into the tibialis anterior muscles of nude mice for 1 month. The results showed that USCs displayed surface markers with positive staining for CD24, CD29, CD44, CD73, CD90, CD105, CD117, CD133, CD146, SSEA-4 and STRO-1, and negative staining for CD14, CD31, CD34 and CD45. After myogenic differentiation, a change in morphology was observed from 'rice-grain'-like cells to spindle-shaped cells. The USCs expressed specific Sk-MC transcripts and protein markers (myf5, myoD, myosin, and desmin) after being induced with different myogenic culture media. Implanted cells expressed Sk-MC markers stably in vivo. Our findings suggest that USCs are able to differentiate into the Sk-MC lineage in vitro and after being implanted in vivo. Thus, they might be a potential source for cell injection therapy in the use of skeletal muscle regeneration. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.
[Exercise-induced inspiratory stridor. An important differential diagnosis of exercise-induced asthma].

Science.gov (United States)

Christensen, Pernille; Thomsen, Simon Francis; Rasmussen, Niels; Backer, Vibeke

2007-11-19

Recent studies suggest that exercise-induced inspiratory stridor (EIIS) is an important and often overlooked differential diagnosis of exercise-induced asthma. EIIS is characterised by astma-like symptoms, but differs by inspiratory limitation, fast recovery, and a lack of effect of inhaled bronchodilators. The prevalence of EIIS is reported to be 5-27%, and affects both children and adults. The pathophysiology, the pathogenesis, and the treatment of the condition are not yet clarified. At present, a population-based study is being conducted in order to address these points.
The influence of anti-inflammatory medication on exercise-induced myogenic precursor cell responses in humans

DEFF Research Database (Denmark)

Mackey, Abigail L; Kjaer, Michael; Dandanell, Sune

2007-01-01

The consumption of nonsteroidal anti-inflammatory drugs (NSAIDs) is widespread among athletes when faced with muscle soreness or injury, but the effects of NSAIDs on satellite cell activity in humans are unknown. To investigate this, 14 healthy male endurance athletes (mean peak oxygen consumption...... 62 ml x kg(-1) x min(-1)) volunteered for the study, which involved running 36 km. They were divided into two groups and received either 100 mg indomethacin per day or placebo. Muscle biopsies collected before the run and on days 1, 3, and 8 afterward were analyzed for satellite cells...
Aberrant Splicing Induced by Dysregulated Rbfox2 Produces Enhanced Function of CaV1.2 Calcium Channel and Vascular Myogenic Tone in Hypertension.

Science.gov (United States)

Zhou, Yingying; Fan, Jia; Zhu, Huayuan; Ji, Li; Fan, Wenyong; Kapoor, Isha; Wang, Yue; Wang, Yuan; Zhu, Guoqing; Wang, Juejin

2017-12-01

Calcium influx from activated voltage-gated calcium channel Ca V 1.2 in vascular smooth muscle cells is indispensable for maintaining myogenic tone and blood pressure. The function of Ca V 1.2 channel can be optimized by alternative splicing, one of post-transcriptional modification mechanisms. The splicing factor Rbfox2 is known to regulate the Ca V 1.2 pre-mRNA alternative splicing events during neuronal development. However, Rbfox2's roles in modulating the key function of vascular Ca V 1.2 channel and in the pathogenesis of hypertension remain elusive. Here, we report that the proportion of Ca V 1.2 channels with alternative exon 9* is increased by 10.3%, whereas that with alternative exon 33 is decreased by 10.5% in hypertensive arteries. Surprisingly, the expression level of Rbfox2 is increased ≈3-folds, presumably because of the upregulation of a dominant-negative isoform of Rbfox2. In vascular smooth muscle cells, we find that knockdown of Rbfox2 dynamically increases alternative exon 9*, whereas decreases exon 33 inclusion of Ca V 1.2 channels. By patch-clamp studies, we show that diminished Rbfox2-induced alternative splicing shifts the steady-state activation and inactivation curves of vascular Ca V 1.2 calcium channel to hyperpolarization, which makes the window current potential to more negative. Moreover, siRNA-mediated knockdown of Rbfox2 increases the pressure-induced vascular myogenic tone of rat mesenteric artery. Taken together, our data indicate that Rbfox2 modulates the functions of vascular Ca V 1.2 calcium channel by dynamically regulating the expressions of alternative exons 9* and 33, which in turn affects the vascular myogenic tone. Therefore, our work suggests a key role for Rbfox2 in hypertension, which provides a rational basis for designing antihypertensive therapies. © 2017 American Heart Association, Inc.
Effect of Losartan on the Acute Response of Human Elderly Skeletal Muscle to Exercise

DEFF Research Database (Denmark)

Heisterberg, Mette Flindt; Andersen, Jesper L; Schjerling, Peter

2018-01-01

targets, with no specific effect of losartan on these. However, when compared with placebo, Losartan intake resulted in a greater suppression of myostatin mRNA. CONCLUSION: In general, there does not appear to be any effect of AT1R blocking upon satellite cell number or myogenic pathways in elderly men...... in the days after one bout of heavy resistance exercise. However, the greater suppression of myostatin may prove to be beneficial over a long term intervention designed to induce hypertrophy....
[Exercise-induced rhabdomyolysis - a new trend?

Science.gov (United States)

Fardal, Hilde; Gøransson, Lasse G

2016-10-01

The purpose of this study was to investigate whether or not there has been an increase in the number of admissions for exercise-induced rhabdomyolysis at Stavanger University Hospital (SUS) in recent years. The study is a retrospective review of patients discharged over the period January 2010 to March 2015 with a diagnosis of exercise-induced rhabdomyolysis and with maximum creatine kinase (CK) levels more than ten times the upper reference limit. A total of 33 patients, 21 women and 12 men, with a median age of 28 years (18 - 68), were included in the study. Of the 33 patients, three quarters (25) were admitted in 2014 - 15, compared with eight over the period 2010 - 13. One patient developed kidney failure that required dialysis. The treatment depended more on the attending physician and department than on the patient's clinical condition and CK-level, but this did not seem to affect the rate of complications. The incidence of exercise-induced rhabdomyolysis at SUS increased from autumn 2014, and this coincided with increased media attention and a new exercise trend. We recommend standardising the treatment of exercise-induced rhabdomyolysis, as current treatment recommendations are based on rhabdomyolysis triggered by causes other than exercise.
Small activating RNA induces myogenic differentiation of rat adipose-derived stem cells by upregulating MyoD

Directory of Open Access Journals (Sweden)

Chenghe Wang

2015-08-01

Full Text Available ABSTRACTPurpose:RNA activation (RNAa is a mechanism of gene activation triggered by promoter-targeted small double stranded RNAs (dsRNAs, also known as small activating RNAs (saRNAs. Myogenic regulatory factor MyoD is regarded as the master activator of myogenic differentiation cascade by binding to enhancer of muscle specific genes. Stress urinary incontinence (SUI is a condition primarily resulted from urethral sphincter deficiency. It is thus expected that by promoting differentiation of adipose-derived stem cells (ADSCs into myoblasts by activating MyoD gene through RNAa may offer benefits to SUI.Materials and Methods:Rats ADSCs were isolated, proliferated in vitro, and identified by flow cytometry. Purified ADSCs were then transfected with a MyoD saRNA or control transfected. Real-time polymerase chain reaction (RT-PCR and western blotting were used to detect MyoD mRNA and protein expression, respectively. Immunocytochemical staining was applied to determine the expression of desmin protein in transfected cells. Cell viability was measured by using CellTiter 96® AQueous One Solution Cell Proliferation Assay kit.Results:Transfection of a MyoD saRNA (dsMyoD into ADSCs significantly induced the expression of MyoD at both the mRNA and protein levels, and inhibited cell proliferation. Desmin protein expression was detected in dsMyoD treated ADSCs 2 weeks later.Conclusion:Our findings show that RNAa mediated overexpression of MyoD can promote transdifferentiation of ADSCs into myoblasts and may help treat stress urinary incontinence (SUI–a condition primarily resulted from urethral sphincter deficiency.

βENaC acts as a mechanosensor in renal vascular smooth muscle cells that contributes to renal myogenic blood flow regulation, protection from renal injury and hypertension.

Science.gov (United States)

Drummond, Heather A; Stec, David E

2015-06-01

Pressure-induced constriction (also known as the "myogenic response") is an important mechanodependent response in small renal arteries and arterioles. The response is initiated by vascular smooth muscle cell (VSMC) stretch due to an increase in intraluminal pressure and leads to vasoconstriction. The myogenic response has two important roles as a mechanism of local blood flow autoregulation and protection against systemic blood pressure-induced microvascular damage. However, the molecular mechanisms underlying initiation of myogenic response are unresolved. Although several molecules have been considered initiators of the response, our laboratory has focused on the role of degenerin proteins because of their strong evolutionary link to mechanosensing in the nematode. Our laboratory has addressed the hypothesis that certain degenerin proteins act as mechanosensors in VSMCs. This article discusses the importance of a specific degenerin protein, β Epithelial Na + Channel (βENaC), in pressure-induced vasoconstriction, renal blood flow and susceptibility to renal injury. We propose that loss of the renal myogenic constrictor response delays the correction of renal blood flow that occurs with fluctuations in systemic pressure, which allows pressure swings to be transmitted to the microvasculature, thus increasing the susceptibility to renal injury and hypertension. The role of βENaC in myogenic regulation is independent of tubular βENaC and thus represents a non-tubular role for βENaC in renal-cardiovascular homeostasis.
miR-206 represses hypertrophy of myogenic cells but not muscle fibers via inhibition of HDAC4.

Science.gov (United States)

Winbanks, Catherine E; Beyer, Claudia; Hagg, Adam; Qian, Hongwei; Sepulveda, Patricio V; Gregorevic, Paul

2013-01-01

microRNAs regulate the development of myogenic progenitors, and the formation of skeletal muscle fibers. However, the role miRNAs play in controlling the growth and adaptation of post-mitotic musculature is less clear. Here, we show that inhibition of the established pro-myogenic regulator miR-206 can promote hypertrophy and increased protein synthesis in post-mitotic cells of the myogenic lineage. We have previously demonstrated that histone deacetylase 4 (HDAC4) is a target of miR-206 in the regulation of myogenic differentiation. We confirmed that inhibition of miR-206 de-repressed HDAC4 accumulation in cultured myotubes. Importantly, inhibition of HDAC4 activity by valproic acid or sodium butyrate prevented hypertrophy of myogenic cells otherwise induced by inhibition of miR-206. To test the significance of miRNA-206 as a regulator of skeletal muscle mass in vivo, we designed recombinant adeno-associated viral vectors (rAAV6 vectors) expressing miR-206, or a miR-206 "sponge," featuring repeats of a validated miR-206 target sequence. We observed that over-expression or inhibition of miR-206 in the muscles of mice decreased or increased endogenous HDAC4 levels respectively, but did not alter muscle mass or myofiber size. We subsequently manipulated miR-206 levels in muscles undergoing follistatin-induced hypertrophy or denervation-induced atrophy (models of muscle adaptation where endogenous miR-206 expression is altered). Vector-mediated manipulation of miR-206 activity in these models of cell growth and wasting did not alter gain or loss of muscle mass respectively. Our data demonstrate that although the miR-206/HDAC4 axis operates in skeletal muscle, the post-natal expression of miR-206 is not a key regulator of basal skeletal muscle mass or specific modes of muscle growth and wasting. These studies support a context-dependent role of miR-206 in regulating hypertrophy that may be dispensable for maintaining or modifying the adult skeletal muscle phenotype
The NAD(+) precursor nicotinamide riboside decreases exercise performance in rats.

Science.gov (United States)

Kourtzidis, Ioannis A; Stoupas, Andreas T; Gioris, Ioannis S; Veskoukis, Aristidis S; Margaritelis, Nikos V; Tsantarliotou, Maria; Taitzoglou, Ioannis; Vrabas, Ioannis S; Paschalis, Vassilis; Kyparos, Antonios; Nikolaidis, Michalis G

2016-01-01

Nicotinamide adenine dinucleotide (NAD(+)) and its phosphorylated form (NADP(+)) are key molecules in ubiquitous bioenergetic and cellular signaling pathways, regulating cellular metabolism and homeostasis. Thus, supplementation with NAD(+) and NADP(+) precursors emerged as a promising strategy to gain many and multifaceted health benefits. In this proof-of-concept study, we sought to investigate whether chronic nicotinamide riboside administration (an NAD(+) precursor) affects exercise performance. Eighteen Wistar rats were equally divided in two groups that received either saline vehicle or nicotinamide riboside at a dose of 300 mg/kg body weight/day for 21 days via gavage. At the end of the 21-day administration protocol, both groups performed an incremental swimming performance test. The nicotinamide riboside group showed a tendency towards worse physical performance by 35 % compared to the control group at the final 10 % load (94 ± 53 s for the nicotinamide riboside group and 145 ± 59 s for the control group; P = 0.071). Our results do not confirm the previously reported ergogenic effect of nicotinamide riboside. The potentially negative effect of nicotinamide riboside administration on physical performance may be attributed to the pleiotropic metabolic and redox properties of NAD(+) and NADP(+).
PREFERRED MODALITY INFLUENCES ON EXERCISE-INDUCED MOOD CHANGES

Directory of Open Access Journals (Sweden)

Andrew M. Lane

2005-06-01

Full Text Available The present study tested, both retrospectively and prospectively, exercise-induced mood changes among regular exercisers. Specifically, it examined the extent to which preferred exercise modality promoted greater mood benefits. A group of 25 exercise participants (M = 35.5 yr., SD = 10.5 yr. took part in the study. All participants had exercised at least three times a week (M = 3.5, SD = 2.3 during the previous year. Participants completed a 14-item Exercise Preference Questionnaire to provide retrospective evaluations of their most- and least-preferred type of exercise. For the prospective investigation, participants completed the Brunel Mood Scale (BRUMS 15 minutes before and immediately after their most- and least-preferred exercise sessions. One week separated completion of each exercise session. Retrospective assessment of exercise-induced mood changes showed strong support for enhanced mood following the preferred mode of exercise. Also, as hypothesized, prospective results showed that mood enhancement was greater following the preferred exercise modality, but significant mood enhancement also occurred following the least-preferred modality among experienced exercisers. In conclusions, findings support the principle that exercise can provide psychological benefits to its participants, in the form of positive affective outcomes, something that appears to be enhanced by preferred exercise modality. Given the important public health implications of exercise adherence, future research should seek to further investigate the mechanisms of exercise-induced mood enhancement
AMPKα in Exercise-Induced Substrate Metabolism and Exercise Training-Induced Metabolic and Mitochondrial Adaptations

DEFF Research Database (Denmark)

Fentz, Joachim

in response to 4 weeks of voluntary running wheel exercise training. However, the acute exercise-induced increase in mRNA expression of several metabolic and mitochondrial marker genes is impaired in the mice lacking AMPKα1 and α2. In addition to the two studies and some currently unpublished data this thesis...
Food-dependent exercise-induced anaphylaxis to flaxseed

Directory of Open Access Journals (Sweden)

Helmut Gall

2000-01-01

Full Text Available The present paper reports on a 26-year-old atopic patient suffering from seasonal rhinoconjunctivitis and flexural eczemas. On two occasions, he experienced nausea, generalized urticaria and dyspnea within 2 h after consumption of a wholemeal roll and subsequent exercise (football training or walking. In each case, the episode necessitated intravenous emergency therapy with an antihistamine and a corticosteroid. In order to elucidate the two exercise-induced anaphylactic events we performed prick tests and the radioallergosorbent test (RAST with the ingredients of the wholemeal roll. Only flaxseed gave positive results. In addition, we performed an exercise test on a bicycle ergometer (15 min at 150 W and an oral challenge test with foods, using a double-blind and placebo-controlled study. Only oral challenge with a teaspoon of flaxseed with additional exercise on the bicycle ergometer elicited itching, urticaria, nausea, coughing and dyspnea. The oral challenge with flaxseed followed by exercise induced immediate-type reactions and, thus, led to the diagnosis of food-dependent exercise- induced anaphylaxis to flaxseed.
Exercise-induced inspiratory symptoms in school children

DEFF Research Database (Denmark)

Buchvald, Frederik; Phillipsen, Lue Drasbaek; Hjuler, Thomas

2016-01-01

BACKGROUND AND AIMS: Exercise-induced inspiratory symptoms (EIIS) have multiple causes, one of which is exercise-induced laryngeal obstruction (EILO). There is limited knowledge regarding EIIS in children, both in primary care practices and in pediatric asthma clinics. The aim of this study was t...
Exercise excess pressure and exercise-induced albuminuria in patients with type 2 diabetes mellitus.

Science.gov (United States)

Climie, Rachel E D; Srikanth, Velandai; Keith, Laura J; Davies, Justin E; Sharman, James E

2015-05-01

Exercise-induced albuminuria is common in patients with type 2 diabetes mellitus (T2DM) in response to maximal exercise, but the response to light-moderate exercise is unclear. Patients with T2DM have abnormal central hemodynamics and greater propensity for exercise hypertension. This study sought to determine the relationship between light-moderate exercise central hemodynamics (including aortic reservoir and excess pressure) and exercise-induced albuminuria. Thirty-nine T2DM (62 ± 9 yr; 49% male) and 39 nondiabetic controls (53 ± 9 yr; 51% male) were examined at rest and during 20 min of light-moderate cycle exercise (30 W; 50 revolutions/min). Albuminuria was assessed by the albumin-creatinine ratio (ACR) at rest and 30 min postexercise. Hemodynamics recorded included brachial and central blood pressure (BP), aortic stiffness, augmented pressure (AP), aortic reservoir pressure, and excess pressure integral (Pexcess). There was no difference in ACR between groups before exercise (P > 0.05). Exercise induced a significant rise in ACR in T2DM but not controls (1.73 ± 1.43 vs. 0.53 ± 1.0 mg/mol, P = 0.002). All central hemodynamic variables were significantly higher during exercise in T2DM (i.e., Pexcess, systolic BP and AP; P exercise Pexcess was associated with postexercise ACR (r = 0.51, P = 0.002), and this relationship was independent of age, sex, body mass index, heart rate, aortic stiffness, antihypertensive medication, and ambulatory daytime systolic BP (β = 0.003, P = 0.003). Light-moderate exercise induced a significant rise in ACR in T2DM, and this was independently associated with Pexcess, a potential marker of vascular dysfunction. These novel findings suggest that Pexcess could be important for appropriate renal function in T2DM. Copyright © 2015 the American Physiological Society.
Nox4 Is Dispensable for Exercise Induced Muscle Fibre Switch.

Directory of Open Access Journals (Sweden)

Juri Vogel

Full Text Available By producing H2O2, the NADPH oxidase Nox4 is involved in differentiation of mesenchymal cells. Exercise alters the composition of slow and fast twitch fibres in skeletal. Here we hypothesized that Nox4 contributes to exercise-induced adaptation such as changes in muscle metabolism or muscle fibre specification and studied this in wildtype and Nox4-/- mice.Exercise, as induced by voluntary running in a running wheel or forced running on a treadmill induced a switch from fast twitch to intermediate fibres. However the induced muscle fibre switch was similar between Nox4-/- and wildtype mice. The same held true for exercise-induced expression of PGC1α or AMPK activation. Both are increased in response to exercise, but with no difference was observed between wildtype and Nox4-/- mice.Thus, exercise-induced muscle fibre switch is Nox4-independent.
PGC-1alpha in exercise- and exercise training-induced metabolic adaptations

DEFF Research Database (Denmark)

Jørgensen, Stine Ringholm

and interferes with the exercise-induced adaptive response in human skeletal muscle. Study II demonstrates that mouse liver glucose-6-phosphatase (G6Pase) mRNA content increased in recovery from acute exercise in both wildtype (WT) and PGC-1α knockout (KO) mice, while phosphoenolpyruvate carboxykinase (PEPCK......) and pyruvate carboxylase mRNA content did not change in either genotype. Exercise training increased PEPCK protein content in both WT and PGC-1α KO mice. In addition, the mRNA and protein content of cytochrome (Cyt) c and cytochrome c oxidase (COX) subunit I increased in response to acute exercise and exercise...
The Effects of Acute Dopamine Precursor Depletion on the Reinforcing Value of Exercise in Anorexia Nervosa.

Directory of Open Access Journals (Sweden)

Caitlin B O'Hara

Full Text Available This study investigated whether dopaminergic systems are involved in the motivation to engage in behaviours associated with anorexia nervosa (AN, specifically, the drive to exercise. Women recovered from AN (AN REC, n = 17 and healthy controls (HC, n = 15 were recruited. The acute phenylalanine/tyrosine depletion (APTD method was used to transiently decrease dopamine synthesis and transmission. The effect of dopamine precursor depletion on drive to exercise was measured using a progressive ratio (PR exercise breakpoint task. Both groups worked for the opportunity to exercise, and, at baseline, PR breakpoint scores were higher in AN REC than HC. Compared to values on the experimental control session, APTD did not decrease PR breakpoint scores in AN REC, but significantly decreased scores in HC. These data show that women recovered from AN are more motivated to exercise than HC, although in both groups, activity is more reinforcing than inactivity. Importantly, decreasing dopamine does not reduce the motivation to exercise in people recovered from AN, but in contrast, does so in HC. It is proposed that in AN, drive to exercise develops into a behaviour that is largely independent of dopamine mediated reward processes and becomes dependent on cortico-striatal neurocircuitry that regulates automated, habit- or compulsive-like behaviours. These data strengthen the case for the involvement of reward, learning, habit, and dopaminergic systems in the aetiology of AN.
Exercise-induced rhabdomyolysis - a patient series.

Science.gov (United States)

Tazmini, Kiarash; Schreiner, Christoffer; Bruserud, Sidsel; Raastad, Truls; Solberg, Erik Ekker

2017-11-14

No guidelines are available for the treatment and follow up of exercise-induced rhabdomyolysis. The purpose of this study was to describe the treatment, complications and follow-up of patients with exercise-induced rhabdomyolysis at Diakonhjemmet Hospital. A retrospective observational study from 2011 up to and including 2015 of patients with exercise-induced rhabdomyolysis ≥ 18 years and with creatine kinase > 5 000 IU/l. We registered a total of 42 patients and obtained informed consent from 31. Twenty were treated as inpatients with a median hospitalisation time of 2.5 (1–6) days. Median creatine kinase was 36 797 (17 172–53 548) IU/l upon admission and 16 051 (11 845–26 505) IU/l at discharge. Median intravenous fluid volume was 6 000 (1 000–27 700) ml. Eleven patients underwent urinary alkalinisation. None developed severe kidney injury or other serious complications such as electrolyte imbalance, compartment syndrome or disseminated intravascular coagulation, either during hospitalisation or in the course of the study period. Healthy persons with exercise-induced rhabdomyolysis have a very low risk of complications. Our patients are treated as outpatients or considered for discharge with creatine kinase < 40 000 IU/l measured at least three days after their workout, and if they have no risk factors or other complications.
Tumor necrosis factor-alpha inhibits differentiation of myogenic cells in human urethral rhabdosphincter.

Science.gov (United States)

Shinohara, Mayuka; Sumino, Yasuhiro; Sato, Fuminori; Kiyono, Tohru; Hashimoto, Naohiro; Mimata, Hiromitsu

2017-06-01

To examine the inhibitory effects of tumor necrosis factor-α on myogenic differentiation of human urethral rhabdosphincter cells. A rhabdosphincter sample was obtained from a patient who underwent total cystectomy. To expand the lifespan of the primary cultured cells, rhabdosphincter myogenic cells were immortalized with mutated cyclin-dependent kinase 4, cyclin D1 and telomerase. The differential potential of the cells was investigated. The transfected human rhabdosphincter cells were induced for myogenic differentiation with recombinant human tumor necrosis factor-α and/or the tumor necrosis factor-α antagonist etanercept at different concentrations, and activation of signaling pathways was monitored. Human rhabdosphincter cells were selectively cultured for at least 40 passages. Molecular analysis confirmed the expression of myosin heavy chain, which is a specific marker of differentiated muscle cells, significantly increased after differentiation induction. Although tumor necrosis factor-α treatment reduced the myosin heavy chain expression in a concentration-dependent manner, etanercept inhibited this suppression. Tumor necrosis factor-α suppressed phosphorylation of protein kinase B and p38, whereas etanercept pretreatment promoted phosphorylation and myosin heavy chain expression in a concentration-dependent manner. Tumor necrosis factor-α inhibits differentiation of urethral rhabdosphincter cells in part through the p38 mitogen-activated protein kinase and phosphoinositide 3-kinase pathways. Inhibition of tumor necrosis factor-α might be a useful strategy to treat stress urinary incontinence. © 2017 The Japanese Urological Association.
Efficient myogenic differentiation of human adipose-derived stem cells by the transduction of engineered MyoD protein

Energy Technology Data Exchange (ETDEWEB)

Sung, Min Sun [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Biosystems and Bioengineering Program, University of Science and Technology (UST), Daejeon 305-350 (Korea, Republic of); Mun, Ji-Young [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Kwon, Ohsuk [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Biosystems and Bioengineering Program, University of Science and Technology (UST), Daejeon 305-350 (Korea, Republic of); Kwon, Ki-Sun [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Oh, Doo-Byoung, E-mail: dboh@kribb.re.kr [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Biosystems and Bioengineering Program, University of Science and Technology (UST), Daejeon 305-350 (Korea, Republic of)

2013-07-19

Highlights: •MyoD was engineered to contain protein transduction domain and endosome-disruptive INF7 peptide. •The engineered MyoD-IT showed efficient nuclear targeting through an endosomal escape by INF7 peptide. •By applying MyoD-IT, human adipose-derived stem cells (hASCs) were differentiated into myogenic cells. •hASCs differentiated by applying MyoD-IT fused to myotubes through co-culturing with mouse myoblasts. •Myogenic differentiation using MyoD-IT is a safe method without the concern of altering the genome. -- Abstract: Human adipose-derived stem cells (hASCs) have great potential as cell sources for the treatment of muscle disorders. To provide a safe method for the myogenic differentiation of hASCs, we engineered the MyoD protein, a key transcription factor for myogenesis. The engineered MyoD (MyoD-IT) was designed to contain the TAT protein transduction domain for cell penetration and the membrane-disrupting INF7 peptide, which is an improved version of the HA2 peptide derived from influenza. MyoD-IT showed greatly improved nuclear targeting ability through an efficient endosomal escape induced by the pH-sensitive membrane disruption of the INF7 peptide. By applying MyoD-IT to a culture, hASCs were efficiently differentiated into long spindle-shaped myogenic cells expressing myosin heavy chains. Moreover, these cells differentiated by an application of MyoD-IT fused to myotubes with high efficiency through co-culturing with mouse C2C12 myoblasts. Because internalized proteins can be degraded in cells without altering the genome, the myogenic differentiation of hASCs using MyoD-IT would be a safe and clinically applicable method.
Efficient myogenic differentiation of human adipose-derived stem cells by the transduction of engineered MyoD protein

International Nuclear Information System (INIS)

Sung, Min Sun; Mun, Ji-Young; Kwon, Ohsuk; Kwon, Ki-Sun; Oh, Doo-Byoung

2013-01-01

Highlights: •MyoD was engineered to contain protein transduction domain and endosome-disruptive INF7 peptide. •The engineered MyoD-IT showed efficient nuclear targeting through an endosomal escape by INF7 peptide. •By applying MyoD-IT, human adipose-derived stem cells (hASCs) were differentiated into myogenic cells. •hASCs differentiated by applying MyoD-IT fused to myotubes through co-culturing with mouse myoblasts. •Myogenic differentiation using MyoD-IT is a safe method without the concern of altering the genome. -- Abstract: Human adipose-derived stem cells (hASCs) have great potential as cell sources for the treatment of muscle disorders. To provide a safe method for the myogenic differentiation of hASCs, we engineered the MyoD protein, a key transcription factor for myogenesis. The engineered MyoD (MyoD-IT) was designed to contain the TAT protein transduction domain for cell penetration and the membrane-disrupting INF7 peptide, which is an improved version of the HA2 peptide derived from influenza. MyoD-IT showed greatly improved nuclear targeting ability through an efficient endosomal escape induced by the pH-sensitive membrane disruption of the INF7 peptide. By applying MyoD-IT to a culture, hASCs were efficiently differentiated into long spindle-shaped myogenic cells expressing myosin heavy chains. Moreover, these cells differentiated by an application of MyoD-IT fused to myotubes with high efficiency through co-culturing with mouse C2C12 myoblasts. Because internalized proteins can be degraded in cells without altering the genome, the myogenic differentiation of hASCs using MyoD-IT would be a safe and clinically applicable method
Synaptic network activity induces neuronal differentiation of adult hippocampal precursor cells through BDNF signaling

Directory of Open Access Journals (Sweden)

Harish Babu

2009-09-01

Full Text Available Adult hippocampal neurogenesis is regulated by activity. But how do neural precursor cells in the hippocampus respond to surrounding network activity and translate increased neural activity into a developmental program? Here we show that long-term potential (LTP-like synaptic activity within a cellular network of mature hippocampal neurons promotes neuronal differentiation of newly generated cells. In co-cultures of precursor cells with primary hippocampal neurons, LTP-like synaptic plasticity induced by addition of glycine in Mg2+-free media for 5 min, produced synchronous network activity and subsequently increased synaptic strength between neurons. Furthermore, this synchronous network activity led to a significant increase in neuronal differentiation from the co-cultured neural precursor cells. When applied directly to precursor cells, glycine and Mg2+-free solution did not induce neuronal differentiation. Synaptic plasticity-induced neuronal differentiation of precursor cells was observed in the presence of GABAergic neurotransmission blockers but was dependent on NMDA-mediated Ca2+ influx. Most importantly, neuronal differentiation required the release of brain-derived neurotrophic factor (BDNF from the underlying substrate hippocampal neurons as well as TrkB receptor phosphorylation in precursor cells. This suggests that activity-dependent stem cell differentiation within the hippocampal network is mediated via synaptically evoked BDNF signaling.
Molecular Mechanisms in Exercise-Induced Cardioprotection

Directory of Open Access Journals (Sweden)

Saeid Golbidi

2011-01-01

Full Text Available Physical inactivity is increasingly recognized as modifiable behavioral risk factor for cardiovascular diseases. A partial list of proposed mechanisms for exercise-induced cardioprotection include induction of heat shock proteins, increase in cardiac antioxidant capacity, expression of endoplasmic reticulum stress proteins, anatomical and physiological changes in the coronary arteries, changes in nitric oxide production, adaptational changes in cardiac mitochondria, increased autophagy, and improved function of sarcolemmal and/or mitochondrial ATP-sensitive potassium channels. It is currently unclear which of these protective mechanisms are essential for exercise-induced cardioprotection. However, most investigations focus on sarcolemmal KATP channels, NO production, and mitochondrial changes although it is very likely that other mechanisms may also exist. This paper discusses current information about these aforementioned topics and does not consider potentially important adaptations within blood or the autonomic nervous system. A better understanding of the molecular basis of exercise-induced cardioprotection will help to develop better therapeutic strategies.
Exercise-induced phospho-proteins in skeletal muscle

DEFF Research Database (Denmark)

Deshmukh, A S; Hawley, J A; Zierath, J R

2008-01-01

Efforts to identify exercise-induced signaling events in skeletal muscle have been influenced by ground-breaking discoveries in the insulin action field. Initial discoveries demonstrating that exercise enhances insulin sensitivity raised the possibility that contraction directly modulates insulin...... receptor signaling events. Although the acute effects of exercise on glucose metabolism are clearly insulin-independent, the canonical insulin signaling cascade has been used as a framework by investigators in an attempt to resolve the mechanisms by which muscle contraction governs glucose metabolism....... This review focuses on recent advances in our understanding of exercise-induced signaling pathways governing glucose metabolism in skeletal muscle. Particular emphasis will be placed on the characterization of AS160, a novel Akt substrate that plays a role in the regulation of glucose transport....
AMPKα is essential for acute exercise-induced gene responses but not for exercise training-induced adaptations in mouse skeletal muscle

DEFF Research Database (Denmark)

Fentz, Joachim; Kjøbsted, Rasmus; Maag Kristensen, Caroline

2015-01-01

-induced increases in exercise capacity and expression of metabolic proteins as well as acute exercise-induced gene regulation would be compromised in AMPKα1 and -α2 muscle-specific double knockout (mdKO) mice. An acute bout of exercise increased skeletal muscle mRNA content of cytochrome C oxidase subunit I......, glucose transporter 4 and VEGF in an AMPK-dependent manner, while cluster of differentiation 36 and fatty acid transport protein 1 mRNA content increased similarly in AMPKα wild type (WT) and mdKO mice. During four weeks of voluntary running wheel exercise training, the AMPKα mdKO mice ran less than WT...
Myogenic Differentiation from MYOGENIN-Mutated Human iPS Cells by CRISPR/Cas9

Directory of Open Access Journals (Sweden)

Koki Higashioka

2017-01-01

Full Text Available It is well known that myogenic regulatory factors encoded by the Myod1 family of genes have pivotal roles in myogenesis, with partially overlapping functions, as demonstrated for the mouse embryo. Myogenin-mutant mice, however, exhibit severe myogenic defects without compensation by other myogenic factors. MYOGENIN might be expected to have an analogous function in human myogenic cells. To verify this hypothesis, we generated MYOGENIN-mutated human iPS cells by using CRISPR/Cas9 genome-editing technology. Our results suggest that MYOD1-independent or MYOD1-dependent mechanisms can compensate for the loss of MYOGENIN and that these mechanisms are likely to be crucial for regulating skeletal muscle differentiation and formation.

Refractory episodic vertigo: role of intratympanic gentamicin and vestibular evoked myogenic potentials,

Directory of Open Access Journals (Sweden)

Erika Celis-Aguilar

Full Text Available Abstract Introduction: Even today, the treatment of intractable vertigo remains a challenge. Vestibular ablation with intratympanic gentamicin stands as a good alternative in the management of refractory vertigo patients. Objective: To control intractable vertigo through complete saccular and horizontal canal vestibular ablation with intratympanic gentamicin treatment. Methods: Patients with refractory episodic vertigo were included. The inclusion criteria were: unilateral ear disease, moderate to profound sensorineural hearing loss, and failure to other treatments. Included patients underwent 0.5-0.8 mL of gentamicin intratympanic application at a 30 mg/mL concentration. Vestibular ablation was confirmed by the absence of response on cervical vestibular evoked myogenic potentials and no response on caloric tests. Audiometry, electronystagmography with iced water, and vestibular evoked myogenic potentials were performed in all patients. Results: Ten patients were included; nine patients with Meniere's disease and one patient with (late onset delayed hydrops. Nine patients showed an absent response on vestibular evoked myogenic potentials and no response on caloric tests. The only patient with low amplitude on cervical vestibular evoked myogenic potentials had vertigo recurrence. Vertigo control was achieved in 90% of the patients. One patient developed hearing loss >30 dB. Conclusions: Cervical vestibular evoked myogenic potentials confirmed vestibular ablation in patients treated with intratympanic gentamicin. High-grade vertigo control was due to complete saccular and horizontal canal ablation (no response to iced water in electronystagmography and no response on cervical vestibular evoked myogenic potentials.
Influence of pre-exercise muscle glycogen content on exercise-induced transcriptional regulation of metabolic genes

DEFF Research Database (Denmark)

Pilegaard, Henriette; Keller, Charlotte; Steensberg, Adam

2002-01-01

Transcription of metabolic genes is transiently induced during recovery from exercise in skeletal muscle of humans. To determine whether pre-exercise muscle glycogen content influences the magnitude and/or duration of this adaptive response, six male subjects performed one-legged cycling exercise...... to lower muscle glycogen content in one leg and then, the following day, completed 2.5 h low intensity two-legged cycling exercise. Nuclei and mRNA were isolated from biopsies obtained from the vastus lateralis muscle of the control and reduced glycogen (pre-exercise glycogen = 609 +/- 47 and 337 +/- 33...... mmol kg(-1) dry weight, respectively) legs before and after 0, 2 and 5 h of recovery. Exercise induced a significant (P glycogen leg only. Although PDK4...
Optical precursors with tunneling-induced transparency in asymmetric quantum wells

International Nuclear Information System (INIS)

Peng Yandong; Qi Yihong; Yao Haifeng; Niu Yueping; Gong Shangqing

2011-01-01

A scheme for separating optical precursors from a square-modulated laser pulse through an asymmetric double Al x Ga 1-x As/GaAs quantum-well structure via resonant tunneling is proposed. Destructive interference inhibits linear absorption, and a tunneling-induced transparency (TIT) window appears with normal dispersion, which delays the main pulse; then optical precursors are obtained. Due to resonant tunneling, constructive interference for nonlinear susceptibility is created. The enhanced dispersion in a narrow TIT window is about one order of magnitude larger than that of the linear case. In this case, the main pulse is much delayed and the precursor signals are easier to obtain. Moreover, the main pulse builds up due to the gain introduced by the enhanced cross-nonlinearity.
Making muscles "stronger": exercise, nutrition, drugs.

Science.gov (United States)

Aagaard, P

2004-06-01

As described in this review, maximal muscle strength is strongly influenced by resistive-types of exercise, which induce adaptive changes in both neuromuscular function and muscle morphology. Further, timed intake of protein in conjunction with resistance training elicit greater strength and muscle size gains than resistance training alone. Creatine supplementation amplifies the hypertrophic response to resistance training, although some individuals may not respond positively. Locally produced muscle growth factors are upregulated during creatine supplementation, which contributes to increase the responsiveness of muscle cells to intensive training stimuli. Usage of anabolic steroids boosts muscle hypertrophy beyond inherent genetical limits, not only by increasing the DNA transcription rate for myofibrillar proteins but also by increasing the nucleus-to-cytoplasm ratio due to accelerated activation of myogenic satellite cells. However, severe tissue damaging effects exist with anabolic steroids, some of which are irreversible.
Adult medulloblastoma with myogenic differentiation

Directory of Open Access Journals (Sweden)

Xia-ling ZHANG

2015-09-01

Full Text Available Objective To explore the clinicopathological features of adult medulloblastoma with myogenic differentiation and to discuss clinicopathological differentiations from relevant tumors, so as to improve the ability of diagnosing and differentiating this kind of tumor. Methods The clinical manifestations, imaging, pathological features and immunohistochemical features of one case of adult medulloblastoma with myogenic differentiation were analyzed, and related literatures were reviewed. Results A 32-year-old female patient presented with repeated distortion of mouth and facial numbness for over 6 years. T1WI showed a mixed-signal lesion in the cerebellar vermis and dorsal part of brainstem, and protruded toward the fourth ventricle. Enhanced T1WI showed a round strengthened nodule in the lesion. During operation, it was seen that the tumor arised in cerebellar vermis, projected into the fourth ventricle and invaded brainstem. On microscopy examination, it was found that oval nuclei tumor cells were distributed in sheet or scattered patterns, and neuroblastic rosettes were observed. Abundant and eosinophilic cytoplasm, eccentrically placed and atypical nuclei containing hyperchromatic chromatin or prominent nucleoli in the tumor could be displayed. Mitoses were frequently seen. The tumor also presented with fresh and old hemorrhage in some place. Immunohistochemical staining showed that tumor cells were diffusely positive for integrase interactor 1 (INI1, synaptophysin (Syn, chromogranin A (CgA, human internexin neuronal intermediate filament protein α (INα, neurofilament protein (NF, Nestin (Nes, β-catenin and P53, and partly positive for desmin (Des, neuronal nuclei (NeuN and S-100 protein (S-100, but negative for glial fibrillary acidic protein (GFAP, oligodendrocyte transcription factor-2 (Olig-2, CD99, pan cytokeratin (PCK, epithelial membrane antigen (EMA, MyoD1, myogenin, muscle-specific actin (MSA and smooth muscle actin (SMA. Ki-67
Exercise and chemotherapy-induced amenorrhea.

Science.gov (United States)

Mathis, Katlynn M; Sturgeon, Kathleen M; Winkels, Renate M; Wiskemann, Joachim; Williams, Nancy I; Schmitz, Kathryn

2018-07-01

Chemotherapy-induced amenorrhea (CIA) is the temporary or permanent loss of menses experienced by premenopausal women undergoing chemotherapy treatment for cancer. Two possible mechanisms through which chemotherapy induces CIA have been identified: systemic endothelial dysfunction, resulting in decreased blood flow to the ovaries, and increased oxidative stress within the ovaries, both of which are proposed to lead to apoptosis of follicles. Endothelial dysfunction in ovarian arteries in women undergoing or who have undergone chemotherapy treatment is characterized by prothrombotic changes and thickening of the vascular wall. These changes result in occlusion of the blood vessels. Oxidative stress is increased and antioxidants decreased in the ovaries secondary to chemotherapy drugs, specifically cyclophosphamide. It is hypothesized that low to moderate intensity aerobic exercise during chemotherapy may prevent these changes and lessen the risk for developing CIA in premenopausal women. Low to moderate intensity aerobic exercise has been shown to improve endothelial function and blood flow in patients with cardiovascular disease-a disease state characterized by endothelial dysfunction and for which patients who have undergone chemotherapy are at increased risk. In mice, moderate intensity aerobic exercise has been shown to decrease the amount of oxidative stress within the ovaries, and in humans, chronic aerobic exercise has been shown to increase antioxidant production systemically. This hypothesis should be tested in both a mouse model, using sedentary and exercising mice treated with chemotherapy drugs that commonly result in CIA, as well as a human model to determine the effects of low to moderate intensity aerobic exercise on ovarian function in premenopausal women undergoing chemotherapy. Copyright © 2018 Elsevier Ltd. All rights reserved.
Refractory episodic vertigo: role of intratympanic gentamicin and vestibular evoked myogenic potentials.

Science.gov (United States)

Celis-Aguilar, Erika; Hinojosa-González, Ramon; Vales-Hidalgo, Olivia; Coutinho-Toledo, Heloisa

Even today, the treatment of intractable vertigo remains a challenge. Vestibular ablation with intratympanic gentamicin stands as a good alternative in the management of refractory vertigo patients. To control intractable vertigo through complete saccular and horizontal canal vestibular ablation with intratympanic gentamicin treatment. Patients with refractory episodic vertigo were included. The inclusion criteria were: unilateral ear disease, moderate to profound sensorineural hearing loss, and failure to other treatments. Included patients underwent 0.5-0.8mL of gentamicin intratympanic application at a 30mg/mL concentration. Vestibular ablation was confirmed by the absence of response on cervical vestibular evoked myogenic potentials and no response on caloric tests. Audiometry, electronystagmography with iced water, and vestibular evoked myogenic potentials were performed in all patients. Ten patients were included; nine patients with Meniere's disease and one patient with (late onset) delayed hydrops. Nine patients showed an absent response on vestibular evoked myogenic potentials and no response on caloric tests. The only patient with low amplitude on cervical vestibular evoked myogenic potentials had vertigo recurrence. Vertigo control was achieved in 90% of the patients. One patient developed hearing loss >30dB. Cervical vestibular evoked myogenic potentials confirmed vestibular ablation in patients treated with intratympanic gentamicin. High-grade vertigo control was due to complete saccular and horizontal canal ablation (no response to iced water in electronystagmography and no response on cervical vestibular evoked myogenic potentials). Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.
Skeletal muscle hypertrophy and regeneration: interplay between the myogenic regulatory factors (MRFs) and insulin-like growth factors (IGFs) pathways.

Science.gov (United States)

Zanou, Nadège; Gailly, Philippe

2013-11-01

Adult skeletal muscle can regenerate in response to muscle damage. This ability is conferred by the presence of myogenic stem cells called satellite cells. In response to stimuli such as injury or exercise, these cells become activated and express myogenic regulatory factors (MRFs), i.e., transcription factors of the myogenic lineage including Myf5, MyoD, myogenin, and Mrf4 to proliferate and differentiate into myofibers. The MRF family of proteins controls the transcription of important muscle-specific proteins such as myosin heavy chain and muscle creatine kinase. Different growth factors are secreted during muscle repair among which insulin-like growth factors (IGFs) are the only ones that promote both muscle cell proliferation and differentiation and that play a key role in muscle regeneration and hypertrophy. Different isoforms of IGFs are expressed during muscle repair: IGF-IEa, IGF-IEb, or IGF-IEc (also known as mechano growth factor, MGF) and IGF-II. MGF is expressed first and is observed in satellite cells and in proliferating myoblasts whereas IGF-Ia and IGF-II expression occurs at the state of muscle fiber formation. Interestingly, several studies report the induction of MRFs in response to IGFs stimulation. Inversely, IGFs expression may also be regulated by MRFs. Various mechanisms are proposed to support these interactions. In this review, we describe the general process of muscle hypertrophy and regeneration and decipher the interactions between the two groups of factors involved in the process.
Low-load high volume resistance exercise stimulates muscle protein synthesis more than high-load low volume resistance exercise in young men.

Directory of Open Access Journals (Sweden)

Nicholas A Burd

Full Text Available BACKGROUND: We aimed to determine the effect of resistance exercise intensity (%1 repetition maximum-1RM and volume on muscle protein synthesis, anabolic signaling, and myogenic gene expression. METHODOLOGY/PRINCIPAL FINDINGS: Fifteen men (21+/-1 years; BMI=24.1+/-0.8 kg/m2 performed 4 sets of unilateral leg extension exercise at different exercise loads and/or volumes: 90% of repetition maximum (1RM until volitional failure (90FAIL, 30% 1RM work-matched to 90%FAIL (30WM, or 30% 1RM performed until volitional failure (30FAIL. Infusion of [ring-13C6] phenylalanine with biopsies was used to measure rates of mixed (MIX, myofibrillar (MYO, and sarcoplasmic (SARC protein synthesis at rest, and 4 h and 24 h after exercise. Exercise at 30WM induced a significant increase above rest in MIX (121% and MYO (87% protein synthesis at 4 h post-exercise and but at 24 h in the MIX only. The increase in the rate of protein synthesis in MIX and MYO at 4 h post-exercise with 90FAIL and 30FAIL was greater than 30WM, with no difference between these conditions; however, MYO remained elevated (199% above rest at 24 h only in 30FAIL. There was a significant increase in AktSer473 at 24h in all conditions (P=0.023 and mTORSer2448 phosphorylation at 4 h post-exercise (P=0.025. Phosporylation of Erk1/2Tyr202/204, p70S6KThr389, and 4E-BP1Thr37/46 increased significantly (P<0.05 only in the 30FAIL condition at 4 h post-exercise, whereas, 4E-BP1Thr37/46 phosphorylation was greater 24 h after exercise than at rest in both 90FAIL (237% and 30FAIL (312% conditions. Pax7 mRNA expression increased at 24 h post-exercise (P=0.02 regardless of condition. The mRNA expression of MyoD and myogenin were consistently elevated in the 30FAIL condition. CONCLUSIONS/SIGNIFICANCE: These results suggest that low-load high volume resistance exercise is more effective in inducing acute muscle anabolism than high-load low volume or work matched resistance exercise modes.
Aging is associated with diminished muscle re-growth and myogenic precursor cell expansion in the early recovery phase after immobility-induced atrophy in human skeletal muscle

DEFF Research Database (Denmark)

Suetta, Charlotte Arneboe; Frandsen, Ulrik; Mackey, Abigail L

2013-01-01

Recovery of skeletal muscle mass from immobilisation-induced atrophy is faster in young than older individuals, yet the cellular mechanisms remain unknown. We examined the cellular and molecular regulation of muscle recovery in young and old human subjects subsequent to 2 weeks of immobility...... expression analysis of key growth and transcription factors associated with local skeletal muscle milieu were performed after 2 weeks immobility (Imm) and following 3 days (+3d) and 4 weeks (+4wks) of re-training. OM demonstrated no detectable gains in MFA (VL muscle) and no increases in number of Pax7......-induced muscle atrophy. Re-training consisted of 4 weeks of supervised resistive exercise in 9 older (OM: 67.3yrs, range 61-74) and 11 young (YM: 24.4yrs, range 21-30) males. Measures of myofiber area (MFA), Pax7-positive satellite cells (SC) associated with type I and type II muscle fibres, as well as gene...
Low intensity exercise training improves skeletal muscle regeneration potential

Directory of Open Access Journals (Sweden)

Tiziana ePietrangelo

2015-12-01

Full Text Available Purpose: The aim of this study was to determine whether 12 days of low-to-moderate exercise training at low altitude (598 m a.s.l. improves skeletal muscle regeneration in sedentary adult women.Methods: Satellite cells were obtained from the vastus lateralis skeletal muscle of seven women before and after this exercise training at low altitude. They were investigated for differentiation aspects, superoxide anion production, antioxidant enzymes, mitochondrial potential variation after a depolarizing insult, intracellular Ca2+ concentrations, and micro (miRNA expression (miR-1, miR-133, miR-206.Results: In these myogenic populations of adult stem cells, those obtained after exercise training, showed increased Fusion Index and intracellular Ca2+ concentrations. This exercise training also generally reduced superoxide anion production in cells (by 12% to 67%, although not in two women, where there was an increase of ~15% along with a reduced superoxide dismutase activity. miRNA expression showed an exercise-induced epigenetic transcription profile that was specific according to the reduced or increased superoxide anion production of the cells. Conclusions: The present study shows that low-to-moderate exercise training at low altitude improves the regenerative capacity of skeletal muscle in adult women. The differentiation of cells was favored by increased intracellular calcium concentration and increased the fusion index. This low-to-moderate training at low altitude also depicted the epigenetic signature of cells.
Mesenchymal Stromal Cells for Sphincter Regeneration: Role of Laminin Isoforms upon Myogenic Differentiation

Science.gov (United States)

Seeger, Tanja; Hart, Melanie; Patarroyo, Manuel; Rolauffs, Bernd; Aicher, Wilhelm K.; Klein, Gerd

2015-01-01

Multipotent mesenchymal stromal cells (MSCs) are well known for their tri-lineage potential and ability to differentiate in vitro into osteogenic, chondrogenic or adipogenic lineages. By selecting appropriate conditions MSCs can also be differentiated in vitro into the myogenic lineage and are therefore a promising option for cell-based regeneration of muscle tissue such as an aged or damaged sphincter muscle. For the differentiation into the myogenic lineage there is still a need to evaluate the effects of extracellular matrix proteins such as laminins (LM) which are crucial for different stem cell types and for normal muscle function. The laminin family consists of 16 functionally different isoforms with LM-211 being the most abundant isoform of adult muscle tissues. In the sphincter tissue a strong expression of the isoforms LM-211/221, LM-411/421 and LM-511/521 can be detected in the different cell layers. Bone marrow-derived MSCs in culture, however, mainly express the isoforms LM-411 and LM-511, but not LM-211. Even after myogenic differentiation, LM-211 can hardly be detected. All laminin isoforms tested (LM-211, LM-411, LM-511 and LM-521) showed a significant inhibition of the proliferation of undifferentiated MSCs but, with the exception of LM-521, they had no influence on the proliferation of MSCs cultivated in myogenic medium. The strongest cellular adhesion of MSCs was to LM-511 and LM-521, whereas LM-211 was only a weakly-adhesive substrate for MSCs. Myogenic differentiation of MSCs even reduced the interaction with LM-211, but it did not affect the interaction with LM-511 and LM-521. Since during normal myogenesis the latter two isoforms are the major laminins surrounding developing myogenic progenitors, α5 chain-containing laminins are recommended for further improvements of myogenic differentiation protocols of MSCs into smooth muscle cells. PMID:26406476
Mesenchymal Stromal Cells for Sphincter Regeneration: Role of Laminin Isoforms upon Myogenic Differentiation.

Directory of Open Access Journals (Sweden)

Tanja Seeger

Full Text Available Multipotent mesenchymal stromal cells (MSCs are well known for their tri-lineage potential and ability to differentiate in vitro into osteogenic, chondrogenic or adipogenic lineages. By selecting appropriate conditions MSCs can also be differentiated in vitro into the myogenic lineage and are therefore a promising option for cell-based regeneration of muscle tissue such as an aged or damaged sphincter muscle. For the differentiation into the myogenic lineage there is still a need to evaluate the effects of extracellular matrix proteins such as laminins (LM which are crucial for different stem cell types and for normal muscle function. The laminin family consists of 16 functionally different isoforms with LM-211 being the most abundant isoform of adult muscle tissues. In the sphincter tissue a strong expression of the isoforms LM-211/221, LM-411/421 and LM-511/521 can be detected in the different cell layers. Bone marrow-derived MSCs in culture, however, mainly express the isoforms LM-411 and LM-511, but not LM-211. Even after myogenic differentiation, LM-211 can hardly be detected. All laminin isoforms tested (LM-211, LM-411, LM-511 and LM-521 showed a significant inhibition of the proliferation of undifferentiated MSCs but, with the exception of LM-521, they had no influence on the proliferation of MSCs cultivated in myogenic medium. The strongest cellular adhesion of MSCs was to LM-511 and LM-521, whereas LM-211 was only a weakly-adhesive substrate for MSCs. Myogenic differentiation of MSCs even reduced the interaction with LM-211, but it did not affect the interaction with LM-511 and LM-521. Since during normal myogenesis the latter two isoforms are the major laminins surrounding developing myogenic progenitors, α5 chain-containing laminins are recommended for further improvements of myogenic differentiation protocols of MSCs into smooth muscle cells.
Zinc promotes proliferation and activation of myogenic cells via the PI3K/Akt and ERK signaling cascade

Energy Technology Data Exchange (ETDEWEB)

Ohashi, Kazuya, E-mail: asuno10k@yahoo.co.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Nagata, Yosuke, E-mail: cynagata@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Wada, Eiji, E-mail: gacchu1@yahoo.co.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Zammit, Peter S., E-mail: peter.zammit@kcl.ac.uk [Randall Division of Cell and Molecular Biophysics, King' s College London, London SE1 1UL (United Kingdom); Shiozuka, Masataka, E-mail: cmuscle@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan); Matsuda, Ryoichi, E-mail: cmatsuda@mail.ecc.u-tokyo.ac.jp [Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo (Japan)

2015-05-01

Skeletal muscle stem cells named muscle satellite cells are normally quiescent but are activated in response to various stimuli, such as injury and overload. Activated satellite cells enter the cell cycle and proliferate to produce a large number of myogenic progenitor cells, and these cells then differentiate and fuse to form myofibers. Zinc is one of the essential elements in the human body, and has multiple roles, including cell growth and DNA synthesis. However, the role of zinc in myogenic cells is not well understood, and is the focus of this study. We first examined the effects of zinc on differentiation of murine C2C12 myoblasts and found that zinc promoted proliferation, with an increased number of cells incorporating EdU, but inhibited differentiation with reduced myogenin expression and myotube formation. Furthermore, we used the C2C12 reserve cell model of myogenic quiescence to investigate the role of zinc on activation of myogenic cells. The number of reserve cells incorporating BrdU was increased by zinc in a dose dependent manner, with the number dramatically further increased using a combination of zinc and insulin. Akt and extracellular signal-regulated kinase (ERK) are downstream of insulin signaling, and both were phosphorylated after zinc treatment. The zinc/insulin combination-induced activation involved the phosphoinositide 3-kinase (PI3K)/Akt and ERK cascade. We conclude that zinc promotes activation and proliferation of myogenic cells, and this activation requires phosphorylation of PI3K/Akt and ERK as part of the signaling cascade. - Highlights: • Zinc has roles for promoting proliferation and inhibition differentiation of C2C12. • Zinc promotes activation of reserve cells. • Insulin and zinc synergize activation of reserve cells. • PI3K/Akt and ERK cascade affect zinc/insulin-mediated activation of reserve cells.
Exercisers achieve greater acute exercise-induced mood enhancement than nonexercisers.

Science.gov (United States)

Hoffman, Martin D; Hoffman, Debi Rufi

2008-02-01

To determine whether a single session of exercise of appropriate intensity and duration for aerobic conditioning has a different acute effect on mood for nonexercisers than regular exercisers. Repeated-measures design. Research laboratory. Adult nonexercisers, moderate exercisers, and ultramarathon runners (8 men, 8 women in each group). Treadmill exercise at self-selected speeds to induce a rating of perceived exertion (RPE) of 13 (somewhat hard) for 20 minutes, preceded and followed by 5 minutes at an RPE of 9 (very light). Profile of Mood States before and 5 minutes after exercise. Vigor increased by a mean +/- standard deviation of 8+/-7 points (95% confidence interval [CI], 5-12) among the ultramarathon runners and 5+/-4 points (95% CI, 2-9) among the moderate exercisers, with no improvement among the nonexercisers. Fatigue decreased by 5+/-6 points (95% CI, 2-8) for the ultramarathon runners and 4+/-4 points (95% CI, 1-7) for the moderate exercisers, with no improvement among the nonexercisers. Postexercise total mood disturbance decreased by a mean of 21+/-16 points (95% CI, 12-29) among the ultramarathon runners, 16+/-10 points (95% CI, 7-24) among the moderate exercisers, and 9+/-13 points (95% CI, 1-18) among the nonexercisers. A single session of moderate aerobic exercise improves vigor and decreases fatigue among regular exercisers but causes no change in these scores for nonexercisers. Although total mood disturbance improves postexercise in exercisers and nonexercisers, regular exercisers have approximately twice the effect as nonexercisers. This limited postexercise mood improvement among nonexercisers may be an important deterrent for persistence with an exercise program.
Engraftment potential of dermal fibroblasts following in vivo myogenic conversion in immunocompetent dystrophic skeletal muscle

Directory of Open Access Journals (Sweden)

Lindsey A Muir

2014-01-01

Full Text Available Autologous dermal fibroblasts (dFbs are promising candidates for enhancing muscle regeneration in Duchenne muscular dystrophy (DMD due to their ease of isolation, immunological compatibility, and greater proliferative potential than DMD satellite cells. We previously showed that mouse fibroblasts, after MyoD-mediated myogenic reprogramming in vivo, engraft in skeletal muscle and supply dystrophin. Assessing the therapeutic utility of this system requires optimization of conversion and transplantation conditions and quantitation of engraftment so that these parameters can be correlated with possible functional improvements. Here, we derived dFbs from transgenic mice carrying mini-dystrophin, transduced them by lentivirus carrying tamoxifen-inducible MyoD, and characterized their myogenic and engraftment potential. After cell transplantation into the muscles of immunocompetent dystrophic mdx4cv mice, tamoxifen treatment drove myogenic conversion and fusion into myofibers that expressed high levels of mini-dystrophin. Injecting 50,000 cells/µl (1 × 106 total cells resulted in a peak of ∼600 mini-dystrophin positive myofibers in tibialis anterior muscle single cross-sections. However, extensor digitorum longus muscles with up to 30% regional engraftment showed no functional improvements; similar limitations were obtained with whole muscle mononuclear cells. Despite the current lack of physiological improvement, this study suggests a viable initial strategy for using a patient-accessible dermal cell population to enhance skeletal muscle regeneration in DMD.
Exercise-induced maximum metabolic rate scaled to body mass by ...

African Journals Online (AJOL)

Exercise-induced maximum metabolic rate scaled to body mass by the fractal ... rate scaling is that exercise-induced maximum aerobic metabolic rate (MMR) is ... muscle stress limitation, and maximized oxygen delivery and metabolic rates.
The rational design of a Au(I) precursor for focused electron beam induced deposition

NARCIS (Netherlands)

Marashdeh, Ali; Tiesma, Thiadrik; van Velzen, Niels J. C.; Harder, Sjoerd; Havenith, Remco W. A.; De Hosson, Jeff T. M.; van Dorp, Willem F.

2017-01-01

Au(I) complexes are studied as precursors for focused electron beam induced processing (FEBIP). FEBIP is an advanced direct-write technique for nanometer-scale chemical synthesis. The stability and volatility of the complexes are characterized to design an improved precursor for pure Au deposition.
Exercise-induced rhabdomyolysis from stationary biking: a case report.

Science.gov (United States)

Inklebarger, J; Galanis, N; Kirkos, J; Kapetanos, G

2010-10-01

There are several reports concerning exercise and rabdomyolysis. There has been no report in the English literature of exercise induced rabdomyolisis from a stationary bike.A 63-year-old female recreational athlete presented to our hospital seeking treatment for lower back, leg pain and stiffness after exercising on a stationary bicycle one day prior. Blood work showed a raised CK of 38,120 U/L, a myoglobin of 5330 and an AST 495 U/L with normal urea and electrolytes. Urinalysis remained negative. She was admitted for oral and intravenous hydration and fluid balance monitoringThis is a very rare case of rhabdomyolysis due to exercise. This study highlights the difficulties faced by accident and emergency teams in distinguishing delayed onset muscle soreness (DOMS) from exercise-induced rhabdomyolysis, and reinforces the concept that rhabdomyolysis can occur at any level of exercise intensity.
Beneficial effects of neuropeptide galanin on reinstatement of exercise-induced somatic and psychological trauma.

Science.gov (United States)

He, Biao; Fang, Penghua; Guo, Lili; Shi, Mingyi; Zhu, Yan; Xu, Bo; Bo, Ping; Zhang, Zhenwen

2017-04-01

Galanin is a versatile neuropeptide that is distinctly upregulated by exercise in exercise-related tissues. Although benefits from exercise-induced upregulation of this peptide have been identified, many issues require additional exploration. This Review summarizes the information currently available on the relationship between galanin and exercise-induced physical and psychological damage. On the one hand, body movement, exercise damage, and exercise-induced stress and pain significantly increase local and circulatory galanin levels. On the other hand, galanin plays an exercise-protective role to inhibit the flexor reflex and prevent excessive movement of skeletal muscles through enhancing response threshold and reducing acetylcholine release. Additionally, elevated galanin levels can boost repair of the exercise-induced damage in exercise-related tissues, including peripheral nerve, skeletal muscle, blood vessel, skin, bone, articulation, and ligament. Moreover, elevated galanin levels may serve as effective signals to buffer sport-induced stress and pain via inhibiting nociceptive signal transmission and enhancing pain threshold. This Review deepens our understanding of the profitable roles of galanin in exercise protection, exercise injury repair, and exercise-induced stress and pain. Galanin and its agonists may be used to develop a novel preventive and therapeutic strategy to prevent and treat exercise-induced somatic and psychological trauma. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

A Comparative Study to Evaluate Myogenic Differentiation Potential of Human Chorion versus Umbilical Cord Blood-derived Mesenchymal Stem Cells.

Science.gov (United States)

Bana, Nikoo; Sanooghi, Davood; Soleimani, Mansoureh; Hayati Roodbari, Nasim; Alavi Moghaddam, Sepideh; Joghataei, Mohammad Taghi; Sayahpour, Forough Azam; Faghihi, Faezeh

2017-08-01

Musculodegenerative diseases threaten the life of many patients in the world. Since drug administration is not efficient in regeneration of damaged tissues, stem cell therapy is considered as a good strategy to restore the lost cells. Since the efficiency of myogenic differentiation potential of human Chorion- derived Mesenchymal Stem Cells (C-MSCs) has not been addressed so far; we set out to evaluate myogenic differentiation property of these cells in comparison with Umbilical Cord Blood- derived Mesenchymal Stem Cells (UCB-MSCs) in the presence of 5-azacytidine. To do that, neonate placenta Umbilical Cord Blood were transferred to the lab. After characterization of the isolated cells using flowcytometry and multilineage differentiation capacity, the obtained Mesenchymal Stem Cells were cultured in DMEM/F12 supplemented with 2% FBS and 10μM of 5-azacytidine to induce myogenic differentiation. Real-time PCR and immunocytochemistry were used to assess the myogenic properties of the cells. Our data showed that C-MSCs and UCB-MSCs were spindle shape in morphology. They were positive for CD90, CD73 and CD44 antigens, and negative for hematopoietic markers. They also differentiated into osteoblast and adipoblast lineages. Real-time PCR results showed that the cells could express MyoD, desmin and α-MHC at the end of the first week (P<0.05). No significant upregulation was detected in the expression of GATA-4 in both groups. Immunocytochemical staining revealed the expression of Desmin, cTnT and α-MHC. Results showed that these cells are potent to differentiate into myoblast- like cells. An upregulation in the expression of some myogenic markers (desmin, α- MHC) was observed in C-MSCs in comparison with UCB-MSCs. Copyright © 2017. Published by Elsevier Ltd.
Role of Coronary Myogenic Response in Pressure-Flow Autoregulation in Swine: A Meta-Analysis With Coronary Flow Modeling

OpenAIRE

Gregory M. Dick; Ravi Namani; Bhavesh Patel; Ghassan S. Kassab

2018-01-01

Myogenic responses (pressure-dependent contractions) of coronary arterioles play a role in autoregulation (relatively constant flow vs. pressure). Publications on myogenic reactivity in swine coronaries vary in caliber, analysis, and degree of responsiveness. Further, data on myogenic responses and autoregulation in swine have not been completely compiled, compared, and modeled. Thus, it has been difficult to understand these physiological phenomena. Our purpose was to: (a) analyze myogenic d...
Exercise-induced metallothionein expression in human skeletal muscle fibres

DEFF Research Database (Denmark)

Penkowa, Milena; Keller, Pernille; Keller, Charlotte

2005-01-01

in both type I and II muscle fibres. This is the first report demonstrating that MT-I + II are significantly induced in human skeletal muscle fibres following exercise. As MT-I + II are antioxidant factors that protect various tissues during pathological conditions, the MT-I + II increases post exercise......Exercise induces free oxygen radicals that cause oxidative stress, and metallothioneins (MTs) are increased in states of oxidative stress and possess anti-apoptotic effects. We therefore studied expression of the antioxidant factors metallothionein I and II (MT-I + II) in muscle biopsies obtained...... in response to 3 h of bicycle exercise performed by healthy men and in resting controls. Both MT-I + II proteins and MT-II mRNA expression increased significantly in both type I and II muscle fibres after exercise. Moreover, 24 h after exercise the levels of MT-II mRNA and MT-I + II proteins were still highly...
Exercise-Induced Oxidative Stress Responses in the Pediatric Population

Directory of Open Access Journals (Sweden)

Alexandra Avloniti

2017-01-01

Full Text Available Adults demonstrate an upregulation of their pro- and anti-oxidant mechanisms in response to acute exercise while systematic exercise training enhances their antioxidant capacity, thereby leading to a reduced generation of free radicals both at rest and in response to exercise stress. However, less information exists regarding oxidative stress responses and the underlying mechanisms in the pediatric population. Evidence suggests that exercise-induced redox perturbations may be valuable in order to monitor exercise-induced inflammatory responses and as such training overload in children and adolescents as well as monitor optimal growth and development. The purpose of this review was to provide an update on oxidative stress responses to acute and chronic exercise in youth. It has been documented that acute exercise induces age-specific transient alterations in both oxidant and antioxidant markers in children and adolescents. However, these responses seem to be affected by factors such as training phase, training load, fitness level, mode of exercise etc. In relation to chronic adaptation, the role of training on oxidative stress adaptation has not been adequately investigated. The two studies performed so far indicate that children and adolescents exhibit positive adaptations of their antioxidant system, as adults do. More studies are needed in order to shed light on oxidative stress and antioxidant responses, following acute exercise and training adaptations in youth. Available evidence suggests that small amounts of oxidative stress may be necessary for growth whereas the transition to adolescence from childhood may promote maturation of pro- and anti-oxidant mechanisms. Available evidence also suggests that obesity may negatively affect basal and exercise-related antioxidant responses in the peripubertal period during pre- and early-puberty.
Exercise does not protect against MPTP-induced neurotoxicity in BDNF haploinsufficient mice.

Directory of Open Access Journals (Sweden)

Kim M Gerecke

Full Text Available Exercise has been demonstrated to potently protect substantia nigra pars compacta (SN dopaminergic neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP-induced neurotoxicity. One mechanism proposed to account for this neuroprotection is the upregulation of neurotrophic factors. Several neurotrophic factors, including Brain Derived Neurotrophic Factor (BDNF, have been shown to upregulate in response to exercise. In order to determine if exercise-induced neuroprotection is dependent upon BDNF, we compared the neuroprotective effects of voluntary exercise in mice heterozygous for the BDNF gene (BDNF+/- with strain-matched wild-type (WT mice. Stereological estimates of SNpc DA neurons from WT mice allowed 90 days exercise via unrestricted running demonstrated complete protection against the MPTP-induced neurotoxicity. However, BDNF+/- mice allowed 90 days of unrestricted exercise were not protected from MPTP-induced SNpc DA neuron loss. Proteomic analysis comparing SN and striatum from 90 day exercised WT and BDNF+/- mice showed differential expression of proteins related to energy regulation, intracellular signaling and trafficking. These results suggest that a full genetic complement of BDNF is critical for the exercise-induced neuroprotection of SNpc DA neurons.
Food-Dependent, Exercise-Induced Anaphylaxis: Diagnosis and Management in the Outpatient Setting.

Science.gov (United States)

Feldweg, Anna M

Food-dependent, exercise-induced anaphylaxis is a disorder in which anaphylaxis develops most predictably during exercise, when exercise takes place within a few hours of ingesting a specific food. IgE to that food should be demonstrable. It is the combination of the food and exercise that precipitates attacks, whereas the food and exercise are each tolerated independently. Recently, it was demonstrated that exercise is not essential for the development of symptoms, and that if enough of the culprit food is ingested, often with additional augmentation factors, such as alcohol or acetylsalicylic acid, symptoms can be induced at rest in the challenge setting. Thus, food-dependent, exercise-induced anaphylaxis appears to be more correctly characterized as a food allergy syndrome in which symptoms develop only in the presence of various augmentation factors, with exercise being the primary one. However, additional factors are not usually present when the patient exercises normally, so ongoing investigation is needed into the physiologic and cellular changes that occur during exercise to facilitate food-induced anaphylaxis. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
INFLUENCE OF DANCE TRAINING ON SACCULOCOLLIC PATHWAY: VESTIBULAR EVOKED MYOGENIC POTENTIALS (VEMP) AS AN OBJECTIVE TOOL

OpenAIRE

Swathi; Sathish Kumar

2013-01-01

ABSTRACT : Auditory system is shaped by experience and training. Training (s ensory experience) induces neurophysiologic changes & plasticity in normal hearing individuals, hearing loss patients, hearing aid users and cochlear implanted subjects. Not only speech stimulus, but music also brings about functional and structural organi zation of the brain in musician compared to non - musicians. The Vestibular evoked myogenic potentials (VEMP) are a biphasic in...
Analysis of interaction between TGF and the myogenic response in renal blood flow autoregulation

DEFF Research Database (Denmark)

Feldberg, R; Colding-Jørgensen, M; Holstein-Rathlou, N H

1995-01-01

. The contribution of TGF to smooth muscle activity is assumed to be a linear function of the glomerular capillary pressure. The results show that the myogenic response plays an important role in renal blood flow autoregulation. Without a myogenic response, mechanisms such as TGF that are localized in the distal......The present study investigates the interaction between the tubuloglomerular feedback (TGF) response and the myogenic mechanism by use of a mathematical model. The two control mechanisms are implemented in a spatially distributed model of the rat renal juxtamedullary afferent arteriole. The model...
Exercise reverses metabolic syndrome in high-fat diet-induced obese rats.

Science.gov (United States)

Touati, Sabeur; Meziri, Fayçal; Devaux, Sylvie; Berthelot, Alain; Touyz, Rhian M; Laurant, Pascal

2011-03-01

Chronic consumption of a high-fat diet induces obesity. We investigated whether exercise would reverse the cardiometabolic disorders associated with obesity without it being necessary to change from a high- to normal-fat diet. Sprague-Dawley rats were placed on a high-fat (HFD) or control diet (CD) for 12 wk. HFD rats were then divided into four groups: sedentary HFD (HFD-S), exercise trained (motor treadmill for 12 wk) HFD (HFD-Ex), modified diet (HFD to CD; HF/CD-S), and exercise trained with modified diet (HF/CD-Ex). Cardiovascular risk parameters associated with metabolic syndrome were measured, and contents of aortic Akt, phospho-Akt at Ser (473), total endothelial nitric oxide synthase (eNOS), and phospho-eNOS at Ser (1177) were determined by Western blotting. Chronic consumption of HFD induced a metabolic syndrome. Exercise and dietary modifications reduced adiposity, improved glucose and insulin levels and plasma lipid profile, and exerted an antihypertensive effect. Exercise was more effective than dietary modification in improving plasma levels of thiobarbituric acid-reacting substance and in correcting the endothelium-dependent relaxation to acetylcholine and insulin. Furthermore, independent of the diet used, exercise increased Akt and eNOS phosphorylation. Metabolic syndrome induced by HFD is reversed by exercise and diet modification. It is demonstrated that exercise training induces these beneficial effects without the requirement for dietary modification, and these beneficial effects may be mediated by shear stress-induced Akt/eNOS pathway activation. Thus, exercise may be an effective strategy to reverse almost all the atherosclerotic risk factors linked to obesity, particularly in the vasculature.
Pannexin channels mediate the acquisition of myogenic commitment in C2C12 reserve cells promoted by P2 receptor activation

Science.gov (United States)

Riquelme, Manuel A.; Cea, Luis A.; Vega, José L.; Puebla, Carlos; Vargas, Aníbal A.; Shoji, Kenji F.; Subiabre, Mario; Sáez, Juan C.

2015-01-01

The acquisition of myoblast commitment to the myogenic linage requires rises in intracellular free Ca2+ concentration ([Ca2+]i). Putative cell membrane pathways involved in these [Ca2+]i increments are P2 receptors (P2Rs) as well as connexin (Cx) and/or pannexin (Panx) hemichannels and channels (Cx HChs and Panx Chs), respectively, which are known to permeate Ca2+. Reserve cells (RCs) are uncommitted myoblasts obtained from differentiated C2C12 cell cultures, which acquire commitment upon replating. Regarding these cells, we found that extracellular ATP increases the [Ca2+]i via P2Rs. Moreover, ATP increases the plasma membrane permeability to small molecules and a non-selective membrane current, both of which were inhibited by Cx HCh/Panx1Ch blockers. However, RCs exposed to divalent cation-free saline solution, which is known to activate Cx HChs (but not Panx Chs), did not enhance membrane permeability, thus ruling out the possible involvement of Cx HChs. Moreover, ATP-induced membrane permeability was inhibited with blockers of P2Rs that activate Panx Chs. In addition, exogenous ATP induced the expression of myogenic commitment and increased MyoD levels, which was prevented by the inhibition of P2Rs or knockdown of Panx1 Chs. Similarly, increases in MyoD levels induced by ATP released by RCs were inhibited by Panx Ch/Cx HCh blockers. Myogenic commitment acquisition thus requires a feed-forward mechanism mediated by extracellular ATP, P2Rs, and Panx Chs. PMID:26000275
Exercise-induced arteriovenous intrapulmonary shunting in dogs.

Science.gov (United States)

Stickland, Michael K; Lovering, Andrew T; Eldridge, Marlowe W

2007-08-01

We have previously shown, using contrast echocardiography, that intrapulmonary arteriovenous pathways are inducible in healthy humans during exercise; however, this technique does not allow for determination of arteriovenous vessel size or shunt magnitude. The purpose of this study was to determine whether large-diameter (more than 25 microm) intrapulmonary arteriovenous pathways are present in the dog, and whether exercise recruits these conduits. Through the right forelimb, 10.8 million 25-microm stable isotope-labeled microspheres (BioPAL, Inc., Worcester, MA) were injected either at rest (n = 8) or during high-intensity exercise (6- 8 mph, 10-15% grade, n = 6). Systemic arterial blood was continuously sampled during and for 3 minutes after injection. After euthanasia, tissue samples were obtained from the heart, liver, kidney, and skeletal muscle. In addition, 25- and 50-microm microspheres were infused into four isolated dog lungs that were ventilated and perfused at constant pressures similar to exercise. Blood and tissue samples were commercially analyzed for the presence of microspheres. No microspheres were detected in the arterial blood or tissue samples from resting dogs. In contrast, five of six exercising dogs showed evidence of exercise-induced intrapulmonary arteriovenous shunting, as microspheres were detected in arterial blood and/or tissue. Furthermore, shunt magnitude was calculated to be 1.4 +/- 0.8% of cardiac output (n = 3). Evidence of intrapulmonary arteriovenous anastomoses was also found in three of four isolated lungs. Consistent with previous human findings, these data demonstrate that intrapulmonary arteriovenous pathways are functional in the dog and are recruited with exercise.
Self-selected music-induced reduction of perceived exertion during moderate-intensity exercise does not interfere with post-exercise improvements in inhibitory control.

Science.gov (United States)

Tanaka, Daichi; Tsukamoto, Hayato; Suga, Tadashi; Takenaka, Saki; Hamaoka, Takafumi; Hashimoto, Takeshi; Isaka, Tadao

2018-05-26

Acute aerobic exercise improves inhibitory control (IC). This improvement is often associated with increases in perceived exertion during exercise. However, listening to music during aerobic exercise mitigates an exercise-induced increase in perceived exertion. Thus, it is hypothesized that such effects of music may interfere with exercise-induced improvements in IC. To test this hypothesis, we examined the effect of music on post-exercise IC improvements that were induced by moderate-intensity exercise. Fifteen healthy young men performed cycle ergometer exercise with music or non-music. The exercise was performed using a moderate-intensity of 60% of VO 2 peak for 30 min. The music condition was performed while listening to self-selected music. The non-music condition involved no music. To evaluate IC, the Stroop task was administered before exercise, immediately after exercise, and during the 30-min post-exercise recovery period. The rate of perceived exertion immediately before moderate-intensity exercise completed was significantly lower in music condition than in non-music condition. The IC significantly improved immediately after exercise and during the post-exercise recovery period compared to before exercise in both music and non-music conditions. The post-exercise IC improvements did not significantly differ between the two conditions. These findings indicate that self-selected music-induced mitigation of the increase in perceived exertion during moderate-intensity exercise dose not interfere with exercise-induced improvements in IC. Therefore, we suggest that listening to music may be a beneficial strategy in mitigating the increase in perceived exertion during aerobic exercise without decreasing the positive effects on IC. Copyright © 2018 Elsevier Inc. All rights reserved.
Functional relationships between genes associated with differentiation potential of aged myogenic progenitors

Directory of Open Access Journals (Sweden)

Radhakrishnan Nagarajan

2010-09-01

Full Text Available Aging is accompanied by considerable heterogeneity with possible co-expression of differentiation pathways. The present study investigates the interplay between crucial myogenic, adipogenic and Wnt-related genes orchestrating aged myogenic progenitor differentiation (AMPD using clonal gene expression profiling in conjunction with Bayesian structure learning (BSL techniques. The expression of three myogenic regulatory factor genes (Myogenin, Myf-5, MyoD1, four genes involved in regulating adipogenic potential (C/EBPα, DDIT3, FoxC2, PPARγ, and two genes in the Wnt-signaling pathway (Lrp5, Wnt5a known to influence both differentiation programs were determined across thirty-four clones by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR. Three control genes were used for normalization of the clonal expression data (18S, GAPDH and B2M. Constraint-based BSL techniques, namely (a PC Algorithm, (b Grow-shrink algorithm (GS, and (c Incremental Association Markov Blanket (IAMB were used to model the functional relationships (FRs in the form of acyclic networks from the clonal expression profiles. A novel resampling approach that obviates the need for a user-defined confidence threshold is proposed to identify statistically significant FRs at small sample sizes. Interestingly, the resulting acyclic network consisted of FRs corresponding to myogenic, adipogenic, Wnt-related genes and their interaction. A significant number of these FRs were robust to normalization across the three house-keeping genes and the choice of the BSL technique. The results presented elucidate the delicate balance between differentiation pathways (i.e. myogenic as well as adipogenic and possible cross-talk between pathways in AMPD.
Moderate exercise prevents neurodegeneration in D-galactose-induced aging mice

Directory of Open Access Journals (Sweden)

Li Li

2016-01-01

Full Text Available D-galactose has been widely used in aging research because of its efficacy in inducing senescence and accelerating aging in animal models. The present study investigated the benefits of exercise for preventing neurodegeneration, such as synaptic plasticity, spatial learning and memory abilities, in mouse models of aging. D-galactose-induced aging mice were administered daily subcutaneous injections of D-galactose at the base of the neck for 10 consecutive weeks. Then, the mice were subjected to exercise training by running on a treadmill for 6 days a week. Shortened escape latency in a Morris water maze test indicated that exercise improved learning and memory in aging mice. The ameliorative changes were likely induced by an upregulation of Bcl-2 and brain-derived neurotrophic factor, the repression of apoptosis factors such as Fas and Bax, and an increase in the activity of glucose transporters-1 and 4. The data suggest moderate exercise may retard or inhibit neurodegeneration in D-galactose-induced aging mice.
Role of Coronary Myogenic Response in Pressure-Flow Autoregulation in Swine: A Meta-Analysis With Coronary Flow Modeling

Science.gov (United States)

Dick, Gregory M.; Namani, Ravi; Patel, Bhavesh; Kassab, Ghassan S.

2018-01-01

Myogenic responses (pressure-dependent contractions) of coronary arterioles play a role in autoregulation (relatively constant flow vs. pressure). Publications on myogenic reactivity in swine coronaries vary in caliber, analysis, and degree of responsiveness. Further, data on myogenic responses and autoregulation in swine have not been completely compiled, compared, and modeled. Thus, it has been difficult to understand these physiological phenomena. Our purpose was to: (a) analyze myogenic data with standard criteria; (b) assign results to diameter categories defined by morphometry; and (c) use our novel multiscale flow model to determine the extent to which ex vivo myogenic reactivity can explain autoregulation in vivo. When myogenic responses from the literature are an input for our model, the predicted coronary autoregulation approaches in vivo observations. More complete and appropriate data are now available to investigate the regulation of coronary blood flow in swine, a highly relevant model for human physiology and disease. PMID:29875686
Role of Coronary Myogenic Response in Pressure-Flow Autoregulation in Swine: A Meta-Analysis With Coronary Flow Modeling

Directory of Open Access Journals (Sweden)

Gregory M. Dick

2018-05-01

Full Text Available Myogenic responses (pressure-dependent contractions of coronary arterioles play a role in autoregulation (relatively constant flow vs. pressure. Publications on myogenic reactivity in swine coronaries vary in caliber, analysis, and degree of responsiveness. Further, data on myogenic responses and autoregulation in swine have not been completely compiled, compared, and modeled. Thus, it has been difficult to understand these physiological phenomena. Our purpose was to: (a analyze myogenic data with standard criteria; (b assign results to diameter categories defined by morphometry; and (c use our novel multiscale flow model to determine the extent to which ex vivo myogenic reactivity can explain autoregulation in vivo. When myogenic responses from the literature are an input for our model, the predicted coronary autoregulation approaches in vivo observations. More complete and appropriate data are now available to investigate the regulation of coronary blood flow in swine, a highly relevant model for human physiology and disease.
The production of fluorescent transgenic trout to study in vitro myogenic cell differentiation

Directory of Open Access Journals (Sweden)

Rescan Pierre-Yves

2010-05-01

Full Text Available Abstract Background Fish skeletal muscle growth involves the activation of a resident myogenic stem cell population, referred to as satellite cells, that can fuse with pre-existing muscle fibers or among themselves to generate a new fiber. In order to monitor the regulation of myogenic cell differentiation and fusion by various extrinsic factors, we generated transgenic trout (Oncorhynchus mykiss carrying a construct containing the green fluorescent protein reporter gene driven by a fast myosin light chain 2 (MlC2f promoter, and cultivated genetically modified myogenic cells derived from these fish. Results In transgenic trout, green fluorescence appeared in fast muscle fibers as early as the somitogenesis stage and persisted throughout life. Using an in vitro myogenesis system we observed that satellite cells isolated from the myotomal muscle of transgenic trout expressed GFP about 5 days post-plating as they started to fuse. GFP fluorescence persisted subsequently in myosatellite cell-derived myotubes. Using this in vitro myogenesis system, we showed that the rate of muscle cell differentiation was strongly dependent on temperature, one of the most important environmental factors in the muscle growth of poikilotherms. Conclusions We produced MLC2f-gfp transgenic trout that exhibited fluorescence in their fast muscle fibers. The culture of muscle cells extracted from these trout enabled the real-time monitoring of myogenic differentiation. This in vitro myogenesis system could have numerous applications in fish physiology to evaluate the myogenic activity of circulating growth factors, to test interfering RNA and to assess the myogenic potential of fish mesenchymal stem cells. In ecotoxicology, this system could be useful to assess the impact of environmental factors and marine pollutants on fish muscle growth.
An increase in the number of admitted patients with exercise-induced rhabdomyolysis.

Science.gov (United States)

Aalborg, Christian; Rød-Larsen, Cecilie; Leiro, Ingjerd; Aasebø, Willy

2016-10-01

Rhabdomyolysis may lead to serious complications, and treatment is both time-consuming and costly. The condition can be caused by many factors, including intense exercise. The purpose of this study was to investigate whether the number of hospitalisations due to exercise-induced rhabdomyolysis has changed in recent years. We describe the disease course in hospitalised patients, and compare disease course in individuals with exercise-induced rhabdomyolysis and rhabdomyolysis due to other causes. The study is a systematic review of medical records from Akershus University Hospital for the years 2008 and 2011 – 14. All hospitalised patients with diagnostic codes M62.8, M62.9 and T79.6 and creatine kinase levels > 5 000 IU/l were included. The cause of the rhabdomyolysis was recorded in addition to patient characteristics and the results of various laboratory tests. Of 161 patients who were hospitalised with rhabdomyolysis during the study period, 44 cases (27 %) were classified as exercise-induced. In 2008 there were no admissions due to exercise-induced rhabdomyolysis; in 2011 and 2012 there were six and four admissions respectively, while in 2014 there were 22. This gives an estimated incidence of 0.8/100 000 in 2012 and 4.6/100 000 in 2014. Strength-training was the cause of hospitalisation in 35 patients (80 % of the exercise-induced cases). Three patients (7 % of the exercise-induced cases) had transient stage 1 kidney injury, but there were no cases with stage 2 or stage 3 injury. By comparison, 52 % of patients with rhabdomyolysis due to another cause had kidney injury, of which 28 % was stage 2 or 3. The number of persons hospitalised with exercise-induced rhabdomyolysis has increased four-fold from 2011 to 2014, possibly due to changes in exercise habits in the population. None of the patients with exercise-induced rhabdomyolysis had serological signs of kidney injury upon hospital discharge.
Dynamic clustering and dispersion of lipid rafts contribute to fusion competence of myogenic cells

Energy Technology Data Exchange (ETDEWEB)

Mukai, Atsushi [Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 36-3 Gengo, Morioka, Oobu, Aichi 474-8522 (Japan); Kurisaki, Tomohiro [Department of Growth Regulation, Institute for Frontier Medical Sciences, Kyoto University, 53 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto 606-8507 (Japan); Sato, Satoshi B. [Research Center for Low Temperature and Material Sciences, Kyoto University, Yoshida-honmachi, Kyoto 606-8501 (Japan); Kobayashi, Toshihide [Lipid Biology Laboratory, Discovery Research Institute, RIKEN, Wako, Saitama 351-0198 (Japan); Kondoh, Gen [Laboratory of Animal Experiments for Regeneration, Institute for Frontier Medical Sciences, Kyoto University, 53 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto 606-8507 (Japan); Hashimoto, Naohiro, E-mail: nao@nils.go.jp [Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 36-3 Gengo, Morioka, Oobu, Aichi 474-8522 (Japan)

2009-10-15

Recent research indicates that the leading edge of lamellipodia of myogenic cells (myoblasts and myotubes) contains presumptive fusion sites, yet the mechanisms that render the plasma membrane fusion-competent remain largely unknown. Here we show that dynamic clustering and dispersion of lipid rafts contribute to both cell adhesion and plasma membrane union during myogenic cell fusion. Adhesion-complex proteins including M-cadherin, {beta}-catenin, and p120-catenin accumulated at the leading edge of lamellipodia, which contains the presumptive fusion sites of the plasma membrane, in a lipid raft-dependent fashion prior to cell contact. In addition, disruption of lipid rafts by cholesterol depletion directly prevented the membrane union of myogenic cell fusion. Time-lapse recording showed that lipid rafts were laterally dispersed from the center of the lamellipodia prior to membrane fusion. Adhesion proteins that had accumulated at lipid rafts were also removed from the presumptive fusion sites when lipid rafts were laterally dispersed. The resultant lipid raft- and adhesion complex-free area at the leading edge fused with the opposing plasma membrane. These results demonstrate a key role for dynamic clustering/dispersion of lipid rafts in establishing fusion-competent sites of the myogenic cell membrane, providing a novel mechanistic insight into the regulation of myogenic cell fusion.
Dynamic clustering and dispersion of lipid rafts contribute to fusion competence of myogenic cells

International Nuclear Information System (INIS)

Mukai, Atsushi; Kurisaki, Tomohiro; Sato, Satoshi B.; Kobayashi, Toshihide; Kondoh, Gen; Hashimoto, Naohiro

2009-01-01

Recent research indicates that the leading edge of lamellipodia of myogenic cells (myoblasts and myotubes) contains presumptive fusion sites, yet the mechanisms that render the plasma membrane fusion-competent remain largely unknown. Here we show that dynamic clustering and dispersion of lipid rafts contribute to both cell adhesion and plasma membrane union during myogenic cell fusion. Adhesion-complex proteins including M-cadherin, β-catenin, and p120-catenin accumulated at the leading edge of lamellipodia, which contains the presumptive fusion sites of the plasma membrane, in a lipid raft-dependent fashion prior to cell contact. In addition, disruption of lipid rafts by cholesterol depletion directly prevented the membrane union of myogenic cell fusion. Time-lapse recording showed that lipid rafts were laterally dispersed from the center of the lamellipodia prior to membrane fusion. Adhesion proteins that had accumulated at lipid rafts were also removed from the presumptive fusion sites when lipid rafts were laterally dispersed. The resultant lipid raft- and adhesion complex-free area at the leading edge fused with the opposing plasma membrane. These results demonstrate a key role for dynamic clustering/dispersion of lipid rafts in establishing fusion-competent sites of the myogenic cell membrane, providing a novel mechanistic insight into the regulation of myogenic cell fusion.

Dual role of delta-like 1 homolog (DLK1) in skeletal muscle development and adult muscle regeneration

DEFF Research Database (Denmark)

Andersen, Ditte Caroline; Laborda, Jorge; Baladron, Victoriano

2013-01-01

skeletal muscle regeneration by substantial enhancement of the myogenic program and muscle function, possibly by means of an increased number of available myogenic precursor cells. By contrast, Dlk1 fails to alter the adipogenic commitment of muscle-derived progenitors in vitro, as well as intramuscular......Muscle development and regeneration is tightly orchestrated by a specific set of myogenic transcription factors. However, factors that regulate these essential myogenic inducers remain poorly described. Here, we show that delta-like 1 homolog (Dlk1), an imprinted gene best known for its ability...... fat deposition during in vivo regeneration. Collectively, our results suggest a novel and surprising dual biological function of DLK1 as an enhancer of muscle development, but as an inhibitor of adult muscle regeneration....
Characterization of the Methylation Status of Pax7 and Myogenic Regulator Factors in Cell Myogenic Differentiation.

Science.gov (United States)

Chao, Zhe; Zheng, Xin-Li; Sun, Rui-Ping; Liu, Hai-Long; Huang, Li-Li; Cao, Zong-Xi; Deng, Chang-Yan; Wang, Feng

2016-07-01

Epigenetic processes in the development of skeletal muscle have been appreciated for over a decade. DNA methylation is a major epigenetic modification important for regulating gene expression and suppressing spurious transcription. Up to now, the importance of epigenetic marks in the regulation of Pax7 and myogenic regulatory factors (MRFs) expression is far less explored. In the present study, semi-quantitative the real-time polymerase chain reaction (RT-PCR) analyses showed MyoD and Myf5 were expressed in activated and quiescent C2C12 cells. MyoG was expressed in a later stage of myogenesis. Pax7 was weakly expressed in differentiated C2C12 cells. To further understand the regulation of expression of these genes, the DNA methylation status of Pax7, MyoD, and Myf5 was determined by bisulfite sequencing PCR. During the C2C12 myoblasts fusion process, the changes of promoter and exon 1 methylation of Pax7, MyoD, and Myf5 genes were observed. In addition, an inverse relationship of low methylation and high expression was found. These results suggest that DNA methylation may be an important mechanism regulating Pax7 and MRFs transcription in cell myogenic differentiation.
Reporter-Based Isolation of Developmental Myogenic Progenitors

Directory of Open Access Journals (Sweden)

Eyemen Kheir

2018-04-01

Full Text Available The formation and activity of mammalian tissues entail finely regulated processes, involving the concerted organization and interaction of multiple cell types. In recent years the prospective isolation of distinct progenitor and stem cell populations has become a powerful tool in the hands of developmental biologists and has rendered the investigation of their intrinsic properties possible. In this protocol, we describe how to purify progenitors with different lineage history and degree of differentiation from embryonic and fetal skeletal muscle by fluorescence-activated cell sorting (FACS. The approach takes advantage of a panel of murine strains expressing fluorescent reporter genes specifically in the myogenic progenitors. We provide a detailed description of the dissection procedures and of the enzymatic dissociation required to maximize the yield of mononucleated cells for subsequent FACS-based purification. The procedure takes ~6–7 h to complete and allows for the isolation and the subsequent molecular and phenotypic characterization of developmental myogenic progenitors.
Exercise-induced circulating extracellular vesicles protect against cardiac ischemia-reperfusion injury.

Science.gov (United States)

Bei, Yihua; Xu, Tianzhao; Lv, Dongchao; Yu, Pujiao; Xu, Jiahong; Che, Lin; Das, Avash; Tigges, John; Toxavidis, Vassilios; Ghiran, Ionita; Shah, Ravi; Li, Yongqin; Zhang, Yuhui; Das, Saumya; Xiao, Junjie

2017-07-01

Extracellular vesicles (EVs) serve an important function as mediators of intercellular communication. Exercise is protective for the heart, although the signaling mechanisms that mediate this cardioprotection have not been fully elucidated. Here using nano-flow cytometry, we found a rapid increase in plasma EVs in human subjects undergoing exercise stress testing. We subsequently identified that serum EVs were increased by ~1.85-fold in mice after 3-week swimming. Intramyocardial injection of equivalent quantities of EVs from exercised mice and non-exercised controls provided similar protective effects against acute ischemia/reperfusion (I/R) injury in mice. However, injection of exercise-induced EVs in a quantity equivalent to the increase seen with exercise (1.85 swim group) significantly enhanced the protective effect. Similarly, treatment with exercise-induced increased EVs provided additional anti-apoptotic effect in H 2 O 2 -treated H9C2 cardiomyocytes mediated by the activation of ERK1/2 and HSP27 signaling. Finally, by treating H9C2 cells with insulin-like growth factor-1 to mimic exercise stimulus in vitro, we found an increased release of EVs from cardiomyocytes associated with ALIX and RAB35 activation. Collectively, our results show that exercise-induced increase in circulating EVs enhances the protective effects of endogenous EVs against cardiac I/R injury. Exercise-derived EVs might serve as a potent therapy for myocardial injury in the future.
Ocular vestibular evoked myogenic potential in patients with benign paroxysmal positional vertigo

Directory of Open Access Journals (Sweden)

Mozhgan Masoom

2014-06-01

Full Text Available Background and Aim: Since utricle is the main damaged organ in benign paroxysmal positional vertigo (BPPV, ocular vestibular evoked myogenic potential (oVEMP may be an appropriate method to evaluate the utricule dysfunction and the effect of disease recurrence rate on it. This study aimed to record myogenic potential in patients with benign paroxysmal positional vertigo.Methods: In a cross-sectional study, ocular myogenic potential was recorded in 25 healthy subjects and 20 patients with benign paroxysmal positional vertigo using 500 Hz-tone bursts (95 dB nHL.Results: In the affected ear, mean amplitude was lower and mean threshold was higher than those in the unaffected ear and in the normal group (p<0.05. Mean amplitude asymmetry ratio of patients was more than the healthy subjects (p0.05. Frequencies of abnormal responses in the affected ears were higher than in unaffected ears and in the normal group (p<0.05. Furthermore, the patients with recurrent vertigo showed more abnormalities than the patients with non-recurrent (p=0.030.Conclusion: In the recurrent benign paroxysmal positional vertigo, ocular vestibular evoked myogenic potential showed more damage in the utricle, suggesting this response could be used to evaluate the patients with benign paroxysmal positional vertigo.
Selection of reference genes for expression studies with fish myogenic cell cultures

Directory of Open Access Journals (Sweden)

Johnston Ian A

2009-08-01

Full Text Available Abstract Background Relatively few studies have used cell culture systems to investigate gene expression and the regulation of myogenesis in fish. To produce robust data from quantitative real-time PCR mRNA levels need to be normalised using internal reference genes which have stable expression across all experimental samples. We have investigated the expression of eight candidate genes to identify suitable reference genes for use in primary myogenic cell cultures from Atlantic salmon (Salmo salar L.. The software analysis packages geNorm, Normfinder and Best keeper were used to rank genes according to their stability across 42 samples during the course of myogenic differentiation. Results Initial results showed several of the candidate genes exhibited stable expression throughout myogenic culture while Sdha was identified as the least stable gene. Further analysis with geNorm, Normfinder and Bestkeeper identified Ef1α, Hprt1, Ppia and RNApolII as stably expressed. Comparison of data normalised with the geometric average obtained from combinations of any three of these genes showed no significant differences, indicating that any combination of these genes is valid. Conclusion The geometric average of any three of Hprt1, Ef1α, Ppia and RNApolII is suitable for normalisation of gene expression data in primary myogenic cultures from Atlantic salmon.
Selection of reference genes for expression studies with fish myogenic cell cultures.

Science.gov (United States)

Bower, Neil I; Johnston, Ian A

2009-08-10

Relatively few studies have used cell culture systems to investigate gene expression and the regulation of myogenesis in fish. To produce robust data from quantitative real-time PCR mRNA levels need to be normalised using internal reference genes which have stable expression across all experimental samples. We have investigated the expression of eight candidate genes to identify suitable reference genes for use in primary myogenic cell cultures from Atlantic salmon (Salmo salar L.). The software analysis packages geNorm, Normfinder and Best keeper were used to rank genes according to their stability across 42 samples during the course of myogenic differentiation. Initial results showed several of the candidate genes exhibited stable expression throughout myogenic culture while Sdha was identified as the least stable gene. Further analysis with geNorm, Normfinder and Bestkeeper identified Ef1alpha, Hprt1, Ppia and RNApolII as stably expressed. Comparison of data normalised with the geometric average obtained from combinations of any three of these genes showed no significant differences, indicating that any combination of these genes is valid. The geometric average of any three of Hprt1, Ef1alpha, Ppia and RNApolII is suitable for normalisation of gene expression data in primary myogenic cultures from Atlantic salmon.
Myogenesis in the sea urchin embryo: the molecular fingerprint of the myoblast precursors

Science.gov (United States)

2013-01-01

Background In sea urchin larvae the circumesophageal fibers form a prominent muscle system of mesodermal origin. Although the morphology and later development of this muscle system has been well-described, little is known about the molecular signature of these cells or their precise origin in the early embryo. As an invertebrate deuterostome that is more closely related to the vertebrates than other commonly used model systems in myogenesis, the sea urchin fills an important phylogenetic gap and provides a unique perspective on the evolution of muscle cell development. Results Here, we present a comprehensive description of the development of the sea urchin larval circumesophageal muscle lineage beginning with its mesodermal origin using high-resolution localization of the expression of several myogenic transcriptional regulators and differentiation genes. A few myoblasts are bilaterally distributed at the oral vegetal side of the tip of the archenteron and first appear at the late gastrula stage. The expression of the differentiation genes Myosin Heavy Chain, Tropomyosin I and II, as well as the regulatory genes MyoD2, FoxF, FoxC, FoxL1, Myocardin, Twist, and Tbx6 uniquely identify these cells. Interestingly, evolutionarily conserved myogenic factors such as Mef2, MyoR and Six1/2 are not expressed in sea urchin myoblasts but are found in other mesodermal domains of the tip of the archenteron. The regulatory states of these domains were characterized in detail. Moreover, using a combinatorial analysis of gene expression we followed the development of the FoxF/FoxC positive cells from the onset of expression to the end of gastrulation. Our data allowed us to build a complete map of the Non-Skeletogenic Mesoderm at the very early gastrula stage, in which specific molecular signatures identify the precursors of different cell types. Among them, a small group of cells within the FoxY domain, which also express FoxC and SoxE, have been identified as plausible myoblast
Systemic Exercise-Induced Hypoalgesia Following Isometric Exercise Reduces Conditioned Pain Modulation.

Science.gov (United States)

Alsouhibani, Ali; Vaegter, Henrik Bjarke; Hoeger Bement, Marie

2018-04-03

Physically active individuals show greater conditioned pain modulation (CPM) compared with less active individuals. Understanding the effects of acute exercise on CPM may allow for a more targeted use of exercise in the management of pain. This study investigated the effects of acute isometric exercise on CPM. In addition, the between-session and within-session reliability of CPM was investigated. Experimental, randomized crossover study. Laboratory at Marquette University. Thirty healthy adults (19.3±1.5 years, 15 males). Subjects underwent CPM testing before and after isometric exercise (knee extension, 30% maximum voluntary contraction for three minutes) and quiet rest in two separate experimental sessions. Pressure pain thresholds (PPTs) at the quadriceps and upper trapezius muscles were assessed before, during, and after ice water immersions. PPTs increased during ice water immersion (i.e., CPM), and quadriceps PPT increased after exercise (P CPM decreased similarly following exercise and quiet rest (P > 0.05). CPM within-session reliability was fair to good (intraclass correlation coefficient [ICC] = 0.43-0.70), and the between-session reliability was poor (ICC = 0.20-0.35). Due to the variability in the systemic exercise-induced hypoalgesia (EIH) response, participants were divided into systemic EIH responders (N = 9) and nonresponders (N = 21). EIH responders experienced attenuated CPM following exercise (P = 0.03), whereas the nonresponders showed no significant change (P > 0.05). Isometric exercise decreased CPM in individuals who reported systemic EIH, suggesting activation of shared mechanisms between CPM and systemic EIH responses. These results may improve the understanding of increased pain after exercise in patients with chronic pain and potentially attenuated CPM.
Astragalus membranaceus Improves Exercise Performance and Ameliorates Exercise-Induced Fatigue in Trained Mice

Directory of Open Access Journals (Sweden)

Tzu-Shao Yeh

2014-03-01

Full Text Available Astragalus membranaceus (AM is a popular “Qi-tonifying” herb with a long history of use as a Traditional Chinese Medicine with multiple biological functions. However, evidence for the effects of AM on exercise performance and physical fatigue is limited. We evaluated the potential beneficial effects of AM on ergogenic and anti-fatigue functions following physiological challenge. Male ICR strain mice were randomly assigned to four groups (n = 10 per group for treatment: (1 sedentary control and vehicle treatment (vehicle control; (2 exercise training with vehicle treatment (exercise control; and (3 exercise training with AM treatment at 0.615 g/kg/day (Ex-AM1 or (4 3.075 g/kg/day (Ex-AM5. Both the vehicle and AM were orally administered for 6 weeks. Exercise performance and anti-fatigue function were evaluated by forelimb grip strength, exhaustive swimming time, and levels of serum lactate, ammonia, glucose, and creatine kinase after 15-min swimming exercise. Exercise training combined with AM supplementation increased endurance exercise capacity and increased hepatic and muscle glycogen content. AM reduced exercise-induced accumulation of the byproducts blood lactate and ammonia with acute exercise challenge. Moreover, we found no deleterious effects from AM treatment. Therefore, AM supplementation improved exercise performance and had anti-fatigue effects in mice. It may be an effective ergogenic aid in exercise training.
Characteristics of myogenic response and ankle torque recovery after lengthening contraction-induced rat gastrocnemius injury

Directory of Open Access Journals (Sweden)

Song Hongsun

2012-10-01

Full Text Available Abstract Background Although muscle dysfunction caused by unfamiliar lengthening contraction is one of most important issues in sports medicine, there is little known about the molecular events on regeneration process. The purpose of this study was to investigate the temporal and spatial expression patterns of myogenin, myoD, pax7, and myostatin after acute lengthening contraction (LC-induced injury in the rat hindlimb. Methods We employed our originally developed device with LC in rat gastrocnemius muscle (n = 24. Male Wistar rats were anesthetized with isoflurane (aspiration rate, 450 ml/min, concentration, 2.0%. The triceps surae muscle of the right hindlimb was then electrically stimulated with forced isokinetic dorsi-flexion (180°/sec and from 0 to 45°. Tissue contents of myoD, myogenin, pax7, myostatin were measured by western blotting and localizations of myoD and pax7 was measured by immunohistochemistry. After measuring isometric tetanic torque, a single bout of LC was performed in vivo. Results The torque was significantly decreased on days 2 and 5 as compared to the pre-treatment value, and recovered by day 7. The content of myoD and pax7 showed significant increases on day 2. Myogenin showed an increase from day 2 to 5. Myostatin on days 5 and 7 were significantly increased. Immunohistochemical analysis showed that myoD-positive/pax7-positive cells increased on day 2, suggesting that activated satellite cells play a role in the destruction and the early recovery phases. Conclusion We, thus, conclude that myogenic events associate with torque recovery after LC-induced injury.
Myogenic potential of canine craniofacial satellite cells

Directory of Open Access Journals (Sweden)

Rita Maria Laura La Rovere

2014-05-01

Full Text Available The skeletal fibres have different embryological origin; the extraocular and jaw-closer muscles develop from prechordal mesoderm while the limb and trunk muscles from somites. These different origins characterise also the adult muscle stem cells, known as satellite cells (SCs and responsible for the fibre growth and regeneration. The physiological properties of presomitic SCs and their epigenetics are poorly studied despite their peculiar characteristics to preserve muscle integrity during chronic muscle degeneration. Here we isolated SCs from canine somitic (SDM: vastus lateralis, rectus abdominus, gluteus superficialis, biceps femoris, psoas and presomitic (PSDM: lateral rectus, temporalis and retractor bulbi muscles as myogenic progenitor cells from young and old animals. In addition, SDM and PSDM satellite cells were obtained also from Golden retrievers affected by muscular dystrophy (GRMD. We characterised the lifespan, the myogenic potential and functions and oxidative stress of both somitic and presomitic SCs with the aim to reveal differences with ageing and between healthy and dystrophic animals. The different proliferation rate was consistent with higher telomerase activity in PSDM-SCs compared to SDM-SCs, although restricted at early passages. SDM-SCs express early (Pax7, MyoD and late (MyHC, Myogenin myogenic markers differently from PSDM-SCs resulting in a more efficient and faster cell differentiation. Taken together our results showed that PSDM-SCs elicit a stronger stem cell phenotype compared to SDM ones. Finally, myomiR expression profile reveals a unique epigenetic signature in GRMD satellite cells and miR-206, highly expressed in dystrophic SCs, seems to play a critical role in muscle degeneration. Thus, miR-206 could represent a potential target for novel therapeutic approaches.
IL-6 Impairs Myogenic Differentiation by Downmodulation of p90RSK/eEF2 and mTOR/p70S6K Axes, without Affecting AKT Activity

Directory of Open Access Journals (Sweden)

Michele Pelosi

2014-01-01

Full Text Available IL-6 is a multifaceted pleiotropic cytokine, which is produced by a variety of cell types and targets different cells and tissues. In physiological conditions, IL-6 can be locally and transiently produced by skeletal muscle and plays an important role in muscle homeostasis. Circulating IL-6 levels are normally very low or undetectable but are dramatically increased in several pathologic conditions. In this study, we aimed to define the potential molecular mechanisms underlying the effects of IL-6 on myogenic program. We explored the molecular mechanisms through which exogenous IL-6, or the conditioned medium from the murine C-26 adenocarcinoma cells (a cellular model that secretes high levels of IL-6 and induces cancer cachexia in mice, interferes with the myogenic program. Our study revealed that IL-6 induces the activation of the Stat3 signaling and promotes the downmodulation of the p90RSK/eEF2 and mTOR/p70S6K axes, while it does not affect the activation of AKT. We thus identified potential molecular mediators of the inhibitory effects of IL-6 on myogenic program.
Sphingosine-1-Phosphate Signaling Regulates Myogenic Responsiveness in Human Resistance Arteries.

Directory of Open Access Journals (Sweden)

Sonya Hui

Full Text Available We recently identified sphingosine-1-phosphate (S1P signaling and the cystic fibrosis transmembrane conductance regulator (CFTR as prominent regulators of myogenic responsiveness in rodent resistance arteries. However, since rodent models frequently exhibit limitations with respect to human applicability, translation is necessary to validate the relevance of this signaling network for clinical application. We therefore investigated the significance of these regulatory elements in human mesenteric and skeletal muscle resistance arteries. Mesenteric and skeletal muscle resistance arteries were isolated from patient tissue specimens collected during colonic or cardiac bypass surgery. Pressure myography assessments confirmed endothelial integrity, as well as stable phenylephrine and myogenic responses. Both human mesenteric and skeletal muscle resistance arteries (i express critical S1P signaling elements, (ii constrict in response to S1P and (iii lose myogenic responsiveness following S1P receptor antagonism (JTE013. However, while human mesenteric arteries express CFTR, human skeletal muscle resistance arteries do not express detectable levels of CFTR protein. Consequently, modulating CFTR activity enhances myogenic responsiveness only in human mesenteric resistance arteries. We conclude that human mesenteric and skeletal muscle resistance arteries are a reliable and consistent model for translational studies. We demonstrate that the core elements of an S1P-dependent signaling network translate to human mesenteric resistance arteries. Clear species and vascular bed variations are evident, reinforcing the critical need for further translational study.
Increased arterial smooth muscle Ca2+ signaling, vasoconstriction, and myogenic reactivity in Milan hypertensive rats

Science.gov (United States)

Linde, Cristina I.; Karashima, Eiji; Raina, Hema; Zulian, Alessandra; Wier, Withrow G.; Hamlyn, John M.; Ferrari, Patrizia; Blaustein, Mordecai P.

2012-01-01

The Milan hypertensive strain (MHS) rats are a genetic model of hypertension with adducin gene polymorphisms linked to enhanced renal tubular Na+ reabsorption. Recently we demonstrated that Ca2+ signaling is augmented in freshly isolated mesenteric artery myocytes from MHS rats. This is associated with greatly enhanced expression of Na+/Ca2+ exchanger-1 (NCX1), C-type transient receptor potential (TRPC6) protein, and sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2) compared with arteries from Milan normotensive strain (MNS) rats. Here, we test the hypothesis that the enhanced Ca2+ signaling in MHS arterial smooth muscle is directly reflected in augmented vasoconstriction [myogenic and phenylephrine (PE)-evoked responses] in isolated mesenteric small arteries. Systolic blood pressure was higher in MHS (145 ± 1 mmHg) than in MNS (112 ± 1 mmHg; P arteries from MHS rats had significantly augmented myogenic tone and reactivity and enhanced constriction to low-dose (1–100 nM) PE. Isolated MHS arterial myocytes exhibited approximately twofold increased peak Ca2+ signals in response to 5 μM PE or ATP in the absence and presence of extracellular Ca2+. These augmented responses are consistent with increased vasoconstrictor-evoked sarcoplasmic reticulum (SR) Ca2+ release and increased Ca2+ entry, respectively. The increased SR Ca2+ release correlates with a doubling of inositol 1,4,5-trisphosphate receptor type 1 and tripling of SERCA2 expression. Pressurized MHS arteries also exhibited a ∼70% increase in 100 nM ouabain-induced vasoconstriction compared with MNS arteries. These functional alterations reveal that, in a genetic model of hypertension linked to renal dysfunction, multiple mechanisms within the arterial myocytes contribute to enhanced Ca2+ signaling and myogenic and vasoconstrictor-induced arterial constriction. MHS rats have elevated plasma levels of endogenous ouabain, which may initiate the protein upregulation and enhanced Ca2+ signaling. These
Exercise-Induced Pulmonary Edema in a Triathlon

Directory of Open Access Journals (Sweden)

Hirotomo Yamanashi

2015-01-01

Full Text Available Introduction. Family physicians have more opportunities to attend athletic competitions as medical staff at first-aid centers because of the increasing popularity of endurance sports. Case. A 38-year-old man who participated in a triathlon race experienced difficulty in breathing after swimming and was moved to a first-aid center. His initial oxygen saturation was 82% and a thoracic computed tomography scan showed bilateral ground glass opacity in the peripheral lungs. His diagnosis was noncardiogenic pulmonary edema associated with exercise or swimming: exercise-induced pulmonary edema (EIPE or swimming-induced pulmonary edema (SIPE. Treatment with furosemide and corticosteroid relieved his symptoms of pulmonary edema. Discussion. Noncardiogenic pulmonary edema associated with endurance sports is not common, but knowledge about EIPE/SIPE or neurogenic pulmonary edema associated with hyponatremia, which is called Ayus-Arieff syndrome, is crucial. Knowledge and caution for possible risk factors, such as exposure to cold water or overhydration, are essential for both medical staff and endurance athletes. Conclusion. To determine the presence of pulmonary edema associated with strenuous exercise, oxygen saturation should be used as a screening tool at a first-aid center. To avoid risks for EIPE/SIPE, knowledge about these diseases is essential for medical staff and for athletes who perform extreme exercise.
PAX7 Targets, CD54, Integrin α9β1, and SDC2, Allow Isolation of Human ESC/iPSC-Derived Myogenic Progenitors

Directory of Open Access Journals (Sweden)

Alessandro Magli

2017-06-01

Full Text Available Pluripotent stem (PS-cell-derived cell types hold promise for treating degenerative diseases. However, PS cell differentiation is intrinsically heterogeneous; therefore, clinical translation requires the development of practical methods for isolating progenitors from unwanted and potentially teratogenic cells. Muscle-regenerating progenitors can be derived through transient PAX7 expression. To better understand the biology, and to discover potential markers for these cells, here we investigate PAX7 genomic targets and transcriptional changes in human cells undergoing PAX7-mediated myogenic commitment. We identify CD54, integrin α9β1, and Syndecan2 (SDC2 as surface markers on PAX7-induced myogenic progenitors. We show that these markers allow for the isolation of myogenic progenitors using both fluorescent- and CGMP-compatible magnetic-based sorting technologies and that CD54+α9β1+SDC2+ cells contribute to long-term muscle regeneration in vivo. These findings represent a critical step toward enabling the translation of PS-cell-based therapies for muscle diseases.
Effects of Uric Acid on Exercise-induced Oxidative Stress

OpenAIRE

平井, 富弘

2001-01-01

We studied effects of uric acid on exercise― induced oxidative stress in humans based on a hypothesis that uric acid acts as an antioxidant to prevent from exercise―induced oxidative stress. Relation between uric acid level in plasma and increase of thiobarbituric acid reactive substance (TBARS)after the cycle ergometer exercise was examined. Thiobarbituricacid reactive substance in plasma increased after the ergometer exercise. High uric acid in plasma did not result in low increase of TBARS...
Mechanisms and management of exercise-induced asthma in elite athletes

DEFF Research Database (Denmark)

Ali, Zarqa; Norsk, Peter; Ulrik, Charlotte Suppli

2012-01-01

Asthma is often reported by elite athletes, especially endurance athletes. The aim of this article is to review current knowledge of mechanisms and management of exercise-induced asthma (EIA) in adult elite athletes.......Asthma is often reported by elite athletes, especially endurance athletes. The aim of this article is to review current knowledge of mechanisms and management of exercise-induced asthma (EIA) in adult elite athletes....
Interaural difference values of vestibular evoked myogenic.

Directory of Open Access Journals (Sweden)

Marziyeh Moallemi

2015-01-01

Full Text Available Migraine is a neurologic disease, which often is associated with a unilateral headache. Vestibular abnormalities are common in migraine. Vestibular evoked myogenic potentials (VEMPs assess otolith function in particular functional integrity of the saccule and the inferior vestibular nerve. We used VEMP to evaluate if the migraine headache can affect VEMP asymmetry parameters. A total of 25 patients with migraine (22 females and 3 males who were diagnosed according to the criteria of IHS-1988 were enrolled in this cross-sectional study. Control group consisted of 26 healthy participants (18 female and 8 male, without neurotological symptoms and history of migraine. The short tone burst (95 dB nHL, 500 Hz was presented to ears. VEMP was recorded with surface electromyography over the contracted ipsilateral sternocleidomastoid (SCM muscle. Although current results showed that the amplitude ratio is greater in migraine patients than normal group, there was no statistical difference between two groups in mean asymmetry parameters of VEMP. Asymmetry measurements in vestibular evoked myogenic potentials probably are not indicators of unilateral deficient in saccular pathways of migraine patients.

The Curious Question of Exercise-Induced Pulmonary Edema

Directory of Open Access Journals (Sweden)

Melissa L. Bates

2011-01-01

Full Text Available The question of whether pulmonary edema develops during exercise on land is controversial. Yet, the development of pulmonary edema during swimming and diving is well established. This paper addresses the current controversies that exist in the field of exercise-induced pulmonary edema on land and with water immersion. It also discusses the mechanisms by which pulmonary edema can develop during land exercise, swimming, and diving and the current gaps in knowledge that exist. Finally, this paper discusses how these fields can continue to advance and the areas where clinical knowledge is lacking.
Neonatal epicardial-derived progenitors aquire myogenic traits in skeletal muscle, but not cardiac muscle

DEFF Research Database (Denmark)

Andersen, Ditte C; Jensen, Charlotte H; Skovrind, Ida

2016-01-01

heart missing regenerative signals essential for directed differentiation of EPDCs. Herein, we aimed to evaluate the myogenic potential of neonatal EPDCs in adult and neonatal mouse myocardium, as well as in skeletal muscle. The two latter tissues have an intrinsic capability to develop and regenerate......, in contrast to the adult heart. METHODS: Highly purified mouse EPDCs were transplanted into damaged neonatal and adult myocardium as well as regenerating skeletal muscle. Co-cultures with skeletal myoblasts were used to distinguish fusion independent myogenic conversion. RESULTS: No donor EPDC...... that EPDCs may be more myogenic than previously anticipated. But, the heart may lack factors for induction of myogenesis of EPDCs, a scenario that should be taken into consideration when aiming for repair of damaged myocardium by stem cell transplantation....
Exercise-induced heat stress disrupts the shear-dilatory relationship.

Science.gov (United States)

Ives, Stephen J; Lefferts, Wesley K; Wharton, Margret; Fehling, Patricia C; Smith, Denise L

2016-12-01

What is the central question of this study? Although heat stress is known to increase cardiovascular strain, no study, to date, had explored the potential impact of exercise-induced heat stress on vascular function. What is the main finding and its importance? We found that acute exercise tended to reduce flow-mediated dilatation (FMD), owing in part to reduced reactive hyperaemia/shear stimulus; thus, when FMD is normalized to shear no postexercise deficit exists. Exercise-induced heat stress increased reactive hyperaemia, shear rate, coupled with a sustained FMD postexercise, suggests that exercise-induced heat stress increases the amount of shear stimulus to elicit a similar response, indicating reduced vascular responsiveness, or reserve, which might increase cardiovascular susceptibility. Heat stress increases cardiovascular strain and is of particular concern in occupations, such as firefighting, in which individuals are required to perform strenuous work while wearing personal protective equipment. Sudden cardiac events are associated with strenuous activity and are the leading cause of duty-related death among firefighters, accounting for ∼50% of duty-related fatalities per year. Understanding the acute effects of exercise-induced heat stress (EIHS) on vascular endothelial function may provide insight into the mechanisms precipitating acute coronary events in firefighters. The purpose of this study, therefore, was to determine the effects of EIHS on vascular endothelial function. Using a balanced crossover design, 12 healthy men performed 100 min of moderate-intensity, intermittent exercise with and without EIHS (personal protective equipment or cooling vest, respectively). Measurements of flow-mediated dilatation (FMD), reactive hyperaemia and shear rate area under the curve (SR AUC ) were performed pre- and postexercise. During EIHS, core temperature was significantly higher (38 ± 0.1 versus 37 ± 0.1°C). Postexercise FMD tended to be suppressed
Global Proteome Changes in the Rat Diaphragm Induced by Endurance Exercise Training.

Directory of Open Access Journals (Sweden)

Kurt J Sollanek

Full Text Available Mechanical ventilation (MV is a life-saving intervention for many critically ill patients. Unfortunately, prolonged MV results in the rapid development of diaphragmatic atrophy and weakness. Importantly, endurance exercise training results in a diaphragmatic phenotype that is protected against ventilator-induced diaphragmatic atrophy and weakness. The mechanisms responsible for this exercise-induced protection against ventilator-induced diaphragmatic atrophy remain unknown. Therefore, to investigate exercise-induced changes in diaphragm muscle proteins, we compared the diaphragmatic proteome from sedentary and exercise-trained rats. Specifically, using label-free liquid chromatography-mass spectrometry, we performed a proteomics analysis of both soluble proteins and mitochondrial proteins isolated from diaphragm muscle. The total number of diaphragm proteins profiled in the soluble protein fraction and mitochondrial protein fraction were 813 and 732, respectively. Endurance exercise training significantly (P<0.05, FDR <10% altered the abundance of 70 proteins in the soluble diaphragm proteome and 25 proteins of the mitochondrial proteome. In particular, key cytoprotective proteins that increased in relative abundance following exercise training included mitochondrial fission process 1 (Mtfp1; MTP18, 3-mercaptopyruvate sulfurtransferase (3MPST, microsomal glutathione S-transferase 3 (Mgst3; GST-III, and heat shock protein 70 kDa protein 1A/1B (HSP70. While these proteins are known to be cytoprotective in several cell types, the cyto-protective roles of these proteins have yet to be fully elucidated in diaphragm muscle fibers. Based upon these important findings, future experiments can now determine which of these diaphragmatic proteins are sufficient and/or required to promote exercise-induced protection against inactivity-induced muscle atrophy.
N-Acetylcysteine treatment of dystrophic mdx mice results in protein thiol modifications and inhibition of exercise induced myofibre necrosis.

Science.gov (United States)

Terrill, Jessica R; Radley-Crabb, Hannah G; Grounds, Miranda D; Arthur, Peter G

2012-05-01

Oxidative stress is implicated as a factor that increases necrosis of skeletal muscles in Duchenne Muscular Dystrophy (DMD) and the dystrophic mdx mouse. Consequently, drugs that minimize oxidative stress are potential treatments for muscular dystrophy. This study examined the in vivo benefits to mdx mice of an antioxidant treatment with the cysteine precursor N-acetylcysteine (NAC), administered in drinking water. NAC was completely effective in preventing treadmill exercise-induced myofibre necrosis (assessed histologically) and the increased blood creatine kinase levels (a measure of sarcolemma leakiness) following exercise were significantly lower in the NAC treated mice. While NAC had no effect on malondialdehyde level or protein carbonylation (two indicators of irreversible oxidative damage), treatment with NAC for one week significantly decreased the oxidation of glutathione and protein thiols, and enhanced muscle protein thiol content. These data provide in vivo evidence for protective benefits of NAC treatment on dystropathology, potentially via protein thiol modifications. Copyright © 2011 Elsevier B.V. All rights reserved.
ALDH2 restores exhaustive exercise-induced mitochondrial dysfunction in skeletal muscle

International Nuclear Information System (INIS)

Zhang, Qiuping; Zheng, Jianheng; Qiu, Jun; Wu, Xiahong; Xu, Yangshuo; Shen, Weili; Sun, Mengwei

2017-01-01

Background: Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is highly expressed in heart and skeletal muscles, and is the major enzyme that metabolizes acetaldehyde and toxic aldehydes. The cardioprotective effects of ALDH2 during cardiac ischemia/reperfusion injury have been recognized. However, less is known about the function of ALDH2 in skeletal muscle. This study was designed to evaluate the effect of ALDH2 on exhaustive exercise-induced skeletal muscle injury. Methods: We created transgenic mice expressing ALDH2 in skeletal muscles. Male wild-type C57/BL6 (WT) and ALDH2 transgenic mice (ALDH2-Tg), 8-weeks old, were challenged with exhaustive exercise for 1 week to induce skeletal muscle injury. Animals were sacrificed 24 h post-exercise and muscle tissue was excised. Results: ALDH2-Tg mice displayed significantly increased treadmill exercise capacity compared to WT mice. Exhaustive exercise caused an increase in mRNA levels of the muscle atrophy markers, Atrogin-1 and MuRF1, and reduced mitochondrial biogenesis and fusion in WT skeletal muscles; these effects were attenuated in ALDH2-Tg mice. Exhaustive exercise also enhanced mitochondrial autophagy pathway activity, including increased conversion of LC3-I to LC3-II and greater expression of Beclin1 and Bnip3; the effects of which were mitigated by ALDH2 overexpression. In addition, ALDH2-Tg reversed the increase of an oxidative stress biomarker (4-hydroxynonenal) and decreased levels of mitochondrial antioxidant proteins, including manganese superoxide dismutase and NAD(P)H:quinone oxidoreductase 1, in skeletal muscle induced by exhaustive exercise. Conclusion: ALDH2 may reverse skeletal muscle mitochondrial dysfunction due to exhaustive exercise by regulating mitochondria dynamic remodeling and enhancing the quality of mitochondria. - Highlights: • Skeletal muscle ALDH2 expression and activity declines during exhaustive exercise. • ALDH2 overexpression enhances physical performance and restores muscle
Fatty acid-inducible ANGPTL4 governs lipid metabolic response to exercise

DEFF Research Database (Denmark)

Catoire, Milène; Alex, Sheril; Paraskevopulos, Nicolas

2014-01-01

Physical activity increases energy metabolism in exercising muscle. Whether acute exercise elicits metabolic changes in nonexercising muscles remains unclear. We show that one of the few genes that is more highly induced in nonexercising muscle than in exercising human muscle during acute exercis...
The effectiveness of the treatment of severe exercise-induced asthma in schoolchildren

Directory of Open Access Journals (Sweden)

M.N. Garas

2017-03-01

Full Text Available Background. Bronchial asthma is one of the most common chronic multifactorial diseases of the lungs. At least 10–12 % of patients with bronchial asthma are suffering from a severe form of the disease. One aspect of inadequate severe asthma control is its phenotypic heterogeneity, interest of experts increases to the problem of exercise-induced asthma. The purpose of the study was to increase efficiency of treatment for severe exercise-induced asthma in schoolchildren based on the analysis of the attack dynamics and to achieve disease control according to main inflammatometric and spirometric indices. Materials and methods. We examined 46 children with severe persistent bronchial asthma, in particular, 15 schoolchildren suffering from severe exercise-induced asthma, the second clinical group (comparison one consisted of 31 children suffering from severe type of the disease, with no signs of exercise-induced bronchoconstriction. Basic therapy effectiveness was determined prospectively by assessing the disease control using AST-test with an interval of 3 months. The severity of bronchial obstruction syndrome in patients on admission to hospital during exacerbation was assessed by score scale. Airway hyperresponsiveness was evaluated according to the results of bronchoprovocation with histamine. Results. Children of I clinical group had more significant manifestations of bronchial obstruction during the week of inpatient treatment than the comparison group of patients, including significantly more severe manifestations of bronchial obstruction were verified on 1st and 7th day of hospitalization. Due to the analysis of basic therapy effectiveness, only a quarter of I clinical group patients and a larger part of schoolchildren in comparison group achieved the partial control after a 3-month course of anti-inflammatory treatment. Eosinophilic inflammation was observed in most children with severe exercise-induced asthma (60.1 % and in 47.2 % of
Exercise Does Not Protect against MPTP-Induced Neurotoxicity in BDNF Happloinsufficent Mice

OpenAIRE

Gerecke, Kim M.; Jiao, Yun; Pagala, Viswajeeth; Smeyne, Richard J.

2012-01-01

Exercise has been demonstrated to potently protect substantia nigra pars compacta (SN) dopaminergic neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity. One mechanism proposed to account for this neuroprotection is the upregulation of neurotrophic factors. Several neurotrophic factors, including Brain Derived Neurotrophic Factor (BDNF), have been shown to upregulate in response to exercise. In order to determine if exercise-induced neuroprotection is depende...
Exercise-induced asthma: critical analysis of the protective role of montelukast

Directory of Open Access Journals (Sweden)

Terrence W Carver Jr

2009-10-01

Full Text Available Terrence W Carver JrThe Children’s Mercy Hospital and Clinics, Kansas City, MO, USAAbstract: Exercise-induced asthma/exercise-induced bronchospasm (EIA/EIB is a prevalent and clinically important disease affecting young children through older adulthood. These terms are often used interchangeably and the differences are not clearly defined in the literature. The pathogenesis of EIA/EIB may be different in those with persistent asthma compared to those with exercise-induced symptoms only. The natural history of EIA is unclear and may be different for elite athletes. Leukotriene biology has helped the understanding of EIB. The type and intensity of exercise are important factors for EIB. Exercise participation is necessary for proper development and control of EIA is recommended. Symptoms of EIB should be confirmed by proper testing. Biologic markers may also be helpful in diagnosis. Not all exercise symptoms are from EIB. Many medication and nonpharmacologic treatments are available. Asthma education is an important component of managing EIA. Many medications have been tested and the comparisons are complicated. Montelukast is a US Food and Drug Administration-approved asthma and EIB controller and has a number of potential advantages to other asthma medications including short onset of action, ease of use, and lack of tolerance. Not all patients improve with montelukast and rescue medication should be available.Keywords: exercise, asthma, montelukast, Singulair, bronchospasm, leukotrienes
FoxO6 and PGC-1? form a regulatory loop in myogenic cells

OpenAIRE

Chung, Shih?Ying; Huang, Wei?Chieh; Su, Ching?Wen; Lee, Kuan?Wei; Chi, Hsiang?Cheng; Lin, Cheng?Tao; Chen, Szu-Tah; Huang, Kai?Min; Tsai, Mu?Shiun; Yu, Hui?Peng; Chen, Shen?Liang

2013-01-01

Transcription factors of the FoxO (forkhead box O) family regulate a wide range of cellular physiological processes, including metabolic adaptation and myogenic differentiation. The transcriptional activity of most FoxO members is inhibitory to myogenic differentiation and overexpression of FoxO1 inhibits the development of oxidative type?I fibres in?vivo. In this study, we found that FoxO6, the last discovered FoxO family member, is expressed ubiquitously in various tissues but with higher e...
Comparison of Vestibular Evoked Myogenic Potential and Caloric Tests Findings in Noise Induced Hearing Loss-Affected and Healthy Individuals

Directory of Open Access Journals (Sweden)

Farinoosh Fakharnia

2010-06-01

Full Text Available Background and Aim: Balance disturbance is one of the non-auditory effects of noisy industrial environments that is usually neglected. The aim of the current study was to investigate the effect of occupational noise on vestibular system among workers with noise-induced hearing loss (NIHL, based on both vestibular evoked myogenic potentials (VEMP and caloric tests.Methods: Thirty male workers with noise-induced hearing loss and thirty male matched controls were examined by VEMP and caloric tests. Study parameters included unilateral weakness, p13 and n23 latencies, and p13-n23 amplitude. Caloric test was performed only for 20 patients.Results: No significant difference was observed in unilateral weakness between the two groups. On the other hand, the difference in mean latencies of p13 in the right ear (p=0.003 and left ear (p=0.01 was significant between the two groups. However, the difference in n23 latency was significant only in the right ear (p=0.03. There was no significant difference between groups in p13-n23 amplitude.Conclusion: It seems that pars inferior of vestibule is the susceptible part in individuals with NIHL. In general, abnormal findings in both VEMP and caloric tests were more common compared to functional symptoms such as vertigo, which may be due to central compensation and the symmetry of the disorder.
Altered myogenic vasoconstriction and regulation of whole kidney blood flow in the ASIC2 knockout mouse.

Science.gov (United States)

Gannon, Kimberly P; McKey, Susan E; Stec, David E; Drummond, Heather A

2015-02-15

Previous studies from our laboratory have suggested that degenerin proteins contribute to myogenic constriction, a mechanism of blood flow regulation and protection against pressure-dependent organ injury, in renal vessels. The goal of the present study was to determine the importance of one family member, acid-sensing ion channel 2 (ASIC2), in myogenic constriction of renal interlobar arteries, myogenic regulation of whole kidney blood flow, renal injury, and blood pressure using ASIC2(+/+), ASIC2(+/-), and ASIC2(-/-) mice. Myogenic constriction in renal interlobar arteries was impaired in ASIC2(+/-) and ASIC2(-/-) mice, whereas constriction to KCl/phenylephrine was unchanged. Correction of whole kidney renal vascular resistance (RVR) during the first 5 s after a 10- to 20-mmHg step increase in perfusion pressure, a timeframe associated with myogenic-mediated correction of RVR, was slowed (4.2 ± 0.9, 0.3 ± 0.7, and 2.4 ± 0.3 resistance units/s in ASIC2(+/+), ASIC2(+/-), and ASIC2(-/-) mice). Although modest reductions in function were observed in ASIC2(-/-) mice, greater reductions were observed in ASIC2(+/-) mice, which may be explained by protein-protein interactions of ASIC2 with other degenerins. Isolated glomeruli from ASIC2(+/-) and ASIC2(-/-) mice had modest alterations in the expression of inflammation and injury markers (transforming growth factor-β, mouse anti-target of antiproliferative antibody-1, and nephrin), whereas ASIC2(+/-) mice had an increase in the remodeling marker collagen type III. Consistent with a more severe loss of function, mean arterial pressure was increased in ASIC2(+/-) mice (131 ± 3 mmHg) but not in ASIC2(-/-) mice (122 ± 3 vs. 117 ± 2 mmHg in ASIC2(+/+) mice). These results suggest that ASIC2 contributes to transduction of the renal myogenic response and are consistent with the protective role of myogenic constriction against renal injury and hypertension. Copyright © 2015 the American Physiological Society.
Food-dependent exercise-induced anaphylaxis with a high level of plasma noradrenaline.

Science.gov (United States)

Kato, Yukihiko; Nagai, Ayako; Saito, Masuyoshi; Ito, Tomonobu; Koga, Michiyuki; Tsuboi, Ryoji

2007-02-01

Ingesting certain foods sometimes triggers anaphylaxis when followed by exercise (food-dependent exercise-induced anaphylaxis, FDEIA). Specific food-induced mucocutaneous urticaria may also progress to anaphylaxis (oral allergy syndrome, OAS). A positive skin test and/or radioallergosorbent test (RAST) to the foods suggest involvement of immunoglobulin (Ig)E-anaphylaxis in both disorders. The triggering foods and initial target organs are usually different in each case. In the present study, a 32-year-old male reported dyspnea accompanied by wheals, and symptoms of low blood pressure while walking after eating Chinese noodles and donuts. He also reported uncomfortable sensations in his mouth and throat after ingesting melon. Exercise challenge tests were administered. Serum histamine, plasma adrenaline, noradrenaline and dopamine were measured pre- and post-test. No symptoms were induced by exercise or by the ingestion of any single food item before exercise. However, numerous wheals appeared when exercise followed the combined ingestion of foods. Likewise, the sequence of eating pancakes and then exercising resulted in numerous wheals and anaphylaxis. Olopatadine hydrochloride and ketotifen fumarate completely inhibited this anaphylaxis. The skin prick tests resulted in fruit-induced erythema and wheals. The results of these tests with wheat, butter and sugar were negative, and no symptoms were induced by the exercise test after ingestion of watermelon, melon or apple. The anaphylactoid symptoms were accompanied by a significant increase of plasma noradrenaline. In this case, not only wheat, but sugar and butter may induce the onset of FDEIA. There was no significant correlation between the intensity of the symptoms and the serum histamine levels in the present case. Noradrenaline may be involved in the onset of FDEIA, since noradrenaline may selectively inhibit T-helper (Th)1 functions while favoring Th2 responses. The tests showed no cross-reactivity between the
Longitudinal changes in reproductive hormones and menstrual cyclicity in cynomolgus monkeys during strenuous exercise training: abrupt transition to exercise-induced amenorrhea.

Science.gov (United States)

Williams, N I; Caston-Balderrama, A L; Helmreich, D L; Parfitt, D B; Nosbisch, C; Cameron, J L

2001-06-01

Cross-sectional studies of exercise-induced reproductive dysfunction have documented a high proportion of menstrual cycle disturbances in women involved in strenuous exercise training. However, longitudinal studies have been needed to examine individual susceptibility to exercise-induced reproductive dysfunction and to elucidate the progression of changes in reproductive function that occur with strenuous exercise training. Using the female cynomolgus monkey (Macaca fascicularis), we documented changes in menstrual cyclicity and patterns of LH, FSH, estradiol, and progesterone secretion as the animals developed exercise-induced amenorrhea. As monkeys gradually increased running to 12.3 +/- 0.9 km/day, body weight did not change significantly although food intake remained constant. The time spent training until amenorrhea developed varied widely among animals (7-24 months; mean = 14.3 +/- 2.2 months) and was not correlated with initial body weight, training distance, or food intake. Consistent changes in function of the reproductive axis occurred abruptly, one to two menstrual cycles before the development of amenorrhea. These included significant declines in plasma reproductive hormone concentrations, an increase in follicular phase length, and a decrease in luteal phase progesterone secretion. These data document a high level of interindividual variability in the development of exercise-induced reproductive dysfunction, delineate the progression of changes in reproductive hormone secretion that occur with exercise training, and illustrate an abrupt transition from normal cyclicity to an amenorrheic state in exercising individuals, that is not necessarily associated with weight loss.
Evidence of a Redox-Dependent Regulation of Immune Responses to Exercise-Induced Inflammation

Directory of Open Access Journals (Sweden)

Alexandra Sakelliou

2016-01-01

Full Text Available We used thiol-based antioxidant supplementation (n-acetylcysteine, NAC to determine whether immune mobilisation following skeletal muscle microtrauma induced by exercise is redox-sensitive in healthy humans. According to a two-trial, double-blind, crossover, repeated measures design, 10 young men received either placebo or NAC (20 mg/kg/day immediately after a muscle-damaging exercise protocol (300 eccentric contractions and for eight consecutive days. Blood sampling and performance assessments were performed before exercise, after exercise, and daily throughout recovery. NAC reduced the decline of reduced glutathione in erythrocytes and the increase of plasma protein carbonyls, serum TAC and erythrocyte oxidized glutathione, and TBARS and catalase activity during recovery thereby altering postexercise redox status. The rise of muscle damage and inflammatory markers (muscle strength, creatine kinase activity, CRP, proinflammatory cytokines, and adhesion molecules was less pronounced in NAC during the first phase of recovery. The rise of leukocyte and neutrophil count was decreased by NAC after exercise. Results on immune cell subpopulations obtained by flow cytometry indicated that NAC ingestion reduced the exercise-induced rise of total macrophages, HLA+ macrophages, and 11B+ macrophages and abolished the exercise-induced upregulation of B lymphocytes. Natural killer cells declined only in PLA immediately after exercise. These results indicate that thiol-based antioxidant supplementation blunts immune cell mobilisation in response to exercise-induced inflammation suggesting that leukocyte mobilization may be under redox-dependent regulation.
Renal myogenic constriction protects the kidney from age-related hypertensive renal damage in the Fawn-Hooded rat

NARCIS (Netherlands)

Vavrinec, Peter; Henning, Robert H.; Goris, Maaike; Landheer, Sjoerd W.; Buikema, Hendrik; van Dokkum, Richard P. E.

Introduction:Intact myogenic constriction plays a role in renal blood flow autoregulation and protection against pressure-related (renal) injury. However, to what extent alterations in renal artery myogenic constriction are involved in development of renal damage during aging is unknown. Therefore,
Increased pain sensitivity but normal function of exercise induced analgesia in hip and knee osteoarthritis - treatment effects of neuromuscular exercise and total joint replacement

DEFF Research Database (Denmark)

Kosek, E; Roos, Ewa M.; Ageberg, E

2013-01-01

To assess exercise induced analgesia (EIA) and pain sensitivity in hip and knee osteoarthritis (OA) and to study the effects of neuromuscular exercise and surgery on these parameters.......To assess exercise induced analgesia (EIA) and pain sensitivity in hip and knee osteoarthritis (OA) and to study the effects of neuromuscular exercise and surgery on these parameters....
Exercise-induced muscle-derived cytokines inhibit mammary cancer cell growth.

Science.gov (United States)

Hojman, Pernille; Dethlefsen, Christine; Brandt, Claus; Hansen, Jakob; Pedersen, Line; Pedersen, Bente Klarlund

2011-09-01

Regular physical activity protects against the development of breast and colon cancer, since it reduces the risk of developing these by 25-30%. During exercise, humoral factors are released from the working muscles for endocrinal signaling to other organs. We hypothesized that these myokines mediate some of the inhibitory effects of exercise on mammary cancer cell proliferation. Serum and muscles were collected from mice after an exercise bout. Incubation with exercise-conditioned serum inhibited MCF-7 cell proliferation by 52% and increased caspase activity by 54%. A similar increase in caspase activity was found after incubation of MCF-7 cells with conditioned media from electrically stimulated myotubes. PCR array analysis (CAPM-0838E; SABiosciences) revealed that seven genes were upregulated in the muscles after exercise, and of these oncostatin M (OSM) proved to inhibit MCF-7 proliferation by 42%, increase caspase activity by 46%, and induce apoptosis. Blocking OSM signaling with anti-OSM antibodies reduced the induction of caspase activity by 51%. To verify that OSM was a myokine, we showed that it was significantly upregulated in serum and in three muscles, tibialis cranialis, gastronemius, and soleus, after an exercise bout. In contrast, OSM expression remained unchanged in subcutaneous and visceral adipose tissue, liver, and spleen (mononuclear cells). We conclude that postexercise serum inhibits mammary cancer cell proliferation and induces apoptosis of these cells. We suggest that one or more myokines secreted from working muscles may be mediating this effect and that OSM is a possible candidate. These findings emphasize that role of physical activity in cancer treatment, showing a direct link between exercise-induced humoral factors and decreased tumor cell growth.
Maintenance of exercise-induced benefits in physical functioning and bone among elderly women.

Science.gov (United States)

Karinkanta, S; Heinonen, A; Sievänen, H; Uusi-Rasi, K; Fogelholm, M; Kannus, P

2009-04-01

This study showed that about a half of the exercise-induced gain in dynamic balance and bone strength was maintained one year after cessation of the supervised high-intensity training of home-dwelling elderly women. However, to maintain exercise-induced gains in lower limb muscle force and physical functioning, continued training seems necessary. Maintenance of exercise-induced benefits in physical functioning and bone structure was assessed one year after cessation of 12-month randomized controlled exercise intervention. Originally 149 healthy women 70-78 years of age participated in the 12-month exercise RCT and 120 (81%) of them completed the follow-up study. Self-rated physical functioning, dynamic balance, leg extensor force, and bone structure were assessed. During the intervention, exercise increased dynamic balance by 7% in the combination resistance and balance-jumping training group (COMB). At the follow-up, a 4% (95% CI: 1-8%) gain compared with the controls was still seen, while the exercise-induced isometric leg extension force and self-rated physical functioning benefits had disappeared. During the intervention, at least twice a week trained COMB subjects obtained a significant 2% benefit in tibial shaft bone strength index compared to the controls. A half of this benefit seemed to be maintained at the follow-up. Exercise-induced benefits in dynamic balance and rigidity in the tibial shaft may partly be maintained one year after cessation of a supervised 12-month multi-component training in initially healthy elderly women. However, to maintain the achieved gains in muscle force and physical functioning, continued training seems necessary.

Myogenic conversion of bladder fibroblasts by construction and ...

African Journals Online (AJOL)

The cultured primary bladder fibroblasts were transfected by pEGFP-Myod1 with Lipofection 2000 reagent. The results showed that expression of Myod1 could cause myogenic differentiation of bladder fibroblasts. These findings support the possibility of an alternative approach to exploit the capacity of Myod1 to activate ...
Effect of birth weight and 12 weeks of exercise training on exercise-induced AMPK signaling in human skeletal muscle

DEFF Research Database (Denmark)

Mortensen, Brynjulf; Hingst, Janne Rasmuss; Frederiksen, Nicklas

2013-01-01

. We investigated 21 LBW and 21 normal birth weight (NBW) subjects during 1 hour of acute exercise performed at the same relative workload before and after 12 weeks of exercise training. Multiple skeletal muscle biopsies were obtained before and after exercise. Protein levels and phosphorylation status......Subjects with a low birth weight (LBW) display increased risk of developing type 2 diabetes (T2D). We hypothesized that this is associated with defects in muscle adaptations following acute and regular physical activity, evident by impairments in the exercise-induced activation of AMPK signaling...... were determined by Western blotting. AMPK activities were measured using activity assays. Protein levels of AMPK isoforms a1 and ¿1 were significantly increased while ¿3 levels decreased with training independent of group. The LBW group had higher exercise-induced AMPK Thr(172) phosphorylation before...
Nonpharmacologic strategies to manage exercise-induced bronchoconstriction

DEFF Research Database (Denmark)

Dickinson, John; Amirav, Israel; Hostrup, Morten

2018-01-01

Pharmacologic management of exercise-induced bronchoconstriction (EIB) is the mainstay of preventative therapy. There are some nonpharmacologic interventions, however, that may assist the management of EIB. This review discusses these nonpharmacologic interventions and how they may be applied to ...
Vitamins C and E for asthma and exercise-induced bronchoconstriction.

Science.gov (United States)

Wilkinson, Mark; Hart, Anna; Milan, Stephen J; Sugumar, Karnam

2014-06-17

The association between dietary antioxidants and asthma or exercise-induced bronchoconstriction (EIB) is not fully understood. Vitamin C and vitamin E are natural antioxidants that are predominantly present in fruits and vegetables; inadequate vitamin E intake is associated with airway inflammation. It has been postulated that the combination may be more beneficial than either single antioxidant for people with asthma and exercise-induced bronchoconstriction. To assess the effects of supplementation of vitamins C and E versus placebo (or no vitamin C and E supplementation) on exacerbations and health-related quality of life (HRQL) in adults and children with chronic asthma. To also examine the potential effects of vitamins C and E on exercise-induced bronchoconstriction in people with asthma and in people without a diagnosis of asthma who experience symptoms only on exercise. Trials were identified from the Cochrane Airways Review Group Specialised Register and from trial registry websites. Searches were conducted in September 2013. We included randomised controlled trials of adults and children with a diagnosis of asthma. We separately considered trials in which participants had received a diagnosis of exercise-induced bronchoconstriction (or exercise-induced asthma). Trials comparing vitamin C and E supplementation versus placebo were included. We included trials in which asthma management for treatment and control groups included similar background therapy. Short-term use of vitamins C and E at the time of exacerbation or for cold symptoms in people with asthma is outside the scope of this review. Two review authors independently screened the titles and abstracts of potential studies and subsequently screened full-text study reports for inclusion. We used standard methods as expected by The Cochrane Collaboration. It was not possible to aggregate the five included studies (214 participants). Four studies (206 participants) addressed the question of whether
Does chronic smoking affect induced-exercise catecholamine release?

Directory of Open Access Journals (Sweden)

Gökhan İpekoğlu

2017-04-01

Full Text Available This study was performed to investigate the acute effect of the submaximal aerobic exercise upon epinephrine and nor-epinephrine levels in chronic smokers and non-smoker. The study was carried out upon 10 regular (15> cigarettes/day smoker untrained male along five years and 10 never smoker untrained male. Subjects performed an endurance exercise that continues 40 minutes at 70% maximal heart rate. There were 15cc venous blood samples extracted from the forearm pre-exercise (PRE, post-exercise (POST, post-exercise 2 hours (2h, post-exercise 24 hours (24h to measure of epinephrine and nor-epinephrine levels. The plasma level of each hormone increased after exercise and the tendency of rise was similar between groups as it seen in which 55,6% and 54,68% for epinephrine and 27,1% and 35,7% for norepinephrine. In this respect no group-time relationship has been found (p>0,05. But in between-group analyses, basal and after exercise levels were different (p<0,05. The study revealed the fact that, smokers have higher plasma levels of epinephrine and norepinephrine before and after exercise. The results demonstrate that long-term smoking induces elevate baseline and post-aerobic submaximal exercise plasma epinephrine and nor-epinephrine levels. The sympatho-adrenal activity appears to be disrupt with long-term smoking which effect the glycolytic and fat metabolism during exercise.
High Prevalence of Exercise-Induced Laryngeal Obstruction in Athletes

DEFF Research Database (Denmark)

Walsted Nielsen, Emil; Hull, James H; Backer, Vibeke

2013-01-01

INTRODUCTION: Unexplained respiratory symptoms reported by athletes are often incorrectly considered secondary to exercise-induced asthma. We hypothesised that this may be related to exercise induced laryngeal obstruction (EILO). This study evaluates the prevalence of EILO in an unselected cohort......-one percent of athletes with EILO and negative bronchoprovocation and bronchodilator reversibility tests used regular asthma medication at referral. CONCLUSION: In athletes with unexplained respiratory symptoms, EILO is an important differential diagnosis not discerned from other aetiologies by clinical...... features. These findings have important implications for the assessment and management of athletes presenting with persistent respiratory symptoms despite asthma therapy....
Evaluation of the effects of different culture media on the myogenic differentiation potential of adipose tissue- or bone marrow-derived human mesenchymal stem cells.

Science.gov (United States)

Stern-Straeter, Jens; Bonaterra, Gabriel Alejandro; Juritz, Stephanie; Birk, Richard; Goessler, Ulrich Reinhart; Bieback, Karen; Bugert, Peter; Schultz, Johannes; Hörmann, Karl; Kinscherf, Ralf; Faber, Anne

2014-01-01

-MSCs. The strongest DES expression was observed using the 30% conditioned cell culture medium. The detection of myogenic markers using different cell culture media as stimuli was only achieved in the AT-MSCs, but not in the BM-MSCs. The strongest myogenic differentiation, in terms of the markers examined, was induced by the 30% conditioned cell culture medium.
Experience affects exercise-induced changes in catecholamines, glucose, and FFA

NARCIS (Netherlands)

Scheurink, A.J.W.; Steffens, A.B.; Dreteler, G.H.; Benthem, L.; Bruntink, R.

The interference of the experimental conditions on the exercise-induced alterations in plasma catecholamines, plasma free fatty acids, and glucose and insulin concentrations was investigated in rats. Exercise consisted of strenuous swimming against a countercurrent (0.22 m/s) for 15 min in a pool
The role of low-energy electrons in focused electron beam induced deposition: four case studies of representative precursors

Directory of Open Access Journals (Sweden)

Rachel M. Thorman

2015-09-01

Full Text Available Focused electron beam induced deposition (FEBID is a single-step, direct-write nanofabrication technique capable of writing three-dimensional metal-containing nanoscale structures on surfaces using electron-induced reactions of organometallic precursors. Currently FEBID is, however, limited in resolution due to deposition outside the area of the primary electron beam and in metal purity due to incomplete precursor decomposition. Both limitations are likely in part caused by reactions of precursor molecules with low-energy (3, Pt(PF34, Co(CO3NO, and W(CO6. Through these case studies, it is evident that this combination of studies can provide valuable insight into potential mechanisms governing deposit formation in FEBID. Although further experiments and new approaches are needed, these studies are an important stepping-stone toward better understanding the fundamental physics behind the deposition process and establishing design criteria for optimized FEBID precursors.
Laser damage in optical components: metrology, statistical and photo-induced analysis of precursor centres

International Nuclear Information System (INIS)

Gallais, L.

2002-11-01

This thesis deals with laser damage phenomena for nanosecond pulses, in optical components such as glasses, dielectric and metallic thin films. Firstly, a work is done on the laser damage metrology, in order to obtain accurate and reliable measurement of laser-induced damage probabilities, with a rigorous control of test parameters. Then, with the use of a specific model, we find densities of laser damage precursors in the case of bulk glasses (few tens by (100μm) 3 ) and in the case of glass surfaces (one precursor by μm 3 ). Our analysis is associated to morphology studies by Atomic Force Microscope to discuss about precursor nature and damage process. Influence of wavelength (from 355 to 1064 nm) and cumulated shots is also studied. Simulations are performed to study initiation mechanisms on these inclusions. This work gives an estimation of complex index and size of the precursor, which permits to discuss about possible detection by non-destructive tools. (author)
Effect of Submaximal Warm-up Exercise on Exercise-induced Asthma in African School Children.

Science.gov (United States)

Mtshali, B F; Mokwena, K; Oguntibeju, O O

2015-03-01

Regular physical activity has long been regarded as an important component of a healthy lifestyle. Exercise-induced asthma (EIA) is one of the major problems interfering with the performance of exercise. A warm-up exercise programme has been cited as a non-pharmacologic means of reducing EIA, but its effect has not been fully elucidated. The aims of this study were to determine the prevalence of unrecognized EIA in Pretoria primary school children, determine the effect of a warm-up exercise programme on EIA and to establish the relationship between history of allergy, family history of asthma and EIA. A random sample of 640 school children was selected. The study was divided into three phases. In phase one, a descriptive cross-sectional study was done using the standardized European Community Respiratory Health Survey (ECRHS) questionnaire. In phase two, non-asthmatic participants that returned a completed questionnaire were included in the field study. Pre-test and post-test experimental designs were used, where peak expiratory flow rate (PEFR) was measured at baseline and within ten minutes after exercise. A total of 340 subjects completed the Free Running Asthma Screening Test (FRAST); EIA was defined as a decrease in baseline PEFR ≥ 10% after exercise and 75 children (22%) had EIA. In phase three, 29 of the 75 subjects participated in the warm-up programme which was performed in the laboratory and subjects acted as their own controls. Predefined protocols for the study were followed. Seventy-five (22%) of the 340 participants had EIA. The mean age, height and weight were 10.51 years, 139.26 cm and 33.45 kg, respectively. Exercise-induced asthma symptoms were cough (25%), chest pain (16%), wheeze (12%) and chest tightness (12%). The history of allergy was 75%, family history of allergy 40% and positive history of allergy when near animals, feathers or in dusty areas 38%. Wheezing during or after exercise, wheezing when near animals, feathers or in dusty areas
Exercise-Induced Bronchospasm and Allergy

Directory of Open Access Journals (Sweden)

Serena Caggiano

2017-06-01

Full Text Available Sport is an essential part of childhood, with precious and acknowledged positive health effects but the impact of exercise-induced bronchoconstriction (EIB significantly reduces participation in physical activity. It is important to recognize EIB, differentiating EIB with or without asthma if the transient narrowing of the airways after exercise is associated with asthmatic symptoms or not, in the way to select the most appropriate treatment among the many treatment options available today. Therapy is prescribed based on symptoms severity but diagnosis of EIB is established by changes in lung function provoked by exercise evaluating by direct and indirect tests. Sometimes, in younger children it is difficult to obtain the registration of difference between the preexercise forced expiratory volume in the first second (FEV1 value and the lowest FEV1 value recorded within 30 min after exercise, defined as the gold standard, but interrupter resistance, in association with spirometry, has been showed to be a valid alternative in preschool age. Atopy is the main risk factor, as demonstrated by epidemiologic data showing that among the estimated pediatric population with EIB up to 40% of them have allergic rhinitis and 30% of these patients may develop adult asthma, according with atopic march. Adopting the right treatment and prevention, selecting sports with no marked hyperventilation and excessive cooling of the airways, children with EIB can be able to take part in physical activity like all others.
A nonlinear model for myogenic regulation of blood flow to bone: equilibrium states and stability characteristics.

Science.gov (United States)

Harrigan, T P

1996-01-01

A simple compartmental model for myogenic regulation of interstitial pressure in bone is developed, and the interaction between changes in interstitial pressure and changes in arterial and venous resistance is studied. The arterial resistance is modeled by a myogenic model that depends on transmural pressure, and the venous resistance is modeled by using a vascular waterfall. Two series capacitances model blood storage in the vascular system and interstitial fluid storage in the extravascular space. The static results mimic the observed effect that vasodilators work less well in bone than do vasoconstrictors. The static results also show that the model gives constant flow rates over a limited range of arterial pressure. The dynamic model shows unstable behavior at small values of bony capacitance and at high enough myogenic gain. At low myogenic gain, only a single equilibrium state is present, but a high enough myogenic gain, two new equilibrium states appear. At additional increases in gain, one of the two new states merges with and then separates from the original state, and the original state becomes a saddle point. The appearance of the new states and the transition of the original state to a saddle point do not depend on the bony capacitance, and these results are relevant to general fluid compartments. Numerical integration of the rate equations confirms the stability calculations and shows limit cycling behavior in several situations. The relevance of this model to circulation in bone and to other compartments is discussed.
Normalization reduces intersubject variability in cervical vestibular evoked myogenic potentials.

Science.gov (United States)

van Tilburg, Mark J; Herrmann, Barbara S; Guinan, John J; Rauch, Steven D

2014-09-01

Cervical vestibular evoked myogenic potentials are used to assess saccular and inferior vestibular nerve function. Normalization of the VEMP waveform has been proposed to reduce the variability in vestibular evoked myogenic potentials by correcting for muscle activation. In this study, we test the hypothesis that normalization of the raw cervical VEMP waveform causes a significant decrease in the intersubject variability. Prospective cohort study. Large specialty hospital, department of otolaryngology. Twenty healthy subjects were used in this study. All subjects underwent cervical vestibular evoked myogenic potential testing using short tone bursts at 250, 500, 750, and 1,000 Hz. Both intersubject and intrasubject variability was assessed. Variability between raw and normalized peak-to-peak amplitudes was compared using the coefficient of variation. Intrasubject variability was assessed using the intraclass correlation coefficient and interaural asymmetry ratio. cVEMPs were present in most ears. Highest peak-to-peak amplitudes were recorded at 750 Hz. Normalization did not alter cVEMP tuning characteristics. Normalization of the cVEMP response caused a significant reduction in intersubject variability of the peak-to-peak amplitude. No significant change was seen in the intrasubject variability. Normalization significantly reduces cVEMP intersubject variability in healthy subjects without altering cVEMP characteristics. By reducing cVEMP amplitude variation due to nonsaccular, muscle-related factors, cVEMP normalization is expected to improve the ability to distinguish between healthy and pathologic responses in the clinical application of cVEMP testing.
Acute exercise induces biphasic increase in respiratory mRNA in skeletal muscle

International Nuclear Information System (INIS)

Ikeda, Shin-ichi; Kizaki, Takako; Haga, Shukoh; Ohno, Hideki; Takemasa, Tohru

2008-01-01

Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) promotes the expression of oxidative enzymes in skeletal muscle. We hypothesized that activation of the p38 MAPK (mitogen-activated protein kinase) in response to exercise was associated with exercise-induced PGC-1α and respiratory enzymes expression and aimed to demonstrate this under the physiological level. We subjected mice to a single bout of treadmill running and found that the exercise induced a biphasic increase in the expression of respiratory enzymes mRNA. The second phase of the increase was accompanied by an increase in PGC-1α protein, but the other was not. Administration of SB203580 (SB), an inhibitor of p38 MAPK, suppressed the increase in PGC-1α expression and respiratory enzymes mRNA in both phases. These data suggest that p38 MAPK is associated with the exercise-induced expression of PGC-1α and biphasic increase in respiratory enzyme mRNAs in mouse skeletal muscle under physiological conditions
Fasting- and Exercise-Induced PDH Regulation in Skeletal Muscle

DEFF Research Database (Denmark)

Gudiksen, Anders

in selected mitochondrial proteins. Lastly, increased oxidative capacity leads to exercise-induced skeletal muscle PDH activation that is closely matched to the relative exercise intensity at submaximal exercise, while reaching a higher level at maximal exercise in trained individuals. These responses......Pyruvate dehydrogenase PDH constitutes the only mammalian pathway for irreversible conversion of pyruvate to acetyl-CoA thus providing the vital link between glycolytic energy production, the TCA cycle, and oxidative phosphorylation. Because the PDC controls the conversion of pyruvate it occupies...... a central position in relation to the control of mitochondrial energy production and cellular substrate metabolism. Suppression and activation of PDH becomes essential in situations where glucose availability and/or use changes with swift and appropriate regulation of the complex to maintain energy...
One arm exercise induces significant interarm diastolic blood pressure difference.

Science.gov (United States)

Hong, Dezhi; Wang, Jiwei; Su, Hai; Xu, Jingsong; Liu, Yanna; Peng, Qiang; Wang, Lijuan

2011-06-01

This study is designed to investigate the inducing effect of one arm exercise on interarm difference (IAD) in the blood pressure (BP). Fifty healthy young participants were included in the study. Three-minute exercises of the right arm elbow flexion and extension were performed. The bilateral brachial BP was simultaneously measured with two automatic BP measurement devices before (basic) and immediately 0, 5, 10, 15, 20, and 30 min after exercise. The absolute difference in the systolic BP (SBP) and diastolic BP (DBP) between the left and right BP of at least 10 mmHg was recognized as sIAD and dIAD. The baseline data of the SBP and DBP in left and right arms revealed no significant difference (SBP: 110 ± 10 vs. 111 ± 11 mmHg; DBP: 66 ± 8 vs. 66 ± 9 mmHg, both not significant). The prevalence of dIAD was 2% at the baseline. However, this prevalence increased to 80% at 0 min, as right arm exercise induced the right DBP decrease and left DBP increase, and then the prevalence decreased gradually within a 30-min recovery period. The prevalence of sIAD was zero at the baseline and the maximal prevalence was 8% during the 20-min postexercise period. One arm exercise can lead to a significant IAD in DBP. Any arm exercise should be avoided before BP measurement.
Role of myocardial ischemia on exercise-induced ST elevation

International Nuclear Information System (INIS)

Saito, Muneyasu; Sumiyoshi, Tetsuya; Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kouhei; Haze, Kazuo; Fukami, Ken-ichi; Hiramori, Katsuhiko

1986-01-01

Exercise-induced ST elevation in patients with previous myocardial infarction (MI) has been recognized to be related to left ventricular (LV) asynergy, however it is also recognized that myocardial ischemia can induce ST elevation. In this study, factors which determine the extent of ST elevation, with special reference to myocardial ischemia, was re-evaluated using quantitative analysis of stress myocardial scintigraphy (S-SG). Among 65 patients with previous anterior myocardial infarction and documented single vessel disease of left anterior descending artery (LAD), 19 patients who had exercise-induced ST elevation (ΔST ≥ 2.0 mm) had more abnormal Q waves (p < 0.01), lower LV ejection fraction (EF) (p < 0.01), more severe LV asynergy (p < 0.05) and less incidence of post-MI angina pectoris (AP) (p < 0.01), compared to those with ΔST < 2.0 mm, indicating that ST elevation is primarily related to LV asynergy. Correlation studies among clinical, angiographic and scintigraphic parameters show that ΔST was significantly related to a size of MI represented by Tl score or relative defect Tl activity and number of abnormal Q waves (No.Q), the magnitude of work load expressed by changes in double product (ΔDP) and intervals between the onset and exercise test, as well as myocardial ischemia expressed by the extent of redistribution (%RD) in S-SG. Among 23 patients with post-MI AP, ΔST significantly correlated with %RD (r = 0.47), indicating that myocardial ischemia can be a mechanism of exercise-induced ST elevation in patients with previous MI. Furtheremore, among those with ST elevation, concave-type ST elevation was more related to myocardial ischemia compared to convex-type ST elevation as expressed by the incidence of post-MI AP and/or significant redistribution. (J.P.N.)
Lipopolysaccharide inhibits myogenic differentiation of C2C12 myoblasts through the Toll-like receptor 4-nuclear factor-κB signaling pathway and myoblast-derived tumor necrosis factor-α.

Directory of Open Access Journals (Sweden)

Yuko Ono

Full Text Available Circulating lipopolysaccharide (LPS concentrations are often elevated in patients with sepsis or with various endogenous diseases that are associated with metabolic endotoxemia. Involuntary loss of skeletal muscle, termed muscle wasting, is commonly observed in these conditions, suggesting that circulating LPS might play an essential role in its development. Although impairment of muscle regeneration is an important determinant of skeletal muscle wasting, it is unclear whether LPS affects this process and, if so, by what mechanism. Here, we used the C2C12 myoblast cell line to investigate the effects of LPS on myogenesis.C2C12 myoblasts were grown to 80% confluence and induced to differentiate in the absence or presence of LPS (0.1 or 1 μg/mL; TAK-242 (1 μM, a specific inhibitor of Toll-like receptor 4 (TLR4 signaling; and a tumor necrosis factor (TNF-α neutralizing antibody (5 μg/mL. Expression of a skeletal muscle differentiation marker (myosin heavy chain II, two essential myogenic regulatory factors (myogenin and MyoD, and a muscle negative regulatory factor (myostatin was analyzed by western blotting. Nuclear factor-κB (NF-κB DNA-binding activity was measured using an enzyme-linked immunosorbent assay.LPS dose-dependently and significantly decreased the formation of multinucleated myotubes and the expression of myosin heavy chain II, myogenin, and MyoD, and increased NF-κB DNA-binding activity and myostatin expression. The inhibitory effect of LPS on myogenic differentiation was reversible, suggesting that it was not caused by nonspecific toxicity. Both TAK-242 and anti-TNF-α reduced the LPS-induced increase in NF-κB DNA-binding activity, downregulation of myogenic regulatory factors, and upregulation of myostatin, thereby partially rescuing the impairment of myogenesis.Our data suggest that LPS inhibits myogenic differentiation via a TLR4-NF-κB-dependent pathway and an autocrine/paracrine TNF-α-induced pathway. These pathways
Assessment of D-methionine protecting cisplatin-induced otolith toxicity by vestibular-evoked myogenic potential tests, ATPase activities and oxidative state in guinea pigs.

Science.gov (United States)

Lo, Wu-Chia; Chang, Chih-Ming; Liao, Li-Jen; Wang, Chi-Te; Young, Yi-Ho; Chang, Yih-Leong; Cheng, Po-Wen

2015-01-01

To date, inadequate study has been devoted to the toxic vestibular effects caused by cisplatin. In addition, no electrophysiological examination has been conducted to assess cisplatin-induced otolith toxicity. The purposes of this study are thus two-fold: 1) to determine whether cervical vestibular-evoked myogenic potentials (VEMPs) and ocular VEMPs are practical electrophysiological methods of testing for cisplatin-induced otolith toxicity and 2) to examine if D-methionine (D-met) pre-injection would protect the otolith organs against cisplatin-induced changes in enzyme activities and/or oxidative status. Guinea pigs were intraperitoneally treated once daily with the following injections for seven consecutive days: sterile 0.9% saline control, cisplatin (5 mg/kg) only, D-met (300 mg/kg) only, or a combination of d-met (300 mg/kg) and cisplatin (5 mg/kg), respectively, with a 30 minute window in between. Each animal underwent the oVEMP and cVEMP tests before and after treatment. The changes in the biochemistry of the otolith organs, including membranous Na(+), K(+)-ATPase and Ca(2+)-ATPase, lipid peroxidation (LPO) levels and nitric oxide (NO) levels, were also evaluated. In the cisplatin-only treated guinea pigs, the mean amplitudes of the oVEMP tests were significantly (potolith dysfunction. D-Met attenuated the reduced ATPase activities and increased oxidative stress induced by cisplatin toxicity in the otolith organs. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of naloxone opiate blockade on the immunomodulation induced by exercise in rats.

Science.gov (United States)

Bouix, O; elMezouini, M; Orsetti, A

1995-01-01

The purpose of this study was to examine the possible involvement of the endogenous opiate system in the changes in immune competence induced by isolated exercise. Male untrained rats were subjected to a 2.5 hours swimming exercise bout. Animals were killed 15 min after the end of the exercise. The concentration of leukocytes, lymphocytes, monocytes and granulocytes and T4 (T-helper), T8 (T-suppressor/cytotoxic), interleukin-2 receptor (IL-2R) and transferrin receptor (TrfR) positive lymphocytes were determined both in peripheral blood and spleen by flow cytometric analysis. Exercise resulted in a significant decrease in 1) blood lymphocyte and splenic granulocyte number (p exercising rats induced a decrease in the concentration and proportion of T8 positive lymphocytes, thereby restoring a normal T4/T8 ratio both in peripheral blood and spleen. Naloxone had no effect in control animals. The concentration and proportion of IL-2R and TrfR positive lymphocytes were not affected by naloxone. The mechanisms of the immunomodulation induced by isolated intense exercise are unclear. These data suggest that endogenous opiates participate in the alteration of cell-mediated immunity associated with exercise by modulating the T8 (suppressor/cytotoxic)-cell activity.
Efficient electron-induced removal of oxalate ions and formation of copper nanoparticles from copper(II oxalate precursor layers

Directory of Open Access Journals (Sweden)

Kai Rückriem

2016-06-01

Full Text Available Copper(II oxalate grown on carboxy-terminated self-assembled monolayers (SAM using a step-by-step approach was used as precursor for the electron-induced synthesis of surface-supported copper nanoparticles. The precursor material was deposited by dipping the surfaces alternately in ethanolic solutions of copper(II acetate and oxalic acid with intermediate thorough rinsing steps. The deposition of copper(II oxalate and the efficient electron-induced removal of the oxalate ions was monitored by reflection absorption infrared spectroscopy (RAIRS. Helium ion microscopy (HIM reveals the formation of spherical nanoparticles with well-defined size and X-ray photoelectron spectroscopy (XPS confirms their metallic nature. Continued irradiation after depletion of oxalate does not lead to further particle growth giving evidence that nanoparticle formation is primarily controlled by the available amount of precursor.
Adaptation of exercise-induced stress in well-trained healthy young men

NARCIS (Netherlands)

Janssen Duijghuijsen, L.M.; Keijer, J.; Mensink, M.R.; Lenaerts, Kaatje; Ridder, L.O.; Nierkens, Stefan; Kartaram, Shirley; Verschuren, Martie C.M.; Pieters, Raymond; Bas, Richard; Witkamp, R.F.; Wichers, H.J.; Norren, van K.

2017-01-01

Strenuous exercise induces different stress-related physiological changes, potentially including changes in intestinal barrier function. In the Protégé Study (ISRCTN14236739; www.isrctn.com) we determined the test-retest repeatability in responses to exercise in well-trained individuals.
Eleven
Adaptation of exercise-induced stress in well-trained healthy young men

NARCIS (Netherlands)

JanssenDuijghuijsen, Lonneke M; Keijer, Jaap; Mensink, Marco; Lenaerts, Kaatje; Ridder, Lars; Nierkens, Stefan; Kartaram, Shirley W; Verschuren, Martie C M; Pieters, Raymond H H; Bas, Richard; Witkamp, Renger F; Wichers, Harry J; van Norren, Klaske

2017-01-01

Strenuous exercise induces different stress-related physiological changes, potentially including changes in intestinal barrier function. In the Protégé Study (ISRCTN14236739; www.isrctn.com) we determined the test-retest repeatability in responses to exercise in well-trained individuals. Eleven
Pharmacologic Strategies for Exercise-Induced Bronchospasm with a Focus on Athletes

DEFF Research Database (Denmark)

Backer, Vibeke; Mastronarde, John

2018-01-01

Exercise-induced bronchoconstriction (EIB) is the transient narrowing of the airways during and after exercise that occurs in response to increased ventilation in susceptible individuals. It occurs across the age spectrum in patients with underlying asthma and can occur in athletes without baseline...
Colostrum supplementation protects against exercise - induced oxidative stress in skeletal muscle in mice

Directory of Open Access Journals (Sweden)

Appukutty Mahenderan

2012-11-01

Full Text Available Abstract Background This study examined the effects of bovine colostrum on exercise –induced modulation of antioxidant parameters in skeletal muscle in mice. Adult male BALB/c mice were randomly divided into four groups (control, colostrum alone, exercise and exercise with colostrum and each group had three subgroups (day 0, 21 and 42. Colostrum groups of mice were given a daily oral supplement of 50 mg/kg body weight of bovine colostrum and the exercise group of mice were made to exercise on the treadmill for 30 minutes per day. Total antioxidants, lipid hydroperoxides, xanthine oxidase and super oxide dismutase level was assayed from the homogenate of hind limb skeletal muscle. Results Exercise—induced a significant oxidative stress in skeletal muscles as evidenced by the elevated lipid hydroperoxides and xanthine oxidase levels. There was a significant decrease in skeletal muscle total antioxidants and superoxide dismutase levels. Daily colostrum supplement significantly reduced the lipid hydroperoxides and xanthine oxidase enzyme level and increased the total antioxidant levels in the leg muscle. Conclusion Thus, the findings of this study showed that daily bovine colostrum supplementation was beneficial to skeletal muscle to reduce the oxidant-induced damage during muscular exercise.
Induction of Skin-Derived Precursor Cells from Human Induced Pluripotent Stem Cells.

Science.gov (United States)

Sugiyama-Nakagiri, Yoriko; Fujimura, Tsutomu; Moriwaki, Shigeru

2016-01-01

The generation of full thickness human skin from dissociated cells is an attractive approach not only for treating skin diseases, but also for treating many systemic disorders. However, it is currently not possible to obtain an unlimited number of skin dermal cells. The goal of this study was to develop a procedure to produce skin dermal stem cells from induced pluripotent stem cells (iPSCs). Skin-derived precursor cells (SKPs) were isolated as adult dermal precursors that could differentiate into both neural and mesodermal progenies and could reconstitute the dermis. Thus, we attempted to generate SKPs from iPSCs that could reconstitute the skin dermis. Human iPSCs were initially cultured with recombinant noggin and SB431542, an inhibitor of activin/nodal and TGFβ signaling, to induce neural crest progenitor cells. Those cells were then treated with SKP medium that included CHIR99021, a WNT signal activator. The induction efficacy from neural crest progenitor cells to SKPs was more than 97%. No other modifiers tested were able to induce those cells. Those human iPSC-derived SKPs (hiPSC-SKPs) showed a similar gene expression signature to SKPs isolated from human skin dermis. Human iPSC-SKPs differentiated into neural and mesodermal progenies, including adipocytes, skeletogenic cell types and Schwann cells. Moreover, they could be induced to follicular type keratinization when co-cultured with human epidermal keratinocytes. We here provide a new efficient protocol to create human skin dermal stem cells from hiPSCs that could contribute to the treatment of various skin disorders.
Clinical significance of plasminogen activator inhibitor activity in patients with exercise-induced ischemia

International Nuclear Information System (INIS)

Sakata, K.; Kurata, C.; Taguchi, T.; Suzuki, S.; Kobayashi, A.; Yamazaki, N.; Rydzewski, A.; Takada, Y.; Takada, A.

1990-01-01

To assess the fibrinolytic system in patients with exercise-induced ischemia and its relation to ischemia and severity of coronary artery disease (CAD), 47 patients with CAD confirmed by results of coronary angiography underwent symptom-limited multistage exercise thallium-201 emission computed tomography. All patients with CAD had exercise-induced ischemia as assessed from thallium-201 images. Pre- and peak exercise blood samples from each patient and preexercise blood samples from control subjects were assayed for several fibrinolytic components and were also assayed for plasma adrenaline. The extent of ischemia was defined as delta visual uptake score (total visual uptake score in delayed images minus total visual uptake score in initial images) and the severity of CAD as the number of diseased vessels. In the basal condition, plasminogen activator inhibitor (PAI) activity was significantly higher in patients with exercise-induced ischemia as compared to control subjects (p less than 0.01), although there were no significant differences in other fibrinolytic variables between the two groups. Moreover, PAI activity in the basal condition displayed a significantly positive correlation with the extent of ischemia (r = 0.47, p less than 0.01). Patients with exercise-induced ischemia were divided into two groups (24 with single-vessel disease and 23 with multivessel disease). There were no significant differences in coronary risk factors, hemodynamics, or plasma adrenaline levels during exercise between single-vessel and multivessel disease except that delta visual uptake score was significantly higher in multivessel disease (p less than 0.01)
Effect of caffeine on vestibular evoked myogenic potential: a systematic review with meta-analysis.

Science.gov (United States)

Souza, Maria Eduarda Di Cavalcanti Alves de; Costa, Klinger Vagner Teixeira da; Menezes, Pedro de Lemos

2017-12-24

Caffeine can be considered the most consumed drug by adults worldwide, and can be found in several foods, such as chocolate, coffee, tea, soda and others. Overall, caffeine in moderate doses, results in increased physical and intellectual productivity, increases the capacity of concentration and reduces the time of reaction to sensory stimuli. On the other hand, high doses can cause noticeable signs of mental confusion and error induction in intellectual tasks, anxiety, restlessness, muscle tremors, tachycardia, labyrinthine changes, and tinnitus. Considering that the vestibular evoked myogenic potential is a clinical test that evaluates the muscular response of high intensity auditory stimulation, the present systematic review aimed to analyze the effects of caffeine on vestibular evoked myogenic potential. This study consisted of the search of the following databases: MEDLINE, CENTRAL, ScienceDirect, Scopus, Web of Science, LILACS, SciELO and ClinicalTrials.gov. Additionally, the gray literature was also searched. The search strategy included terms related to intervention (caffeine or coffee consumption) and the primary outcome (vestibular evoked myogenic potential). Based on the 253 potentially relevant articles identified through the database search, only two full-text publications were retrieved for further evaluation, which were maintained for qualitative analysis. Analyzing the articles found, caffeine has no effect on vestibular evoked myogenic potential in normal individuals. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.
Flavanol-rich cocoa consumption enhances exercise-induced executive function improvements in humans.

Science.gov (United States)

Tsukamoto, Hayato; Suga, Tadashi; Ishibashi, Aya; Takenaka, Saki; Tanaka, Daichi; Hirano, Yoshitaka; Hamaoka, Takafumi; Goto, Kazushige; Ebi, Kumiko; Isaka, Tadao; Hashimoto, Takeshi

2018-02-01

Aerobic exercise is known to acutely improve cognitive functions, such as executive function (EF) and memory function (MF). Additionally, consumption of flavanol-rich cocoa has been reported to acutely improve cognitive function. The aim of this study was to determine whether high cocoa flavanol (CF; HCF) consumption would enhance exercise-induced improvement in cognitive function. To test this hypothesis, we examined the combined effects of HCF consumption and moderate-intensity exercise on EF and MF during postexercise recovery. Ten healthy young men received either an HCF (563 mg of CF) or energy-matched low CF (LCF; 38 mg of CF) beverage 70 min before exercise in a single-blind counterbalanced manner. The men then performed moderate-intensity cycling exercise at 60% of peak oxygen uptake for 30 min. The participants performed a color-word Stroop task and face-name matching task to evaluate EF and MF, respectively, during six time periods throughout the experimental session. EF significantly improved immediately after exercise compared with before exercise in both conditions. However, EF was higher after HCF consumption than after LCF consumption during all time periods because HCF consumption improved EF before exercise. In contrast, HCF consumption and moderate-intensity exercise did not improve MF throughout the experiment. The present findings demonstrated that HCF consumption before moderate-intensity exercise could enhance exercise-induced improvement in EF, but not in MF. Therefore, we suggest that the combination of HCF consumption and aerobic exercise may be beneficial for improving EF. Copyright © 2017 Elsevier Inc. All rights reserved.
Effects of Exercise on Oxidative Stress in Rats Induced by Ozone

Directory of Open Access Journals (Sweden)

Catalina Martinez-Campos

2012-01-01

Full Text Available Oxidative stress (OS induced by acute exercise is reduced by chronic exercise. Ozone (O3 exposure produces OS. The aim of this study was to determine if aerobic exercise (AE reduced OS produced by O3. A pilot experiment was performed with male Wistar rats submitted to AE (trained to swim 90 min/day. Adaptation to exercise was demonstrated three weeks after training by means of changes in reduced nitrates (NOx in plasma. Therefore, two-week training was chosen for the following experiments. Six of twelve trained rats were exposed to O3 (0.5 ppm, 4 h/day, one hour before exercise. Two groups of sedentary animals (n=6 each were used as controls, one of which was exposed to O3. At the end of the experiments NOx, 8-isoprostane (8-IP, malondialdehyde (MDA, superoxide dismutase (SOD activity, and carbonyls (CBs were measured in plasma. CBs did not change in any group. O3-induced OS was manifested by reduced NOx and SOD activity, as well as increased 8-IP and MDA. Exercise significantly blocked O3 effects although SOD was also decreased by exercise (a greater drop occurring in the O3 group. It is concluded that AE protects against OS produced by O3 and the effect is independent of SOD.
The Role of Episodic Postprandial Peptides in Exercise-Induced Compensatory Eating.

Science.gov (United States)

Gibbons, Catherine; Blundell, John E; Caudwell, Phillipa; Webb, Dominic-Luc; Hellström, Per M; Näslund, Erik; Finlayson, Graham

2017-11-01

Prolonged physical activity gives rise to variable degrees of body weight and fat loss, and is associated with variability in appetite control. Whether these effects are modulated by postprandial, peptides is unclear. We examined the role of postprandial peptide response in compensatory eating during 12 weeks of aerobic exercise and in response to high-fat, low-carbohydrate (HFLC) and low-fat, high-carbohydrate (LFHC) meals. Of the 32 overweight/obese individuals, 16 completed 12 weeks of aerobic exercise and 16 nonexercising control subjects were matched for age and body mass index. Exercisers were classified as responders or nonresponders depending on net energy balance from observed compared with expected body composition changes from measured energy expenditure. Plasma samples were collected before and after meals to compare profiles of total and acylated ghrelin, insulin, cholecystokinin, glucagon-like peptide 1 (GLP-1), and total peptide YY (PYY) between HFLC and LFHC meals, pre- and postexercise, and between groups. No differences between pre- and postintervention peptide release. Responders had greater suppression of acylated ghrelin (P exercise. Responders to exercise-induced weight loss showed greater suppression of acylated ghrelin and greater release of GLP-1 and total PYY at baseline. Therefore, episodic postprandial peptide profiles appear to form part of the pre-existing physiology of exercise responders and suggest differences in satiety potential may underlie exercise-induced compensatory eating. Copyright © 2017 Endocrine Society
Nonpharmacologic Strategies to Manage Exercise-Induced Bronchoconstriction.

Science.gov (United States)

Dickinson, John; Amirav, Israel; Hostrup, Morten

2018-05-01

Pharmacologic management of exercise-induced bronchoconstriction (EIB) is the mainstay of preventative therapy. There are some nonpharmacologic interventions, however, that may assist the management of EIB. This review discusses these nonpharmacologic interventions and how they may be applied to patients and athletes with EIB. Copyright © 2018 Elsevier Inc. All rights reserved.
Vestibular-evoked myogenic potentials in miniature pigs

Directory of Open Access Journals (Sweden)

Xi Shi

2016-06-01

Conclusion: The latencies and thresholds of VEMPs recorded from the neck extensor muscle and the masseter muscle appear to be comparable in normal adult Bama miniature pigs, although the amplitude recorded from the neck extensor muscle seems to be higher than that from the masseter muscle. However, because of their usually relatively superficial and easily accessible location, as well as their large volume and strong contractions, masseter muscles may be better target muscles for recording myogenic potentials.
IGF-1 deficiency impairs cerebral myogenic autoregulation in hypertensive mice.

Science.gov (United States)

Toth, Peter; Tucsek, Zsuzsanna; Tarantini, Stefano; Sosnowska, Danuta; Gautam, Tripti; Mitschelen, Matthew; Koller, Akos; Sonntag, William E; Csiszar, Anna; Ungvari, Zoltan

2014-12-01

Aging impairs autoregulatory protection in the brain, exacerbating hypertension-induced cerebromicrovascular injury, neuroinflammation, and development of vascular cognitive impairment. Despite the importance of the age-related decline in circulating insulin-like growth factor-1 (IGF-1) levels in cerebrovascular aging, the effects of IGF-1 deficiency on functional adaptation of cerebral arteries to high blood pressure remain elusive. To determine whether IGF-1 deficiency impairs autoregulatory protection, hypertension was induced in control and IGF-1-deficient mice (Igf1(f/f)+TBG-iCre-AAV8) by chronic infusion of angiotensin-II. In hypertensive control mice, cerebral blood flow (CBF) autoregulation was extended to higher pressure values and the pressure-induced tone of middle cerebral arteries (MCAs) was increased. In hypertensive IGF-1-deficient mice, autoregulation was markedly disrupted, and MCAs did not show adaptive increases in myogenic tone. In control mice, the mechanism of adaptation to hypertension involved upregulation of TRPC channels in MCAs and this mechanism was impaired in hypertensive IGF-1-deficient mice. Likely downstream consequences of cerebrovascular autoregulatory dysfunction in hypertensive IGF-1-deficient mice included exacerbated disruption of the blood-brain barrier and neuroinflammation (microglia activation and upregulation of proinflammatory cytokines and chemokines), which were associated with impaired hippocampal cognitive function. Collectively, IGF-1 deficiency impairs autoregulatory protection in the brain of hypertensive mice, potentially exacerbating cerebromicrovascular injury and neuroinflammation mimicking the aging phenotype.
Exercise-induced cognitive plasticity, implications for mild cognitive impairment and Alzheimer’s disease

Directory of Open Access Journals (Sweden)

Philip P. Foster

2011-05-01

Full Text Available Lifestyle factors such as intellectual stimulation, cognitive and social engagement, nutrition, and various types of exercise appear to reduce the risk for common age-associated disorders such as Alzheimer’s disease (AD and vascular dementia. In fact, many studies have suggested that promoting physical activity can have a protective effect against cognitive deterioration later in life. Slowing or a deterioration of walking speed is associated with a poor performance in tests assessing psychomotor speed and verbal fluency in elderly individuals. Fitness training influences a wide range of cognitive processes, and the largest positive impact observed is for executive (a.k.a. frontal lobe functions. Studies show that exercise improves additional cognitive functions such as tasks mediated by the hippocampus, and result in major changes in plasticity in the hippocampus. Interestingly, this exercise-induced plasticity is also pronounced in APOE ε4 carriers who express a risk factor for late-onset AD that may modulate the effect of treatments. Based on AD staging by Braak et al., we propose that the effects of exercise occur in two temporo-spatial continua of events. The inward continuum from isocortex (neocortex to entorhinal cortex/hippocampus for amyloidosis and a reciprocal outward continuum for neurofibrillary alterations. The exercise-induced hypertrophy of the hippocampus at the core of these continua is evaluated in terms of potential for prevention to stave off neuronal degeneration. Exercise-induced production of growth factors such as the brain-derived neurotrophic factor (BDNF has been shown to enhance neurogenesis and to play a key role in positive cognitive effects. Insulin-like growth factor (IGF-1 may mediate the exercise-induced response to exercise on BDNF, neurogenesis and cognitive performance. It is also postulated to regulate brain amyloid β (Aβ levels by increased clearance via the choroid plexus. Growth factors
Exercise-induced prostacyclin release positively correlates with VO(2max) in young healthy men.

Science.gov (United States)

Zoladz, J A; Majerczak, J; Duda, K; Chłopicki, S

2009-01-01

In this study we have evaluated the effect of maximal incremental cycling exercise (IE) on the systemic release of prostacyclin (PGI(2)), assessed as plasma 6-keto-PGF(1alpha) concentration in young healthy men. Eleven physically active - untrained men (mean +/- S.D.) aged 22.7 +/- 2.1 years; body mass 76.3 +/- 9.1 kg; BMI 23.30 +/- 2.18 kg . m(-2); maximal oxygen uptake (VO(2max)) 46.5 +/- 3.9 ml . kg(-1) . min(-1), performed an IE test until exhaustion. Plasma concentrations of 6-keto-PGF(1alpha), lactate, and cytokines were measured in venous blood samples taken prior to the exercise and at the exhaustion. The net exercise-induced increase in 6-keto-PGF(1alpha) concentration, expressed as the difference between the end-exercise minus pre-exercise concentration positively correlated with VO(2max) (r=0.78, p=0.004) as well as with the net VO(2) increase at exhaustion (r=0.81, p=0.003), but not with other respiratory, cardiac, metabolic or inflammatory parameters of the exercise (minute ventilation, heart rate, plasma lactate, IL-6 or TNF-alpha concentrations). The exercise-induced increase in 6-keto-PGF(1alpha) concentration?? was significantly higher (p=0.008) in a group of subjects (n=5) with the highest VO(2max) when compared to the group of subjects with the lowest VO(2max), in which no increase in 6-keto-PGF(1alpha) concentration was found. In conclusion, we demonstrated, to our knowledge for the first time, that exercise-induced release of PGI(2) in young healthy men correlates with VO(2max), suggesting that vascular capacity to release PGI(2) in response to physical exercise represents an important factor characterizing exercise tolerance. Moreover, we postulate that the impairment of exercise-induced release of PGI(2) leads to the increased cardiovascular hazard of vigorous exercise.
Physical exercise ameliorates mood disorder-like behavior on high fat diet-induced obesity in mice.

Science.gov (United States)

Park, Hye-Sang; Lee, Jae-Min; Cho, Han-Sam; Park, Sang-Seo; Kim, Tae-Woon

2017-04-01

Obesity is associated with mood disorders such as depression and anxiety. The aim of this study was to investigate whether treadmill exercise had any benefits on mood disorder by high fat diet (HFD) induced obesity. Mice were randomly divided into four groups: control, control and exercise, high fat diet (HFD), and HFD and exercise. Obesity was induced by a 20-week HFD (60%). In the exercise groups, exercise was performed 6 times a week for 12 weeks, with the exercise duration and intensity gradually increasing at 4-week intervals. Mice were tested in tail suspension and elevated plus maze tasks in order to verify the mood disorder like behavior such as depression and anxiety on obesity. In the present study, the number of 5-HT- and TPH-positive cells, and expression of 5-HT 1A and 5-HTT protein decreased in dorsal raphe, and depression and anxiety like behavior increased in HFD group compared with the CON group. In contrast, treadmill exercise ameliorated mood disorder like behavior by HFD induced obesity and enhanced expression of the serotonergic system in the dorsal raphe. We concluded that exercise increases the capacity of the serotonergic system in the dorsal raphe, which improves the mood disorders associated with HFD-induced obesity. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
Enrichment of skin-derived neural precursor cells from dermal cell populations by altering culture conditions.

Science.gov (United States)

Bayati, Vahid; Gazor, Rohoullah; Nejatbakhsh, Reza; Negad Dehbashi, Fereshteh

2016-01-01

As stem cells play a critical role in tissue repair, their manipulation for being applied in regenerative medicine is of great importance. Skin-derived precursors (SKPs) may be good candidates for use in cell-based therapy as the only neural stem cells which can be isolated from an accessible tissue, skin. Herein, we presented a simple protocol to enrich neural SKPs by monolayer adherent cultivation to prove the efficacy of this method. To enrich neural SKPs from dermal cell populations, we have found that a monolayer adherent cultivation helps to increase the numbers of neural precursor cells. Indeed, we have cultured dermal cells as monolayer under serum-supplemented (control) and serum-supplemented culture, followed by serum free cultivation (test) and compared. Finally, protein markers of SKPs were assessed and compared in both experimental groups and differentiation potential was evaluated in enriched culture. The cells of enriched culture concurrently expressed fibronectin, vimentin and nestin, an intermediate filament protein expressed in neural and skeletal muscle precursors as compared to control culture. In addition, they possessed a multipotential capacity to differentiate into neurogenic, glial, adipogenic, osteogenic and skeletal myogenic cell lineages. It was concluded that serum-free adherent culture reinforced by growth factors have been shown to be effective on proliferation of skin-derived neural precursor cells (skin-NPCs) and drive their selective and rapid expansion.
Treatment strategies for chemotherapy-induced peripheral neuropathy: potential role of exercise

Directory of Open Access Journals (Sweden)

Karen Y. Wonders

2011-12-01

Full Text Available Chemotherapy-induced peripheral neuropathy (CIPN is a common, dose-limiting effect of cancer therapy that often has negative implications on a patient’s quality of life. The pain associated with CIPN has long been recognized as one of the most difficult types of pain to treat. Historically, much effort has been made to explore pharmacological therapies aimed at reducing symptoms of CIPN. While many of these agents provide a modest relief in the symptoms of peripheral neuropathy, many have been shown to have additional negative side effects for cancer patients. Therefore, the authors suggest exercise rehabilitation as one lifestyle modification that may positively impact the lives of patients with CIPN. To our knowledge, there are currently no published clinical trials examining the role of exercise in preserving neurological function following chemotherapy. However, investigations using low-to-moderate intensity exercise as an intervention in patients with diabetic peripheral neuropathy and hereditary motor and sensory neuropathies have produced promising results. Given that cancer patients appear to tolerate exercise, it seems plausible that exercise rehabilitation could be used as an effective strategy to minimize CIPN-induced detriments to quality of life.

The walking-induced transient hack concept is valid & relies on a transient early-exercise hypoxemia.

Directory of Open Access Journals (Sweden)

Antoine Bruneau

Full Text Available Decreased arterial oxygen pressure obtained at peak exercise is strong evidence of walking-induced hypoxemia, assuming that the lower pressure occurs just before exercise is stopped. Using empirical predefined models and transcutaneous oximetry, we have shown that some patients reporting exercise intolerance show a minimal value at the onset of walking and a post-exercise overshoot. These changes are referred to as transcutaneous "walking-induced transient hacks".In 245 patients, walking-induced transcutaneous oxygen pressure changes in the chest were analyzed using observer-independent clustering techniques. Clustering classes were compared to the profile types previously proposed with the cross-correlation technique. The classifications of patients according to both approaches were compared using kappa statistics. In 10 patients showing a hack on transcutaneous oximetry, we analyzed the results of direct iterative arterial sampling recorded during a new walking treadmill test.Clustering analysis resulted in 4 classes that closely fit the 4 most frequently proposed empirical models (cross-correlation coefficients: 0.93 to 0.97. The kappa between the two classifications was 0.865. In 10 patients showing transcutaneous hacks, the minimal direct arterial oxygen pressure value occurred at exercise onset, and these patients exhibited a recovery overshoot reaching a maximum at two minutes of recovery, confirming the walking-induced transient hypoxemia.In patients reporting exercise intolerance, transcutaneous oximetry could help to detect walking-induced transient hypoxemia, while peak-exercise arterial oximetry might be normal.
Exercise-induced amenorrhea and bone health in the adolescent athlete.

Science.gov (United States)

Warren, Michelle P; Chua, Abigail T

2008-01-01

Female participation in high school athletics has increased 800% in the last 30 years. The problem of exercise-induced amenorrhea was initially thought to be analogous to hypoestrogenism, but recent studies suggest that nutritional issues underlie most of the pathophysiology and that the mechanism is different from that seen in the primary hypogonadal state. Exercise-induced amenorrhea can be an indicator of an energy drain, and the presence of the other components of the female athlete triad-bone density loss and eating disorders-must be determined as well. Addressing skeletal problems related to nutritional and hormonal deficiencies in this population is of very high priority.
Serum Proteases Potentiate BMP-Induced Cell Cycle Re-entry of Dedifferentiating Muscle Cells during Newt Limb Regeneration.

Science.gov (United States)

Wagner, Ines; Wang, Heng; Weissert, Philipp M; Straube, Werner L; Shevchenko, Anna; Gentzel, Marc; Brito, Goncalo; Tazaki, Akira; Oliveira, Catarina; Sugiura, Takuji; Shevchenko, Andrej; Simon, András; Drechsel, David N; Tanaka, Elly M

2017-03-27

Limb amputation in the newt induces myofibers to dedifferentiate and re-enter the cell cycle to generate proliferative myogenic precursors in the regeneration blastema. Here we show that bone morphogenetic proteins (BMPs) and mature BMPs that have been further cleaved by serum proteases induce cell cycle entry by dedifferentiating newt muscle cells. Protease-activated BMP4/7 heterodimers that are present in serum strongly induced myotube cell cycle re-entry with protease cleavage yielding a 30-fold potency increase of BMP4/7 compared with canonical BMP4/7. Inhibition of BMP signaling via muscle-specific dominant-negative receptor expression reduced cell cycle entry in vitro and in vivo. In vivo inhibition of serine protease activity depressed cell cycle re-entry, which in turn was rescued by cleaved-mimic BMP. This work identifies a mechanism of BMP activation that generates blastema cells from differentiated muscle. Copyright © 2017 Elsevier Inc. All rights reserved.
Interleukin-2 (rIL-2)-induced lymphokine-activated killer (LAK) cells and their precursors express the VGO1 antigen

International Nuclear Information System (INIS)

Denegri, J.F.; Peterson, J.; Tilley, P.

1989-01-01

Precursor and effector cells of recombinant interleukin-2 (r-IL-2)-induced lymphokine-activated killer (LAK) activity were investigated for their expression of VGO1. Peripheral blood lymphocytes (PBL) from normal donors were purified and separated in a FACS 420 into VGO1+- and VGO1- cell fractions before and after culture for 96 hr with 100 U/ml of r-IL-2. Their lytic activity against K 562 and Daudi cells was measured in a 51Cr release assay. The majority, if not all, of the LAK effector and precursor cells was VGO1+ lymphocytes. The expression of VGO1 by LAK precursor cells remained stable under the culture conditions used in our experiments. VGO1- lymphocytes cultured with r-IL-2 demonstrated neither LAK-induced activity nor expression of VGO1 antigen
EXERCISE-INDUCED PULMONARY HEMORRHAGE AFTER RUNNING A MARATHON

Science.gov (United States)

We report on a healthy 26-year-old male who had an exercise-induced pulmonary hemorrhage (EIPH) within 24 hours of running a marathon. There were no symptoms, abnormalities on exam, or radiographic infiltrates. He routinely participated in bronchoscopy research and the EIPH was e...
Adrenaline but not noradrenaline is a determinant of exercise-induced lipid mobilization in human subcutaneous adipose tissue

DEFF Research Database (Denmark)

Glisezinski, I. de; Larrouy, D.; Bajzova, M.

2009-01-01

The relative contribution of noradrenaline (norepinephrine) and adrenaline (epinephrine) in the control of lipid mobilization in subcutaneous adipose tissue (SCAT) during exercise was evaluated in men treated with a somatostatin analogue, octreotide. Eight lean and eight obese young men matched...... of octreotide suppressed plasma insulin and growth hormone levels at rest and during exercise. It blocked the exercise-induced increase in plasma adrenaline while that of noradrenaline was unchanged. Plasma natriuretic peptides (NPs) level was higher at rest and during exercise under octreotide infusion in lean...... individuals. In conclusion, blockade of beta-adrenergic receptors during exercise performed during infusion of octreotide (blocking the exercise-induced rise in adrenaline but not that of noradrenaline) does not alter the exercise-induced lipolysis. This suggests that adrenaline is the main adrenergic agent...
Precursor Ion Scan Mode-Based Strategy for Fast Screening of Polyether Ionophores by Copper-Induced Gas-Phase Radical Fragmentation Reactions.

Science.gov (United States)

Crevelin, Eduardo J; Possato, Bruna; Lopes, João L C; Lopes, Norberto P; Crotti, Antônio E M

2017-04-04

The potential of copper(II) to induce gas-phase fragmentation reactions in macrotetrolides, a class of polyether ionophores produced by Streptomyces species, was investigated by accurate-mass electrospray tandem mass spectrometry (ESI-MS/MS). Copper(II)/copper(I) transition directly induced production of diagnostic acylium ions with m/z 199, 185, 181, and 167 from α-cleavages of [macrotetrolides + Cu] 2+ . A UPLC-ESI-MS/MS methodology based on the precursor ion scan of these acylium ions was developed and successfully used to identify isodinactin (1), trinactin (2), and tetranactin (3) in a crude extract of Streptomyces sp. AMC 23 in the precursor ion scan mode. In addition, copper(II) was also used to induce radical fragmentation reactions in the carboxylic acid polyether ionophore nigericin. The resulting product ions with m/z 755 and 585 helped to identify nigericin in a crude extract of Streptomyces sp. Eucal-26 by means of precursor ion scan experiments, demonstrating that copper-induced fragmentation reactions can potentially identify different classes of polyether ionophores rapidly and selectively.
A general rehabilitation inpatient with exercise-induced vasculitis.

Science.gov (United States)

Cushman, Dan; Rydberg, Leslie

2013-10-01

While on our general inpatient rehabilitation floor, a 58-year-old man with no hematologic or dermatologic history developed an erythematous patch on his medial ankle that turned more purpuric, with a slight orange tint, and was associated with mild pruritus. The diagnosis of exercise-induced vasculitis was made after initially being mistaken for cellulitis. This common exanthem is often misdiagnosed. Due to its association with exercise, the physiatrist should be aware of its presence in both the inpatient and outpatient settings. Copyright © 2013 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Exercise Ameliorates High Fat Diet Induced Cardiac Dysfunction by Increasing Interleukin 10

Directory of Open Access Journals (Sweden)

Varun eKesherwani

2015-04-01

Full Text Available Increasing evidence suggests that a sedentary lifestyle and a high fat diet (HFD leads to cardiomyopathy. Moderate exercise ameliorates cardiac dysfunction, however underlying molecular mechanisms are poorly understood. Increased inflammation due to induction of pro-inflammatory cytokine such as tumor necrosis factor-alpha (TNF-α and attenuation of anti-inflammatory cytokine such as interleukin10 (IL-10 contributes to cardiac dysfunction in obese and diabetics. We hypothesized that exercise training ameliorates HFD- induced cardiac dysfunction by mitigating obesity and inflammation through upregulation of IL-10 and downregulation of TNF-α. To test this hypothesis, eight week old, female C57BL/6J mice were fed with HFD and exercised (swimming 1hr/day for 5 days/week for eight weeks. The four treatment groups: normal diet (ND, HFD, HFD + exercise (HFD + Ex and ND + Ex were analyzed for mean body weight, blood glucose level, TNF-α, IL-10, cardiac fibrosis by Masson Trichrome, and cardiac dysfunction by echocardiography. Mean body weights were increased in HFD but comparatively less in HFD + Ex. The level of TNF-α was elevated and IL-10 was downregulated in HFD but ameliorated in HFD + Ex. Cardiac fibrosis increased in HFD and was attenuated by exercise in the HFD + Ex group. The percentage ejection fraction and fractional shortening were decreased in HFD but comparatively increased in HFD + Ex. There was no difference between ND and ND + Ex for the above parameters except an increase in IL-10 level following exercise. Based on these results, we conclude that exercise mitigates HFD- induced cardiomyopathy by decreasing obesity, inducing IL-10, and reducing TNF-α in mice.
Suppression of exercise-induced angina by magnesium sulfate in patients with variant angina

International Nuclear Information System (INIS)

Kugiyama, K.; Yasue, H.; Okumura, K.

1988-01-01

The effects of intravenous magnesium on exercise-induced angina were examined in 15 patients with variant angina and in 13 patients with stable effort angina and were compared with those of placebo. Symptom-limited bicycle exercise and thallium-201 myocardial scintigraphy were performed after intravenous administration of 0.27 mmol/kg body weight of magnesium sulfate and after placebo on different days. In all patients, serum magnesium levels after administration of magnesium sulfate were about twofold higher than levels after placebo. Exercise-induced angina associated with transient ST segment elevation occurred in 11 patients with variant angina receiving placebo and in only 2 of these patients receiving magnesium (p less than 0.005). On the other hand, exercise-induced angina was not suppressed by magnesium in any patient with stable effort angina. In these patients there was no significant difference in exercise duration after administration of placebo versus after administration of magnesium. The size of the perfusion defect as measured by thallium-201 scintigraphy was significantly less in patients with variant angina receiving magnesium than that in those receiving placebo (p less than 0.001), whereas it was not significantly different in patients with stable effort angina receiving placebo versus magnesium. In conclusion, exercise-induced angina is suppressed by intravenous magnesium in patients with variant angina but not in patients with stable effort angina. This beneficial effect of magnesium in patients with variant angina is most likely due to improvement of regional myocardial blood flow by suppression of coronary artery spasm
Screening adolescent athletes for exercise-induced asthma.

Science.gov (United States)

Feinstein, R A; LaRussa, J; Wang-Dohlman, A; Bartolucci, A A

1996-04-01

To pilot test an exercise-induced asthma (EIA) screening program using a submaximal step-test and pulmonary function test (PFT) to identify athletes with EIA and to determine if a physical examination or self-reported history could be used to predict the existence of EIA. Screening and diagnostic testing using a convenience sample. Birmingham, Alabama, during athletic preparticipation examination (PPE). Fifty-two African-American, male football players aged 14-18 years being evaluated for participation in scholastic athletics. No athlete refused participation. Four were excluded because of need for further evaluation unrelated to any pulmonary condition. Each athlete completed a medical history, allergy history, physical examination, preexercise pulmonary function test (PFT), submaximal step-test, and a series of postexercise PFTs. Major outcome measurements were changes in forced expiration volume in 1s (FEV1) or peak expiratory flow rate (PEFR) after completing an exercise challenge. Seventeen of 48 athletes had a > or = 15% decrease in PEFR after exercise. Nine of 48 athletes had a > or = 15% decrease in FEV1 after exercise. The only self-reported item that differentiated subjects with normal and abnormal PFTs was a personal history of asthma (p < 0.05). Many athletes can be identified as having abnormal PFTs by use of a submaximal step-test as an exercise challenge. Self-reporting questionnaires and PPEs do not appear to be sensitive enough to identify athletes with this condition. If validated by future studies, this protocol could be used for the diagnosis of EIA.
Long-term treadmill exercise-induced neuroplasticity and associated memory recovery of streptozotocin-induced diabetic rats: an experimenter blind, randomized controlled study.

Science.gov (United States)

You, Joshua Sung H; Kim, Chung-Ju; Kim, Mee Young; Byun, Yong Gwon; Ha, So Young; Han, Bong Suk; Yoon, Bum Chul

2009-01-01

We investigated a long-term exercise-induced neuroplasticity and spatial memory recovery in 15 rats in a treadmill as follows: normal control rats (NC), streptozotocin (STZ)-induced diabetic control rats (DC), and STZ-induced diabetic rats exercising in a treadmill (DE). As per the DE group, the running exercise in a treadmill was administered for 30 minutes a day for 6 weeks. Neuronal immediate-early gene (IEG) expression (c-Fos) in the hippocampus and radial arm maze (RAM) tests were measured and revealed that the c-Fos levels in DE were significantly higher than those in NC and DC (p memory performance scores, obtained from the RAM test, were significantly different among the three groups (p memory scores of NC and DE were higher than those of DC (p memory. This is the first experimental evidence in literature that supports the efficacy of exercise-induced neuroplasticity and spatial motor memory in diabetes care.
Exercise-induced myokines in health and metabolic diseases

Directory of Open Access Journals (Sweden)

Byunghun So

2014-12-01

Full Text Available Skeletal muscle has been emerging as a research field since the past 2 decades. Contraction of a muscle, which acts as a secretory organ, stimulates production, secretion, and expression of cytokines or other muscle fiber-derived peptides, i.e., myokines. Exercise-induced myokines influence crosstalk between different organs in an autocrine, endocrine, or paracrine fashion. Myokines are recently recognized as potential candidates for treating metabolic diseases through their ability to stimulate AMP-activated protein kinase signaling, increase glucose uptake, and improve lipolysis. Myokines may have positive effects on metabolic disorders, type 2 diabetes, or obesity. Numerous studies on myokines suggested that myokines offer a potential treatment option for preventing metabolic diseases. This review summarizes the current understanding of the positive effects of exercise-induced myokines, such as interleukin-15, brain-derived neurotrophic factor, leukemia inhibitory factor, irisin, fibroblast growth factor 21, and secreted protein acidic and rich in cysteine, on metabolic diseases.
PGC-1α is dispensable for exercise-induced mitochondrial biogenesis in skeletal muscle.

Directory of Open Access Journals (Sweden)

Glenn C Rowe

Full Text Available Exercise confers numerous health benefits, many of which are thought to stem from exercise-induced mitochondrial biogenesis (EIMB in skeletal muscle. The transcriptional coactivator PGC-1α, a potent regulator of metabolism in numerous tissues, is widely believed to be required for EIMB. We show here that this is not the case. Mice engineered to lack PGC-1α specifically in skeletal muscle (Myo-PGC-1αKO mice retained intact EIMB. The exercise capacity of these mice was comparable to littermate controls. Induction of metabolic genes after 2 weeks of in-cage voluntary wheel running was intact. Electron microscopy revealed no gross abnormalities in mitochondria, and the mitochondrial biogenic response to endurance exercise was as robust in Myo-PGC-1αKO mice as in wildtype mice. The induction of enzymatic activity of the electron transport chain by exercise was likewise unperturbed in Myo-PGC-1αKO mice. These data demonstrate that PGC-1α is dispensable for exercise-induced mitochondrial biogenesis in skeletal muscle, in sharp contrast to the prevalent assumption in the field.
Exercise-induced muscle modifications

International Nuclear Information System (INIS)

Kerviler, E. de; Willig, A.L.; Jehenson, P.; Duboc, D.; Syrota, A.

1990-01-01

This paper compares changes in muscle proton T2 after exercise in normal subjects and in patients with muscular glycogenoses. Four patients suffering from muscular glycogenosis and eight normal volunteers were studied. Muscle T2s were measured in forearm muscles at rest and after exercise, with a 0.5-T imager. The exercise was performed with handgrips and was evaluated by P-31 spectroscopy (end-exercise decrease in pH and phosphocreatine) performed with a 2-T magnet. In normal subjects, a relative T2 increase, ranging from 14% to 44%, was observed in the exercised muscles. In the patients, who cannot produce lactate during exercise, weak pH variation occurred, and only a slight T2 increase (7% - 9%) was observed
Adapted physical exercise enhances activation and differentiation potential of satellite cells in the skeletal muscle of old mice.

Science.gov (United States)

Cisterna, Barbara; Giagnacovo, Marzia; Costanzo, Manuela; Fattoretti, Patrizia; Zancanaro, Carlo; Pellicciari, Carlo; Malatesta, Manuela

2016-05-01

During ageing, a progressive loss of skeletal muscle mass and a decrease in muscle strength and endurance take place, in the condition termed sarcopenia. The mechanisms of sarcopenia are complex and still unclear; however, it is known that muscle atrophy is associated with a decline in the number and/or efficiency of satellite cells, the main contributors to muscle regeneration. Physical exercise proved beneficial in sarcopenia; however, knowledge of the effect of adapted physical exercise on the myogenic properties of satellite cells in aged muscles is limited. In this study the amount and activation state of satellite cells as well as their proliferation and differentiation potential were assessed in situ by morphology, morphometry and immunocytochemistry at light and transmission electron microscopy on 28-month-old mice submitted to adapted aerobic physical exercise on a treadmill. Sedentary age-matched mice served as controls, and sedentary adult mice were used as a reference for an unperturbed control at an age when the capability of muscle regeneration is still high. The effect of physical exercise in aged muscles was further analysed by comparing the myogenic potential of satellite cells isolated from old running and old sedentary mice using an in vitro system that allows observation of the differentiation process under controlled experimental conditions. The results of this ex vivo and in vitro study demonstrated that adapted physical exercise increases the number and activation of satellite cells as well as their capability to differentiate into structurally and functionally correct myotubes (even though the age-related impairment in myotube formation is not fully reversed): this evidence further supports adapted physical exercise as a powerful, non-pharmacological approach to counteract sarcopenia and the age-related deterioration of satellite cell capabilities even at very advanced age. © 2016 Anatomical Society.
Glycopyrrolate abolishes the exercise-induced increase in cerebral perfusion in humans

DEFF Research Database (Denmark)

Seifert, Thomas; Fisher, James P; Young, Colin N

2010-01-01

Brain blood vessels contain muscarinic receptors that are important for cerebral blood flow (CBF) regulation, but whether a cholinergic receptor mechanism is involved in the exercise-induced increase in cerebral perfusion or affects cerebral metabolism remains unknown. We evaluated CBF and cerebral......(mean) during ergometer cycling (n = 8). Separate, randomized and counterbalanced trials were performed in control (no drug) conditions and following muscarinic cholinergic receptor blockade by glycopyrrolate. Glycopyrrolate increased resting heart rate from approximately 60 to approximately 110 beats min(-1...... abolished by glycopyrrolate (P important for the exercise-induced increase in cerebral perfusion without affecting the cerebral metabolic rate for oxygen....
Effects of Exercise on Cardiovascular Dysfunctions Induced by Cigarette Smoking

Directory of Open Access Journals (Sweden)

Abdel-Sater Khaled A.

2008-06-01

Full Text Available Smoking is known to adversely affect many organs and systems in human, where the cardiovascular system is one of the important targets. However, the exact mechanisms by which cigarette smoke alters myocardial and endothelial cells function and induces cardiovascular pathology are not clear. There are no reports especially with nitric oxide (NO•, uric acid and hemodynamics after acute exercise in smokers up to date. This study is designed to investigate the role of oxidative stress, NO• and uric acid in the pathophysiologic mechanisms of smoking- induced cardiovascular diseases.40 apparently healthy subjects were studied. Depending on their previous physical conditioning status subjects were divided into equal four groups (n=10, physically active nonsmokers, physically active smokers, sedentary nonsmokers and sedentary smokers. Exercise tolerance was evaluated for each subject by using a running race (3 kilometers after a worming up period of 5 minutes.The obtained data revealed that regular exercise significantly decreased the plasma malonaldehyde, total cholesterol, LDL and uric acid levels below sedentary levels. Pre and post race plasma level of malonaldehyde and uric acid levels were significantly increased, while, plasma glutathione and NO• were decreased in sedentary smokers than the sedentary non smokers, physically active smokers and physically active non smokers.These findings point to the role of NO•, uric acid and lipid peroxide in the pathophysiologic mechanisms of smoking induced cardiovascular diseases. Sedentary smokers may be at an even greater risk of oxidative stress-related cardiovascular diseases. Finally, every body should include in a regular exercise.
Endurance exercise modulates levodopa induced growth hormone release in patients with Parkinson's disease.

Science.gov (United States)

Müller, Thomas; Welnic, Jacub; Woitalla, Dirk; Muhlack, Siegfried

2007-07-11

Acute levodopa (LD) application and exercise release human growth hormone (GH). An earlier trial showed, that combined stimulus of exercise and LD administration is the best provocative test for GH response in healthy participants. Objective was to show this combined effect of LD application and exercise on GH response and to investigate the impact on LD metabolism in 20 previously treated patients with Parkinson's disease (PD). We measured GH- and LD plasma concentrations following soluble 200 mg LD/50 mg benserazide administration during endurance exercise and rest on two separate consecutive days. GH concentrations significantly increased on both days, but GH release was significantly delayed during rest. LD metabolism was not altered due to exercise in a clinical relevant manner. Exercise induced a significant faster LD stimulated GH release in comparison with the rest condition. We did not find the supposed increase of LD induced GH release by endurance exercise. We assume, that only a limited amount of GH is available for GH release in the anterior pituitary following an acute 200 mg LD administration. GH disposal also depends on growth hormone releasing hormone (GHRH), which is secreted into hypothalamic portal capillaries. During the exercise condition, the resulting higher blood pressure supports blood flow and thus GHRH transport towards the GH producing cells in the pituitary. This might additionally have caused the significant faster GH release during exercise.
Effect of antioxidant supplementation on exercise-induced cardiac troponin release in cyclists: a randomized trial.

Science.gov (United States)

Klinkenberg, Lieke J J; Res, Peter T; Haenen, Guido R; Bast, Aalt; van Loon, Luc J C; van Dieijen-Visser, Marja P; Meex, Steven J R

2013-01-01

Cardiac troponin is the biochemical gold standard to diagnose acute myocardial infarction. Interestingly however, elevated cardiac troponin concentrations are also frequently observed during and after endurance-type exercise. Oxidative stress associated with prolonged exercise has been proposed to contribute to cardiac troponin release. Therefore, the aim of this study was to assess the effect of 4 week astaxanthin supplementation (a potent cartenoid antioxidant) on antioxidant capacity and exercise-induced cardiac troponin release in cyclists. Thirty-two well-trained male cyclists (age 25±5, weight 73±7 kg, maximum O2 uptake 60±5 mL·kg(-1)·min(-1), Wmax 5.4±0.5 W·kg(-1); mean ± SD) were repeatedly subjected to a laboratory based standardized exercise protocol before and after 4 weeks of astaxanthin (20 mg/day), or placebo supplementation in a double-blind randomized manner. Blood samples were obtained at baseline, at 60 min of cycling and immediately post-exercise (≈ 120 min). The pre-supplementation cycling trial induced a significant rise of median cardiac troponin T concentrations from 3.2 (IQR 3.0-4.2) to 4.7 ng/L (IQR 3.7-6.7), immediately post-exercise (pexercise-induced cardiac troponin T release (p = 0.24), as measured by the incremental area under the curve. Furthermore, the elevation in basal plasma astaxanthin concentrations was not reflected in changes in antioxidant capacity markers (trolox equivalent antioxidant capacity, uric acid, and malondialdehyde). Markers of inflammation (high-sensitivity C-reactive protein) and exercise-induced skeletal muscle damage (creatine kinase) were equally unaffected by astaxanthin supplementation. Despite substantial increases in plasma astaxanthin concentrations, astaxanthin supplementation did not improve antioxidant capacity in well-trained cyclists. Accordingly, exercise-induced cardiac troponin T concentrations were not affected by astaxanthin supplementation. ClinicalTrials.gov NCT01241877.

Effect of nano- and micro-scale topological features on alignment of muscle cells and commitment of myogenic differentiation

International Nuclear Information System (INIS)

Jana, Soumen; Leung, Matthew; Zhang, Miqin; Chang, Julia

2014-01-01

Skeletal muscle injury can lead to severe motor deficits that adversely affect movement and quality of life. Current surgical treatments for skeletal muscle are hindered by the poor formation of organized myotube bundles at the wound site. Tissue-engineered skeletal muscle constructs to date have been unable to generate high degrees of myotube density and alignment. Generating a suitable in vitro tissue-engineered skeletal muscle construct requires the design of a scaffold that recapitulates the structural combination of nanoscale collagen fibrils and aligned microscale basal lamina tracks present in the native extracellular matrix (ECM). We hypothesized that a 3D aligned tubular porous scaffold containing aligned nanofibers inside the pores can mimic the native muscle tissue environment. We constructed a laminar section of the hypothesized scaffold with aligned chitosan-PCL nanofibers arranged co-axially with the aligned microscale chitosan scaffold bands to mimic the required myogenic environment. A 6-day study of C2C12 mouse myoblast cells cultured on this hybrid scaffold indicated that the nanofibers and scaffold bands in the scaffold played a synergetic role in directing cell orientation, interaction, migration and organization. Our results showed that aligned nanofibers mediated cell alignment and the aligned scaffold bands induced the formation of a more compact assembly of myotube cells as compared to various control substrates including chitosan films, nanofibers, and chitosan bands. The expression levels of both early and late-stage myogenic differentiation genes associated with myogenin and myosin heavy chain, respectively, were higher on the hybrid substrate than on control substrates. Our study suggests that the combination of nano and microscale topological features in the ECM can direct myogenic differentiation, and the hybrid material has the potential to improve the outcome of skeletal tissue engineering. (papers)
Combined ocular and cervical vestibular evoked myogenic potential in individuals with vestibular hyporeflexia and in patients with Ménière's disease.

Science.gov (United States)

Silva, Tatiana Rocha; de Resende, Luciana Macedo; Santos, Marco Aurélio Rocha

The vestibular evoked myogenic potential is a potential of mean latency that measures the muscle response to auditory stimulation. This potential can be generated from the contraction of the sternocleidomastoid muscle and also from the contraction of extraocular muscles in response to high-intensity sounds. This study presents a combined or simultaneous technique of cervical and ocular vestibular evoked myogenic potential in individuals with changes in the vestibular system, for use in otoneurologic diagnosis. To characterize the records and analyze the results of combined cervical and ocular VEMP in individuals with vestibular hyporeflexia and in those with Ménière's disease. The study included 120 subjects: 30 subjects with vestibular hyporeflexia, 30 with Ménière's disease, and 60 individuals with normal hearing. Data collection was performed by simultaneously recording the cervical and ocular vestibular evoked myogenic potential. There were differences between the study groups (individuals with vestibular hyporeflexia and individuals with Ménière's disease) and the control group for most of wave parameters in combined cervical and ocular vestibular evoked myogenic potential. For cervical vestibular evoked myogenic potential, it was observed that the prolongation of latency of the P13 and N23 waves was the most frequent finding in the group with vestibular hyporeflexia and in the group with Ménière's disease. For ocular vestibular evoked myogenic potential, prolonged latency of N10 and P15 waves was the most frequent finding in the study groups. Combined cervical and ocular vestibular evoked myogenic potential presented relevant results for individuals with vestibular hyporeflexia and for those with Ménière's disease. There were differences between the study groups and the control group for most of the wave parameters in combined cervical and ocular vestibular evoked myogenic potential. Copyright © 2016 Associação Brasileira de Otorrinolaringologia
Dynamic Aerobic Exercise Induces Baroreflex Improvement in Diabetic Rats

Directory of Open Access Journals (Sweden)

Luciana Jorge

2012-01-01

Full Text Available The objective of the present study was to investigate the effects of an acute aerobic exercise on arterial pressure (AP, heart rate (HR, and baroreflex sensitivity (BRS in STZ-induced diabetic rats. Male Wistar rats were divided into control (n=8 and diabetic (n=8 groups. AP, HR, and BRS, which were measured by tachycardic and bradycardic (BR responses to AP changes, were evaluated at rest (R and postexercise session (PE on a treadmill. At rest, STZ diabetes induced AP and HR reductions, associated with BR impairment. Attenuation in resting diabetes-induced AP (R: 103±2 versus PE: 111±3 mmHg and HR (R: 290±7 versus PE: 328±10 bpm reductions and BR dysfunction (R: -0.70±0.06 versus PE: -1.21±0.09 bpm/mmHg was observed in the postexercise period. In conclusion, the hemodynamic and arterial baro-mediated control of circulation improvement in the postexercise period reinforces the role of exercise in the management of cardiovascular risk in diabetes.
Dynamic Aerobic Exercise Induces Baroreflex Improvement in Diabetic Rats

Science.gov (United States)

Jorge, Luciana; da Pureza, Demilto Y.; Dias, Danielle da Silva; Conti, Filipe Fernandes; Irigoyen, Maria-Cláudia; De Angelis, Kátia

2012-01-01

The objective of the present study was to investigate the effects of an acute aerobic exercise on arterial pressure (AP), heart rate (HR), and baroreflex sensitivity (BRS) in STZ-induced diabetic rats. Male Wistar rats were divided into control (n = 8) and diabetic (n = 8) groups. AP, HR, and BRS, which were measured by tachycardic and bradycardic (BR) responses to AP changes, were evaluated at rest (R) and postexercise session (PE) on a treadmill. At rest, STZ diabetes induced AP and HR reductions, associated with BR impairment. Attenuation in resting diabetes-induced AP (R: 103 ± 2 versus PE: 111 ± 3 mmHg) and HR (R: 290 ± 7 versus PE: 328 ± 10 bpm) reductions and BR dysfunction (R: −0.70 ± 0.06 versus PE: −1.21 ± 0.09 bpm/mmHg) was observed in the postexercise period. In conclusion, the hemodynamic and arterial baro-mediated control of circulation improvement in the postexercise period reinforces the role of exercise in the management of cardiovascular risk in diabetes. PMID:22203833
Autophagy is induced by resistance exercise in young men but unfolded protein response is induced regardless of age.

Science.gov (United States)

Hentilä, Jaakko; Ahtiainen, Juha P; Paulsen, Gøran; Raastad, Truls; Häkkinen, Keijo; Mero, Antti A; Hulmi, Juha J

2018-04-02

Autophagy and unfolded protein response (UPR) appear to be important for skeletal muscle homeostasis and may be altered by exercise. Our aim was to investigate the effects of resistance exercise and training on indicators of UPR and autophagy in healthy untrained young men (n = 12, 27 ± 4 years) and older men (n = 8, 61 ± 6 years) as well as in resistance-trained individuals (n = 15, 25 ± 5 years). Indicators of autophagy and UPR were investigated from the muscle biopsies after a single resistance exercise bout and after 21 weeks of resistance training. Lipidated LC3II as an indicator of autophagosome content increased at 48 hours post resistance exercise (P resistance-training period (P resistance exercise in untrained young and older men (P resistance-training period regardless of age. UPR was unchanged within the first few hours after the resistance exercise bout regardless of the training status. Changes in autophagy and UPR ER indicators did not correlate with a resistance-training-induced increase in muscle strength and size. Autophagosome content is increased by resistance training in young previously untrained men, but this response may be blunted by aging. However, unfolded protein response is induced by an unaccustomed resistance exercise bout in a delayed manner regardless of age. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Taurine supplementation attenuates delayed increase in exercise-induced arterial stiffness.

Science.gov (United States)

Ra, Song-Gyu; Choi, Youngju; Akazawa, Nobuhiko; Ohmori, Hajime; Maeda, Seiji

2016-06-01

There is a delayed increase in arterial stiffness after eccentric exercise that is possibly mediated by the concurrent delayed increase in circulating oxidative stress. Taurine has anti-oxidant action, and taurine supplementation may be able to attenuate the increase in oxidative stress after exercise. The purpose of the present study was to investigate whether taurine supplementation attenuates the delayed increase in arterial stiffness after eccentric exercise. In the present double-blind, randomized, and placebo-controlled trial, we divided 29 young, healthy men into 2 groups. Subjects received either 2.0 g of placebo (n = 14) or taurine (n = 15) 3 times per day for 14 days prior to the exercise, on the day of exercise, and the following 3 days. The exercise consisted of 2 sets of 20 maximal-effort eccentric repetitions with the nondominant arm only. On the morning of exercise and for 4 days thereafter, we measured serum malondialdehyde (MDA) and carotid-femoral pulse wave velocity (cfPWV) as indices of oxidative stress and arterial stiffness, respectively. On the third and fourth days after exercise, both MDA and cfPWV significantly increased in the placebo group. However, these elevations were significantly attenuated in the taurine group. The increase in MDA was associated with an increase in cfPWV from before exercise to 4 days after exercise (r = 0.597, p taurine group. Our results suggest that delayed increase in arterial stiffness after eccentric exercise was probably affected by the exercise-induced oxidative stress and was attenuated by the taurine supplementation.
Effect of antioxidant supplementation on exercise-induced cardiac troponin release in cyclists: a randomized trial.

Directory of Open Access Journals (Sweden)

Lieke J J Klinkenberg

Full Text Available Cardiac troponin is the biochemical gold standard to diagnose acute myocardial infarction. Interestingly however, elevated cardiac troponin concentrations are also frequently observed during and after endurance-type exercise. Oxidative stress associated with prolonged exercise has been proposed to contribute to cardiac troponin release. Therefore, the aim of this study was to assess the effect of 4 week astaxanthin supplementation (a potent cartenoid antioxidant on antioxidant capacity and exercise-induced cardiac troponin release in cyclists.Thirty-two well-trained male cyclists (age 25±5, weight 73±7 kg, maximum O2 uptake 60±5 mL·kg(-1·min(-1, Wmax 5.4±0.5 W·kg(-1; mean ± SD were repeatedly subjected to a laboratory based standardized exercise protocol before and after 4 weeks of astaxanthin (20 mg/day, or placebo supplementation in a double-blind randomized manner. Blood samples were obtained at baseline, at 60 min of cycling and immediately post-exercise (≈ 120 min.The pre-supplementation cycling trial induced a significant rise of median cardiac troponin T concentrations from 3.2 (IQR 3.0-4.2 to 4.7 ng/L (IQR 3.7-6.7, immediately post-exercise (p<0.001. Four weeks of astaxanthin supplementation significantly increased mean basal plasma astaxanthin concentrations from non-detectable values to 175±86 µg·kg(-1. However, daily astaxanthin supplementation had no effect on exercise-induced cardiac troponin T release (p = 0.24, as measured by the incremental area under the curve. Furthermore, the elevation in basal plasma astaxanthin concentrations was not reflected in changes in antioxidant capacity markers (trolox equivalent antioxidant capacity, uric acid, and malondialdehyde. Markers of inflammation (high-sensitivity C-reactive protein and exercise-induced skeletal muscle damage (creatine kinase were equally unaffected by astaxanthin supplementation.Despite substantial increases in plasma astaxanthin concentrations
Protective effects of physical exercise on MDMA-induced cognitive and mitochondrial impairment.

Science.gov (United States)

Taghizadeh, Ghorban; Pourahmad, Jalal; Mehdizadeh, Hajar; Foroumadi, Alireza; Torkaman-Boutorabi, Anahita; Hassani, Shokoufeh; Naserzadeh, Parvaneh; Shariatmadari, Reyhaneh; Gholami, Mahdi; Rouini, Mohammad Reza; Sharifzadeh, Mohammad

2016-10-01

Debate continues about the effect of 3, 4-methylenedioxymethamphetamine (MDMA) on cognitive and mitochondrial function through the CNS. It has been shown that physical exercise has an important protective effect on cellular damage and death. Therefore, we investigated the effect of physical exercise on MDMA-induced impairments of spatial learning and memory as well as MDMA effects on brain mitochondrial function in rats. Male wistar rats underwent short-term (2 weeks) or long-term (4 weeks) treadmill exercise. After completion of exercise duration, acquisition and retention of spatial memory were evaluated by Morris water maze (MWM) test. Rats were intraperitoneally (I.P) injected with MDMA (5, 10, and 15mg/kg) 30min before the first training trial in 4 training days of MWM. Different parameters of brain mitochondrial function were measured including the level of ROS production, mitochondrial membrane potential (MMP), mitochondrial swelling, mitochondrial outermembrane damage, the amount of cytochrome c release from the mitochondria, and ADP/ATP ratio. MDMA damaged the spatial learning and memory in a dose-dependent manner. Brain mitochondria isolated from the rats treated with MDMA showed significant increase in ROS formation, collapse of MMP, mitochondrial swelling, and outer membrane damage, cytochrome c release from the mitochondria, and finally increased ADP/ATP ratio. This study also found that physical exercise significantly decreased the MDMA-induced impairments of spatial learning and memory and also mitochondrial dysfunction. The results indicated that MDMA-induced neurotoxicity leads to brain mitochondrial dysfunction and subsequent oxidative stress is followed by cognitive impairments. However, physical exercise could reduce these deleterious effects of MDMA through protective effects on brain mitochondrial function. Copyright © 2016 Elsevier Inc. All rights reserved.
Cyclooxygenase inhibitors and the exercise-induced stress response

African Journals Online (AJOL)

steroidal anti-inflammatory drug (NSAID) naproxen, and of the coxib, rofecoxib, on the exercise-induced stress response. Design. Eight subjects (age 20.9 ± 1.1 years, weight 70.4 ± 3.9 kg, height 170.9 ± 6.7 cm, body surface area 1.82 ± 0.09 m2, ...
Pharmacological targeting of the ephrin receptor kinase signalling by GLPG1790 in vitro and in vivo reverts oncophenotype, induces myogenic differentiation and radiosensitizes embryonal rhabdomyosarcoma cells

Directory of Open Access Journals (Sweden)

Francesca Megiorni

2017-10-01

Full Text Available Abstract Background EPH (erythropoietin-producing hepatocellular receptors are clinically relevant targets in several malignancies. This report describes the effects of GLPG1790, a new potent pan-EPH inhibitor, in human embryonal rhabdomyosarcoma (ERMS cell lines. Methods EPH-A2 and Ephrin-A1 mRNA expression was quantified by real-time PCR in 14 ERMS tumour samples and in normal skeletal muscle (NSM. GLPG1790 effects were tested in RD and TE671 cell lines, two in vitro models of ERMS, by performing flow cytometry analysis, Western blotting and immunofluorescence experiments. RNA interfering experiments were performed to assess the role of specific EPH receptors. Radiations were delivered using an x-6 MV photon linear accelerator. GLPG1790 (30 mg/kg in vivo activity alone or in combination with irradiation (2 Gy was determined in murine xenografts. Results Our study showed, for the first time, a significant upregulation of EPH-A2 receptor and Ephrin-A1 ligand in ERMS primary biopsies in comparison to NSM. GLPG1790 in vitro induced G1-growth arrest as demonstrated by Rb, Cyclin A and Cyclin B1 decrease, as well as by p21 and p27 increment. GLPG1790 reduced migratory capacity and clonogenic potential of ERMS cells, prevented rhabdosphere formation and downregulated CD133, CXCR4 and Nanog stem cell markers. Drug treatment committed ERMS cells towards skeletal muscle differentiation by inducing a myogenic-like phenotype and increasing MYOD1, Myogenin and MyHC levels. Furthermore, GLPG1790 significantly radiosensitized ERMS cells by impairing the DNA double-strand break repair pathway. Silencing of both EPH-A2 and EPH-B2, two receptors preferentially targeted by GLPG1790, closely matched the effects of the EPH pharmacological inhibition. GLPG1790 and radiation combined treatments reduced tumour mass by 83% in mouse TE671 xenografts. Conclusions Taken together, our data suggest that altered EPH signalling plays a key role in ERMS development and that
Exercise training starting at weaning age preserves cardiac pacemaker function in adulthood of diet-induced obese rats.

Science.gov (United States)

Carvalho de Lima, Daniel; Guimarães, Juliana Bohnen; Rodovalho, Gisele Vieira; Silveira, Simonton Andrade; Haibara, Andrea Siqueira; Coimbra, Cândido Celso

2014-08-01

Peripheral sympathetic overdrive in young obese subjects contributes to further aggravation of insulin resistance, diabetes, and hypertension, thus inducing worsening clinical conditions in adulthood. Exercise training has been considered a strategy to repair obesity autonomic dysfunction, thereby reducing the cardiometabolic risk. Therefore, the aim of this study was to assess the effect of early exercise training, starting immediately after weaning, on cardiac autonomic control in diet-induced obese rats. Male Wistar rats (weaning) were divided into four groups: (i) a control group (n = 6); (ii) an exercise-trained control group (n = 6); (iii) a diet-induced obesity group (n = 6); and (iv) an exercise-trained diet-induced obesity group (n = 6). The development of obesity was induced by 9 weeks of palatable diet intake, and the training program was implemented in a motor-driven treadmill (5 times per week) during the same period. After this period, animals were submitted to vein and artery catheter implantation to assess cardiac autonomic balance by methylatropine (3 mg/kg) and propranolol (4 mg/kg) administration. Exercise training increased running performance in both groups (p Exercise training also prevented the increased resting heart rate in obese rats, which seemed to be related to cardiac pacemaker activity preservation (p exercise program beginning at weaning age prevents cardiovascular dysfunction in obese rats, indicating that exercise training may be used as a nonpharmacological therapeutic strategy for the treatment of cardiometabolic diseases.
Endurance exercise-induced changes in BNP concentrations in cardiovascular patients versus healthy controls

NARCIS (Netherlands)

Aengevaeren, V.L.; Hopman, M.T.E.; Thijssen, D.H.J.; Kimmenade, R.R.J. van; Boer, M.J. de; Eijsvogels, T.M.H.

2017-01-01

BACKGROUND: Healthy athletes demonstrated increased B-type natriuretic peptide (BNP) concentrations following exercise, but it is unknown whether these responses are exaggerated in individuals with cardiovascular risk factors (CVRF) or disease (CVD). We compared exercise-induced increases in BNP
MAPK signaling pathways and HDAC3 activity are disrupted during differentiation of emerin-null myogenic progenitor cells

Directory of Open Access Journals (Sweden)

Carol M. Collins

2017-04-01

Full Text Available Mutations in the gene encoding emerin cause Emery–Dreifuss muscular dystrophy (EDMD. Emerin is an integral inner nuclear membrane protein and a component of the nuclear lamina. EDMD is characterized by skeletal muscle wasting, cardiac conduction defects and tendon contractures. The failure to regenerate skeletal muscle is predicted to contribute to the skeletal muscle pathology of EDMD. We hypothesize that muscle regeneration defects are caused by impaired muscle stem cell differentiation. Myogenic progenitors derived from emerin-null mice were used to confirm their impaired differentiation and analyze selected myogenic molecular pathways. Emerin-null progenitors were delayed in their cell cycle exit, had decreased myosin heavy chain (MyHC expression and formed fewer myotubes. Emerin binds to and activates histone deacetylase 3 (HDAC3. Here, we show that theophylline, an HDAC3-specific activator, improved myotube formation in emerin-null cells. Addition of the HDAC3-specific inhibitor RGFP966 blocked myotube formation and MyHC expression in wild-type and emerin-null myogenic progenitors, but did not affect cell cycle exit. Downregulation of emerin was previously shown to affect the p38 MAPK and ERK/MAPK pathways in C2C12 myoblast differentiation. Using a pure population of myogenic progenitors completely lacking emerin expression, we show that these pathways are also disrupted. ERK inhibition improved MyHC expression in emerin-null cells, but failed to rescue myotube formation or cell cycle exit. Inhibition of p38 MAPK prevented differentiation in both wild-type and emerin-null progenitors. These results show that each of these molecular pathways specifically regulates a particular stage of myogenic differentiation in an emerin-dependent manner. Thus, pharmacological targeting of multiple pathways acting at specific differentiation stages may be a better therapeutic approach in the future to rescue muscle regeneration in vivo.
Diagnostic value of exercise induced 18F-FDG myocardial metabolism scintigraphy in myocardial ischemia

International Nuclear Information System (INIS)

Shen Rui; He Zuoxiang; Shi Rongfang; Liu Xiujie; Tian Yueqin; Guo Feng; Wei Hongxing; Wu Yongjian; Qin Xuewen; Gao Runlin

2006-01-01

Objective: To evaluate the feasibility and diagnostic accuracy of exercise induced myocardial imaging with 18 F-fluorodeoxyglucose (FDG) in myocardial ischemia. Methods: Twenty-six patients with known or suspected coronary artery, disease (CAD) and with no prior myocardial infarction underwent simultaneous myocardial perfusion and metabolism imaging following intravenous injection of 99 Tc m -methoxy-isobutylisonitrile ( 99 Tc m -sestamibi) and 18 F-FDG at peak exercise. Subsequently rest perfusion imaging and coronary angiography (CAG) were performed in all patients. Exercise 18 F-FDG myocardial imaging was compared with 99 Tc m -sestamibi imaging and CAG. Results: In 22 patients with ≥50% narrowing over l coronary artery, 18 had perfusion abnormalities (sensitivity 82%), whereas 20 had abnormal myocardial 18 F-FDG uptake (sensitivity 91%, P>0.05). Patients with reversible (12 cases) or partial reversible (3 cases) perfusion abnormalities had increased myocardial 18 F-FDG uptake in abnormal perfusion segments. Compared with CAG, perfusion defect was seen in myocardial segments corresponding to 25 vascular territories of 51 vessels with ≥50% narrowing in 22 patients in 99 Tc m -sestamibi imaging (sensitivity 49%), whereas increased 18 F-FDG uptake was seen in 34 vascular territories (sensitivity 67%, P=0.008). Conclusions: Exercise induced myocardial ischemia can be imaged directly with 18 F-FDG. Combined exercise 18 F-FDG and 99 Tc m -sestamibi imaging provides a better assessment of exercise-induced myocardial ischemia as compared with exercise-rest perfusion imaging. (authors)
The impact of exercise-induced bronchoconstriction on athletic performance

DEFF Research Database (Denmark)

Price, Oliver J; Hull, James H; Backer, Vibeke

2014-01-01

BACKGROUND: Exercise-induced bronchoconstriction (EIB) describes the phenomenon of transient airway narrowing in association with physical activity. Although it may seem likely that EIB would have a detrimental impact on athletic performance, this has yet to be established. OBJECTIVES: The aim of...
Smad1/5/8 are myogenic regulators of murine and human mesoangioblasts

NARCIS (Netherlands)

Costamagna, D. (Domiziana); Quattrocelli, M. (Mattia); F.H.J. van Tienen; L. Umans (Lieve); De Coo, I.F.M. (Irineus F.M.); A. Zwijsen (An); D. Huylebroeck (Danny); Sampaolesi, M. (Maurilio)

2016-01-01

textabstractMesoangioblasts (MABs) are vessel-associated stem cells that express pericyte marker genes and participate in skeletal muscle regeneration. Molecular circuits that regulate the myogenic commitment of MABs are still poorly characterized. The critical role of bone morphogenetic protein
Immune-regulating effects of exercise on cigarette smoke-induced inflammation

Science.gov (United States)

Madani, Ashkan; Alack, Katharina; Richter, Manuel Jonas; Krüger, Karsten

2018-01-01

Long-term cigarette smoking (LTCS) represents an important risk factor for cardiac infarction and stroke and the central risk factor for the development of a bronchial carcinoma, smoking-associated interstitial lung fibrosis, and chronic obstructive pulmonary disease. The pathophysiologic development of these diseases is suggested to be promoted by chronic and progressive inflammation. Cigarette smoking induces repetitive inflammatory insults followed by a chronic and progressive activation of the immune system. In the pulmonary system of cigarette smokers, oxidative stress, cellular damage, and a chronic activation of pattern recognition receptors are described which are followed by the translocation of the NF-kB, the release of pro-inflammatory cytokines, chemokines, matrix metalloproteases, and damage-associated molecular patterns. In parallel, smoke pollutants cross directly through the alveolus–capillary interface and spread through the systemic bloodstream targeting different organs. Consequently, LTCS induces a systemic low-grade inflammation and increased oxidative stress in the vascular system. In blood, these processes promote an increased coagulation and endothelial dysfunction. In muscle tissue, inflammatory processes activate catabolic signaling pathways followed by muscle wasting and sarcopenia. In brain, several characteristics of neuroinflammation were described. Regular exercise training has been shown to be an effective nonpharmacological treatment strategy in smoke-induced pulmonary diseases. It is well established that exercise training exerts immune-regulating effects by activating anti-inflammatory signaling pathways. In this regard, the release of myokines from contracting skeletal muscle, the elevations of cortisol and adrenalin, the reduced expression of Toll-like receptors, and the increased mobilization of immune-regulating leukocyte subtypes might be of vital importance. Exercise training also increases the local and systemic
Exhaled nitric oxide predicts exercise-induced bronchoconstriction in asthmatic school children

DEFF Research Database (Denmark)

Buchvald, Frederik; Hermansen, Mette N; Nielsen, Kim G

2005-01-01

BACKGROUND: Exercise-induced bronchoconstriction (EIB) is of particular importance in children with asthma. It is an important measure of asthma control and should be monitored by exercise testing. However, exercise testing puts a large demand on health-care resources and is therefore not widely...... used in routine monitoring of pediatric asthma control. The fractional concentration of exhaled nitric oxide (FeNO) also reflects uncontrolled asthma. We hypothesized that FeNO may be used for prescreening of asthmatic children to exclude those with good asthma control unlikely to have EIB, thereby...... reducing the need for exercise testing. OBJECTIVE: The aim of this study was to estimate the value of FeNO as a predictor of EIB in asthmatic children. METHODS: Stable outpatient asthmatic school children performed standard exercise challenge tests and measurement of FeNO. RESULTS: FeNO and response...
Similarities between exercise-induced hypoalgesia and conditioned pain modulation in humans

DEFF Research Database (Denmark)

Vægter, Henrik Bjarke; Handberg, Gitte; Graven-Nielsen, Thomas

2014-01-01

Pain inhibitory mechanisms are often assessed by paradigms of exercise-induced hypoalgesia (EIH) and conditioned pain modulation (CPM). In this study it was hypothesised that the spatial and temporal manifestations of EIH and CPM were comparable. Eighty healthy subjects (40 females), between 18......-65 years participated in this randomized repeated-measures crossover trial with data collection on two different days. CPM was assessed by two different cold pressor tests (hand,foot). EIH was assessed through two intensities of aerobic bicycling exercises and two intensities of isometric muscle...... tests and after all of the exercise conditions, except low intensity bicycling. EIH after bicycling was increased in women compared to men. CPM and the EIH response after isometric exercises were comparable in men and women and not affected by age. The EIH response was larger in the exercising body part...
Efficient direct conversion of human fibroblasts into myogenic lineage induced by co-transduction with MYCL and MYOD1.

Science.gov (United States)

Wakao, Junko; Kishida, Tsunao; Fumino, Shigehisa; Kimura, Koseki; Yamamoto, Kenta; Kotani, Shin-Ichiro; Mizushima, Katsura; Naito, Yuji; Yoshikawa, Toshikazu; Tajiri, Tatsuro; Mazda, Osam

2017-06-24

The skeletal muscle consists of contractile myofibers and plays essential roles for maintenance of body posture, movement, and metabolic regulation. During the development and regeneration of the skeletal muscle tissue, the myoblasts fuse into multinucleated myotubes that subsequently form myofibers. Transplantation of myoblasts may make possible a novel regenerative therapy against defects or dysfunction of the skeletal muscle. It is reported that rodent fibroblasts are converted into myoblast-like cells and fuse to form syncytium after forced expression of exogenous myogenic differentiation 1 (MYOD1) that is a key transcription factor for myoblast differentiation. But human fibroblasts are less efficiently converted into myoblasts and rarely fused by MYOD1 alone. Here we found that transduction of v-myc avian myelocytomatosis viral oncogene lung carcinoma derived homolog (MYCL) gene in combination with MYOD1 gene induced myoblast-like phenotypes in human fibroblasts more strongly than MYOD1 gene alone. The rate of conversion was approximately 90%. The directly converted myoblasts (dMBs) underwent fusion in an ERK5 pathway-dependent manner. The dMBs also formed myofiber-like structure in vivo after an inoculation into mice at the subcutaneous tissue. The present results strongly suggest that the combination of MYCL plus MYOD1 may promote direct conversion of human fibroblasts into functional myoblasts that could potentially be used for regenerative therapy for muscle diseases and congenital muscle defects. Copyright © 2017 Elsevier Inc. All rights reserved.

Rejuvenation of MPTP-induced human neural precursor cell senescence by activating autophagy

Energy Technology Data Exchange (ETDEWEB)

Zhu, Liang [East Hospital, Tongji University School of Medicine, Shanghai (China); Dong, Chuanming [East Hospital, Tongji University School of Medicine, Shanghai (China); Department of Anatomy and Neurobiology, The Jiangsu Key Laboratory of Neuroregeneration, Nantong University, Nantong (China); Sun, Chenxi; Ma, Rongjie; Yang, Danjing [East Hospital, Tongji University School of Medicine, Shanghai (China); Zhu, Hongwen, E-mail: hongwen_zhu@hotmail.com [Tianjin Hospital, Tianjin Academy of Integrative Medicine, Tianjin (China); Xu, Jun, E-mail: xunymc2000@yahoo.com [East Hospital, Tongji University School of Medicine, Shanghai (China)

2015-08-21

Aging of neural stem cell, which can affect brain homeostasis, may be caused by many cellular mechanisms. Autophagy dysfunction was found in aged and neurodegenerative brains. However, little is known about the relationship between autophagy and human neural stem cell (hNSC) aging. The present study used 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) to treat neural precursor cells (NPCs) derived from human embryonic stem cell (hESC) line H9 and investigate related molecular mechanisms involved in this process. MPTP-treated NPCs were found to undergo premature senescence [determined by increased senescence-associated-β-galactosidase (SA-β-gal) activity, elevated intracellular reactive oxygen species level, and decreased proliferation] and were associated with impaired autophagy. Additionally, the cellular senescence phenotypes were manifested at the molecular level by a significant increase in p21 and p53 expression, a decrease in SOD2 expression, and a decrease in expression of some key autophagy-related genes such as Atg5, Atg7, Atg12, and Beclin 1. Furthermore, we found that the senescence-like phenotype of MPTP-treated hNPCs was rejuvenated through treatment with a well-known autophagy enhancer rapamycin, which was blocked by suppression of essential autophagy gene Beclin 1. Taken together, these findings reveal the critical role of autophagy in the process of hNSC aging, and this process can be reversed by activating autophagy. - Highlights: • We successfully establish hESC-derived neural precursor cells. • MPTP treatment induced senescence-like state in hESC-derived NPCs. • MPTP treatment induced impaired autophagy of hESC-derived NPCs. • MPTP-induced hESC-derived NPC senescence was rejuvenated by activating autophagy.
Hepatoprotective Effects of Swimming Exercise against D-Galactose-Induced Senescence Rat Model

Directory of Open Access Journals (Sweden)

Chi-Chang Huang

2013-01-01

Full Text Available This study investigates whether a 12-week swimming exercise training can prevent liver damage or senescence associated biomarkers in an experimental aging model in rats. Twenty-three male Sprague-Dawley rats were divided into four groups: vehicle treatment with sedentary control (C, , aging induction with sedentary (A, , vehicle treatment with swimming exercise (SW, , and aging induction with swimming exercise (A + SW, . Rats in groups A and AS received intraperitoneal D-galactose injections (150 mg/kg/day for 12 weeks to induce aging. Rats in groups SW and A + SW were subjected to swimming exercise training for 12 weeks. Body weight, liver weight, epididymal fat mass, blood biochemistry, and liver pathology were performed at the end of the experiment. Hepatic senescence protein markers such as β-galactosidase, p53, and p21, as well as the inflammatory mediator, IL-6, were examined. The D-galactose-treated rats exhibited increases in AST and γ-GT plasma levels and β-galactosidase protein expression compared to the control group. Swimming exercise significantly reduced BW, epididymal fat mass, γ-GT activity, and p53, p21, and IL-6 protein levels compared to the aging group. These results suggest that a 12-week swimming exercise program suppresses senescence markers and downregulates inflammatory mediator in the liver tissues of D-galactose-induced aging rats.
Food-Dependent Exercise-Induced Anaphylaxis - Kasuistik med hydrolyseret valleprotein

DEFF Research Database (Denmark)

Junker Christensen, Morten

2013-01-01

Formål / Introduktion: Patienter med Food-Dependent Exercise-Induced Anaphylaxis (FDEIA) eller løbershock kan udvikle livstruende allergiske reaktioner (anafylaksi), når de kombinere fysisk anstrengelse med samtidig indtagelse af et normalt tolereret fødeemne - oftest hvede. Hydrolysering af prot...
EXERCISE-INDUCED ASTHMA

African Journals Online (AJOL)

Enrique

to a repeat bout of intense exercise within 2 hours after an initial. EIA response. In this ... advantage of athletes, if the athlete then competes following a warm-up in this .... Diagnostic and therapeutic algorithm in the work-up of the athlete with EIA. .... Avoid exercise in excessively cold Reduced responsiveness of airways.
Role of PGC-1{alpha} in exercise and fasting induced adaptations in mouse liver

DEFF Research Database (Denmark)

Haase, Tobias Nørresø; Jørgensen, Stine Ringholm; Leick, Lotte

2011-01-01

The transcriptional coactivator peroxisome proliferator activated receptor (PPAR)-¿ coactivator (PGC)-1a plays a role in regulation of several metabolic pathways. By use of whole body PGC-1a knockout (KO) mice we investigated the role of PGC-1a in fasting, acute exercise and exercise training ind...... role in regulation of Cyt c and COXI expression in the liver in response to a single exercise bout and prolonged exercise training, which implies that exercise training induced improvements in oxidative capacity of the liver is regulated by PGC-1a.......The transcriptional coactivator peroxisome proliferator activated receptor (PPAR)-¿ coactivator (PGC)-1a plays a role in regulation of several metabolic pathways. By use of whole body PGC-1a knockout (KO) mice we investigated the role of PGC-1a in fasting, acute exercise and exercise training...... induced regulation of key proteins in gluconeogenesis and metabolism in the liver. In both wild type (WT) and PGC-1a KO mice liver, the mRNA content of the gluconeogenic proteins glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) was upregulated during fasting. Pyruvate...
Bronchial provocation testing does not detect exercise-induced laryngeal obstruction

DEFF Research Database (Denmark)

Walsted, Emil Schwarz; Hull, James H; Sverrild, Asger

2017-01-01

INTRODUCTION: Exercise-induced laryngeal obstruction (EILO) is a key differential diagnosis for asthma in the presence of exertional respiratory symptoms. Continuous laryngoscopy during exercise (CLE), the current gold standard diagnostic test for EILO, has practical limitations. We aimed...... to establish if inspiratory flow data obtained during standard bronchoprovocation testing, to establish the presence of extra-thoracic hyper-responsiveness, may prove diagnostic for EILO and thus preclude requirement for CLE testing. METHODS: We consecutively evaluated 37 adult subjects with exertional dyspnea...
Exercise-induced silent myocardial ischemia: Evaluation by thallium-201 emission computed tomography

International Nuclear Information System (INIS)

Kurata, C.; Sakata, K.; Taguchi, T.; Kobayashi, A.; Yamazaki, N.

1990-01-01

Factors associated with silent myocardial ischemia (SMI) during exercise testing were studied by means of thallium-201 emission computed tomography (ECT) in 471 patients. Coronary angiography was done in 290, of whom 167 were found to have significant coronary artery disease (CAD). Exercise-induced ischemia and its severity were defined with ECT. During exercise 108 (62%) of 173 patients with ischemia and 57 (50%) of 115 with ischemia and angiographically documented CAD had no chest pain. One third of the patients showed an inconsistency between scintigraphic ischemia and ischemia ST depression. Age, sex, prior myocardial infarction, and diabetes mellitus were not related to SMI. Patients with SMI had less severe ischemia despite a higher peak double product compared to those with painful ischemia. Among 91 with prior myocardial infarction and exercise-induced ischemia, 51 with periinfarction ischemia had a higher frequency of SMI than did 14 with ischemia remote from the prior infarct zone despite similarities in the severity of ischemia. In conclusion, factors localized within ischemic myocardium such as less severe ischemia or adjacency to a prior infarct made SMI more prevalent
Exercise-Induced Hypertrophic and Oxidative Signaling Pathways and Myokine Expression in Fast Muscle of Adult Zebrafish

Directory of Open Access Journals (Sweden)

Mireia Rovira

2017-12-01

Full Text Available Skeletal muscle is a plastic tissue that undergoes cellular and metabolic adaptations under conditions of increased contractile activity such as exercise. Using adult zebrafish as an exercise model, we previously demonstrated that swimming training stimulates hypertrophy and vascularization of fast muscle fibers, consistent with the known muscle growth-promoting effects of exercise and with the resulting increased aerobic capacity of this tissue. Here we investigated the potential involvement of factors and signaling mechanisms that could be responsible for exercise-induced fast muscle remodeling in adult zebrafish. By subjecting zebrafish to swimming-induced exercise, we observed an increase in the activity of mammalian target of rapamycin (mTOR and Mef2 protein levels in fast muscle. We also observed an increase in the protein levels of the mitotic marker phosphorylated histone H3 that correlated with an increase in the protein expression levels of Pax7, a satellite-like cell marker. Furthermore, the activity of AMP-activated protein kinase (AMPK was also increased by exercise, in parallel with an increase in the mRNA expression levels of pgc1α and also of pparda, a β-oxidation marker. Changes in the mRNA expression levels of slow and fast myosin markers further supported the notion of an exercise-induced aerobic phenotype in zebrafish fast muscle. The mRNA expression levels of il6, il6r, apln, aplnra and aplnrb, sparc, decorin and igf1, myokines known in mammals to be produced in response to exercise and to signal through mTOR/AMPK pathways, among others, were increased in fast muscle of exercised zebrafish. These results support the notion that exercise increases skeletal muscle growth and myogenesis in adult zebrafish through the coordinated activation of the mTOR-MEF2 and AMPK-PGC1α signaling pathways. These results, coupled with altered expression of markers for oxidative metabolism and fast-to-slow fiber-type switch, also suggest
Promotion of Myogenic Maturation by Timely Application of Electric Field Along the Topographical Alignment.

Science.gov (United States)

Ko, Ung Hyun; Park, Sukhee; Bang, Hyunseung; Kim, Mina; Shin, Hyunjun; Shin, Jennifer H

2018-05-01

Engineered muscular substitutes can restore the impaired muscle functions when integrated properly into the host tissue. To generate functional muscles with sufficient contractility at the site of transplant, the in vitro construction of fully differentiated muscle fibers would be desired. Many previous reports have identified either topographical alignment or electrical stimulation as an effective tool to promote myogenic differentiation. However, optimization of spatial and temporal arrangement of these two physical cues for better differentiation and maturation of skeletal muscles has not been investigated. In this article, we introduce a novel cell culture system that allows simultaneous application of these two independent directional cues at both orthogonal and parallel arrangements. We then show that the parallel arrangement of the aligned topography and the electric field synergistically facilitates better differentiation and maturation of C2C12, generating myotubes with more fused nuclei. Addition of the electric stimulation at the late stage of myogenic differentiation is found to further improve cell fusion to form multinucleate myotubes through a phosphatidylinositol-3-OH-kinase-dependent pathway. As such, we successfully demonstrated that the combined stimulation of topographical and electrical cues could effectively enhance both myogenic differentiation and maturation in a temporal and orientation-dependent manner, providing the basis for therapeutic strategies for regenerative tissue engineering.
Zinc Is Indispensable in Exercise-Induced Cardioprotection against Intermittent Hypoxia-Induced Left Ventricular Function Impairment in Rats.

Directory of Open Access Journals (Sweden)

Tsung-I Chen

Full Text Available In obstructive sleep apnea (OSA, recurrent obstruction of the upper airway leads to intermittent hypoxia (IH during sleep, which can result in impairment of cardiac function. Although exercise can have beneficial effects against IH-induced cardiac dysfunction, the mechanism remains unclear. This study aimed to investigate the interactions of zinc and exercise on IH-triggered left ventricular dysfunction in a rat model that mimics IH in OSA patients. Nine-week-old male Sprague-Dawley rats were randomly assigned to either a control group (CON or to a group receiving 10 weeks of exercise training (EXE. During weeks 9 and 10, half the rats in each group were subjected to IH for 8 h per day for 14 days (IHCON, IHEXE, whereas the remainder continued to breathe room air. Rats within each of the CON, IHCON, EXE, and IHEXE groups were further randomly assigned to receive intraperitoneal injections of either zinc chloride, the zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl ethylenediamine (TPEN, or injection vehicle only. IH induced a lower left ventricular fractional shortening, reduced ejection fraction, higher myocardial levels of inflammatory factors, increased levels oxidative stress, and lower levels of antioxidative capacity, all of which were abolished by zinc treatment. IHEXE rats exhibited higher levels of cardiac function and antioxidant capacity and lower levels of inflammatory factors and oxidative stress than IHCON rats; however, IHEXE rats receiving TPEN did not exhibit these better outcomes. In conclusion, zinc is required for protecting against IH-induced LV functional impairment and likely plays a critical role in exercise-induced cardioprotection by exerting a dual antioxidant and anti-inflammatory effect.
Zinc Is Indispensable in Exercise-Induced Cardioprotection against Intermittent Hypoxia-Induced Left Ventricular Function Impairment in Rats

Science.gov (United States)

Chen, Michael Yu-Chih

2016-01-01

In obstructive sleep apnea (OSA), recurrent obstruction of the upper airway leads to intermittent hypoxia (IH) during sleep, which can result in impairment of cardiac function. Although exercise can have beneficial effects against IH-induced cardiac dysfunction, the mechanism remains unclear. This study aimed to investigate the interactions of zinc and exercise on IH-triggered left ventricular dysfunction in a rat model that mimics IH in OSA patients. Nine-week-old male Sprague-Dawley rats were randomly assigned to either a control group (CON) or to a group receiving 10 weeks of exercise training (EXE). During weeks 9 and 10, half the rats in each group were subjected to IH for 8 h per day for 14 days (IHCON, IHEXE), whereas the remainder continued to breathe room air. Rats within each of the CON, IHCON, EXE, and IHEXE groups were further randomly assigned to receive intraperitoneal injections of either zinc chloride, the zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN), or injection vehicle only. IH induced a lower left ventricular fractional shortening, reduced ejection fraction, higher myocardial levels of inflammatory factors, increased levels oxidative stress, and lower levels of antioxidative capacity, all of which were abolished by zinc treatment. IHEXE rats exhibited higher levels of cardiac function and antioxidant capacity and lower levels of inflammatory factors and oxidative stress than IHCON rats; however, IHEXE rats receiving TPEN did not exhibit these better outcomes. In conclusion, zinc is required for protecting against IH-induced LV functional impairment and likely plays a critical role in exercise-induced cardioprotection by exerting a dual antioxidant and anti-inflammatory effect. PMID:27977796
Regulation of exercise-induced lipid metabolism in skeletal muscle

DEFF Research Database (Denmark)

Jordy, Andreas Børsting; Kiens, Bente

2014-01-01

Exercise increases the utilization of lipids in muscle. The sources of lipids are long-chain fatty acids taken up from the plasma and fatty acids released from stores of intramuscular triacylglycerol by the action of intramuscular lipases. In the present review, we focus on the role of fatty acid...... binding proteins, particularly fatty acid translocase/cluster of differentiation 36 (FAT/CD36), in the exercise- and contraction-induced increase in uptake of long-chain fatty acids in muscle. The FAT/CD36 translocates from intracellular depots to the surface membrane upon initiation of exercise/muscle...... triglyceride lipase in regulation of muscle lipolysis. Although the molecular regulation of the lipases in muscle is not understood, it is speculated that intramuscular lipolysis may be regulated in part by the availability of the plasma concentration of long-chain fatty acids....
Combination of exercise training and diet restriction normalizes limited exercise capacity and impaired skeletal muscle function in diet-induced diabetic mice.

Science.gov (United States)

Suga, Tadashi; Kinugawa, Shintaro; Takada, Shingo; Kadoguchi, Tomoyasu; Fukushima, Arata; Homma, Tsuneaki; Masaki, Yoshihiro; Furihata, Takaaki; Takahashi, Masashige; Sobirin, Mochamad A; Ono, Taisuke; Hirabayashi, Kagami; Yokota, Takashi; Tanaka, Shinya; Okita, Koichi; Tsutsui, Hiroyuki

2014-01-01

Exercise training (EX) and diet restriction (DR) are essential for effective management of obesity and insulin resistance in diabetes mellitus. However, whether these interventions ameliorate the limited exercise capacity and impaired skeletal muscle function in diabetes patients remains unexplored. Therefore, we investigated the effects of EX and/or DR on exercise capacity and skeletal muscle function in diet-induced diabetic mice. Male C57BL/6J mice that were fed a high-fat diet (HFD) for 8 weeks were randomly assigned for an additional 4 weeks to 4 groups: control, EX, DR, and EX+DR. A lean group fed with a normal diet was also studied. Obesity and insulin resistance induced by a HFD were significantly but partially improved by EX or DR and completely reversed by EX+DR. Although exercise capacity decreased significantly with HFD compared with normal diet, it partially improved with EX and DR and completely reversed with EX+DR. In parallel, the impaired mitochondrial function and enhanced oxidative stress in the skeletal muscle caused by the HFD were normalized only by EX+DR. Although obesity and insulin resistance were completely reversed by DR with an insulin-sensitizing drug or a long-term intervention, the exercise capacity and skeletal muscle function could not be normalized. Therefore, improvement in impaired skeletal muscle function, rather than obesity and insulin resistance, may be an important therapeutic target for normalization of the limited exercise capacity in diabetes. In conclusion, a comprehensive lifestyle therapy of exercise and diet normalizes the limited exercise capacity and impaired muscle function in diabetes mellitus.
Resistance exercise-induced fluid shifts: change in active muscle size and plasma volume

Science.gov (United States)

Ploutz-Snyder, L. L.; Convertino, V. A.; Dudley, G. A.

1995-01-01

The purpose of this study was to test the hypothesis that the reduction in plasma volume (PV) induced by resistance exercise reflects fluid loss to the extravascular space and subsequently selective increase in cross-sectional area (CSA) of active but not inactive skeletal muscle. We compared changes in active and inactive muscle CSA and PV after barbell squat exercise. Magnetic resonance imaging (MRI) was used to quantify muscle involvement in exercise and to determine CSA of muscle groups or individual muscles [vasti (VS), adductor (Add), hamstring (Ham), and rectus femoris (RF)]. Muscle involvement in exercise was determined using exercise-induced contrast shift in spin-spin relaxation time (T2)-weighted MR images immediately postexercise. Alterations in muscle size were based on the mean CSA of individual slices. Hematocrit, hemoglobin, and Evans blue dye were used to estimate changes in PV. Muscle CSA and PV data were obtained preexercise and immediately postexercise and 15 and 45 min thereafter. A hierarchy of muscle involvement in exercise was found such that VS > Add > Ham > RF, with the Ham and RF showing essentially no involvement. CSA of the VS and Add muscle groups were increased 10 and 5%, respectively, immediately after exercise in each thigh with no changes in Ham and RF CSA. PV was decreased 22% immediately following exercise. The absolute loss of PV was correlated (r2 = 0.75) with absolute increase in muscle CSA immediately postexercise, supporting the notion that increased muscle size after resistance exercise reflects primarily fluid movement from the vascular space into active but not inactive muscle.
Muscle satellite cell heterogeneity and self-renewal

Science.gov (United States)

Motohashi, Norio; Asakura, Atsushi

2014-01-01

Adult skeletal muscle possesses extraordinary regeneration capacities. After muscle injury or exercise, large numbers of newly formed muscle fibers are generated within a week as a result of expansion and differentiation of a self-renewing pool of muscle stem cells termed muscle satellite cells. Normally, satellite cells are mitotically quiescent and reside beneath the basal lamina of muscle fibers. Upon regeneration, satellite cells are activated, and give rise to daughter myogenic precursor cells. After several rounds of proliferation, these myogenic precursor cells contribute to the formation of new muscle fibers. During cell division, a minor population of myogenic precursor cells returns to quiescent satellite cells as a self-renewal process. Currently, accumulating evidence has revealed the essential roles of satellite cells in muscle regeneration and the regulatory mechanisms, while it still remains to be elucidated how satellite cell self-renewal is molecularly regulated and how satellite cells are important in aging and diseased muscle. The number of satellite cells is decreased due to the changing niche during ageing, resulting in attenuation of muscle regeneration capacity. Additionally, in Duchenne muscular dystrophy (DMD) patients, the loss of satellite cell regenerative capacity and decreased satellite cell number due to continuous needs for satellite cells lead to progressive muscle weakness with chronic degeneration. Thus, it is necessary to replenish muscle satellite cells continuously. This review outlines recent findings regarding satellite cell heterogeneity, asymmetric division and molecular mechanisms in satellite cell self-renewal which is crucial for maintenance of satellite cells as a muscle stem cell pool throughout life. In addition, we discuss roles in the stem cell niche for satellite cell maintenance, as well as related cell therapies for approaching treatment of DMD. PMID:25364710
Muscle Satellite Cell Heterogeneity and Self-Renewal

Directory of Open Access Journals (Sweden)

Norio eMotohashi

2014-01-01

Full Text Available Adult skeletal muscle possesses extraordinary regeneration capacities. After muscle injury or exercise, large numbers of newly formed muscle fibers are generated within a week as a result of expansion and differentiation of a self-renewing pool of muscle stem cells termed muscle satellite cells. Normally, satellite cells are mitotically quiescent and reside beneath the basal lamina of muscle fibers. Upon regeneration, satellite cells are activated, and give rise to daughter myogenic precursor cells. After several rounds of proliferation, these myogenic precursor cells contribute to the formation of new muscle fibers. During cell division, a minor population of myogenic precursor cells returns to quiescent satellite cells as a self-renewal process. Currently, accumulating evidence has revealed the essential roles of satellite cells in muscle regeneration and the regulatory mechanisms, while it still remains to be elucidated how satellite cell self-renewal is molecularly regulated and how satellite cells are important in aging and diseased muscle. The number of satellite cells is decreased due to the changing niche during ageing, resulting in attenuation of muscle regeneration capacity. Additionally, in Duchenne muscular dystrophy (DMD patients, the loss of satellite cell regenerative capacity and decreased satellite cell number due to continuous needs for satellite cells lead to progressive muscle weakness with chronic degeneration. Thus, it is necessary to replenish muscle satellite cells continuously. This review outlines recent findings regarding satellite cell heterogeneity, asymmetric division and molecular mechanisms in satellite cell self-renewal which is crucial for maintenance of satellite cells as a muscle stem cell pool throughout life. In addition, we discuss roles in the stem cell niche for satellite cell maintenance, as well as related cell therapies for approaching treatment of DMD.
The Tocotrienol-Rich Fraction Is Superior to Tocopherol in Promoting Myogenic Differentiation in the Prevention of Replicative Senescence of Myoblasts.

Directory of Open Access Journals (Sweden)

Shy Cian Khor

Full Text Available Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF and α-tocopherol (ATF in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal expression, myogenic differentiation and myogenic regulatory factors (MRFs expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.
Relative workload determines exercise-induced increases in PGC-1alpha mRNA

DEFF Research Database (Denmark)

Nordsborg, Nikolai Baastrup; Lundby, Carsten; Leick, Lotte

2010-01-01

INTRODUCTION:: The hypothesis that brief intermittent exercise induced increases in human skeletal muscle metabolic mRNA is dependent on relative workload was investigated. METHODS:: Trained (n=10) and untrained (n=8) subjects performed exhaustive intermittent cycling exercise (4x4 min @ 85% of VO2...... peak, interspersed by 3 min). Trained subjects also performed the intermittent exercise at the same absolute workload as untrained, corresponding to 70% of VO2 peak (n=6). RESULTS:: Exercise at 85% of VO2 peak elevated (P... and untrained, respectively. PGC-1alpha mRNA expression was increased (Pelevated (3.1+/-0.7 mM) and PGC-1alpha mRNA content was less (P
Exercise-induced rib stress fractures: influence of reduced bone mineral density

DEFF Research Database (Denmark)

Vinther, Anders; Kanstrup, Inge-Lis; Christiansen, Erik

2005-01-01

study investigated BMD in seven Danish national team rowers with previous rib stress fracture (RSF) and 7 controls (C) matched for gender, age, height, weight and training experience. Total body scan and specific scans of the lumbar spine (L2-L4), femoral neck and distal radius were performed using......Exercise-induced rib stress fractures have been reported frequently in elite rowers during the past decade. The etiology of rib stress fractures is unclear, but low bone mineral density (BMD) has been suggested to be a potential risk factor for stress fractures in weight-bearing bones. The present...... density may be a potential risk factor for the development of exercise-induced rib stress fractures in elite rowers....
Surgical treatment is effective in severe cases of exercise-induced laryngeal obstruction: A follow-up study.

Science.gov (United States)

Norlander, Katarina; Johansson, Henrik; Jansson, Christer; Nordvall, Lennart; Nordang, Leif

2015-01-01

Surgery is an effective treatment in severe cases of supraglottic exercise-induced laryngeal obstruction (E-ILO). Conservatively treated subjects and subjects tested negative for E-ILO, who still experience breathing problems 1-3 years after diagnosis, tend to adjust their physical activity to a greater extent than surgically treated subjects. To investigate how symptoms and level of physical activity change over time in patients with E-ILO who have undergone surgery, patients with E-ILO treated conservatively and patients who tested negative for laryngeal obstruction at continuous laryngoscopy exercise-test (CLE-test). Patients referred for exercise-induced breathing difficulties answered questionnaires at diagnostic CLE-test and at follow-up. Questions regarded exercise-induced breathing problems, current physical activity level, and medical history of asthma and perennial allergy. Out of 84 invited subjects, 59 (70%) answered both questionnaires. Surgically treated subjects had less breathing problems at follow-up compared with conservatively treated subjects and subjects who tested negative (p < 0.001). None of the surgically treated subjects were less physically active or had changed sport due to exercise-induced dyspnoea, whereas 41.7% of the conservatively treated subjects had made such adjustments (p < 0.001).

Exercise-induced dyspnea is a problem among the general adolescent population.

Science.gov (United States)

Johansson, H; Norlander, K; Hedenström, H; Janson, C; Nordang, L; Nordvall, L; Emtner, M

2014-06-01

Respiratory symptoms during exercise are common and might limit adolescents' ability to take part in physical activity. To estimate the prevalence, determinants and consequences of exercise-induced dyspnea (EID) on daily life in a general population of 12-13 year old adolescents. A letter was sent to the parents of all 12-13 year old adolescents in the city of Uppsala (n = 3838). Parents were asked to complete a questionnaire together with their child on EID, asthma and allergy, consequences for daily life (wheeze, day time- and nocturnal dyspnea) and physical activity. The response rate was 60% (n = 2309). Fourteen percent (n = 330) reported EID, i.e. had experienced an attack of shortness of breath that occurred after strenuous activity within the last 12 months. Female gender, ever-asthma and rhinitis were independently associated with an increased risk of EID. Ever-asthma was reported by 14.6% (n = 338), and 5.4% (n = 128) had both EID and ever-asthma. Sixty-one percent (n = 202) of the participants with EID did not have a diagnosis of asthma. In addition to rhinitis, participants with EID reported current wheeze and day-time as well as nocturnal dyspnea more often than the group without EID. No difference was found in the level of physical activity between participants with and without EID. Adolescents with undiagnosed exercise-induced dyspnea have respiratory symptoms and are affected in daily life but have the same level of physical activity as adolescents without exercise-induced respiratory symptoms. Copyright © 2014 Elsevier Ltd. All rights reserved.
Understanding Key Mechanisms of Exercise-Induced Cardiac Protection to Mitigate Disease: Current Knowledge and Emerging Concepts.

Science.gov (United States)

Bernardo, Bianca C; Ooi, Jenny Y Y; Weeks, Kate L; Patterson, Natalie L; McMullen, Julie R

2018-01-01

The benefits of exercise on the heart are well recognized, and clinical studies have demonstrated that exercise is an intervention that can improve cardiac function in heart failure patients. This has led to significant research into understanding the key mechanisms responsible for exercise-induced cardiac protection. Here, we summarize molecular mechanisms that regulate exercise-induced cardiac myocyte growth and proliferation. We discuss in detail the effects of exercise on other cardiac cells, organelles, and systems that have received less or little attention and require further investigation. This includes cardiac excitation and contraction, mitochondrial adaptations, cellular stress responses to promote survival (heat shock response, ubiquitin-proteasome system, autophagy-lysosomal system, endoplasmic reticulum unfolded protein response, DNA damage response), extracellular matrix, inflammatory response, and organ-to-organ crosstalk. We summarize therapeutic strategies targeting known regulators of exercise-induced protection and the challenges translating findings from bench to bedside. We conclude that technological advancements that allow for in-depth profiling of the genome, transcriptome, proteome and metabolome, combined with animal and human studies, provide new opportunities for comprehensively defining the signaling and regulatory aspects of cell/organelle functions that underpin the protective properties of exercise. This is likely to lead to the identification of novel biomarkers and therapeutic targets for heart disease.
Role of T-type calcium channels in myogenic tone of skeletal muscle resistance arteries

DEFF Research Database (Denmark)

VanBavel, Ed; Sorop, Oana; Andreasen, Ditte

2002-01-01

T-type calcium channels may be involved in the maintenance of myogenic tone. We tested their role in isolated rat cremaster arterioles obtained after CO(2) anesthesia and decapitation. Total RNA was analyzed by RT-PCR and Southern blotting for calcium channel expression. We observed expression...... of voltage-operated calcium (Ca(V)) channels Ca(V)3.1 (T-type), Ca(V)3.2 (T-type), and Ca(V)1.2 (L-type) in cremaster arterioles (n = 3 rats). Amplification products were observed only in the presence of reverse transcriptase and cDNA. Concentration-response curves of the relatively specific L-type blocker......); K(+) -5.4 +/- 0.3 (n = 4); all log(IC(50)) P maintenance of myogenic tone in rat cremaster muscle arterioles....
FTO genotype is associated with exercise training-induced changes in body composition

Science.gov (United States)

Rankinen, Tuomo; Rice, Treva; Teran-Garcia, Margarita; Rao, D.C.; Bouchard, Claude

2010-01-01

The fat mass and obesity associated (FTO) gene is the first obesity-susceptibility gene identified by genome-wide association scans and confirmed in several follow-up studies. Homozygotes for the risk allele (A/A) have 1.67 times greater risk of obesity than those who do not have the allele. However, it is not known if regular exercise-induced changes in body composition are influenced by the FTO genotype. The purpose of our study was to test if the FTO genotype is associated with exercise-induced changes in adiposity. Body composition was derived from underwater weighing before and after a 20-week endurance training program in 481 previously sedentary white subjects of the HERITAGE Family Study. FTO SNP rs8050136 was genotyped using Illumina GoldenGate assay. In the sedentary state, the A/A homozygotes were significantly heavier and fatter than the heterozygotes and the C/C homozygotes in men (p=0.004) but not in women (p=0.331; gene-by-sex interaction p=0.0053). The FTO genotype was associated with body fat responses to regular exercise (p<0.005; adjusted for age, sex, and baseline value of response trait): carriers of the C-allele showed three times greater fat mass and %body fat losses than the A/A homozygotes. The FTO genotype explained 2% of the variance in adiposity changes. Our data suggest that the FTO obesity-susceptibility genotype influences the body fat responses to regular exercise. Resistance to exercise-induced reduction in total adiposity may represent one mechanism by which the FTO A allele promotes overweight and obesity. PMID:19543202
Muscle satellite cells are activated after exercise to exhaustion in Thoroughbred horses.

Science.gov (United States)

Kawai, M; Aida, H; Hiraga, A; Miyata, H

2013-07-01

Although satellite cells are well known as muscle stem cells capable of adding myonuclei during muscle repair and hypertrophy, the response of satellite cells in horse muscles to a run to exhaustion is still unknown. To investigate the time course of satellite cell activation in Thoroughbred horse muscle after running to exhaustion. We hypothesised that this type of intense exercise would induce satellite cell activation in skeletal muscle similar to a resistance exercise. Nine de-trained Thoroughbred horses (6 geldings and 3 mares) aged 3-6 years were studied. Biopsy samples were taken from the gluteus medius muscle of the horses before and 1 min, 3 h, 1 day, 3 days, 1 week and 2 weeks after a treadmill run to exhaustion. The numbers of satellite cells for each fibre type were determined by using immunofluorescence staining. Total RNA was extracted from these samples, and the expressions of interleukin (IL)-6, paired box transcriptional factor (Pax) 7, myogenic differentiation 1 (MyoD), myogenin, proliferating cell nuclear antigen (PCNA), insulin-like growth factor (IGF)-I and hepatocyte growth factor (HGF) mRNA were analysed using real-time reverse transcription-PCR. The numbers of satellite cells were significantly increased in type I and IIa fibres at 1 week and in type IIa/x fibre at 2 weeks post exercise. The expression of IL-6 mRNA increased significantly by 3 h post exercise. The expression of PCNA mRNA also increased by 1 day after running, indicating that running can initiate satellite cell proliferation. The expression of Pax7, MyoD, myogenin, IGF-I and HGF mRNA peaked at 1 week post exercise. Satellite cell activation and proliferation could be enhanced after a run to exhaustion without detectable injury as assessed by the histochemical analysis. Understanding the response of satellite cell activation to running exercise provides fundamental information about the skeletal muscle adaptation in Thoroughbred horses. © 2012 EVJ Ltd.
EXERCISE-INDUCED VENTRICULAR-TACHYCARDIA - A RARE MANIFESTATION OF DIGITALIS TOXICITY

NARCIS (Netherlands)

GOSSELINK, ATM; CRIJNS, HJGM; WIESFELD, ACP; LIE, KI

Digitalis intoxication is one of the most common adverse drug reactions. Although some arrhythmias are seen more frequently than others, virtually any rhythm disturbance, including ventricular tachycardia, may occur. However, to our knowledge, exercise-induced ventricular tachycardia as a
Heat and exercise acclimation increases intracellular levels of Hsp72 and inhibits exercise-induced increase in intracellular and plasma Hsp72 in humans.

Science.gov (United States)

Magalhães, Flávio de Castro; Amorim, Fabiano Trigueiro; Passos, Renata L Freitas; Fonseca, Michele Atalla; Oliveira, Kenya Paula Moreira; Lima, Milene Rodrigues Malheiros; Guimarães, Juliana Bohen; Ferreira-Júnior, João Batista; Martini, Angelo R P; Lima, Nilo R V; Soares, Danusa Dias; Oliveira, Edilamar Menezes; Rodrigues, Luiz Oswaldo Carneiro

2010-11-01

In order to verify the effects of heat and exercise acclimation (HA) on resting and exercise-induced expression of plasma and leukocyte heat shock protein 72 (Hsp72) in humans, nine healthy young male volunteers (25.0 ± 0.7 years; 80.5 ± 2.0 kg; 180 ± 2 cm, mean ± SE) exercised for 60 min in a hot, dry environment (40 ± 0°C and 45 ± 0% relative humidity) for 11 days. The protocol consisted of running on a treadmill using a controlled hyperthermia technique in which the work rate was adjusted to elevate the rectal temperature by 1°C in 30 min and maintain it elevated for another 30 min. Before and after the HA, the volunteers performed a heat stress test (HST) at 50% of their individual maximal power output for 90 min in the same environment. Blood was drawn before (REST), immediately after (POST) and 1 h after (1 h POST) HST, and plasma and leukocytes were separated and stored. Subjects showed expected adaptations to HA: reduced exercise rectal and mean skin temperatures and heart rate, and augmented sweat rate and exercise tolerance. In HST1, plasma Hsp72 increased from REST to POST and then returned to resting values 1 h POST (REST: 1.11 ± 0.07, POST: 1.48 ± 0.10, 1 h POST: 1.22 ± 0.11 ng mL(-1); p 0.05). HA increased resting levels of intracellular Hsp72 (HST1: 1 ± 0.02 and HST2: 4.2 ± 1.2 density units, p 0.05). Regression analysis showed that the lower the pre-exercise expression of intracellular Hsp72, the higher the exercise-induced increase (R = -0.85, p < 0.05). In conclusion, HA increased resting leukocyte Hsp72 levels and inhibited exercise-induced expression. This intracellular adaptation probably induces thermotolerance. In addition, the non-increase in plasma Hsp72 after HA may be related to lower stress at the cellular level in the acclimated individuals.
Exercise attenuates intermittent hypoxia-induced cardiac fibrosis associated with sodium-hydrogen exchanger-1 in rats

Directory of Open Access Journals (Sweden)

Tsung-I Chen

2016-10-01

Full Text Available Purpose: To investigate the role of sodium–hydrogen exchanger-1 (NHE-1 and exercise training on intermittent hypoxia-induced cardiac fibrosis in obstructive sleep apnea (OSA, using an animal model mimicking the intermittent hypoxia of OSA. Methods: Eight-week-old male Sprague–Dawley rats were randomly assigned to control (CON, intermittent hypoxia (IH, exercise (EXE or IH combined with exercise (IHEXE groups. These groups were randomly assigned to subgroups receiving either a vehicle or the NHE-1 inhibitor cariporide. The EXE and IHEXE rats underwent exercise training on an animal treadmill for 10 weeks (5 days/week, 60 minutes/day, 24–30 m/minute, 2–10% grade. The IH and IHEXE rats were exposed to 14 days of IH (30 seconds of hypoxia - nadir of 2-6% O2 - followed by 45 seconds of normoxia for 8 hours/day. At the end of 10 weeks, rats were sacrificed and then hearts were removed to determine the myocardial levels of fibrosis index, oxidative stress, antioxidant capacity and NHE-1 activation. Results: Compared to the CON rats, IH induced higher cardiac fibrosis, lower myocardial catalase and superoxidative dismutase activities, higher myocardial lipid and protein peroxidation and higher NHE-1 activation (p < 0.05 for each, which were all abolished by cariporide. Compared to the IH rats, lower cardiac fibrosis, higher myocardial antioxidant capacity, lower myocardial lipid and protein peroxidation and lower NHE-1 activation were found in the IHEXE rats (p < 0.05 for each. Conclusion: IH-induced cardiac fibrosis was associated with NHE-1 hyperactivity. However, exercise training and cariporide exerted an inhibitory effect to prevent myocardial NHE-1 hyperactivity, which contributed to reduced IH-induced cardiac fibrosis. Therefore, NHE-1 plays a critical role in the effect of exercise on IH-induced increased cardiac fibrosis.
Diagnostic value of exercise-induced changes in circulating high sensitive troponin T in stable chest pain patients

DEFF Research Database (Denmark)

Mouridsen, Mette Rauhe; Nielsen, Olav Wendelboe; Pedersen, Ole Dyg

2013-01-01

We investigated the diagnostic value of exercise-induced increase in cardiac Troponin T (cTnT) in stable chest pain subjects.......We investigated the diagnostic value of exercise-induced increase in cardiac Troponin T (cTnT) in stable chest pain subjects....
Effect of acute moderate exercise on induced inflammation and arterial function in older adults.

Science.gov (United States)

Ranadive, Sushant Mohan; Kappus, Rebecca Marie; Cook, Marc D; Yan, Huimin; Lane, Abbi Danielle; Woods, Jeffrey A; Wilund, Kenneth R; Iwamoto, Gary; Vanar, Vishwas; Tandon, Rudhir; Fernhall, Bo

2014-04-01

Acute inflammation reduces flow-mediated vasodilatation and increases arterial stiffness in young healthy individuals. However, this response has not been studied in older adults. The aim of this study, therefore, was to evaluate the effect of acute induced systemic inflammation on endothelial function and wave reflection in older adults. Furthermore, an acute bout of moderate-intensity aerobic exercise can be anti-inflammatory. Taken together, we tested the hypothesis that acute moderate-intensity endurance exercise, immediately preceding induced inflammation, would be protective against the negative effects of acute systemic inflammation on vascular function. Fifty-nine healthy volunteers between 55 and 75 years of age were randomized to an exercise or a control group. Both groups received a vaccine (induced inflammation) and sham (saline) injection in a counterbalanced crossover design. Inflammatory markers, endothelial function (flow-mediated vasodilatation) and measures of wave reflection and arterial stiffness were evaluated at baseline and at 24 and 48 h after injections. There were no significant differences in endothelial function and arterial stiffness between the exercise and control group after induced inflammation. The groups were then analysed together, and we found significant differences in the inflammatory markers 24 and 48 h after induction of acute inflammation compared with sham injection. However, flow-mediated vasodilatation, augmentation index normalized for heart rate (AIx75) and β-stiffness did not change significantly. Our results suggest that acute inflammation induced by influenza vaccination did not affect endothelial function in older adults.
Does a Rehabilitation Program of Aerobic and Progressive Resisted Exercises Influence HIV-Induced Distal Neuropathic Pain?

Science.gov (United States)

Maharaj, Sonill S; Yakasai, Abdulsalam M

2018-05-01

Distal symmetrical polyneuropathy is a common neurological sequela after HIV, which leads to neuropathic pain and functional limitations. Rehabilitation programs with exercises are used to augment pharmacological therapy to relieve pain but appropriate and effective exercises are unknown. This study explored the safety and effect of moderate-intensity aerobic exercises and progressive resisted exercises for HIV-induced distal symmetrical polyneuropathy neuropathic pain. A randomized pretest, posttest of 12 wks of aerobic exercise or progressive resisted exercise compared with a control. Outcome measures were assessed using the subjective periphery neuropathy, brief peripheral neuropathy screening, and numeric pain rating scale. Pain was assessed at baseline, 6 and 12 wks. Data between groups were compared using Kruskal-Wallis, Mann-Whitney U test, and within-groups Friedman and Wilcoxon signed rank tests. There were 136 participants (mean [SD] age = 36.79 [8.23] yrs) and the exercise groups completed the protocols without any adverse effects. Pain scores within and between aerobic exercise and progressive resisted exercise groups showed significant improvement (P 0.05). This study supports a rehabilitation program of moderate-intensity aerobic exercise and progressive resisted exercise being safe and effective for reducing neuropathic pain and is beneficial with analgesics for HIV-induced distal symmetrical polyneuropathy.
Prior exercise training blunts short-term high-fat diet-induced weight gain.

Science.gov (United States)

Snook, Laelie A; MacPherson, Rebecca E K; Monaco, Cynthia M F; Frendo-Cumbo, Scott; Castellani, Laura; Peppler, Willem T; Anderson, Zachary G; Buzelle, Samyra L; LeBlanc, Paul J; Holloway, Graham P; Wright, David C

2016-08-01

High-fat diets rapidly cause weight gain and glucose intolerance. We sought to determine whether these changes could be mitigated with prior exercise training. Male C57BL/6J mice were exercise-trained by treadmill running (1 h/day, 5 days/wk) for 4 wk. Twenty-four hours after the final bout of exercise, mice were provided with a high-fat diet (HFD; 60% kcal from lard) for 4 days, with no further exercise. In mice fed the HFD prior to exercise training, the results were blunted weight gain, reduced fat mass, and a slight attenuation in glucose intolerance that was mirrored by greater insulin-induced Akt phosphorylation in skeletal muscle compared with sedentary mice fed the HFD. When ad libitum-fed sedentary mice were compared with sedentary high-fat fed mice that were calorie restricted (-30%) to match the weight gain of the previously trained high-fat fed mice, the same attenuated impairments in glucose tolerance were found. Blunted weight gain was associated with a greater capacity to increase energy expenditure in trained compared with sedentary mice when challenged with a HFD. Although mitochondrial enzymes in white adipose tissue and UCP-1 protein content in brown adipose tissue were increased in previously exercised compared with sedentary mice fed a HFD, ex vivo mitochondrial respiration was not increased in either tissue. Our data suggest that prior exercise training attenuates high-fat diet-induced weight gain and glucose intolerance and is associated with a greater ability to increase energy expenditure in response to a high-fat diet. Copyright © 2016 the American Physiological Society.
Pain trajectory and exercise-induced pain flares during 8 weeks of neuromuscular exercise in individuals with knee and hip pain.

Science.gov (United States)

Sandal, L F; Roos, E M; Bøgesvang, S J; Thorlund, J B

2016-04-01

Patients considering or engaged in exercise as treatment may expect or experience transient increases in joint pain, causing fear of exercise and influencing compliance. This study investigated the pain trajectory during an 8-week neuromuscular exercise (NEMEX) program together with acute exercise-induced pain flares in persons with knee or hip pain. Individuals above 35 years self-reporting persistent knee or hip pain for the past 3 months were offered 8 weeks of supervised NEMEX, performed in groups twice weekly. The program consisted of 11 exercises focusing on joint stability and neuromuscular control. Participants self-reported joint pain on a 0-10 numerical rating scale (NRS) at baseline and 8-weeks follow-up. NRS pain ratings were also collected before and immediately after every attended exercise session. Joint pain was reduced from baseline (NRS 3.6; 95% CI 3.2-4.1) to 8-weeks follow-up (2.6; 95% CI 2.1-3.1), (P neuromuscular exercise. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Low Fat Loss Response after Medium-Term Supervised Exercise in Obese Is Associated with Exercise-Induced Increase in Food Reward

Directory of Open Access Journals (Sweden)

Graham Finlayson

2011-01-01

Full Text Available Objective. To examine exercise-induced changes in the reward value of food during medium-term supervised exercise in obese individuals. Subjects/Methods. The study was a 12-week supervised exercise intervention prescribed to expend 500 kcal/day, 5 d/week. 34 sedentary obese males and females were identified as responders (R or non-responders (NR to the intervention according to changes in body composition relative to measured energy expended during exercise. Food reward (ratings of liking and wanting, and relative preference by forced choice pairs for an array of food images was assessed before and after an acute exercise bout. Results. 20 responders and 14 non-responders were identified. R lost 5.2 kg ± 2.4 of total fat mass and NR lost 1.7 kg ± 1.4. After acute exercise, liking for all foods increased in NR compared to no change in R. Furthermore, NR showed an increase in wanting and relative preference for high-fat sweet foods. These differences were independent of 12-weeks regular exercise and weight loss. Conclusion. Individuals who showed an immediate post-exercise increase in liking and increased wanting and preference for high-fat sweet foods displayed a smaller reduction in fat mass with exercise. For some individuals, exercise increases the reward value of food and diminishes the impact of exercise on fat loss.
A Comparison of Exercise-Induced Muscle Damage Following Maximal Eccentric Contractions in Men and Boys.

Science.gov (United States)

Deli, Chariklia K; Fatouros, Ioannis G; Paschalis, Vassilis; Georgakouli, Kalliopi; Zalavras, Athanasios; Avloniti, Alexandra; Koutedakis, Yiannis; Jamurtas, Athanasios Z

2017-08-01

Research regarding exercise-induced muscle-damage mainly focuses on adults. The present study examined exercise-induced muscle-damage responses in adults compared with children. Eleven healthy boys (10-12 y) and 15 healthy men (18-45 y) performed 5 sets of 15 maximal eccentric contractions of the knee extensors. Range of motion (ROM), delayed onset muscle soreness (DOMS) during squat and walking, and peak isometric, concentric and eccentric torque were assessed before, post, 24, 48, 72, and 96 hr postexercise. Creatine kinase (CK) activity was assessed before and 72 hr postexercise. Eccentric exercise resulted in DOMS during squat that persisted for up to 96h in men, and 48 hr in boys (p < .05), and DOMS during walking that persisted for up to 72 hr in men, and 48 hr in boys (p < .01). The ROM was lower in both age groups 48 hr postexercise (p < .001). Isometric (p < .001), concentric (p < .01) and eccentric (p < .01) force decreased post, and up to 48 hr postexercise in men. Except for a reduction in isometric force immediately after exercise, no other changes occurred in boys' isokinetic force. CK activity increased in men at 72 hr postexercise compared with pre exercise levels (p = .05). Our data provide further confirmation that children are less susceptible to exercise-induced muscle damage compared with adults.
Meat flavor precursors and factors influencing flavor precursors--A systematic review.

Science.gov (United States)

Khan, Muhammad Issa; Jo, Cheorun; Tariq, Muhammad Rizwan

2015-12-01

Flavor is the sensory impression sensed by taste and smell buds and is a leading factor determining the meat quality and purchasing decision of the consumer. Meat flavor is characteristic of volatiles produced as a result of reactions of non-volatile components that are induced thermally. The water soluble compounds having low molecular weight and meat lipids are important precursors of cooked meat flavor. The Maillard reaction, lipid oxidation, and vitamin degradation are leading reactions during cooking which develop meat flavor from uncooked meat with little aroma and bloody taste. The pre-slaughter and postmortem factors like animal breed, sex, age, feed, aging and cooking conditions contribute to flavor development of cooked meat. The objective of this review is to highlight the flavor chemistry, meat flavor precursors and factors affecting meat flavor precursors. Copyright © 2015 Elsevier Ltd. All rights reserved.
Understanding the electron-stimulated surface reactions of organometallic complexes to enable design of precursors for electron beam-induced deposition

Energy Technology Data Exchange (ETDEWEB)

Spencer, Julie A.; Rosenberg, Samantha G.; Barclay, Michael; Fairbrother, D. Howard [Johns Hopkins University, Department of Chemistry, Baltimore, MD (United States); Wu, Yung-Chien; McElwee-White, Lisa [University of Florida, Department of Chemistry, Gainesville, FL (United States)

2014-12-15

Standard practice in electron beam-induced deposition (EBID) is to use precursors designed for thermal processes, such as chemical vapor deposition (CVD). However, organometallic precursors that yield pure metal deposits in CVD often create EBID deposits with high levels of organic contamination. This contamination negatively impacts the deposit's properties (e.g., by increasing resistivity or decreasing catalytic activity) and severely limits the range of potential applications for metal-containing EBID nanostructures. To provide the information needed for the rational design of precursors specifically for EBID, we have employed an ultra-high vacuum (UHV) surface science approach to identify the elementary reactions of organometallic precursors during EBID. These UHV studies have demonstrated that the initial electron-induced deposition of the surface-bound organometallic precursors proceeds through desorption of one or more of the ligands present in the parent compound. In specific cases, this deposition step has been shown to proceed via dissociative electron attachment, involving low-energy secondary electrons generated by the interaction of the primary beam with the substrate. Electron beam processing of the surface-bound species produced in the initial deposition event usually causes decomposition of the residual ligands, creating nonvolatile fragments. This process is believed to be responsible for a significant fraction of the organic contaminants typically observed in EBID nanostructures. A few ligands (e.g., halogens) can, however, desorb during electron beam processing while other ligands (e.g., PF{sub 3}, CO) can thermally desorb if elevated substrate temperatures are used during deposition. Using these general guidelines for reactivity, we propose some design strategies for EBID precursors. The ultimate goal is to minimize organic contamination and thus overcome the key bottleneck for fabrication of relatively pure EBID nanostructures. (orig.)
Clinical significance of exercise induced ST segment depression after successful percutaneous transluminal coronary angioplasty

International Nuclear Information System (INIS)

Aoki, Toshikazu; Konishi, Tokuji; Futagami, Yasuo

1989-01-01

To evaluate the clinical significance of ST segment depression during repeated Treadmill exercise after successful PTCA, Thallium-201 SPECT was performed. The Thallium-201 SPECT was performed before, one week after and 3-6 months after PTCA. All thirty-five patients had one vessel disease and positive Thallium-201 exercise test. During follow-up period for 3-6 months, 11 of 35 patients had persistent ST segment depression. Restenosis of dilated coronary lesion was demonstrated in 6 of 11 patients. In another 3 of 35 patients, exercise induced ST segment depression was disappered during follow-up Treadmill exercise. In 14 patients with persistent or transient ST segment depression after PTCA, Thallium-201 SPECT demonstrated transient ischemia in 5 of 6 patients with restenosis. In other 8 patients without restenosis, SPECT images did not demonstrate myocardial ischemia and coronary arteriographic findings could not verify side branch stenosis or intimal dissection which might cause myocardial ischemia. The etiology of ST segment depression after successful PTCA in one vessel disease is not produced by exercise induced myocardial ischemia but still unknown mechanisms may be present. (author)
Curcumin and Piperine Supplementation and Recovery Following Exercise Induced Muscle Damage: A Randomized Controlled Trial

Directory of Open Access Journals (Sweden)

Barthélémy Delecroix, Abd Elbasset Abaïdia, Cédric Leduc, Brian Dawson, Grégory Dupont

2017-03-01

Full Text Available The aim of this study was to analyze the effects of oral consumption of curcumin and piperine in combination on the recovery kinetics after exercise-induced muscle damage. Forty-eight hours before and following exercise-induced muscle damage, ten elite rugby players consumed curcumin and piperine (experimental condition or placebo. A randomized cross-over design was performed. Concentric and isometric peak torque for the knee extensors, one leg 6 seconds sprint performance on a non-motorized treadmill, counter movement jump performance, blood creatine kinase concentration and muscle soreness were assessed immediately after exercise, then at 24h, 48h and 72h post-exercise. There were moderate to large effects of the exercise on the concentric peak torque for the knee extensors (Effect size (ES = -1.12; Confidence interval at 90% (CI90%: -2.17 to -0.06, the one leg 6 seconds sprint performance (ES=-1.65; CI90% = -2.51to -0.80 and the counter movement jump performance (ES = -0.56; CI90% = -0.81 to -0.32 in the 48h following the exercise. There was also a large effect of the exercise on the creatine kinase level 72h after the exercise in the control group (ES = 3.61; CI90%: 0.24 to 6.98. This decrease in muscle function and this elevation in creatine kinase indicate that the exercise implemented was efficient to induce muscle damage. Twenty four hours post-exercise, the reduction (from baseline in sprint mean power output was moderately lower in the experimental condition (-1.77 ± 7.25%; 1277 ± 153W in comparison with the placebo condition (-13.6 ± 13.0%; 1130 ± 241W (Effect Size = -1.12; Confidence Interval 90%=-1.86 to -0.86. However, no other effect was found between the two conditions. Curcumin and piperine supplementation before and after exercise can attenuate some, but not all, aspects of muscle damage.
PGC-1alpha mediates exercise-induced skeletal muscle VEGF expression in mice

DEFF Research Database (Denmark)

Leick, Lotte; Hellsten, Ylva; Fentz, Joachim

2009-01-01

The aim of the present study was to test the hypothesis that PGC-1alpha is required for exercise-induced VEGF expression in both young and old mice and that AMPK activation leads to increased VEGF expression through a PGC-1alpha-dependent mechanism. Whole body PGC-1alpha knockout (KO......) and littermate wild-type (WT) mice were submitted to either 1) 5 wk of exercise training, 2) lifelong (from 2 to 13 mo of age) exercise training in activity wheel, 3) a single exercise bout, or 4) 4 wk of daily subcutaneous AICAR or saline injections. In skeletal muscle of PGC-1alpha KO mice, VEGF protein...... expression was approximately 60-80% lower and the capillary-to-fiber ratio approximately 20% lower than in WT. Basal VEGF mRNA expression was similar in WT and PGC-1alpha KO mice, but acute exercise and AICAR treatment increased the VEGF mRNA content in WT mice only. Exercise training of young mice increased...

Profiling of exercise-induced transcripts in the peripheral blood cells of Thoroughbred horses.

Science.gov (United States)

Tozaki, Teruaki; Kikuchi, Mio; Kakoi, Hironaga; Hirota, Kei-Ichi; Mukai, Kazutaka; Aida, Hiroko; Nakamura, Seiji; Nagata, Shun-Ichi

2016-01-01

Transcriptome analyses based on DNA microarray technology have been used to investigate gene expression profiles in horses. In this study, we aimed to identify exercise-induced changes in the expression profiles of genes in the peripheral blood of Thoroughbred horses using DNA microarray technology (15,429 genes on 43,603 probes). Blood samples from the jugular vein were collected from six horses before and 1 min, 4 hr, and 24 hr after all-out running on a treadmill. After the normalization of microarray data, a total of 26,830 probes were clustered into four groups and 11 subgroups showing similar expression changes based on k-mean clustering. The expression level of inflammation-related genes, including interleukin-1 receptor type II (IL-1R2), matrix metallopeptidase 8 (MMP8), protein S100-A8 (S100-A8), and serum amyloid A (SAA), increased at 4 hr after exercise, whereas that of c-Fos (FOS) increased at 1 min after exercise. These results indicated that the inflammatory response increased in the peripheral blood cells after exercise. Our study also revealed the presence of genes that may not be affected by all-out exercise. In conclusion, transcriptome analysis of peripheral blood cells could be used to monitor physiological changes induced by various external stress factors, including exercise, in Thoroughbred racehorses.
Mitophagy is required for mitochondrial biogenesis and myogenic differentiation of C2C12 myoblasts.

Science.gov (United States)

Sin, Jon; Andres, Allen M; Taylor, David J R; Weston, Thomas; Hiraumi, Yoshimi; Stotland, Aleksandr; Kim, Brandon J; Huang, Chengqun; Doran, Kelly S; Gottlieb, Roberta A

2016-01-01

Myogenesis is a crucial process governing skeletal muscle development and homeostasis. Differentiation of primitive myoblasts into mature myotubes requires a metabolic switch to support the increased energetic demand of contractile muscle. Skeletal myoblasts specifically shift from a highly glycolytic state to relying predominantly on oxidative phosphorylation (OXPHOS) upon differentiation. We have found that this phenomenon requires dramatic remodeling of the mitochondrial network involving both mitochondrial clearance and biogenesis. During early myogenic differentiation, autophagy is robustly upregulated and this coincides with DNM1L/DRP1 (dynamin 1-like)-mediated fragmentation and subsequent removal of mitochondria via SQSTM1 (sequestosome 1)-mediated mitophagy. Mitochondria are then repopulated via PPARGC1A/PGC-1α (peroxisome proliferator-activated receptor gamma, coactivator 1 alpha)-mediated biogenesis. Mitochondrial fusion protein OPA1 (optic atrophy 1 [autosomal dominant]) is then briskly upregulated, resulting in the reformation of mitochondrial networks. The final product is a myotube replete with new mitochondria. Respirometry reveals that the constituents of these newly established mitochondrial networks are better primed for OXPHOS and are more tightly coupled than those in myoblasts. Additionally, we have found that suppressing autophagy with various inhibitors during differentiation interferes with myogenic differentiation. Together these data highlight the integral role of autophagy and mitophagy in myogenic differentiation.
β-Hydroxy-β-Methylbutyrate Did Not Enhance High Intensity Resistance Training-Induced Improvements in Myofiber Dimensions and Myogenic Capacity in Aged Female Rats

Science.gov (United States)

Kim, Jeong-Su; Park, Young-Min; Lee, Sang-Rok; Masad, Ihssan S.; Khamoui, Andy V.; Jo, Edward; Park, Bong-Sup; Arjmandi, Bahram H.; Panton, Lynn B.; Lee, Won Jun; Grant, Samuel C.

2012-01-01

Older women exhibit blunted skeletal muscle hypertrophy following resistance training (RT) compared to other age and gender cohorts that is partially due to an impaired regenerative capacity. In the present study, we examined whether β-hydroxy-β-methylbutyrate (HMB) provision to aged female rodents would enhance regenerative mechanisms and facilitate RT-induced myofiber growth. Nineteen-month old female Sprague-Dawley rats were randomly divided into three groups: HMB (0.48 g/kg/d; n = 6), non-HMB (n = 6), and control (n = 4). HMB and non-HMB groups underwent RT every third day for 10 weeks using a ladder climbing apparatus. Whole body strength, grip strength, and body composition was evaluated before and after RT. The gastrocnemius and soleus muscles were analyzed using magnetic resonance diffusion tensor imaging, RT-PCR, and immunohistochemistry to determine myofiber dimensions, transcript expression, and satellite cells/myonuclei, respectively. ANOVAs were used with significance set at p HMB group (+33%) whereas MGF and myogenin increased significantly in both groups (+32–40%). Our findings suggest that HMB did not further enhance intense RT-mediated myogenic mechanisms and myofiber CSA in aged female rats. PMID:23149873
GDNF/GFRα1 Complex Abrogates Self-Renewing Activity of Cortical Neural Precursors Inducing Their Differentiation

Directory of Open Access Journals (Sweden)

Antonela Bonafina

2018-03-01

Full Text Available Summary: The balance between factors leading to proliferation and differentiation of cortical neural precursors (CNPs determines the correct cortical development. In this work, we show that GDNF and its receptor GFRα1 are expressed in the neocortex during the period of cortical neurogenesis. We show that the GDNF/GFRα1 complex inhibits the self-renewal capacity of mouse CNP cells induced by fibroblast growth factor 2 (FGF2, promoting neuronal differentiation. While GDNF leads to decreased proliferation of cultured cortical precursor cells, ablation of GFRα1 in glutamatergic cortical precursors enhances its proliferation. We show that GDNF treatment of CNPs promoted morphological differentiation even in the presence of the self-renewal-promoting factor, FGF2. Analysis of GFRα1-deficient mice shows an increase in the number of cycling cells during cortical development and a reduction in dendrite development of cortical GFRα1-expressing neurons. Together, these results indicate that GDNF/GFRα1 signaling plays an essential role in regulating the proliferative condition and the differentiation of cortical progenitors. : In this article, Ledda and colleagues show that GDNF acting through its receptor GFRα1 plays a critical role in the maturation of cortical progenitors by counteracting FGF2 self-renewal activity on neural stem cells and promoting neuronal differentiation. Keywords: GDNF, GFRα1, cortical precursors, proliferation, postmitotic neurons, neuronal differentiation
Interaction of Wnt Signaling with BMP/Smad Signaling during the Transition from Cell Proliferation to Myogenic Differentiation in Mouse Myoblast-Derived Cells

Directory of Open Access Journals (Sweden)

Kumiko Terada

2013-01-01

Full Text Available Background. Wnt signaling is involved in muscle formation through β-catenin-dependent or -independent pathways, but interactions with other signaling pathways including transforming growth factor β/Smad have not been precisely elucidated. Results. As Wnt4 stimulates myogenic differentiation by antagonizing myostatin (GDF8 activity, we examined the role of Wnt4 signaling during muscle differentiation in the C2C12 myoblast cell line. Among several extrinsic signaling molecules examined in a microarray analysis of C2C12 cells during the transition from cell proliferation to differentiation after mitogen deprivation, bone morphogenetic protein 4 (BMP4 expression was prominently increased. Wnt4 overexpression had similar effects on BMP4 expression. BMP4 was able to inhibit muscle differentiation when added to the culture medium. BMP4 and noggin had no effects on the cellular localization of β-catenin induced by Wnt3a; however, the BMP4-induced phosphorylation of Smad1/5/8 was enhanced by Wnt4, but not by Wnt3a. The BMP antagonist noggin effectively stimulated muscle differentiation through binding to endogenous BMPs, and the effect of noggin was enhanced by the presence of Wnt3a and Wnt4. Conclusion. These results suggest that BMP/Smad pathways are modified through Wnt signaling during the transition from progenitor cell proliferation to myogenic differentiation, although Wnt/β-catenin signaling is not modified with BMP/Smad signaling.
Aging attenuates the interarm diastolic blood pressure difference induced by one-arm exercise.

Science.gov (United States)

Hu, Wei-tong; Li, Ju-xiang; Wang, Ji-wei; Xu, Jin-song; Yang, Qing; Geng, Yong-Jian; Su, Hai; Cheng, Xiao-shu

2013-04-01

It is known that one-arm exercise increases the interarm diastolic blood pressure difference (dIAD) in young individuals, but no research has been carried out in middle-aged and more senior populations. This study aimed to determine whether aging impacts the exercise-induced dIAD in healthy individuals. Normotensive adults (n=120) were recruited and divided into the young (22.5±1.5 years), middle-aged (42.8±4.6 years), and senior (61.0±7.0 years) groups. The right arm exercise involved performing cycling movements at 60 times/min for 3 min. Bilateral brachial blood pressures (BPs) were simultaneously measured using two automatic BP measurement devices before (baseline), immediately (0), 5, 10, and 15 min after the exercise. The difference in bilateral diastolic BPs was calculated as BP l-r and its absolute value of at least 10 mmHg was considered as IAD. At baseline, the systolic blood pressure (SBP) l-r and diastolic blood pressure (DBP) l-r were similar in three age groups. One-arm exercise induced a marked decrease in DBP in the exercised arm, and then increased the prevalence of DBP l-r and dIAD in the three age groups in an age-dependent manner. The prevalence of dIAD increased from the baseline of zero to 85% at 0 min in young, 37% in middle-aged, and 30% in senior groups. One-arm exercise did not significantly alter the prevalence of SBP l-r and systolic IAD in the three groups. A reverse correlation was found between the DBP l-r 0 and ages (r=-0.359, Parm exercise in healthy adults.
Use of Saliva Biomarkers to Monitor Efficacy of Vitamin C in Exercise-Induced Oxidative Stress

Directory of Open Access Journals (Sweden)

Levi W. Evans

2017-01-01

Full Text Available Saliva is easily obtainable for medical research and requires little effort or training for collection. Because saliva contains a variety of biological compounds, including vitamin C, malondialdehyde, amylase, and proteomes, it has been successfully used as a biospecimen for the reflection of health status. A popular topic of discussion in medical research is the potential association between oxidative stress and negative outcomes. Systemic biomarkers that represent oxidative stress can be found in saliva. It is unclear, however, if saliva is an accurate biospecimen as is blood and/or plasma. Exercise can induce oxidative stress, resulting in a trend of antioxidant supplementation to combat its assumed detriments. Vitamin C is a popular antioxidant supplement in the realm of sports and exercise. One potential avenue for evaluating exercise induced oxidative stress is through assessment of biomarkers like vitamin C and malondialdehyde in saliva. At present, limited research has been done in this area. The current state of research involving exercise-induced oxidative stress, salivary biomarkers, and vitamin C supplementation is reviewed in this article.
Obesity and exercise-induced ectopic ventricular arrhythmias in apparently healthy middle aged adults.

Science.gov (United States)

Sabbag, Avi; Sidi, Yechezkel; Kivity, Shaye; Beinart, Roy; Glikson, Michael; Segev, Shlomo; Goldenberg, Ilan; Maor, Elad

2016-03-01

Obesity and overweight are strongly associated with cardiovascular morbidity and mortality. However, there are limited data on the association between excess weight and the risk of ectopic ventricular activity. We investigated the association between body mass index (BMI) and the risk for ectopic ventricular activity (defined as multiple ventricular premature beats (≥3), ventricular bigeminy, nonsustained ventricular tachycardia or sustained ventricular tachycardia) during exercise stress testing among 22,516 apparently healthy men and women who attended periodic health screening examinations between the years 2000 and 2014. All subjects had completed maximal exercise stress testing annually according to the Bruce protocol. Subjects were divided at baseline into three groups: normal weight (BMI ≥ 18.5 kg/m(2) andexercise-induced ectopic ventricular activity arrhythmias was highest among obese subjects, intermediate among overweight subjects and lowest among subjects with normal weight (3.4%, 2.7% and 2.2% respectively; p exercise compared with subjects with normal weight (p = 0.005), and that each 1 kg/m(2) increase in BMI was associated with a significant 4% (p = 0.002) increased adjusted risk for exercise-induced ventricular arrhythmias. Obesity is independently associated with increased likelihood of ectopic ventricular arrhythmia during exercise. © The European Society of Cardiology 2015.
Ampk phosphorylation of Ulk1 is required for targeting of mitochondria to lysosomes in exercise-induced mitophagy.

Science.gov (United States)

Laker, Rhianna C; Drake, Joshua C; Wilson, Rebecca J; Lira, Vitor A; Lewellen, Bevan M; Ryall, Karen A; Fisher, Carleigh C; Zhang, Mei; Saucerman, Jeffrey J; Goodyear, Laurie J; Kundu, Mondira; Yan, Zhen

2017-09-15

Mitochondrial health is critical for skeletal muscle function and is improved by exercise training through both mitochondrial biogenesis and removal of damaged/dysfunctional mitochondria via mitophagy. The mechanisms underlying exercise-induced mitophagy have not been fully elucidated. Here, we show that acute treadmill running in mice causes mitochondrial oxidative stress at 3-12 h and mitophagy at 6 h post-exercise in skeletal muscle. These changes were monitored using a novel fluorescent reporter gene, pMitoTimer, that allows assessment of mitochondrial oxidative stress and mitophagy in vivo, and were preceded by increased phosphorylation of AMP activated protein kinase (Ampk) at tyrosine 172 and of unc-51 like autophagy activating kinase 1 (Ulk1) at serine 555. Using mice expressing dominant negative and constitutively active Ampk in skeletal muscle, we demonstrate that Ulk1 activation is dependent on Ampk. Furthermore, exercise-induced metabolic adaptation requires Ulk1. These findings provide direct evidence of exercise-induced mitophagy and demonstrate the importance of Ampk-Ulk1 signaling in skeletal muscle.Exercise is associated with biogenesis and removal of dysfunctional mitochondria. Here the authors use a mitochondrial reporter gene to demonstrate the occurrence of mitophagy following exercise in mice, and show this is dependent on AMPK and ULK1 signaling.
Influence of artistic gymnastics on iron nutritional status and exercise-induced hemolysis in female athletes.

Science.gov (United States)

Sureira, Thaiz Mattos; Amancio, Olga Silverio; Pellegrini Braga, Josefina Aparecida

2012-08-01

This study evaluates the relationship between body iron losses and gains in artistic gymnastics female athletes. It shows that despite the low iron intake and exercise-induced hemolysis, iron deficiency or iron-deficiency anemia does not occur, but partial changes in the hematological profile do. The hypothesis that gymnasts' nutritional behavior contributes to anemia, which may be aggravated by exercise-induced hemolysis, led to this cross-sectional study, conducted with 43 female artistic gymnasts 6-16 yr old. The control group was formed by 40 nontraining girls, paired by age. Hemogram, serum iron, ferritin, soluble transferrin receptor, haptoglobin, total and fractional bilirubin, Type I urine, and parasitologic and occult fecal blood tests were evaluated. The athletes presented mean hematimetric and serum iron values (p = .020) higher than those of the control group. The bilirubin result discarded any hemolytic alteration in both groups. The haptoglobin results were lower in the athlete group (p = .002), confirming the incidence of exercise-induced hemolysis. Both groups presented low iron intake. The results suggest that artistic gymnastics practice leads to exercise-induced hemolysis and partially changes the hematological profile, although not causing iron deficiency or iron-deficiency anemia, even in the presence of low iron intake.
Immune-regulating effects of exercise on cigarette smoke-induced inflammation

Directory of Open Access Journals (Sweden)

Madani A

2018-04-01

Full Text Available Ashkan Madani,1 Katharina Alack,2 Manuel Jonas Richter,3,4 Karsten Krüger1 1Department of Exercise and Health, Institute of Sports Science, Leibniz University Hannover, Germany; 2Department of Sports Medicine, University of Giessen, Germany; 3Department of Internal Medicine, Justus Liebig University Giessen, Universities of Giessen and Marburg Lung Center (UGMLC, Germany; 4German Center for Lung Research (DZL, Giessen, Germany Abstract: Long-term cigarette smoking (LTCS represents an important risk factor for cardiac infarction and stroke and the central risk factor for the development of a bronchial carcinoma, smoking-associated interstitial lung fibrosis, and chronic obstructive pulmonary disease. The pathophysiologic development of these diseases is suggested to be promoted by chronic and progressive inflammation. Cigarette smoking induces repetitive inflammatory insults followed by a chronic and progressive activation of the immune system. In the pulmonary system of cigarette smokers, oxidative stress, cellular damage, and a chronic activation of pattern recognition receptors are described which are followed by the translocation of the NF-kB, the release of pro-inflammatory cytokines, chemokines, matrix metalloproteases, and damage-associated molecular patterns. In parallel, smoke pollutants cross directly through the alveolus–capillary interface and spread through the systemic bloodstream targeting different organs. Consequently, LTCS induces a systemic low-grade inflammation and increased oxidative stress in the vascular system. In blood, these processes promote an increased coagulation and endothelial dysfunction. In muscle tissue, inflammatory processes activate catabolic signaling pathways followed by muscle wasting and sarcopenia. In brain, several characteristics of neuroinflammation were described. Regular exercise training has been shown to be an effective nonpharmacological treatment strategy in smoke-induced pulmonary diseases
Magnetic reconnection and precursor effect in coaxial discharge

International Nuclear Information System (INIS)

Masoud, M.M.; Soliman, H.M.; El-Khalafawy, T.A.

1988-01-01

A precursor pulse was observed ahead of the plasma sheath produced by a coaxial electrode discharge system. The velocity of the precursor pulse was 4x10 7 cmS -1 and the velocity of the plasma sheath was 6x10 6 cmS -1 . The precursor pulse was unaffected when an axial magnetic field of 6 K.G. was applied to the propagation chamber, while the plasma sheath velocity increased and downstream structure were changed. The precursor pulse was split, sometimes, into two or more peaks, had the same shape and structure of the original one. The rest gas was heated up to 20 e.V. when the precursor pulse was destructed. The precursor pulse propagation mechanism and parameters showed that it had a solitary wave structure and behaviour. A reversed magnetic field was detected, when the plasma sheath had diamagnetic properties, where magnetic reconnection took place. Magnetic reconnection was responsible for energy transfiguration and wave generation. This was due to acceleration mechanism of charged particles occurred by the induced electric field at the moment of magnetic reconnection. The detected induced electric field had a high field intensity and fast rise time pulse. Several instabilities were referred to magnetic reconnection and the precursor pulse observed was a result of such instabilities
Exercise training attenuated chronic cigarette smoking-induced up-regulation of FIZZ1/RELMα in lung of rats.

Science.gov (United States)

Ma, Wan-li; Cai, Peng-cheng; Xiong, Xian-zhi; Ye, Hong

2013-02-01

FIZZ/RELM is a new gene family named "found in inflammatory zone" (FIZZ) or "resistin-like molecule" (RELM). FIZZ1/RELMα is specifically expressed in lung tissue and associated with pulmonary inflammation. Chronic cigarette smoking up-regulates FIZZ1/RELMα expression in rat lung tissues, the mechanism of which is related to cigarette smoking-induced airway hyperresponsiveness. To investigate the effect of exercise training on chronic cigarette smoking-induced airway hyperresponsiveness and up-regulation of FIZZ1/RELMα, rat chronic cigarette smoking model was established. The rats were treated with regular exercise training and their airway responsiveness was measured. Hematoxylin and eosin (HE) staining, immunohistochemistry and in situ hybridization of lung tissues were performed to detect the expression of FIZZ1/RELMα. Results revealed that proper exercise training decreased airway hyperresponsiveness and pulmonary inflammation in rat chronic cigarette smoking model. Cigarette smoking increased the mRNA and protein levels of FIZZ1/RELMα, which were reversed by the proper exercise. It is concluded that proper exercise training prevents up-regulation of FIZZ1/RELMα induced by cigarette smoking, which may be involved in the mechanism of proper exercise training modulating airway hyperresponsiveness.
Significance of exercise-induced ST segment depression in patients with myocardial infarction involving the left circumflex artery. Evaluation by exercise thallium-201 myocardial single photon emission computed tomography

International Nuclear Information System (INIS)

Koitabashi, Norimichi; Toyama, Takuji; Hoshizaki, Hiroshi

2000-01-01

The significance of exercise-induced ST segment depression in patients with left circumflex artery involvement was investigated by comparing exercise electrocardiography with exercise thallium-201 single photon emission computed tomography (Tl-SPECT) and the wall motion estimated by left ventriculography. Tl-SPECT and exercise electrocardiography were simultaneously performed in 51 patients with left circumflex artery involvement (angina pectoris 30, myocardial infarction 21). In patients with myocardial infarction, exercise-induced ST depression was frequently found in the V 2 , V 3 and V 4 leads. In patients with angina pectoris, ST depression was frequently found in the II, III, aV F , V 5 and V 6 leads. There was no obvious difference in the leads of ST depression in patients with myocardial infarction with ischemia and without ischemia on Tl-SPECT images. In patients with myocardial infarction, the lateral wall motion of the infarcted area evaluated by left ventriculography was more significantly impaired in the patients with ST depression than without ST depression (p<0.01). Exercise-induced ST depression in the precordial leads possibly reflects wall motion abnormality rather than ischemia in the lateral infarcted myocardium. (author)
Treadmill exercise alleviates stress-induced impairment of social interaction through 5-hydroxytryptamine 1A receptor activation in rats.

Science.gov (United States)

Kim, Tae-Woon; Lim, Baek-Vin; Kim, Kijeong; Seo, Jin-Hee; Kim, Chang-Ju

2015-08-01

Brain-derived neurotrophic factor (BDNF) and its receptors tyrosine kinase B (trkB), and cyclic adenosine monophosphate response element binding protein (CREB) have been suggested as the neurobiological risk factors causing depressive disorder. Serotonin (5-hydroxytryptamine, 5-HT) plays an important role in the pathogenesis of depression. We in-vestigated the effect of treadmill exercise on social interaction in relation with BDNF and 5-HT expressions following stress in rats. Stress was induced by applying inescapable 0.2 mA electric foot shock to the rats for 7 days. The rats in the exercise groups were forced to run on a motorized treadmill for 30 min once a day for 4 weeks. Social interaction test and western blot for BDNF, TrkB, pCREB, and 5-HT1A in the hippocampus were performed. The results indicate that the spend time with unfamiliar partner was decreased by stress, in contrast, treadmill exercise increased the spending time in the stress-induced rats. Expressions of BDNF, TrkB, and pCREB were decreased by stress, in contrast, treadmill exercise enhanced expressions of BDNF, TrkB, and pCREB in the stress-induced rats. In addition, 5-HT1A receptor expression was de-creased by stress, in contrast, treadmill exercise enhanced 5-HT1A expression in the stress-induced rats. In the present study, treadmill exercise alleviated stress-induced social interaction impairment through enhancing hippocampal plasticity and serotonergic function in the hippocampus. These effects of treadmill exercise are achieved through 5-HT1A receptor activation.
Green Tea Catechin Consumption Enhances Exercise-Induced Abdominal Fat Loss

Science.gov (United States)

Aim: This study evaluated the influence of a green tea catechin beverage on body composition and fat distribution in overweight and obese adults during exercised-induced weight loss. Methods: Participants (N=132) were randomly assigned to receive a 500 mL beverage containing approximately 625 mg of...
AMP-activated protein kinase controls exercise training- and AICAR-induced increases in SIRT3 and MnSOD

DEFF Research Database (Denmark)

Brandauer, Josef; Andersen, Marianne A; Kellezi, Holti

2015-01-01

, the acetylation status of SIRT3 target lysine residues on MnSOD (K122) or oligomycin-sensitivity conferring protein (OSCP; K139) was not altered in either mouse or human skeletal muscle in response to acute exercise. We propose an important role for AMPK in regulating mitochondrial function and ROS handling......The mitochondrial protein deacetylase sirtuin (SIRT) 3 may mediate exercise training-induced increases in mitochondrial biogenesis and improvements in reactive oxygen species (ROS) handling. We determined the requirement of AMP-activated protein kinase (AMPK) for exercise training-induced increases...... in skeletal muscle abundance of SIRT3 and other mitochondrial proteins. Exercise training for 6.5 weeks increased SIRT3 (p
The TRPC1 Ca2+-permeable channel inhibits exercise-induced protection against high-fat diet-induced obesity and type II diabetes.

Science.gov (United States)

Krout, Danielle; Schaar, Anne; Sun, Yuyang; Sukumaran, Pramod; Roemmich, James N; Singh, Brij B; Claycombe-Larson, Kate J

2017-12-15

The transient receptor potential canonical channel-1 (TRPC1) is a Ca 2+ -permeable channel found in key metabolic organs and tissues, including the hypothalamus, adipose tissue, and skeletal muscle. Loss of TRPC1 may alter the regulation of cellular energy metabolism resulting in insulin resistance thereby leading to diabetes. Exercise reduces insulin resistance, but it is not known whether TRPC1 is involved in exercise-induced insulin sensitivity. The role of TRPC1 in adiposity and obesity-associated metabolic diseases has not yet been determined. Our results show that TRPC1 functions as a major Ca 2+ entry channel in adipocytes. We have also shown that fat mass and fasting glucose concentrations were lower in TRPC1 KO mice that were fed a high-fat (HF) (45% fat) diet and exercised as compared with WT mice fed a HF diet and exercised. Adipocyte numbers were decreased in both subcutaneous and visceral adipose tissue of TRPC1 KO mice fed a HF diet and exercised. Finally, autophagy markers were decreased and apoptosis markers increased in TRPC1 KO mice fed a HF diet and exercised. Overall, these findings suggest that TRPC1 plays an important role in the regulation of adiposity via autophagy and apoptosis and that TRPC1 inhibits the positive effect of exercise on type II diabetes risk under a HF diet-induced obesity environment.
Deletion of TLX and social isolation impairs exercise-induced neurogenesis in the adolescent hippocampus.

Science.gov (United States)

Kozareva, Danka A; O'Leary, Olivia F; Cryan, John F; Nolan, Yvonne M

2018-01-01

Adolescence is a sensitive period of neurodevelopment during which life experiences can have profound effects on the brain. Hippocampal neurogenesis, the neurodevelopmental process of generating functional new neurons from neural stem cells, occurs throughout the lifespan and has been shown to play a role in learning, memory and in mood regulation. In adulthood it is influenced by extrinsic environmental factors such as exercise and stress. Intrinsic factors that regulate hippocampal neurogenesis include the orphan nuclear receptor TLX (Nr2e1) which is primarily expressed in the neurogenic niches of the brain. While mechanisms regulating adult hippocampal neurogenesis have been widely studied, less is known on how hippocampal neurogenesis is affected during adolescence. The aim of this study was to investigate the influence of both TLX and isolation stress on exercise-induced increases in neurogenesis in running and sedentary conditions during adolescence. Single- (isolation stress) wild type and Nr2e1 -/- mice or pair-housed wild type mice were housed in sedentary conditions or allowed free access to running wheels for 3 weeks during adolescence. A reduction of neuronal survival was evident in mice lacking TLX, and exercise did not increase hippocampal neurogenesis in these Nr2e1 -/- mice. This suggests that TLX is necessary for the pro-neurogenic effects of exercise during adolescence. Interestingly, although social isolation during adolescence did not affect hippocampal neurogenesis, it prevented an exercise-induced increase in neurogenesis in the ventral hippocampus. Together these data demonstrate the importance of intrinsic and extrinsic factors in promoting an exercise-induced increase in neurogenesis at this key point in life. © 2017 Wiley Periodicals, Inc.
Exercise-induced albuminuria is related to metabolic syndrome.

Science.gov (United States)

Greenberg, Sharon; Shenhar-Tsarfaty, Shani; Rogowski, Ori; Shapira, Itzhak; Zeltser, David; Weinstein, Talia; Lahav, Dror; Vered, Jaffa; Tovia-Brodie, Oholi; Arbel, Yaron; Berliner, Shlomo; Milwidsky, Assi

2016-06-01

Microalbuminuria (MA) is a known marker for endothelial dysfunction and future cardiovascular events. Exercise-induced albuminuria (EiA) may precede the appearance of MA. Associations between EiA and metabolic syndrome (MS) have not been assessed so far. Our aim was to investigate this association in a large sample of apparently healthy individuals with no baseline albuminuria. This was a cross-sectional study of 2,027 adults with no overt cardiovascular diseases who took part in a health survey program and had no baseline MA. Diagnosis of MS was based on harmonized criteria. All patients underwent an exercise test (Bruce protocol), and urinary albumin was measured before and after the examination. Urinary albumin-to-creatinine ratio (ACR) values before and after exercise were 0.40 (0.21-0.89) and 1.06 (0.43-2.69) mg/g for median (interquartile range) respectively. A total of 394 (20%) subjects had EiA; ACR rose from normal rest values (0.79 mg/g) to 52.28 mg/g after exercise (P metabolic equivalents (P < 0.001), higher baseline blood pressure (P < 0.001), and higher levels of fasting plasma glucose, triglycerides, and body mass index (P < 0.001). Multivariate binary logistic regression model showed that subjects with MS were 98% more likely to have EiA (95% confidence interval: 1.13-3.46, P = 0.016). In conclusion, EiA in the absence of baseline MA is independently related to MS. Copyright © 2016 the American Physiological Society.

Hyper-hippocampal glycogen induced by glycogen loading with exhaustive exercise.

Science.gov (United States)

Soya, Mariko; Matsui, Takashi; Shima, Takeru; Jesmin, Subrina; Omi, Naomi; Soya, Hideaki

2018-01-19

Glycogen loading (GL), a well-known type of sports conditioning, in combination with exercise and a high carbohydrate diet (HCD) for 1 week enhances individual endurance capacity through muscle glycogen supercompensation. This exercise-diet combination is necessary for successful GL. Glycogen in the brain contributes to hippocampus-related memory functions and endurance capacity. Although the effect of HCD on the brain remains unknown, brain supercompensation occurs following exhaustive exercise (EE), a component of GL. We thus employed a rat model of GL and examined whether GL increases glycogen levels in the brain as well as in muscle, and found that GL increased glycogen levels in the hippocampus and hypothalamus, as well as in muscle. We further explored the essential components of GL (exercise and/or diet conditions) to establish a minimal model of GL focusing on the brain. Exercise, rather than a HCD, was found to be crucial for GL-induced hyper-glycogen in muscle, the hippocampus and the hypothalamus. Moreover, EE was essential for hyper-glycogen only in the hippocampus even without HCD. Here we propose the EE component of GL without HCD as a condition that enhances brain glycogen stores especially in the hippocampus, implicating a physiological strategy to enhance hippocampal functions.
Occlusion of blood flow attenuates exercise-induced hypoalgesia in the occluded limb of healthy adults.

Science.gov (United States)

Jones, Matthew D; Taylor, Janet L; Barry, Benjamin K

2017-05-01

Animal studies have demonstrated an important role of peripheral mechanisms as contributors to exercise-induced hypoalgesia (EIH). Whether these same mechanisms contribute to EIH in humans is not known. In the current study, pain thresholds were assessed in healthy volunteers ( n = 36) before and after 5 min of high-intensity leg cycling exercise and an equivalent period of quiet rest. Pressure pain thresholds (PPTs) were assessed over the rectus femoris muscle of one leg and first dorsal interosseous muscles (FDIs) of both arms. Blood flow to one arm was occluded by a cuff throughout the 5-min period of exercise (or rest) and postexercise (or rest) assessments. Ratings of pain intensity and pain unpleasantness during occlusion were also measured. Pain ratings during occlusion increased over time (range, 1.5 to 3.5/10, all d > 0.63, P exercise conditions ( d 0.4). PPTs at all sites were unchanged following rest (range, -1.3% to +0.9%, all d 0.51). Consistent with EIH, exercise significantly increased PPT at the leg (+29%, d = 0.69, P exercise attenuates EIH, suggesting that peripheral factors contribute to EIH in healthy adults. NEW & NOTEWORTHY This is the first demonstration in humans that a factor carried by the circulation and acting at the periphery is important for exercise-induced hypoalgesia. Further understanding of this mechanism may provide new insight to pain relief with exercise as well as potential interactions between analgesic medications and exercise. Copyright © 2017 the American Physiological Society.
Possible in vivo tolerance of human polymorphonuclear neutrophil to low-grade exercise-induced endotoxaemia

Directory of Open Access Journals (Sweden)

G. Camus

1998-01-01

Full Text Available To address the question of whether translocation of bacterial lipopolysaccharide (LPS into the blood could be involved in the process of exercise-induced polymorphonuclear neutrophil (PMN activation, 12 healthy male subjects who took part in a sprint triathlon (1.5 km river swim, 40 km bicycle race, 10 km road race were studied. While there was no detectable amount of endotoxin in the blood samples drawn at rest, exercise was followed by the appearance of circulating endotoxin molecules at the end of competition in four subjects, and after one and 24 h recovery in three and seven athletes, respectively. The concentrations of plasma granulocyte myeloperoxidase ([MPO], were significantly higher immediately after exercise and one hour later than baseline values (P<0.001. This variable returned to pre-race levels the day after exercise, despite the presence of detectable amounts of LPS, at that time, in seven athletes. The absence of significant correlation (r=0.26;P=0.383 and temporal association between [MPO]and plasma endotoxin levels led us to conclude that endotoxaemia was not involved in the process of exercise-induced PMN degranulation observed in our subjects.
Effect of Locomotor Respiratory Coupling Induced by Cortical Oxygenated Hemoglobin Levels During Cycle Ergometer Exercise of Light Intensity.

Science.gov (United States)

Oyanagi, Keiichi; Tsubaki, Atsuhiro; Yasufuku, Yuichi; Takai, Haruna; Kera, Takeshi; Tamaki, Akira; Iwata, Kentaro; Onishi, Hideaki

This study aimed to clarify the effects of locomotor-respiratory coupling (LRC) induced by light load cycle ergometer exercise on oxygenated hemoglobin (O2Hb) in the dorsolateral prefrontal cortex (DLPFC), supplementary motor area (SMA), and sensorimotor cortex (SMC). The participants were 15 young healthy adults (9 men and 6 women, mean age: 23.1 ± 1.8 (SEM) years). We conducted a task in both LRC-inducing and LRC-non-inducing conditions for all participants. O2Hb was measured using near-infrared spectroscopy. The LRC frequency ratio during induction was 2:1; pedaling rate, 50 rpm; and intensity of load, 30 % peak volume of oxygen uptake. The test protocol included a 3-min rest prior to exercise, steady loading motion for 10 min, and 10-min rest post exercise (a total of 23 min). In the measurement of O2Hb, we focused on the DLPFC, SMA, and SMC. The LRC frequency was significantly higher in the LRC-inducing condition (p < 0.05). O2Hb during exercise was significantly lower in the DLPFC and SMA, under the LRC-inducing condition (p < 0.05). The study revealed that even light load could induce LRC and that O2Hb in the DLPFC and SMA decreases during exercise via LRC induction.
Effects of contraction duration on low-frequency fatigue in voluntary and electrically induced exercise of quadriceps muscle in humans.

Science.gov (United States)

Ratkevicius, A; Skurvydas, A; Povilonis, E; Quistorff, B; Lexell, J

1998-04-01

The aims of this study were to investigate if low-frequency fatigue (LFF) dependent on the duration of repeated muscle contractions and to compare LFF in voluntary and electrically induced exercise. Male subjects performed three 9-min periods of repeated isometric knee extensions at 40% maximal voluntary contraction with contraction plus relaxation periods of 30 plus 60 s, 15 plus 30 s and 5 plus 10 s in protocols 1, 2 and 3, respectively. The same exercise protocols were repeated using feedback-controlled electrical stimulation at 40% maximal tetanic torque. Before and 15 min after each exercise period, knee extension torque at 1, 7, 10, 15, 20, 50 and 100 Hz was assessed. During voluntary exercise, electromyogram root mean square (EMGrms) of the vastus lateralis muscle was evaluated. The 20-Hz torque:100-Hz torque (20:100 Hz torque) ratio was reduced more after electrically induced than after voluntary exercise (P exercise, the decrease in 20:100 Hz torque ratio was gradually (P exercise, the decrease in 20:100 Hz torque ratio and the increase in EMGrms were greater in protocol 1 (P exercise and that the electrically induced exercise produced a more pronounced LFF compared to voluntary exercise of submaximal intensity. It is suggested that compensatory recruitment of faster-contracting motor units is an additional factor affecting the severity of LFF during voluntary exercise.
Exercise Prevents Diet-Induced Cellular Senescence in Adipose Tissue.

Science.gov (United States)

Schafer, Marissa J; White, Thomas A; Evans, Glenda; Tonne, Jason M; Verzosa, Grace C; Stout, Michael B; Mazula, Daniel L; Palmer, Allyson K; Baker, Darren J; Jensen, Michael D; Torbenson, Michael S; Miller, Jordan D; Ikeda, Yasuhiro; Tchkonia, Tamara; van Deursen, Jan M; Kirkland, James L; LeBrasseur, Nathan K

2016-06-01

Considerable evidence implicates cellular senescence in the biology of aging and chronic disease. Diet and exercise are determinants of healthy aging; however, the extent to which they affect the behavior and accretion of senescent cells within distinct tissues is not clear. Here we tested the hypothesis that exercise prevents premature senescent cell accumulation and systemic metabolic dysfunction induced by a fast-food diet (FFD). Using transgenic mice that express EGFP in response to activation of the senescence-associated p16(INK4a) promoter, we demonstrate that FFD consumption causes deleterious changes in body weight and composition as well as in measures of physical, cardiac, and metabolic health. The harmful effects of the FFD were associated with dramatic increases in several markers of senescence, including p16, EGFP, senescence-associated β-galactosidase, and the senescence-associated secretory phenotype (SASP) specifically in visceral adipose tissue. We show that exercise prevents the accumulation of senescent cells and the expression of the SASP while nullifying the damaging effects of the FFD on parameters of health. We also demonstrate that exercise initiated after long-term FFD feeding reduces senescent phenotype markers in visceral adipose tissue while attenuating physical impairments, suggesting that exercise may provide restorative benefit by mitigating accrued senescent burden. These findings highlight a novel mechanism by which exercise mediates its beneficial effects and reinforces the effect of modifiable lifestyle choices on health span. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.
ABNORMAL PLASMA NORADRENALINE RESPONSE AND EXERCISE INDUCED ALBUMINURIA IN TYPE-1 (INSULIN-DEPENDENT) DIABETES-MELLITUS

NARCIS (Netherlands)

HOOGENBERG, K; DULLAART, RPF

1992-01-01

Submaximal exercise provokes an abnormal elevation in albuminuria in type 1 (insulin-dependent) diabetes mellitus. Plasma catecholamines might be involved in this phenomenon by a renal vasoconstrictive effect. Twelve healthy subjects (Controls: albuminuria It is concluded that the exercise-induced
The signaling mechanisms of hippocampal endoplasmic reticulum stress affecting neuronal plasticity-related protein levels in high fat diet-induced obese rats and the regulation of aerobic exercise.

Science.gov (United States)

Cai, Ming; Wang, Hong; Li, Jing-Jing; Zhang, Yun-Li; Xin, Lei; Li, Feng; Lou, Shu-Jie

2016-10-01

significantly decreased proBDNF-the precursor of mature BDNF, but also attenuated p38/ERK-CREB signaling pathways and activated NLRP3-IL-1β pathways in obese rats. These results were associated with reduced BDNF and SYN protein production. However, these adverse changes were obviously reversed by aerobic exercise intervention through activating the Nrf2-HO-1 pathways. These results suggest that dietary obesity could induce hippocampal ERS in male SD rats, and excessive hippocampal ERS plays a critical role in decreasing the levels of BDNF and SYN. Moreover, aerobic exercise could activate hippocampal Nrf2 and HO-1 to relieve ERS and heighten BDNF and SYN production in obese rats. Copyright © 2016 Elsevier Inc. All rights reserved.
Forced running exercise attenuates hippocampal neurogenesis impairment and the neurocognitive deficits induced by whole-brain irradiation via the BDNF-mediated pathway

International Nuclear Information System (INIS)

Ji, Jian-feng; Ji, Sheng-jun; Sun, Rui; Li, Kun; Zhang, Yuan; Zhang, Li-yuan; Tian, Ye

2014-01-01

Highlights: •Forced exercise can ameliorate WBI induced cognitive impairment in our rat model. •Mature BDNF plays an important role in the effects of forced exercise. •Exercise may be a possible treatment of the radiation-induced cognitive impairment. -- Abstract: Cranial radiotherapy induces progressive and debilitating cognitive deficits, particularly in long-term cancer survivors, which may in part be caused by the reduction of hippocampal neurogenesis. Previous studies suggested that voluntary exercise can reduce the cognitive impairment caused by radiation therapy. However, there is no study on the effect of forced wheel exercise and little is known about the molecular mechanisms mediating the effect of exercise. In the present study, we investigated whether the forced running exercise after irradiation had the protective effects of the radiation-induced cognitive impairment. Sixty-four Male Sprague–Dawley rats received a single dose of 20 Gy or sham whole-brain irradiation (WBI), behavioral test was evaluated using open field test and Morris water maze at 2 months after irradiation. Half of the rats accepted a 3-week forced running exercise before the behavior detection. Immunofluorescence was used to evaluate the changes in hippocampal neurogenesis and Western blotting was used to assess changes in the levels of mature brain-derived neurotrophic factor (BDNF), phosphorylated tyrosine receptor kinase B (TrkB) receptor, protein kinase B (Akt), extracellular signal-regulated kinase (ERK), calcium-calmodulin dependent kinase (CaMKII), cAMP-calcium response element binding protein (CREB) in the BDNF–pCREB signaling. We found forced running exercise significantly prevented radiation-induced cognitive deficits, ameliorated the impairment of hippocampal neurogenesis and attenuated the down-regulation of these proteins. Moreover, exercise also increased behavioral performance, hippocampal neurogenesis and elevated BDNF–pCREB signaling in non
Forced running exercise attenuates hippocampal neurogenesis impairment and the neurocognitive deficits induced by whole-brain irradiation via the BDNF-mediated pathway

Energy Technology Data Exchange (ETDEWEB)

Ji, Jian-feng; Ji, Sheng-jun; Sun, Rui; Li, Kun; Zhang, Yuan; Zhang, Li-yuan; Tian, Ye, E-mail: dryetian@hotmail.com

2014-01-10

Highlights: •Forced exercise can ameliorate WBI induced cognitive impairment in our rat model. •Mature BDNF plays an important role in the effects of forced exercise. •Exercise may be a possible treatment of the radiation-induced cognitive impairment. -- Abstract: Cranial radiotherapy induces progressive and debilitating cognitive deficits, particularly in long-term cancer survivors, which may in part be caused by the reduction of hippocampal neurogenesis. Previous studies suggested that voluntary exercise can reduce the cognitive impairment caused by radiation therapy. However, there is no study on the effect of forced wheel exercise and little is known about the molecular mechanisms mediating the effect of exercise. In the present study, we investigated whether the forced running exercise after irradiation had the protective effects of the radiation-induced cognitive impairment. Sixty-four Male Sprague–Dawley rats received a single dose of 20 Gy or sham whole-brain irradiation (WBI), behavioral test was evaluated using open field test and Morris water maze at 2 months after irradiation. Half of the rats accepted a 3-week forced running exercise before the behavior detection. Immunofluorescence was used to evaluate the changes in hippocampal neurogenesis and Western blotting was used to assess changes in the levels of mature brain-derived neurotrophic factor (BDNF), phosphorylated tyrosine receptor kinase B (TrkB) receptor, protein kinase B (Akt), extracellular signal-regulated kinase (ERK), calcium-calmodulin dependent kinase (CaMKII), cAMP-calcium response element binding protein (CREB) in the BDNF–pCREB signaling. We found forced running exercise significantly prevented radiation-induced cognitive deficits, ameliorated the impairment of hippocampal neurogenesis and attenuated the down-regulation of these proteins. Moreover, exercise also increased behavioral performance, hippocampal neurogenesis and elevated BDNF–pCREB signaling in non
Endurance training increases exercise-induced prostacyclin release in young, healthy men--relationship with VO2max.

Science.gov (United States)

Zoladz, Jerzy A; Majerczak, Joanna; Duda, Krzysztof; Chłopicki, Stefan

2010-01-01

In the present study, we evaluated the effect of 5 weeks of moderate-intensity endurance training on the basal and exercise-induced systemic release of prostacyclin (PGI(2)), as assessed by plasma 6-keto-PGF(1 alpha) concentration. Twelve physically active young men with the following characteristics participated in this study (the mean +/- SD): age, 22.7 +/- 2.0 years; body mass, 76.8 +/- 8.9 kg; BMI, 23.48 +/- 2.17 kg x m(-2); and maximal oxygen uptake (VO(2 max)), 46.1 +/- 4.0 ml x kg(-1) x min(-1). Plasma 6-keto-PGF(1 alpha) concentrations were measured in venous blood samples taken prior to the exercise and at exhaustion (at VO(2 max)) before and after completing the training protocol. On average, the training resulted in a significant increase in VO(2 max) (p = 0.03), power output at VO(2 max) (p = 0.001) and a significant increase (p = 0.05) in the net-exercise-induced increase in plasma 6-keto-PGF(1 alpha) concentration (Delta 6-keto-PGF(1 alpha) i.e., the difference between the end-exercise and pre-exercise 6-keto-PGF(1 alpha) concentrations). No effect of training on the basal PGI(2) concentration was found. Interestingly, within the study sample (n = 12), two subgroups could be defined with a differential pattern of response with respect to Delta 6-keto-PGF(1 alpha) concentrations. In one subgroup (n = 7), a significant increase in Delta 6-keto-PGF(1 alpha) concentration after training was found (p < 0.02) (responders). This enhancement in the exercise-induced PGI(2) release was accompanied by a significant (p < 0.05) increase in VO(2 max) after training. In contrast, in another subgroup (n = 5), there was no observed effect of training on the Delta 6-keto-PGF(1 alpha) concentration and the VO(2 max) after training (non-responders). In both of these subgroups, training did not influence the basal PGI(2) concentration. In conclusion, the endurance training resulted in the adaptive augmentation of the systemic release of PGI(2) in response to exercise
Exercise Prevents Diaphragm Wasting Induced by Cigarette Smoke through Modulation of Antioxidant Genes and Metalloproteinases

Directory of Open Access Journals (Sweden)

Gracielle Vieira Ramos

2018-01-01

Full Text Available Background. The present study aimed to analyze the effects of physical training on an antioxidant canonical pathway and metalloproteinases activity in diaphragm muscle in a model of cigarette smoke-induced chronic obstructive pulmonary disease (COPD. Methods. Male mice were randomized into control, smoke, exercise, and exercise + smoke groups, which were maintained in trial period of 24 weeks. Gene expression of kelch-like ECH-associated protein 1; nuclear factor erythroid-2 like 2; and heme-oxygenase1 by polymerase chain reaction was performed. Metalloproteinases 2 and 9 activities were analyzed by zymography. Exercise capacity was evaluated by treadmill exercise test before and after the protocol. Results. Aerobic training inhibited diaphragm muscle wasting induced by cigarette smoke exposure. This inhibition was associated with improved aerobic capacity in those animals that were submitted to 24 weeks of aerobic training, when compared to the control and smoke groups, which were not submitted to training. The aerobic training also downregulated the increase of matrix metalloproteinases (MMP-2 and MMP-9 and upregulated antioxidant genes, such as nuclear factor erythroid-2 like 2 (NRF2 and heme-oxygenase1 (HMOX1, in exercise + smoke group compared to smoke group. Conclusions. Treadmill aerobic training protects diaphragm muscle wasting induced by cigarette smoke exposure involving upregulation of antioxidant genes and downregulation of matrix metalloproteinases.
The basic chemistry of exercise-induced DNA oxidation: oxidative damage, redox signalling and their interplay

Directory of Open Access Journals (Sweden)

James Nathan Cobley

2015-06-01

Full Text Available Acute exercise increases reactive oxygen and nitrogen species generation. This phenomenon is associated with two major outcomes: (1 redox signalling and (2 macromolecule damage. Mechanistic knowledge of how exercise-induced redox signalling and macromolecule damage are interlinked is limited. This review focuses on the interplay between exercise-induced redox signalling and DNA damage, using hydroxyl radical (·OH and hydrogen peroxide (H2O2 as exemplars. It is postulated that the biological fate of H2O2 links the two processes and thus represents a bifurcation point between redox signalling and damage. Indeed, H2O2 can participate in two electron signalling reactions but its diffusion and chemical properties permit DNA oxidation following reaction with transition metals and ·OH generation. It is also considered that the sensing of DNA oxidation by repair proteins constitutes a non-canonical redox signalling mechanism. Further layers of interaction are provided by the redox regulation of DNA repair proteins and their capacity to modulate intracellular H2O2 levels. Overall, exercise-induced redox signalling and DNA damage may be interlinked to a greater extent than was previously thought but this requires further investigation.
Transient left ventricular apical ballooning and exercise induced hypertension during treadmill exercise testing: is there a common hypersympathetic mechanism?

Directory of Open Access Journals (Sweden)

Oh Jae K

2008-07-01

Full Text Available Abstract Objective To describe two cases of Takotsubo like myocardial contractile pattern during exercise stress test secondary to hypertensive response. Background Treadmill exercise testing is known to cause sympathetic stimulation, leading to increased levels of catecholamine, resulting in alteration in vascular tone. Hypertensive response during exercise testing can cause abnormal consequences, resulting in false positive results. Cases We present the cases of two patients experiencing apical and basal akinesis during exercise stress echocardiography, in whom normal wall motion response was observed on subsequent pharmacologic stress testing. The first patient developed transient left ventricular (LV apical akinesis during exercise stress echocardiography. Due to high suspicion that this abnormality might be secondary to hypertensive response, pharmacologic stress testing was performed after three days, which was completely normal and showed no such wall motion abnormality. Qualitative assessment of myocardial perfusion using contrast was also performed, which showed good myocardial blood flow, indicating low probability for significant obstructive coronary artery disease. The second patient developed LV basal akinesis as a result of hypertensive response during exercise testing. Coronary angiogram was not performed in either patient due to low suspicion for coronary artery disease, and subsequently negative stress studies. Results Transient stress induced cardiomyopathy can develop secondary to hypertensive response during exercise stress testing. Conclusion These cases provide supporting evidence to the hyper-sympathetic theory of left ventricular ballooning syndrome.
Relation between exercise-induced ventricular arrhythmias and myocardial perfusion abnormalities in patients with intermediate pretest probability of coronary artery disease

International Nuclear Information System (INIS)

Elhendy, A.; Sozzi, F.B.; Van Domburg, R.T.; Bax, J.J.; Roelandt, J.R.T.C.

2000-01-01

We studied 302 patients (mean age 54±9 years, 152 men and 150 women) with intermediate pretest probability of CAD (range=0.25- 0.80, mean=0.43±0.20) by upright bicycle exercise stress test in conjunction with technetium-99m single-photon emission tomography (SPET) imaging. Exercise-induced VAs (frequent or complex premature ventricular contractions or ventricular tachycardia) occurred in 65 patients (22%). No significant difference was found between patients with and patient without VAs regarding the pretest probability of CAD (0.45±0.21 vs 0.43±0.20). Patients with exercise-induced VAs had a higher prevalence of perfusion abnormalities (52% vs 26%, P=0.002) and ischaemic electrocardiographic changes (31% vs 16%, P<0.05) compared to patients without VAs. A higher prevalence of perfusion abnormalities in patients with VAs was observed in both men (67% vs 35%, P<0.01) and women (38% vs 16%, P<0.05). However, the positive predictive value of exercise-induced VAs for the presence of myocardial perfusion abnormalities was higher in men than in women (67% vs 38%, P<0.05). The presence of abnormal myocardial perfusion was the only independent predictor of exercise-induced VAs (OR 2.2; 95% CI, 1.2-4.2) by multivariate analysis of clinical and stress test variables. It is concluded that in patients with intermediate pretest probability of CAD, exercise-induced VAs are predictive of a higher prevalence of myocardial perfusion abnormalities in both men and women. However, the positive predictive value of exercise-induced VAs for perfusion abnormalities is higher in men. Because of the underestimation of ischaemia by electrocardiographic changes, exercise-induced VAs should be interpreted as a marker of a higher probability of CAD. (orig./MG) (orig.)
Endurance exercise training induces fat depot-specific differences in basal autophagic activity

Energy Technology Data Exchange (ETDEWEB)

Tanaka, Goki; Kato, Hisashi; Izawa, Tetsuya, E-mail: tizawa@mail.doshisha.ac.jp

2015-10-23

autophagosome associated LC3-II in WAT. • Exercise-induced changes in p62 and ATG7 were WAT-type specific. • Exercise-induced basal autophagic activity shows fat depot-specific differences.
Endurance exercise training induces fat depot-specific differences in basal autophagic activity

International Nuclear Information System (INIS)

Tanaka, Goki; Kato, Hisashi; Izawa, Tetsuya

2015-01-01

autophagosome associated LC3-II in WAT. • Exercise-induced changes in p62 and ATG7 were WAT-type specific. • Exercise-induced basal autophagic activity shows fat depot-specific differences.
Exercise-induced asthma in a group of South African schoolchildren ...

African Journals Online (AJOL)

Objectives. The study was conducted to ascertain whether physical education teachers, using a peak flow meter, could reliably screen for exercise-induced asthma (EIA) in children during free running. Design, setting and subjects. The study was conducted using a convenience sample of male pupils between the ages of 12 ...
Impact of statin use on exercise-induced cardiac troponin elevations.

NARCIS (Netherlands)

Eijsvogels, T.M.H.; Januzzi, J.L., Jr.; Taylor, B.A.; Isaacs, S.K.; D'Hemecourt, P.; Zaleski, A.; Dyer, S.; Troyanos, C.; Weiner, R.B.; Thompson, P.D.; Baggish, A.L.

2014-01-01

Marathon running commonly causes a transient elevation of creatine kinase and cardiac troponin I (cTnI). The use of statins before marathon running exacerbates the release of creatine kinase from skeletal muscle, but the effect of statin use on exercise-induced cTnI release is unknown. We therefore
Exercise-induced laryngeal obstructions: prevalence and symptoms in the general public

DEFF Research Database (Denmark)

Christensen, Pernille Melia; Thomsen, S F; Rasmussen, N

2011-01-01

Respiratory difficulties caused by exercise-induced laryngeal obstructions (EILOs) are reported with increasing frequency. The aim of this study was to assess the prevalence and symptoms of EILOs and their relation to airway hyperresponsiveness (AHR). In total, 556 randomly selected youths...

Exercise-induced increase in glucose transport, GLUT-4, and VAMP-2 in plasma membrane from human muscle

DEFF Research Database (Denmark)

Kristiansen, S; Hargreaves, Mark; Richter, Erik

1996-01-01

contractions may induce trafficking of GLUT-4-containing vesicles via a mechanism similar to neurotransmitter release. Our results demonstrate for the first time exercise-induced translocation of GLUT-4 and VAMP-2 to the plasma membrane of human muscle and increased sarcolemmal glucose transport.......A major effect of muscle contractions is an increase in sarcolemmal glucose transport. We have used a recently developed technique to produce sarcolemmal giant vesicles from human muscle biopsy samples obtained before and after exercise. Six men exercised for 10 min at 50% maximal O2 uptake (Vo2max...
Alteration in gene expression in Nile tilapia (Oreochromis niloticus) juveniles submitted to fasting and refeeding.

Science.gov (United States)

One of the most important biological processes in living organisms that are affected by environmental fluctuations is growth, and the skeletal muscle growth in fish is dependent on proliferation and differentiation of myogenic precursor cells that are activated by Myogenic Regulatory Factors or inhi...
The effects of exercise-induced weight loss on appetite-related peptides and motivation to eat

DEFF Research Database (Denmark)

Martins, Cecilia; Kulseng, B; King, N A

2010-01-01

The magnitude of exercise-induced weight loss depends on the extent of compensatory responses. An increase in energy intake is likely to result from changes in the appetite control system toward an orexigenic environment; however, few studies have measured how exercise impacts on both orexigenic...
Exercise-Induced Anaphylaxis: A Case Report and Review of the Diagnosis and Treatment of a Rare but Potentially Life-Threatening Syndrome

Directory of Open Access Journals (Sweden)

Nathan T. Jaqua

2013-01-01

Full Text Available A 24-year-old male Marine with an uncomplicated medical history and a long history of strenuous, daily exercise presented to the emergency department after experiencing anaphylactic shock while running. Symptoms resolved following administration of intramuscular diphenhydramine, ranitidine, intravenous methylprednisolone, and intravenous fluids. On followup in the allergy clinic, a meticulous clinical history was obtained which elucidated a picture consistent with exercise-induced anaphylaxis. He had experienced diffuse pruritus and urticaria while exercising on multiple occasions over the last three years. His symptoms would usually increase as exercise continued. Prior to the first episode, he regularly exercised without symptoms. Exercise-induced anaphylaxis is a rare but potentially life-threatening syndrome that requires a careful clinical history and is a diagnosis of exclusion. Treatment is primarily exercise avoidance. Prophylactic mediations are inconsistently effective but are empirically used. Successful treatment with omalizumab was recently reported in a case of refractory exercise-induced anaphylaxis.
The Impact of Central and Peripheral Cyclooxygenase Enzyme Inhibition on Exercise-Induced Elevations in Core Body Temperature.

Science.gov (United States)

Veltmeijer, Matthijs T W; Veeneman, Dineke; Bongers, Coen C C W; Netea, Mihai G; van der Meer, Jos W; Eijsvogels, Thijs M H; Hopman, Maria T E

2017-05-01

Exercise increases core body temperature (T C ) due to metabolic heat production. However, the exercise-induced release of inflammatory cytokines including interleukin-6 (IL-6) may also contribute to the rise in T C by increasing the hypothalamic temperature set point. This study investigated whether the exercise-induced increase in T C is partly caused by an altered hypothalamic temperature set point. Fifteen healthy, active men age 36 ± 14 y were recruited. Subjects performed submaximal treadmill exercise in 3 randomized test conditions: (1) 400 mg ibuprofen and 1000 mg acetaminophen (IBU/APAP), (2) 1000 mg acetaminophen (APAP), and (3) a control condition (CTRL). Acetaminophen and ibuprofen were used to block the effect of IL-6 at a central and peripheral level, respectively. T C , skin temperature, and heart rate were measured continuously during the submaximal exercise tests. Baseline values of T C , skin temperature, and heart rate did not differ across conditions. Serum IL-6 concentrations increased in all 3 conditions. A significantly lower peak T C was observed in IBU/APAP (38.8°C ± 0.4°C) vs CTRL (39.2°C ± 0.5°C, P = .02) but not in APAP (38.9°C ± 0.4°C) vs CTRL. Similarly, a lower ΔT C was observed in IBU/APAP (1.7°C ± 0.3°C) vs CTRL (2.0°C ± 0.5°C, P exercise compared with a CTRL. This observation suggests that a prostaglandin-E2-induced elevated hypothalamic temperature set point may contribute to the exercise-induced rise in T C .
Gender differences in myogenic regulation along the vascular tree of the gerbil cochlea.

Directory of Open Access Journals (Sweden)

Katrin Reimann

Full Text Available Regulation of cochlear blood flow is critical for hearing due to its exquisite sensitivity to ischemia and oxidative stress. Many forms of hearing loss such as sensorineural hearing loss and presbyacusis may involve or be aggravated by blood flow disorders. Animal experiments and clinical outcomes further suggest that there is a gender preference in hearing loss, with males being more susceptible. Autoregulation of cochlear blood flow has been demonstrated in some animal models in vivo, suggesting that similar to the brain, blood vessels supplying the cochlea have the ability to control flow within normal limits, despite variations in systemic blood pressure. Here, we investigated myogenic regulation in the cochlear blood supply of the Mongolian gerbil, a widely used animal model in hearing research. The cochlear blood supply originates at the basilar artery, followed by the anterior inferior cerebellar artery, and inside the inner ear, by the spiral modiolar artery and the radiating arterioles that supply the capillary beds of the spiral ligament and stria vascularis. Arteries from male and female gerbils were isolated and pressurized using a concentric pipette system. Diameter changes in response to increasing luminal pressures were recorded by laser scanning microscopy. Our results show that cochlear vessels from male and female gerbils exhibit myogenic regulation but with important differences. Whereas in male gerbils, both spiral modiolar arteries and radiating arterioles exhibited pressure-dependent tone, in females, only radiating arterioles had this property. Male spiral modiolar arteries responded more to L-NNA than female spiral modiolar arteries, suggesting that NO-dependent mechanisms play a bigger role in the myogenic regulation of male than female gerbil cochlear vessels.
Determinants of exercise-induced pulmonary arterial hypertension in systemic sclerosis.

Science.gov (United States)

Voilliot, Damien; Magne, Julien; Dulgheru, Raluca; Kou, Seisyou; Henri, Christine; Laaraibi, Saloua; Sprynger, Muriel; Andre, Béatrice; Pierard, Luc A; Lancellotti, Patrizio

2014-05-15

Exercise-induced pulmonary arterial hypertension (EIPH) in systemic sclerosis (SSc) has already been observed but its determinants remain unclear. The aim of this study was to determine the incidence and the determinants of EIPH in SSc. We prospectively enrolled 63 patients with SSc (age 54±3years, 76% female) followed in CHU Sart-Tilman in Liège. All patients underwent graded semi-supine exercise echocardiography. Systolic pulmonary arterial pressure (sPAP) was derived from the peak velocity of the tricuspid regurgitation jet and adding the estimation of right atrial pressure, both at rest and during exercise. Resting pulmonary arterial hypertension (PH) was defined as sPAP > 35 mmHg and EIPH as sPAP > 50 mmHg during exercise. The following formulas were used: mean PAP (mPAP) = 0.61 × sPAP + 2, left atrial pressure (LAP)=1.9+1.24 × left ventricular (LV) E/e' and pulmonary vascular resistance (PVR)=(mPAP-LAP)/LV cardiac output (CO) and slope of mPAP-LVCO relationship=changes in mPAP/changes in LVCO. Resting PH was present in 3 patients (7%) and 21 patients developed EIPH (47%). Patients with EIPH had higher resting LAP (10.3 ± 2.2 versus 8.8 ± 2.3 mmHg; p = 0.03), resting PVR (2.6 ± 0.8 vs. 1.4 ± 1.1 Woods units; p=0.004), exercise LAP (13.3 ± 2.3 vs. 9 ± 1.7 mmHg; p exercise PVR (3.6 ± 0.7 vs. 2.1 ± 0.9 Woods units; p = 0.02) and slope of mPAP-LVCO (5.8 ± 2.4 vs. 2.9 ± 2.1 mmHg/L/min; p age and gender, exercise LAP (β=3.1 ± 0.8; p=0.001) and exercise PVR (β=7.9 ± 1.7; p=0.0001) were independent determinants of exercise sPAP. EIPH is frequent in SSc patients and is mainly related to both increased exercise LV filling pressure and exercise PVR. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Myogenin regulates exercise capacity and skeletal muscle metabolism in the adult mouse.

Directory of Open Access Journals (Sweden)

Jesse M Flynn

2010-10-01

Full Text Available Although skeletal muscle metabolism is a well-studied physiological process, little is known about how it is regulated at the transcriptional level. The myogenic transcription factor myogenin is required for skeletal muscle development during embryonic and fetal life, but myogenin's role in adult skeletal muscle is unclear. We sought to determine myogenin's function in adult muscle metabolism. A Myog conditional allele and Cre-ER transgene were used to delete Myog in adult mice. Mice were analyzed for exercise capacity by involuntary treadmill running. To assess oxidative and glycolytic metabolism, we performed indirect calorimetry, monitored blood glucose and lactate levels, and performed histochemical analyses on muscle fibers. Surprisingly, we found that Myog-deleted mice performed significantly better than controls in high- and low-intensity treadmill running. This enhanced exercise capacity was due to more efficient oxidative metabolism during low- and high-intensity exercise and more efficient glycolytic metabolism during high-intensity exercise. Furthermore, Myog-deleted mice had an enhanced response to long-term voluntary exercise training on running wheels. We identified several candidate genes whose expression was altered in exercise-stressed muscle of mice lacking myogenin. The results suggest that myogenin plays a critical role as a high-level transcriptional regulator to control the energy balance between aerobic and anaerobic metabolism in adult skeletal muscle.
Specific Oral Tolerance Induction Using IFN-Gamma in 2 Cases of Food-Dependent Exercise-Induced Anaphylaxis

Directory of Open Access Journals (Sweden)

Geunwoong Noh

2013-01-01

Full Text Available Anaphylaxis induced by exercise after the intake of certain foods is referred to as food-dependent exercise-induced anaphylaxis (FDEIA. Only the preventive medication such as oral sodium cromoglycate and oral combined cetirizine-montelukast was tried in FDEIA. Specific oral tolerance induction (SOTI using IFN-gamma was tried in 2 cases of FDEIA for wheat. Merely, exercise accompanied every treatment just after the intake of allergenic foods during treatment. Patients acquired tolerance for wheat in both cases successfully. After treatment, two patients take wheat in their food living freely. Conclusively, SOTI using IFN-gamma was effective as the causative treatment for allergenic foods in FDEIA.
Single molecular image of cytosolic free Ca2+ of skeletal muscle cells in rats pre- and post-exercise-induced fatigue

Science.gov (United States)

Liu, Yi; Zhang, Heming; Zhao, Yanping; Liu, Zhiming

2009-08-01

A growing body of literature indicated the cytosolic free Ca2+ concentration of skeletal muscle cells changes significantly during exercise-induced fatigue. But it is confusing whether cytosolic free Ca2+ concentration increase or decrease. Furthermore, current researches mainly adopt muscle tissue homogenate as experiment material, but the studies based on cellular and subcellular level is seldom. This study is aimed to establish rat skeletal muscle cell model of exercise-induced fatigue, and confirm the change of cytosolic free Ca2+ concentration of skeletal muscle cells in rats preand post- exercise-induced fatigue. In this research, six male Wistar rats were randomly divided into two groups: control group (n=3) and exercise-induced fatigue group (n=3). The former group were allowed to freely move and the latter were forced to loaded swimming to exhaustive. Three days later, all the rats were sacrificed, the muscle tissue from the same site of skeletal muscle were taken out and digested to cells. After primary culture of the two kinds of skeletal muscle cells from tissue, a fluorescent dye-Fluo-3 AM was used to label the cytosolic free Ca2+. The fluorescent of Ca2+ was recorded by confocal laser scanning microscopy. The results indicated that, the Ca2+ fluorescence intensity of cells from the rat of exercise-induced fatigue group was significantly higher than those in control group. In conclusion, cytosolic free Ca2+ concentration of skeletal muscle cells has a close relation with exercise-induced fatigue, and the increase of cytosolic free Ca2+ concentration may be one of the important factors of exercise-induced fatigue.
Allergies and Exercise-Induced Bronchoconstriction in a Youth Academy and Reserve Professional Soccer Team.

Science.gov (United States)

Bougault, Valérie; Drouard, François; Legall, Franck; Dupont, Grégory; Wallaert, Benoit

2017-09-01

A high prevalence of respiratory allergies and exercise-induced bronchoconstriction (EIB) has been reported among endurance athletes. This study was designed to analyze the frequency of sensitization to respiratory allergens and EIB in young soccer players. Prospective cohort design. Youth academy and reserve professional soccer team during the seasons 2012 to 2013 and 2013 to 2014. Eighty-five soccer players (mean age: 20 ± 4 years) participated. Players underwent skin prick tests (SPTs) during the seasons 2012 to 2013 and 2013 to 2014. Spirometry and a eucapnic voluntary hyperpnea test were performed on soccer players during the first season 2012 to 2013 (n = 51) to detect EIB. Two self-administered questionnaires on respiratory history and allergic symptoms (European Community Respiratory Health Survey and Allergy Questionnaire for Athletes) were also distributed during both seasons (n = 59). The number of positive SPTs, exercise-induced respiratory symptoms, presence of asthma, airway obstruction, and EIB. Forty-nine percent of players were sensitized to at least one respiratory allergen, 33% reported an allergic disease, 1 player presented airway obstruction at rest, and 16% presented EIB. Factors predictive of EIB were self-reported exercise-induced symptoms and sensitization to at least 5 allergens. Questioning players about exercise-induced respiratory symptoms and allergies as well as spirometry at the time of the inclusion medical checkup would improve management of respiratory health of soccer players and would constitute inexpensive preliminary screening to select players requiring indirect bronchial provocation test or SPTs. This study showed that despite low frequencies, EIB and allergies are underdiagnosed and undertreated in young soccer players.
Low-Intensity Repetitive Exercise Induced Rhabdomyolysis

Directory of Open Access Journals (Sweden)

Mina Tran

2015-01-01

Full Text Available Rhabdomyolysis is a rare condition caused by the proteins of damaged muscle cells entering the bloodstream and damaging the kidneys. Common symptoms of rhabdomyolysis are muscle pain and fatigue in conjunction with dark urine; kidney damage is a common symptom among these patients. We present a case of a 23-year-old woman who displayed myalgia in the upper extremities caused by low-intensity and high-repetition exercise. She was successfully diagnosed and treated for exertional rhabdomyolysis. This patient had no significant medical history that would induce this condition. We urge the emergency medical community to observe and monitor patients that complain of myalgia to ensure they are not suffering from rhabdomyolysis even in atypical cases.
Changes in Athlete’s Redox State Induced by Habitual and Unaccustomed Exercise

Directory of Open Access Journals (Sweden)

Dusica Z. Djordjevic

2012-01-01

Full Text Available The purpose of this study was to assess the influence of sport-specific and nonspecific bouts of exercise on athletes’ redox state. Blood samples were collected from 14 handball players immediately before and after graded exercise test on the cycle ergometer and handball training. Levels of superoxide anion radical (O2-, hydrogen peroxide (H2O2, nitrites (NO2- as markers of nitric oxide, index of lipid peroxidation (TBARs, glutathione (GSH, superoxide dismutase (SOD, and catalase (CAT activity were determined. Exercise intensity was assessed by a system for heart rate (HR monitoring. Average athletes’ HR was not significantly different between protocols, but protocols differed in total time and time and percentage of time that athletes spent in every HR zone. The laboratory exercise test induced a significant increase of H2O2 and TBARs as well as the decrease of the SOD and CAT activity, while after specific handball training, levels of NO2- were increased and SOD activity decreased. It seems that unaccustomed short intensive physical activity may induce oxidative stress in trained athletes, while sport-specific activity of longer duration and proper warm-up period may not. Further research should show whether the change of protocol testing and the implementation of various supplementations and manual methods can affect the redox equilibrium.
High-intensity exercise training increases the diversity and metabolic capacity of the mouse distal gut microbiota during diet-induced obesity.

Science.gov (United States)

Denou, Emmanuel; Marcinko, Katarina; Surette, Michael G; Steinberg, Gregory R; Schertzer, Jonathan D

2016-06-01

Diet and exercise underpin the risk of obesity-related metabolic disease. Diet alters the gut microbiota, which contributes to aspects of metabolic disease during obesity. Repeated exercise provides metabolic benefits during obesity. We assessed whether exercise could oppose changes in the taxonomic and predicted metagenomic characteristics of the gut microbiota during diet-induced obesity. We hypothesized that high-intensity interval training (HIIT) would counteract high-fat diet (HFD)-induced changes in the microbiota without altering obesity in mice. Compared with chow-fed mice, an obesity-causing HFD decreased the Bacteroidetes-to-Firmicutes ratio and decreased the genetic capacity in the fecal microbiota for metabolic pathways such as the tricarboxylic acid (TCA) cycle. After HFD-induced obesity was established, a subset of mice were HIIT for 6 wk, which increased host aerobic capacity but did not alter body or adipose tissue mass. The effects of exercise training on the microbiota were gut segment dependent and more extensive in the distal gut. HIIT increased the alpha diversity and Bacteroidetes/Firmicutes ratio of the distal gut and fecal microbiota during diet-induced obesity. Exercise training increased the predicted genetic capacity related to the TCA cycle among other aspects of metabolism. Strikingly, the same microbial metabolism indexes that were increased by exercise were all decreased in HFD-fed vs. chow diet-fed mice. Therefore, exercise training directly opposed some of the obesity-related changes in gut microbiota, including lower metagenomic indexes of metabolism. Some host and microbial pathways appeared similarly affected by exercise. These exercise- and diet-induced microbiota interactions can be captured in feces. Copyright © 2016 the American Physiological Society.
Exercise reduces diet-induced cognitive decline and increases hippocampal brain-derived neurotrophic factor in CA3 neurons.

Science.gov (United States)

Noble, Emily E; Mavanji, Vijayakumar; Little, Morgan R; Billington, Charles J; Kotz, Catherine M; Wang, ChuanFeng

2014-10-01

Previous studies have shown that a western diet impairs, whereas physical exercise enhances hippocampus-dependent learning and memory. Both diet and exercise influence expression of hippocampal brain-derived neurotrophic factor (BDNF), which is associated with improved cognition. We hypothesized that exercise reverses diet-induced cognitive decline while increasing hippocampal BDNF. To test the effects of exercise on hippocampal-dependent memory, we compared cognitive scores of Sprague-Dawley rats exercised by voluntary running wheel (RW) access or forced treadmill (TM) to sedentary (Sed) animals. Memory was tested by two-way active avoidance test (TWAA), in which animals are exposed to a brief shock in a specific chamber area. When an animal avoids, escapes or has reduced latency to do either, this is considered a measure of memory. In a second experiment, rats were fed either a high-fat diet or control diet for 16 weeks, then randomly assigned to running wheel access or sedentary condition, and TWAA memory was tested once a week for 7 weeks of exercise intervention. Both groups of exercised animals had improved memory as indicated by reduced latency to avoid and escape shock, and increased avoid and escape episodes (pdiet resulted in poor performance during both the acquisition and retrieval phases of the memory test as compared to controls. Exercise reversed high-fat diet-induced memory impairment, and increased brain-derived neurotrophic factor (BDNF) in neurons of the hippocampal CA3 region. These data suggest that exercise improves memory retrieval, particularly with respect to avoiding aversive stimuli, and may be beneficial in protecting against diet induced cognitive decline, likely via elevated BDNF in neurons of the CA3 region. Published by Elsevier Inc.
Spontaneous Physical Activity Downregulates Pax7 in Cancer Cachexia

Directory of Open Access Journals (Sweden)

Dario Coletti

2016-01-01

Full Text Available Emerging evidence suggests that the muscle microenvironment plays a prominent role in cancer cachexia. We recently showed that NF-kB-induced Pax7 overexpression impairs the myogenic potential of muscle precursors in cachectic mice, suggesting that lowering Pax7 expression may be beneficial in cancer cachexia. We evaluated the muscle regenerative potential after acute injury in C26 colon carcinoma tumor-bearing mice and healthy controls. Our analyses confirmed that the delayed muscle regeneration observed in muscles form tumor-bearing mice was associated with a persistent local inflammation and Pax7 overexpression. Physical activity is known to exert positive effects on cachectic muscles. However, the mechanism by which a moderate voluntary exercise ameliorates muscle wasting is not fully elucidated. To verify if physical activity affects Pax7 expression, we hosted control and C26-bearing mice in wheel-equipped cages and we found that voluntary wheel running downregulated Pax7 expression in muscles from tumor-bearing mice. As expected, downregulation of Pax7 expression was associated with a rescue of muscle mass and fiber size. Our findings shed light on the molecular basis of the beneficial effect exerted by a moderate physical exercise on muscle stem cells in cancer cachexia. Furthermore, we propose voluntary exercise as a physiological tool to counteract the overexpression of Pax7 observed in cancer cachexia.
Ganoderma tsugae Hepatoprotection against Exhaustive Exercise-Induced Liver Injury in Rats

Directory of Open Access Journals (Sweden)

Wan-Teng Lin

2013-01-01

Full Text Available Several studies have been shown that accelerated apoptosis is involved in post-exercise lymphocytopenia and tissue damage after high-intensity exercise. Ganoderma tsugae (GT is one of the well-known medicinal mushrooms that possess various pharmacological functions. This mushroom has traditionally been used for health promotion purposes. This study investigates the hepatoprotective effects of GT on exhaustive exercise-induced liver damage. Twenty-four male Sprague-Dawley rats were randomly divided into four groups and designated as exhaustive exercise only (E, exhaustive exercise with low dosage (EL, medium dosage (EM and high dosage (EH GT at 0, 0.1875, 0.9375 and 1.875 g/kg/day, respectively. After 30 days all rats were euthanized immediately after an exhaustive running challenge on a motorized treadmill. The rat livers were immediately harvested. Evidence of apoptotic liver cell death was revealed using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL assay and caspases mediated cascade events. DNA fragmentation, an apoptosis process, can be examined using TUNEL assay. A few TUNEL-positive hepatocytes, compared to the exercise only group, were observed in the livers from exhaustive animals supplemented with GT. Immunoblot analysis also showed that caspase-6-mediated specific cleavage of lamin A/C was increased significantly in the livers of group E, but was significantly decreased in the EM and EH groups. Our observations demonstrate that GT possesses anti-apoptotic and hepatoprotective potential after exhaustive exercise.
Ganoderma tsugae hepatoprotection against exhaustive exercise-induced liver injury in rats.

Science.gov (United States)

Huang, Chi-Chang; Huang, Wen-Ching; Yang, Suh-Ching; Chan, Chih-Chi; Lin, Wan-Teng

2013-01-29

Several studies have been shown that accelerated apoptosis is involved in post-exercise lymphocytopenia and tissue damage after high-intensity exercise. Ganoderma tsugae (GT) is one of the well-known medicinal mushrooms that possess various pharmacological functions. This mushroom has traditionally been used for health promotion purposes. This study investigates the hepatoprotective effects of GT on exhaustive exercise-induced liver damage. Twenty-four male Sprague-Dawley rats were randomly divided into four groups and designated as exhaustive exercise only (E), exhaustive exercise with low dosage (EL), medium dosage (EM) and high dosage (EH) GT at 0, 0.1875, 0.9375 and 1.875 g/kg/day, respectively. After 30 days all rats were euthanized immediately after an exhaustive running challenge on a motorized treadmill. The rat livers were immediately harvested. Evidence of apoptotic liver cell death was revealed using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and caspases mediated cascade events. DNA fragmentation, an apoptosis process, can be examined using TUNEL assay. A few TUNEL-positive hepatocytes, compared to the exercise only group, were observed in the livers from exhaustive animals supplemented with GT. Immunoblot analysis also showed that caspase-6-mediated specific cleavage of lamin A/C was increased significantly in the livers of group E, but was significantly decreased in the EM and EH groups. Our observations demonstrate that GT possesses anti-apoptotic and hepatoprotective potential after exhaustive exercise.
Validity and reliability of grade scoring in the diagnosis of exercise-induced laryngeal obstruction

DEFF Research Database (Denmark)

Walsted, Emil Schwarz; Hull, James H; Hvedstrup, Jeppe

2017-01-01

The current gold-standard method for diagnosing exercise-induced laryngeal obstruction (EILO) is continuous laryngoscopy during exercise (CLE), with severity classified by a visual grade scoring system. We evaluated the precision of this approach, by evaluating test-retest reliability of CLE...... grade scoring system does not appear to be a robust means for reliably classifying severity of EILO....
High protein diet maintains glucose production during exercise-induced energy deficit: a controlled trial

Science.gov (United States)

Inadequate energy intake induces changes in endogenous glucose production (GP) to preserve muscle mass. Whether addition provision of dietary protein modulates GP response to energy deficit is unclear. The objective was to determine whether exercise-induced energy deficit effects on glucose metaboli...

Exercise-induced bronchospasm: implications for patients with or without asthma in primary care practice

Directory of Open Access Journals (Sweden)

Hayden ML

2011-11-01

Full Text Available Stuart W Stoloff1, Gene L Colice2, Mary Lou Hayden3, Timothy J Craig4, Nancy K Ostrom5, Nemr S Eid6, Jonathan P Parsons71University of Nevada School of Medicine, Reno, NV, 2Washington Hospital Center, Washington, DC, 3University of Virginia, Charlottesville, VA, 4Pennsylvania State University, Hershey, PA, 5Allergy and Asthma Medical Group and Research Center, San Diego, CA, 6University of Louisville, Louisville, KY, 7Ohio State University Asthma Center, Columbus, OH, USAAbstract: Exercise-induced bronchospasm (EIB can represent a substantial barrier to physical activity. We present the cases of two patients with EIB, one with asthma, and one without asthma, who were evaluated at our primary care practice. The first case was a 44-year-old man with a history of seasonal allergic rhinitis but no asthma, who reported difficulty breathing when playing tennis. The second case was a 45-year-old woman who presented with persistent, generally well-controlled asthma, who was now experiencing bouts of coughing and wheezing during exercise. In both cases, an exercise challenge was used to diagnose EIB, and patients were prescribed a short-acting beta agonist to be used immediately before initiating exercise. EIB is a frequently encountered problem among patients presenting to primary care specialists. Affected patients should be made aware of the importance of proactive treatment with a short-acting beta agonist before initiating any exercise.Keywords: asthma, compliance, exercise-induced bronchospasm
Treadmill exercise ameliorates social isolation-induced depression through neuronal generation in rat pups.

Science.gov (United States)

Cho, Jung-Wan; Jung, Sun-Young; Lee, Sang-Won; Lee, Sam-Jun; Seo, Tae-Beom; Kim, Young-Pyo; Kim, Dae-Young

2017-12-01

Social isolation is known to induce emotional and behavioral changes in animals and humans. The effect of treadmill exercise on depression was investigated using social isolated rat pups. The rat pups in the social isolation groups were housed individually. The rat pups in the exercise groups were forced to run on treadmill for 30 min once a day from postnatal day 21 to postnatal day 34. In order to evaluate depression state of rat pups, forced swimming test was performed. Newly generated cells in the hippocampal dentate gyrus were determined by 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry. We examined the expression of 5-hydroxytryptamine (5-HT) and tryptophan hydroxylase (TPH) in the dorsal raphe using immunofluorescence. The expression of brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) was detected by Western blot analysis. The present results demonstrated that social isolation increased resting time and decreased mobility time. Expression of 5-HT and TPH in the dorsal raphe and expression of BDNF and TrkB in the hippocampus were decreased by social isolation. The number of BrdU-positive cells in the hippocampal dentate gyrus was suppressed by social isolation. Treadmill exercise decreased resting time and increased mobility in the social isolated rat pups. Expression of 5-HT, TPH, BDNF, and TrkB was increased by treadmill exercise. The present results suggested that treadmill exercise may ameliorates social isolation-induced depression through increasing neuronal generation.
Exercise-induced endocrine pathologies.

Science.gov (United States)

Warren, M P; Goodman, L R

2003-09-01

There has been a substantial increase in women practicing sports over the past 30 yr. While exercise provides many health benefits, there appears to be a unique set of risks associated with intense exercise for the female athlete. The female athlete triad encompasses these risks, including amenorrhea, osteoporosis and eating disorders. The incidence of menstrual irregularities including primary and secondary amenorrhea and shortened luteal phases is much higher among women partaking in athletics, specifically in sports requiring low body weight for performance and aesthetics. The hormone pattern seen in these amenorrheic athletes includes a decrease in GnRH pulses from the hypothalamus, which results in decreased pulsatile secretion of LH and FSH and shuts down stimulation of the ovary. The recently discovered hormone leptin may also play a large role as a significant mediator of reproductive function. The prevalence of eating disorders is high among female athletes who practice sports which emphasize leanness. Consequently, the cause of menstrual irregularities is not due to the exercise alone, but to chronic inadequate or restrictive caloric intake that does not compensate for the energy expenditure. The most dangerous risk associated with amenorrhea for the female athlete is the impact on the skeleton. Complications associated with amenorrhea include compromised bone density, failure to attain peak bone mass in adolescence and increased risk of stress fractures. The diagnosis of exercise-associated menstrual dysfunctions is one of exclusion. The most effective treatment is to decrease the intensity of the exercise and increase the nutritional intake. Hormone replacement has also been under investigation as a possible treatment.
Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training.

Science.gov (United States)

West, Daniel W D; Phillips, Stuart M

2012-07-01

The purpose of this study was to investigate associations between acute exercise-induced hormone responses and adaptations to high intensity resistance training in a large cohort (n = 56) of young men. Acute post-exercise serum growth hormone (GH), free testosterone (fT), insulin-like growth factor (IGF-1) and cortisol responses were determined following an acute intense leg resistance exercise routine at the midpoint of a 12-week resistance exercise training study. Acute hormonal responses were correlated with gains in lean body mass (LBM), muscle fibre cross-sectional area (CSA) and leg press strength. There were no significant correlations between the exercise-induced elevations (area under the curve-AUC) of GH, fT and IGF-1 and gains in LBM or leg press strength. Significant correlations were found for cortisol, usually assumed to be a hormone indicative of catabolic drive, AUC with change in LBM (r = 0.29, P training-induced changes in fibre CSA and LBM (cortisol only), but not with changes in strength.
Cyclin D2 is a critical mediator of exercise-induced cardiac hypertrophy.

Science.gov (United States)

Luckey, Stephen W; Haines, Chris D; Konhilas, John P; Luczak, Elizabeth D; Messmer-Kratzsch, Antke; Leinwand, Leslie A

2017-12-01

A number of signaling pathways underlying pathological cardiac hypertrophy have been identified. However, few studies have probed the functional significance of these signaling pathways in the context of exercise or physiological pathways. Exercise studies were performed on females from six different genetic mouse models that have been shown to exhibit alterations in pathological cardiac adaptation and hypertrophy. These include mice expressing constitutively active glycogen synthase kinase-3β (GSK-3βS9A), an inhibitor of CaMK II (AC3-I), both GSK-3βS9A and AC3-I (GSK-3βS9A/AC3-I), constitutively active Akt (myrAkt), mice deficient in MAPK/ERK kinase kinase-1 (MEKK1 -/- ), and mice deficient in cyclin D2 (cyclin D2 -/- ). Voluntary wheel running performance was similar to NTG littermates for five of the mouse lines. Exercise induced significant cardiac growth in all mouse models except the cyclin D2 -/- mice. Cardiac function was not impacted in the cyclin D2 -/- mice and studies using a phospho-antibody array identified six proteins with increased phosphorylation (greater than 150%) and nine proteins with decreased phosphorylation (greater than 33% decrease) in the hearts of exercised cyclin D2 -/- mice compared to exercised NTG littermate controls. Our results demonstrate that unlike the other hypertrophic signaling molecules tested here, cyclin D2 is an important regulator of both pathologic and physiological hypertrophy. Impact statement This research is relevant as the hypertrophic signaling pathways tested here have only been characterized for their role in pathological hypertrophy, and not in the context of exercise or physiological hypertrophy. By using the same transgenic mouse lines utilized in previous studies, our findings provide a novel and important understanding for the role of these signaling pathways in physiological hypertrophy. We found that alterations in the signaling pathways tested here had no impact on exercise performance. Exercise
Creatine supplementation prevents acute strength loss induced by concurrent exercise.

Science.gov (United States)

de Salles Painelli, Vítor; Alves, Victor Tavares; Ugrinowitsch, Carlos; Benatti, Fabiana Braga; Artioli, Guilherme Giannini; Lancha, Antonio Herbert; Gualano, Bruno; Roschel, Hamilton

2014-08-01

To investigate the effect of creatine (CR) supplementation on the acute interference induced by aerobic exercise on subsequent maximum dynamic strength (1RM) and strength endurance (SE, total number of repetitions) performance. Thirty-two recreationally strength-trained men were submitted to a graded exercise test to determine maximal oxygen consumption (VO2max: 41.56 ± 5.24 ml kg(-1) min(-1)), anaerobic threshold velocity (ATv: 8.3 ± 1.18 km h(-1)), and baseline performance (control) on the 1RM and SE (4 × 80 % 1RM to failure) tests. After the control tests, participants were randomly assigned to either a CR (20 g day(-1) for 7 days followed by 5 g day(-1) throughout the study) or a placebo (PL-dextrose) group, and then completed 4 experimental sessions, consisting of a 5-km run on a treadmill either continuously (90 % ATv) or intermittently (1:1 min at vVO2max) followed by either a leg- or bench-press SE/1RM test. CR was able to maintain the leg-press SE performance after the intermittent aerobic exercise when compared with C (p > 0.05). On the other hand, the PL group showed a significant decrease in leg-press SE (p ≤ 0.05). CR supplementation significantly increased bench-press SE after both aerobic exercise modes, while the bench-press SE was not affected by either mode of aerobic exercise in the PL group. Although small increases in 1RM were observed after either continuous (bench press and leg press) or intermittent (bench press) aerobic exercise in the CR group, they were within the range of variability of the measurement. The PL group only maintained their 1RM. In conclusion, the acute interference effect on strength performance observed in concurrent exercise may be counteracted by CR supplementation.
Nanolipodendrosome-loaded glatiramer acetate and myogenic differentiation 1 as augmentation therapeutic strategy approaches in muscular dystrophy.

Science.gov (United States)

Afzal, Ehsan; Zakeri, Saba; Keyhanvar, Peyman; Bagheri, Meisam; Mahjoubi, Parvin; Asadian, Mahtab; Omoomi, Nogol; Dehqanian, Mohammad; Ghalandarlaki, Negar; Darvishmohammadi, Tahmineh; Farjadian, Fatemeh; Golvajoee, Mohammad Sadegh; Afzal, Shadi; Ghaffari, Maryam; Cohan, Reza Ahangari; Gravand, Amin; Ardestani, Mehdi Shafiee

2013-01-01

[Corrected] Muscular dystrophies consist of a number of juvenile and adult forms of complex disorders which generally cause weakness or efficiency defects affecting skeletal muscles or, in some kinds, other types of tissues in all parts of the body are vastly affected. In previous studies, it was observed that along with muscular dystrophy, immune inflammation was caused by inflammatory cells invasion - like T lymphocyte markers (CD8+/CD4+). Inflammatory processes play a major part in muscular fibrosis in muscular dystrophy patients. Additionally, a significant decrease in amounts of two myogenic recovery factors (myogenic differentation 1 [MyoD] and myogenin) in animal models was observed. The drug glatiramer acetate causes anti-inflammatory cytokines to increase and T helper (Th) cells to induce, in an as yet unknown mechanism. MyoD recovery activity in muscular cells justifies using it alongside this drug. In this study, a nanolipodendrosome carrier as a drug delivery system was designed. The purpose of the system was to maximize the delivery and efficiency of the two drug factors, MyoD and myogenin, and introduce them as novel therapeutic agents in muscular dystrophy phenotypic mice. The generation of new muscular cells was analyzed in SW1 mice. Then, immune system changes and probable side effects after injecting the nanodrug formulations were investigated. The loaded lipodendrimer nanocarrier with the candidate drug, in comparison with the nandrolone control drug, caused a significant increase in muscular mass, a reduction in CD4+/CD8+ inflammation markers, and no significant toxicity was observed. The results support the hypothesis that the nanolipodendrimer containing the two candidate drugs will probably be an efficient means to ameliorate muscular degeneration, and warrants further investigation.
The stream of precursors that colonizes the thymus proceeds selectively through the early T lineage precursor stage of T cell development

Science.gov (United States)

Benz, Claudia; Martins, Vera C.; Radtke, Freddy; Bleul, Conrad C.

2008-01-01

T cell development in the thymus depends on continuous colonization by hematopoietic precursors. Several distinct T cell precursors have been identified, but whether one or several independent precursor cell types maintain thymopoiesis is unclear. We have used thymus transplantation and an inducible lineage-tracing system to identify the intrathymic precursor cells among previously described thymus-homing progenitors that give rise to the T cell lineage in the thymus. Extrathymic precursors were not investigated in these studies. Both approaches show that the stream of T cell lineage precursor cells, when entering the thymus, selectively passes through the early T lineage precursor (ETP) stage. Immigrating precursor cells do not exhibit characteristics of double-negative (DN) 1c, DN1d, or DN1e stages, or of populations containing the common lymphoid precursor 2 (CLP-2) or the thymic equivalent of circulating T cell progenitors (CTPs). It remains possible that an unknown hematopoietic precursor cell or previously described extrathymic precursors with a CLP, CLP-2, or CTP phenotype feed into T cell development by circumventing known intrathymic T cell lineage progenitor cells. However, it is clear that of the known intrathymic precursors, only the ETP population contributes significant numbers of T lineage precursors to T cell development. PMID:18458114
Stress-Induced Depression Is Alleviated by Aerobic Exercise Through Up-Regulation of 5-Hydroxytryptamine 1A Receptors in Rats

Directory of Open Access Journals (Sweden)

Tae Woon Kim

2015-03-01

Full Text Available Purpose: Stress is associated with depression, which induces many psychiatric disorders. Serotonin, also known as 5-hydroxy-tryptamine (5-HT, acts as a biochemical messenger and regulator in the brain. It also mediates several important physiological functions. Depression is closely associated with an overactive bladder. In the present study, we investigated the effect of treadmill exercise on stress-induced depression while focusing on the expression of 5-HT 1A (5-H1A receptors in the dorsal raphe. Methods: Stress was induced by applying a 0.2-mA electric foot shock to rats. Each set of electric foot shocks comprised a 6-second shock duration that was repeated 10 times with a 30-second interval. Three sets of electric foot shocks were applied each day for 7 days. For the confirmation of depressive state, a forced swimming test was performed. To visualize the expression of 5-HT and tryptophan hydroxylase (TPH, immunohistochemistry for 5-HT and TPH in the dorsal raphe was performed. Expression of 5-H1A receptors was determined by western blot analysis. Results: A depressive state was induced by stress, and treadmill exercise alleviated the depression symptoms in the stress-induced rats. Expressions of 5-HT, TPH, and HT 1A in the dorsal raphe were reduced by the induction of stress. Treadmill exercise increased 5-HT, TPH, and HT 1A expressions in the stress-induced rats. Conclusions: Treadmill exercise enhanced 5-HT synthesis through the up-regulation of 5-HT1A receptors, and improved the stress-induced depression. In the present study, treadmill exercise improved depression symptoms by enhancing 5-HT1A receptor expression. The present results suggest that treadmill exercise might be helpful for the alleviation of overactive bladder and improve sexual function.
Stress-Induced Depression Is Alleviated by Aerobic Exercise Through Up-Regulation of 5-Hydroxytryptamine 1A Receptors in Rats.

Science.gov (United States)

Kim, Tae Woon; Lim, Baek Vin; Baek, Dongjin; Ryu, Dong-Soo; Seo, Jin Hee

2015-03-01

Stress is associated with depression, which induces many psychiatric disorders. Serotonin, also known as 5-hydroxy-tryptamine (5-HT), acts as a biochemical messenger and regulator in the brain. It also mediates several important physiological functions. Depression is closely associated with an overactive bladder. In the present study, we investigated the effect of treadmill exercise on stress-induced depression while focusing on the expression of 5-HT 1A (5-H1A) receptors in the dorsal raphe. Stress was induced by applying a 0.2-mA electric foot shock to rats. Each set of electric foot shocks comprised a 6-second shock duration that was repeated 10 times with a 30-second interval. Three sets of electric foot shocks were applied each day for 7 days. For the confirmation of depressive state, a forced swimming test was performed. To visualize the expression of 5-HT and tryptophan hydroxylase (TPH), immunohistochemistry for 5-HT and TPH in the dorsal raphe was performed. Expression of 5-H1A receptors was determined by western blot analysis. A depressive state was induced by stress, and treadmill exercise alleviated the depression symptoms in the stress-induced rats. Expressions of 5-HT, TPH, and HT 1A in the dorsal raphe were reduced by the induction of stress. Treadmill exercise increased 5-HT, TPH, and HT 1A expressions in the stress-induced rats. Treadmill exercise enhanced 5-HT synthesis through the up-regulation of 5-HT1A receptors, and improved the stress-induced depression. In the present study, treadmill exercise improved depression symptoms by enhancing 5-HT1A receptor expression. The present results suggest that treadmill exercise might be helpful for the alleviation of overactive bladder and improve sexual function.
The cost-effectiveness of TheraBite® as treatment for acute myogenic temporomandibular disorder

NARCIS (Netherlands)

Heres Diddens, A.; Kraaijenga, S.; Coupe, V.; Hilgers, F.; van der Molen, L.; Smeele, L.; Retèl, V.P.

2017-01-01

Objective: Temporomandibular disorder (TMD) is a very common and costly pain problem concerning the temporomandibular joint. A previous study has shown that for the treatment of acute myogenic TMD, TheraBite® (TB) offers a faster and greater effect than usual care consisting of physical therapy
The Impaired Function of Macrophages Induced by Strenuous Exercise Could Not Be Ameliorated by BCAA Supplementation.

Science.gov (United States)

Xiao, Weihua; Chen, Peijie; Liu, Xiaoguang; Zhao, Linlin

2015-10-21

The aim of this study was to evaluate the effect of strenuous exercise on the functions of peritoneal macrophages in rats and to test the hypothesis that branched-chain amino acid (BCAA) supplementation will be beneficial to the macrophages of rats from strenuous exercise. Forty male Wistar rats were randomly divided into five groups: (C) Control, E) Exercise, (E1) Exercise with one week to recover, (ES) Exercise + Supplementation and (ES1) Exercise + Supplementation with 1 week to recover. All rats except those of the sedentary control were subjected to four weeks of strenuous exercise. Blood hemoglobin, serum testosterone and BCAA levels were tested. Peritoneal macrophages functions were also determined at the same time. The data showed that hemoglobin, testosterone, BCAA levels, and body weight in group E decreased significantly as compared with that of group C. Meanwhile, phagocytosis capacity (decreased by 17.07%, p = 0.031), reactive oxygen species (ROS) production (decreased by 26%, p = 0.003) and MHC II mRNA (decreased by 22%, p = 0.041) of macrophages decreased in the strenuous exercise group as compared with group C. However, the chemotaxis of macrophages did not change significantly. In addition, BCAA supplementation could slightly increase the serum BCAA levels of rats from strenuous exercise (increased by 6.70%, p > 0.05). Moreover, the body weight, the blood hemoglobin, the serum testosterone and the function of peritoneal macrophages in group ES did not change significantly as compared with group E. These results suggest that long-term intensive exercise impairs the function of macrophages, which is essential for microbicidal capability. This may represent a novel mechanism of immunosuppression induced by strenuous exercise. Moreover, the impaired function of macrophage induced by strenuous exercise could not be ameliorated by BCAA supplementation in the dosing and timing used for this study.
The Impaired Function of Macrophages Induced by Strenuous Exercise Could Not Be Ameliorated by BCAA Supplementation

Directory of Open Access Journals (Sweden)

Weihua Xiao

2015-10-01

Full Text Available The aim of this study was to evaluate the effect of strenuous exercise on the functions of peritoneal macrophages in rats and to test the hypothesis that branched-chain amino acid (BCAA supplementation will be beneficial to the macrophages of rats from strenuous exercise. Forty male Wistar rats were randomly divided into five groups: (C Control, E Exercise, (E1 Exercise with one week to recover, (ES Exercise + Supplementation and (ES1 Exercise + Supplementation with 1 week to recover. All rats except those of the sedentary control were subjected to four weeks of strenuous exercise. Blood hemoglobin, serum testosterone and BCAA levels were tested. Peritoneal macrophages functions were also determined at the same time. The data showed that hemoglobin, testosterone, BCAA levels, and body weight in group E decreased significantly as compared with that of group C. Meanwhile, phagocytosis capacity (decreased by 17.07%, p = 0.031, reactive oxygen species (ROS production (decreased by 26%, p = 0.003 and MHC II mRNA (decreased by 22%, p = 0.041 of macrophages decreased in the strenuous exercise group as compared with group C. However, the chemotaxis of macrophages did not change significantly. In addition, BCAA supplementation could slightly increase the serum BCAA levels of rats from strenuous exercise (increased by 6.70%, p > 0.05. Moreover, the body weight, the blood hemoglobin, the serum testosterone and the function of peritoneal macrophages in group ES did not change significantly as compared with group E. These results suggest that long-term intensive exercise impairs the function of macrophages, which is essential for microbicidal capability. This may represent a novel mechanism of immunosuppression induced by strenuous exercise. Moreover, the impaired function of macrophage induced by strenuous exercise could not be ameliorated by BCAA supplementation in the dosing and timing used for this study.
Exercise-induced hypertension, cardiovascular events, and mortality in patients undergoing exercise stress testing: a systematic review and meta-analysis.

Science.gov (United States)

Schultz, Martin G; Otahal, Petr; Cleland, Verity J; Blizzard, Leigh; Marwick, Thomas H; Sharman, James E

2013-03-01

The prognostic relevance of a hypertensive response to exercise (HRE) is ill-defined in individuals undergoing exercise stress testing. The study described here was intended to provide a systematic review and meta-analysis of published literature to determine the value of exercise-related blood pressure (BP) (independent of office BP) for predicting cardiovascular (CV) events and mortality. Online databases were searched for published longitudinal studies reporting exercise-related BP and CV events and mortality rates. We identified for review 12 longitudinal studies with a total of 46,314 individuals without significant coronary artery disease, with total CV event and mortality rates recorded over a mean follow-up of 15.2±4.0 years. After adjustment for age, office BP, and CV risk factors, an HRE at moderate exercise intensity carried a 36% greater rate of CV events and mortality (95% CI, 1.02-1.83, P = 0.039) than that of subjects without an HRE. Additionally, each 10mm Hg increase in systolic BP during exercise at moderate intensity was accompanied by a 4% increase in CV events and mortality, independent of office BP, age, or CV risk factors (95% CI, 1.01-1.07, P = 0.02). Systolic BP at maximal workload was not significantly associated with the outcome of an increased rate of CV, whether analyzed as a categorical (HR=1.49, 95% CI, 0.90-2.46, P = 0.12) or a continuous (HR=1.01, 95% CI, 0.98-1.04, P = 0.53) variable. An HRE at moderate exercise intensity during exercise stress testing is an independent risk factor for CV events and mortality. This highlights the need to determine underlying pathophysiological mechanisms of exercise-induced hypertension.
[Electromyographic differential diagnosis in cases of abducens nerve paresis with nuclear or distal neurogenic sive myogenic origine (author's transl)].

Science.gov (United States)

Heuser, M

1979-09-01

Abducens nerve paresis may be of nuclear, of peripheral distal neurogenic origine, or is simulated by a myogenic weakness of abduction. Polygraphic emg analysis of the oculoauricularphenomenon (oap) permits a differentiation. In the emg, the oap proved to be a physiologic and constant automatic and always bilateral interaction between the hemolateral abducens nerve and both Nn. faciales with corresponding and obligatory coinnervation of the Mm. retroauricularis of the external ear. In case of medullary, nuclear or internuclear lesions, the oap is disturbed, instable, diminished or abolished, whereas in distal neurogenic or myogenic paresis, even in complete paralysis the oap is bilaterally well preserved.
Autophagy activation, not peroxisome proliferator-activated receptor γ coactivator 1α, may mediate exercise-induced improvements in glucose handling during diet-induced obesity.

Science.gov (United States)

Rosa-Caldwell, Megan E; Brown, Jacob L; Lee, David E; Blackwell, Thomas A; Turner, Kyle W; Brown, Lemuel A; Perry, Richard A; Haynie, Wesley S; Washington, Tyrone A; Greene, Nicholas P

2017-09-01

What is the central question of this study? What are the individual and combined effects of muscle-specific peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) overexpression and physical activity during high-fat feeding on glucose and exercise tolerance? What is the main finding and its importance? Our main finding is that muscle-specific PGC-1α overexpression provides no protection against lipid-overload pathologies nor does it enhance exercise adaptations. Instead, physical activity, regardless of PGC-1α content, protects against high-fat diet-induced detriments. Activation of muscle autophagy was correlated with exercise protection, suggesting that autophagy might be a mediating factor for exercise-induced protection from lipid overload. The prevalence of glucose intolerance is alarmingly high. Efforts to promote mitochondrial biogenesis through peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) to mitigate glucose intolerance have been controversial. However, physical activity remains a primary means to alleviate the condition. The aim of this study was to determine the combined effects of muscle-specific overexpression of PGC-1α and physical activity on glucose handling during diet-induced obesity. Wild-type (WT, ∼20) and PGC-1α muscle transgenic (MCK-PGC-1α, ∼20) mice were given a Western diet (WD) at 8 weeks age and allowed to consume food ab libitum throughout the study. At 12 weeks of age, all animals were divided into sedentary (SED) or voluntary wheel running (VWR) interventions. At 7, 11 and 15 weeks of age, animals underwent glucose tolerance tests (GTT) and graded exercise tests (GXT). At 16 weeks of age, tissues were collected. At 11 weeks, the MCK-PGC-1α animals had 50% greater glucose tolerance integrated area under the curve compared with WT. However, at 15 weeks, SED animals also had greater GTT integrated area under the curve compared with VWR, regardless of genotype; furthermore, SED
Role of Exercise-Induced Cardiac Remodeling in Ovariectomized Female Rats

Directory of Open Access Journals (Sweden)

Renáta Szabó

2018-01-01

Full Text Available Myocardial extracellular matrix (ECM is essential for proper cardiac function and structural integrity; thus, the disruption of ECM homeostasis is associated with several pathological processes. Female Wistar rats underwent surgical ovariectomy (OVX or sham operation (SO and were then divided into eight subgroups based on the type of diet (standard chow or high-triglyceride diet/HT and exercise (with or without running. After 12 weeks, cardiac MMP-2 activity, tissue inhibitor of metalloproteinase-2, content of collagen type I, the level of nitrotyrosine (3-NT and glutathione (GSH, and the ratio of infarct size were determined. Our results show that OVX and HT diet caused an excessive accumulation of collagen; however, this increase was not observed in the trained animals. Twelve weeks of exercise promoted elevation in the levels of 3-NT and GSH and similarly an increase in MMP-2 activity of both SO and OVX animals. The high infarct-size ratio caused by OVX and HT diet was mitigated by physical exercise. Our findings demonstrate that ovarian estrogen loss and HT diet caused collagen accumulation and increased ratio of the infarct size. However, exercise-induced cardiac remodeling serves as a compensatory mechanism by enhancing MMP-2 activity and reducing fibrosis, thus minimizing the ischemia/reperfusion injury.
Aerobic training suppresses exercise-induced lipid peroxidation and inflammation in overweight/obese adolescent girls.

Science.gov (United States)

Youssef, Hala; Groussard, Carole; Lemoine-Morel, Sophie; Pincemail, Joel; Jacob, Christophe; Moussa, Elie; Fazah, Abdallah; Cillard, Josiane; Pineau, Jean-Claude; Delamarche, Arlette

2015-02-01

This study aimed to determine whether aerobic training could reduce lipid peroxidation and inflammation at rest and after maximal exhaustive exercise in overweight/obese adolescent girls. Thirty-nine adolescent girls (14-19 years old) were classified as nonobese or overweight/obese and then randomly assigned to either the nontrained or trained group (12-week multivariate aerobic training program). Measurements at the beginning of the experiment and at 3 months consisted of body composition, aerobic fitness (VO2peak) and the following blood assays: pre- and postexercise lipid peroxidation (15F2a-isoprostanes [F2-Isop], lipid hydroperoxide [ROOH], oxidized LDL [ox-LDL]) and inflammation (myeloperoxidase [MPO]) markers. In the overweight/ obese group, the training program significantly increased their fat-free mass (FFM) and decreased their percentage of fat mass (%FM) and hip circumference but did not modify their VO2peak. Conversely, in the nontrained overweight/obese group, weight and %FM increased, and VO2peak decreased, during the same period. Training also prevented exercise-induced lipid peroxidation and/or inflammation in overweight/obese girls (F2-Isop, ROOH, ox-LDL, MPO). In addition, in the trained overweight/obese group, exercise-induced changes in ROOH, ox-LDL and F2-Isop were correlated with improvements in anthropometric parameters (waist-to-hip ratio, %FM and FFM). In conclusion aerobic training increased tolerance to exercise-induced oxidative stress in overweight/obese adolescent girls partly as a result of improved body composition.
Wheat-Dependent Exercise-Induced Anaphylaxis Sensitized with Hydrolyzed Wheat Protein in Soap

Directory of Open Access Journals (Sweden)

Yuko Chinuki

2012-01-01

Full Text Available Wheat-dependent exercise-induced anaphylaxis (WDEIA is a specific form of wheat allergy typically induced by exercise after ingestion of wheat products. Wheat ω-5 gliadin is a major allergen associated with conventional WDEIA, and detection of serum immunoglobulin E (IgE specific to recombinant ω-5 gliadin is a reliable method for its diagnosis. Recently, an increased incidence of a new subtype of WDEIA, which is likely to be sensitized via a percutaneous and/or rhinoconjunctival route to hydrolyzed wheat protein (HWP, has been observed. All of the patients with this new subtype had used the same brand of soap, which contained HWP. Approximately half of these patients developed contact allergy several months later and subsequently developed WDEIA. In each of these patients, contact allergy with soap exposure preceded food ingestion-induced reactions. Other patients directly developed generalized symptoms upon ingestion of wheat products. The predominant observed symptom of the new WDEIA subtype was angioedema of the eyelids; a number of patients developed anaphylaxis. This new subtype of WDEIA has little serum ω-5 gliadin-specific serum IgE.
Nuclear receptors and myokines : mediators of exercise-induced skeletal muscle metabolism

NARCIS (Netherlands)

van Gogh, IJA

2016-01-01

Skeletal muscle is a crucial organ in mediating (exercise-induced) beneficial health effects. In this thesis we gained important knowledge on the molecular biology of the muscle. With our focus on the muscle, we investigated the crosstalk with other organs, the regulation of myokines and the role of

Voluntary exercise prevents colonic inflammation in high-fat diet-induced obese mice by up-regulating PPAR-γ activity

International Nuclear Information System (INIS)

Liu, Wei-Xin; Wang, Ting; Zhou, Feng; Wang, Ying; Xing, Jun-Wei; Zhang, Shen; Gu, Shou-Zhi; Sang, Li-Xuan; Dai, Cong; Wang, Hai-Lan

2015-01-01

Obesity is associated with increased colonic inflammation, which elevates the risk of colon cancer. Although exercise exerts anti-inflammatory actions in multiple chronic diseases associated with inflammation, it is unknown whether this strategy prevents colonic inflammation in obesity. We hypothesized that voluntary exercise would suppress colonic inflammation in high-fat diet (HFD)-induced obesity by modulation of peroxisome proliferator-activated receptor (PPAR)-γ. Male C57Bl/6J mice fed either a control diet (6.5% fat, CON) or a high-fat diet (24% fat, HFD) were divided into sedentary, voluntary exercise or voluntary exercise with PPAR-γ antagonist GW9662 (10 mg/kg/day). All interventions took place for 12 weeks. Compared with CON-sedentary group, HFD-sedentary mice gained significantly more body weight and exhibited metabolic disorders. Molecular studies revealed that HFD-sedentary mice had increased expression of inflammatory mediators and activation of nuclear factor (NF)-κB in the colons, which were associated with decreased expression and activity of PPAR-γ. Voluntary exercise markedly attenuated body weight gain, improved metabolic disorders, and normalized the expression of inflammatory mediators and activation of NF-κB in the colons in HFD-mice while having no effects in CON-animals. Moreover, voluntary exercise significantly increased expression and activity of PPAR-γ in the colons in both HFD- and CON-animals. However, all of these beneficial effects induced by voluntary exercise were abolished by GW9662, which inhibited expression and activity of PPAR-γ. The results suggest that decreased PPAR-γ activity in the colon of HFD-induced obesity may facilitate the inflammatory response and colon carcinogenesis. Voluntary exercise prevents colonic inflammation in HFD-induced obesity by up-regulating PPAR-γ activity. - Highlights: • Obesity down-regulates PPAR-γ in the colon. • Down-regulated colonic PPAR-γ may facilitate inflammatory
Voluntary exercise prevents colonic inflammation in high-fat diet-induced obese mice by up-regulating PPAR-γ activity

Energy Technology Data Exchange (ETDEWEB)

Liu, Wei-Xin, E-mail: weixinliu@yahoo.com [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Wang, Ting; Zhou, Feng; Wang, Ying; Xing, Jun-Wei; Zhang, Shen [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Gu, Shou-Zhi [Department of Anatomy, Seirei Christopher College, Hamamatsu 433-8558 (Japan); Sang, Li-Xuan [Department of Cadre Ward II, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Dai, Cong [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Wang, Hai-Lan [Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou 510300, Guangdong (China)

2015-04-10

Obesity is associated with increased colonic inflammation, which elevates the risk of colon cancer. Although exercise exerts anti-inflammatory actions in multiple chronic diseases associated with inflammation, it is unknown whether this strategy prevents colonic inflammation in obesity. We hypothesized that voluntary exercise would suppress colonic inflammation in high-fat diet (HFD)-induced obesity by modulation of peroxisome proliferator-activated receptor (PPAR)-γ. Male C57Bl/6J mice fed either a control diet (6.5% fat, CON) or a high-fat diet (24% fat, HFD) were divided into sedentary, voluntary exercise or voluntary exercise with PPAR-γ antagonist GW9662 (10 mg/kg/day). All interventions took place for 12 weeks. Compared with CON-sedentary group, HFD-sedentary mice gained significantly more body weight and exhibited metabolic disorders. Molecular studies revealed that HFD-sedentary mice had increased expression of inflammatory mediators and activation of nuclear factor (NF)-κB in the colons, which were associated with decreased expression and activity of PPAR-γ. Voluntary exercise markedly attenuated body weight gain, improved metabolic disorders, and normalized the expression of inflammatory mediators and activation of NF-κB in the colons in HFD-mice while having no effects in CON-animals. Moreover, voluntary exercise significantly increased expression and activity of PPAR-γ in the colons in both HFD- and CON-animals. However, all of these beneficial effects induced by voluntary exercise were abolished by GW9662, which inhibited expression and activity of PPAR-γ. The results suggest that decreased PPAR-γ activity in the colon of HFD-induced obesity may facilitate the inflammatory response and colon carcinogenesis. Voluntary exercise prevents colonic inflammation in HFD-induced obesity by up-regulating PPAR-γ activity. - Highlights: • Obesity down-regulates PPAR-γ in the colon. • Down-regulated colonic PPAR-γ may facilitate inflammatory
Islet transplantation in diabetic rats normalizes basal and exercise-induced energy metabolism

NARCIS (Netherlands)

Houwing, Harmina; Benthem, L.; Suylichem, P.T.R. van; Leest, J. van der; Strubbe, J.H.; Steffens, A.B.

Transplantation of islets of Langerhans in diabetic rats normalizes resting glucose and insulin levels, but it remains unclear whether islet transplantation restores resting and exercise-induced energy metabolism. Therefore, we compared energy metabolism in islet transplanted rats with energy
Myocardial fatty acid utilisation during exercise induced ischemia in patients with coronary artery disease

International Nuclear Information System (INIS)

Virtanen, K.S.; Nikkinen, P.; Lindroth, L.; Kuikka, J.T.

2002-01-01

Aim: Reversible or irreversible myocardial damage due to ischemia correlates with altered membrane functions of the cells. To compare myocardial free fatty acid (FFA) metabolism and flow during exercise induced ischemia we studied ten patients with coronary artery disease but without previous myocardial infarction. Methods: A series of post-exercise single-photon emission computed tomography (SPECT) measurements was performed after injection of 123 I labelled heptadecanoic acid (HDA). Myocardial perfusion was estimated from the separately performed exercise-redistribution thallium study. Fatty acid metabolic rate, thallium uptake and washout were calculated for anterior, lateral, posterior and septal segments. Results: The more reduced post-exercise FFA metabolic rate (-63±18%, mean ±1 SD) compared to flow (-36±16%) was related to the severity of myocardial ischemia and wall motion abnormalities. Conclusion: In this small group of patients, the reduced post-exercise FFA metabolic rate tentatively suggests a parsimonious workload of the exercising myocardium by reducing oxygen consumption in patients with coronary artery disease. (orig.) [de
Vascular Ageing and Exercise: Focus on Cellular Reparative Processes.

Science.gov (United States)

Ross, Mark D; Malone, Eva; Florida-James, Geraint

2016-01-01

Ageing is associated with an increased risk of developing noncommunicable diseases (NCDs), such as diabetes and cardiovascular disease (CVD). The increased risk can be attributable to increased prolonged exposure to oxidative stress. Often, CVD is preceded by endothelial dysfunction, which carries with it a proatherothrombotic phenotype. Endothelial senescence and reduced production and release of nitric oxide (NO) are associated with "vascular ageing" and are often accompanied by a reduced ability for the body to repair vascular damage, termed "reendothelialization." Exercise has been repeatedly shown to confer protection against CVD and diabetes risk and incidence. Regular exercise promotes endothelial function and can prevent endothelial senescence, often through a reduction in oxidative stress. Recently, endothelial precursors, endothelial progenitor cells (EPC), have been shown to repair damaged endothelium, and reduced circulating number and/or function of these cells is associated with ageing. Exercise can modulate both number and function of these cells to promote endothelial homeostasis. In this review we look at the effects of advancing age on the endothelium and these endothelial precursors and how exercise appears to offset this "vascular ageing" process.
Exercise-induced quadriceps muscle fatigue in men and women: effects of arterial oxygen content and respiratory muscle work.

Science.gov (United States)

Dominelli, Paolo B; Molgat-Seon, Yannick; Griesdale, Donald E G; Peters, Carli M; Blouin, Jean-Sébastien; Sekhon, Mypinder; Dominelli, Giulio S; Henderson, William R; Foster, Glen E; Romer, Lee M; Koehle, Michael S; Sheel, A William

2017-08-01

High work of breathing and exercise-induced arterial hypoxaemia (EIAH) can decrease O 2 delivery and exacerbate exercise-induced quadriceps fatigue in healthy men. Women have a higher work of breathing during exercise, dedicate a greater fraction of whole-body V̇O2 towards their respiratory muscles and develop EIAH. Despite a greater reduction in men's work of breathing, the attenuation of quadriceps fatigue was similar between the sexes. The degree of EIAH was similar between sexes, and regardless of sex, those who developed the greatest hypoxaemia during exercise demonstrated the most attenuation of quadriceps fatigue. Based on our previous finding that women have a greater relative oxygen cost of breathing, women appear to be especially susceptible to work of breathing-related changes in quadriceps muscle fatigue. Reducing the work of breathing or eliminating exercise-induced arterial hypoxaemia (EIAH) during exercise decreases the severity of quadriceps fatigue in men. Women have a greater work of breathing during exercise, dedicate a greater fraction of whole-body V̇O2 towards their respiratory muscles, and demonstrate EIAH, suggesting women may be especially susceptible to quadriceps fatigue. Healthy subjects (8 male, 8 female) completed three constant load exercise tests over 4 days. During the first (control) test, subjects exercised at ∼85% of maximum while arterial blood gases and work of breathing were assessed. Subsequent constant load exercise tests were iso-time and iso-work rate, but with EIAH prevented by inspiring hyperoxic gas or work of breathing reduced via a proportional assist ventilator (PAV). Quadriceps fatigue was assessed by measuring force in response to femoral nerve stimulation. For both sexes, quadriceps force was equally reduced after the control trial (-27 ± 2% baseline) and was attenuated with hyperoxia and PAV (-18 ± 1 and -17 ± 2% baseline, P Physiology © 2017 The Physiological Society.
Endurance exercise after orange ingestion anaphylaxis

Directory of Open Access Journals (Sweden)

Manu Gupta

2016-01-01

Full Text Available Endurance exercise after orange ingestion cause anaphylaxis which is food-dependent exercise-induced anaphylaxis (FDEIA which is a form of exercise-induced anaphylaxis. In this article, an individual develops symptoms such as flushing, itching, urticaria, angioedema, and wheezing after eating a food allergen and proceeds to exercise. Neither the food alone nor exercise alone is sufficient to induce a reaction. This case report describes a 36-year-old asthmatic male athlete who experienced nausea, vomiting, flushing, urticaria, and facial swelling while exercising in a gymnasium after eating oranges. Neither oranges alone nor exercise alone induced the reaction. Total avoidance of suspected food allergens would be ideal. Persons with FDEIA should keep at hand an emergency kit with antihistamines, injectable rapid action corticoids, and adrenaline.
Consumption of Watermelon Juice Enriched in l-Citrulline and Pomegranate Ellagitannins Enhanced Metabolism during Physical Exercise.

Science.gov (United States)

Martínez-Sánchez, Ascensión; Alacid, Fernando; Rubio-Arias, Jacobo A; Fernández-Lobato, Bárbara; Ramos-Campo, Domingo J; Aguayo, Encarna

2017-06-07

l-Citrulline is a nonessential amino acid precursor of arginine and indirectly a precursor of nitric oxide (NO), which is a vasodilator and increases mitochondrial respiration. On the other hand, the antioxidant pomegranate ellagitannins are precursors of urolithin A, which has been associated with mitophagy and increased muscle function. To elucidate if a single dose of watermelon enrichment with these compounds could have a positive effect after high-intensity exercise (eight sets of eight repetitions of half-squat exercise), a double-blind randomized crossover in vivo study was performed in healthy male subjects (n = 19). Enrichment juices maintained basal levels of blood markers of muscle damage, such as lactate dehydrogenase and myoglobin, and showed a significant maintenance of force during the exercise and a significant decrease in the rating of perceived exertion and muscle soreness after exercise. A positive effect was observed between l-citrulline and ellagitannins, improving the ergogenic effect of watermelon juice.
Polymer-induced liquid precursor (PILP) phases of calcium carbonate formed in the presence of synthetic acidic polypeptides - relevance to biomineralization

NARCIS (Netherlands)

Schenk, A.S.; Zope, H.; Kim, Y.; Kros, A.; Sommerdijk, N.A.J.M.; Meldrum, F.C.

2012-01-01

Polymer-induced liquid precursor (PILP) phases of calcium carbonate have attracted significant interest due to possible applications in materials synthesis, and their resemblance to intermediates seen in biogenic mineralisation processes. Further, these PILP phases have been formed in vitro using
Exercise induces transient transcriptional activation of the PGC-1a gene in human skeletal muscle

DEFF Research Database (Denmark)

Pilegaard, Henriette; Saltin, Bengt; Neufer, P. Darrell

2003-01-01

Endurance exercise training induces mitochondrial biogenesis in skeletal muscle. The peroxisome proliferator activated receptor co-activator 1a (PGC-1a) has recently been identified as a nuclear factor critical for coordinating the activation of genes required for mitochondrial biogenesis in cell...... culture and rodent skeletal muscle. To determine whether PGC-1a transcription is regulated by acute exercise and exercise training in human skeletal muscle, seven male subjects performed 4 weeks of one-legged knee extensor exercise training. At the end of training, subjects completed 3 h of two......-legged knee extensor exercise. Biopsies were obtained from the vastus lateralis muscle of both the untrained and trained legs before exercise and after 0, 2, 6 and 24 h of recovery. Time to exhaustion (2 min maximum resistance), as well as hexokinase II (HKII), citrate synthase and 3-hydroxyacyl...
The Effect of Exercise on Learning and Spatial Memory Following Stress-Induced Sleep Deprivation (Sleep REM in Rats

Directory of Open Access Journals (Sweden)

Darkhah

2016-04-01

Full Text Available Background Stress induced by sleep deprivation can cause degradation of learning in the acquisition phase, and low-intensity exercise can prevent the negative effects of stress. Objectives The aim of this study was to investigate the moderating role of aerobic exercise on spatial memory and learning following stress-induced insomnia (sleep REM in animal models. Materials and Methods This experimental study was conducted on adult male Wistar rats that were randomly divided into two groups. Both groups were exposed to sleep deprivation induced stress, following which the experimental group was exposed to exercise training (experimental, n = 8; control, n = 8. The stress intervention was undertaken through 24 hours of sleep deprivation using a modified sleep deprivation platform (MMD. The exercise protocol included mild aerobic exercise on a treadmill (30 minutes a day, seven days, and Morris Water Maze (MWM protocols were applied to assess spatial memory and learning. Data were analyzed by an independent t-test and dependent t-test. Results The results showed that, after seven days of aerobic exercise on a treadmill, the experimental group showed better performance escape latency (P < 0.05 and distance traveled (P < 0.05 than the control group in the MWM, while there was no difference between these two groups in the pre-test. Conclusions The role of exercise is greater in the retention than the acquisition phase for recalling past experiences.
Effect of Sacubitril/Valsartan on Exercise-Induced Lipid Metabolism in Patients With Obesity and Hypertension.

Science.gov (United States)

Engeli, Stefan; Stinkens, Rudi; Heise, Tim; May, Marcus; Goossens, Gijs H; Blaak, Ellen E; Havekes, Bas; Jax, Thomas; Albrecht, Diego; Pal, Parasar; Tegtbur, Uwe; Haufe, Sven; Langenickel, Thomas H; Jordan, Jens

2018-01-01

Sacubitril/valsartan (LCZ696), a novel angiotensin receptor-neprilysin inhibitor, was recently approved for the treatment of heart failure with reduced ejection fraction. Neprilysin degrades several peptides that modulate lipid metabolism, including natriuretic peptides. In this study, we investigated the effects of 8 weeks' treatment with sacubitril/valsartan on whole-body and adipose tissue lipolysis and lipid oxidation during defined physical exercise compared with the metabolically neutral comparator amlodipine. This was a multicenter, randomized, double-blind, active-controlled, parallel-group study enrolling subjects with abdominal obesity and moderate hypertension (mean sitting systolic blood pressure ≥130-180 mm Hg). Lipolysis during rest and exercise was assessed by microdialysis and [1,1,2,3,3- 2 H]-glycerol tracer kinetics. Energy expenditure and substrate oxidation were measured simultaneously using indirect calorimetry. Plasma nonesterified fatty acids, glycerol, insulin, glucose, adrenaline and noradrenaline concentrations, blood pressure, and heart rate were also determined. Exercise elevated plasma glycerol, free fatty acids, and interstitial glycerol concentrations and increased the rate of glycerol appearance. However, exercise-induced stimulation of lipolysis was not augmented on sacubitril/valsartan treatment compared with amlodipine treatment. Furthermore, sacubitril/valsartan did not alter energy expenditure and substrate oxidation during exercise compared with amlodipine treatment. In conclusion, sacubitril/valsartan treatment for 8 weeks did not elicit clinically relevant changes in exercise-induced lipolysis or substrate oxidation in obese patients with hypertension, implying that its beneficial cardiovascular effects cannot be explained by changes in lipid metabolism during exercise. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01631864. © 2017 The Authors.
Voluntary exercise improves high-fat diet-induced leptin resistance independent of adiposity.

Science.gov (United States)

Krawczewski Carhuatanta, Kimberly A; Demuro, Giovanna; Tschöp, Matthias H; Pfluger, Paul T; Benoit, Stephen C; Obici, Silvana

2011-07-01

The efficacy of exercise as primary prevention of obesity is the subject of intense investigation. Here, we show that voluntary exercise in a mouse strain susceptible to diet-induced obesity (C57B6J) decreases fat mass and increases energy expenditure. In addition, exercise attenuates obesity in mice fed a high-fat diet (HFD). Using FosB immunoreactivity as a marker of chronic neuronal activation, we found that exercise activates leptin receptor-positive neurons in the ventromedial hypothalamic nucleus, involved in homeostatic control of energy balance. FosB immunoreactivity in the ventromedial hypothalamic nucleus is decreased in sedentary mice exposed to HFD but is increased in exercised mice independent of adiposity. To determine whether the antiobesity effects of voluntary exercise improve central nervous system (CNS) leptin action, we measured the anorectic and weight reducing effects of intracerebroventricular (ICV) leptin in sedentary and exercised mice exposed to HFD (EH), as well as in sedentary mice that have been calorie restricted (SR) to match the fat mass of EH mice. ICV leptin was ineffective in lowering food intake and body weight (BW) in sedentary mice exposed to HFD mice. The anorectic potency of leptin was partially restored in EH and SR groups. However, ICV leptin significantly lowered BW in EH but not SR mice. Thus, exercise leads to the maintenance of a lower BW and leaner composition, as well as to improved CNS leptin action, independent of fat mass. These results support the notion that physical exercise directly influences the responsiveness of the CNS circuits involved in energy homeostasis by allowing the defense of a lowered BW.
Identification of the IGF-1 processing product human Ec/rodent Eb peptide in various tissues: Evidence for its differential regulation after exercise-induced muscle damage in humans.

Science.gov (United States)

Vassilakos, George; Philippou, Anastassios; Koutsilieris, Michael

2017-02-01

Insulin-like growth factor-1 (IGF-1) is a pleiotropic factor expressed in various tissues and plays a critical role in skeletal muscle physiology. Alternative splicing of the IGF-1 gene gives rise to different precursor polypeptides (isoforms) which could undergo post-translational cleavage, generating the common mature IGF-1 peptide and different carboxyl terminal extension (E-) peptides, with the fate of the latter being, so far, unknown. The objective if this study was to identify the IGF-1Ec forms or processing product(s), other than mature IGF-1, generated in different human and rodent tissues and particularly in human skeletal muscle after exercise-induced damage. Protein lysates from a wide range of human and rodent tissues were immunoblotted with a rabbit anti-human Ec polyclonal antibody raised against the last 24 amino acids of the C-terminal of the Ec peptide. This antibody can recognize the Ec peptide, both as part of IGF-1Ec and alone, and also the corresponding rodent forms, due to the high homology that the human Ec shares with the rodent Eb. We were able to confirm, for the first time, that the human Ec peptide and its rodent homologous Eb peptide are produced simultaneously with their precursor protein (pro-IGF-1Ec/Eb) in vivo, in a wide range of tissues (e.g. muscle, liver, heart). Proprotein convertase furin digestion of human muscle and liver protein lysates confirmed that the higher molecular form, pro-IGF-1Ec, can be cleaved to produce the free Ec peptide. Furthermore, initial evidence is provided that Ec peptide is differentially regulated during the process of muscle regeneration after exercise-induced damage in humans. The findings of this study possibly imply that the post-translational modification of the IGF-1Ec pro-peptide may regulate the bioavailability and activity of the processing product(s). Copyright © 2016. Published by Elsevier Ltd.
Effect of BCAA supplement timing on exercise-induced muscle soreness and damage: a pilot placebo-controlled double-blind study.

Science.gov (United States)

Ra, Song-Gyu; Miyazaki, Teruo; Kojima, Ryo; Komine, Shoichi; Ishikura, Keisuke; Kawanaka, Kentaro; Honda, Akira; Matsuzaki, Yasushi; Ohmori, Hajime

2017-09-22

The aim of present study was to compare the effects of branched-chain amino acid (BCAA) supplementation taken before or after exercise on delayed onset muscle soreness (DOMS) and exercise-induced muscle damage (EIMD). Fifteen young men (aged 21.5 ± 0.4 years) were given either BCAA (9.6 g·day-1) or placebo before and after exercise (and for 3 days prior to and following the exercise day) in three independent groups: the Control group (placebo before and after exercise), the PRE group (BCAA before exercise and placebo after exercise), and the POST group (placebo before exercise and BCAA after exercise). Participants performed 30 repetitions of eccentric exercise with the non-dominant arm. DOMS, upper arm circumference (CIR), elbow range of motion (ROM), serum creatine kinase (CK), lactate dehydrogenase (LDH), and aldolase, BCAA, and Beta-hydroxy-Beta-methylbutyrate (3HMB) were measured immediately before and after the exercise and on the following 4 days. Serum BCAA and 3HMB concentrations increased significantly in the PRE group immediately after the exercise, recovering to baseline over the following days. In the days following the exercise day, DOMS, CIR, and ROM were significantly improved in the PRE group compared to the Control group, with weaker effects in the POST group. Serum activities of CK, LDH, and aldolase in the days following the exercise day were significantly suppressed in the PRE group compared to Control group. Present study confirmed that repeated BCAA supplementation before exercise had a more beneficial effect in attenuating DOMS and EIMD induced by eccentric exercise than repeated supplementation after exercise.
Exercise-induced rhabdomyolysis mechanisms and prevention: A literature review

Directory of Open Access Journals (Sweden)

Jooyoung Kim

2016-09-01

Full Text Available Exercise-induced rhabdomyolysis (exRML, a pathophysiological condition of skeletal muscle cell damage that may cause acute renal failure and in some cases death. Increased Ca2+ level in cells along with functional degradation of cell signaling system and cell matrix have been suggested as the major pathological mechanisms associated with exRML. The onset of exRML may be exhibited in athletes as well as in general population. Previous studies have reported that possible causes of exRML were associated with excessive eccentric contractions in high temperature, abnormal electrolytes balance, and nutritional deficiencies possible genetic defects. However, the underlying mechanisms of exRML have not been clearly established among health professionals or sports medicine personnel. Therefore, we reviewed the possible mechanisms and correlated prevention of exRML, while providing useful and practical information for the athlete and general exercising population.
More Relaxation by Deep Breath on Methacholine- Than on Exercise-Induced bronchoconstriction during the Routine Testing of Asthmatic Children

Directory of Open Access Journals (Sweden)

Iulia Ioan

2017-10-01

Full Text Available Deep inspiration (DI dilates normal airway precontracted with methacholine. The fact that this effect is diminished or absent in asthma could be explained by the presence of bronchial inflammation. The hypothesis was tested that DI induces more relaxation in methacholine induced bronchoconstriction—solely determined by the smooth muscle contraction—than in exercise induced bronchoconstriction, which is contributed to by both smooth muscle contraction and airway wall inflammation. The respiratory conductance (Grs response to DI was monitored in asthmatic children presenting a moderately positive airway response to challenge by methacholine (n = 36 or exercise (n = 37, and expressed as the post- to pre-DI Grs ratio (GrsDI. Both groups showed similar change in FEV1 after challenge and performed a DI of similar amplitude. GrsDI however was significantly larger in methacholine than in exercise induced bronchoconstriction (p < 0.02. The bronchodilatory effect of DI is thus less during exercise- than methacholine-induced bronchoconstriction. The observation is consistent with airway wall inflammation—that characterizes exercise induced bronchoconstriction—rendering the airways less responsive to DI. More generally, it is surmised that less relief of bronchoconstriction by DI is to be expected during indirect than direct airway challenge. The current suggestion that airway smooth muscle constriction and airway wall inflammation may result in opposing effects on the bronchomotor action of DI opens important perspective to the routine testing of asthmatic children. New crossover research protocols comparing the mechanical consequences of the DI maneuver are warranted during direct and indirect bronchial challenges.
Micro-structural evolution and biomineralization behavior of carbon nanofiber/bioactive glass composites induced by precursor aging time.

Science.gov (United States)

Jia, Xiaolong; Tang, Tianhong; Cheng, Dan; Zhang, Cuihua; Zhang, Ran; Cai, Qing; Yang, Xiaoping

2015-12-01

Bioactive glass (BG)-containing carbon nanofibers (CNFs) are promising orthopaedic biomaterials. Herein, CNF composites were produced from electrospinning of polyacrylonitrile (PAN)/BG sol-gel precursor solution, followed by carbonization. Choosing 58S-type BG (mol%: 58.0% SiO2-26.3% CaO-15.7% P2O5) as the model, micro-structural evolution of CNF/BG composites was systematically evaluated in relating to aging times of BG precursor solution. With aging time prolonging, BG precursors underwent morphological changes from small sol clusters with loosely and randomly branched structure to highly crosslinked Si-network structure, showing continuous increase in solution viscosity. BG precursor solution with low viscosity could mix well with PAN solution, resulting in CNF composite with homogeneously distributed BG component. Whereas, BG precursor gel with densely crosslinked Si-network structure led to uneven distribution of BG component along final CNFs due to its significant phase separation from PAN component. Meanwhile, BG nanoparticles in CNFs demonstrated micro-structural evolution that they transited from weak to strong crystal state along with longer aging time. Biomineralization in simulated body fluid and in vitro osteoblasts proliferation were then applied to determine the bioactivity of CNF/BG composites. CNF/BG composites prepared from shorter aging time could induce both faster apatite deposition and cell proliferation rate. It was suggested weakly crystallized BG nanoparticles along CNFs dissolved fast and was able to provide numerous nucleation sites for apatite deposition, which also favored the proliferation of osteoblasts cells. Aging time could thus be a useful tool to regulate the biological features of CNF/BG composites. Copyright © 2015 Elsevier B.V. All rights reserved.
Systemic Exercise-Induced Hypoalgesia Following Isometric Exercise Reduces Conditioned Pain Modulation

DEFF Research Database (Denmark)

Alsouhibani, Ali; Vaegter, Henrik Bjarke; Hoeger Bement, Marie

2018-01-01

Objective: Physically active individuals show greater conditioned pain modulation (CPM) compared with less active individuals. Understanding the effects of acute exercise on CPM may allow for a more targeted use of exercise in the management of pain. This study investigated the effects of acute...... isometric exercise on CPM. In addition, the between-session and within-session reliability of CPM was investigated. Design: Experimental, randomized crossover study. Setting: Laboratory at Marquette University. Subjects: Thirty healthy adults (19.3±1.5 years, 15 males). Methods: Subjects underwent CPM....... Results: PPTs increased during ice water immersion (i.e., CPM), and quadriceps PPT increased after exercise (P CPM decreased similarly following exercise and quiet rest (P > 0.05). CPM within-session reliability was fair to good (intraclass correlation coefficient [ICC] = 0...
Myostatin propeptide gene delivery by gene gun ameliorates muscle atrophy in a rat model of botulinum toxin-induced nerve denervation.

Science.gov (United States)

Tsai, Sen-Wei; Tung, Yu-Tang; Chen, Hsiao-Ling; Yang, Shang-Hsun; Liu, Chia-Yi; Lu, Michelle; Pai, Hui-Jing; Lin, Chi-Chen; Chen, Chuan-Mu

2016-02-01

Muscle atrophy is a common symptom after nerve denervation. Myostatin propeptide, a precursor of myostatin, has been documented to improve muscle growth. However, the mechanism underlying the muscle atrophy attenuation effects of myostatin propeptide in muscles and the changes in gene expression are not well established. We investigated the possible underlying mechanisms associated with myostatin propeptide gene delivery by gene gun in a rat denervation muscle atrophy model, and evaluated gene expression patterns. In a rat botulinum toxin-induced nerve denervation muscle atrophy model, we evaluated the effects of wild-type (MSPP) and mutant-type (MSPPD75A) of myostatin propeptide gene delivery, and observed changes in gene activation associated with the neuromuscular junction, muscle and nerve. Muscle mass and muscle fiber size was moderately increased in myostatin propeptide treated muscles (pmyostatin propeptide gene delivery, especially the mutant-type of MSPPD75A, attenuates muscle atrophy through myogenic regulatory factors and acetylcholine receptor regulation. Our data concluded that myostatin propeptide gene therapy may be a promising treatment for nerve denervation induced muscle atrophy. Copyright © 2016 Elsevier Inc. All rights reserved.

Insulin-like growth factor binding protein (IGFBP)-3 and IGFBP-5 mediate TGF-β- and myostatin-induced suppression of proliferation in porcine embryonic myogenic cell cultures

International Nuclear Information System (INIS)

Kamanga-Sollo, E.; Pampusch, M.S.; White, M.E.; Hathaway, M.R.; Dayton, W.R.

2005-01-01

We have previously shown that cultured porcine embryonic myogenic cells (PEMC) produce both insulin-like growth factor binding protein (IGFBP)-3 and IGFBP-5 and secrete these proteins into their media. Exogenously added recombinant porcine (rp) IGFBP-3 and rpIGFBP-5 act via IGF-dependent and IGF-independent mechanisms to suppress proliferation of PEMC cultures. Furthermore, immunoneutralization of endogenous IGFBP-3 and IGFBP-5 in the PEMC culture medium results in increased DNA synthesis rate suggesting that endogenous IGFBP-3 and IGFBP-5 suppress PEMC proliferation. TGF-β superfamily members myostatin and TGF-β 1 have also been shown to suppress proliferation of myogenic cells, and treatment of cultured PEMC with either TGF-β 1 or myostatin significantly (P 1 and myostatin. Here, we show that immunoneutralization of IGFBP-5 also significantly (P 1 or myostatin-treated PEMC cultures restores Long-R3-IGF-I-stimulated DNA synthesis rates to 90% of the levels observed in control cultures receiving no TGF-β 1 or myostatin treatment (P 1 or myostatin-treated PEMC cultures, phosphosmad2 levels in these cultures were not affected. These findings strongly suggest that IGFBP-3 and IGFBP-5 affect processes downstream from receptor-mediated Smad phosphorylation that facilitate the ability of TGF-β and myostatin to suppress proliferation of PEMC
Testing for Exercise-Induced Bronchoconstriction

DEFF Research Database (Denmark)

Brannan, John D; Porsbjerg, Celeste

2018-01-01

of an individual who may be at risk during a recreational sporting activity or when exercising as an occupational duty. EIB can be identified with laboratory exercise testing or surrogate tests for EIB. These include eucapnic voluntary hyperpnea and osmotic stimuli (eg, inhaled mannitol) and offer improved...
High-Intensity Exercise Induced Oxidative Stress and Skeletal Muscle Damage in Postpubertal Boys and Girls: A Comparative Study.

Science.gov (United States)

Pal, Sangita; Chaki, Biswajit; Chattopadhyay, Sreya; Bandyopadhyay, Amit

2018-04-01

Pal, S, Chaki, B, Chattopadhyay, S, and Bandyopadhyay, A. High-intensity exercise induced oxidative stress and skeletal muscle damage in post-pubertal boys and girls: a comparative study. J Strength Cond Res 32(4): 1045-1052, 2018-The purpose of this study was to examine the sex variation in high-intensity exercise induced oxidative stress and muscle damage among 44 sedentary postpubertal boys and girls through estimation of postexercise release pattern of muscle damage markers like creatine kinase, lactate dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and oxidative stress markers like extent of lipid peroxidation (thiobarbituric acid-reactive substances) and catalase activity. Muscle damage markers like creatine kinase, LDH, ALT, and AST were measured before, immediately after, and 24 and 48 hours after high-intensity incremental treadmill running. Oxidative stress markers like thiobarbituric acid-reactive substances and catalase activity were estimated before and immediately after the exercise. Lipid peroxidation and serum catalase activity increased significantly in both groups after exercise (p exercise level at 24 and 48 hours after exercise in both the sexes, (p exercise, the pattern of postexercise release of these markers were found to be similar in both the groups. Accordingly, it has been concluded from the present investigation that high-intensity exercise induces significant oxidative stress and increases indices of skeletal muscle damage in both postpubertal girls and boys. However, postpubertal girls are relatively better protected from oxidative stress and muscle damage as compared to the boys of similar age and physical activity level. It is further evident that sex difference may not be apparent for all the biomarkers of muscle damage in this age group.
Impact of endothelin blockade on acute exercise-induced changes in blood flow and endothelial function in type 2 diabetes mellitus.

Science.gov (United States)

Schreuder, Tim H A; van Lotringen, Jaap H; Hopman, Maria T E; Thijssen, Dick H J

2014-09-01

Positive vascular effects of exercise training are mediated by acute increases in blood flow. Type 2 diabetes patients show attenuated exercise-induced increases in blood flow, possibly mediated by the endothelin pathway, preventing an optimal stimulus for vascular adaptation. We examined the impact of endothelin receptor blockade (bosentan) on exercise-induced blood flow in the brachial artery and on pre- and postexercise endothelial function in type 2 diabetes patients (n = 9, 60 ± 7 years old) and control subjects (n = 10, 60 ± 5 years old). Subjects reported twice to the laboratory to perform hand-grip exercise in the presence of endothelin receptor blockade or placebo. We examined brachial artery endothelial function (via flow-mediated dilatation) before and after exercise, as well as blood flow during exercise. Endothelin receptor blockade resulted in a larger increase in blood flow during exercise in type 2 diabetes patients (P = 0.046), but not in control subjects (P = 0.309). Exercise increased shear rate across the exercise protocol, unaffected by endothelin receptor blockade. Exercise did not alter brachial artery diameter in either group, but endothelin receptor blockade resulted in a larger brachial artery diameter in type 2 diabetes patients (P = 0.033). Exercise significantly increased brachial artery flow-mediated dilatation in both groups, unaffected by endothelin receptor blockade. Endothelin receptor blockade increased exercise-induced brachial artery blood flow in type 2 diabetes patients, but not in control subjects. Despite this effect of endothelin receptor blockade on blood flow, we found no impact on baseline or post-exercise endothelial function in type 2 diabetes patients or control subjects, possibly related to normalization of the shear stimulus during exercise. The successful increase in blood flow during exercise in type 2 diabetes patients through endothelin receptor blockade may have beneficial effects in
Dietary antioxidants and exercise.

Science.gov (United States)

Powers, Scott K; DeRuisseau, Keith C; Quindry, John; Hamilton, Karyn L

2004-01-01

Muscular exercise promotes the production of radicals and other reactive oxygen species in the working muscle. Growing evidence indicates that reactive oxygen species are responsible for exercise-induced protein oxidation and contribute to muscle fatigue. To protect against exercise-induced oxidative injury, muscle cells contain complex endogenous cellular defence mechanisms (enzymatic and non-enzymatic antioxidants) to eliminate reactive oxygen species. Furthermore, exogenous dietary antioxidants interact with endogenous antioxidants to form a cooperative network of cellular antioxidants. Knowledge that exercise-induced oxidant formation can contribute to muscle fatigue has resulted in numerous investigations examining the effects of antioxidant supplementation on human exercise performance. To date, there is limited evidence that dietary supplementation with antioxidants will improve human performance. Furthermore, it is currently unclear whether regular vigorous exercise increases the need for dietary intake of antioxidants. Clearly, additional research that analyses the antioxidant requirements of individual athletes is needed.
Impact of metformin treatment and swimming exercise on visfatin levels in high-fat-induced obesity rats.

Science.gov (United States)

Gao, Ya; Wang, Changjiang; Pan, Tianrong; Luo, Li

2014-02-01

Visfatin is a recently discovered adipocytokine that contributes to glucose and obesity-related conditions. Until now, its responses to the insulin-sensitizing agent metformin and to exercise are largely unknown. We aim to investigate the impact of metformin treatment and/or swimming exercise on serum visfatin and visfatin levels in subcutaneous adipose tissue (SAT), peri-renal adipose tissue (PAT) and skeletal muscle (SM) of high-fat-induced obesity rats. Sprague-Dawley rats were fed a normal diet or a high-fat diet for 16 weeks to develop obesity model. The high-fat-induced obesity model rats were then randomized to metformin (MET), swimming exercise (SWI), or adjunctive therapy of metformin and swimming exercise (MAS), besides high-fat obesity control group and a normal control group, all with 10 rats per group. Zoometric and glycemic parameters, lipid profile, and serum visfatin levels were assessed at baseline and after 6 weeks of therapy. Visfatin levels in SAT, PAT and SM were determined by Western Blot. Metformin and swimming exercise improved lipid profile, and increased insulin sensitivity and body weight reduction were observed. Both metformin and swimming exercise down-regulated visfatin levels in SAT and PAT, while the adjunctive therapy conferred greater benefits, but no changes of visfatin levels were observed in SM. Our results indicate that visfatin down-regulation in SAT and PAT may be one of the mechanisms by which metformin and swimming exercise inhibit obesity.
The Impact of Central and Peripheral Cyclooxygenase Enzyme Inhibition on Exercise-Induced Elevations in Core Body Temperature.

NARCIS (Netherlands)

Veltmeijer, M.T.W.; Veeneman, D.; Bongers, C.C.W.G.; Netea, M.G.; Meer, J.W.M. van der; Eijsvogels, T.M.H.; Hopman, M.T.E.

2017-01-01

PURPOSE: Exercise increases core body temperature (TC) due to metabolic heat production. However, the exercise-induced release of inflammatory cytokines including interleukin-6 (IL-6) may also contribute to the rise in TC by increasing the hypothalamic temperature set point. This study investigated
Nutritional compensation to exercise- vs. diet-induced acute energy deficit in adolescents with obesity.

Science.gov (United States)

Thivel, David; Doucet, Eric; Julian, Valérie; Cardenoux, Charlotte; Boirie, Yves; Duclos, Martine

2017-07-01

To compare the energy and macronutrient intake responses to equivalent energy deficits induced by diet (food restriction) and exercise in adolescents with obesity. Fourteen 12-15years old obese adolescents completed three experimental conditions (08:00am to 07:30pm) in a randomized crossover design: i) control session (CON); ii) diet-induced 25% energy depletion (Def-EI), iii) and an exercise-induced 25% energy depletion (Def-EX). The sessions order was either CON/Def-EI/Def-EX or CON/Def-EX/Def-EI as the deficit corresponded to 25% of the energy ingested at lunch on the control day (CON) and was imposed either by exercise (Def-EX) or diet (Def-EI). Ad libitum EI and macronutrients preferences were assessed at dinner and appetite sensations assessed using visual analogue scales. Mean BMI was 36.6±5.0kg/m 2 (z-BMI: 2.40±0.29). The individually calibrated 25% energy deficit represented 254±92kcal. Ad libitum EI was significantly higher during both Def-EX (971±225kcal) and Def-EI (949±246kcal) compared with CON (742±297) (pexercise and the control session (EI Def-EX - EI CON) (r=-0,643 pexercise- or diet-induced energy deficits could lead to similar EI compensation in obese adolescents but this EI compensation might be influenced by the magnitude of the deficit. Copyright © 2016 Elsevier Inc. All rights reserved.
Should ovulation be induced in women recovering from an eating disorder or who are compulsive exercisers?

Science.gov (United States)

Abraham, S; Mira, M; Llewellyn-Jones, D

1990-03-01

The eating and exercise history of women with secondary amenorrhea and failure of ovulation using CC was studied in 14 consecutive women on a GnRH-a program. All had a history of an eating or exercise disorder. At the time of the interview, 7 women continued to have an eating or exercise disorder. There were 15 pregnancies (12 women) with 12 live births, of which 4 weighed less than 2,500 g. Infertility specialists should inquire routinely about a woman's body weight and eating and exercise behaviors, and consider treatment for these before prescribing drugs to induce ovulation.
An Examination of Exercise-Induced Feeling States and Their Association With Future Participation in Physical Activity Among Older Adults.

Science.gov (United States)

Brunet, Jennifer; Guérin, Eva; Speranzini, Nicolas

2018-01-01

Although exercise-induced feeling states may play a role in driving future behavior, their role in relation to older adults' participation in physical activity (PA) has seldom been considered. The objectives of this study were to describe changes in older adults' feeling states during exercise, and examine if levels of and changes in feeling states predicted their future participation in PA. Self-reported data on feeling states were collected from 82 older adults immediately before, during, and after a moderate-intensity exercise session, and on participation in PA 1 month later. Data were analyzed using latent growth modeling. Feelings of revitalization, positive engagement, and tranquility decreased during exercise, whereas feelings of physical exhaustion increased. Feelings of revitalization immediately before the exercise session predicted future participation in PA; changes in feeling states did not. This study does not provide empirical evidence that older adults' exercise-induced feeling states predict their future participation in PA.
Changes in corticospinal excitability during consolidation predict acute exercise-induced off-line gains in procedural memory

DEFF Research Database (Denmark)

Ostadan, Fatemeh; Centeno, Carla; Daloze, Jean-Felix

2016-01-01

A single bout of cardiovascular exercise performed immediately after practicing a motor task improves the long-term retention of the skill through an optimization of memory consolidation. However, the specific brain mechanisms underlying the effects of acute cardiovascular exercise on procedural...... exercise correlated with the magnitude of off-line gains in skill level assessed in a retention test performed 8h after motor practice. A single bout of exercise modulates short-term neuroplasticity mechanisms subserving consolidation processes that predict off-line gains in procedural memory....... memory are poorly understood. We sought to determine if a single bout of exercise modifies corticospinal excitability (CSE) during the early stages of memory consolidation. In addition, we investigated if changes in CSE are associated with exercise-induced off-line gains in procedural memory...
Ginseng administration protects skeletal muscle from oxidative stress induced by acute exercise in rats.

Science.gov (United States)

Voces, J; Cabral de Oliveira, A C; Prieto, J G; Vila, L; Perez, A C; Duarte, I D G; Alvarez, A I

2004-12-01

Enzymatic activity was analyzed in the soleus, gastrocnemius (red and white) and plantaris muscles of acutely exercised rats after long-term administration of Panax ginseng extract in order to evaluate the protective role of ginseng against skeletal muscle oxidation. Ginseng extract (3, 10, 100, or 500 mg/kg) was administered orally for three months to male Wistar rats weighing 200 +/- 50 g before exercise and to non-exercised rats (N = 8/group). The results showed a membrane stabilizing capacity of the extract since mitochondrial function measured on the basis of citrate synthase and 3-hydroxyacyl-CoA dehydrogenase activities was reduced, on average, by 20% (P < 0.05) after exercise but the activities remained unchanged in animals treated with a ginseng dose of 100 mg/kg. Glutathione status did not show significant changes after exercise or treatment. Lipid peroxidation, measured on the basis of malondialdehyde levels, was significantly higher in all muscles after exercise, and again was reduced by about 74% (P < 0.05) by the use of ginseng extract. The administration of ginseng extract was able to protect muscle from exercise-induced oxidative stress irrespective of fiber type.
Ginseng administration protects skeletal muscle from oxidative stress induced by acute exercise in rats

Directory of Open Access Journals (Sweden)

J. Voces

2004-12-01

Full Text Available Enzymatic activity was analyzed in the soleus, gastrocnemius (red and white and plantaris muscles of acutely exercised rats after long-term administration of Panax ginseng extract in order to evaluate the protective role of ginseng against skeletal muscle oxidation. Ginseng extract (3, 10, 100, or 500 mg/kg was administered orally for three months to male Wistar rats weighing 200 ± 50 g before exercise and to non-exercised rats (N = 8/group. The results showed a membrane stabilizing capacity of the extract since mitochondrial function measured on the basis of citrate synthase and 3-hydroxyacyl-CoA dehydrogenase activities was reduced, on average, by 20% (P < 0.05 after exercise but the activities remained unchanged in animals treated with a ginseng dose of 100 mg/kg. Glutathione status did not show significant changes after exercise or treatment. Lipid peroxidation, measured on the basis of malondialdehyde levels, was significantly higher in all muscles after exercise, and again was reduced by about 74% (P < 0.05 by the use of ginseng extract. The administration of ginseng extract was able to protect muscle from exercise-induced oxidative stress irrespective of fiber type.
CETP Expression Protects Female Mice from Obesity-Induced Decline in Exercise Capacity.

Science.gov (United States)

Cappel, David A; Lantier, Louise; Palmisano, Brian T; Wasserman, David H; Stafford, John M

2015-01-01

Pharmacological approaches to reduce obesity have not resulted in dramatic reductions in the risk of coronary heart disease (CHD). Exercise, in contrast, reduces CHD risk even in the setting of obesity. Cholesteryl Ester Transfer Protein (CETP) is a lipid transfer protein that shuttles lipids between serum lipoproteins and tissues. There are sexual-dimorphisms in the effects of CETP in humans. Mice naturally lack CETP, but we previously reported that transgenic expression of CETP increases muscle glycolysis in fasting and protects against insulin resistance with high-fat diet (HFD) feeding in female but not male mice. Since glycolysis provides an important energy source for working muscle, we aimed to define if CETP expression protects against the decline in exercise capacity associated with obesity. We measured exercise capacity in female mice that were fed a chow diet and then switched to a HFD. There was no difference in exercise capacity between lean, chow-fed CETP female mice and their non-transgenic littermates. Female CETP transgenic mice were relatively protected against the decline in exercise capacity caused by obesity compared to WT. Despite gaining similar fat mass after 6 weeks of HFD-feeding, female CETP mice showed a nearly two-fold increase in run distance compared to WT. After an additional 6 weeks of HFD-feeding, mice were subjected to a final exercise bout and muscle mitochondria were isolated. We found that improved exercise capacity in CETP mice corresponded with increased muscle mitochondrial oxidative capacity, and increased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). These results suggest that CETP can protect against the obesity-induced impairment in exercise capacity and may be a target to improve exercise capacity in the context of obesity.
CETP Expression Protects Female Mice from Obesity-Induced Decline in Exercise Capacity.

Directory of Open Access Journals (Sweden)

David A Cappel

Full Text Available Pharmacological approaches to reduce obesity have not resulted in dramatic reductions in the risk of coronary heart disease (CHD. Exercise, in contrast, reduces CHD risk even in the setting of obesity. Cholesteryl Ester Transfer Protein (CETP is a lipid transfer protein that shuttles lipids between serum lipoproteins and tissues. There are sexual-dimorphisms in the effects of CETP in humans. Mice naturally lack CETP, but we previously reported that transgenic expression of CETP increases muscle glycolysis in fasting and protects against insulin resistance with high-fat diet (HFD feeding in female but not male mice. Since glycolysis provides an important energy source for working muscle, we aimed to define if CETP expression protects against the decline in exercise capacity associated with obesity. We measured exercise capacity in female mice that were fed a chow diet and then switched to a HFD. There was no difference in exercise capacity between lean, chow-fed CETP female mice and their non-transgenic littermates. Female CETP transgenic mice were relatively protected against the decline in exercise capacity caused by obesity compared to WT. Despite gaining similar fat mass after 6 weeks of HFD-feeding, female CETP mice showed a nearly two-fold increase in run distance compared to WT. After an additional 6 weeks of HFD-feeding, mice were subjected to a final exercise bout and muscle mitochondria were isolated. We found that improved exercise capacity in CETP mice corresponded with increased muscle mitochondrial oxidative capacity, and increased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α. These results suggest that CETP can protect against the obesity-induced impairment in exercise capacity and may be a target to improve exercise capacity in the context of obesity.
Differential muscle regulatory factor gene expression between larval and adult myogenesis in the frog Xenopus laevis: adult myogenic cell-specific myf5 upregulation and its relation to the notochord suppression of adult muscle differentiation.

Science.gov (United States)

Yamane, Hitomi; Nishikawa, Akio

2013-08-01

During Xenopus laevis metamorphosis, larval-to-adult muscle conversion depends on the differential responses of adult and larval myogenic cells to thyroid hormone. Essential differences in cell growth, differentiation, and hormone-dependent life-or-death fate have been reported between cultured larval (tail) and adult (hindlimb) myogenic cells. A previous study revealed that tail notochord cells suppress terminal differentiation in adult (but not larval) myogenic cells. However, little is known about the differences in expression patterns of myogenic regulatory factors (MRF) and the satellite cell marker Pax7 between adult and larval myogenic cells. In the present study, we compared mRNA expression of these factors between the two types. At first, reverse transcription polymerase chain reaction analysis of hindlimb buds showed sequential upregulation of myf5, myogenin, myod, and mrf4 during stages 50-54, when limb buds elongate and muscles begin to form. By contrast, in the tail, there was no such increase during the same period. Secondary, these results were duplicated in vitro: adult myogenic cells upregulated myf5, myod, and pax7 in the early culture period, followed by myogenin upregulation and myotube differentiation, while larval myogenic cells did not upregulate these genes and precociously started myotube differentiation. Thirdly, myf5 upregulation and early-phase proliferation in adult myogenic cells were potently inhibited by the presence of notochord cells, suggesting that notochord cells suppress adult myogenesis through inhibiting the transition from Myf5(-) stem cells to Myf5(+) committed myoblasts. All of the data presented here suggest that myf5 upregulation can be a good criterion for the activation of adult myogenesis during X. laevis metamorphosis.
The Acute Effect of Local Vibration As a Recovery Modality from Exercise-Induced Increased Muscle Stiffness

Directory of Open Access Journals (Sweden)

Hervé Pournot, Jérémy Tindel, Rodolphe Testa, Laure Mathevon, Thomas Lapole

2016-03-01

Full Text Available Exercise involving eccentric muscle contractions is known to decrease range of motion and increase passive muscle stiffness. This study aimed at using ultrasound shear wave elastography to investigate acute changes in biceps brachii passive stiffness following intense barbell curl exercise involving both concentric and eccentric contractions. The effect of local vibration (LV as a recovery modality from exercise-induced increased stiffness was further investigated. Eleven subjects performed 4 bouts of 10 bilateral barbell curl movements at 70% of the one-rep maximal flexion force. An arm-to-arm comparison model was then used with one arm randomly assigned to the passive recovery condition and the other arm assigned to the LV recovery condition (10 min of 55-Hz vibration frequency and 0.9-mm amplitude. Biceps brachii shear elastic modulus measurements were performed prior to exercise (PRE, immediately after exercise (POST-EX and 5 min after the recovery period (POST-REC. Biceps brachii shear elastic modulus was significantly increased at POST-EX (+53 ± 48%; p < 0.001 and POST-REC (+31 ± 46%; p = 0.025 when compared to PRE. No differences were found between passive and LV recovery (p = 0.210. LV as a recovery strategy from exercise-induced increased muscle stiffness was not beneficial, probably due to an insufficient mechanical action of vibrations.
Myogenic Differentiation Potential of Human Newborn Foreskin Stem Cells Combined with Polycaprolactone-Based Nanofiber

Directory of Open Access Journals (Sweden)

Ozge Sezin Somuncu

2016-03-01

Full Text Available A previous study performed by the authors of the current study revealed the characterization and differentiation of newly defined stem cells known as human newborn foreskin stem cells (hnFSSCs. According to their stem cell properties, this study aimed at investigating myogenic differentiation and related tissue engineering. Human newborn foreskin stem cells were characterized by flow cytometry. The results showed that hnFSSCs carries a noble prospective for myogenic differentiation and can be used as a beneficial method for muscle related diseases, including muscular dystrophy, neuromuscular disorders, muscle damages, muscle weakness, lesion formations, and other problems associated with tissue obtainability and multi-potency; these cells may be accepted as effortlessly accessible and functional, and even superior to other stem cell origins. Furthermore, hnFFSCs were also seeded onto 3D micro-wells and Polycaprolactone (PCL scaffolds in order to examine tissue development. Human newborn foreskin stem cells on PCL scaffolds showed good cell-cell integration, so that they may be thought as a stem cell basis for tissue engineering.
Activation of Pax7-positive cells in a non-contractile tissue contributes to regeneration of myogenic tissues in the electric fish S. macrurus.

Directory of Open Access Journals (Sweden)

Christopher M Weber

Full Text Available The ability to regenerate tissues is shared across many metazoan taxa, yet the type and extent to which multiple cellular mechanisms come into play can differ across species. For example, urodele amphibians can completely regenerate all lost tissues, including skeletal muscles after limb amputation. This remarkable ability of urodeles to restore entire limbs has been largely linked to a dedifferentiation-dependent mechanism of regeneration. However, whether cell dedifferentiation is the fundamental factor that triggers a robust regeneration capacity, and whether the loss or inhibition of this process explains the limited regeneration potential in other vertebrates is not known. Here, we studied the cellular mechanisms underlying the repetitive regeneration of myogenic tissues in the electric fish S. macrurus. Our in vivo microinjection studies of high molecular weight cell lineage tracers into single identified adult myogenic cells (muscle or noncontractile muscle-derived electrocytes revealed no fragmentation or cellularization proximal to the amputation plane. In contrast, ultrastructural and immunolabeling studies verified the presence of myogenic stem cells that express the satellite cell marker Pax7 in mature muscle fibers and electrocytes of S. macrurus. These data provide the first example of Pax-7 positive muscle stem cells localized within a non-contractile electrogenic tissue. Moreover, upon amputation, Pax-7 positive cells underwent a robust replication and were detected exclusively in regions that give rise to myogenic cells and dorsal spinal cord components revealing a regeneration process in S. macrurus that is dependent on the activation of myogenic stem cells for the renewal of both skeletal muscle and the muscle-derived electric organ. These data are consistent with the emergent concept in vertebrate regeneration that different tissues provide a distinct progenitor cell population to the regeneration blastema, and these
Myogenin regulates exercise capacity but is dispensable for skeletal muscle regeneration in adult mdx mice.

Directory of Open Access Journals (Sweden)

Eric Meadows

Full Text Available Duchenne muscular dystrophy (DMD is the most prevalent inherited childhood muscle disorder in humans. mdx mice exhibit a similar pathophysiology to the human disorder allowing for an in-depth investigation of DMD. Myogenin, a myogenic regulatory factor, is best known for its role in embryonic myogenesis, but its role in adult muscle maintenance and regeneration is still poorly understood. Here, we generated an mdx:Myog(flox/flox mouse harboring a tamoxifen-inducible Cre recombinase transgene, which was used to conditionally delete Myog during adult life. After tamoxifen treatment, three groups of mice were created to study the effects of Myog deletion: mdx:Myog(flox/flox mice (mdx, Myog(flox/flox mice (wild-type, and mdx:Myog(floxΔ/floxΔ:Cre-ER mice (mdx:Myog-deleted. mdx:Myog-deleted mice exhibited no adverse phenotype and behaved normally. When run to exhaustion, mdx:Myog-deleted mice demonstrated an enhanced capacity for exercise compared to mdx mice, running nearly as far as wild-type mice. Moreover, these mice showed the same signature characteristics of muscle regeneration as mdx mice. Unexpectedly, we found that myogenin was dispensable for muscle regeneration. Factors associated with muscle fatigue, metabolism, and proteolysis were significantly altered in mdx:Myog-deleted mice, and this might contribute to their increased exercise capacity. Our results reveal novel functions for myogenin in adult muscle and suggest that reducing Myog expression in other muscle disease models may partially restore muscle function.

Alleviating exercise-induced muscular stress using neat and processed bee pollen: oxidative markers, mitochondrial enzymes, and myostatin expression in rats

Directory of Open Access Journals (Sweden)

Sameer Ketkar

2015-09-01

Conclusion: The study establishes the antioxidant, mitochondrial upregulatory, and myostatin inhibitory effects of both MIMBP and PMIMBP in exercise-induced oxidative stress conditions, suggesting their usefulness in effective management of exercise-induced muscular stress. Further, processing of MIMBP with an edible lipid-surfactant mixture was found to improve the therapeutic efficiency of pollen.
Exercise induced dyspnea in the young. Larynx as the bottleneck of the airways.

Science.gov (United States)

Røksund, Ola Drange; Maat, Robert Christiaan; Heimdal, John Helge; Olofsson, Jan; Skadberg, Britt Torunn; Halvorsen, Thomas

2009-12-01

Exercise induced asthma may symptomatically be difficult to differentiate from exercise related obstruction in the upper airways, sometimes leading to diagnostic confusion and inappropriate treatment. Larynx accounts for a significant fraction of total airway resistance, but its role as a limiting factor for airflow during exercise has been hampered by lack of diagnostic tools. We aimed to study laryngeal function in exercising humans by transnasal laryngoscopy. Continuous video recording of the larynx was performed in parallel with continuous film recording of the upper part of the body and recording of breath sounds in subjects running to respiratory distress or exhaustion on a treadmill. A successful examination was obtained in 20 asymptomatic volunteers and 151 (91%) of 166 young patients with a history of inspiratory distress or stridor during exercise. At rest, six patients had abnormal laryngeal findings. During exercise, a moderate or severe adduction of laryngeal structures was observed in parallel with increasing inspiratory distress in 113 (75%) patients. In 109 of these, adduction started within supraglottic structures, followed by adduction of the vocal cords in 88. In four patients, laryngeal adduction started in the vocal cords, involving supraglottic structures secondarily in three. Larynx can safely be studied throughout a maximum intensity exercise treadmill test. A characteristic laryngeal response pattern to exercise was visualised in a large proportion of patients with suspected upper airway obstruction. Laryngoscopy during ongoing symptoms is recommended for proper assessment of these patients.
Beneficial effect of human induced pluripotent stem cell-derived neural precursors in spinal cord injury repair

Czech Academy of Sciences Publication Activity Database

Romanyuk, Nataliya; Amemori, Takashi; Turnovcová, Karolína; Procházka, Pavel; Onteniente, B.; Syková, Eva; Jendelová, Pavla

2015-01-01

Roč. 24, č. 9 (2015), s. 1781-1797 ISSN 0963-6897 R&D Projects: GA MŠk LH12024; GA ČR(CZ) GA13-00939S; GA ČR(CZ) GBP304/12/G069; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) LO1309 Institutional support: RVO:68378041 Keywords : human induced pluripotent stem cells * neural precursors * spinal cord injury Subject RIV: FH - Neurology Impact factor: 3.427, year: 2015
The Influence of CO2 and Exercise on Hypobaric Hypoxia Induced Pulmonary Edema in Rats

Directory of Open Access Journals (Sweden)

Ryan L. Sheppard

2018-02-01

Full Text Available Introduction: Individuals with a known susceptibility to high altitude pulmonary edema (HAPE demonstrate a reduced ventilation response and increased pulmonary vasoconstriction when exposed to hypoxia. It is unknown whether reduced sensitivity to hypercapnia is correlated with increased incidence and/or severity of HAPE, and while acute exercise at altitude is known to exacerbate symptoms the effect of exercise training on HAPE susceptibility is unclear.Purpose: To determine if chronic intermittent hypercapnia and exercise increases the incidence of HAPE in rats.Methods: Male Wistar rats were randomized to sedentary (sed-air, CO2 (sed-CO2, exercise (ex-air, or exercise + CO2 (ex-CO2 groups. CO2 (3.5% and treadmill exercise (15 m/min, 10% grade were conducted on a metabolic treadmill, 1 h/day for 4 weeks. Vascular reactivity to CO2 was assessed after the training period by rheoencephalography (REG. Following the training period, animals were exposed to hypobaric hypoxia (HH equivalent to 25,000 ft for 24 h. Pulmonary injury was assessed by wet/dry weight ratio, lung vascular permeability, bronchoalveolar lavage (BAL, and histology.Results: HH increased lung wet/dry ratio (HH 5.51 ± 0.29 vs. sham 4.80 ± 0.11, P < 0.05, lung permeability (556 ± 84 u/L vs. 192 ± 29 u/L, P < 0.001, and BAL protein (221 ± 33 μg/ml vs. 114 ± 13 μg/ml, P < 0.001, white blood cell (1.16 ± 0.26 vs. 0.66 ± 0.06, P < 0.05, and platelet (16.4 ± 2.3, vs. 6.0 ± 0.5, P < 0.001 counts in comparison to normobaric normoxia. Vascular reactivity was suppressed by exercise (−53% vs. sham, P < 0.05 and exercise+CO2 (−71% vs. sham, P < 0.05. However, neither exercise nor intermittent hypercapnia altered HH-induced changes in lung wet/dry weight, BAL protein and cellular infiltration, or pulmonary histology.Conclusion: Exercise training attenuates vascular reactivity to CO2 in rats but neither exercise training nor chronic intermittent hypercapnia affect HH- induced
Exercise Training Mitigates Water Pipe Smoke Exposure-Induced Pulmonary Impairment via Inhibiting NF-κB and Activating Nrf2 Signalling Pathways

Directory of Open Access Journals (Sweden)

Abderrahim Nemmar

2018-01-01

Full Text Available Water pipe smoking is a tobacco smoking method commonly used in Eastern countries and is gaining popularity in Europe and North America, in particular among adolescents and young adults. Several clinical and experimental studies have reported that exposure to water pipe smoke (WPS induces lung inflammation and impairment of pulmonary function. However, the mechanisms of such effects are not understood, as are data on the possible palliative effect of exercise training. The present study evaluated the effects of regular aerobic exercise training (treadmill: 5 days/week, 40 min/day on subchronic exposure to WPS (30 minutes/day, 5 days/week for 2 months. C57BL/6 mice were exposed to air or WPS with or without exercise training. Airway resistance measured using forced oscillation technique was significantly and dose-dependently increased in the WPS-exposed group when compared with the air-exposed one. Exercise training significantly prevented the effect of WPS on airway resistance. Histologically, the lungs of WPS-exposed mice had focal moderate interstitial inflammatory cell infiltration consisting of neutrophil polymorphs, plasma cells, and lymphocytes. There was a mild increase in intra-alveolar macrophages and a focal damage to alveolar septae in some foci. Exercise training significantly alleviated these effects and also decreased the WPS-induced increase of tumor necrosis factor α and interleukin 6 concentrations and attenuated the increase of 8-isoprostane in lung homogenates. Likewise, the lung DNA damage induced by WPS was significantly inhibited by exercise training. Moreover, exercise training inhibited nuclear factor kappa-B (NF-κB expression induced by WPS and increased that of nuclear factor erythroid 2-related factor 2 (Nrf2. Our findings suggest that exercise training significantly mitigated WPS-induced increase in airway resistance, inflammation, oxidative stress, and DNA damage via mechanisms that include inhibiting NF-κB and
Food-dependent exercise-induced anaphylaxis in Japanese elementary school children.

Science.gov (United States)

Manabe, Tetsuharu; Oku, Norihiro; Aihara, Yukoh

2018-04-01

In 2012, we clarified that the prevalence of food-dependent exercise-induced anaphylaxis (FDEIA) was 0.018% in junior-high students in Yokohama, Japan. Furthermore, although different from FDEIA, one student who had completed oral immunotherapy developed anaphylaxis during exercise after eating causative food. There have been few large-scale epidemiological studies of FDEIA, however, in elementary school children, therefore we conducted an epidemiological study in elementary school children in Yokohama to clarify the frequency and characteristic of FDEIA. We sent a questionnaire regarding the occurrence of FDEIA to all 348 public elementary school nurses in Yokohama. We also compared the results with those for junior-high school that we previously reported. We excluded those children with a past history of immediate food allergy who had achieved desensitization status after oral immunotherapy, from FDEIA, and instead defined them as having desensitization status and exercise-induced anaphylaxis (DEIA). Of 348 school nurses, 317 responded (91.1%). Overall, eight of 170 146 children were diagnosed with FDEIA, which was significantly lower than the prevalence in junior-high school students (0.0047% vs 0.018%, P = 0.0009). The causative foods were wheat (n = 4), and soy, fruit, crustaceans, and squid (n = 1 each). Four children had DEIA and the causative foods were wheat and milk (n = 2 each). Multiple episodes occurred in five children with FDEIA and in three children with DEIA. FDEIA was far less common in elementary school than in junior-high school, and wheat was the major causative food. The new appearance of DEIA was notable. Decreasing episode recurrence remains an issue that needs to be resolved. © 2018 Japan Pediatric Society.
NOX2 Inhibition Impairs Early Muscle Gene Expression Induced by a Single Exercise Bout.

Science.gov (United States)

Henríquez-Olguín, Carlos; Díaz-Vegas, Alexis; Utreras-Mendoza, Yildy; Campos, Cristian; Arias-Calderón, Manuel; Llanos, Paola; Contreras-Ferrat, Ariel; Espinosa, Alejandra; Altamirano, Francisco; Jaimovich, Enrique; Valladares, Denisse M

2016-01-01

Reactive oxygen species (ROS) participate as signaling molecules in response to exercise in skeletal muscle. However, the source of ROS and the molecular mechanisms involved in these phenomena are still not completely understood. The aim of this work was to study the role of skeletal muscle NADPH oxidase isoform 2 (NOX2) in the molecular response to physical exercise in skeletal muscle. BALB/c mice, pre-treated with a NOX2 inhibitor, apocynin, (3 mg/kg) or vehicle for 3 days, were swim-exercised for 60 min. Phospho-p47(phox) levels were significantly upregulated by exercise in flexor digitorum brevis (FDB). Moreover, exercise significantly increased NOX2 complex assembly (p47(phox)-gp91(phox) interaction) demonstrated by both proximity ligation assay and co-immunoprecipitation. Exercise-induced NOX2 activation was completely inhibited by apocynin treatment. As expected, exercise increased the mRNA levels of manganese superoxide dismutase (MnSOD), glutathione peroxidase (GPx), citrate synthase (CS), mitochondrial transcription factor A (tfam) and interleukin-6 (IL-I6) in FDB muscles. Moreover, the apocynin treatment was associated to a reduced activation of p38 MAP kinase, ERK 1/2, and NF-κB signaling pathways after a single bout of exercise. Additionally, the increase in plasma IL-6 elicited by exercise was decreased in apocynin-treated mice compared with the exercised vehicle-group (p < 0.001). These results were corroborated using gp91-dstat in an in vitro exercise model. In conclusion, NOX2 inhibition by both apocynin and gp91dstat, alters the intracellular signaling to exercise and electrical stimuli in skeletal muscle, suggesting that NOX2 plays a critical role in molecular response to an acute exercise.
Paroxysmal Exercise-induced Dyskinesias Caused by GLUT1 Deficiency Syndrome

Directory of Open Access Journals (Sweden)

Marie Mongin

2016-03-01

Full Text Available Background: Glucose transporter type 1 deficiency syndrome is due to de novo mutations in the SLC2A1 gene encoding the glucose transporter type 1. Phenomenology Shown: Paroxysmal motor manifestations induced by exercise or fasting may be the main manifestations of glucose transporter type 1 deficiency syndrome. Educational Value: Proper identification of the paroxysmal events and early diagnosis is important since the disease is potentially treatable.
Vascular Ageing and Exercise: Focus on Cellular Reparative Processes

Directory of Open Access Journals (Sweden)

Mark D. Ross

2016-01-01

Full Text Available Ageing is associated with an increased risk of developing noncommunicable diseases (NCDs, such as diabetes and cardiovascular disease (CVD. The increased risk can be attributable to increased prolonged exposure to oxidative stress. Often, CVD is preceded by endothelial dysfunction, which carries with it a proatherothrombotic phenotype. Endothelial senescence and reduced production and release of nitric oxide (NO are associated with “vascular ageing” and are often accompanied by a reduced ability for the body to repair vascular damage, termed “reendothelialization.” Exercise has been repeatedly shown to confer protection against CVD and diabetes risk and incidence. Regular exercise promotes endothelial function and can prevent endothelial senescence, often through a reduction in oxidative stress. Recently, endothelial precursors, endothelial progenitor cells (EPC, have been shown to repair damaged endothelium, and reduced circulating number and/or function of these cells is associated with ageing. Exercise can modulate both number and function of these cells to promote endothelial homeostasis. In this review we look at the effects of advancing age on the endothelium and these endothelial precursors and how exercise appears to offset this “vascular ageing” process.
Vitamin D2 Supplementation Amplifies Eccentric Exercise-Induced Muscle Damage in NASCAR Pit Crew Athletes

Directory of Open Access Journals (Sweden)

David C. Nieman

2013-12-01

Full Text Available This study determined if 6-weeks vitamin D2 supplementation (vitD2, 3800 IU/day had an influence on muscle function, eccentric exercise-induced muscle damage (EIMD, and delayed onset of muscle soreness (DOMS in National Association for Stock Car Auto Racing (NASCAR NASCAR pit crew athletes. Subjects were randomized to vitD2 (n = 13 and placebo (n = 15, and ingested supplements (double-blind for six weeks. Blood samples were collected and muscle function tests conducted pre- and post-study (leg-back and hand grip dynamometer strength tests, body weight bench press to exhaustion, vertical jump, 30-s Wingate test. Post-study, subjects engaged in 90 min eccentric-based exercise, with blood samples and DOMS ratings obtained immediately after and 1- and 2-days post-exercise. Six weeks vitD2 increased serum 25(OHD2 456% and decreased 25(OHD3 21% versus placebo (p < 0.001, p = 0.036, respectively, with no influence on muscle function test scores. The post-study eccentric exercise bout induced EIMD and DOMS, with higher muscle damage biomarkers measured in vitD2 compared to placebo (myoglobin 252%, 122% increase, respectively, p = 0.001; creatine phosphokinase 24 h post-exercise, 169%, 32%, p < 0.001, with no differences for DOMS. In summary, 6-weeks vitD2 (3800 IU/day significantly increased 25(OHD2 and decreased 25(OHD3, had no effect on muscle function tests, and amplified muscle damage markers in NASCAR pit crew athletes following eccentric exercise.
Exercise-Induced Secretion of FGF21 and Follistatin Are Blocked by Pancreatic Clamp and Impaired in Type 2 Diabetes

DEFF Research Database (Denmark)

Hansen, Jakob Schiøler; Pedersen, Bente Klarlund; Xu, Guowang

2016-01-01

blocking the increase in the glucagon to insulin ratio. In addition, we evaluated exercise-induced plasma FGF21 and follistatin in patients with T2D compared with healthy controls in response to 1 hour of bicycle exercise followed by a 3-hour recovery period. RESULTS: In healthy individuals, we observed......CONTEXT: Hepatokines have emerged as liver-derived hormone-like factors. Plasma fibroblast growth factor (FGF)-21 and follistatin increase with a high glucagon to insulin ratio and exercise, and resting levels are elevated in patients with type 2 diabetes (T2D). OBJECTIVE: The objective...... of the study was to investigate the regulatory roles of glucagon to insulin ratio and T2D on exercise-induced FGF21 and follistatin secretion. Design /Interventions: Young healthy males performed a 2-hour bicycle exercise bout followed by 5 hours of rest in supine position with and without a pancreatic clamp...
Additive effects of physical exercise and environmental enrichment on adult hippocampal neurogenesis in mice

Directory of Open Access Journals (Sweden)

Klaus Fabel

2009-11-01

Full Text Available Voluntary physical exercise (wheel running, RUN and environmental enrichment (ENR both stimulate adult hippocampal neurogenesis but do so by different mechanisms. RUN induces precursor cell proliferation, whereas ENR exerts a survival-promoting effect on newborn cells. In addition, continued RUN prevented the physiologically occurring age-related decline in precursor cell in the dentate gyrus but did not lead to a corresponding increase in net neurogenesis. We hypothesized that in the absence of appropriate cognitive stimuli the potential for neurogenesis could not be realized but that an increased potential by proliferating precursor cells due to RUN could actually lead to more adult neurogenesis if an appropriate survival-promoting stimulus follows the exercise. We thus asked whether a sequential combination of RUN and ENR (RUNENR would show additive effects that are distinct from the application of either paradigm alone. We found that the effects of 10 days of RUN followed by 35 days of ENR were additive in that the combined stimulation yielded an approximately 30% greater increase in new neurons than either stimulus alone, which also increased neurogenesis. Surprisingly, this result indicates that although overall the amount of proliferating cells in the dentate gyrus is poorly predictive of net adult neurogenesis, an increased neurogenic potential nevertheless provides the basis for a greater efficiency of the same survival-promoting stimulus. We thus propose that physical activity can “prime” the neurogenic region of the dentate gyrus for increased neurogenesis in the case the animal is exposed to an additional cognitive stimulus, here represented by the enrichment paradigm.
Hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage.

Science.gov (United States)

Frid, Maria G; Brunetti, Jacqueline A; Burke, Danielle L; Carpenter, Todd C; Davie, Neil J; Reeves, John T; Roedersheimer, Mark T; van Rooijen, Nico; Stenmark, Kurt R

2006-02-01

Vascular remodeling in chronic hypoxic pulmonary hypertension includes marked fibroproliferative changes in the pulmonary artery (PA) adventitia. Although resident PA fibroblasts have long been considered the primary contributors to these processes, we tested the hypothesis that hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage, termed fibrocytes. Using two neonatal animal models (rats and calves) of chronic hypoxic pulmonary hypertension, we demonstrated a dramatic perivascular accumulation of mononuclear cells of a monocyte/macrophage lineage (expressing CD45, CD11b, CD14, CD68, ED1, ED2). Many of these cells produced type I collagen, expressed alpha-smooth muscle actin, and proliferated, thus exhibiting mesenchymal cell characteristics attributed to fibrocytes. The blood-borne origin of these cells was confirmed in experiments wherein circulating monocytes/macrophages of chronically hypoxic rats were in vivo-labeled with DiI fluorochrome via liposome delivery and subsequently identified in the remodeled pulmonary, but not systemic, arterial adventitia. The DiI-labeled cells that appeared in the vessel wall expressed monocyte/macrophage markers and procollagen. Selective depletion of this monocytic cell population, using either clodronate-liposomes or gadolinium chloride, prevented pulmonary adventitial remodeling (ie, production of collagen, fibronectin, and tenascin-C and accumulation of myofibroblasts). We conclude that circulating mesenchymal precursors of a monocyte/macrophage lineage, including fibrocytes, are essential contributors to hypoxia-induced pulmonary vascular remodeling.
Exercise prevented the lansoprazole-induced reduction of anti-osteoporotic efficacy of alendronate in androgen deficiency rats.

Science.gov (United States)

Cegieła, Urszula; Pytlik, Maria; Folwarczna, Joanna; Miozga, Rafał; Piskorz, Szymon; Nowak, Dorota

2014-01-01

Clinical studies indicate that proton pump inhibitors (PPIs), used long-term in elderly patients, increase the risk of osteoporotic fractures, and decrease the anti-fracture efficacy of alendronate. The aim of the present study was to examine the effect of physical exercise on the anti-osteoporotic efficacy of alendronate administered concurrently with lansoprazole, a PPI, in male rats with androgen deficiency induced by orchidectomy. Male Wistar rats at 3 months of age were divided into: sham-operated control rats, orchidectomized (ORX) control rats, ORX rats receiving alendronate, ORX rats receiving alendronate and lansoprazole, ORX rats receiving alendronate and subjected to exercise, and ORX rats receiving alendronate and lansoprazole and subjected to exercise. The orchidectomy or sham-operation was performed 7-8 days before the start of drug administration. The rats were subjected to the exercise on the treadmill 1 hour/day for 7 weeks (6 days a week). Alendronate sodium (3 mg/kg p.o.) and lansoprazole (4 mg/kg p.o.) were administered once daily for 7 weeks (6 days a week). Mechanical properties of the tibial metaphysis and femoral neck were assessed. Bone turnover markers, histomorphometric parameters, bone mass and mass of bone mineral were also studied. Lansoprazole weakened the anti-osteoporotic efficacy of alendronate. The exercise increased the alendronate effect. Similar changes were observed in the rats treated with lansoprazole and alendronate, subjected to exercise; no deleterious effects of lansoprazole were observed. In conclusion, the exercise prevented the lansoprazole-induced reduction the anti-osteoporotic efficacy of alendronate in orchidectomized rats.
Increased respiratory neural drive and work of breathing in exercise-induced laryngeal obstruction

DEFF Research Database (Denmark)

Walsted, Emil Schwarz; Faisal, Azmy; Jolley, Caroline J

2017-01-01

Rationale: Exercise induced laryngeal obstruction (EILO), a phenomenon in which the larynx closes inappropriately during physical activity, is a prevalent cause of exertional dyspnea in young individuals. The physiological ventilatory impact of EILO and its relationship to dyspnea are poorly...
Endurance exercise induces mRNA expression of oxidative enzymes in human skeletal muscle late in recovery

DEFF Research Database (Denmark)

Leick, Lotte; Plomgaard, Peter S.; Grønløkke, L.

2010-01-01

exercise. To test the hypothesis that mRNA expression of many oxidative enzymes is up-regulated late in recovery (10-24 h) after exercise, male subjects (n=8) performed a 90-min cycling exercise (70% VO(2-max)), with muscle biopsies obtained before exercise (pre), and after 10, 18 and 24 h of recovery....... The mRNA expression of carnitine-palmitoyltransferase (CPT)I, CD36, 3-hydroxyacyl-CoA-dehydrogenase (HAD), cytochrome (Cyt)c, aminolevulinate-delta-synthase (ALAS)1 and GLUT4 was 100-200% higher at 10-24 h of recovery from exercise than in a control trial. Exercise induced a 100-300% increase...... in peroxisome proliferator-activated receptor gamma co-activator (PGC)-1alpha, citrate synthase (CS), CPTI, CD36, HAD and ALAS1 mRNA contents at 10-24 h of recovery relative to before exercise. No protein changes were detected in Cytc, ALAS1 or GLUT4. This shows that mRNA expression of several training...
Exercise-induced albuminuria vs circadian variations in blood pressure in type 1 diabetes.

Science.gov (United States)

Tadida Meli, Isabelle Hota; Tankeu, Aurel T; Dehayem, Mesmin Y; Chelo, David; Noubiap, Jean Jacques N; Sobngwi, Eugene

2017-02-15

To investigated the relationship between exercise-induced ambulatory blood pressure measurement (ABPM) abnormalities in type 1 diabetes mellitus (T1DM) adolescents. We conducted a case-control at the National Obesity Center of the Yaoundé Central Hospital, Cameroon. We compared 24 h ABPM and urinary albumin-to-creatinine ratio (ACR) at rest and after a standardized treadmill exercise between 20 Cameroonian T1DM patients and 20 matched controls. T1DM adolescents were aged 12-18 years, with diabetes for at least one year, without proteinuria, with normal office blood pressure (BP) and renal function according to the general reference population. Non-diabetic controls were adolescents of general population matched for sex, age and BMI. Mean duration of diabetes was 4.2 ± 2.8 years. The mean 24 h systolic blood pressure (SBP) and diastolic blood pressure (DBP) were respectively 116 ± 9 mmHg in the diabetic group vs 111 ± 8 mmHg in the non-diabetic ( P = 0.06), and 69 ± 7 mm Hg vs 66 ± 5 mm Hg ( P = 0.19). There was no difference in the diurnal pattern of BP in diabetes patients and non-diabetic controls (SBP: 118 ± 10 mmHg vs 114 ± 10 mmHg, P = 0.11; DBP: 71 ± 7 mmHg vs 68 ± 6 mmHg, P = 0.22). Nighttime BP was higher in the diabetic group with respect to SBP (112 ± 11 mmHg vs 106 ± 7 mmHg, P = 0.06) and to the mean arterial pressure (MAP) (89 ± 9 mmHg vs 81 ± 6 mmHg, P = 0.06). ACR at rest was similar in both groups (5.5 mg/g vs 5.5 mg/g, P = 0.74), but significantly higher in diabetes patients after exercise (10.5 mg/g vs 5.5 mg/g, P = 0.03). SBP was higher in patients having exercise-induced albuminuria (116 ± 10 mmHg vs 108 ± 10 mmHg, P = 0.09). Exercise-induced albuminuria could be useful for early diagnosis of kidney damage in adolescents with T1DM.
Impact of adrenaline and metabolic stress on exercise-induced intracellular signaling and PGC-1α mRNA response in human skeletal muscle

DEFF Research Database (Denmark)

Brandt, Nina; Gunnarsson, Thomas Gunnar Petursson; Hostrup, Morten

2016-01-01

This study tested the hypothesis that elevated plasma adrenaline or metabolic stress enhances exercise-induced PGC-1α mRNA and intracellular signaling in human muscle. Trained (VO2-max: 53.8 ± 1.8 mL min(-1) kg(-1)) male subjects completed four different exercise protocols (work load of the legs...... exercise than at rest in all protocols, and higher (P adrenaline nor muscle metabolic stress determines the magnitude of PGC-1α mRNA response in human muscle. Furthermore, higher exercise-induced changes in AMPK, p38, and CREB...
Human investigations into the exercise pressor reflex

DEFF Research Database (Denmark)

Secher, Niels H; Amann, Markus

2012-01-01

During exercise, neural input from skeletal muscles reflexly maintains or elevates blood pressure (BP) despite a maybe fivefold increase in vascular conductance. This exercise pressor reflex is illustrated by similar heart rate (HR) and BP responses to electrically induced and voluntary exercise....... The importance of the exercise pressor reflex for tight cardiovascular regulation during dynamic exercise is supported by studies using pharmacological blockade of lower limb muscle afferent nerves. These experiments show attenuation of the increase in BP and cardiac output when exercise is performed...... with attenuated neural feedback. Additionally, there is no BP response to electrically induced exercise with paralysing epidural anaesthesia or when similar exercise is evoked in paraplegic patients. Furthermore, BP decreases when electrically induced exercise is carried out in tetraplegic patients. The lack...
Validation of the dyspnea index in adolescents with exercise-induced paradoxical vocal fold motion.

Science.gov (United States)

De Guzman, Vanessa; Ballif, Catherine L; Maurer, Rie; Hartnick, Christopher J; Raol, Nikhila

2014-09-01

Paradoxical vocal fold motion (PVFM) affects almost 1 million adolescents in the United States. However, to date, no disease-specific objective measure exists to assess symptom severity and response to treatment in adolescents with exercise-induced PVFM. To validate the Dyspnea Index (DI) quality-of-life instrument (previously validated for adults with breathing disorders) in children aged 12 to 18 years with exercise-induced PVFM and to determine the minimum significant DI change corresponding to patient-reported or caregiver-reported improvement or worsening of symptoms. A longitudinal study of 56 patients (age range, 12-18 years) diagnosed as having exercise-induced PVFM and their caregivers from February 1, 2013, to September 30, 2013, in an outpatient pediatric otolaryngology office practice. The DI was administered to patients and caregivers, with items modified to reflect the perspective of caregivers. Appropriate DI change was measured to reflect improvement or worsening of symptoms. Test-retest reliability was accomplished by having a subset of patients and caregivers complete the instrument twice within 2 weeks before therapy. Internal consistency was assessed by calculation of Cronbach α. Discriminant validity and convergent validity were determined by comparing DIs with assessment of global change in symptoms. The patient and caregiver mean (SD) DI changes were -12.9 (9.6) and -14.7 (9.3), respectively (P therapy.

Calorie restriction and endurance exercise share potent anti-inflammatory function in adipose tissues in ameliorating diet-induced obesity and insulin resistance in mice

Directory of Open Access Journals (Sweden)

Yan Zhen

2010-07-01

Full Text Available Abstract Background Calorie restriction (CR and endurance exercise are known to attenuate obesity and improve the metabolic syndrome. The aim of this study was to directly compare the effects of CR and endurance exercise in a mouse model of diet-induced obesity and insulin resistance. Methods Adult male C57BL/6N mice were randomly assigned and subjected to one of the six interventions for 8 weeks: low-fat diet (LC, 10% fat, low-fat diet with 30% calorie restriction (LR, high-fat diet (HC, 60% fat, high-fat diet with 30% calorie restriction (HR, high-fat diet with voluntary running exercise (HE, and high-fat diet with a combination of 30% calorie restriction and exercise (HRE. The impacts of the interventions were assessed by comprehensive metabolic analyses and pro-inflammatory cytokine gene expression. Results Endurance exercise significantly attenuated high-fat diet-induced obesity. CR dramatically prevented high-fat diet-induced metabolic abnormalities. A combination of CR and endurance exercise further reduced obesity and insulin resistance under the condition of high-fat diet. CR and endurance exercise each potently suppressed the expression of inflammatory cytokines in white adipose tissues with additive effects when combined, but the effects of diet and exercise interventions in the liver were moderate to minimal. Conclusions CR and endurance exercise share a potent anti-inflammatory function in adipose tissues in ameliorating diet-induced obesity and insulin resistance.
Exercise protects against high-fat diet-induced hypothalamic inflammation.

Science.gov (United States)

Yi, Chun-Xia; Al-Massadi, Omar; Donelan, Elizabeth; Lehti, Maarit; Weber, Jon; Ress, Chandler; Trivedi, Chitrang; Müller, Timo D; Woods, Stephen C; Hofmann, Susanna M

2012-06-25

Hypothalamic inflammation is a potentially important process in the pathogenesis of high-fat diet-induced metabolic disorders that has recently received significant attention. Microglia are macrophage-like cells of the central nervous system which are activated by pro-inflammatory signals causing local production of specific interleukins and cytokines, and these in turn may further promote systemic metabolic disease. Whether or how this microglial activation can be averted or reversed is unknown. Since running exercise improves systemic metabolic health and has been found to promote neuronal survival as well as the recovery of brain functions after injury, we hypothesized that regular treadmill running may blunt the effect of western diet on hypothalamic inflammation. Using low-density lipoprotein receptor deficient (l dlr-/-) mice to better reflect human lipid metabolism, we first confirmed that microglial activation in the hypothalamus is severely increased upon exposure to a high-fat, or "western", diet. Moderate, but regular, treadmill running exercise markedly decreased hypothalamic inflammation in these mice. Furthermore, the observed decline in microglial activation was associated with an improvement of glucose tolerance. Our findings support the hypothesis that hypothalamic inflammation can be reversed by exercise and suggest that interventions to avert or reverse neuronal damage may offer relevant potential in obesity treatment and prevention. Copyright © 2012 Elsevier Inc. All rights reserved.
Exercise-induced neuronal plasticity in central autonomic networks: role in cardiovascular control.

Science.gov (United States)

Michelini, Lisete C; Stern, Javier E

2009-09-01

more comprehensive studies aimed at understanding cellular and molecular mechanisms within CNS neuronal networks that contribute to exercise-induced neuroplasticity and cardiovascular adjustments.
Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

Directory of Open Access Journals (Sweden)

Nataliya E Chorna

Full Text Available Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN, the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ of the dentate gyrus (DG and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v. microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.
Skeletal myofiber VEGF regulates contraction-induced perfusion and exercise capacity but not muscle capillarity in adult mice.

Science.gov (United States)

Knapp, Amy E; Goldberg, Daniel; Delavar, Hamid; Trisko, Breanna M; Tang, Kechun; Hogan, Michael C; Wagner, Peter D; Breen, Ellen C

2016-07-01

A single bout of exhaustive exercise signals expression of vascular endothelial growth factor (VEGF) in the exercising muscle. Previous studies have reported that mice with life-long deletion of skeletal myofiber VEGF have fewer capillaries and a severe reduction in endurance exercise. However, in adult mice, VEGF gene deletion conditionally targeted to skeletal myofibers limits exercise capacity without evidence of capillary regression. To explain this, we hypothesized that adult skeletal myofiber VEGF acutely regulates skeletal muscle perfusion during muscle contraction. A tamoxifen-inducible skeletal myofiber-specific VEGF gene deletion mouse (skmVEGF-/-) was used to reduce skeletal muscle VEGF protein by 90% in adult mice. Three weeks after inducing deletion of the skeletal myofiber VEGF gene, skmVEGF-/- mice exhibited diminished maximum running speed (-10%, P Contraction-induced perfusion measured by optical imaging during a period of electrically stimulated muscle contraction was 85% lower in skmVEGF-/- than control mice. No evidence of capillary rarefication was detected in the soleus, gastrocnemius, and extensor digitorum longus (EDL) up to 8 wk after tamoxifen-induced VEGF ablation, and contractility and fatigue resistance of the soleus measured ex vivo were also unchanged. The force-frequency of the EDL showed a small right shift, but fatigue resistance did not differ between EDL from control and skmVEGF-/- mice. These data suggest myofiber VEGF is required for regulating perfusion during periods of contraction and may in this manner affect endurance capacity. Copyright © 2016 the American Physiological Society.
Detection of titin fragments in urine in response to exercise-induced muscle damage.

Directory of Open Access Journals (Sweden)

Kazue Kanda

Full Text Available Many studies have attempted to determine the associations between blood biomarkers and exercise-induced muscle damage. However, poor correlations between the changes in biomarker levels and the magnitude of muscle symptoms have been reported. Recent advances in proteomic tools offer a strategy for the comprehensive analysis of protein expression, which can be used to identify biomarkers. Here, we used a proteomic analysis to identify urinary proteins that appear in response to a calf-raise exercise, including repetitive eccentric muscle contractions, and found that a titin (also known as connectin N-terminal fragment molecule appears in the urine after eccentric exercise. We measured the titin fragment in urine samples from nine individuals before and after eccentric exercise using a newly-established enzyme-linked immunosorbent assay and found that the titin fragment excretion rate increased 96 h after the exercise (5.1 to 77.6 pg/min, p <0.01. The changes in the titin fragment excretion rate were correlated strongly with blood markers of muscle damage and with muscle symptoms. These findings suggest that the urinary titin fragment is potentially a noninvasive biomarker of muscle damage.
Increased respiratory neural drive and work of breathing in exercise-induced laryngeal obstruction.

Science.gov (United States)

Walsted, Emil S; Faisal, Azmy; Jolley, Caroline J; Swanton, Laura L; Pavitt, Matthew J; Luo, Yuan-Ming; Backer, Vibeke; Polkey, Michael I; Hull, James H

2018-02-01

Exercise-induced laryngeal obstruction (EILO), a phenomenon in which the larynx closes inappropriately during physical activity, is a prevalent cause of exertional dyspnea in young individuals. The physiological ventilatory impact of EILO and its relationship to dyspnea are poorly understood. The objective of this study was to evaluate exercise-related changes in laryngeal aperture on ventilation, pulmonary mechanics, and respiratory neural drive. We prospectively evaluated 12 subjects (6 with EILO and 6 healthy age- and gender-matched controls). Subjects underwent baseline spirometry and a symptom-limited incremental exercise test with simultaneous and synchronized recording of endoscopic video and gastric, esophageal, and transdiaphragmatic pressures, diaphragm electromyography, and respiratory airflow. The EILO and control groups had similar peak work rates and minute ventilation (V̇e) (work rate: 227 ± 35 vs. 237 ± 35 W; V̇e: 103 ± 20 vs. 98 ± 23 l/min; P > 0.05). At submaximal work rates (140-240 W), subjects with EILO demonstrated increased work of breathing ( P respiratory neural drive ( P respiratory mechanics and diaphragm electromyography with endoscopic video, we demonstrate, for the first time, increased work of breathing and respiratory neural drive in association with the development of EILO. Future detailed investigations are now needed to understand the role of upper airway closure in causing exertional dyspnea and exercise limitation. NEW & NOTEWORTHY Exercise-induced laryngeal obstruction is a prevalent cause of exertional dyspnea in young individuals; yet, how laryngeal closure affects breathing is unknown. In this study we synchronized endoscopic video with respiratory physiological measurements, thus providing the first detailed commensurate assessment of respiratory mechanics and neural drive in relation to laryngeal closure. Laryngeal closure was associated with increased work of breathing and respiratory neural drive preceded by an
Duration of action of formoterol and salbutamol dry-powder inhalation in prevention of exercise-induced asthma in children

DEFF Research Database (Denmark)

Daugbjerg, Peer Schrøder; Nielsen, K G; Skov, M

1996-01-01

The aim of this study was to evaluate the effect and tolerability of formoterol 12 micrograms on exercise-induced asthma in children for 12 h as compared to the effect of salbutamol 400 micrograms and placebo. The drugs were inhaled as dry powder from a flow-dependent metered-dose inhaler (DP....... Formoterol 12 micrograms administered as dry powder offers significantly better protection against exercise-induced asthma after 3 and 12 h as compared to salbutamol 400 micrograms and placebo....
NOX2 inhibition impairs early muscle gene expression induced by a single exercise bout

Directory of Open Access Journals (Sweden)

Carlos Henríquez-Olguín

2016-07-01

Full Text Available Reactive oxygen species (ROS participate as signaling molecules in response to exercise in skeletal muscle. However, the source of ROS and the molecular mechanisms involved in these phenomena are still not completely understood. The aim of this work was to study the role of skeletal muscle NADPH oxidase isoform 2 (NOX2 in the molecular response to physical exercise in skeletal muscle. BALB/c mice, pre-treated with a NOX2 inhibitor, apocynin, (3 mg/kg or vehicle for 3 days, were swim-exercised for 60 min. Phospho-p47phox levels were significantly upregulated by exercise in flexor digitorum brevis (FDB. Moreover, exercise significantly increased NOX2 complex assembly (p47phox-gp91phox interaction demonstrated by both proximity ligation assay and co-immunoprecipitation. Exercise-induced NOX2 activation was completely inhibited by apocynin treatment. As expected, exercise increased the mRNA levels of manganese superoxide dismutase (MnSOD, glutathione peroxidase (GPx, citrate synthase (CS, mitochondrial transcription factor A (tfam and interleukin-6 (IL-6 in FDB muscles. Moreover, the apocynin treatment was associated to a reduced activation of p38 MAP kinase, ERK 1/2, and NF-κB signaling pathways after a single bout of exercise. Additionally, the increase in plasma IL-6 elicited by exercise was decreased in apocynin-treated mice compared with the exercised vehicle-group (p<0.001. These results were corroborated using gp91-dstat in an in-vitro exercise model. In conclusion, NOX2 inhibition by both apocynin and gp91dstat, alters the intracellular signaling to exercise and electrical stimuli in skeletal muscle, suggesting that NOX2 plays a critical role in molecular response to an acute exercise.
High-intensity Aerobic Exercise Blocks the Facilitation of iTBS-induced Plasticity in the Human Motor Cortex.

Science.gov (United States)

Smith, Ashleigh E; Goldsworthy, Mitchell R; Wood, Fiona M; Olds, Timothy S; Garside, Tessa; Ridding, Michael C

2018-03-01

Acute exercise studies using transcranial magnetic stimulation (TMS) can provide important insights into the mechanisms underpinning the positive relationship between regular engagement in physical activity and cortical neuroplasticity. Emerging evidence indicates that a single session of aerobic exercise can promote the response to an experimentally induced suppressive neuroplasticity paradigm; however, little is known about the neuroplasticity response to facilitatory paradigms, including intermittent theta burst stimulation (iTBS). To more fully characterize the effects of exercise on brain plasticity we investigated if a single 30 min bout of high-intensity cycling (80% predicted heart rate reserve) modulated the response to an iTBS paradigm compared to rest. In 18 participants (9 females; 25.5 ± 5.0 years, range: 18-35 years) iTBS was applied using standard repetitive transcranial magnetic stimulation techniques immediately following exercise or 30 min of rest. Motor evoked potentials (MEPs) were recorded from the right first dorsal interosseous muscle at baseline, after the exercise/rest period but before iTBS, and at 5 time points following iTBS (0, 5, 10, 20 and 30 min). Contrary to our hypothesis, MEPs were suppressed following iTBS after a single 30 min bout of lower limb aerobic exercise compared to rest. These results indicate that acute aerobic exercise may not always enhance the response to an experimentally induced neuroplasticity paradigm. Further investigation of the factors that influence the relationship between exercise and neuroplasticity is warranted. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.
EXERCISE-INDUCED ASTHMA: FRESH INSIGHTS AND AN OVERVIEW

Directory of Open Access Journals (Sweden)

KHAJOTIA R

2008-01-01

Full Text Available Exercise-induced asthma (EIA is a common condition affecting 12-15% of the population. Ninety percent of asthmatic individuals and 35-45% of patients with allergic rhinitis are afflicted by EIA, while 3-10% of the general population is also believed to suffer from this condition. EIA is a condition which is more prevalent in strenuous outdoor, cold weather and winter sports. The pathophysiology of EIA continues to intrigue medical physiologists. However, the water-loss hypothesis and the post-exertional airway-rewarming hypothesis are as yet the best accepted theories. EIA is best diagnosed by a good medical history and a free-run challenge test. A post-exertion decrease by 15% in FEV1 and PEFR is diagnostic of EIA. Sensitivity of exercise testing ranges from 55% to 80% while specificity is as high as 93%. EIA is a disorder that can be successfully treated by combining both non-pharmacological and pharmacological treatment options. Prompt diagnosis and treatment of this condition is vital if we hope to provide our patients with better overall health, better social life and a better self-image.
Clinical significance of exercise-induced left ventricular wall motion abnormality occurring at a low heart rate

International Nuclear Information System (INIS)

Kimchi, A.; Rozanski, A.; Fletcher, C.; Maddahi, J.; Swan, H.J.; Berman, D.S.

1987-01-01

We studied the relationship between the heart rate at the time of onset of exercise-induced wall motion abnormality and the severity of coronary artery disease in 89 patients who underwent exercise equilibrium radionuclide ventriculography as part of their evaluation for coronary artery disease. Segmental wall motion was scored with a five-point system (3 = normal; -1 = dyskinesis); a decrease of one score defined the onset of wall motion abnormality. The onset of wall motion abnormality at less than or equal to 70% of maximal predicted heart rate had 100% predictive accuracy for coronary artery disease and higher sensitivity than the onset of ischemic ST segment depression at similar heart rate during exercise: 36% (25 of 69 patients with coronary disease) vs 19% (13 of 69 patients), p = 0.01. Wall motion abnormality occurring at less than or equal to 70% of maximal predicted heart rate was present in 49% of patients (23 of 47) with critical stenosis (greater than or equal to 90% luminal diameter narrowing), and in only 5% of patients (2 of 42) without such severe stenosis, p less than 0.001. The sensitivity of exercise-induced wall motion abnormality occurring at a low heart rate for the presence of severe coronary artery disease was similar to that of a deterioration in wall motion by more than two scores during exercise (49% vs 53%) or an absolute decrease of greater than or equal to 5% in exercise left ventricular ejection fraction (49% vs 45%)
Neurohumoral responses during prolonged exercise in humans

DEFF Research Database (Denmark)

Nybo, Lars; Nielsen, Bodil; Blomstrand, Eva

2003-01-01

This study examined neurohumoral alterations during prolonged exercise with and without hyperthermia. The cerebral oxygen-to-carbohydrate uptake ratio (O2/CHO = arteriovenous oxygen difference divided by arteriovenous glucose difference plus one-half lactate), the cerebral balances of dopamine......, and the metabolic precursor of serotonin, tryptophan, were evaluated in eight endurance-trained subjects during exercise randomized to be with or without hyperthermia. The core temperature stabilized at 37.9 +/- 0.1 degrees C (mean +/- SE) in the control trial, whereas it increased to 39.7 +/- 0.2 degrees C...... in the hyperthermic trial, with a concomitant increase in perceived exertion (P exercise trials. Both the arterial and jugular venous dopamine levels...
Exercise training prevents diastolic dysfunction induced by metabolic syndrome in rats

Directory of Open Access Journals (Sweden)

Cristiano Mostarda

2012-07-01

Full Text Available OBJECTIVE: High fructose consumption contributes to the incidence of metabolic syndrome and, consequently, to cardiovascular outcomes. We investigated whether exercise training prevents high fructose diet-induced metabolic and cardiac morphofunctional alterations. METHODS: Wistar rats receiving fructose overload (F in drinking water (100 g/l were concomitantly trained on a treadmill (FT for 10 weeks or kept sedentary. These rats were compared with a control group (C. Obesity was evaluated by the Lee index, and glycemia and insulin tolerance tests constituted the metabolic evaluation. Blood pressure was measured directly (Windaq, 2 kHz, and echocardiography was performed to determine left ventricular morphology and function. Statistical significance was determined by one-way ANOVA, with significance set at p<0.05. RESULTS: Fructose overload induced a metabolic syndrome state, as confirmed by insulin resistance (F: 3.6 ± 0.2 vs. C: 4.5 ± 0.2 mg/dl/min, hypertension (mean blood pressure, F: 118 ± 3 vs. C: 104 ± 4 mmHg and obesity (F: 0.31±0.001 vs. C: 0.29 ± 0.001 g/mm. Interestingly, fructose overload rats also exhibited diastolic dysfunction. Exercise training performed during the period of high fructose intake eliminated all of these derangements. The improvements in metabolic parameters were correlated with the maintenance of diastolic function. CONCLUSION: The role of exercise training in the prevention of metabolic and hemodynamic parameter alterations is of great importance in decreasing the cardiac morbidity and mortality related to metabolic syndrome.
Macrophages improve survival, proliferation and migration of engrafted myogenic precursor cells into MDX skeletal muscle.

Directory of Open Access Journals (Sweden)

Pierre-François Lesault

Full Text Available Transplantation of muscle precursor cells is of therapeutic interest for focal skeletal muscular diseases. However, major limitations of cell transplantation are the poor survival, expansion and migration of the injected cells. The massive and early death of transplanted myoblasts is not fully understood although several mechanisms have been suggested. Various attempts have been made to improve their survival or migration. Taking into account that muscle regeneration is associated with the presence of macrophages, which are helpful in repairing the muscle by both cleansing the debris and deliver trophic cues to myoblasts in a sequential way, we attempted in the present work to improve myoblast transplantation by coinjecting macrophages. The present data showed that in the 5 days following the transplantation, macrophages efficiently improved: i myoblast survival by limiting their massive death, ii myoblast expansion within the tissue and iii myoblast migration in the dystrophic muscle. This was confirmed by in vitro analyses showing that macrophages stimulated myoblast adhesion and migration. As a result, myoblast contribution to regenerating host myofibres was increased by macrophages one month after transplantation. Altogether, these data demonstrate that macrophages are beneficial during the early steps of myoblast transplantation into skeletal muscle, showing that coinjecting these stromal cells may be used as a helper to improve the efficiency of parenchymal cell engraftment.
Intense resistance exercise induces early and transient increases in ryanodine receptor 1 phosphorylation in human skeletal muscle.

Directory of Open Access Journals (Sweden)

Sebastian Gehlert

Full Text Available BACKGROUND: While ryanodine receptor 1 (RyR1 critically contributes to skeletal muscle contraction abilities by mediating Ca²⁺ion oscillation between sarcoplasmatic and myofibrillar compartments, AMP-activated protein kinase (AMPK senses contraction-induced energetic stress by phosphorylation at Thr¹⁷². Phosphorylation of RyR1 at serine²⁸⁴³ (pRyR1Ser²⁸⁴³ results in leaky RyR1 channels and impaired Ca²⁺homeostasis. Because acute resistance exercise exerts decreased contraction performance in skeletal muscle, preceded by high rates of Ca²⁺-oscillation and energetic stress, intense myofiber contractions may induce increased RyR1 and AMPK phosphorylation. However, no data are available regarding the time-course and magnitude of early RyR1 and AMPK phosphorylation in human myofibers in response to acute resistance exercise. PURPOSE: Determine the effects and early time-course of resistance exercise on pRyR1Ser²⁸⁴³ and pAMPKThr¹⁷² in type I and II myofibers. METHODS: 7 male subjects (age 23±2 years, height: 185±7 cm, weight: 82±5 kg performed 3 sets of 8 repetitions of maximum eccentric knee extensions. Muscle biopsies were taken at rest, 15, 30 and 60 min post exercise. pRyR1Ser²⁸⁴³ and pAMPKThr¹⁷² levels were determined by western blot and semi-quantitative immunohistochemistry techniques. RESULTS: While total RyR1 and total AMPK levels remained unchanged, RyR1 was significantly more abundant in type II than type I myofibers. pRyR1Ser²⁸⁴³ increased 15 min and peaked 30 min (p<0.01 post exercise in both myofiber types. Type I fibers showed relatively higher increases in pRyR1Ser²⁸⁴³ levels than type II myofibers and remained elevated up to 60 min post resistance exercise (p<0.05. pAMPKThr¹⁷² also increased 15 to 30 min post exercise (p<0.01 in type I and II myofibers and in whole skeletal muscle. CONCLUSION: Resistance exercise induces acutely increased pRyR1Ser²⁸⁴³ and
Endurance exercise-induced changes in BNP concentrations in cardiovascular patients versus healthy controls.

Science.gov (United States)

Aengevaeren, Vincent L; Hopman, Maria T E; Thijssen, Dick H J; van Kimmenade, Roland R; de Boer, Menko-Jan; Eijsvogels, Thijs M H

2017-01-15

Healthy athletes demonstrated increased B-type natriuretic peptide (BNP) concentrations following exercise, but it is unknown whether these responses are exaggerated in individuals with cardiovascular risk factors (CVRF) or disease (CVD). We compared exercise-induced increases in BNP between healthy controls (CON) and individuals with CVRF or CVD. Furthermore, we aimed to identify predictors for BNP responses. Serum BNP concentrations were measured in 191 participants (60±12yrs) of the Nijmegen Marches before (baseline) and immediately after 4 consecutive days of walking exercise (30-50km/day). CVRF (n=54) was defined as hypertension, hypercholesterolemia, obesity or smoking and CVD (n=55) was defined as a history of myocardial infarction, heart failure, atrial fibrillation or angina pectoris. Individuals walked 487±79min/day at 65±10% of their maximum heart rate. Baseline BNP concentrations were higher for CVD (median: 28.1pg/ml; interquartile range: 13-50, p0.05). Predictors for post-exercise BNP (R 2 =0.77) were baseline BNP, beta-blocker use and age. Prolonged moderate-intensity walking exercise increases BNP concentrations in CVD participants, but not in CVRF and CON. BNP increases were small, and did not accumulate across consecutive days of exercise. These findings suggest that prolonged walking exercise for multiple consecutive days is feasible with minimal effect on myocardial stretch, even for participants with CVD. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.
Preventive Effects of Forced Exercise against Alcohol-induced Physical Dependency and Reduction of Pain Perception Threshold

Directory of Open Access Journals (Sweden)

Majid Motaghinejad

2014-01-01

Full Text Available Background: Treatment of postabstinence syndrome of alcohol is one of the major strategies of alcoholism treatment. Exercise can be modulated major brain pathways such as a reward system and pain perception centers. The aim of this study was to evaluation the effects of forced exercise in the management of alcohol dependence and pain perception alteration which induced by alcoholism. Methods: 72 adult male rats were divided into 2 major groups: (1 40 of them was divided into groups of positive control (alcohol dependent negative control and alcohol dependent groups under treatment by forced exercise, diazepam (0.4 mg/kg and forced exercise in combination with diazepam and alcohol withdrawal signs, and blood cortisols, were measured in this groups. (2 32 rats were divided into control, alcohol dependent (without treatment, and alcohol-dependent groups under treatment by forced exercise or indometacin (5 mg/kg and then pain perception was assessed by using writhing test, tail-flick and hot plate test. Results: Forced exercise, diazepam, and their combinations significantly attenuates withdrawal syndrome to 20 ± 2, 22 ± 1.3 and 16 ± 2 and blood cortisol level to 6.8 ± 1.3,7.9 ± 1.2 and 5.8 ± 1.1, respectively, in comparison with the positive control group (P < 0.05 and P < 0.001. In alcohol dependent animal under treatment by forced exercise, pain response significantly inhibited with 37%, 57% and 38% decreases in writhing test, hot plate, and tail-flick test, respectively, in comparison with alcohol dependent (without treatment group (P < 0.05. Conclusions: This study suggested that forced exercise can be useful as adjunct therapy in alcoholism patient and also can be effective in modulation of pain threshold reduction that was induced by alcohol dependency.
Diet-induced increases in chemerin are attenuated by exercise and mediate the effect of diet on insulin and HOMA-IR

Science.gov (United States)

Lloyd, Jesse W.; Zerfass, Kristy M.; Heckstall, Ebony M.; Evans, Kristin A.

2015-01-01

Objectives: Chemerin concentrations are elevated in obesity and associated with inflammation and insulin resistance. Exercise improves insulin sensitivity, which may be facilitated by changes in chemerin. We explored the effects of chronic exercise on chemerin levels in diet-induced obese mice. Methods: We divided 40 mice into 4 groups: high-fat diet/exercise, high-fat diet/sedentary, normal diet/exercise, and normal diet/sedentary. A 9-week dietary intervention was followed by a 12-week exercise intervention (treadmill run: 11 m/min for 30 min, 3×/week). We analyzed blood samples before and after the exercise intervention. We used t-tests and linear regression to examine changes in chemerin, insulin resistance, and inflammatory markers, and associations between changes in chemerin and all other biomarkers. Results: Chemerin increased significantly across all mice over the 12-week intervention (mean ± SD = 40.7 ± 77.8%, p = 0.01), and this increase was smaller in the exercise versus sedentary mice (27.2 ± 83.9% versus 54.9 ± 70.5%, p = 0.29). The increase among the high-fat diet/exercise mice was ~44% lower than the increase among the high-fat diet/sedentary mice (55.7 ± 54.9% versus 99.8 ± 57.7%, p = 0.12). The high-fat diet mice showed significant increases in insulin (773.5 ± 1286.6%, p diet-induced increases in insulin and HOMA-IR. Conclusion: Chronic exercise may attenuate diet-driven increases in circulating chemerin, and the insulin resistance associated with a high-fat diet may be mediated by diet-induced increases in chemerin. PMID:26445641
Exercise-induced bone formation is poorly linked to local strain magnitude in the sheep tibia.

Directory of Open Access Journals (Sweden)

Ian J Wallace

Full Text Available Functional interpretations of limb bone structure frequently assume that diaphyses adjust their shape by adding bone primarily across the plane in which they are habitually loaded in order to minimize loading-induced strains. Here, to test this hypothesis, we characterize the in vivo strain environment of the sheep tibial midshaft during treadmill exercise and examine whether this activity promotes bone formation disproportionately in the direction of loading in diaphyseal regions that experience the highest strains. It is shown that during treadmill exercise, sheep tibiae were bent in an anteroposterior direction, generating maximal tensile and compressive strains on the anterior and posterior shaft surfaces, respectively. Exercise led to significantly increased periosteal bone formation; however, rather than being biased toward areas of maximal strains across the anteroposterior axis, exercise-related osteogenesis occurred primarily around the medial half of the shaft circumference, in both high and low strain regions. Overall, the results of this study demonstrate that loading-induced bone growth is not closely linked to local strain magnitude in every instance. Therefore, caution is necessary when bone shaft shape is used to infer functional loading history in the absence of in vivo data on how bones are loaded and how they actually respond to loading.

Exercise-induced ST-segment depression and myocardial ischemia in patients with hypertrophic cardiomyopathy. Myocardial scintigraphic study

International Nuclear Information System (INIS)

Miyai, Nobuyuki; Kawasaki, Tatsuya; Taniguchi, Takuya; Kamitani, Tadaaki; Kawasaki, Shingo; Sugihara, Hiroki

2005-01-01

Patients with hypertrophic cardiomyopathy (HCM) sometimes develop myocardial ischemia during exercise in the absence of coronary lesions. The relationship between myocardial ischemia and ST-segment depression was investigated during exercise testing in patients with HCM. Regional hypoperfusion and/or transient left ventricular cavity dilation, a parameter of subendocardial hypoperfusion, were assessed on exercise 99 m Tc-tetrofosmin myocardial scintigraphy in 42 patients with non-obstructive HCM. The scintigraphic results were further correlated with the ST-segment responses to exercise. Regional hypoperfusion or transient left ventricular cavity dilation were observed in 19 (45%) or 16 (38%) patients with HCM, respectively. The incidence of ST-segment depression ≥0.1 mV during exercise testing was similar in HCM patients with regional hypoperfusion, with transient left ventricular cavity dilation, and without hypoperfusion (42%, 38%, 38%, p=0.95). Furthermore, exercise-induced ST-segment depression ≥0.1 mV occurred similarly irrespective of symptoms, exercise tolerance, the degree or the site of hypertrophy, or the presence or absence of resting ST-segment depression. ST-segment depression during exercise testing was common in patients with HCM, but seems to be an unreliable marker of myocardial ischemia as assessed by exercise scintigraphy. (author)
Otolithic disease: clinical features and the role of vestibular evoked myogenic potentials.

Science.gov (United States)

Curthoys, Ian S; Manzari, Leonardo

2013-07-01

Through selective tests of the function of the canal and otolith sense organs, it is possible to assert that patient conditions are purely otolithic and that the canals are not involved. The video head impulse test selectively tests each semicircular canal; the ocular vestibular-evoked myogenic potential to 500 Hz Fz (Fz is the location on the forehead in the midline at the hairline) bone-conducted vibration (BCV) selectively tests the utricular macula and the cervical vestibular-evoked myogenic potential to 500 Hz Fz BCV selectively tests the saccular macula. The development of new specific tests of otolith function has shown that some patients may have specific deficits of just otolithic function. In the authors' experience, patients who complain strongly of postural unsteadiness should be suspected to have otolithic deficits. They may also have vertigo and in some cases have spontaneous nystagmus of peripheral origin, even though their semicircular canal function is normal. The prognosis for such patients is good. They usually appear to regain their postural stability spontaneously over weeks (or longer), even though they still have an otolithic deficit as shown by objective tests when they are free of symptoms. It is not known what procedures may accelerate the recovery of otolith function. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Diagnostic value of myocardial tomographic imaging with 123I labelled BMIPP for exercise-induced angina pectoris

International Nuclear Information System (INIS)

Wang Lijuan; Kaname Akioka; Hiroyuki Yamagishi

1999-01-01

Objective: To evaluate the diagnostic value of resting myocardial tomographic imaging with 123 I labelled BMIPP ( 123 I-BMIPP SPECT) for exercise-induced angina pectoris by comparison with stress myocardial tomographic imaging with 201 Tl( 201 Tl SPECT). Methods: 123 I-BMIPP SPECT and 201 Tl SPECT were performed in 32 patients with exercise-induced angina pectoris and 12 normal controls. Left ventricle was divided into nine segments and uptake of 201 TL and 123 I-BMIPP was evaluated by four classes score method (defect score, DS). Results: In the patients with angina pectoris, segments of 201 Tl distribution abnormality were more than that of 123 I-BMIPP. Concordant rate between DS of the 20 '1Tl SPECT for detecting coronary artery stenosis were 62%, 92% and 70%, respectively, and 201 Tl SPECT were 84%, 83% and 84%, respectively. Sensitivity of 123 I-BMIPP SPECT was significantly lower than that of 201 Tl SPECT (P 123 I-BMIPP SPECT will be. Conclusions: The results indicated that to a certain extent, resting 123 I-BMIPP SPECT may has practical clinical value for detection of coronary artery stenosis, and determination of stenotic degree in the patients with exercise-induced angina pectoris
Resveratrol Enhances Exercise-Induced Cellular and Functional Adaptations of Skeletal Muscle in Older Men and Women.

Science.gov (United States)

Alway, Stephen E; McCrory, Jean L; Kearcher, Kalen; Vickers, Austen; Frear, Benjamin; Gilleland, Diana L; Bonner, Daniel E; Thomas, James M; Donley, David A; Lively, Mathew W; Mohamed, Junaith S

2017-11-09

Older men (n = 12) and women (n = 18) 65-80 years of age completed 12 weeks of exercise and took either a placebo or resveratrol (RSV) (500 mg/d) to test the hypothesis that RSV treatment combined with exercise would increase mitochondrial density, muscle fatigue resistance, and cardiovascular function more than exercise alone. Contrary to our hypothesis, aerobic and resistance exercise coupled with RSV treatment did not reduce cardiovascular risk further than exercise alone. However, exercise added to RSV treatment improved the indices of mitochondrial density, and muscle fatigue resistance more than placebo and exercise treatments. In addition, subjects that were treated with RSV had an increase in knee extensor muscle peak torque (8%), average peak torque (14%), and power (14%) after training, whereas exercise did not increase these parameters in the placebo-treated older subjects. Furthermore, exercise combined with RSV significantly improved mean fiber area and total myonuclei by 45.3% and 20%, respectively, in muscle fibers from the vastus lateralis of older subjects. Together, these data indicate a novel anabolic role of RSV in exercise-induced adaptations of older persons and this suggests that RSV combined with exercise might provide a better approach for reversing sarcopenia than exercise alone. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Aerobic Interval Exercise Training Induces Greater Reduction in Cardiac Workload in the Recovery Period in Rats

International Nuclear Information System (INIS)

Borges, Juliana Pereira; Masson, Gustavo Santos; Tibiriçá, Eduardo; Lessa, Marcos Adriano

2014-01-01

Aerobic interval exercise training has greater benefits on cardiovascular function as compared with aerobic continuous exercise training. The present study aimed at analyzing the effects of both exercise modalities on acute and subacute hemodynamic responses of healthy rats. Thirty male rats were randomly assigned into three groups as follows: continuous exercise (CE, n = 10); interval exercise (IE, n = 10); and control (C, n = 10). Both IE and CE groups performed a 30-minute exercise session. The IE group session consisted of three successive 4-minute periods at 60% of maximal velocity (Max Vel), with 4-minute recovery intervals at 40% of Max Vel. The CE group ran continuously at 50% of Max Vel. Heart rate (HR), blood pressure(BP), and rate pressure product (RPP) were measured before, during and after the exercise session. The CE and IE groups showed an increase in systolic BP and RPP during exercise as compared with the baseline values. After the end of exercise, the CE group showed a lower response of systolic BP and RPP as compared with the baseline values, while the IE group showed lower systolic BP and mean BP values. However, only the IE group had a lower response of HR and RPP during recovery. In healthy rats, one interval exercise session, as compared with continuous exercise, induced similar hemodynamic responses during exercise. However, during recovery, the interval exercise caused greater reductions in cardiac workload than the continuous exercise
Aerobic Interval Exercise Training Induces Greater Reduction in Cardiac Workload in the Recovery Period in Rats

Science.gov (United States)

Borges, Juliana Pereira; Masson, Gustavo Santos; Tibiriçá, Eduardo; Lessa, Marcos Adriano

2014-01-01

Background Aerobic interval exercise training has greater benefits on cardiovascular function as compared with aerobic continuous exercise training. Objective The present study aimed at analyzing the effects of both exercise modalities on acute and subacute hemodynamic responses of healthy rats. Methods Thirty male rats were randomly assigned into three groups as follows: continuous exercise (CE, n = 10); interval exercise (IE, n = 10); and control (C, n = 10). Both IE and CE groups performed a 30-minute exercise session. The IE group session consisted of three successive 4-minute periods at 60% of maximal velocity (Max Vel), with 4-minute recovery intervals at 40% of Max Vel. The CE group ran continuously at 50% of Max Vel. Heart rate (HR), blood pressure(BP), and rate pressure product (RPP) were measured before, during and after the exercise session. Results The CE and IE groups showed an increase in systolic BP and RPP during exercise as compared with the baseline values. After the end of exercise, the CE group showed a lower response of systolic BP and RPP as compared with the baseline values, while the IE group showed lower systolic BP and mean BP values. However, only the IE group had a lower response of HR and RPP during recovery. Conclusion In healthy rats, one interval exercise session, as compared with continuous exercise, induced similar hemodynamic responses during exercise. However, during recovery, the interval exercise caused greater reductions in cardiac workload than the continuous exercise. PMID:24270864
Aerobic Interval Exercise Training Induces Greater Reduction in Cardiac Workload in the Recovery Period in Rats

Energy Technology Data Exchange (ETDEWEB)

Borges, Juliana Pereira, E-mail: julipborges@gmail.com; Masson, Gustavo Santos; Tibiriçá, Eduardo; Lessa, Marcos Adriano [Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro, RJ (Brazil)

2014-01-15

Aerobic interval exercise training has greater benefits on cardiovascular function as compared with aerobic continuous exercise training. The present study aimed at analyzing the effects of both exercise modalities on acute and subacute hemodynamic responses of healthy rats. Thirty male rats were randomly assigned into three groups as follows: continuous exercise (CE, n = 10); interval exercise (IE, n = 10); and control (C, n = 10). Both IE and CE groups performed a 30-minute exercise session. The IE group session consisted of three successive 4-minute periods at 60% of maximal velocity (Max Vel), with 4-minute recovery intervals at 40% of Max Vel. The CE group ran continuously at 50% of Max Vel. Heart rate (HR), blood pressure(BP), and rate pressure product (RPP) were measured before, during and after the exercise session. The CE and IE groups showed an increase in systolic BP and RPP during exercise as compared with the baseline values. After the end of exercise, the CE group showed a lower response of systolic BP and RPP as compared with the baseline values, while the IE group showed lower systolic BP and mean BP values. However, only the IE group had a lower response of HR and RPP during recovery. In healthy rats, one interval exercise session, as compared with continuous exercise, induced similar hemodynamic responses during exercise. However, during recovery, the interval exercise caused greater reductions in cardiac workload than the continuous exercise.
Physical exercise prevents cognitive impairment by enhancing hippocampal neuroplasticity and mitochondrial function in doxorubicin-induced chemobrain.

Science.gov (United States)

Park, Hye-Sang; Kim, Chang-Ju; Kwak, Hyo-Bum; No, Mi-Hyun; Heo, Jun-Won; Kim, Tae-Woon

2018-05-01

Although chemotherapy increases the survival rate of patients with various cancers, such treatment can induce acute or long-term cognitive dysfunction a phenomenon known as post-chemotherapy cognitive impairment (PCCI) or "chemobrain." Exercise is known to positively affect brain function. Thus, the present study aimed to determine whether symptoms of chemobrain and disruptions in the neuroplasticity and functioning of hippocampal mitochondria can be prevented or relieved by exercise. Wistar rats were separated into the following groups: control, control plus exercise, chemobrain, and chemobrain plus exercise. For chemobrain induction, 2 mg/kg of doxorubicin (DOX) a widely utilized chemotherapeutic agent among patients with breast cancer was dissolved in saline and directly injected to the abdomen once every 4 weeks. The exercise groups were subjected to low-intensity treadmill, 6 days per week for 4 weeks. The Morris water maze and step-down avoidance tests were conducted to evaluate cognitive function, while neuroplasticity and mitochondrial function were assessed in the hippocampus and dentate gyrus. Decreased cognitive function were observed in the chemobrain group, along with decreases in levels of neurogenesis, brain derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB), Ca 2+ retention in hippocampus. Rats of the chemobrain group also exhibited an increase in apoptosis, H 2 O 2 emission and permeability transition pore by hippocampal mitochondria. However, exercise attenuated impairments in cognitive function, neuroplasticity, and mitochondrial function induced by DOX treatment. Therefore, the findings of the present study indicate that low-intensity exercise may assist in preventing cognitive dysfunction during or after chemotherapy in patients with various cancers, including breast cancer. Copyright © 2018 Elsevier Ltd. All rights reserved.
Exercise training prevents the attenuation of anesthetic pre-conditioning-mediated cardioprotection in diet-induced obese rats.

Science.gov (United States)

Li, L; Meng, F; Li, N; Zhang, L; Wang, J; Wang, H; Li, D; Zhang, X; Dong, P; Chen, Y

2015-01-01

Obesity abolishes anesthetic pre-conditioning-induced cardioprotection due to impaired reactive oxygen species (ROS)-mediated adenosine monophosphate-activated protein kinase (AMPK) pathway, a consequence of increased basal myocardial oxidative stress. Exercise training has been shown to attenuate obesity-related oxidative stress. This study tests whether exercise training could normalize ROS-mediated AMPK pathway and prevent the attenuation of anesthetic pre-conditioning-induced cardioprotection in obesity. Male Sprague-Dawley rats were divided into lean rats fed with control diet and obese rats fed with high-fat diet. After 4 weeks of feeding, lean and obese rats were assigned to sedentary conditions or treadmill exercise for 8 weeks. There was no difference in infarct size between lean sedentary and obese sedentary rats after 25 min of myocardial ischemia followed by 120 min reperfusion. In lean rats, sevoflurane equally reduced infarct size in lean sedentary and lean exercise-trained rats. Molecular studies revealed that AMPK activity, endothelial nitric oxide synthase, and superoxide production measured at the end of ischemia in lean rats were increased in response to sevoflurane. In obese rats, sevoflurane increased the above molecular parameters and reduced infarct size in obese exercise-trained rats but not in obese sedentary rats. Additional study showed that obese exercise-trained rats had decreased basal oxidative stress than obese sedentary rats. The results indicate that exercise training can prevent the attenuation of anesthetic cardioprotection in obesity. Preventing the attenuation of this strategy may be associated with reduced basal oxidative stress and normalized ROS-mediated AMPK pathway, but the causal relationship remains to be determined. © 2014 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training

OpenAIRE

West, Daniel W. D.; Phillips, Stuart M.

2011-01-01

The purpose of this study was to investigate associations between acute exercise-induced hormone responses and adaptations to high intensity resistance training in a large cohort (n = 56) of young men. Acute post-exercise serum growth hormone (GH), free testosterone (fT), insulin-like growth factor (IGF-1) and cortisol responses were determined following an acute intense leg resistance exercise routine at the midpoint of a 12-week resistance exercise training study. Acute hormonal responses w...
Androgen interacts with exercise through the mTOR pathway to induce skeletal muscle hypertrophy.

Science.gov (United States)

Zeng, Fanxing; Zhao, Hua; Liao, Jingwen

2017-12-01

This study was designed to investigate the effects of exogenous androgen and resistance exercise on skeletal muscle hypertrophy and the role of the mammalian target of rapamycin (mTOR) signalling during the process. A total of 24 male Sprague-Dawley rats were randomly assigned to sham operation and dihydrotestosterone (DHT) implantation groups with subgroups subjected to sedentary conditions or resistance exercise (SHAM+SED, SHAM+EX, DHT+SED, and DHT+EX). The experimental procedure lasted for 10 days. The mRNA expression of androgen receptor (AR) and insulin-like growth factor I (IGF-I), the expression of myosin heavy chain (MHC), as well as the phosphorylation statuses of AR, mTOR, p70 ribosomal S6 kinase (p70 S6K ), and eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1) were determined in the white gastrocnemius muscle. The cross sectional area and wet mass of the muscle were also measured. The cross sectional area and MHC expression were significantly higher in SHAM+EX, DHT+SED, and DHT+EX than in SHAM+SED. There was no significant difference among groups in muscle mass. The mRNA expression of AR and IGF-I and the phosphorylation of mTOR, p70 S6K , and 4EBP1 were significantly increased in DHT+SED and SHAM+EX and were significantly enhanced in DHT+EX compared with either DHT or exercise alone. These data show that DHT causes hypertrophy in skeletal muscle and that exercise has a synergistic effect on DHT-induced hypertrophy. Exercise enhances androgen-induced rapid anabolic action, which involves activation of the mTOR pathway.
Exercise Training Prevents Cardiovascular Derangements Induced by Fructose Overload in Developing Rats.

Directory of Open Access Journals (Sweden)

Daniela Farah

Full Text Available The risks of chronic diseases associated with the increasing consumption of fructose-laden foods are amplified by the lack of regular physical activity and have become a serious public health issue worldwide. Moreover, childhood eating habits are strongly related to metabolic syndrome in adults. Thus, we aimed to investigate the preventive role of exercise training undertaken concurrently with a high fructose diet on cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in male rats after weaning. Male Wistar rats were divided into 4 groups (n = 8/group: Sedentary control (SC, Trained control (TC, Sedentary Fructose (SF and Trained Fructose (TF. Training was performed on a treadmill (8 weeks, 40-60% of maximum exercise test. Evaluations of cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in plasma and in left ventricle (LV were performed. Chronic fructose overload induced glucose intolerance and an increase in white adipose tissue (WAT weight, in myocardial performance index (MPI (SF:0.42±0.04 vs. SC:0.24±0.05 and in arterial pressure (SF:122±3 vs. SC:113±1 mmHg associated with increased cardiac and vascular sympathetic modulation. Fructose also induced unfavorable changes in oxidative stress profile (plasmatic protein oxidation- SF:3.30±0.09 vs. SC:1.45±0.08 nmol/mg prot; and LV total antioxidant capacity (TRAP- SF: 2.5±0.5 vs. SC:12.7±1.7 uM trolox. The TF group showed reduced WAT, glucose intolerance, MPI (0.35±0.04, arterial pressure (118±2mmHg, sympathetic modulation, plasmatic protein oxidation and increased TRAP when compared to SF group. Therefore, our findings indicate that cardiometabolic dysfunctions induced by fructose overload early in life may be prevented by moderate aerobic exercise training.
Exercise Training Prevents Cardiovascular Derangements Induced by Fructose Overload in Developing Rats

Science.gov (United States)

Farah, Daniela; Nunes, Jonas; Sartori, Michelle; Dias, Danielle da Silva; Sirvente, Raquel; Silva, Maikon B.; Fiorino, Patrícia; Morris, Mariana; Llesuy, Susana; Farah, Vera; Irigoyen, Maria-Cláudia; De Angelis, Kátia

2016-01-01

The risks of chronic diseases associated with the increasing consumption of fructose-laden foods are amplified by the lack of regular physical activity and have become a serious public health issue worldwide. Moreover, childhood eating habits are strongly related to metabolic syndrome in adults. Thus, we aimed to investigate the preventive role of exercise training undertaken concurrently with a high fructose diet on cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in male rats after weaning. Male Wistar rats were divided into 4 groups (n = 8/group): Sedentary control (SC), Trained control (TC), Sedentary Fructose (SF) and Trained Fructose (TF). Training was performed on a treadmill (8 weeks, 40–60% of maximum exercise test). Evaluations of cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in plasma and in left ventricle (LV) were performed. Chronic fructose overload induced glucose intolerance and an increase in white adipose tissue (WAT) weight, in myocardial performance index (MPI) (SF:0.42±0.04 vs. SC:0.24±0.05) and in arterial pressure (SF:122±3 vs. SC:113±1 mmHg) associated with increased cardiac and vascular sympathetic modulation. Fructose also induced unfavorable changes in oxidative stress profile (plasmatic protein oxidation- SF:3.30±0.09 vs. SC:1.45±0.08 nmol/mg prot; and LV total antioxidant capacity (TRAP)- SF: 2.5±0.5 vs. SC:12.7±1.7 uM trolox). The TF group showed reduced WAT, glucose intolerance, MPI (0.35±0.04), arterial pressure (118±2mmHg), sympathetic modulation, plasmatic protein oxidation and increased TRAP when compared to SF group. Therefore, our findings indicate that cardiometabolic dysfunctions induced by fructose overload early in life may be prevented by moderate aerobic exercise training. PMID:27930685
Vitamin D2 Supplementation Amplifies Eccentric Exercise-Induced Muscle Damage in NASCAR Pit Crew Athletes

Science.gov (United States)

Nieman, David C.; Gillitt, Nicholas D.; Shanely, R. Andrew; Dew, Dustin; Meaney, Mary Pat; Luo, Beibei

2013-01-01

This study determined if 6-weeks vitamin D2 supplementation (vitD2, 3800 IU/day) had an influence on muscle function, eccentric exercise-induced muscle damage (EIMD), and delayed onset of muscle soreness (DOMS) in National Association for Stock Car Auto Racing (NASCAR) NASCAR pit crew athletes. Subjects were randomized to vitD2 (n = 13) and placebo (n = 15), and ingested supplements (double-blind) for six weeks. Blood samples were collected and muscle function tests conducted pre- and post-study (leg-back and hand grip dynamometer strength tests, body weight bench press to exhaustion, vertical jump, 30-s Wingate test). Post-study, subjects engaged in 90 min eccentric-based exercise, with blood samples and DOMS ratings obtained immediately after and 1- and 2-days post-exercise. Six weeks vitD2 increased serum 25(OH)D2 456% and decreased 25(OH)D3 21% versus placebo (p creatine phosphokinase 24 h post-exercise, 169%, 32%, p athletes following eccentric exercise. PMID:24362707
Correlation between left ventricular filling and ischemic extent during exercise-induced myocardial ischemia

International Nuclear Information System (INIS)

Ando, Akitada; Yokota, Mitsuhiro; Iwase, Mitsunori

1993-01-01

The aim of this study was to determine how the extent of exercise-induced myocardial ischemia influence left ventricular filling. Twenty-two consecutive patients with effort angina, consisting of 16 with single vessel disease and 6 with double vessel disease, underwent exercise studies in lying and sitting positions. Extent score (ES) and severity score (SS) were calculated on polar map prepared from early exercise Tl-201 myocardial SPECT images to determine ischemic extent. Pulmonary arterial wedge pressure (PAWP), as obtained at exercise in lying position, correlated significantly well with both ES (r=0.75, p<0.001) and SS (r=0.61, p<0.01). There was, however, no significant correlation between the other hemodynamic parameters, such as heart rate, systolic pressure, rate-pressure product, cardiac index and stroke index, and both ES and SS. Either increased PAWP or ischemic extent was not dependent on the number of diseased vessels. In conclusion, the extent of increased left ventricular filling did not correlate with the number of diseased vessels, but correlated positively with ischemic extent. (N.K.)
Exercise induced renal dysfunction demonstrated both in hypertensives and normotensive controls studies by Tc-99m-DTPA

International Nuclear Information System (INIS)

Mizuiri, S.; Hayashi, I.; Ohara, T.; Hirata, K.; Sasaki, Y.

1985-01-01

It was previously reported that the hippurate transport disturbance after exercise is a specific phenomenon to patients with hypertension. The authors' study with Tc-99m-DTPA revealed exercise induced renal dysfunction not only in hypertensives (H) but also in normotensive controls (N). The details of the investigation is presented. Tc-99m-DTPA was intravenously injected at rest and during bicycle ergometric stress to 14 H and 14 N in sitting position. Serial dynamic renal images were taken, of which data were simultaneously stored in a data processor for later analysis. The renogram was drawn setting ROI on each kidney. Peak counts (PC) of vascular phase, peak time (PT) of secretory phase and radioisotope retention rate (RR) at 10 minutes were the parameters being compared between at rest and at exercise. GFR of each kidney was determined. Blood samples were obtained at rest and at the end of exercise for the measurement of aldosterone (ALD), plasma renin activity (PRA) and catecholamines (A, NA). Exercise caused significant lowering of PC, prolongation of PT and increase in RR (10 min. counts/peak counts) both in H and N. GFR (miota/min.) during exercise was significantly lower than at rest in both H (80 +- 22 vs 93.8 +- 16.9, p<0.02) and N (84 +- 17 vs 102 +- 15, p<0.01). ALD, PRA, A and NA are all elevated during exercise both in H and N. None of the rest-exercise differences significantly differed between H and N. The data indicate the exercise induced renal dysfunction demonstrated by Tc-99m-DTPA renograms is not specified to H but can also be observed in N, which may be resulted from the common changes in H and N of GFR and humoral factors
Different types of exercise induce differential effects on neuronal adaptations and memory performance.

Science.gov (United States)

Lin, Tzu-Wei; Chen, Shean-Jen; Huang, Tung-Yi; Chang, Chia-Yuan; Chuang, Jih-Ing; Wu, Fong-Sen; Kuo, Yu-Min; Jen, Chauying J

2012-01-01

Different exercise paradigms show differential effects on various forms of memory. We hypothesize that the differential effects of exercises on memory performance are caused by different neuroplasticity changes in relevant brain regions in response to different exercise trainings. We examined the effects of treadmill running (TR) and wheel running (WR) on the Pavlovian fear conditioning task that assesses learning and memory performance associated with the amygdala (cued conditioning) and both the amygdala and hippocampus (contextual conditioning). The skeletal muscle citrate synthase activity, an indicator of aerobic capacity, was elevated in rats received 4 w of TR, but not WR. While both TR and WR elevated the contextual conditional response, only TR facilitated the cued conditional response. Using a single-neuron labeling technique, we found that while both TR and MR enlarged the dendritic field and increased the spine density in hippocampal CA3 neurons, only TR showed these effects in basolateral amygdalar neurons. Moreover, both types of exercise upregulated synaptic proteins (i.e., TrkB and SNAP-25) in the hippocampus; however only TR showed similar effects in the amygdala. Injection of K252a, a TrkB kinase inhibitor, in the dorsal hippocampus or basolateral amygdala abolished the exercise-facilitated contextual or cued fear learning and memory performance, respectively, regardless of the types of exercise. In summary, our results supported that different types of exercise affect the performance of learning and memory via BDNF-TrkB signaling and neuroplasticity in specific brain regions. The brain region-specific neuronal adaptations are possibly induced by various levels of intensity/stress elicited by different types of exercise. Copyright © 2011 Elsevier Inc. All rights reserved.
Exercise induced rhabdomyolysis

Directory of Open Access Journals (Sweden)

Ružič Maja

2009-01-01

Full Text Available Introduction. Rhabdomyolysis is a potentially life threatening disease, characterized by the release of intracellular calcium from skeletal muscles and can result in acute renal failure. Case report. A nineteen year old boy was admitted to the Clinic for Infective Diseases of Clinical Center Novi Sad. The disease was developing gradually and the symptoms were dizziness, muscle pain and dark color of urine. Due to the pathological level of aminotransferase he was hospitalized on the fourth day of the disease beginning with a suspicious diagnosis of acute viral hepatitis. In the hospital course of the disease, a further elevation of serum aminotransferases, creatine kinase and lactate dehydrogenase were registered. Additional serological analyses were done to exclude other possible causes of acute liver lesion. In the neurological status prolonged decontraction of quadriceps muscle was detected and the electromyography was suspicious on neuromyositis. Conclusion. Excessive muscular activity with the strenuous exercise is the leading, but very frequently overlooked, cause of rhabdomyolysis in healthy people. Excessive physical exercise may lead to elevation of the serum activity of aminotransferases and to suspicion of hepatitis.
Exercise-induced bronchoconstriction: The effects of montelukast, a leukotriene receptor antagonist

Directory of Open Access Journals (Sweden)

James P Kemp

2009-11-01

Full Text Available James P KempClinical Professor of Pediatrics, Division of Immunology and Allergy, University of California School of Medicine, San Diego, CA, USAAbstract: Exercise-induced bronchoconstriction (EIB is very common in both patients with asthma and those who are otherwise thought to be normal. The intensity of exercise as well as the type of exercise is important in producing symptoms. This may make some types of exercise such as swimming more suitable and extended running more difficult for patients with this condition. A better understanding of EIB will allow the physician to direct the patient towards a type of exercise and medications that can result in a more active lifestyle without the same concern for resulting symptoms. This is especially important for schoolchildren who are usually enrolled in physical education classes and elite athletes who may desire to participate in competitive sports. Fortunately several medications (short- and long-acting β2-agonists, cromolyn, nedocromil, inhaled corticosteroids, and more recently leukotriene modifiers have been shown to be effective in preventing or attenuating the effects of exercise in many patients. In addition, inhaled β2-agonists have been shown to quickly reverse the airway obstruction that develops in patients and continue to be the reliever medications of choice. Inhaled corticosteroids are increasingly being recommended as regular therapy now that the role of inflammation and airway injury has been identified in EIB. With the discovery that there is a release of mediators such as histamine and leukotrienes from cells in the airway following exercise with resulting airway obstruction in susceptible individuals, interest has turned to attenuating their effects with mediator antagonists especially those that block the effects of leukotrienes. Studies with an oral leukotriene antagonist, montelukast, have shown beneficial effects in adults and children aged as young as 6 years with EIB
Dynamic proteome profiling of individual proteins in human skeletal muscle after a high-fat diet and resistance exercise.

Science.gov (United States)

Camera, Donny M; Burniston, Jatin G; Pogson, Mark A; Smiles, William J; Hawley, John A

2017-12-01

It is generally accepted that muscle adaptation to resistance exercise (REX) training is underpinned by contraction-induced, increased rates of protein synthesis and dietary protein availability. By using dynamic proteome profiling (DPP), we investigated the contribution of both synthesis and breakdown to changes in abundance on a protein-by-protein basis in human skeletal muscle. Age-matched, overweight males consumed 9 d of a high-fat, low-carbohydrate diet during which time they either undertook 3 sessions of REX or performed no exercise. Precursor enrichment and the rate of incorporation of deuterium oxide into newly synthesized muscle proteins were determined by mass spectrometry. Ninety proteins were included in the DPP, with 28 proteins exhibiting significant responses to REX. The most common pattern of response was an increase in turnover, followed by an increase in abundance with no detectable increase in protein synthesis. Here, we provide novel evidence that demonstrates that the contribution of synthesis and breakdown to changes in protein abundance induced by REX differ on a protein-by-protein basis. We also highlight the importance of the degradation of individual muscle proteins after exercise in human skeletal muscle.-Camera, D. M., Burniston, J. G., Pogson, M. A., Smiles, W. J., Hawley, J. A. Dynamic proteome profiling of individual proteins in human skeletal muscle after a high-fat diet and resistance exercise. © FASEB.

Regular voluntary exercise cures stress-induced impairment of cognitive function and cell proliferation accompanied by increases in cerebral IGF-1 and GST activity in mice.

Science.gov (United States)

Nakajima, Sanae; Ohsawa, Ikuroh; Ohta, Shigeo; Ohno, Makoto; Mikami, Toshio

2010-08-25

Chronic stress impairs cognitive function and hippocampal neurogenesis. This impairment is attributed to increases in oxidative stress, which result in the accumulation of lipid peroxide. On the other hand, voluntary exercise enhances cognitive function, hippocampal neurogenesis, and antioxidant capacity in normal animals. However, the effects of voluntary exercise on cognitive function, neurogenesis, and antioxidants in stressed mice are unclear. This study was designed to investigate whether voluntary exercise cures stress-induced impairment of cognitive function accompanied by improvement of hippocampal neurogenesis and increases in antioxidant capacity. Stressed mice were exposed to chronic restraint stress (CRS), which consisted of 12h immobilization daily and feeding in a small cage, for 8 weeks. Exercised mice were allowed free access to a running wheel during their exposure to CRS. At the 6th week, cognitive function was examined using the Morris water maze (MWM) test. Daily voluntary exercise restored stress-induced impairment of cognitive function and the hippocampal cell proliferation of newborn cells but not cell survival. Voluntary exercise increased insulin-like growth factor 1 (IGF-1) protein and mRNA expression in the cerebral cortex and liver, respectively. In addition, CRS resulted in a significant increase in the number of 4-hydrosynonenal (4-HNE)-positive cells in the hippocampal dentate gyrus; whereas, voluntary exercise inhibited it and enhanced glutathione s-transferases (GST) activity in the brain. These findings suggest that voluntary exercise attenuated the stress-induced impairment of cognitive function accompanied by improvement of cell proliferation in the dentate gyrus. This exercise-induced improvement was attributed to exercise-induced enhancement of IGF-1 protein and GST activity in the brain. Copyright 2010 Elsevier B.V. All rights reserved.
[Silent myocardial ischemia and exercise-induced arrhythmia detected by the exercise test in the total health promotion plan (THP)].

Science.gov (United States)

Iwane, M; Shibe, Y; Itoh, K; Kinoshita, F; Kanagawa, Y; Kobayashi, M; Mugitani, K; Ohta, M; Ohata, H; Yoshikawa, A; Ikuta, Z; Nakamura, Y; Mohara, O

2001-03-01

We investigated the prevalence and characteristics of ischemic heart disease especially silent myocardial ischemia (SMI) and arrhythmia in need of careful observation in the exercise stress tests in the Total Health Promotion Plan (THP), which was conducted between 1994-96 for the purpose of measuring cardiopulmonary function. All workers (n = 4,918, 4,426 males) aged 18-60 yr old in an occupational field were studied. Exercise tests with an ergometer were performed by the LOPS protocol, in which the maximal workload was set up as a presumed 70-80% maximal oxygen intake, or STEP (original multistage protocol). ECG changes were evaluated with a CC5 lead. Two hundred and fifteen people refused the study because of a common cold, lumbago and so on. Of 4,703 subjects, 17 with abnormal rest ECG and 19 with probable anginal pain were excluded from the exercise tests. Of 4,667 who underwent the exercise test, 37 (0.79%) had ischemic ECG change, and 155 (3.32%) had striking arrhythmia. These 228 subjects then did a treadmill exercise test with Bruce protocol. Twenty-two (0.47% of 4,703) showed positive ECG change, 9 (0.19%) of 22 had abnormal findings on a 201Tl scan. 8 (0.17%) were diagnosed as SMI (Cohn I), in which the prevalence of hypertension, hyperlipidemia, diabetes mellitus, smoker and positive familial history of ischemic heart disease was greater than that of all subjects. In a 15-30 month follow up, none has developed cardiac accidents. Exercise-induced arrhythmia was detected in 11 (0.23%) subjects. Four were non-sustained ventricular tachycardia without any organic disease, 4 were ventricular arrhythmia based on cardiomyopathy detected by echocardiography, 2 were atrial fibrillation and another was WPW syndrome. It is therefore likely that the ergometer exercise test in THP was effective in preventing sudden death caused by ischemic heart disease or striking arrhythmia.
Dietary Supplementation with the Microalga Galdieria sulphuraria (Rhodophyta Reduces Prolonged Exercise-Induced Oxidative Stress in Rat Tissues

Directory of Open Access Journals (Sweden)

Simona Carfagna

2015-01-01

Full Text Available We studied the effects of ten-day 1% Galdieria sulphuraria dietary supplementation on oxidative damage and metabolic changes elicited by acute exercise (6-hour swimming determining oxygen consumption, lipid hydroperoxides, protein bound carbonyls in rat tissue (liver, heart, and muscle homogenates and mitochondria, tissue glutathione peroxidase and glutathione reductase activities, glutathione content, and rates of H2O2 mitochondrial release. Exercise increased oxidative damage in tissues and mitochondria and decreased tissue content of reduced glutathione. Moreover, it increased State 4 and decreased State 3 respiration in tissues and mitochondria. G. sulphuraria supplementation reduced the above exercise-induced variations. Conversely, alga supplementation was not able to modify the exercise-induced increase in mitochondrial release rate of hydrogen peroxide and in liver and heart antioxidant enzyme activities. The alga capacity to reduce lipid oxidative damage without reducing mitochondrial H2O2 release can be due to its high content of C-phycocyanin and glutathione, which are able to scavenge peroxyl radicals and contribute to phospholipid hydroperoxide metabolism, respectively. In conclusion, G. sulphuraria ability to reduce exercise-linked oxidative damage and mitochondrial dysfunction makes it potentially useful even in other conditions leading to oxidative stress, including hyperthyroidism, chronic inflammation, and ischemia/reperfusion.
Dietary supplementation with the microalga Galdieria sulphuraria (Rhodophyta) reduces prolonged exercise-induced oxidative stress in rat tissues.

Science.gov (United States)

Carfagna, Simona; Napolitano, Gaetana; Barone, Daniela; Pinto, Gabriele; Pollio, Antonino; Venditti, Paola

2015-01-01

We studied the effects of ten-day 1% Galdieria sulphuraria dietary supplementation on oxidative damage and metabolic changes elicited by acute exercise (6-hour swimming) determining oxygen consumption, lipid hydroperoxides, protein bound carbonyls in rat tissue (liver, heart, and muscle) homogenates and mitochondria, tissue glutathione peroxidase and glutathione reductase activities, glutathione content, and rates of H2O2 mitochondrial release. Exercise increased oxidative damage in tissues and mitochondria and decreased tissue content of reduced glutathione. Moreover, it increased State 4 and decreased State 3 respiration in tissues and mitochondria. G. sulphuraria supplementation reduced the above exercise-induced variations. Conversely, alga supplementation was not able to modify the exercise-induced increase in mitochondrial release rate of hydrogen peroxide and in liver and heart antioxidant enzyme activities. The alga capacity to reduce lipid oxidative damage without reducing mitochondrial H2O2 release can be due to its high content of C-phycocyanin and glutathione, which are able to scavenge peroxyl radicals and contribute to phospholipid hydroperoxide metabolism, respectively. In conclusion, G. sulphuraria ability to reduce exercise-linked oxidative damage and mitochondrial dysfunction makes it potentially useful even in other conditions leading to oxidative stress, including hyperthyroidism, chronic inflammation, and ischemia/reperfusion.
Exercise-induced hypertension in men with metabolic syndrome: anthropometric, metabolic, and hemodynamic features.

Science.gov (United States)

Gaudreault, Valérie; Després, Jean-Pierre; Rhéaume, Caroline; Alméras, Natalie; Bergeron, Jean; Tremblay, Angelo; Poirier, Paul

2013-02-01

Metabolic syndrome is associated with increased cardiac morbidity. The aim of this study was to evaluate exercise-induced hypertension (EIH) in men with metabolic syndrome and to explore potential associations with anthropometric and metabolic variables. A total of 179 normotensive men with metabolic syndrome underwent a maximal symptom-limited treadmill test. Blood pressure was measured at 5-min rest prior to exercise testing (anticipatory blood pressure), at every 3 min during the exercise, and during the recovery period. EIH was defined as maximum systolic blood pressure (SBP) ≥220 mmHg and/or maximum diastolic blood pressure (DBP) ≥100 mmHg. Of the 179 men, 87 (47%) presented EIH. Resting blood pressure values at baseline were 127±10/83±6 mmHg in EIH and 119±9/80±6 mmHg (P=0.01 for both) in normal blood pressure responders to exercise. Anticipatory SBP and DPS were higher in the group with EIH (P=0.001). Subjects with EIH presented higher waist circumference (WC) (Pmetabolic syndrome showed EIH. These men are characterized by a worsened metabolic profile. Our data suggest that a treadmill exercise test may be helpful to identify a potentially higher risk metabolic syndrome subset of subjects.
Supplementation with beta-hydroxy-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) reduces signs and symptoms of exercise-induced muscle damage in man.

Science.gov (United States)

van Someren, Ken A; Edwards, Adam J; Howatson, Glyn

2005-08-01

This study examined the effects of beta-hydroxyl-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) supplementation on signs and symptoms of exercise-induced muscle damage following a single bout of eccentrically biased resistance exercise. Six non-resistance trained male subjects performed an exercise protocol designed to induce muscle damage on two separate occasions, performed on the dominant or non-dominant arm in a counter-balanced crossover design. Subjects were assigned to an HMB/KIC (3 g HMB and 0.3 g alpha-ketoisocaproic acid, daily) or placebo treatment for 14 d prior to exercise in the counter-balanced crossover design. One repetition maximum (1RM), plasma creatine kinase activity (CK), delayed onset muscle soreness (DOMS), limb girth, and range of motion (ROM) were determined pre-exercise, at 1h, 24 h, 48 h, and 72 h post-exercise. DOMS and the percentage changes in 1RM, limb girth, and ROM all changed over the 72 h period (P HMB//IC supplementation attenuated the CK response, the percentage decrement in 1RM, and the percentage increase in limb girth (P HMB/KIC treatment. In conclusion, 14 d of HMB and KIC supplementation reduced signs and symptoms of exercise-induced muscle damage in non-resistance trained males following a single bout of eccentrically biased resistance exercise.
Bistable switches control memory and plasticity in cellular differentiation

Science.gov (United States)

Wang, Lei; Walker, Brandon L.; Iannaccone, Stephen; Bhatt, Devang; Kennedy, Patrick J.; Tse, William T.

2009-01-01

Development of stem and progenitor cells into specialized tissues in multicellular organisms involves a series of cell fate decisions. Cellular differentiation in higher organisms is generally considered irreversible, and the idea of developmental plasticity in postnatal tissues is controversial. Here, we show that inhibition of mitogen-activated protein kinase (MAPK) in a human bone marrow stromal cell-derived myogenic subclone suppresses their myogenic ability and converts them into satellite cell-like precursors that respond to osteogenic stimulation. Clonal analysis of the induced osteogenic response reveals ultrasensitivity and an “all-or-none” behavior, hallmarks of a bistable switch mechanism with stochastic noise. The response demonstrates cellular memory, which is contingent on the accumulation of an intracellular factor and can be erased by factor dilution through cell divisions or inhibition of protein synthesis. The effect of MAPK inhibition also exhibits memory and appears to be controlled by another bistable switch further upstream that determines cell fate. Once the memory associated with osteogenic differentiation is erased, the cells regain their myogenic ability. These results support a model of cell fate decision in which a network of bistable switches controls inducible production of lineage-specific differentiation factors. A competitive balance between these factors determines cell fate. Our work underscores the dynamic nature of cellular differentiation and explains mechanistically the dual properties of stability and plasticity associated with the process. PMID:19366677
Metabolomics approach for analyzing the effects of exercise in subjects with type 1 diabetes mellitus.

Directory of Open Access Journals (Sweden)

Laura Brugnara

Full Text Available The beneficial effects of exercise in patients with type 1 diabetes (T1D are not fully proven, given that it may occasionally induce acute metabolic disturbances. Indeed, the metabolic disturbances associated with sustained exercise may lead to worsening control unless great care is taken to adjust carbohydrate intake and insulin dosage. In this work, pre- and post-exercise metabolites were analyzed using a (1H-NMR and GC-MS untargeted metabolomics approach assayed in serum. We studied ten men with T1D and eleven controls matched for age, body mass index, body fat composition, and cardiorespiratory capacity, participated in the study. The participants performed 30 minutes of exercise on a cycle-ergometer at 80% VO(2max. In response to exercise, both groups had increased concentrations of gluconeogenic precursors (alanine and lactate and tricarboxylic acid cycle intermediates (citrate, malate, fumarate and succinate. The T1D group, however, showed attenuation in the response of these metabolites to exercise. Conversely to T1D, the control group also presented increases in α-ketoglutarate, alpha-ketoisocaproic acid, and lipolysis products (glycerol and oleic and linoleic acids, as well as a reduction in branched chain amino acids (valine and leucine determinations. The T1D patients presented a blunted metabolic response to acute exercise as compared to controls. This attenuated response may interfere in the healthy performance or fitness of T1D patients, something that further studies should elucidate.
Voluntary Exercise Prevents Cisplatin-Induced Muscle Wasting during Chemotherapy in Mice

DEFF Research Database (Denmark)

Hojman, Pernille; Fjelbye, Jonas; Zerahn, Bo

2014-01-01

, food intake as well as muscle mass, strength and signalling. Mice were treated weekly with 4 mg/kg cisplatin or saline for 6 weeks, and randomized to voluntary wheel running or not. Cisplatin treatment induced loss of body weight (29.8%, P ... as anorexia, impaired muscle strength (22.5% decrease, P wheel running during treatment attenuated body weight...... loss by 50% (P wheel running, nor was glucose tolerance improved. Exercise...
Brain-Derived Neurotrophic Factor Val66Met Human Polymorphism Impairs the Beneficial Exercise-Induced Neurobiological Changes in Mice

Science.gov (United States)

Ieraci, Alessandro; Madaio, Alessandro I; Mallei, Alessandra; Lee, Francis S; Popoli, Maurizio

2016-01-01

Several studies have shown that exercise improves cognitive functions and emotional behaviors. Positive effects of exercise have been associated with enhanced brain plasticity, adult hippocampal neurogenesis, and increased levels of brain-derived neurotrophic factor (BDNF). However, a substantial variability of individual response to exercise has been described, which may be accounted for by individual genetic variants. Here, we have assessed whether and how the common human BDNF Val66Met polymorphism influences the neurobiological effects modulated by exercise in BDNF Val66Met knock-in male mice. Wild-type (BDNFVal/Val) and homozygous BDNF Val66Met (BDNFMet/Met) male mice were housed in cages equipped with or without running wheels for 4 weeks. Changes in behavioral phenotype, hippocampal adult neurogenesis, and gene expression were evaluated in exercised and sedentary control mice. We found that exercise reduced the latency to feed in the novelty suppressed feeding and the immobility time in the forced swimming test in BDNFVal/Val but not in BDNFMet/Met mice. Hippocampal neurogenesis was reduced in BDNFMet/Met mice compared with BDNFVal/Val mice. BDNFMet/Met mice had lower basal BDNF protein levels in the hippocampus, which was not recovered following exercise. Moreover, exercise-induced expression of total BDNF, BDNF splice variants 1, 2, 4, 6 and fibronectin type III domain-containing protein 5 (FNDC5) mRNA levels were absent or reduced in the dentate gyrus of BDNFMet/Met mice. Exercise failed to enhance PGC-1α and FNDC5 mRNA levels in the BDNFMet/Met muscle. Overall these results indicate that, in adult male mice, the BDNF Val66Met polymorphism impairs the beneficial behavioral and neuroplasticity effects induced by physical exercise. PMID:27388329
A comparison of myogenic motor evoked responses to electrical and magnetic transcranial stimulation during nitrous oxide/opioid anesthesia

NARCIS (Netherlands)

Ubags, L. H.; Kalkman, C. J.; Been, H. D.; Koelman, J. H.; Ongerboer de Visser, B. W.

1999-01-01

Transcranial motor evoked potentials (tc-MEPs) are used to monitor spinal cord integrity intraoperatively. We compared myogenic motor evoked responses with electrical and magnetic transcranial stimuli during nitrous oxide/opioid anesthesia. In 11 patients undergoing spinal surgery, anesthesia was
The Angiotensin Converting Enzyme Insertion/Deletion Polymorphism Modifies Exercise-Induced Muscle Metabolism.

Directory of Open Access Journals (Sweden)

David Vaughan

Full Text Available A silencer region (I-allele within intron 16 of the gene for the regulator of vascular perfusion, angiotensin-converting enzyme (ACE, is implicated in phenotypic variation of aerobic fitness and the development of type II diabetes. We hypothesised that the reportedly lower aerobic performance in non-carriers compared to carriers of the ACE I-allele, i.e. ACE-DD vs. ACE-ID/ACE-II genotype, is associated with alterations in activity-induced glucose metabolism and capillarisation in exercise muscle.Fifty-three, not-specifically trained Caucasian men carried out a one-legged bout of cycling exercise to exhaustion and/or participated in a marathon, the aim being to identify and validate genotype effects on exercise metabolism. Respiratory exchange ratio (RER, serum glucose and lipid concentration, glycogen, and metabolite content in vastus lateralis muscle based on ultra-performance lipid chromatography-mass spectrometry (UPLC-MS, were assessed before and after the cycling exercise in thirty-three participants. Serum metabolites were measured in forty subjects that completed the marathon. Genotype effects were assessed post-hoc.Cycling exercise reduced muscle glycogen concentration and this tended to be affected by the ACE I-allele (p = 0.09. The ACE-DD genotype showed a lower maximal RER and a selective increase in serum glucose concentration after exercise compared to ACE-ID and ACE-II genotypes (+24% vs. +2% and -3%, respectively. Major metabolites of mitochondrial metabolism (i.e. phosphoenol pyruvate, nicotinamide adenine dinucleotide phosphate, L-Aspartic acid, glutathione were selectively affected in vastus lateralis muscle by exercise in the ACE-DD genotype. Capillary-to-fibre ratio was 24%-lower in the ACE-DD genotype. Individuals with the ACE-DD genotype demonstrated an abnormal increase in serum glucose to 7.7 mM after the marathon.The observations imply a genetically modulated role for ACE in control of glucose import and oxidation in
Expression of developmental myosin and morphological characteristics in adult rat skeletal muscle following exercise-induced injury.

Science.gov (United States)

Smith, H K; Plyley, M J; Rodgers, C D; McKee, N H

1999-07-01

The extent and stability of the expression of developmental isoforms of myosin heavy chain (MHCd), and their association with cellular morphology, were determined in adult rat skeletal muscle fibres following injury induced by eccentrically-biased exercise. Adult female Wistar rats [274 (10) g] were either assigned as non-exercised controls or subjected to 30 min of treadmill exercise (grade, -16 degrees; speed, 15 m x min(-1)), and then sacrificed following 1, 2, 4, 7, or 12 days of recovery (n = 5-6 per group). Histologically and immunohistologically stained serial, transverse cryosections of the soleus (S), vastus intermedius (VI), and tibialis anterior (TA) muscles were examined using light microscopy and digital imaging. Fibres staining positively for MHCd (MHCd+) were seldom detected in the TA. In the VI and S, higher proportions of MHCd+ fibres (0.8% and 2.5%, respectively) were observed in rats at 4 and 7 days post-exercise, in comparison to all other groups combined (0.2%, 1.2%; P < or = 0.01). In S, MHCd+ fibres were observed less frequently by 12 days (0.7%) than at 7 days (2.6%) following exercise. The majority (85.1%) of the MHCd+ fibres had morphological characteristics indicative of either damage, degeneration, repair or regeneration. Most of the MHCd+ fibres also expressed adult slow, and/or fast myosin heavy chain. Quantitatively, the MHCd+ fibres were smaller (< 2500 microm2) and more angular than fibres not expressing MHCd. Thus, there was a transient increase in a small, but distinct population of MHCd+ fibres following unaccustomed, functional exercise in adult rat S and VI muscles. The observed close coupling of MHCd expression with morphological changes within muscle fibres suggests that these characteristics have a common, initial exercise-induced injury-related stimulus.
Exercise-induced changes in left ventricular global longitudinal strain in asymptomatic severe aortic stenosis.

Science.gov (United States)

Lech, Agnieszka K; Dobrowolski, Piotr P; Klisiewicz, Anna; Hoffman, Piotr

2017-01-01

The management of patients with asymptomatic severe aortic stenosis (ASAS) is still under discussion. Therefore, it is advisable to search for the parameters of early damage to left ventricular (LV) function. The aim of the study was to assess exercise-induced changes in LV global longitudinal strain (GLS) in ASAS. The ASAS group consisted of 50 patients (26 women and 24 men, aged 38.4 ± 18.1 years) meeting the echocardiographic criteria of severe aortic stenosis (AVA 4 m/s, mean aortic gradient > 40 mm Hg), with normal LV ejection fraction (LVEF ≥ 55%) and sinus rhythm on electrocardiogram, and without significant concomitant valvular heart diseases. The control group consisted of 21 people matched for age and sex. Echocardiographic examinations and echocardiographic stress tests with the assessment of GLS using the speckle tracking imaging were performed. The ASAS group was characterised by statistically significantly higher LV mass index (LVMI) and higher LVEF. GLS values at rest in both groups were within normal limits but were significantly higher in the control group (-18.9 ± 2.4% vs. -20.7 ± 1.7%, p = 0.006). An increase in GLS at peak exercise in both groups was observed, lower in the ASAS group (the difference was not statistically significant: -0.8 ± 3.0% vs. -2.2 ± 3.1%, p = 0.086). Changes in GLS during exercise (ΔGLS) did not correlate with the parameters of the severity of aortic stenosis. In the multivariate model, LVMI proved to be a factor associated with GLS at rest and during exercise. In patients with ASAS, GLS is a non-invasive marker of an early stage of LV myocardial damage associated with myocardial hypertrophy. An increase in GLS during exercise in the ASAS group, smaller than in the control group, indicates a preserved functional reserve of the LV myocardium but smaller than in healthy individuals. The assessment of the clinical usefulness of exercise-induced changes in GLS requires further research.
Effects of carbohydrate supplements on exercise-induced menstrual dysfunction and ovarian subcellular structural changes in rats

Directory of Open Access Journals (Sweden)

Can Zhao

2014-09-01

Conclusion: Female adult rats with 9-week continuous exercise can cause menstrual dysregulation as a model for EAMD. Post-EAMD intervention with glucose and oligosaccharide intake can normalize the menstrual cycle, restore the follicular subcellular structure, and reverse the exercise-induced reduction of ovary sex hormones. It suggests a positive feedback of hypothalamus–pituitary–ovary axis might be involved in the molecular mechanisms of energy intake in treating EAMD.
Exhaustive Exercise-induced Oxidative Stress Alteration of Erythrocyte Oxygen Release Capacity.

Science.gov (United States)

Xiong, Yanlian; Xiong, Yanlei; Wang, Yueming; Zhao, Yajin; Li, Yaojin; Ren, Yang; Wang, Ruofeng; Zhao, Mingzi; Hao, Yitong; Liu, Haibei; Wang, Xiang

2018-05-24

The aim of the present study is to explore the effect of exhaustive running exercise (ERE) in the oxygen release capacity of rat erythrocytes. Rats were divided into sedentary control (C), moderate running exercise (MRE) and exhaustive running exercise groups. The thermodynamics and kinetics properties of the erythrocyte oxygen release process of different groups were tested. We also determined the degree of band-3 oxidative and phosphorylation, anion transport activity and carbonic anhydrase isoform II(CAII) activity. Biochemical studies suggested that exhaustive running significantly increased oxidative injury parameters in TBARS and methaemoglobin levels. Furthermore, exhaustive running significantly decreased anion transport activity and carbonic anhydrase isoform II(CAII) activity. Thermodynamic analysis indicated that erythrocytes oxygen release ability also significantly increased due to elevated 2,3-DPG level after exhaustive running. Kinetic analysis indicated that exhaustive running resulted in significantly decreased T50 value. We presented evidence that exhaustive running remarkably impacted thermodynamics and kinetics properties of RBCs oxygen release. In addition, changes in 2,3-DPG levels and band-3 oxidation and phosphorylation could be the driving force for exhaustive running induced alterations in erythrocytes oxygen release thermodynamics and kinetics properties.
Exercise-induced amenorrhea.

Science.gov (United States)

Olson, B R

1989-02-01

Strenuous exercise may cause menstrual abnormalities, including amenorrhea. The hypoestrogenemia that accompanies amenorrhea has been associated with a low bone mineral content and an increased incidence of stress fractures. With the resumption of menses, which usually occurs soon after female athletes decrease the intensity of their training or increase their body weight, bone mineral content increases and the incidence of stress fractures decreases.
Effects of air-pulsed cryotherapy on neuromuscular recovery subsequent to exercise-induced muscle damage.

Science.gov (United States)

Guilhem, Gaël; Hug, François; Couturier, Antoine; Regnault, Stéphanie; Bournat, Laure; Filliard, Jean-Robert; Dorel, Sylvain

2013-08-01

Localized cooling has been proposed as an effective strategy to limit the deleterious effects of exercise-induced muscle damage on neuromuscular function. However, the literature reports conflicting results. This randomized controlled trial aimed to determine the effects of a new treatment, localized air-pulsed cryotherapy (-30°C), on the recovery time-course of neuromuscular function following a strenuous eccentric exercise. Controlled laboratory study. A total of 24 participants were included in either a control group (CONT) or a cryotherapy group (CRYO). Immediately after 3 sets of 20 maximal isokinetic eccentric contractions of elbow flexors, and then 1, 2, and 3 days after exercise, the CRYO group received a cryotherapy treatment (3 × 4 minutes at -30°C separated by 1 minute). The day before and 1, 2, 3, 7, and 14 days after exercise, several parameters were quantified: maximal isometric torque and its associated maximal electromyographic activity recorded by a 64-channel electrode, delayed-onset muscle soreness (DOMS), biceps brachii transverse relaxation time (T2) measured using magnetic resonance imaging, creatine kinase activity, interleukin-6, and C-reactive protein. Maximal isometric torque decreased similarly for the CONT (-33% ± 4%) and CRYO groups (-31% ± 6%). No intergroup differences were found for DOMS, electromyographic activity, creatine kinase activity, and T2 level averaged across the whole biceps brachii. C-reactive protein significantly increased for CONT (+93% at 72 hours, P cryotherapy delayed the significant increase of T2 and the decrease of electromyographic activity level for CRYO compared with CONT (between day 1 and day 3) in the medio-distal part of the biceps brachii. Although some indicators of muscle damage after severe eccentric exercise were delayed (ie, local formation of edema and decrease of muscle activity) by repeated air-pulsed cryotherapy, we provide evidence that this cooling procedure failed to improve long
Recovery From Exercise-Induced Muscle Damage: Cold-Water Immersion Versus Whole-Body Cryotherapy.

Science.gov (United States)

Abaïdia, Abd-Elbasset; Lamblin, Julien; Delecroix, Barthélémy; Leduc, Cédric; McCall, Alan; Nédélec, Mathieu; Dawson, Brian; Baquet, Georges; Dupont, Grégory

2017-03-01

To compare the effects of cold-water immersion (CWI) and whole-body cryotherapy (WBC) on recovery kinetics after exercise-induced muscle damage. Ten physically active men performed single-leg hamstring eccentric exercise comprising 5 sets of 15 repetitions. Immediately postexercise, subjects were exposed in a randomized crossover design to CWI (10 min at 10°C) or WBC (3 min at -110°C) recovery. Creatine kinase concentrations, knee-flexor eccentric (60°/s) and posterior lower-limb isometric (60°) strength, single-leg and 2-leg countermovement jumps, muscle soreness, and perception of recovery were measured. The tests were performed before and immediately, 24, 48, and 72 h after exercise. Results showed a very likely moderate effect in favor of CWI for single-leg (effect size [ES] = 0.63; 90% confidence interval [CI] = -0.13 to 1.38) and 2-leg countermovement jump (ES = 0.68; 90% CI = -0.08 to 1.43) 72 h after exercise. Soreness was moderately lower 48 h after exercise after CWI (ES = -0.68; 90% CI = -1.44 to 0.07). Perception of recovery was moderately enhanced 24 h after exercise for CWI (ES = -0.62; 90% CI = -1.38 to 0.13). Trivial and small effects of condition were found for the other outcomes. CWI was more effective than WBC in accelerating recovery kinetics for countermovement-jump performance at 72 h postexercise. CWI also demonstrated lower soreness and higher perceived recovery levels across 24-48 h postexercise.
Exercise and exercise training-induced increase in autophagy markers in human skeletal muscle

DEFF Research Database (Denmark)

Brandt, Nina; Gunnarsson, Thomas Gunnar Petursson; Bangsbo, Jens

2018-01-01

Moderately trained male subjects (mean age 25 years; range 19-33 years) completed an 8-week exercise training intervention consisting of continuous moderate cycling at 157 ± 20 W for 60 min (MOD; n = 6) or continuous moderate cycling (157 ± 20 W) interspersed by 30-sec sprints (473 ± 79 W) every 10...... muscle AMPKThr172 and ULKSer317 phosphorylation was elevated immediately after exercise, whereas mTORSer2448 and ULKSer757 phosphorylation was unchanged. Two hours after exercise LC3I, LC3II and BNIP3 protein content was overall higher than before exercise with no change in p62 protein. In MOD, Beclin1...... protein content was higher immediately and 2 h after exercise than before exercise, while there were no differences within SPRINT. Oxphos complex I, LC3I, BNIP3 and Parkin protein content was higher after the training intervention than before in both groups, while there was no difference in LC3II and p62...

Quality of Life after Diet or Exercise-Induced Weight Loss in Overweight to Obese Postmenopausal Women: The SHAPE-2 Randomised Controlled Trial.

Directory of Open Access Journals (Sweden)

Willemijn A M van Gemert

Full Text Available This study investigates the effect of a modest weight loss either by a calorie restricted diet or mainly by increased physical exercise on health related quality of life (HRQoL in overweight-to-obese and inactive postmenopausal women. We hypothesize that HRQoL improves with weight loss, and that exercise-induced weight loss is more effective for this than diet-induced weight loss.The SHAPE-2 trial was primarily designed to evaluate any additional effect of weight loss by exercise compared with a comparable amount of weight loss by diet on biomarkers relevant for breast cancer risk. In the present analysis we focus on HRQoL. We randomly assigned 243 eligible women to a diet (n = 97, exercise (n = 98, or control group (n = 48. Both interventions aimed for 5-6 kg weight loss. HRQoL was measured at baseline and after 16 weeks by the SF-36 questionnaire.Data of 214 women were available for analysis. Weight loss was 4.9 kg (6.1% and 5.5 kg (6.9% with diet and exercise, respectively. Scores of the SF-36 domain 'health change' increased significantly by 8.8 points (95% CI 1.6;16.1 with diet, and by 20.5 points (95% CI 13.2;27.7 with exercise when compared with control. Direct comparison of diet and exercise showed a statistically significantly stronger improvement with exercise. Both intervention groups showed a tendency towards improvements in most other domains, which were more pronounced in the exercise group, but not statistically different from control or each other.In a randomized trial in overweight-to-obese and inactive postmenopausal women a comparable 6%-7% weight loss was achieved by diet-only or mainly by exercise and showed improvements in physical and mental HRQoL domains, but results were not statistically significant in either the diet or exercise group. However, a modest weight loss does lead to a positive change in self-perceived health status. This effect was significantly larger with exercise-induced weight loss than with comparable
Quality of Life after Diet or Exercise-Induced Weight Loss in Overweight to Obese Postmenopausal Women: The SHAPE-2 Randomised Controlled Trial.

Science.gov (United States)

van Gemert, Willemijn A M; van der Palen, Job; Monninkhof, Evelyn M; Rozeboom, Anouk; Peters, Roelof; Wittink, Harriet; Schuit, Albertine J; Peeters, Petra H

2015-01-01

This study investigates the effect of a modest weight loss either by a calorie restricted diet or mainly by increased physical exercise on health related quality of life (HRQoL) in overweight-to-obese and inactive postmenopausal women. We hypothesize that HRQoL improves with weight loss, and that exercise-induced weight loss is more effective for this than diet-induced weight loss. The SHAPE-2 trial was primarily designed to evaluate any additional effect of weight loss by exercise compared with a comparable amount of weight loss by diet on biomarkers relevant for breast cancer risk. In the present analysis we focus on HRQoL. We randomly assigned 243 eligible women to a diet (n = 97), exercise (n = 98), or control group (n = 48). Both interventions aimed for 5-6 kg weight loss. HRQoL was measured at baseline and after 16 weeks by the SF-36 questionnaire. Data of 214 women were available for analysis. Weight loss was 4.9 kg (6.1%) and 5.5 kg (6.9%) with diet and exercise, respectively. Scores of the SF-36 domain 'health change' increased significantly by 8.8 points (95% CI 1.6;16.1) with diet, and by 20.5 points (95% CI 13.2;27.7) with exercise when compared with control. Direct comparison of diet and exercise showed a statistically significantly stronger improvement with exercise. Both intervention groups showed a tendency towards improvements in most other domains, which were more pronounced in the exercise group, but not statistically different from control or each other. In a randomized trial in overweight-to-obese and inactive postmenopausal women a comparable 6%-7% weight loss was achieved by diet-only or mainly by exercise and showed improvements in physical and mental HRQoL domains, but results were not statistically significant in either the diet or exercise group. However, a modest weight loss does lead to a positive change in self-perceived health status. This effect was significantly larger with exercise-induced weight loss than with comparable diet-induced
Chronic Caloric Restriction and Exercise Improve Metabolic Conditions of Dietary-Induced Obese Mice in Autophagy Correlated Manner without Involving AMPK

Directory of Open Access Journals (Sweden)

Mingxia Cui

2013-01-01

Full Text Available Aim. To investigate the role of AMPK activation and autophagy in mediating the beneficial effects of exercise and caloric restriction in obesity. Methods. Dietary-induced obesity mice were made and divided into 5 groups; one additional group of normal mice serves as control. Mice in each group received different combinations of interventions including low fat diet, caloric restriction, and exercise. Then their metabolic conditions were assessed by measuring serum glucose and insulin, serum lipids, and liver function. AMPK phosphorylation and autophagy activity were detected by western blotting. Results. Obese mice models were successfully induced by high fat diet. Caloric restriction consistently improved the metabolic conditions of the obese mice, and the effects are more prominent than the mice that received only exercise. Also, caloric restriction, exercise, and low fat diet showed a synergistic effect in the improvement of metabolic conditions. Western blotting results showed that this improvement was not related with the activation of AMPK in liver, skeletal muscle, or heart but correlates well with the autophagy activity. Conclusion. Caloric restriction has more prominent beneficial effects than exercise in dietary-induced obese mice. These effects are correlated with the autophagy activity and may be independent of AMPK activation.
Cognitive Performance Enhancement Induced by Caffeine, Carbohydrate and Guarana Mouth Rinsing during Submaximal Exercise.

Science.gov (United States)

Pomportes, Laura; Brisswalter, Jeanick; Casini, Laurence; Hays, Arnaud; Davranche, Karen

2017-06-09

The aim of this study was to investigate the influence of serial mouth rinsing (MR) with nutritional supplements on cognitive performance (i.e., cognitive control and time perception) during a 40-min submaximal exercise. Twenty-four participants completed 4 counterbalanced experimental sessions, during which they performed MR with either placebo (PL), carbohydrate (CHO: 1.6 g/25 mL), guarana complex (GUAc: 0.4 g/25 mL) or caffeine (CAF: 67 mg/25 mL) before and twice during exercise. The present study provided some important new insights regarding the specific changes in cognitive performance induced by nutritional supplements. The main results were: (1) CHO, CAF and GUA MR likely led participants to improve temporal performance; (2) CAF MR likely improved cognitive control; and (3) CHO MR led to a likely decrease in subjective perception of effort at the end of the exercise compared to PL, GUA and CAF. Moreover, results have shown that performing 40-min submaximal exercise enhances information processing in terms of both speed and accuracy, improves temporal performance and does not alter cognitive control. The present study opens up new perspectives regarding the use of MR to optimize cognitive performance during physical exercise.
Development and validation of a questionnaire to measure the severity of functional limitations and reduction of sports ability in German-speaking patients with exercise-induced leg pain.

Science.gov (United States)

Nauck, Tanja; Lohrer, Heinz; Padhiar, Nat; King, John B

2015-01-01

Currently, there is no generally agreed measure available to quantify a subject's perceived severity of exercise-induced leg pain symptoms. The aim of this study was to develop and validate a questionnaire that measures the severity of symptoms that impact on function and sports ability in patients with exercise-induced leg pain. The exercise-induced leg pain questionnaire for German-speaking patients (EILP-G) was developed in five steps: (1) initial item generation, (2) item reduction, (3) pretesting, (4) expert meeting and (5) validation. The resulting EILP-G was tested for reliability, validity and internal consistency in 20 patients with exercise-induced leg pain, 20 asymptomatic track and field athletes serving as a population at risk and 33 asymptomatic sport students. The patient group scored the EILP-G questionnaire significantly lower than both control groups (each psports ability in patients with exercise-induced leg pain. It can be recommended as a robust tool for measuring the subjectively perceived severity in German-speaking patients with exercise-induced leg pain. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
THE EFFECT OF AN INHALED CORTICOSTEROID (BUDESONIDE) ON EXERCISE-INDUCED ASTHMA IN CHILDREN

NARCIS (Netherlands)

WAALKENS, JH; VANESSENZANDVLIET, EEM; GERRITSEN, J; DUIVERMAN, EJ; KERREBIJN, KF; KNOL, K

The effect of long-term treatment with inhaled corticosteroid on exercise-induced asthma (EIA) was studied in 55 children, aged 7-18 yrs (mean 12 yrs). We also compared the time course of stabilization of EIA to that of other indicators of airway responsiveness, such as peak expiratory flow (PEF)
Large cell/anaplastic medulloblastoma with myogenic, melanotic and neuronal differentiation: A case report of a rare tumor

Directory of Open Access Journals (Sweden)

Amany A. Fathaddin

2014-01-01

Full Text Available Medulloblastoma is an embryonal neuroepithelial tumor of the cerebellum and is the most common malignant central nervous system tumor in children. Different histological variants and patterns have been described. The classic variant represents the majority of cases. This report describes a rare case of large cell/anaplastic medulloblastoma with myogenic, melanotic and neuronal differentiation arising in the cerebellum of a 3-year-old boy who presented with headache and vomiting. Magnetic resonance imaging demonstrated a heterogeneously enhanced lesion in the fourth ventricle. Surgical resection of the tumor was accomplished, but a residual tumor was left behind because of the involvement of the brainstem. Postoperatively, the patient received chemotherapy and radiotherapy. Currently, 20 months after treatment, the patient has survived without further progression. Pathological examination revealed a high grade primitive neuronal tumor with foci of myogenic features, melanin containing epithelial elements and ganglion-like cells, which were confirmed by immunohistochemistry.
Sex and Exercise Interact to Alter the Expression of Anabolic Androgenic Steroid-Induced Anxiety-Like Behaviors in the Mouse

Science.gov (United States)

Onakomaiya, Marie M.; Porter, Donna M.; Oberlander, Joseph G.; Henderson, Leslie P.

2014-01-01

Anabolic androgenic steroids (AAS) are taken by both sexes to enhance athletic performance and body image, nearly always in conjunction with an exercise regime. Although taken to improve physical attributes, chronic AAS use can promote negative behavior, including anxiety. Few studies have directly compared the impact of AAS use in males versus females or assessed the interaction of exercise and AAS. We show that AAS increase anxiety-like behaviors in female but not male mice and that voluntary exercise accentuates these sex-specific differences. We also show that levels of the anxiogenic peptide corticotrophin releasing factor (CRF) are significantly greater in males, but that AAS selectively increase CRF levels in females, thus abrogating this sex-specific difference. Exercise did not ameliorate AAS-induced anxiety or alter CRF levels in females. Exercise was anxiolytic in males, but this behavioral outcome did not correlate with CRF levels. Brain-derived neurotrophic factor (BDNF) has also been implicated in the expression of anxiety. As with CRF, levels of hippocampal BDNF mRNA were significantly greater in males than females. AAS and exercise were without effect on BDNF mRNA in females. In males, anxiolytic effects of exercise correlated with increased BDNF mRNA, however AAS-induced changes in BDNF mRNA and anxiety did not. In sum, we find that AAS elicit sex-specific differences in anxiety and that voluntary exercise accentuates these differences. In addition, our data suggest that these behavioral outcomes may reflect convergent actions of AAS and exercise on a sexually differentiated CRF signaling system within the extended amygdala. PMID:24768711
Can palpation-induced muscle pain pattern contribute to the differential diagnosis among temporomandibular disorders, primary headaches phenotypes and possible bruxism?

Science.gov (United States)

Costa, Yuri-Martins; Porporatti, André-Luís; Calderon, Patrícia-dos-Santos; Conti, Paulo-César-Rodrigues; Bonjardim, Leonardo-Rigoldi

2016-01-01

The evaluation of possible differences in the distribution or characteristics of palpation-induced pain in the masticatory muscles could be valuable in terms of diagnostic assessment. The aim of this study was to evaluate the impact of different combinations of anterior temporalis (AT) and masseter palpation-induced pain in the diagnostic of temporomandibular disorder (TMD), primary headaches and bruxism. A total of 1200 dental records of orofacial pain adult patients were analyzed. The outcomes were dichotomously classified (presence/absence) as following: a) AT and/or masseter palpation-induced pain; b) myogenous TMD; c) temporomandibular joint (TMJ) arthralgia (arthrogenous TMD); d) migraine; e) tension-type headache (TTH); f) self-reported bruxism. Binomial logistic regression model (α = 5%) was applied to the data considering the palpation-induced muscle pain as the dependent variable. Mean age (SD) were 35.7 years (13.4) for 635 included dental records (83% females). Myogenous and arthrogenous TMD, migraine, TTH and bruxism were mainly associated with, respectively, masseter palpation-induced pain (pbruxism.
Decorin expression in quiescent myogenic cells

International Nuclear Information System (INIS)

Nishimura, Takanori; Nozu, Kenjiro; Kishioka, Yasuhiro; Wakamatsu, Jun-ichi; Hattori, Akihito

2008-01-01

Satellite cells are quiescent muscle stem cells that promote postnatal muscle growth and repair. When satellite cells are activated by myotrauma, they proliferate, migrate, differentiate, and ultimately fuse to existing myofibers. The remainder of these cells do not differentiate, but instead return to quiescence and remain in a quiescent state until activation begins the process again. This ability to maintain their own population is important for skeletal muscle to maintain the capability to repair during postnatal life. However, the mechanisms by which satellite cells return to quiescence and maintain the quiescent state are still unclear. Here, we demonstrated that decorin mRNA expression was high in cell cultures containing a higher ratio of quiescent satellite cells when satellite cells were stimulated with various concentrations of hepatocyte growth factor. This result suggests that quiescent satellite cells express decorin at a high level compared to activated satellite cells. Furthermore, we examined the expression of decorin in reserve cells, which were undifferentiated myoblasts remaining after induction of differentiation by serum-deprivation. Decorin mRNA levels in reserve cells were higher than those in differentiated myotubes and growing myoblasts. These results suggest that decorin participates in the quiescence of myogenic cells
Acute post-exercise change in blood pressure and exercise training response in patients with coronary artery disease

Directory of Open Access Journals (Sweden)

Antti M Kiviniemi

2015-01-01

Full Text Available We tested the hypothesis that acute post-exercise change in blood pressure (BP may predict exercise training responses in BP in patients with coronary artery disease (CAD. Patients with CAD (n=116, age 62±5 years, 85 men underwent BP assessments at rest and during 10-min recovery following a symptom-limited exercise test before and after the 6-month training intervention (one strength and 3-4 aerobic moderate-intensity exercises weekly. Post-exercise change in systolic BP (SBP was calculated by subtracting resting SBP from lowest post-exercise SBP. The training-induced change in resting SBP was -2±13 mmHg (p=0.064, ranging from -42 to 35 mmHg. Larger post-exercise decrease in SBP and baseline resting SBP predicted a larger training-induced decrement in SBP (β=0.46 and β=-0.44, respectively, p<0.001 for both. Acute post-exercise decrease in SBP provided additive value to baseline resting SBP in the prediction of training-induced change in resting SBP (R squared from 0.20 to 0.26, p=0.002. After further adjustments for other potential confounders (sex, age, baseline body mass index, realized training load, post-exercise decrease in SBP still predicted the training response in resting SBP (β=0.26, p=0.015. Acute post-exercise change in SBP was associated with training-induced change in resting SBP in patients with CAD, providing significant predictive information beyond baseline resting SBP.
A multi-component parallel-plate flow chamber system for studying the effect of exercise-induced wall shear stress on endothelial cells.

Science.gov (United States)

Wang, Yan-Xia; Xiang, Cheng; Liu, Bo; Zhu, Yong; Luan, Yong; Liu, Shu-Tian; Qin, Kai-Rong

2016-12-28

In vivo studies have demonstrated that reasonable exercise training can improve endothelial function. To confirm the key role of wall shear stress induced by exercise on endothelial cells, and to understand how wall shear stress affects the structure and the function of endothelial cells, it is crucial to design and fabricate an in vitro multi-component parallel-plate flow chamber system which can closely replicate exercise-induced wall shear stress waveforms in artery. The in vivo wall shear stress waveforms from the common carotid artery of a healthy volunteer in resting and immediately after 30 min acute aerobic cycling exercise were first calculated by measuring the inner diameter and the center-line blood flow velocity with a color Doppler ultrasound. According to the above in vivo wall shear stress waveforms, we designed and fabricated a parallel-plate flow chamber system with appropriate components based on a lumped parameter hemodynamics model. To validate the feasibility of this system, human umbilical vein endothelial cells (HUVECs) line were cultured within the parallel-plate flow chamber under abovementioned two types of wall shear stress waveforms and the intracellular actin microfilaments and nitric oxide (NO) production level were evaluated using fluorescence microscope. Our results show that the trends of resting and exercise-induced wall shear stress waveforms, especially the maximal, minimal and mean wall shear stress as well as oscillatory shear index, generated by the parallel-plate flow chamber system are similar to those acquired from the common carotid artery. In addition, the cellular experiments demonstrate that the actin microfilaments and the production of NO within cells exposed to the two different wall shear stress waveforms exhibit different dynamic behaviors; there are larger numbers of actin microfilaments and higher level NO in cells exposed in exercise-induced wall shear stress condition than resting wall shear stress condition
Exercise-induced muscle damage and the repeated bout effect: evidence for cross transfer.

Science.gov (United States)

Starbuck, Chelsea; Eston, Roger G

2012-03-01

We examined whether a prior bout of eccentric exercise in the elbow flexors provided protection against exercise-induced muscle damage in the contralateral arm. Fifteen males (age 22.7 ± 2.1 years; height 178.6 ± 6.8 cm, mass 75.8 ± 9.3 kg) were randomly assigned to two groups who performed two bouts of 60 eccentric contractions (30°/s) separated by 2 weeks: ipsilateral (n = 7, both bouts performed in the same arm), contralateral (n = 8, one bout performed in each arm). Strength, muscle soreness and resting arm angle (RAA) were measured at baseline and at 1, 24 and 48 h post exercise. Surface electromyography was recorded during both bouts of exercise. The degree of strength loss was attenuated (p < 0.05) in the ipsilateral group after the second bout of eccentric exercise (-22 cf. -3% for bout 1 and 2 at 24 h, respectively). Strength loss following eccentric exercise was also attenuated (p < 0.05) at 24 h in the contralateral group (-30 cf. 13% for bout 1 and 2, respectively). Muscle soreness (≈34 cf 19 mm) and change in RAA (≈5 cf. 3%) were also lower following the second bout of eccentric exercise (p < 0.05), although there was no difference in the overall change in these values between groups. Median frequency (MF) was decreased by 31% between bouts, with no difference between groups. Data support observations that the repeated bout effect transfers to the opposite (untrained) limb. The similar reduction in MF between bouts for the two groups provides evidence for a centrally mediated, neural adaptation.
Perception of Exercise-Induced Bronchoconstriction in College Athletes.

Science.gov (United States)

Burnett, David M; Vardiman, John P; Deckert, Jake A; Ward, Jaimie L; Sharpe, Matthew R

2016-07-01

Exercise-induced bronchoconstriction (EIB) can lead to long-term respiratory illness and even death. EIB prevalence rates are both high and variable in college athletes. Also, prevalence rates may be underestimated due to ineffective screening. The purpose of this study is to investigate the prevalence of EIB and the perceived impact of EIB in college athletes via a self-report questionnaire. A self-report EIB questionnaire was administered to college athletes on 8 different sports teams. Information collected was used to identify athletes who self-reported: (1) a history of EIB and/or asthma, (2) respiratory symptoms during exercise, (3) medication use, and (4) concern about EIB. Results showed that 56 of 196 athletes (28.6%) self-reported a history of EIB or asthma. Over half (52%) reported a history of EIB/asthma or current EIB symptoms. Forty-six of the 140 athletes (32.9%) who did not report a history of EIB or asthma indicated symptoms of EIB during sports, training, or exercise. Fourteen of 56 athletes (25%) self-reporting a history of EIB or asthma did not report the use of a respiratory medication. Nineteen of 196 athletes (9.7%) reported being concerned that EIB was adversely affecting their sports performance. College athletes self-report a high prevalence of EIB or asthma. Although college athletes may not report a history of EIB or asthma, they indicate symptoms of EIB. A majority of athletes reported a history or current symptoms related to EIB or asthma. Many athletes with a history of EIB or asthma are not taking any asthma medication. Last, athletes report concern about EIB adversely affecting their sports performance. More work is needed using a combination of a screening questionnaire and standardized EIB testing to develop a validated tool for accurately screening and diagnosing EIB in college athletes. Copyright © 2016 by Daedalus Enterprises.
Inducible laryngeal obstruction during exercise: moving beyond vocal cords with new insights.

Science.gov (United States)

Olin, James Tod; Clary, Matthew S; Deardorff, Emily H; Johnston, Kristina; Morris, Michael J; Sokoya, Mofiyinfolu; Staudenmayer, Herman; Christopher, Kent L

2015-02-01

Exercise as an important part of life for the health and wellness of children and adults. Inducible laryngeal obstruction (ILO) is a consensus term used to describe a group of disorders previously called vocal cord dysfunction, paradoxical vocal fold motion, and numerous other terms. Exercise-ILO can impair one's ability to exercise, can be confused with asthma, leading to unnecessary prescription of asthma controller and rescue medication, and results in increased healthcare resource utilization including (rarely) emergency care. It is characterized by episodic shortness of breath and noisy breathing that generally occurs at high work rates. The present diagnostic gold standard for all types of ILO is laryngoscopic visualization of inappropriate glottic or supraglottic movement resulting in airway narrowing during a spontaneous event or provocation challenge. A number of different behavioral techniques, including speech therapy, biofeedback, and cognitive-behavioral psychotherapy, may be appropriate to treat individual patients. A consensus nomenclature, which will allow for better characterization of patients, coupled with new diagnostic techniques, may further define the epidemiology and etiology of ILO as well as enable objective evaluation of therapeutic modalities.
Cervical flexion-rotation test and physiological range of motion - A comparative study of patients with myogenic temporomandibular disorder versus healthy subjects.

Science.gov (United States)

Greenbaum, Tzvika; Dvir, Zeevi; Reiter, Shoshana; Winocur, Ephraim

2017-02-01

Temporomandibular Disorders (TMD) refer to several common clinical disorders which involve the masticatory muscles, the temporomandibular joint (TMJ) and the adjacent structures. Although neck signs and symptoms are found with higher prevalence in TMD patients compared to the overall population, whether limitation of cervical mobility is an additional positive finding in this cohort is still an open question. To compare the physiological cervical range of motion (CROM) and the extent of rotation during cervical flexion (flexion-rotation test, FRT) in people with TMD (muscular origin) and healthy control subjects. The range of motion of the neck and FRT was measured in 20 women with myogenic TMD and 20 age matched healthy controls. Women with myogenic TMD had significantly lower FRT scores compared to their matched healthy women. No difference was found between groups in CROM in any of the planes of movement. The FRT was positive (less than 32°) in 90% of the TMD participants versus 5% in the healthy control but the findings were not correlated with TMD severity. The results point out a potential involvement of the upper cervical joints (c1-c2) in women with myogenic TMD. Copyright © 2016 Elsevier Ltd. All rights reserved.
Inhibition of Glutathione Synthesis Induced by Exhaustive Running Exercise via the Decreased Influx Rate of L-Cysteine in Rat Erythrocytes.

Science.gov (United States)

Xiong, Yanlian; Xiong, Yanlei; Zhou, Shuai; Yu, Zhenhai; Zhao, Dongmei; Wang, Zhiqiang; Li, Yuling; Yan, Jingtong; Cai, Yu; Zhang, Wenqian

2016-01-01

The main purpose of this study was to investigate the effect of exhaustive exercise on L-cysteine uptake and its effect on erythrocyte glutathione (GSH) synthesis and metabolism. Rats were divided into three groups: sedentary control (C), exhaustive running exercise (ERE) and moderate running exercise (MRE) (n=12 rats/group). We determined the L-cysteine efflux and influx in vitro in rat erythrocytes and its relationship with GSH synthesis. Total anti-oxidant potential of plasma was measured in terms of the ferric reducing ability of plasma (FRAP) values for each exercise group. In addition, the glucose metabolism enzyme activity of erythrocytes was also measured under in vitro incubation conditions. Biochemical studies confirmed that exhaustive running exercise significantly increased oxidative damage parameters in thiobarbituric acid reactive substances (TBARS) and methemoglobin levels. Pearson correlation analysis suggested that L-cysteine influx was positively correlated with erythrocyte GSH synthesis and FRAP values in both the control and exercise groups. In vitro oxidation incubation significantly decreased the level of glucose metabolism enzyme activity in the control group. We presented evidence of the exhaustive exercise-induced inhibition of GSH synthesis due to a dysfunction in L-cysteine transport. In addition, oxidative stress-induced changes in glucose metabolism were the driving force underlying decreased L-cysteine uptake in the exhaustive exercise group. © 2016 The Author(s) Published by S. Karger AG, Basel.
Do structural changes (eg, collagen/matrix) explain the response to therapeutic exercises in tendinopathy: a systematic review.

Science.gov (United States)

Drew, Benjamin T; Smith, Toby O; Littlewood, Chris; Sturrock, Ben

2014-06-01

Previous reviews have highlighted the benefit of loaded therapeutic exercise in the treatment of tendinopathy. Changes in observable structural outcomes have been suggested as a possible explanation for this response to therapeutic exercise. However, the mechanism for the efficacy of therapeutic exercise remains unclear. To systematically review the relationship between the observable structural change and clinical outcomes following therapeutic exercise. An electronic search of AMED, CiNAHL, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PEDro and SPORTDiscus was undertaken from their inception to June 2012. Any study design that incorporated observable structural outcomes and clinical outcomes when assessing the effect of therapeutic exercise on participants with tendinopathy. Included studies were appraised for risk of bias using the tool developed by the Cochrane Back Review Group. Due to heterogeneity of studies, a qualitative synthesis was undertaken. Twenty articles describing 625 patients were included. Overall, there is a strong evidence to refute any observable structural change as an explanation for the response to therapeutic exercise when treated by eccentric exercise training. Moderate evidence does exist to support the response of heavy-slow resistance training (HSR). The available literature does not support observable structural change as an explanation for the response of therapeutic exercise except for some support from HSR. Future research should focus on indentifying other explanations including neural, biochemical and myogenic changes. Registered with PROSPERO, registration number CRD42011001638. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
High-fat feeding inhibits exercise-induced increase in mitochondrial respiratory flux in skeletal muscle

DEFF Research Database (Denmark)

Skovbro, Mette; Boushel, Robert Christopher; Hansen, Christina Neigaard

2011-01-01

) and intramyocellular triacylglycerol content did not change with the intervention in either group. Indexes of mitochondrial density were similar across the groups and intervention. Mitochondrial respiratory rates, measured in permeabilized muscle fibers, showed a 31 ± 11 and 26 ± 9% exercise-induced increase (P
Differential expression of myogenic regulatory genes and Msx-1 during dedifferentiation and redifferentiation of regenerating amphibian limbs.

Science.gov (United States)

Simon, H G; Nelson, C; Goff, D; Laufer, E; Morgan, B A; Tabin, C

1995-01-01

An amputated limb of an adult urodele amphibian is capable of undergoing regeneration. The new structures form from an undifferentiated mass of cells called the regenerative blastema. The cells of the blastema are believed to derive from differentiated tissues of the adult limb. However, the exact source of these cells and the process by which they undergo dedifferentiation are poorly understood. In order to elucidate the molecular and cellular basis for dedifferentiation we isolated a number of genes which are potential regulators of the process. These include Msx-1, which is believed to support the undifferentiated and proliferative state of cells in the embryonic limb bud; and two members of the myogenic regulatory gene family, MRF-4 and Myf-5, which are expressed in differentiated muscle and regulate muscle-specific gene activity. As anticipated, we find that Msx-1 is strongly up-regulated during the initiation of regeneration. It remains expressed throughout regeneration but is not found in the fully regenerated limb. The myogenic gene MRF-4 has the reverse expression pattern. It is expressed in adult limb muscle, is rapidly shut off in early regenerative blastemas, and is only reexpressed at the completion of regeneration. These kinetics are paralleled by those of a muscle-specific Myosin gene. In contrast Myf-5, a second member of the myogenic gene family, continues to be expressed throughout the regenerative process. Thus, MRF-4 and Myf-5 are likely to play distinct roles during regeneration. MRF-4 may directly regulate muscle phenotype and as such its repression may be a key event in dedifferentiation.(ABSTRACT TRUNCATED AT 250 WORDS)

Some links on this page may take you to non-federal websites. Their policies may differ from this site.