Quantitative analysis of lentiviral transgene expression in mice over seven generations.

Science.gov (United States)

Wang, Yong; Song, Yong-tao; Liu, Qin; Liu, Cang'e; Wang, Lu-lu; Liu, Yu; Zhou, Xiao-yang; Wu, Jun; Wei, Hong

2010-10-01

Lentiviral transgenesis is now recognized as an extremely efficient and cost-effective method to produce transgenic animals. Transgenes delivered by lentiviral vectors exhibited inheritable expression in many species including those which are refractory to genetic modification such as non-human primates. However, epigenetic modification was frequently observed in lentiviral integrants, and transgene expression found to be inversely correlated with methylation density. Recent data showed that about one-third lentiviral integrants exhibited hypermethylation and low expression, but did not demonstrate whether those integrants with high expression could remain constant expression and hypomethylated during long term germline transmission. In this study, using lentiviral eGFP transgenic mice as the experimental animals, lentiviral eGFP expression levels and its integrant numbers in genome were quantitatively analyzed by fluorescent quantitative polymerase-chain reaction (FQ-PCR), using the house-keeping gene ribosomal protein S18 (Rps18) and the single copy gene fatty acid binding protein of the intestine (Fabpi) as the internal controls respectively. The methylation densities of the integrants were quantitatively analyzed by bisulfite sequencing. We found that the lentiviral integrants with high expression exhibited a relative constant expression level per integrant over at least seven generations. Besides, the individuals containing these integrants exhibited eGFP expression levels which were positively and almost linearly correlated with the integrant numbers in their genomes, suggesting that no remarkable position effect on transgene expression of the integrants analyzed was observed. In addition, over seven generations the methylation density of these integrants did not increase, but rather decreased remarkably, indicating that these high expressing integrants were not subjected to de novo methylation during at least seven generations of germline transmission. Taken

Administration of red ginseng ameliorates memory decline in aged mice.

Science.gov (United States)

Lee, Yeonju; Oh, Seikwan

2015-07-01

It has been known that ginseng can be applied as a potential nutraceutical for memory impairment; however, experiments with animals of old age are few. To determine the memory enhancing effect of red ginseng, C57BL/6 mice (21 mo old) were given experimental diet pellets containing 0.12% red ginseng extract (approximately 200 mg/kg/d) for 3 mo. Young and old mice (4 mo and 21 mo old, respectively) were used as the control group. The effect of red ginseng, which ameliorated memory impairment in aged mice, was quantified using Y-maze test, novel objective test, and Morris water maze. Red ginseng ameliorated age-related declines in learning and memory in older mice. In addition, red ginseng's effect on the induction of inducible nitric oxide synthase and proinflammatory cytokines was investigated in the hippocampus of aged mice. Red ginseng treatment suppressed the production of age-processed inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor-α, and interleukin-1β expressions. Moreover, it was observed that red ginseng had an antioxidative effect on aged mice. The suppressed glutathione level in aged mice was restored with red ginseng treatment. The antioxidative-related enzymes Nrf2 and HO-1 were increased with red ginseng treatment. The results revealed that when red ginseng is administered over long periods, age-related decline of learning and memory is ameliorated through anti-inflammatory activity.

CRF receptor antagonist astressin-B reverses and prevents alopecia in CRF over-expressing mice.

Directory of Open Access Journals (Sweden)

Lixin Wang

2011-02-01

Full Text Available Corticotropin-releasing factor (CRF signaling pathways are involved in the stress response, and there is growing evidence supporting hair growth inhibition of murine hair follicle in vivo upon stress exposure. We investigated whether the blockade of CRF receptors influences the development of hair loss in CRF over-expressing (OE-mice that display phenotypes of Cushing's syndrome and chronic stress, including alopecia. The non-selective CRF receptors antagonist, astressin-B (5 µg/mouse injected peripherally once a day for 5 days in 4-9 months old CRF-OE alopecic mice induced pigmentation and hair re-growth that was largely retained for over 4 months. In young CRF-OE mice, astressin-B prevented the development of alopecia that occurred in saline-treated mice. Histological examination indicated that alopecic CRF-OE mice had hair follicle atrophy and that astressin-B revived the hair follicle from the telogen to anagen phase. However, astressin-B did not show any effect on the elevated plasma corticosterone levels and the increased weights of adrenal glands and visceral fat in CRF-OE mice. The selective CRF₂ receptor antagonist, astressin₂-B had moderate effect on pigmentation, but not on hair re-growth. The commercial drug for alopecia, minoxidil only showed partial effect on hair re-growth. These data support the existence of a key molecular switching mechanism triggered by blocking peripheral CRF receptors with an antagonist to reset hair growth in a mouse model of alopecia associated with chronic stress.

Erythropoietin over-expression protects against diet-induced obesity in mice through increased fat oxidation in muscles.

Directory of Open Access Journals (Sweden)

Pernille Hojman

Full Text Available Erythropoietin can be over-expressed in skeletal muscles by gene electrotransfer, resulting in 100-fold increase in serum EPO and significant increases in haemoglobin levels. Earlier studies have suggested that EPO improves several metabolic parameters when administered to chronically ill kidney patients. Thus we applied the EPO over-expression model to investigate the metabolic effect of EPO in vivo.At 12 weeks, EPO expression resulted in a 23% weight reduction (P<0.01 in EPO transfected obese mice; thus the mice weighed 21.9+/-0.8 g (control, normal diet, 21.9+/-1.4 g (EPO, normal diet, 35.3+/-3.3 g (control, high-fat diet and 28.8+/-2.6 g (EPO, high-fat diet. Correspondingly, DXA scanning revealed that this was due to a 28% reduction in adipose tissue mass.The decrease in adipose tissue mass was accompanied by a complete normalisation of fasting insulin levels and glucose tolerance in the high-fat fed mice. EPO expression also induced a 14% increase in muscle volume and a 25% increase in vascularisation of the EPO transfected muscle. Muscle force and stamina were not affected by EPO expression. PCR array analysis revealed that genes involved in lipid metabolism, thermogenesis and inflammation were increased in muscles in response to EPO expression, while genes involved in glucose metabolism were down-regulated. In addition, muscular fat oxidation was increased 1.8-fold in both the EPO transfected and contralateral muscles.In conclusion, we have shown that EPO when expressed in supra-physiological levels has substantial metabolic effects including protection against diet-induced obesity and normalisation of glucose sensitivity associated with a shift to increased fat metabolism in the muscles.

Effects of transgenic methionine sulfoxide reductase A (MsrA expression on lifespan and age-dependent changes in metabolic function in mice

Directory of Open Access Journals (Sweden)

Adam B. Salmon

2016-12-01

Full Text Available Mechanisms that preserve and maintain the cellular proteome are associated with long life and healthy aging. Oxidative damage is a significant contributor to perturbation of proteostasis and is dealt with by the cell through regulation of antioxidants, protein degradation, and repair of oxidized amino acids. Methionine sulfoxide reductase A (MsrA repairs oxidation of free- and protein-bound methionine residues through enzymatic reduction and is found in both the cytosol and the mitochondria. Previous studies in Drosophila have shown that increasing expression of MsrA can extend longevity. Here we test the effects of increasing MsrA on longevity and healthy aging in two transgenic mouse models. We show that elevated expression of MsrA targeted specifically to the cytosol reduces the rate of age-related death in female mice when assessed by Gompertz analysis. However, neither cytosolic nor mitochondrial MsrA overexpression extends lifespan when measured by log-rank analysis. In mice with MsrA overexpression targeted to the mitochondria, we see evidence for improved insulin sensitivity in aged female mice. With these and our previous data, we conclude that the increasing MsrA expression in mice has differential effects on aging and healthy aging that are dependent on the target of its subcellular localization.

Over-expression of two different forms of the alpha-secretase ADAM10 affects learning and memory in mice.

Science.gov (United States)

Schmitt, Ulrich; Hiemke, Christoph; Fahrenholz, Falk; Schroeder, Anja

2006-12-15

Members of the ADAM family (adisintegrin and metalloprotease) are the main candidates for physiologically relevant alpha-secretases. The alpha-secretase cleaves in the non-amyloidogenic pathway the amyloid precursor protein within the region of the Abeta peptides preventing their aggregation in the brain. The increase of alpha-secretase activity in the brain provides a plausible strategy to prevent Abeta formation. Concerning this possibility two transgenic mouse lines (FVB/N) have been created: mice over-expressing the bovine form of the alpha-secretase (ADAM10) and mice over-expressing an inactive form of the alpha-secretase (ADAM10-E348A-HA; ADAM10-dn). For behavioral examination a F1 generation of transgenic mice (C57Bl/6 x FVB/N (tg)) was generated and compared to wild type F1 generation (C57Bl/6 x FVB/N). Behavior was characterized in the following tasks: standard open field, enriched open field, elevated plus-maze, and the Morris water maze hidden platform task. Concerning basal activity, exploration, and anxiety, transgenic mice behaved similar to controls. With respect to learning and memory both transgenic lines showed a significant deficit compared to controls. ADAM10 mice however, showed thigmotaxis with passive floating behavior in the Morris water maze indicating differences in motivation, whereas, ADAM10-dn mice displayed an inconspicuous but limited goal-directed search pattern. Thus variation of the enzymatic activity of alpha-secretase ADAM10 alters learning and memory differentially. Nevertheless, it could be concluded that both, ADAM10 and ADAM10-dn mice are suitable control mice for the assessment of alpha-secretase-related effects in animal models of Alzheimer's disease.

Erythropoietin over-expression protects against diet-induced obesity in mice through increased fat oxidation in muscles

DEFF Research Database (Denmark)

Hojman, Pernille; Brolin, Camilla; Gissel, Hanne

2009-01-01

patients. Thus we applied the EPO over-expression model to investigate the metabolic effect of EPO in vivo.At 12 weeks, EPO expression resulted in a 23% weight reduction (Pobese mice; thus the mice weighed 21.9+/-0.8 g (control, normal diet,) 21.9+/-1.4 g (EPO, normal diet), 35.......3+/-3.3 g (control, high-fat diet) and 28.8+/-2.6 g (EPO, high-fat diet). Correspondingly, DXA scanning revealed that this was due to a 28% reduction in adipose tissue mass.The decrease in adipose tissue mass was accompanied by a complete normalisation of fasting insulin levels and glucose tolerance......-physiological levels has substantial metabolic effects including protection against diet-induced obesity and normalisation of glucose sensitivity associated with a shift to increased fat metabolism in the muscles....

Parvalbumin-expressing ependymal cells in rostral lateral ventricle wall adhesions contribute to aging-related ventricle stenosis in mice.

Science.gov (United States)

Filice, Federica; Celio, Marco R; Babalian, Alexandre; Blum, Walter; Szabolcsi, Viktoria

2017-10-15

Aging-associated ependymal-cell pathologies can manifest as ventricular gliosis, ventricle enlargement, or ventricle stenosis. Ventricle stenosis and fusion of the lateral ventricle (LV) walls is associated with a massive decline of the proliferative capacities of the stem cell niche in the affected subventricular zone (SVZ) in aging mice. We examined the brains of adult C57BL/6 mice and found that ependymal cells located in the adhesions of the medial and lateral walls of the rostral LVs upregulated parvalbumin (PV) and displayed reactive phenotype, similarly to injury-reactive ependymal cells. However, PV+ ependymal cells in the LV-wall adhesions, unlike injury-reactive ones, did not express glial fibrillary acidic protein. S100B+/PV+ ependymal cells found in younger mice diminished in the LV-wall adhesions throughout aging. We found that periventricular PV-immunofluorescence showed positive correlation to the grade of LV stenosis in nonaged mice (wall adhesions and LV stenosis was significantly lower in mid-aged (>10-month-old) PV-knock out (PV-KO) mice. This suggests an involvement of PV+ ependymal cells in aging-associated ventricle stenosis. Additionally, we observed a time-shift in microglial activation in the LV-wall adhesions between age-grouped PV-KO and wild-type mice, suggesting a delay in microglial activation when PV is absent from ependymal cells. Our findings implicate that compromised ependymal cells of the adhering ependymal layers upregulate PV and display phenotype shift to "reactive" ependymal cells in aging-related ventricle stenosis; moreover, they also contribute to the progression of LV-wall fusion associated with a decline of the affected SVZ-stem cell niche in aged mice. © 2017 Wiley Periodicals, Inc.

Age-dependent modifications of AMPA receptor subunit expression levels and related cognitive effects in 3xTg-AD mice

Directory of Open Access Journals (Sweden)

Pamela eCantanelli

2014-08-01

Full Text Available GluA1, GluA2, GluA3, and GluA4 are the constitutive subunits of AMPA receptors (AMPARs, the major mediators of fast excitatory transmission in the mammalian central nervous system. Most AMPARs are Ca2+-impermeable because of the presence of the GluA2 subunit. GluA2 mRNA undergoes an editing process that results in a Q to R substitution, a key factor in the regulation of AMPAR Ca2+-permeability. AMPARs lacking GluA2 or containing the unedited subunit are permeable to Ca2+ and Zn2+. The phenomenon physiologically modulates synaptic plasticity while, in pathologic conditions, leads to increased vulnerability to excitotoxic neuronal death. Given the importance of these subunits, we have therefore evaluated possible associations between changes in expression levels of AMPAR subunits and development of cognitive deficits in 3xTg-AD mice, a widely investigated transgenic mouse model of Alzheimer’s disease. With qRT-PCR, we assayed hippocampal mRNA expression levels of GluA1-4 subunits occurring in young [3 months of age (m.o.a.] and old (12 m.o.a Tg-AD mice and made comparisons with levels found in age-matched wild type (WT mice. Efficiency of GluA2 RNA editing was also analyzed. All animals were cognitively tested for short- and long-term spatial memory with the Morris Water Maze (MWM navigation task. 3xTg-AD mice showed age-dependent decreases of mRNA levels for all the AMPAR subunits, with the exception of GluA2. Editing remained fully efficient with aging in 3xTg-AD and WT mice. A one-to-one correlation analysis between MWM performances and GluA1-4 mRNA expression profiles showed negative correlations between GluA2 levels and MWM performances in young 3xTg-AD mice. On the contrary, positive correlations between GluA2 mRNA and MWM performances were found in young WT mice. Our data suggest that increases of AMPARs that contain GluA1, GluA3, and GluA4 subunits may help in maintaining cognition in pre-symptomatic 3xTg-AD mice.

Polysaccharide Extracted from Laminaria japonica Delays Intrinsic Skin Aging in Mice

Directory of Open Access Journals (Sweden)

Longyuan Hu

2016-01-01

Full Text Available This study aimed to determine the effect of topically applied Laminaria polysaccharide (LP on skin aging. We applied ointment containing LP (10, 25, and 50 μg/g or vitamin E (10 μg/g to the dorsal skin of aging mice for 12 months and young control mice for 4 weeks. Electron microscopy analysis of skin samples revealed that LP increased dermal thickness and skin collagen content. Tissue inhibitor of metalloprotease- (TIMP- 1 expression was upregulated while that of matrix metalloproteinase- (MMP- 1 was downregulated in skin tissue of LP-treated as compared to untreated aging mice. Additionally, phosphorylation of c-Jun N-terminal kinase (JNK and p38 was higher in aging skin than in young skin, while LP treatment suppressed phospho-JNK expression. LP application also enhanced the expression of antioxidative enzymes in skin tissue, causing a decrease in malondialdehyde levels and increases in superoxide dismutase, catalase, and glutathione peroxidase levels relative to those in untreated aging mice. These results indicate that LP inhibits MMP-1 expression by preventing oxidative stress and JNK phosphorylation, thereby delaying skin collagen breakdown during aging.

The Brewed Rice Vinegar Kurozu Increases HSPA1A Expression and Ameliorates Cognitive Dysfunction in Aged P8 Mice.

Directory of Open Access Journals (Sweden)

Hiroaki Kanouchi

Full Text Available Kurozu is a traditional Japanese rice vinegar. During fermentation and aging of the Kurozu liquid in an earthenware jar over 1 year, a solid residue called Kurozu Moromi is produced. In the present study, we evaluated whether concentrated Kurozu or Kurozu Moromi could ameliorate cognitive dysfunction in the senescence-accelerated P8 mouse. Senescence-accelerated P8 mice were fed 0.25% (w/w concentrated Kurozu or 0.5% (w/w Kurozu Moromi for 4 or 25 weeks. Kurozu suppressed cognitive dysfunction and amyloid accumulation in the brain, while Kurozu Moromi showed a tendency to ameliorate cognitive dysfunction, but the effect was not significant. We hypothesize that concentrated Kurozu has an antioxidant effect; however, the level of lipid peroxidation in the brain did not differ in senescence-accelerated P8 mice. DNA microarray analysis indicated that concentrated Kurozu increased HSPA1A mRNA expression, a protein that prevents protein misfolding and aggregation. The increase in HSPA1A expression by Kurozu was confirmed using quantitative real-time PCR and immunoblotting methods. The suppression of amyloid accumulation by concentrated Kurozu may be associated with HSPA1A induction. However, concentrated Kurozu could not increase HSPA1A expression in mouse primary neurons, suggesting it may not directly affect neurons.

Mice with GFAP-targeted loss of neurofibromin demonstrate increased axonal MET expression with aging.

Science.gov (United States)

Su, Weiping; Xing, Rubing; Guha, Abhijit; Gutmann, David H; Sherman, Larry S

2007-05-01

Neurofibromatosis 1 (NF1) is a common genetic disease that predisposes patients to peripheral nerve tumors and central nervous system (CNS) abnormalities including low-grade astrocytomas and cognitive disabilities. Using mice with glial fibrillary acidic protein (GFAP)-targeted Nf1 loss (Nf1(GFAP)CKO mice), we found that Nf1(-/-) astrocytes proliferate faster and are more invasive than wild-type astrocytes. In light of our previous finding that aberrant expression of the MET receptor tyrosine kinase contributes to the invasiveness of human NF1-associated malignant peripheral nerve sheath tumors, we sought to determine whether MET expression is aberrant in the brains of Nf1 mutant mice. We found that Nf1(-/-) astrocytes express slightly more MET than wild-type cells in vitro, but do not express elevated MET in situ. However, fiber tracts containing myelinated axons in the hippocampus, midbrain, cerebral cortex, and cerebellum express higher than normal levels of MET in older (> or =6 months) Nf1(GFAP)CKO mice. Both Nf1(GFAP)CKO and wild-type astrocytes induced MET expression in neurites of wild-type hippocampal neurons in vitro, suggesting that astrocyte-derived signals may induce MET in Nf1 mutant mice. Because the Nf1 gene product functions as a RAS GTPase, we examined MET expression in the brains of mice with GFAP-targeted constitutively active forms of RAS. MET was elevated in axonal fiber tracts in mice with active K-RAS but not H-RAS. Collectively, these data suggest that loss of Nf1 in either astrocytes or GFAP(+) neural progenitor cells results in increased axonal MET expression, which may contribute to the CNS abnormalities in children and adults with NF1. (c) 2007 Wiley-Liss, Inc.

Cognition, learning behaviour and hippocampal synaptic plasticity are not disrupted in mice over-expressing the cholesterol transporter ABCG1

Directory of Open Access Journals (Sweden)

Eadie Brennan D

2009-02-01

Full Text Available Abstract Background Cognitive deficits are a hallmark feature of both Down Syndrome (DS and Alzheimer's Disease (AD. Extra copies of the genes on chromosome 21 may also play an important role in the accelerated onset of AD in DS individuals. Growing evidence suggests an important function for cholesterol in the pathogenesis of AD, particularly in APP metabolism and production of Aβ peptides. The ATP-Binding Cassette-G1 (ABCG1 transporter is located on chromosome 21, and participates in the maintenance of tissue cholesterol homeostasis. Results To assess the role of ABCG1 in DS-related cognition, we evaluated the cognitive performance of mice selectively over-expressing the ABCG1 gene from its endogenous regulatory signals. Both wild-type and ABCG1 transgenic mice performed equivalently on several behavioral tests, including measures of anxiety, as well as on reference and working memory tasks. No deficits in hippocampal CA1 synaptic plasticity as determined with electrophysiological studies were apparent in mice over-expressing ABCG1. Conclusion These findings indicate that although ABCG1 may play a role in maintaining cellular or tissue cholesterol homeostasis, it is unlikely that excess ABCG1 expression contributes to the cognitive deficits in DS individuals.

Effects of ibuprofen on cognition and NMDA receptor subunit expression across aging.

Science.gov (United States)

Márquez Loza, Alejandra; Elias, Valerie; Wong, Carmen P; Ho, Emily; Bermudez, Michelle; Magnusson, Kathy R

2017-03-06

Age-related declines in long- and short-term memory show relationships to decreases in N-methyl-d-aspartate (NMDA) receptor expression, which may involve inflammation. This study was designed to determine effects of an anti-inflammatory drug, ibuprofen, on cognitive function and NMDA receptor expression across aging. Male C57BL/6 mice (ages 5, 14, 20, and 26months) were fed ibuprofen (375ppm) in NIH31 diet or diet alone for 6weeks prior to testing. Behavioral testing using the Morris water maze showed that older mice performed significantly worse than younger in spatial long-term memory, reversal, and short-term memory tasks. Ibuprofen enhanced overall performance in the short-term memory task, but this appeared to be more related to improved executive function than memory. Ibuprofen induced significant decreases over all ages in the mRNA densities for GluN2B subunit, all GluN1 splice variants, and GluN1-1 splice forms in the frontal cortex and in protein expression of GluN2A, GluN2B and GluN1 C2' cassettes in the hippocampus. GluN1-3 splice form mRNA and C2' cassette protein were significantly increased across ages in frontal lobes of ibuprofen-treated mice. Ibuprofen did not alter expression of pro-inflammatory cytokines IL-1β and TNFα, but did reduce the area of reactive astrocyte immunostaining in frontal cortex of aged mice. Enhancement in executive function showed a relationship to increased GluN1-3 mRNA and decreased gliosis. These findings suggest that inflammation may play a role in executive function declines in aged animals, but other effects of ibuprofen on NMDA receptors appeared to be unrelated to aging or inflammation. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Antidepressive and BDNF effects of enriched environment treatment across ages in mice lacking BDNF expression through promoter IV

Science.gov (United States)

Jha, S; Dong, B E; Xue, Y; Delotterie, D F; Vail, M G; Sakata, K

2016-01-01

Reduced promoter IV-driven expression of brain-derived neurotrophic factor (BDNF) is implicated in stress and major depression. We previously reported that defective promoter IV (KIV) caused depression-like behavior in young adult mice, which was reversed more effectively by enriched environment treatment (EET) than antidepressants. The effects of promoter IV-BDNF deficiency and EET over the life stages remain unknown. Since early-life development (ED) involves dynamic epigenetic processes, we hypothesized that EET during ED would provide maximum antidepressive effects that would persist later in life due to enhanced, long-lasting BDNF induction. We tested this hypothesis by determining EET effects across three life stages: ED (0–2 months), young adult (2–4 months), and old adult (12–14 months). KIV mice at all life stages showed depression-like behavior in the open-field and tail-suspension tests compared with wild-type mice. Two months of EET reduced depression-like behavior in ED and young adult, but not old adult mice, with the largest effect in ED KIV mice. This effect lasted for 1 month after discontinuance of EET only in ED mice. BDNF protein induction by EET in the hippocampus and frontal cortex was also the largest in ED mice and persisted only in the hippocampus of ED KIV mice after discontinuance of EET. No gender-specific effects were observed. The results suggest that defective promoter IV causes depression-like behavior, regardless of age and gender, and that EET during ED is particularly beneficial to individuals with promoter IV-BDNF deficiency, while additional treatment may be needed for older adults. PMID:27648918

Aging Selectively Modulates Vitamin C Transporter Expression Patterns in the Kidney.

Science.gov (United States)

Forman, Katherine; Martínez, Fernando; Cifuentes, Manuel; Bertinat, Romina; Salazar, Katterine; Nualart, Francisco

2017-09-01

In the kidney, vitamin C is reabsorbed from the glomerular ultrafiltrate by sodium-vitamin C cotransporter isoform 1 (SVCT1) located in the brush border membrane of the proximal tubules. Although we know that vitamin C levels decrease with age, the adaptive physiological mechanisms used by the kidney for vitamin C reabsorption during aging remain unknown. In this study, we used an animal model of accelerated senescence (SAMP8 mice) to define the morphological alterations and aging-induced changes in the expression of vitamin C transporters in renal tissue. Aging induced significant morphological changes, such as periglomerular lymphocytic infiltrate and glomerular congestion, in the kidneys of SAMP8 mice, although no increase in collagen deposits was observed using 2-photon microscopy analysis and second harmonic generation. The most characteristic histological alteration was the dilation of intracellular spaces in the basolateral region of proximal tubule epithelial cells. Furthermore, a combination of laser microdissection, qRT-PCR, and immunohistochemical analyses allowed us to determine that SVCT1 expression specifically increased in the proximal tubules from the outer strip of the outer medulla (segment S3) and cortex (segment S2) during aging and that these tubules also express GLUT1. We conclude that aging modulates vitamin C transporter expression and that renal over-expression of SVCT1 enhances vitamin C reabsorption in aged animals that may synthesize less vitamin C. J. Cell. Physiol. 232: 2418-2426, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Expression patterns of odorant receptors and response properties of olfactory sensory neurons in aged mice.

Science.gov (United States)

Lee, Anderson C; Tian, Huikai; Grosmaitre, Xavier; Ma, Minghong

2009-10-01

The sense of smell deteriorates in normal aging, but the underling mechanisms are still elusive. Here we investigated age-related alterations in expression patterns of odorant receptor (OR) genes and functional properties of olfactory sensory neurons (OSNs)-2 critical factors that define the odor detection threshold in the olfactory epithelium. Using in situ hybridization for 9 representative OR genes, we compared the cell densities of each OR in coronal nose sections at different ages (3-27 months). The cell density for different ORs peaked at different time points and a decline was observed for 6 of 9 ORs at advanced ages. Using patch clamp recordings, we then examined the odorant responses of individual OSNs coexpressing a defined OR (MOR23) and green fluorescent protein. The MOR23 neurons recorded from aged animals maintained a similar sensitivity and dynamic range in response to the cognate odorant (lyral) as those from younger mice. The results indicate that although the cell densities of OSNs expressing certain types of ORs decline at advanced ages, individual OSNs can retain their sensitivity. The implications of these findings in age-related olfactory deterioration are discussed.

Reduction in podocyte SIRT1 accelerates kidney injury in aging mice.

Science.gov (United States)

Chuang, Peter Y; Cai, Weijing; Li, Xuezhu; Fang, Lu; Xu, Jin; Yacoub, Rabi; He, John Cijiang; Lee, Kyung

2017-09-01

Both the incidence and prevalence of chronic kidney disease are increasing in the elderly population. Although aging is known to induce kidney injury, the underlying molecular mechanisms remain unclear. Sirtuin 1 (Sirt1), a longevity gene, is known to protect kidney cell injury from various cellular stresses. In previous studies, we showed that the podocyte-specific loss of Sirt1 aggravates diabetic kidney injury. However, the role of Sirt1 in aging-induced podocyte injury is not known. Therefore, in this study we sought to determine the effects of podocyte-specific reduction of Sirt1 in age-induced kidney injury. We employed the inducible podocyte-specific Sirt1 knockdown mice that express shRNA against Sirt1 (Pod-Sirt1 RNAi ) and control mice that express shRNA for luciferase (Pod-Luci RNAi ). We found that reduction of podocyte Sirt1 led to aggravated aging-induced glomerulosclerosis and albuminuria. In addition, urinary level of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative stress, was markedly increased in aged Pod-Sirt1 RNAi mice compared with aged Pod-Luci RNAi mice. Although podocyte-specific markers decreased in aged mice compared with the young controls, the decrease was further exacerbated in aged Pod-Sirt1 RNAi compared with Pod-Luci RNAi mice. Interestingly, expression of cellular senescence markers was significantly higher in the glomeruli of Pod-Sirt1 RNAi mice than Pod-Luci RNAi mice, suggesting that cellular senescence may contribute to podocyte loss in aging kidneys. Finally, we confirmed that Pod-Sirt1 RNAi glomeruli were associated with reduced activation of the transcription factors peroxisome proliferator-activated receptor (PPAR)-α coactivador-1 (PGC1α)/PPARγ, forkhead box O (FOXO)3, FOXO4, and p65 NF-κB, through SIRT1-mediated deacetylation. Together, our data suggest that SIRT1 may be a potential therapeutic target to treat patients with aging-related kidney disease.

Effectiveness of BCG vaccination to aged mice

Directory of Open Access Journals (Sweden)

Ito Tsukasa

2010-09-01

Full Text Available Abstract Background The tuberculosis (TB still increases in the number of new cases, which is estimated to approach 10 million in 2010. The number of aged people has been growing all over the world. Ageing is one of risk factors in tuberculosis because of decreased immune responses in aged people. Mycobacterium bovis Bacillus Calmette Guérin (BCG is a sole vaccine currently used for TB, however, the efficacy of BCG in adults is still a matter of debate. Emerging the multidrug resistant Mycobacterium tuberculosis (MDR-TB make us to see the importance of vaccination against TB in new light. In this study, we evaluated the efficacy of BCG vaccination in aged mice. Results The Th1 responses, interferon-γ production and interleukin 2, in BCG inoculated aged mice (24-month-old were comparable to those of young mice (4- to 6-week-old. The protection activity of BCG in aged mice against Mycobacterium tuberculosis H37Rv was also the same as young mice. Conclusion These findings suggest that vaccination in aged generation is still effective for protection against tuberculosis.

Cigarette Smoke-Induced Cell Death Causes Persistent Olfactory Dysfunction in Aged Mice

Directory of Open Access Journals (Sweden)

Rumi Ueha

2018-06-01

Full Text Available Introduction: Exposure to cigarette smoke is a cause of olfactory dysfunction. We previously reported that in young mice, cigarette smoke damaged olfactory progenitors and decreased mature olfactory receptor neurons (ORNs, then, mature ORNs gradually recovered after smoking cessation. However, in aged populations, the target cells in ORNs by cigarette smoke, the underlying molecular mechanisms by which cigarette smoke impairs the regenerative ORNs, and the degree of ORN regeneration after smoking cessation remain unclear.Objectives: To explore the effects of cigarette smoke on the ORN cell system using an aged mouse model of smoking, and to investigate the extent to which smoke-induced damage to ORNs recovers following cessation of exposure to cigarette smoke in aged mice.Methods: We intranasally administered a cigarette smoke solution (CSS to 16-month-old male mice over 24 days, then examined ORN existence, cell survival, changes of inflammatory cytokines in the olfactory epithelium (OE, and olfaction using histological analyses, gene analyses and olfactory habituation/dishabituation tests.Results: CSS administration reduced the number of mature ORNs in the OE and induced olfactory dysfunction. These changes coincided with an increase in the number of apoptotic cells and Tumor necrosis factor (TNF expression and a decrease in Il6 expression. Notably, the reduction in mature ORNs did not recover even on day 28 after cessation of treatment with CSS, resulting in persistent olfactory dysfunction.Conclusion: In aged mice, by increasing ORN death, CSS exposure could eventually overwhelm the regenerative capacity of the OE, resulting in continued reduction in the number of mature ORNs and olfactory dysfunction.

Biosystems Study of the Molecular Networks Underlying Hippocampal Aging Progression and Anti-aging Treatment in Mice

Directory of Open Access Journals (Sweden)

Jiao Wang

2017-12-01

Full Text Available Aging progression is a process that an individual encounters as they become older, and usually results from a series of normal physiological changes over time. The hippocampus, which contributes to the loss of spatial and episodic memory and learning in older people, is closely related to the detrimental effects of aging at the morphological and molecular levels. However, age-related genetic changes in hippocampal molecular mechanisms are not yet well-established. To provide additional insight into the aging process, differentially-expressed genes of 3- versus 24- and 29-month old mice were re-analyzed. The results revealed that a large number of immune and inflammatory response-related genes were up-regulated in the aged hippocampus, and membrane receptor-associated genes were down-regulated. The down-regulation of transmembrane receptors may indicate the weaker perception of environmental exposure in older people, since many transmembrane proteins participate in signal transduction. In addition, molecular interaction analysis of the up-regulated immune genes indicated that the hub gene, Ywhae, may play essential roles in immune and inflammatory responses during aging progression, as well as during hippocampal development. Our biological experiments confirmed the conserved roles of Ywhae and its partners between human and mouse. Furthermore, comparison of microarray data between advanced-age mice treated with human umbilical cord blood plasma protein and the phosphate-buffered saline control showed that the genes that contribute to the revitalization of advanced-age mice are different from the genes induced by aging. These results implied that the revitalization of advanced-age mice is not a simple reverse process of normal aging progression. Our data assigned novel roles of genes during aging progression and provided further theoretic evidence for future studies exploring the underlying mechanisms of aging and anti-aging-related disease

RAGE-dependent activation of gene expression of superoxide dismutase and vanins by AGE-rich extracts in mice cardiac tissue and murine cardiac fibroblasts.

Science.gov (United States)

Leuner, Beatrice; Ruhs, Stefanie; Brömme, Hans-Jürgen; Bierhaus, Angelika; Sel, Saadettin; Silber, Rolf-Edgar; Somoza, Veronika; Simm, Andreas; Nass, Norbert

2012-10-01

Advanced glycation end products (AGEs) are stable compounds formed from initial Maillard reaction products. They are considered as markers for ageing and often associated with age-related, degenerative diseases. Bread crust represents an established model for nutritional compounds rich in AGEs and is able to induce antioxidative defense genes such as superoxide dismutases and vanins in cardiac cells. The aim of this study was to investigate to what extend the receptor for AGEs (RAGE) contributes to this response. Signal transduction in response to bread crust extract was analysed in cardiac fibroblasts derived from C57/B6-NCrl (RAGE +/+) and the corresponding RAGE-knock out C57/B6-NCrl mouse strain (RAGE -/-). Activation of superoxide dismutases in animals was then analysed upon bread crust feeding in these two mice strains. Cardiac fibroblasts from RAGE -/- mice did not express RAGE, but the expression of AGER-1 and AGER-3 was up-regulated, whereas the expression of SR-B1 was down-regulated. RAGE -/- cells were less sensitive to BCE in terms of MAP-kinase phosphorylation and NF-κB reporter gene activation. Bread crust extract induced mRNA levels of MnSOD and Vnn-1 were also reduced in RAGE -/- cells, whereas Vnn-3 mRNA accumulation seemed to be RAGE receptor independent. In bread crust feeding experiments, RAGE -/- mice did not exhibit an activation of MnSOD-mRNA and -protein accumulation as observed for the RAGE +/+ animals. In conclusion, RAGE was clearly a major factor for the induction of antioxidant defense signals derived from bread crust in cardiac fibroblast and mice. Nevertheless higher doses of bread crust extract could overcome the RAGE dependency in cell cultures, indicating that additional mechanisms are involved in BCE-mediated activation of SOD and vanin expression.

Cold hypersensitivity increases with age in mice with sickle cell disease

Science.gov (United States)

Zappia, Katherine J.; Garrison, Sheldon R.; Hillery, Cheryl A.; Stucky, Cheryl L.

2014-01-01

Sickle cell disease (SCD) is associated with acute vaso-occlusive crises that trigger painful episodes and frequently involves ongoing, chronic pain. Additionally, both humans and mice with SCD experience heighted cold sensitivity. However, studies have not addressed the mechanism(s) underlying the cold sensitization, nor its progression with age. Here we measured thermotaxis behavior in young and aged mice with severe SCD. Sickle mice had a marked increase in cold sensitivity measured by a cold preference test. Further, cold hypersensitivity worsened with advanced age. We assessed whether enhanced peripheral input contributes to the chronic cold pain behavior by recording from C fibers, many of which are cold-sensitive, in skin-nerve preparations. We observed that C fibers from sickle mice displayed a shift to warmer (more sensitive) cold-detection thresholds. To address mechanisms underlying the cold sensitization in primary afferent neurons, we quantified mRNA expression levels for ion channels thought to be involved in cold detection. These included the Transient Receptor Potential Melastatin 8 (Trpm8) and TRP Ankyrin 1 (Trpa1) channels, as well as the two-pore domain potassium channels, TREK-1 (Kcnk2), TREK-2 (Kcnk4), and TRAAK (Kcnk10). Surprisingly, transcript expression levels of all of these channels were comparable between sickle and control mice. We further examined transcript expression of 83 additional pain-related genes and found increased mRNA levels for endothelin 1 and tachykinin receptor 1. These factors may contribute to hypersensitivity in sickle mice at both the afferent and behavioral levels. Sensory neurons from sickle cell disease mice are sensitized to cold, mirroring behavioral observations, and have increased expression of endothelin 1 and tachykinin receptor 1. PMID:24953902

Aged Tg2576 mice are impaired on social memory and open field habituation tests.

Science.gov (United States)

Deacon, R M J; Koros, E; Bornemann, K D; Rawlins, J N P

2009-02-11

In a previous publication [Deacon RMJ, Cholerton LL, Talbot K, Nair-Roberts RG, Sanderson DJ, Romberg C, et al. Age-dependent and -independent behavioral deficits in Tg2576 mice. Behav Brain Res 2008;189:126-38] we found that very few cognitive tests were suitable for demonstrating deficits in Tg2576 mice, an amyloid over-expression model of Alzheimer's disease, even at 23 months of age. However, in a retrospective analysis of a separate project on these mice, tests of social memory and open field habituation revealed large cognitive impairments. Controls showed good open field habituation, but Tg2576 mice were hyperactive and failed to habituate. In the test of social memory for a juvenile mouse, controls showed considerably less social investigation on the second meeting, indicating memory of the juvenile, whereas Tg2576 mice did not show this decrement.As a control for olfactory sensitivity, on which social memory relies, the ability to find a food pellet hidden under wood chip bedding was assessed. Tg2576 mice found the pellet as quickly as controls. As this test requires digging ability, this was independently assessed in tests of burrowing and directly observed digging. In line with previous results and the hippocampal dysfunction characteristic of aged Tg2576 mice, they both burrowed and dug less than controls.

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...

Aging-associated changes in motor axon voltage-gated Na+ channel function in mice

DEFF Research Database (Denmark)

Moldovan, Mihai; Rosberg, Mette Romer; Alvarez Herrero, Susana

2016-01-01

the functional impairment. The aim of the present study was to investigate the effect of regular aging on motor axon function with particular emphasis on Nav1.8. We compared tibial nerve conduction and excitability measures by threshold tracking in 12 months (mature) and 20 months (aged) wild-type (WT) mice...... expression was found by immunohistochemistry. The depolarizing excitability features were absent in Nav1.8 null mice, and they were counteracted in WT mice by a Nav1.8 blocker. Our data suggest that alteration in voltage-gated Na+ channel isoform expression contributes to changes in motor axon function...

Safety and Efficacy of Scanning Ultrasound Treatment of Aged APP23 Mice

Directory of Open Access Journals (Sweden)

Gerhard Leinenga

2018-02-01

Full Text Available Deposition of amyloid-β (Aβ peptide leads to amyloid plaques that together with tau deposits characterize the brains of patients with Alzheimer's disease (AD. In modeling this pathology, transgenic animals such as the APP23 strain, that expresses a mutant form of the amyloid precursor protein found in familial cases of AD, have been instrumental. In previous studies, we have shown that repeated treatments with ultrasound in a scanning mode (termed scanning ultrasound or SUS were effective in removing Aβ and restoring memory functions, without the need for a therapeutic agent such as an Aβ antibody. Considering that age is the most important risk factor for AD, we extended this study in which the mice were only 12 months old at the time of treatment by assessing a cohort of 2 year-old mice. Interestingly, at this age, APP23 mice are characterized by cerebral amyloid angiopathy (CAA and the presence of occasional microbleeds. We found that SUS in aged mice that have been exposed to four SUS sessions that were spread out over 8 weeks and analyzed 4 weeks later did not show evidence of increased CAA or microbleeds. Furthermore, amyloid was reduced as assessed by methoxy-XO4 fluorescence. In addition, plaque-associated microglia were more numerous in SUS treated mice. Together this adds to the notion that SUS may be a treatment modality for human neurodegenerative diseases.

Differential expression of a novel seven transmembrane domain protein in epididymal fat from aged and diabetic mice.

Science.gov (United States)

Yang, H; Egan, J M; Rodgers, B D; Bernier, M; Montrose-Rafizadeh, C

1999-06-01

To identify novel seven transmembrane domain proteins from 3T3-L1 adipocytes, we used PCR to amplify 3T3-L1 adipocyte complementary DNA (cDNA) with primers homologous to the N- and C-termini of pancreatic glucagon-like peptide-1 (GLP-1) receptor. We screened a cDNA library prepared from fully differentiated 3T3-L1 adipocytes using a 500-bp cDNA PCR product probe. Herein describes the isolation and characterization of a 1.6-kb cDNA clone that encodes a novel 298-amino acid protein that we termed TPRA40 (transmembrane domain protein of 40 kDa regulated in adipocytes). TPRA40 has seven putative transmembrane domains and shows little homology with the known GLP-1 receptor or with other G protein-coupled receptors. The levels of TPRA40 mRNA and protein were higher in 3T3-L1 adipocytes than in 3T3-L1 fibroblasts. TPRA40 is present in a number of mouse and human tissues. Interestingly, TPRA40 mRNA levels were significantly increased by 2- to 3-fold in epididymal fat of 24-month-old mice vs. young controls as well as in db/db and ob/ob mice vs. nondiabetic control littermates. No difference in TPRA40 mRNA levels was observed in brain, heart, skeletal muscle, liver, or kidney. Furthermore, no difference in TPRA40 expression was detected in brown fat of ob/ob mice when compared with age-matched controls. Taken together, these data suggest that TPRA40 represents a novel membrane-associated protein whose expression in white adipose tissue is altered with aging and type 2 diabetes.

Expression of Sirtuins in the Retinal Neurons of Mice, Rats, and Humans

Directory of Open Access Journals (Sweden)

Hongdou Luo

2017-11-01

Full Text Available Sirtuins are a class of histone deacetylases (HDACs that have been shown to regulate a range of pathophysiological processes such as cellular aging, inflammation, metabolism, and cell proliferation. There are seven mammalian Sirtuins (SIRT1-7 that play important roles in stress response, aging, and neurodegenerative diseases. However, the location and function of Sirtuins in neurons are not well defined. This study assessed the retinal expression of Sirtuins in mice, rats, and humans and measured the expression of Sirtuins in aged and injured retinas. Expression of all 7 Sirtuins was confirmed by Western blot and Real-Time PCR analysis in all three species. SIRT1 is highly expressed in mouse, rat, and human retinas, whereas SIRT2-7 expression was relatively lower in human retinas. Immunofluorescence was also used to examine the expression and localization of Sirtuins in rat retinal neurons. Importantly, we demonstrate a marked reduction of SIRT1 expression in aged retinal neurons as well as retinas injured by acute ischemia-reperfusion. On the other hand, none of the other Sirtuins exhibit any significant age-related changes in expression except for SIRT5, which was significantly higher in the retinas of adults compared to both young and aged rats. Our work presents the first composite analysis of Sirtuins in the retinal neurons of mice, rats, and humans, and suggests that increasing the expression and activity of SIRT1 may be beneficial for the treatment of glaucoma and other age-related eye dysfunction.

Tetracycline-inducible system for regulation of skeletal muscle-specific gene expression in transgenic mice

Science.gov (United States)

Grill, Mischala A.; Bales, Mark A.; Fought, Amber N.; Rosburg, Kristopher C.; Munger, Stephanie J.; Antin, Parker B.

2003-01-01

Tightly regulated control of over-expression is often necessary to study one aspect or time point of gene function and, in transgenesis, may help to avoid lethal effects and complications caused by ubiquitous over-expression. We have utilized the benefits of an optimized tet-on system and a modified muscle creatine kinase (MCK) promoter to generate a skeletal muscle-specific, doxycycline (Dox) controlled over-expression system in transgenic mice. A DNA construct was generated in which the codon optimized reverse tetracycline transactivator (rtTA) was placed under control of a skeletal muscle-specific version of the mouse MCK promoter. Transgenic mice containing this construct expressed rtTA almost exclusively in skeletal muscles. These mice were crossed to a second transgenic line containing a bi-directional promoter centered on a tet responder element driving both a luciferase reporter gene and a tagged gene of interest; in this case the calpain inhibitor calpastatin. Compound hemizygous mice showed high level, Dox dependent muscle-specific luciferase activity often exceeding 10,000-fold over non-muscle tissues of the same mouse. Western and immunocytochemical analysis demonstrated similar Dox dependent muscle-specific induction of the tagged calpastatin protein. These findings demonstrate the effectiveness and flexibility of the tet-on system to provide a tightly regulated over-expression system in adult skeletal muscle. The MCKrtTA transgenic lines can be combined with other transgenic responder lines for skeletal muscle-specific over-expression of any target gene of interest.

Age-Related Decrease in Stress Responsiveness and Proactive Coping in Male Mice.

Science.gov (United States)

Oh, Hee-Jin; Song, Minah; Kim, Young Ki; Bae, Jae Ryong; Cha, Seung-Yun; Bae, Ji Young; Kim, Yeongmin; You, Minsu; Lee, Younpyo; Shim, Jieun; Maeng, Sungho

2018-01-01

Coping is a strategic approach to dealing with stressful situations. Those who use proactive coping strategies tend to accept changes and act before changes are expected. In contrast, those who use reactive coping are less flexible and more likely to act in response to changes. However, little research has assessed how coping style changes with age. This study investigated age-related changes in coping strategies and stress responsiveness and the influence of age on the processing of conditioned fear memory in 2-, 12- and 23-month-old male mice. Coping strategy was measured by comparing the escape latency in an active avoidance test and by comparing responses to a shock prod. The results showed that proactivity in coping response gradually decreased with age. Stress responsiveness, measured by stress-induced concentration of corticosterone, was also highest in 2-month-old mice and decreased with age. Consolidation of fear memory was highest in 12-month-old mice and was negatively correlated with the degree of stress responsiveness and proactivity in coping. Fear extinction did not differ among age groups and was not correlated with stress responsiveness or the proactivity of coping. However, the maintenance of extinct fear memory, which was best in 2-month-old mice and worst in 12-month-old mice, was negatively correlated with stress responsiveness but not with coping style. Age-dependent changes in the expression of glucocorticoid receptor (GR) and its regulatory co-chaperones, which are accepted mechanisms for stress hormone stimulation, were measured in the hippocampus. The expression of GR was increased at 12 months compared to other age groups. There were no differences in Hsp70 and BAG1 expression by age. These results can be summarized as follows: (1) stress responsiveness and proactivity in coping decreased with age class; (2) consolidation of fear memory was negatively correlated with both stress responsiveness and proactivity; however, maintenance of

Proteomic study on gender differences in aging kidney of mice

Directory of Open Access Journals (Sweden)

Cristobal Susana

2009-04-01

Full Text Available Abstract Background This study aims to analyze sex differences in mice aging kidney. We applied a proteomic technique based on subfractionation, and liquid chromatography coupled with 2-DE. Samples from male and female CD1-Swiss outbred mice from 28 weeks, 52 weeks, and 76 weeks were analysed by 2-DE, and selected proteins were identified by matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS. Results This proteomic analysis detected age-related changes in protein expression in 55 protein-spots, corresponding to 22 spots in males and 33 spots in females. We found a protein expression signature (PES of aging composed by 8 spots, common for both genders. The identified proteins indicated increases in oxidative and proteolytic proteins and decreases in glycolytic proteins, and antioxidant enzymes. Conclusion Our results provide insights into the gender differences associated to the decline of kidney function in aging. Thus, we show that proteomics can provide valuable information on age-related changes in expression levels of proteins and related modifications. This pilot study is still far from providing candidates for aging-biomarkers. However, we suggest that the analysis of these proteins could suggest mechanisms of cellular aging in kidney, and improve the kidney selection for transplantation.

Effects of strain and age on hepatic gene expression profiles in murine models of HFE-associated hereditary hemochromatosis.

Science.gov (United States)

Lee, Seung-Min; Loguinov, Alexandre; Fleming, Robert E; Vulpe, Christopher D

2015-01-01

Hereditary hemochromatosis is an iron overload disorder most commonly caused by a defect in the HFE gene. While the genetic defect is highly prevalent, the majority of individuals do not develop clinically significant iron overload, suggesting the importance of genetic modifiers. Murine hfe knockout models have demonstrated that strain background has a strong effect on the severity of iron loading. We noted that hepatic iron loading in hfe-/- mice occurs primarily over the first postnatal weeks (loading phase) followed by a timeframe of relatively static iron concentrations (plateau phase). We thus evaluated the effects of background strain and of age on hepatic gene expression in Hfe knockout mice (hfe-/-). Hepatic gene expression profiles were examined using cDNA microarrays in 4- and 8-week-old hfe-/- and wild-type mice on two different genetic backgrounds, C57BL/6J (C57) and AKR/J (AKR). Genes differentially regulated in all hfe-/- mice groups, compared with wild-type mice, including those involved in cell survival, stress and damage responses and lipid metabolism. AKR strain-specific changes in lipid metabolism genes and C57 strain-specific changes in cell adhesion and extracellular matrix protein genes were detected in hfe-/- mice. Mouse strain and age are each significantly associated with hepatic gene expression profiles in hfe-/- mice. These affects may underlie or reflect differences in iron loading in these mice.

Aging and cellular defense mechanisms: age-related changes in resistance of mice to Listeria monocytogenes.

OpenAIRE

Patel, P J

1981-01-01

Age-related changes in resistance of mice to infection with Listeria monocytogenes were investigated. One-month-old mice exhibited the least resistance, and the resistance level increased over the first few months to reach a maximum by 8 months. Increase in age thereafter was accompanied by a slow but progressive decrease in resistance. Thus, 50% lethal doses for 1-, 8-, and 24-month-old mice were 10(4.2), 10(6.6), and 10(5.2), respectively. In spite of differences in resistance, the growth o...

Joint dysfunction and functional decline in middle age myostatin null mice.

Science.gov (United States)

Guo, Wen; Miller, Andrew D; Pencina, Karol; Wong, Siu; Lee, Amanda; Yee, Michael; Toraldo, Gianluca; Jasuja, Ravi; Bhasin, Shalender

2016-02-01

Since its discovery as a potent inhibitor for muscle development, myostatin has been actively pursued as a drug target for age- and disease-related muscle loss. However, potential adverse effects of long-term myostatin deficiency have not been thoroughly investigated. We report herein that male myostatin null mice (mstn(-/-)), in spite of their greater muscle mass compared to wild-type (wt) mice, displayed more significant functional decline from young (3-6months) to middle age (12-15months) than age-matched wt mice, measured as gripping strength and treadmill endurance. Mstn(-/-) mice displayed markedly restricted ankle mobility and degenerative changes of the ankle joints, including disorganization of bone, tendon and peri-articular connective tissue, as well as synovial thickening with inflammatory cell infiltration. Messenger RNA expression of several pro-osteogenic genes was higher in the Achilles tendon-bone insertion in mstn(-/-) mice than wt mice, even at the neonatal age. At middle age, higher plasma concentrations of growth factors characteristic of excessive bone remodeling were found in mstn(-/-) mice than wt controls. These data collectively indicate that myostatin may play an important role in maintaining ankle and wrist joint health, possibly through negative regulation of the pro-osteogenic WNT/BMP pathway. Copyright © 2015 Elsevier Inc. All rights reserved.

Curcumin attenuates surgery-induced cognitive dysfunction in aged mice.

Science.gov (United States)

Wu, Xiang; Chen, Huixin; Huang, Chunhui; Gu, Xinmei; Wang, Jialing; Xu, Dilin; Yu, Xin; Shuai, Chu; Chen, Liping; Li, Shun; Xu, Yiguo; Gao, Tao; Ye, Mingrui; Su, Wei; Liu, Haixiong; Zhang, Jinrong; Wang, Chuang; Chen, Junping; Wang, Qinwen; Cui, Wei

2017-06-01

Post-operative cognitive dysfunction (POCD) is associated with elderly patients undergoing surgery. However, pharmacological treatments for POCD are limited. In this study, we found that curcumin, an active compound derived from Curcuma longa, ameliorated the cognitive dysfunction following abdominal surgery in aged mice. Further, curcumin prevented surgery-induced anti-oxidant enzyme activity. Curcumin also increased brain-derived neurotrophic factor (BDNF)-positive area and expression of pAkt in the brain, suggesting that curcumin activated BDNF signaling in aged mice. Furthermore, curcumin neutralized cholinergic dysfunction involving choline acetyltransferase expression induced by surgery. These results strongly suggested that curcumin prevented cognitive impairments via multiple targets, possibly by increasing the activity of anti-oxidant enzymes, activation of BDNF signaling, and neutralization of cholinergic dysfunction, concurrently. Based on these novel findings, curcumin might be a potential agent in POCD prophylaxis and treatment.

Hyperactive hypothalamus, motivated and non-distractible chronic overeating in ADAR2 transgenic mice.

Science.gov (United States)

Akubuiro, A; Bridget Zimmerman, M; Boles Ponto, L L; Walsh, S A; Sunderland, J; McCormick, L; Singh, M

2013-04-01

ADAR2 transgenic mice misexpressing the RNA editing enzyme ADAR2 (Adenosine Deaminase that act on RNA) show characteristics of overeating and experience adult onset obesity. Behavioral patterns and brain changes related to a possible addictive overeating in these transgenic mice were explored as transgenic mice display chronic hyperphagia. ADAR2 transgenic mice were assessed in their food preference and motivation to overeat in a competing reward environment with ad lib access to a running wheel and food. Metabolic activity of brain and peripheral tissue were assessed with [(18) F] fluorodeoxyglucose positron emission tomography (FDG-PET) and RNA expression of feeding related genes, ADAR2, dopamine and opiate receptors from the hypothalamus and striatum were examined. The results indicate that ADAR2 transgenic mice exhibit, (1) a food preference for diets with higher fat content, (2) significantly increased food intake that is non-distractible in a competing reward environment, (3) significantly increased messenger RNA (mRNA) expressions of ADAR2, serotonin 2C receptor (5HT2C R), D1, D2 and mu opioid receptors and no change in corticotropin-releasing hormone mRNAs and significantly reduced ADAR2 protein expression in the hypothalamus, (4) significantly increased D1 receptor and altered bioamines with no change in ADAR2, mu opioid and D2 receptor mRNA expression in the striatum and (5) significantly greater glucose metabolism in the hypothalamus, brain stem, right hippocampus, left and right mid brain regions and suprascapular peripheral tissue than controls. These results suggest that highly motivated and goal-oriented overeating behaviors of ADAR2 transgenic mice are associated with altered feeding, reward-related mRNAs and hyperactive brain mesolimbic region. Genes, Brain and Behavior © 2013 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

Aging-associated renal disease in mice is fructokinase dependent.

Science.gov (United States)

Roncal-Jimenez, Carlos A; Ishimoto, Takuji; Lanaspa, Miguel A; Milagres, Tamara; Hernando, Ana Andres; Jensen, Thomas; Miyazaki, Makoto; Doke, Tomohito; Hayasaki, Takahiro; Nakagawa, Takahiko; Marumaya, Shoichi; Long, David A; Garcia, Gabriela E; Kuwabara, Masanari; Sánchez-Lozada, Laura G; Kang, Duk-Hee; Johnson, Richard J

2016-10-01

Aging-associated kidney disease is usually considered a degenerative process associated with aging. Recently, it has been shown that animals can produce fructose endogenously, and that this can be a mechanism for causing kidney damage in diabetic nephropathy and in association with recurrent dehydration. We therefore hypothesized that low-level metabolism of endogenous fructose might play a role in aging-associated kidney disease. Wild-type and fructokinase knockout mice were fed a normal diet for 2 yr that had minimal (renal injury was amplified by provision of high-salt diet for 3 wk, as noted by the presence of glomerular hypertrophy, mesangial matrix expansion, and alpha smooth muscle actin expression, and with segmental thrombi. Fructokinase knockout mice were protected from renal injury both at baseline and after high salt intake (3 wk) compared with wild-type mice. This was associated with higher levels of active (phosphorylated serine 1177) endothelial nitric oxide synthase in their kidneys. These studies suggest that aging-associated renal disease might be due to activation of specific metabolic pathways that could theoretically be targeted therapeutically, and raise the hypothesis that aging-associated renal injury may represent a disease process as opposed to normal age-related degeneration.

Sox10 expressing cells in the lateral wall of the aged mouse and human cochlea.

Directory of Open Access Journals (Sweden)

Xinping Hao

Full Text Available Age-related hearing loss (presbycusis is a common human disorder, affecting one in three Americans aged 60 and over. Previous studies have shown that presbyacusis is associated with a loss of non-sensory cells in the cochlear lateral wall. Sox10 is a transcription factor crucial to the development and maintenance of neural crest-derived cells including some non-sensory cell types in the cochlea. Mutations of the Sox10 gene are known to cause various combinations of hearing loss and pigmentation defects in humans. This study investigated the potential relationship between Sox10 gene expression and pathological changes in the cochlear lateral wall of aged CBA/CaJ mice and human temporal bones from older donors. Cochlear tissues prepared from young adult (1-3 month-old and aged (2-2.5 year-old mice, and human temporal bone donors were examined using quantitative immunohistochemical analysis and transmission electron microscopy. Cells expressing Sox10 were present in the stria vascularis, outer sulcus and spiral prominence in mouse and human cochleas. The Sox10(+ cell types included marginal and intermediate cells and outer sulcus cells, including those that border the scala media and those extending into root processes (root cells in the spiral ligament. Quantitative analysis of immunostaining revealed a significant decrease in the number of Sox10(+ marginal cells and outer sulcus cells in aged mice. Electron microscopic evaluation revealed degenerative alterations in the surviving Sox10(+ cells in aged mice. Strial marginal cells in human cochleas from donors aged 87 and older showed only weak immunostaining for Sox10. Decreases in Sox10 expression levels and a loss of Sox10(+ cells in both mouse and human aged ears suggests an important role of Sox10 in the maintenance of structural and functional integrity of the lateral wall. A loss of Sox10(+ cells may also be associated with a decline in the repair capabilities of non-sensory cells in the

Redox susceptibility of SOD1 mutants is associated with the differential response to CCS over-expression in vivo.

Science.gov (United States)

Son, Marjatta; Fu, Qiao; Puttaparthi, Krishna; Matthews, Christina M; Elliott, Jeffrey L

2009-04-01

Over-expression of CCS in G93A SOD1 mice accelerates neurological disease and enhances mitochondrial pathology. We studied the effect of CCS over-expression in transgenic mice expressing G37R, G86R or L126Z SOD1 mutations in order to understand factors which influence mitochondrial dysfunction. Over-expression of CCS markedly decreased survival and produced mitochondrial vacuolation in G37R SOD1 mice but not in G86R or L126Z SOD1 mice. Moreover, CCS/G37R SOD1 spinal cord showed specific reductions in mitochondrial complex IV subunits consistent with an isolated COX deficiency, while no such reductions were detected in CCS/G86R or CCS/L126Z SOD1 mice. CCS over-expression increased the ratio of reduced to oxidized SOD1 monomers in the spinal cords of G37R SOD1 as well as G93A SOD1 mice, but did not influence the redox state of G86R or L126Z SOD1 monomers. The effects of CCS on disease are SOD1 mutation dependent and correlate with SOD1 redox susceptibility.

Reduction of age-associated pathology in old mice by overexpression of catalase in mitochondria.

Science.gov (United States)

Treuting, Piper M; Linford, Nancy J; Knoblaugh, Sue E; Emond, M J; Morton, John F; Martin, George M; Rabinovitch, Peter S; Ladiges, Warren C

2008-08-01

We describe the effects of mitochondrially targeted catalase (MCAT) expression on end-of-life pathology in mice using detailed semiquantitative histopathological evaluation. We previously reported that the median and maximum life spans of MCAT mice were extended relative to those of wild-type littermates. We now report that MCAT expression is associated with reduced malignant nonhematopoietic tumor burden, reduced cardiac lesions, and a trend toward reduced systemic inflammation, with no effect on hematopoietic neoplasia or glomerulonephropathy. Combined disease burden and comorbidity are also reduced, and MCAT expression is not associated with any detrimental clinical effects. The results suggest that oxidative damage is involved in aging of C57BL/6J mice via modulation of a subset of age-associated lesions. Antioxidant interventions targeting mitochondria may therefore be a viable strategy for prevention or postponement of some age-associated diseases. The variability of the MCAT effect across tissues, however, illustrates the importance of developing semiquantitative histopathology for assessment of comorbidity in life-span studies.

Regenerative hair waves in aging mice and extra-follicular modulators follistatin, dkk1, and sfrp4.

Science.gov (United States)

Chen, Chih-Chiang; Murray, Philip J; Jiang, Ting Xin; Plikus, Maksim V; Chang, Yun-Ting; Lee, Oscar K; Widelitz, Randall B; Chuong, Cheng-Ming

2014-08-01

Hair cycling is modulated by factors both intrinsic and extrinsic to hair follicles. Cycling defects lead to conditions such as aging-associated alopecia. Recently, we demonstrated that mouse skin exhibits regenerative hair waves, reflecting a coordinated regenerative behavior in follicle populations. Here, we use this model to explore the regenerative behavior of aging mouse skin. Old mice (>18 months) tracked over several months show that with progressing age, hair waves slow down, wave propagation becomes restricted, and hair cycle domains fragment into smaller domains. Transplanting aged donor mouse skin to a young host can restore donor cycling within a 3 mm range of the interface, suggesting that changes are due to extracellular factors. Therefore, hair stem cells in aged skin can be reactivated. Molecular studies show that extra-follicular modulators Bmp2, Dkk1, and Sfrp4 increase in early anagen. Further, we identify follistatin as an extra-follicular modulator, which is highly expressed in late telogen and early anagen. Indeed, follistatin induces hair wave propagation and its level decreases in aging mice. We present an excitable medium model to simulate the cycling behavior in aging mice and illustrate how the interorgan macroenvironment can regulate the aging process by integrating both "activator" and "inhibitor" signals.

Aging increases the susceptibility of hepatic inflammation, liver fibrosis and aging in response to high-fat diet in mice.

Science.gov (United States)

Kim, In Hee; Xu, Jun; Liu, Xiao; Koyama, Yukinori; Ma, Hsiao-Yen; Diggle, Karin; You, Young-Hyun; Schilling, Jan M; Jeste, Dilip; Sharma, Kumar; Brenner, David A; Kisseleva, Tatiana

2016-08-01

We aimed to investigate whether aging increases the susceptibility of hepatic and renal inflammation or fibrosis in response to high-fat diet (HFD) and explore the underlying genetic alterations. Middle (10 months old) and old (20 months old) aged, male C57BL/6N mice were fed either a low-fat diet (4 % fat) or HFD (60 % fat) for 4 months. Young (3 months old) aged mice were included as control group. HFD-induced liver and kidney injuries were analyzed by serum and urine assay, histologic staining, immunohistochemistry, and reverse-transcription real-time quantitative polymerase chain reaction. Total RNA sequencing with next-generation technology was done with RNA extracted from liver tissues. With HFD feeding, aged was associated with higher serum alanine aminotransferase levels, marked infiltration of hepatic macrophages, and increased expression of inflammatory cytokines (MCP1, TNF-α, IL-1β, IL-6, IL-12, IL-17A). Importantly, aged mice showed more advanced hepatic fibrosis and increased expression of fibrogenic markers (Col-I-α1, αSMA, TGF-β1, TGF-β2, TGFβRII, PDGF, PDGFRβII, TIMP1) in response to HFD. Aged mice fed on HFD also showed increased oxidative stress and TLR4 expression. In the total RNA seq and gene ontology analysis of liver, old-aged HFD group showed significant up-regulation of genes linked to innate immune response, immune response, defense response, inflammatory response compared to middle-aged HFD group. Meanwhile, aging and HFD feeding showed significant increase in glomerular size and mesangial area, higher urine albumin/creatinine ratio, and advanced renal inflammation or fibrosis. However, the difference of HFD-induced renal injury between old-aged group and middle-aged group was not significant. The susceptibility of hepatic fibrosis as well as hepatic inflammation in response to HFD was significantly increased with aging. In addition, aging was associated with glomerular alterations and increased renal inflammation or

Voluntary wheel running reverses age-induced changes in hippocampal gene expression.

Directory of Open Access Journals (Sweden)

Rachel A Kohman

Full Text Available Normal aging alters expression of numerous genes within the brain. Some of these transcription changes likely contribute to age-associated cognitive decline, reduced neural plasticity, and the higher incidence of neuropathology. Identifying factors that modulate brain aging is crucial for improving quality of life. One promising intervention to counteract negative effects of aging is aerobic exercise. Aged subjects that exercise show enhanced cognitive performance and increased hippocampal neurogenesis and synaptic plasticity. Currently, the mechanisms behind the anti-aging effects of exercise are not understood. The present study conducted a microarray on whole hippocampal samples from adult (3.5-month-old and aged (18-month-old male BALB/c mice that were individually housed with or without running wheels for 8 weeks. Results showed that aging altered genes related to chromatin remodeling, cell growth, immune activity, and synapse organization compared to adult mice. Exercise was found to modulate many of the genes altered by aging, but in the opposite direction. For example, wheel running increased expression of genes related to cell growth and attenuated expression of genes involved in immune function and chromatin remodeling. Collectively, findings show that even late-onset exercise may attenuate age-related changes in gene expression and identifies possible pathways through which exercise may exert its beneficial effects.

Sustained expression of GLP-1 receptor differentially modulates β-cell functions in diabetic and nondiabetic mice

International Nuclear Information System (INIS)

Kubo, Fumiyo; Miyatsuka, Takeshi; Sasaki, Shugo; Takahara, Mitsuyoshi; Yamamoto, Yuichi; Shimo, Naoki; Watada, Hirotaka; Kaneto, Hideaki; Gannon, Maureen; Matsuoka, Taka-aki; Shimomura, Iichiro

2016-01-01

Glucagon-like peptide 1 (GLP-1) has been shown to play important roles in maintaining β-cell functions, such as insulin secretion and proliferation. While expression levels of GLP-1 receptor (Glp1r) are compromised in the islets of diabetic rodents, it remains unclear when and to what degree Glp1r mRNA levels are decreased during the progression of diabetes. In this study, we performed real-time PCR with the islets of db/db diabetic mice at different ages, and found that the expression levels of Glp1r were comparable to those of the islets of nondiabetic db/misty controls at the age of four weeks, and were significantly decreased at the age of eight and 12 weeks. To investigate whether restored expression of Glp1r affects the diabetic phenotypes, we generated the transgenic mouse model Pdx1"P"B-CreER"T"M; CAG-CAT-Glp1r (βGlp1r) that allows for induction of Glp1r expression specifically in β cells. Whereas the expression of exogenous Glp1r had no measurable effect on glucose tolerance in nondiabetic βGlp1r;db/misty mice, βGlp1r;db/db mice exhibited higher glucose and lower insulin levels in blood on glucose challenge test than control db/db littermates. In contrast, four weeks of treatment with exendin-4 improved the glucose profiles and increased serum insulin levels in βGlp1r;db/db mice, to significantly higher levels than those in control db/db mice. These differential effects of exogenous Glp1r in nondiabetic and diabetic mice suggest that downregulation of Glp1r might be required to slow the progression of β-cell failure under diabetic conditions. - Highlights: • Expression levels of incretin receptors were significantly decreased in diabetic db/db islets after the age of eight weeks. • A transgenic mouse model expressing Glp1r specifically in β cells was generated. • Exogenous expression of Glp1r in β cells did not affect metabolic profiles in nondiabetic mice. • Sustained expression of Glp1r in diabetic db/db β cells deteriorated glucose

Sustained expression of GLP-1 receptor differentially modulates β-cell functions in diabetic and nondiabetic mice

Energy Technology Data Exchange (ETDEWEB)

Kubo, Fumiyo [Department of Metabolic Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Miyatsuka, Takeshi, E-mail: miyatsuka-takeshi@umin.net [Department of Metabolic Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Sasaki, Shugo; Takahara, Mitsuyoshi; Yamamoto, Yuichi; Shimo, Naoki [Department of Metabolic Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Watada, Hirotaka [Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Kaneto, Hideaki [Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki, Japan Okayama 701-0192 (Japan); Gannon, Maureen [Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, 2220 Pierce Ave. 746 PRB, Nashville, TN 37232-6303 (United States); Matsuoka, Taka-aki; Shimomura, Iichiro [Department of Metabolic Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

2016-02-26

Glucagon-like peptide 1 (GLP-1) has been shown to play important roles in maintaining β-cell functions, such as insulin secretion and proliferation. While expression levels of GLP-1 receptor (Glp1r) are compromised in the islets of diabetic rodents, it remains unclear when and to what degree Glp1r mRNA levels are decreased during the progression of diabetes. In this study, we performed real-time PCR with the islets of db/db diabetic mice at different ages, and found that the expression levels of Glp1r were comparable to those of the islets of nondiabetic db/misty controls at the age of four weeks, and were significantly decreased at the age of eight and 12 weeks. To investigate whether restored expression of Glp1r affects the diabetic phenotypes, we generated the transgenic mouse model Pdx1{sup PB}-CreER{sup TM}; CAG-CAT-Glp1r (βGlp1r) that allows for induction of Glp1r expression specifically in β cells. Whereas the expression of exogenous Glp1r had no measurable effect on glucose tolerance in nondiabetic βGlp1r;db/misty mice, βGlp1r;db/db mice exhibited higher glucose and lower insulin levels in blood on glucose challenge test than control db/db littermates. In contrast, four weeks of treatment with exendin-4 improved the glucose profiles and increased serum insulin levels in βGlp1r;db/db mice, to significantly higher levels than those in control db/db mice. These differential effects of exogenous Glp1r in nondiabetic and diabetic mice suggest that downregulation of Glp1r might be required to slow the progression of β-cell failure under diabetic conditions. - Highlights: • Expression levels of incretin receptors were significantly decreased in diabetic db/db islets after the age of eight weeks. • A transgenic mouse model expressing Glp1r specifically in β cells was generated. • Exogenous expression of Glp1r in β cells did not affect metabolic profiles in nondiabetic mice. • Sustained expression of Glp1r in diabetic db/db β cells deteriorated

Intestine-specific deletion of microsomal triglyceride transfer protein increases mortality in aged mice.

Science.gov (United States)

Liang, Zhe; Xie, Yan; Dominguez, Jessica A; Breed, Elise R; Yoseph, Benyam P; Burd, Eileen M; Farris, Alton B; Davidson, Nicholas O; Coopersmith, Craig M

2014-01-01

Mice with conditional, intestine-specific deletion of microsomal triglyceride transfer protein (Mttp-IKO) exhibit a complete block in chylomicron assembly together with lipid malabsorption. Young (8-10 week) Mttp-IKO mice have improved survival when subjected to a murine model of Pseudomonas aeruginosa-induced sepsis. However, 80% of deaths in sepsis occur in patients over age 65. The purpose of this study was to determine whether age impacts outcome in Mttp-IKO mice subjected to sepsis. Aged (20-24 months) Mttp-IKO mice and WT mice underwent intratracheal injection with P. aeruginosa. Mice were either sacrificed 24 hours post-operatively for mechanistic studies or followed seven days for survival. In contrast to young septic Mttp-IKO mice, aged septic Mttp-IKO mice had a significantly higher mortality than aged septic WT mice (80% vs. 39%, p = 0.005). Aged septic Mttp-IKO mice exhibited increased gut epithelial apoptosis, increased jejunal Bax/Bcl-2 and Bax/Bcl-XL ratios yet simultaneously demonstrated increased crypt proliferation and villus length. Aged septic Mttp-IKO mice also manifested increased pulmonary myeloperoxidase levels, suggesting increased neutrophil infiltration, as well as decreased systemic TNFα compared to aged septic WT mice. Blocking intestinal chylomicron secretion alters mortality following sepsis in an age-dependent manner. Increases in gut apoptosis and pulmonary neutrophil infiltration, and decreased systemic TNFα represent potential mechanisms for why intestine-specific Mttp deletion is beneficial in young septic mice but harmful in aged mice as each of these parameters are altered differently in young and aged septic WT and Mttp-IKO mice.

Intestine-specific deletion of microsomal triglyceride transfer protein increases mortality in aged mice.

Directory of Open Access Journals (Sweden)

Zhe Liang

Full Text Available Mice with conditional, intestine-specific deletion of microsomal triglyceride transfer protein (Mttp-IKO exhibit a complete block in chylomicron assembly together with lipid malabsorption. Young (8-10 week Mttp-IKO mice have improved survival when subjected to a murine model of Pseudomonas aeruginosa-induced sepsis. However, 80% of deaths in sepsis occur in patients over age 65. The purpose of this study was to determine whether age impacts outcome in Mttp-IKO mice subjected to sepsis.Aged (20-24 months Mttp-IKO mice and WT mice underwent intratracheal injection with P. aeruginosa. Mice were either sacrificed 24 hours post-operatively for mechanistic studies or followed seven days for survival.In contrast to young septic Mttp-IKO mice, aged septic Mttp-IKO mice had a significantly higher mortality than aged septic WT mice (80% vs. 39%, p = 0.005. Aged septic Mttp-IKO mice exhibited increased gut epithelial apoptosis, increased jejunal Bax/Bcl-2 and Bax/Bcl-XL ratios yet simultaneously demonstrated increased crypt proliferation and villus length. Aged septic Mttp-IKO mice also manifested increased pulmonary myeloperoxidase levels, suggesting increased neutrophil infiltration, as well as decreased systemic TNFα compared to aged septic WT mice.Blocking intestinal chylomicron secretion alters mortality following sepsis in an age-dependent manner. Increases in gut apoptosis and pulmonary neutrophil infiltration, and decreased systemic TNFα represent potential mechanisms for why intestine-specific Mttp deletion is beneficial in young septic mice but harmful in aged mice as each of these parameters are altered differently in young and aged septic WT and Mttp-IKO mice.

Ontogeny of SERT Expression and Antidepressant-like Response to Escitalopram in Wild-Type and SERT Mutant Mice.

Science.gov (United States)

Mitchell, Nathan C; Gould, Georgianna G; Koek, Wouter; Daws, Lynette C

2016-08-01

Depression is a disabling affective disorder for which the majority of patients are not effectively treated. This problem is exacerbated in children and adolescents for whom only two antidepressants are approved, both of which are selective serotonin reuptake inhibitor (SSRIs). Unfortunately SSRIs are often less effective in juveniles than in adults; however, the mechanism(s) underlying age-dependent responses to SSRIs is unknown. To this end, we compared the antidepressant-like response to the SSRI escitalopram using the tail suspension test and saturation binding of [(3)H]citalopram to the serotonin transporter (SERT), the primary target of SSRIs, in juvenile [postnatal day (P)21], adolescent (P28), and adult (P90) wild-type (SERT+/+) mice. In addition, to model individuals carrying low-expressing SERT variants, we studied mice with reduced SERT expression (SERT+/-) or lacking SERT (SERT-/-). Maximal antidepressant-like effects were less in P21 mice relative to P90 mice. This was especially apparent in SERT+/- mice. However, the potency for escitalopram to produce antidepressant-like effects in SERT+/+ and SERT+/- mice was greater in P21 and P28 mice than in adults. SERT expression increased with age in terminal regions and decreased with age in cell body regions. Binding affinity values did not change as a function of age or genotype. As expected, in SERT-/- mice escitalopram produced no behavioral effects, and there was no specific [(3)H]citalopram binding. These data reveal age- and genotype-dependent shifts in the dose-response for escitalopram to produce antidepressant-like effects, which vary with SERT expression, and may contribute to the limited therapeutic response to SSRIs in juveniles and adolescents. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Impact of β-hydroxy β-methylbutyrate (HMB) on age-related functional deficits in mice.

Science.gov (United States)

Munroe, Michael; Pincu, Yair; Merritt, Jennifer; Cobert, Adam; Brander, Ryan; Jensen, Tor; Rhodes, Justin; Boppart, Marni D

2017-01-01

β-Hydroxy β-methylbutyrate (HMB) is a metabolite of the essential amino acid leucine. Recent studies demonstrate a decline in plasma HMB concentrations in humans across the lifespan, and HMB supplementation may be able to preserve muscle mass and strength in older adults. However, the impact of HMB supplementation on hippocampal neurogenesis and cognition remains largely unexplored. The purpose of this study was to simultaneously evaluate the impact of HMB on muscle strength, neurogenesis and cognition in young and aged mice. In addition, we evaluated the influence of HMB on muscle-resident mesenchymal stem/stromal cell (Sca-1 + CD45 - ; mMSC) function to address these cells potential to regulate physiological outcomes. Three month-old (n=20) and 24 month-old (n=18) female C57BL/6 mice were provided with either Ca-HMB or Ca-Lactate in a sucrose solution twice per day for 5.5weeks at a dose of 450mg/kg body weight. Significant decreases in relative peak and mean force, balance, and neurogenesis were observed in aged mice compared to young (age main effects, p≤0.05). Short-term HMB supplementation did not alter activity, balance, neurogenesis, or cognitive function in young or aged mice, yet HMB preserved relative peak force in aged mice. mMSC gene expression was significantly reduced with age, but HMB supplementation was able to recover expression of select growth factors known to stimulate muscle repair (HGF, LIF). Overall, our findings demonstrate that while short-term HMB supplementation does not appear to affect neurogenesis or cognitive function in young or aged mice, HMB may maintain muscle strength in aged mice in a manner dependent on mMSC function. Copyright © 2016 Elsevier Inc. All rights reserved.

Pax6 interacts with Iba1 and shows age-associated alterations in brain of aging mice.

Science.gov (United States)

Maurya, Shashank Kumar; Mishra, Rajnikant

2017-07-01

The Pax6, a transcriptional regulator and multifunctional protein, has been found critical for neurogenesis, neuro-degeneration, mental retardation, neuroendocrine tumors, glioblastoma and astrocytomas. The age-associated alteration in the expression of Pax6 in neuron and glia has also been observed in the immunologically privileged brain. Therefore, it is presumed that Pax6 may modulate brain immunity by activation of microglia either directly interacting with genes or proteins of microglia or indirectly though inflammation associated with neurodegeneration. This report describes evaluation of expression, co-localization and interactions of Pax6 with Ionized binding protein1 (Iba1) in brain of aging mice by Immunohistochemistry, Chromatin Immuno-precipitation (ChIP) and Co-immunoprecipitation (Co-IP), respectively. The co-localization of Pax6 with Iba1 was observed in the cerebellum, cerebral cortex, hippocampus, midbrain and olfactory lobe. The Pax6 and Iba1 also interact physically. The age-dependent alteration in their expression and co-localization were also observed in mice. Results indicate Pax6-dependent activities of Iba1 in the remodelling of microglia during immunological surveillance of the brain. Copyright © 2017 Elsevier B.V. All rights reserved.

Astrocytic β2 Adrenergic Receptor Gene Deletion Affects Memory in Aged Mice.

Directory of Open Access Journals (Sweden)

Cathy Joanna Jensen

Full Text Available In vitro and in vivo studies suggest that the astrocytic adrenergic signalling enhances glycogenolysis which provides energy to be transported to nearby cells and in the form of lactate. This energy source is important for motor and cognitive functioning. While it is suspected that the β2-adrenergic receptor on astrocytes might contribute to this energy balance, it has not yet been shown conclusively in vivo. Inducible astrocyte specific β2-adrenergic receptor knock-out mice were generated by crossing homozygous β2-adrenergic receptor floxed mice (Adrb2flox and mice with heterozygous tamoxifen-inducible Cre recombinase-expression driven by the astrocyte specific L-glutamate/L-aspartate transporter promoter (GLAST-CreERT2. Assessments using the modified SHIRPA (SmithKline/Harwell/Imperial College/Royal Hospital/Phenotype Assessment test battery, swimming ability test, and accelerating rotarod test, performed at 1, 2 and 4 weeks, 6 and 12 months after tamoxifen (or vehicle administration did not reveal any differences in physical health or motor functions between the knock-out mice and controls. However deficits were found in the cognitive ability of aged, but not young adult mice, reflected in impaired learning in the Morris Water Maze. Similarly, long-term potentiation (LTP was impaired in hippocampal brain slices of aged knock-out mice maintained in low glucose media. Using microdialysis in cerebellar white matter we found no significant differences in extracellular lactate or glucose between the young adult knock-out mice and controls, although trends were detected. Our results suggest that β2-adrenergic receptor expression on astrocytes in mice may be important for maintaining cognitive health at advanced age, but is dispensable for motor function.

Increased liver pathology in hepatitis C virus transgenic mice expressing the hepatitis B virus X protein

International Nuclear Information System (INIS)

Keasler, Victor V.; Lerat, Herve; Madden, Charles R.; Finegold, Milton J.; McGarvey, Michael J.; Mohammed, Essam M.A.; Forbes, Stuart J.; Lemon, Stanley M.; Hadsell, Darryl L.; Grona, Shala J.; Hollinger, F. Blaine; Slagle, Betty L.

2006-01-01

Transgenic mice expressing the full-length HCV coding sequence were crossed with mice that express the HBV X gene-encoded regulatory protein HBx (ATX mice) to test the hypothesis that HBx expression accelerates HCV-induced liver pathogenesis. At 16 months (mo) of age, hepatocellular carcinoma was identified in 21% of HCV/ATX mice, but in none of the single transgenic animals. Analysis of 8-mo animals revealed that, relative to HCV/WT mice, HCV/ATX mice had more severe steatosis, greater liver-to-body weight ratios, and a significant increase in the percentage of hepatocytes staining for proliferating cell nuclear antigen. Furthermore, primary hepatocytes from HCV, ATX, and HCV/ATX transgenic mice were more resistant to fas-mediated apoptosis than hepatocytes from nontransgenic littermates. These results indicate that HBx expression contributes to increased liver pathogenesis in HCV transgenic mice by a mechanism that involves an imbalance in hepatocyte death and regeneration within the context of severe steatosis

Men and mice: Relating their ages.

Science.gov (United States)

Dutta, Sulagna; Sengupta, Pallav

2016-05-01

Since the late 18th century, the murine model has been widely used in biomedical research (about 59% of total animals used) as it is compact, cost-effective, and easily available, conserving almost 99% of human genes and physiologically resembling humans. Despite the similarities, mice have a diminutive lifespan compared to humans. In this study, we found that one human year is equivalent to nine mice days, although this is not the case when comparing the lifespan of mice versus humans taking the entire life at the same time without considering each phase separately. Therefore, the precise correlation of age at every point in their lifespan must be determined. Determining the age relation between mice and humans is necessary for setting up experimental murine models more analogous in age to humans. Thus, more accuracy can be obtained in the research outcome for humans of a specific age group, although current outcomes are based on mice of an approximate age. To fill this gap between approximation and accuracy, this review article is the first to establish a precise relation between mice age and human age, following our previous article, which explained the relation in ages of laboratory rats with humans in detail. Copyright © 2015 Elsevier Inc. All rights reserved.

Short-term Treatment of Daumone Improves Hepatic Inflammation in Aged Mice.

Science.gov (United States)

Park, Jong Hee; Ha, Hunjoo

2015-05-01

Chronic inflammation has been proposed as one of the main molecular mechanisms of aging and age-related diseases. Although evidence in humans is limited, short-term calorie restriction (CR) has been shown to have anti-inflammatory effects in aged experimental animals. We reported on the long-term treatment of daumone, a synthetic pheromone secreted by Caenorhabditis elegans in an energy deficient environment, extends the life-span and attenuates liver injury in aged mice. The present study examined whether late onset short-term treatment of daumone exerts anti-inflammatory effects in the livers of aged mice. Daumone was administered orally at doses of 2 or 20 mg/kg/day for 5 weeks to 24-month-old male C57BL/6J mice. Increased liver macrophage infiltration and gene expression of proinflammatory cytokines in aged mice were significantly attenuated by daumone treatment, suggesting that short-term oral administration of daumone may have hepatoprotective effects. Daumone also dose-dependently suppressed tumor necrosis factor-α (TNF-α)-induced nuclear factor-κB (NF-κB) phosphorylation in HepG2 cells. The present data demonstrated that short-term treatment of daumone has anti-inflammatory effects in aged mouse livers possibly through suppression of NF-κB signaling and suggest that daumone may become a lead compound targeting aging and age-associated diseases.

Identification of Aging-Associated Gene Expression Signatures That Precede Intestinal Tumorigenesis.

Directory of Open Access Journals (Sweden)

Yoshihisa Okuchi

Full Text Available Aging-associated alterations of cellular functions have been implicated in various disorders including cancers. Due to difficulties in identifying aging cells in living tissues, most studies have focused on aging-associated changes in whole tissues or certain cell pools. Thus, it remains unclear what kinds of alterations accumulate in each cell during aging. While analyzing several mouse lines expressing fluorescent proteins (FPs, we found that expression of FPs is gradually silenced in the intestinal epithelium during aging in units of single crypt composed of clonal stem cell progeny. The cells with low FP expression retained the wild-type Apc allele and the tissues composed of them did not exhibit any histological abnormality. Notably, the silencing of FPs was also observed in intestinal adenomas and the surrounding normal mucosae of Apc-mutant mice, and mediated by DNA methylation of the upstream promoter. Our genome-wide analysis then showed that the silencing of FPs reflects specific gene expression alterations during aging, and that these alterations occur in not only mouse adenomas but also human sporadic and hereditary (familial adenomatous polyposis adenomas. Importantly, pharmacological inhibition of DNA methylation, which suppresses adenoma development in Apc-mutant mice, reverted the aging-associated silencing of FPs and gene expression alterations. These results identify aging-associated gene expression signatures that are heterogeneously induced by DNA methylation and precede intestinal tumorigenesis triggered by Apc inactivation, and suggest that pharmacological inhibition of the signature genes could be a novel strategy for the prevention and treatment of intestinal tumors.

A time-course study of long term over-expression of ARR19 in mice

Science.gov (United States)

Qamar, Imteyaz; Ahmad, Mohammad Faiz; Narayanasamy, Arul

2015-01-01

A leucine-rich protein, ARR19 (androgen receptor corepressor-19 kDa), is highly expressed in male reproductive organs and moderately in others. Previously, we have reported that ARR19 is differentially expressed in adult Leydig cells during the testis development and inhibits steroidogenesis by reducing the expression of steroidogenic enzymes. Whereas in prostate, ARR19 represses the transcriptional activity of AR (androgen receptor), it is important for male sexual differentiation and maturation in prostate and epididymis, through the recruitment of HDAC4. In this study we show that long term adenovirus mediated overexpression of ARR19 in mice testis has the potential of inhibiting the differentiation of testicular and prostatic cells by reducing the size of testis and prostate but has no effect on the growth of seminal vesicles. Further, it reduces the level of progesterone and testosterone by reducing the steroidogenic enzymes such as 3HSD, P450c17 and StAR. This is the first study reporting a time-course analysis of the implications of long term overexpression of ARR19 in mice testis and its effect on other organs such as prostate and seminal vesicles. Taken together, these results suggest that ARR19 may play an important role in the differentiation of male reproductive organs such as testis and prostate. PMID:26260329

Ultraviolet Radiation–Induced Cataract in Mice: The Effect of Age and the Potential Biochemical Mechanism

Science.gov (United States)

Zhang, Jie; Yan, Hong; Löfgren, Stefan; Tian, Xiaoli; Lou, Marjorie F.

2012-01-01

Purpose. To study the effect of age on the morphologic and biochemical alterations induced by in vivo exposure of ultraviolet radiation (UV). Methods. Young and old C57BL/6 mice were exposed to broadband UVB+UVA and euthanized after 2 days. Another batch of UV-exposed young mice was monitored for changes after 1, 2, 4, and 8 days. Age-matched nonexposed mice served as controls. Lens changes were documented in vivo by slit-lamp biomicroscopy and dark field microscopy photographs ex vivo. Lens homogenates were analyzed for glutathione (GSH) level, and the activities of thioredoxin (Trx), thioltransferase (TTase), and glyceraldehyde-3-phosphate dehydrogenase (G3PD). Glutathionylated lens proteins (PSSGs) were detected by immunoblotting using GSH antibody. Western blot analysis was also done for the expression levels of TTase and Trx. Results. Both age groups developed epithelial and superficial anterior subcapsular cataract at 2 days postexposure. The lens GSH level and G3PD activity were decreased, and PSSGs were elevated in both age groups, but more prominent in the older mice. TTase and Trx activity and protein expression were elevated only in the young mice. Interestingly, lens TTase and Trx in the young mice showed a transient increase, peaking at 2 days after UV exposure and returning to baseline at day 8, corroborated by lens transparency. Conclusions. The lenses of old mice were more susceptible to UV radiation–induced cataract. The upregulated TTase and Trx likely provided oxidation damage repair in the young mice. PMID:23010639

Tooth loss early in life suppresses neurogenesis and synaptophysin expression in the hippocampus and impairs learning in mice.

Science.gov (United States)

Kubo, Kin-Ya; Murabayashi, Chika; Kotachi, Mika; Suzuki, Ayumi; Mori, Daisuke; Sato, Yuichi; Onozuka, Minoru; Azuma, Kagaku; Iinuma, Mitsuo

2017-02-01

Tooth loss induced neurological alterations through activation of a stress hormone, corticosterone. Age-related hippocampal morphological and functional changes were accelerated by early tooth loss in senescence-accelerated mouse prone 8 (SAMP8). In order to explore the mechanism underlying the impaired hippocampal function resulting from early masticatory dysfunction due to tooth loss, we investigated the effects of early tooth loss on plasma corticosterone levels, learning ability, neurogenesis, and synaptophysin expression in the hippocampus later in life of SAMP8 mice. We examined the effects of tooth loss soon after tooth eruption (1 month of age) on plasma corticosterone levels, learning ability in the Morris water maze, newborn cell proliferation, survival and differentiation in the hippocampal dentate gyrus, and synaptophysin expression in the hippocampus of aged (8 months of age) SAMP8 mice. Aged mice with early tooth loss exhibited increased plasma corticosterone levels, hippocampus-dependent learning deficits in the Morris water maze, decreased cell proliferation, and cell survival in the dentate gyrus, and suppressed synaptophysin expression in the hippocampus. Newborn cell differentiation in the hippocampal dentate gyrus, however, was not affected by early tooth loss. These findings suggest that learning deficits in aged SAMP8 mice with tooth loss soon after tooth eruption are associated with suppressed neurogenesis and decreased synaptophysin expression resulting from increased plasma corticosterone levels, and that long-term tooth loss leads to impaired cognitive function in older age. Copyright © 2016. Published by Elsevier Ltd.

The effect of aging on efferent nerve fibers regeneration in mice.

Science.gov (United States)

Verdú, E; Butí, M; Navarro, X

1995-10-23

This study evaluates the influence of aging on nerve regeneration and reinnervation of target organs in mice aged 2, 6, 9, 12, 18 and 24 months. In animals of each age group the sciatic nerve was subjected to crush, section or section and suture. Reinnervation of plantar muscles and sweat glands (SG) was evaluated over three months after operation by functional methods. Reappearance of SG secretion and motor responses occurred slightly earlier in young than older mice. The degree of motor and sudomotor reinnervation, with respect to preoperative control values, was also significantly higher in young than old animals. The differences were more pronounced after 12 months of age. The degree of recovery progressively decreased with the severity of the lesion, differences being more marked in older mice. Neurorraphy improved recovery, comparatively more in older than in young mice. These results indicate that, after injuries of peripheral nerves, axonal regeneration and reinnervation are maintained throughout life, but tend to be more delayed and slightly less effective with aging.

Microarray Analysis of Iris Gene Expression in Mice with Mutations Influencing Pigmentation

Science.gov (United States)

Trantow, Colleen M.; Cuffy, Tryphena L.; Fingert, John H.; Kuehn, Markus H.

2011-01-01

Purpose. Several ocular diseases involve the iris, notably including oculocutaneous albinism, pigment dispersion syndrome, and exfoliation syndrome. To screen for candidate genes that may contribute to the pathogenesis of these diseases, genome-wide iris gene expression patterns were comparatively analyzed from mouse models of these conditions. Methods. Iris samples from albino mice with a Tyr mutation, pigment dispersion–prone mice with Tyrp1 and Gpnmb mutations, and mice resembling exfoliation syndrome with a Lyst mutation were compared with samples from wild-type mice. All mice were strain (C57BL/6J), age (60 days old), and sex (female) matched. Microarrays were used to compare transcriptional profiles, and differentially expressed transcripts were described by functional annotation clustering using DAVID Bioinformatics Resources. Quantitative real-time PCR was performed to validate a subset of identified changes. Results. Compared with wild-type C57BL/6J mice, each disease context exhibited a large number of statistically significant changes in gene expression, including 685 transcripts differentially expressed in albino irides, 403 in pigment dispersion–prone irides, and 460 in exfoliative-like irides. Conclusions. Functional annotation clusterings were particularly striking among the overrepresented genes, with albino and pigment dispersion–prone irides both exhibiting overall evidence of crystallin-mediated stress responses. Exfoliative-like irides from mice with a Lyst mutation showed overall evidence of involvement of genes that influence immune system processes, lytic vacuoles, and lysosomes. These findings have several biologically relevant implications, particularly with respect to secondary forms of glaucoma, and represent a useful resource as a hypothesis-generating dataset. PMID:20739468

Treadmill Exercise Attenuates Retinal Oxidative Stress in Naturally-Aged Mice: An Immunohistochemical Study

Directory of Open Access Journals (Sweden)

Chan-Sik Kim

2015-09-01

Full Text Available In the retina, a number of degenerative diseases, including glaucoma, diabetic retinopathy, and age-related macular degeneration, may occur as a result of aging. Oxidative damage is believed to contribute to the pathogenesis of aging as well as to age-related retinal disease. Although physiological exercise has been shown to reduce oxidative stress in rats and mice, it is not known whether it has a similar effect in retinal tissues. The aim of this study was to evaluate retinal oxidative stress in naturally-aged mice. In addition, we evaluated the effects of aerobic training on retinal oxidative stress by immunohistochemically evaluating oxidative stress markers. A group of twelve-week-old male mice were not exercised (young control. Two groups of twenty-two-month-old male mice were created: an old control group and a treadmill exercise group. The old control group mice were not exercised. The treadmill exercise group mice ran on a treadmill (5 to 12 m/min, 30 to 60 min/day, 3 days/week for 12 weeks. The retinal thickness and number of cells in the ganglion cell layer of the naturally-aged mice were reduced compared to those in the young control mice. However, treadmill exercise reversed these morphological changes in the retinas. We evaluated retinal expression of carboxymethyllysine (CML, 8-hydroxy-2′-deoxyguanosine (8-OHdG and nitrotyrosine. The retinas from the aged mice showed increased CML, 8-OHdG, and nitrotyrosine immunostaining intensities compared to young control mice. The exercise group exhibited significantly lower CML levels and nitro-oxidative stress than the old control group. These results suggest that regular exercise can reduce retinal oxidative stress and that physiological exercise may be distinctly advantageous in reducing retinal oxidative stress.

Chronic exercise reduces hypothalamic transforming growth factor-β1 in middle-aged obese mice.

Science.gov (United States)

Silva, Vagner R R; Katashima, Carlos K; Lenhare, Luciene; Silva, Carla G B; Morari, Joseane; Camargo, Rafael L; Velloso, Licio A; Saad, Mario A; da Silva, Adelino S R; Pauli, Jose Rodrigo; Ropelle, Eduardo Rochete

2017-08-28

Obesity and aging are associated with hypothalamic inflammation, hyperphagia and abnormalities in the thermogenesis control. It has been demonstrated that the association between aging and obesity induces hypothalamic inflammation and metabolic disorders, at least in part, through the atypical hypothalamic transforming growth factor-β (TGF-β1). Physical exercise has been used to modulate several metabolic parameters. Thus, the aim of this study was to evaluate the impact of chronic exercise on TGF-β1 expression in the hypothalamus of Middle-Aged mice submitted to a one year of high-fat diet (HFD) treatment. We observed that long-term of HFD-feeding induced hypothalamic TGF-β1 accumulation, potentiated the hypothalamic inflammation, body weight gain and defective thermogenesis of Middle-Aged mice when compared to Middle-Aged animals fed on chow diet. As expected, chronic exercise induced negative energy balance, reduced food consumption and increasing the energy expenditure, which promotes body weight loss. Interestingly, exercise training reduced the TGF-β1 expression and IkB-α ser32 phosphorylation in the hypothalamus of Middle-Aged obese mice. Taken together our study demonstrated that chronic exercise suppressed the TGF-β1/IkB-α axis in the hypothalamus and improved the energy homeostasis in an animal model of obesity-associated to aging.

Muscle Structure Influences Utrophin Expression in mdx Mice

Science.gov (United States)

Banks, Glen B.; Combs, Ariana C.; Odom, Guy L.; Bloch, Robert J.; Chamberlain, Jeffrey S.

2014-01-01

Duchenne muscular dystrophy (DMD) is a severe muscle wasting disorder caused by mutations in the dystrophin gene. To examine the influence of muscle structure on the pathogenesis of DMD we generated mdx4cv:desmin double knockout (dko) mice. The dko male mice died of apparent cardiorespiratory failure at a median age of 76 days compared to 609 days for the desmin−/− mice. An ∼2.5 fold increase in utrophin expression in the dko skeletal muscles prevented necrosis in ∼91% of 1a, 2a and 2d/x fiber-types. In contrast, utrophin expression was reduced in the extrasynaptic sarcolemma of the dko fast 2b fibers leading to increased membrane fragility and dystrophic pathology. Despite lacking extrasynaptic utrophin, the dko fast 2b fibers were less dystrophic than the mdx4cv fast 2b fibers suggesting utrophin-independent mechanisms were also contributing to the reduced dystrophic pathology. We found no overt change in the regenerative capacity of muscle stem cells when comparing the wild-type, desmin−/−, mdx4cv and dko gastrocnemius muscles injured with notexin. Utrophin could form costameric striations with α-sarcomeric actin in the dko to maintain the integrity of the membrane, but the lack of restoration of the NODS (nNOS, α-dystrobrevin 1 and 2, α1-syntrophin) complex and desmin coincided with profound changes to the sarcomere alignment in the diaphragm, deposition of collagen between the myofibers, and impaired diaphragm function. We conclude that the dko mice may provide new insights into the structural mechanisms that influence endogenous utrophin expression that are pertinent for developing a therapy for DMD. PMID:24922526

Mutation types and aging differently affect revertant fiber expansion in dystrophic mdx and mdx52 mice.

Directory of Open Access Journals (Sweden)

Yusuke Echigoya

Full Text Available Duchenne muscular dystrophy (DMD, one of the most common and lethal genetic disorders, and the mdx mouse myopathies are caused by a lack of dystrophin protein. These dystrophic muscles contain sporadic clusters of dystrophin-expressing revertant fibers (RFs, as detected by immunohistochemistry. RFs are known to arise from muscle precursor cells with spontaneous exon skipping (alternative splicing and clonally expand in size with increasing age through the process of muscle degeneration/regeneration. The expansion of revertant clusters is thought to represent the cumulative history of muscle regeneration and proliferation of such precursor cells. However, the precise mechanisms by which RFs arise and expand are poorly understood. Here, to test the effects of mutation types and aging on RF expansion and muscle regeneration, we examined the number of RFs in mdx mice (containing a nonsense mutation in exon 23 and mdx52 mice (containing deletion mutation of exon 52 with the same C57BL/6 background at 2, 6, 12, and 18months of age. Mdx mice displayed a significantly higher number of RFs compared to mdx52 mice in all age groups, suggesting that revertant fiber expansion largely depends on the type of mutation and/or location in the gene. A significant increase in the expression and clustering levels of RFs was found beginning at 6months of age in mdx mice compared with mdx52 mice. In contrast to the significant expansion of RFs with increasing age, the number of centrally nucleated fibers and embryonic myosin heavy chain-positive fibers (indicative of cumulative and current muscle regeneration, respectively decreased with age in both mouse strains. These results suggest that mutation types and aging differently affect revertant fiber expansion in mdx and mdx52 mice.

Ginseng Berry Extract Supplementation Improves Age-Related Decline of Insulin Signaling in Mice

Directory of Open Access Journals (Sweden)

Eunhui Seo

2015-04-01

Full Text Available The aim of this study was to evaluate the effects of ginseng berry extract on insulin sensitivity and associated molecular mechanisms in aged mice. C57BL/6 mice (15 months old were maintained on a regular diet (CON or a regular diet supplemented with 0.05% ginseng berry extract (GBD for 24 or 32 weeks. GBD-fed mice showed significantly lower serum insulin levels (p = 0.016 and insulin resistance scores (HOMA-IR (p = 0.012, suggesting that GBD improved insulin sensitivity. Pancreatic islet hypertrophy was also ameliorated in GBD-fed mice (p = 0.007. Protein levels of tyrosine phosphorylated insulin receptor substrate (IRS-1 (p = 0.047, and protein kinase B (AKT (p = 0.037, were up-regulated in the muscle of insulin-injected GBD-fed mice compared with CON-fed mice. The expressions of forkhead box protein O1 (FOXO1 (p = 0.036 and peroxisome proliferator-activated receptor gamma (PPARγ (p = 0.032, which are known as aging- and insulin resistance-related genes, were also increased in the muscle of GBD-fed mice. We conclude that ginseng berry extract consumption might increase activation of IRS-1 and AKT, contributing to the improvement of insulin sensitivity in aged mice.

IL-1 receptor-antagonist (IL-1Ra) knockout mice show anxiety-like behavior by aging.

Science.gov (United States)

Wakabayashi, Chisato; Numakawa, Tadahiro; Odaka, Haruki; Ooshima, Yoshiko; Kiyama, Yuji; Manabe, Toshiya; Kunugi, Hiroshi; Iwakura, Yoichiro

2015-07-10

Interleukin 1 (IL-1) plays a critical role in stress responses, and its mRNA is induced in the brain by restraint stress. Previously, we reported that IL-1 receptor antagonist (IL-1Ra) knockout (KO) mice, which lacked IL-1Ra molecules that antagonize the IL-1 receptor, showed anti-depression-like behavior via adrenergic modulation at the age of 8 weeks. Here, we report that IL-1Ra KO mice display an anxiety-like phenotype that is induced spontaneously by aging in the elevated plus-maze (EPM) test. This anxiety-like phenotype was improved by the administration of diazepam. The expression of the anxiety-related molecule glucocorticoid receptor (GR) was significantly reduced in 20-week-old but not in 11-week-old IL-1Ra KO mice compared to wild-type (WT) littermates. The expression of the mineralocorticoid receptor (MR) was not altered between IL-1Ra KO mice and WT littermates at either 11 or 20 weeks old. Analysis of monoamine concentration in the hippocampus revealed that tryptophan, the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), and the dopamine metabolite homovanillic acid (HVA) were significantly increased in 20-week-old IL-1Ra KO mice compared to littermate WT mice. These findings strongly suggest that the anxiety-like behavior observed in older mice was caused by the complicated alteration of monoamine metabolism and/or GR expression in the hippocampus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Psychological stress exposure to aged mice causes abnormal feeding patterns with changes in the bout number.

Science.gov (United States)

Yamada, Chihiro; Mogami, Sachiko; Hattori, Tomohisa

2017-11-09

Stress responses are affected by aging. However, studies on stress-related changes in feeding patterns with aging subject are minimal. We investigated feeding patterns induced by two psychological stress models, revealing characteristics of stress-induced feeding patterns as "meal" and "bout" (defined as the minimum feeding behavior parameters) in aged mice. Feeding behaviors of C57BL/6J mice were monitored for 24 h by an automatic monitoring device. Novelty stress reduced the meal amount over the 24 h in both young and aged mice, but as a result of a time course study it was persistent in aged mice. In addition, the decreased bout number was more pronounced in aged mice than in young mice. The 24-h meal and bout parameters did not change in either the young or aged mice following water avoidance stress (WAS). However, the meal amount and bout number increased in aged mice for 0-6 h after WAS exposure but remained unchanged in young mice. Our findings suggest that changes in bout number may lead to abnormal stress-related feeding patterns and may be one tool for evaluating eating abnormality in aged mice.

SERCA2a gene transfer improves electrocardiographic performance in aged mdx mice

Directory of Open Access Journals (Sweden)

Hajjar Roger

2011-08-01

Full Text Available Abstract Background Cardiomyocyte calcium overloading has been implicated in the pathogenesis of Duchenne muscular dystrophy (DMD heart disease. The cardiac isoform of sarcoplasmic reticulum calcium ATPase (SERCA2a plays a major role in removing cytosolic calcium during heart muscle relaxation. Here, we tested the hypothesis that SERCA2a over-expression may mitigate electrocardiography (ECG abnormalities in old female mdx mice, a murine model of DMD cardiomyopathy. Methods 1 × 1012 viral genome particles/mouse of adeno-associated virus serotype-9 (AAV-9 SERCA2a vector was delivered to 12-m-old female mdx mice (N = 5 via a single bolus tail vein injection. AAV transduction and the ECG profile were examined eight months later. Results The vector genome was detected in the hearts of all AAV-injected mdx mice. Immunofluorescence staining and western blot confirmed SERCA2a over-expression in the mdx heart. Untreated mdx mice showed characteristic tachycardia, PR interval reduction and QT interval prolongation. AAV-9 SERCA2a treatment corrected these ECG abnormalities. Conclusions Our results suggest that AAV SERCA2a therapy may hold great promise in treating dystrophin-deficient heart disease.

Over-Expression of Porcine Myostatin Missense Mutant Leads to A Gender Difference in Skeletal Muscle Growth between Transgenic Male and Female Mice.

Science.gov (United States)

Ma, Dezun; Gao, Pengfei; Qian, Lili; Wang, Qingqing; Cai, Chunbo; Jiang, Shengwang; Xiao, Gaojun; Cui, Wentao

2015-08-24

Myostatin, a transforming growth factor-β family member, is a negative regulator of skeletal muscle development and growth. Piedmontese cattle breeds have a missense mutation, which results in a cysteine to tyrosine substitution in the mature myostatin protein (C313Y). This loss-of-function mutation in myostatin results in a double-muscled phenotype in cattle. Myostatin propeptide is an inhibitor of myostatin activity and is considered a potential agent to stimulate muscle growth in livestock. In this study, we generated transgenic mice overexpressing porcine myostatin missense mutant (pmMS), C313Y, and wild-type porcine myostatin propeptide (ppMS), respectively, to examine their effects on muscle growth in mice. Enhanced muscle growth was observed in both pmMS and ppMS transgenic female mice and also in ppMS transgenic male mice. However, there was no enhanced muscle growth observed in pmMS transgenic male mice. To explore why there is such a big difference in muscle growth between pmMS and ppMS transgenic male mice, the expression level of androgen receptor (AR) mutant AR45 was measured by Western blot. Results indicated that AR45 expression significantly increased in pmMS transgenic male mice while it decreased dramatically in ppMS transgenic male mice. Our data demonstrate that both pmMS and ppMS act as myostatin inhibitors in the regulation of muscle growth, but the effect of pmMS in male mice is reversed by an increased AR45 expression. These results provide useful insight and basic theory to future studies on improving pork quality by genetically manipulating myostatin expression or by regulating myostatin activity.

Behavioral responses to and brain distribution of morphine in mature adult and aged mice

International Nuclear Information System (INIS)

Burton, C.K.; Ho, I.K.; Hoskins, B.

1986-01-01

Mature adult (3-6 mo old) and aged (2 yr old) male ICR mice were injected with 10 to 100 mg/kg morphine, s.c. The ED50 values for running behavior (as measured using Stoelting activity monitors and having each mouse serve as its own control) representing 5 times control activity was approximately 7.5 mg/kg for aged mice and approximately 17.5 mg/kg for the mature adults. The ED50 values for analgesia 1 hr after morphine administration using the tail-flick method (max. response time = 8 sec) were approx. 70 mg/kg for the aged mice and 15 mg/kg for the mature adults. One hour after injecting 3 H-morphine at doses of 30 and 100 mg/kg, 0.13 and 0.14% of the doses appeared in brains of aged and mature adult mice, respectively. Regional distribution of the morphine was the same for both age groups. Expressed as percent of total brain morphine, it was as follows: cortex, 30%; midbrain, 18%; cerebellum, 17%; medulla, 12%; pons, 9%; striatum, 8% and periaqueductal gray, 6%. Expressed as g morphine/g tissue for the 2 doses, the distribution was; periaqueductal gray, 30 and 80; striatum, 9 and 34; medulla, 6 and 20 pons; 5 and 19; cerebellum, 4 and 13; midbrain 2.5 and 8.5 and cortex, 2 and 8. These results suggest that the differences in response to morphine by the two age groups were due to age-related differences in opioid receptor populations and/or affinities

Behavioral responses to and brain distribution of morphine in mature adult and aged mice

Energy Technology Data Exchange (ETDEWEB)

Burton, C.K.; Ho, I.K.; Hoskins, B.

1986-03-01

Mature adult (3-6 mo old) and aged (2 yr old) male ICR mice were injected with 10 to 100 mg/kg morphine, s.c. The ED50 values for running behavior (as measured using Stoelting activity monitors and having each mouse serve as its own control) representing 5 times control activity was approximately 7.5 mg/kg for aged mice and approximately 17.5 mg/kg for the mature adults. The ED50 values for analgesia 1 hr after morphine administration using the tail-flick method (max. response time = 8 sec) were approx. 70 mg/kg for the aged mice and 15 mg/kg for the mature adults. One hour after injecting /sup 3/H-morphine at doses of 30 and 100 mg/kg, 0.13 and 0.14% of the doses appeared in brains of aged and mature adult mice, respectively. Regional distribution of the morphine was the same for both age groups. Expressed as percent of total brain morphine, it was as follows: cortex, 30%; midbrain, 18%; cerebellum, 17%; medulla, 12%; pons, 9%; striatum, 8% and periaqueductal gray, 6%. Expressed as g morphine/g tissue for the 2 doses, the distribution was; periaqueductal gray, 30 and 80; striatum, 9 and 34; medulla, 6 and 20 pons; 5 and 19; cerebellum, 4 and 13; midbrain 2.5 and 8.5 and cortex, 2 and 8. These results suggest that the differences in response to morphine by the two age groups were due to age-related differences in opioid receptor populations and/or affinities.

VEGF expression in hepatectomized tumor-bearing mice.

Science.gov (United States)

Andrini, L; Blanco, A Fernandez; Inda, A; García, M; Garcia, A; Errecalde, A

2011-01-01

The experiments were designed in order to study the VEGF expression in intact (group I), hepatectomized (group II), and hepatectomized-tumor bearing mice (group III) throughout one complete circadian time span. Adult male mice were used for the VEGF expression study. The statistical analysis was performed using analysis of variance (ANOVA). The results showed statistical differences in the VEGF expression between groups I and II, but the most significant differences were found between groups I and III. In conclusion, these expressions have a circadian rhythm in all groups; moreover, in group III, this expression was higher and appeared before than in the others.

TREM2 Overexpression has No Improvement on Neuropathology and Cognitive Impairment in Aging APPswe/PS1dE9 Mice.

Science.gov (United States)

Jiang, Teng; Wan, Yu; Zhang, Ying-Dong; Zhou, Jun-Shan; Gao, Qing; Zhu, Xi-Chen; Shi, Jian-Quan; Lu, Huan; Tan, Lan; Yu, Jin-Tai

2017-03-01

Previously, we showed that overexpression of triggering receptor expressed on myeloid cells 2 (TREM2), a microglia-specific immune receptor, in the brain of a middle-aged (7 months old) APPswe/PS1dE9 mice could ameliorate Alzheimer's disease (AD)-related neuropathology by enhancement of microglial amyloid-β (Aβ) phagocytosis. Since AD is an age-related neurodegenerative disorder, it is critical to assess the efficacy of TREM2 overexpression in aging animals with an advanced disease stage. In vivo, we employed a lentiviral strategy to overexpress TREM2 in the brain of aging (18 months old) APPswe/PS1dE9 mice, and observed its efficacy on AD-related neuropathology and cognitive functions. Afterwards, we directly isolated microglia from middle-aged and aging APPswe/PS1dE9 mice and determined effects of TREM2 overexpression on microglial Aβ phagocytosis and Aβ-binding receptors expression in vitro. In aging APPswe/PS1dE9 mice, TREM2 overexpression has no beneficial effect on AD-related neuropathology and spatial cognitive functions. Of note, in vitro experiments showed a significant reduction of Aβ phagocytosis in microglia from aging APPswe/PS1dE9 mice, possibly attributing to the declined expression of Aβ-binding receptors. Meanwhile, this phagocytic deficit in microglia from aging APPswe/PS1dE9 mice cannot be rescued by TREM2 overexpression. Taken together, our study shows that TREM2 overexpression fails to provide neuroprotection in aging APPswe/PS1dE9 mice, possibly attributing to deficits in microglial Aβ phagocytosis at the late-stage of disease progression. These findings indicate that TREM2-mediated protection in AD is at least partially dependent on the reservation of microglial phagocytic functions, emphasizing the importance of early therapeutic interventions for this devastating disease.

Dietary polyphenol supplementation prevents alterations of spatial navigation in middle-aged mice

Directory of Open Access Journals (Sweden)

Julien eBensalem

2016-02-01

Full Text Available Spatial learning and memory deficits associated with hippocampal synaptic plasticity impairments are commonly observed during aging. Besides, the beneficial role of dietary polyphenols has been suggested as potential functional food candidates to prevent this memory decline. Indeed, polyphenols could potentiate the signaling pathways of synaptic plasticity underlying learning and memory. In this study, spatial learning deficits of middle-aged mice were first highlighted and characterized according to navigation patterns in the Morris water maze task. An eight-week polyphenol-enriched diet, containing a polyphenol-rich extract from grape and blueberry (PEGB (from the Neurophenols Consortium with high contents of flavonoids, stilbenes and phenolic acids, was then successful in reversing these age-induced effects. The use of spatial strategies was indeed delayed with aging whereas a polyphenol supplementation could promote the occurrence of spatial strategies. These behavioral results were associated with neurobiological changes: while the expression of hippocampal CaMKII mRNA levels was reduced in middle-aged animals, the polyphenol-enriched diet could rescue them. Besides, an increased expression of NGF mRNA levels was also observed in supplemented adult and middle-aged mice. Thus these data suggest that supplementation with polyphenols could be an efficient nutritional way to prevent age-induced cognitive decline.

Aromatase Expression in the Hippocampus of AD Patients and 5xFAD Mice

Directory of Open Access Journals (Sweden)

Janine Prange-Kiel

2016-01-01

Full Text Available Numerous studies show that 17β-estradiol (E2 protects against Alzheimer’s disease (AD induced neurodegeneration. The E2-synthesizing enzyme aromatase is expressed in healthy hippocampi, but although the hippocampus is severely affected in AD, little is known about the expression of hippocampal aromatase in AD. To better understand the role of hippocampal aromatase in AD, we studied its expression in postmortem material from patients with AD and in a mouse model for AD (5xFAD mice. In human hippocampi, aromatase-immunoreactivity was observed in the vast majority of principal neurons and signal quantification revealed higher expression of aromatase protein in AD patients compared to age- and sex-matched controls. The tissue-specific first exons of aromatase I.f, PII, I.3, and I.6 were detected in hippocampi of controls and AD patients by RT-PCR. In contrast, 3-month-old, female 5xFAD mice showed lower expression of aromatase mRNA and protein (measured by qRT-PCR and semiquantitative immunohistochemistry than WT controls; no such differences were observed in male mice. Our findings stress the importance of hippocampal aromatase expression in neurodegenerative diseases.

Immune response of macrophages from young and aged mice to the oral pathogenic bacterium Porphyromonas gingivalis

Directory of Open Access Journals (Sweden)

Gibson Frank C

2010-11-01

Full Text Available Abstract Periodontal disease is a chronic inflammatory gum disease that in severe cases leads to tooth loss. Porphyromonas gingivalis (Pg is a bacterium closely associated with generalized forms of periodontal disease. Clinical onset of generalized periodontal disease commonly presents in individuals over the age of 40. Little is known regarding the effect of aging on inflammation associated with periodontal disease. In the present study we examined the immune response of bone marrow derived macrophages (BMM from young (2-months and aged (1-year and 2-years mice to Pg strain 381. Pg induced robust expression of cytokines; tumor necrosis factor (TNF-α, interleukin (IL-6, and IL-10, chemokines; neutrophil chemoattractant protein (KC, macrophage colony stimulating factor (MCP-1, macrophage inflammatory protein (MIP-1α and regulated upon activation normal T cell expressed and secreted (RANTES, as well as nitric oxide (NO, measured as nitrite, and prostaglandin E2 (PGE2 from BMM of young mice. BMM from the 2-year age group produced significantly less TNF-α, IL-6 and NO in response to Pg as compared with BMM from 2-months and 1-year of age. We did not observe any difference in the levels of IL-1β, IL-10 and PGE2 produced by BMM in response to Pg. BMM from 2-months and 1-year of age produced similar levels of all chemokines measured with the exception of MCP-1, which was reduced in BMM from 1-year of age. BMM from the 2-year group produced significantly less MCP-1 and MIP-1α compared with 2-months and 1-year age groups. No difference in RANTES production was observed between age groups. Employing a Pg attenuated mutant, deficient in major fimbriae (Pg DPG3, we observed reduced ability of the mutant to stimulate inflammatory mediator expression from BMMs as compared to Pg 381, irrespective of age. Taken together these results support senescence as an important facet of the reduced immunological response observed by BMM of aged host to the

Expression of oxidative phosphorylation components in mitochondria of long-living Ames dwarf mice.

Science.gov (United States)

Brown-Borg, Holly M; Johnson, W Thomas; Rakoczy, Sharlene G

2012-02-01

Reduced signaling of the growth hormone (GH)/insulin-like growth factor-1 (IGF-1) pathway is associated with extended life span in several species. Ames dwarf mice are GH-deficient and live >50% longer than wild-type littermates. Previously, we have shown that tissues from Ames mice exhibit elevated levels of antioxidative enzymes, less H(2)O(2) production, and lower oxidative damage suggesting that mitochondrial function may differ between genotypes. To explore the relationship between hormone deficiency and mitochondria in mice with extended longevity, we evaluated activity, protein, and gene expression of oxidative phosphorylation components in dwarf and wild-type mice at varying ages. Liver complex I + III activity was higher in dwarf mice compared to wild-type mice. The activity of I + III decreased between 3 and 20 months of age in both genotypes with greater declines in wild-type mice in liver and skeletal muscle. Complex IV activities in the kidney were elevated in 3- and 20-month-old dwarf mice relative to wild-type mice. In Ames mice, protein levels of the 39 kDa complex I subunit were elevated at 20 months of age when compared to wild-type mouse mitochondria for every tissue examined. Kidney and liver mitochondria from 20-month-old dwarf mice had elevated levels of both mitochondrially-encoded and nuclear-encoded complex IV proteins compared to wild-type mice (p dwarf mice. Overall, we found that several components of the oxidative phosphorylation (OXPHOS) system were elevated in Ames mice. Mitochondrial to nuclear DNA ratios were not different between genotypes despite the marked increase in PGC-1α levels in dwarf mice. The increased OXPHOS activities, along with lower ROS production in dwarf mice, predict enhanced mitochondrial function and efficiency, two factors likely contributing to long-life in Ames mice.

Testosterone and Dihydrotestosterone Differentially Improve Cognition in Aged Female Mice

Science.gov (United States)

Benice, Ted S.; Raber, Jacob

2009-01-01

Compared with age-matched male mice, female mice experience a more severe age-related cognitive decline (ACD). Since androgens are less abundant in aged female mice compared with aged male mice, androgen supplementation may enhance cognition in aged female mice. To test this, we assessed behavioral performance on a variety of tasks in 22- to…

Toll-like receptor 4 (TLR4) deficient mice are protected from adipose tissue inflammation in aging.

Science.gov (United States)

Ghosh, Amiya K; O'Brien, Martin; Mau, Theresa; Yung, Raymond

2017-09-07

Adipose tissue (AT) inflammation is a central mechanism for metabolic dysfunction in both diet-induced obesity and age-associated obesity. Studies in diet-induced obesity have characterized the role of Fetuin A (Fet A) in Free Fatty Acids (FFA)-mediated TLR4 activation and adipose tissue inflammation. However, the role of Fet A & TLR4 in aging-related adipose tissue inflammation is unknown. In the current study, analysis of epidymymal fat pads of C57/Bl6 male mice, we found that, in contrast to data from diet-induced obesity models, adipose tissue from aged mice have normal Fet A and TLR4 expression. Interestingly, aged TLR4-deficient mice have diminished adipose tissue inflammation compared to normal controls. We further demonstrated that reduced AT inflammation in old TLR4-deficient mice is linked to impaired ER stress, augmented autophagy activity, and diminished senescence phenomenon. Importantly, old TLR4-deficient mice have improved glucose tolerance compared to age-matched wild type mice, suggesting that the observed reduced AT inflammation in aged TLR4-deficient mice has important physiological consequences. Taken together, our present study establishes novel aspect of aging-associated AT inflammation that is distinct from diet-induced AT inflammation. Our results also provide strong evidence that TLR4 plays a significant role in promoting aging adipose tissue inflammation.

Long-Term Exercise Protects against Cellular Stresses in Aged Mice

Directory of Open Access Journals (Sweden)

Irina Belaya

2018-01-01

Full Text Available The current study examined the effect of aging and long-term wheel-running on the expression of heat shock protein (HSP, redox regulation, and endoplasmic reticulum (ER stress markers in tibialis anterior (T.A. and soleus muscle of mice. Male mice were divided into young (Y, 3-month-old, old-sedentary (OS, 24-month-old, and old-exercise (OE, 24-month-old groups. The OE group started voluntary wheel-running at 3 months and continued until 24 months of age. Aging was associated with a higher thioredoxin-interacting protein (TxNiP level, lower thioredoxin-1 (TRX-1 to TxNiP ratio—a determinant of redox regulation and increased CHOP, an indicator of ER stress-related apoptosis signaling in both muscles. Notably, GRP78, a key indicator of ER stress, was selectively elevated in T.A. Long-term exercise decreased TxNiP in T.A. and soleus muscles and increased the TRX-1/TxNiP ratio in soleus muscle of aged mice. Inducible HSP70 and constituent HSC70 were upregulated, whereas CHOP was reduced after exercise in soleus muscle. Thus, our data demonstrated that aging induced oxidative stress and activated ER stress-related apoptosis signaling in skeletal muscle, whereas long-term wheel-running improved redox regulation, ER stress adaptation and attenuated ER stress-related apoptosis signaling. These findings suggest that life-long exercise can protect against age-related cellular stress.

mTOR regulates the expression of DNA damage response enzymes in long-lived Snell dwarf, GHRKO, and PAPPA-KO mice.

Science.gov (United States)

Dominick, Graham; Bowman, Jacqueline; Li, Xinna; Miller, Richard A; Garcia, Gonzalo G

2017-02-01

Studies of the mTOR pathway have prompted speculation that diminished mTOR complex-1 (mTORC1) function may be involved in controlling the aging process. Our previous studies have shown diminished mTORC1 activity in tissues of three long-lived mutant mice: Snell dwarf mice, growth hormone receptor gene disrupted mice (GHRKO), and in this article, mice deficient in the pregnancy-associated protein-A (PAPPA-KO). The ways in which lower mTOR signals slow aging and age-related diseases are, however, not well characterized. Here, we show that Snell, GHKRO, and PAPPA-KO mice express high levels of two proteins involved in DNA repair, O-6-methylguanine-DNA methyltransferase (MGMT) and N-myc downstream-regulated gene 1 (NDRG1). Furthermore, we report that lowering mTOR enhances MGMT and NDRG1 protein expression via post-transcriptional mechanisms. We show that the CCR4-NOT complex, a post-transcriptional regulator of gene expression, is downstream of the mTORC1 pathway and may be responsible for the upregulation of MGMT and NDRG1 in all three varieties of long-lived mice. Our data thus suggest a novel link between DNA repair and mTOR signaling via post-transcriptional regulation involving specific alteration in the CCR4-NOT complex, whose modulation could control multiple aspects of the aging process. © 2016 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Oral treatment with herbal formula B307 alleviates cardiac failure in aging R6/2 mice with Huntington’s disease via suppressing oxidative stress, inflammation, and apoptosis

Directory of Open Access Journals (Sweden)

Lin CL

2015-07-01

Full Text Available Ching-Lung Lin,1 Sheue-Er Wang,2 Chih-Hsiang Hsu,1 Shuenn-Jyi Sheu,3 Chung-Hsin Wu1 1Department of Life Science, National Taiwan Normal University, Taipei, 2Department of Pathological Inspection, Soeurs de Saint Paul de Chartres Medical Corporate Body, Taoyuan City, 3Brion Research Institute of Taiwan, New Taipei City, Taiwan Abstract: Cardiac failure is often observed in aging patients with Huntington’s disease (HD. However, conventional pharmacological treatments for cardiac failure in HD patients have rarely been studied. Chinese herbal medicines, especially combined herbal formulas, have been widely used to treat cardiac dysfunctions over the centuries. Thus, we assess whether oral treatment with herbal formula B307 can alleviate cardiac failure in transgenic mice with HD. After oral B307 or vehicle treatment for 2 weeks, cardiac function and cardiomyocytes in 12-week-old male R6/2 HD mice and their wild-type littermate controls (WT were examined and then compared via echocardiography, immunohistochemistry, and Western blotting. We found that cardiac performance in aging R6/2 HD mice had significantly deteriorated in comparison with their WT (P<0.01. Cardiac expressions of superoxide dismutase 2 (SOD2 and B-cell lymphoma 2 (Bcl-2 in aging R6/2 HD mice were significantly lower than their WT (P<0.01, but cardiac expressions of tumor necrosis factor alpha (TNF-α, neurotrophin-3 (3-NT, 4-hydroxynonenal (4-HNE, Bcl-2-associated X protein (Bax, calpain, caspase 12, caspase 9, and caspase 3 of aging R6/2 HD mice were significantly higher than their WT (P<0.05. Furthermore, we found that cardiac performance in aging R6/2 HD mice had significantly improved under oral B307 treatment (P<0.05. Cardiac expressions of SOD2 and Bcl-2 of aging R6/2 HD mice were significantly higher under oral B307 treatment (P<0.01, but cardiac expressions of TNF-α, 3-NT, 4-HNE, Bax, calpain, caspase 12, caspase 9, and caspase 3 of aging R6/2 HD mice were significantly

Histone deacetylase inhibitors reverse age-related increases in side effects of haloperidol in mice.

Science.gov (United States)

Montalvo-Ortiz, Janitza L; Fisher, Daniel W; Rodríguez, Guadalupe; Fang, Deyu; Csernansky, John G; Dong, Hongxin

2017-08-01

Older patients can be especially susceptible to antipsychotic-induced side effects, and the pharmacodynamic mechanism underlying this phenomenon remains unclear. We hypothesized that age-related epigenetic alterations lead to decreased expression and functionality of the dopamine D2 receptor (D2R), contributing to this susceptibility. In this study, we treated young (2-3 months old) and aged (22-24 months old) C57BL/6 mice with the D2R antagonist haloperidol (HAL) once a day for 14 days to evaluate HAL-induced motor side effects. In addition, we pretreated separate groups of young and aged mice with histone deacetylase (HDAC) inhibitors valproic acid (VPA) or entinostat (MS-275) and then administered HAL. Our results show that the motor side effects of HAL are exaggerated in aged mice as compared to young mice and that HDAC inhibitors are able to reverse the severity of these deficits. HAL-induced motor deficits in aged mice are associated with an age- and drug-dependent decrease in striatal D2R protein levels and functionality. Further, histone acetylation was reduced while histone tri-methylation was increased at specific lysine residues of H3 and H4 within the Drd2 promoter in the striatum of aged mice. HDAC inhibitors, particularly VPA, restored striatal D2R protein levels and functionality and reversed age- and drug-related histone modifications at the Drd2 promoter. These results suggest that epigenetic changes at the striatal Drd2 promoter drive age-related increases in antipsychotic side effect susceptibility, and HDAC inhibitors may be an effective adjunct treatment strategy to reduce side effects in aged populations.

Rejection of large HPV-16 expressing tumors in aged mice by a single immunization of VacciMax® encapsulated CTL/T helper peptides

Directory of Open Access Journals (Sweden)

MacDonald Lisa

2007-06-01

Full Text Available Abstract The incidence of cancer increases significantly in later life, yet few pre-clinical studies of cancer immunotherapy use mice of advanced age. A novel vaccine delivery platform (VacciMax®,VM is described that encapsulates antigens and adjuvants in multilamellar liposomes in a water-in-oil emulsion. The therapeutic potential of VM-based vaccines administered as a single dose was tested in HLA-A2 transgenic mice of advanced age (48–58 weeks old bearing large palpable TC1/A2 tumors. The VM-based vaccines contained one or more peptides having human CTL epitopes derived from HPV 16 E6 and E7. VM formulations contained a single peptide, a mixture of four peptides or the same four peptides linked together in a single long peptide. All VM formulations contained PADRE and CpG as adjuvants and ISA51 as the hydrophobic component of the water-in-oil emulsion. VM-formulated vaccines containing the four peptides as a mixture or linked together in one long peptide eradicated 19-day old established tumors within 21 days of immunization. Peptide-specific cytotoxic cellular responses were confirmed by ELISPOT and intracellular staining for IFN-γ producing CD8+ T cells. Mice rendered tumor-free by vaccination were re-challenged in the opposite flank with 10 million HLF-16 tumor cells, another HLA-A2/E6/E7 expressing tumor cell line. None of these mice developed tumors following the re-challenge. In summary, this report describes a VM-formulated therapeutic vaccine with the following unprecedented outcome: a eradication of large tumors (> 700 mm3 b in mice of advanced age c in less than three weeks post-immunization d following a single vaccination.

Long-term high-level expression of human beta-globin occurs following transplantation of transgenic marrow into irradiated mice.

Science.gov (United States)

Himelstein, A; Ward, M; Podda, S; de la Flor Weiss, E; Costantini, F; Bank, A

1993-03-01

When the human beta-globin gene is transferred into the bone marrow cells of live mice, its expression is very low. To investigate the reason for this, we transferred the bone marrow of transgenic mice containing and expressing the human beta-globin into irradiated recipients. We demonstrate that long-term high level expression of the human beta-globin gene can be maintained in the marrow and blood of irradiated recipients following transplantation. Although expression decreased over time in most animals because of host marrow reconstitution, the ratio of human beta-globin transgene expression to endogenous mouse beta-globin gene expression in donor-derived erythroid cells remained constant over time. We conclude that there is no inherent limitation to efficient expression of an exogenous human beta-globin gene in mouse bone marrow cells following marrow transplantation.

Uncoupling protein-2 mRNA expression in mice subjected to intermittent hypoxia

Directory of Open Access Journals (Sweden)

Luciana Rodrigues Vieira

2015-04-01

Full Text Available Objective: To investigate the effect of intermittent hypoxia-a model of obstructive sleep apnea (OSA-on pancreatic expression of uncoupling protein-2 (UCP2, as well as on glycemic and lipid profiles, in C57BL mice. Methods: For 8 h/day over a 35-day period, male C57BL mice were exposed to intermittent hypoxia (hypoxia group or to a sham procedure (normoxia group. The intermittent hypoxia condition involved exposing mice to an atmosphere of 92% N and 8% CO2 for 30 s, progressively reducing the fraction of inspired oxygen to 8 ± 1%, after which they were exposed to room air for 30 s and the cycle was repeated (480 cycles over the 8-h experimental period. Pancreases were dissected to isolate the islets. Real-time PCR was performed with TaqMan assays. Results: Expression of UCP2 mRNA in pancreatic islets was 20% higher in the normoxia group than in the hypoxia group (p = 0.11. Fasting serum insulin was higher in the hypoxia group than in the normoxia group (p = 0.01. The homeostasis model assessment of insulin resistance indicated that, in comparison with the control mice, the mice exposed to intermittent hypoxia showed 15% lower insulin resistance (p = 0.09 and 21% higher pancreatic β-cell function (p = 0.01. Immunohistochemical staining of the islets showed no significant differences between the two groups in terms of the area or intensity of α- and β-cell staining for insulin and glucagon. Conclusions: To our knowledge, this is the first report of the effect of intermittent hypoxia on UCP2 expression. Our findings suggest that UCP2 regulates insulin production in OSA. Further study of the role that UCP2 plays in the glycemic control of OSA patients is warranted.

Dietary lactoferrin alleviates age-related lacrimal gland dysfunction in mice.

Directory of Open Access Journals (Sweden)

Motoko Kawashima

Full Text Available BACKGROUND: Decrease in lacrimal gland secretory function is related to age-induced dry eye disease. Lactoferrin, the main glycoprotein component of tears, has multiple functions, including anti-inflammatory effects and the promotion of cell growth. We investigated how oral administration of lactoferrin affects age-related lacrimal dysfunction. METHODS AND FINDINGS: Twelve-month-old male C57BL/6Cr Slc mice were randomly divided into a control fed group and an oral lactoferrin treatment group. Tear function was measured at a 6-month time-point. After euthanasia, the lacrimal glands were subjected to histological examination with 8-hydroxy-2'-deoxyguanosine (8-OHdG antibodies, and serum concentrations of 8-OHdG and hexanoyl-lysine adduct (HEL were evaluated. Additionally, monocyte chemotactic protein-1(MCP-1 and tumor necrosis factor-α (TNF-α gene expression levels were determined by real-time PCR. The volume of tear secretion was significantly larger in the treated group than in the control. Lactoferrin administration reduced inflammatory cell infiltration and the MCP-1 and TNF-α expression levels. Serum concentrations of 8-OHdG and HEL in the lactoferrin group were lower than those in the control group and were associated with attenuated 8-OHdG immunostaining of the lacrimal glands. CONCLUSION: Oral lactoferrin administration preserves lacrimal gland function in aged mice by attenuating oxidative damage and suppressing subsequent gland inflammation.

Over-expression of Stat5b confers protection against diabetes in the non-obese diabetic (NOD) mice via up-regulation of CD4+CD25+ regulatory T cells

International Nuclear Information System (INIS)

Jin, Yulan; Purohit, Sharad; Chen, Xueqin; Yi, Bing; She, Jin-Xiong

2012-01-01

Highlights: ► This is the first study to provide direct evidence of the role of Stat5b in NOD mice. ► Over-expression of wild type Stat5b transgene protects NOD mice against diabetes. ► This protection may be mediated by the up-regulation of CD4 + CD25 + Tregs. -- Abstract: The signal transducers and activators of transcription (STAT) family of proteins play a critical role in cytokine signaling required for fine tuning of immune regulation. Previous reports showed that a mutation (L327M) in the Stat5b protein leads to aberrant cytokine signaling in the NOD mice. To further elaborate the role of Stat5b in diabetes, we established a NOD transgenic mouse that over-expresses the wild type Stat5b gene. The incidences of spontaneous diabetes as well as cyclophosphamide-induced diabetes were significantly reduced and delayed in the Stat5b transgenic NOD mice compared to their littermate controls. The total cell numbers of CD4 + T cells and especially CD8 + T cells in the spleen and pancreatic lymph node were increased in the Stat5b transgenic NOD mice. Consistent with these findings, CD4 + and CD8 + T cells from the Stat5b transgenic NOD mice showed a higher proliferation capacity and up-regulation of multiple cytokines including IL-2, IFN-γ, TNF-α and IL-10 as well as anti-apoptotic gene Bcl-xl. Furthermore, the number and proportion of CD4 + CD25 + regulatory T cells were significantly increased in transgenic mice although in vitro suppression ability of the regulatory T-cells was not affected by the transgene. Our results suggest that Stat5b confers protection against diabetes in the NOD mice by regulating the numbers and function of multiple immune cell types, especially by up-regulating CD4 + CD25 + regulatory T cells.

Short-term long chain omega3 diet protects from neuroinflammatory processes and memory impairment in aged mice.

Directory of Open Access Journals (Sweden)

Virginie F Labrousse

Full Text Available Regular consumption of food enriched in omega3 polyunsaturated fatty acids (ω3 PUFAs has been shown to reduce risk of cognitive decline in elderly, and possibly development of Alzheimer's disease. Docosahexaenoic acid (DHA and eicosapentaenoic acid (EPA are the most likely active components of ω3-rich PUFAs diets in the brain. We therefore hypothesized that exposing mice to a DHA and EPA enriched diet may reduce neuroinflammation and protect against memory impairment in aged mice. For this purpose, mice were exposed to a control diet throughout life and were further submitted to a diet enriched in EPA and DHA during 2 additional months. Cytokine expression together with a thorough analysis of astrocytes morphology assessed by a 3D reconstruction was measured in the hippocampus of young (3-month-old and aged (22-month-old mice. In addition, the effects of EPA and DHA on spatial memory and associated Fos activation in the hippocampus were assessed. We showed that a 2-month EPA/DHA treatment increased these long-chain ω3 PUFAs in the brain, prevented cytokines expression and astrocytes morphology changes in the hippocampus and restored spatial memory deficits and Fos-associated activation in the hippocampus of aged mice. Collectively, these data indicated that diet-induced accumulation of EPA and DHA in the brain protects against neuroinflammation and cognitive impairment linked to aging, further reinforcing the idea that increased EPA and DHA intake may provide protection to the brain of aged subjects.

Sirtuin1 Over-Expression Does Not Impact Retinal Vascular and Neuronal Degeneration in a Mouse Model of Oxygen-Induced Retinopathy

Science.gov (United States)

Michan, Shaday; Juan, Aimee M.; Hurst, Christian G.; Cui, Zhenghao; Evans, Lucy P.; Hatton, Colman J.; Pei, Dorothy T.; Ju, Meihua; Sinclair, David A.; Smith, Lois E. H.; Chen, Jing

2014-01-01

Proliferative retinopathy is a leading cause of blindness, including retinopathy of prematurity (ROP) in children and diabetic retinopathy in adults. Retinopathy is characterized by an initial phase of vessel loss, leading to tissue ischemia and hypoxia, followed by sight threatening pathologic neovascularization in the second phase. Previously we found that Sirtuin1 (Sirt1), a metabolically dependent protein deacetylase, regulates vascular regeneration in a mouse model of oxygen-induced proliferative retinopathy (OIR), as neuronal depletion of Sirt1 in retina worsens retinopathy. In this study we assessed whether over-expression of Sirtuin1 in retinal neurons and vessels achieved by crossing Sirt1 over-expressing flox mice with Nestin-Cre mice or Tie2-Cre mice, respectively, may protect against retinopathy. We found that over-expression of Sirt1 in Nestin expressing retinal neurons does not impact vaso-obliteration or pathologic neovascularization in OIR, nor does it influence neuronal degeneration in OIR. Similarly, increased expression of Sirt1 in Tie2 expressing vascular endothelial cells and monocytes/macrophages does not protect retinal vessels in OIR. In addition to the genetic approaches, dietary supplement with Sirt1 activators, resveratrol or SRT1720, were fed to wild type mice with OIR. Neither treatment showed significant vaso-protective effects in retinopathy. Together these results indicate that although endogenous Sirt1 is important as a stress-induced protector in retinopathy, over-expression of Sirt1 or treatment with small molecule activators at the examined doses do not provide additional protection against retinopathy in mice. Further studies are needed to examine in depth whether increasing levels of Sirt1 may serve as a potential therapeutic approach to treat or prevent retinopathy. PMID:24416337

Sirtuin1 over-expression does not impact retinal vascular and neuronal degeneration in a mouse model of oxygen-induced retinopathy.

Science.gov (United States)

Michan, Shaday; Juan, Aimee M; Hurst, Christian G; Cui, Zhenghao; Evans, Lucy P; Hatton, Colman J; Pei, Dorothy T; Ju, Meihua; Sinclair, David A; Smith, Lois E H; Chen, Jing

2014-01-01

Proliferative retinopathy is a leading cause of blindness, including retinopathy of prematurity (ROP) in children and diabetic retinopathy in adults. Retinopathy is characterized by an initial phase of vessel loss, leading to tissue ischemia and hypoxia, followed by sight threatening pathologic neovascularization in the second phase. Previously we found that Sirtuin1 (Sirt1), a metabolically dependent protein deacetylase, regulates vascular regeneration in a mouse model of oxygen-induced proliferative retinopathy (OIR), as neuronal depletion of Sirt1 in retina worsens retinopathy. In this study we assessed whether over-expression of Sirtuin1 in retinal neurons and vessels achieved by crossing Sirt1 over-expressing flox mice with Nestin-Cre mice or Tie2-Cre mice, respectively, may protect against retinopathy. We found that over-expression of Sirt1 in Nestin expressing retinal neurons does not impact vaso-obliteration or pathologic neovascularization in OIR, nor does it influence neuronal degeneration in OIR. Similarly, increased expression of Sirt1 in Tie2 expressing vascular endothelial cells and monocytes/macrophages does not protect retinal vessels in OIR. In addition to the genetic approaches, dietary supplement with Sirt1 activators, resveratrol or SRT1720, were fed to wild type mice with OIR. Neither treatment showed significant vaso-protective effects in retinopathy. Together these results indicate that although endogenous Sirt1 is important as a stress-induced protector in retinopathy, over-expression of Sirt1 or treatment with small molecule activators at the examined doses do not provide additional protection against retinopathy in mice. Further studies are needed to examine in depth whether increasing levels of Sirt1 may serve as a potential therapeutic approach to treat or prevent retinopathy.

Neuropathology in mice expressing mouse alpha-synuclein.

Directory of Open Access Journals (Sweden)

Claus Rieker

Full Text Available α-Synuclein (αSN in human is tightly linked both neuropathologically and genetically to Parkinson's disease (PD and related disorders. Disease-causing properties in vivo of the wildtype mouse ortholog (mαSN, which carries a threonine at position 53 like the A53T human mutant version that is genetically linked to PD, were never reported. To this end we generated mouse lines that express mαSN in central neurons at levels reaching up to six-fold compared to endogenous mαSN. Unlike transgenic mice expressing human wildtype or mutant forms of αSN, these mαSN transgenic mice showed pronounced ubiquitin immunopathology in spinal cord and brainstem. Isoelectric separation of mαSN species revealed multiple isoforms including two Ser129-phosphorylated species in the most severely affected brain regions. Neuronal Ser129-phosphorylated αSN occurred in granular and small fibrillar aggregates and pathological staining patterns in neurites occasionally revealed a striking ladder of small alternating segments staining either for Ser129-phosphorylated αSN or ubiquitin but not both. Axonal degeneration in long white matter tracts of the spinal cord, with breakdown of myelin sheaths and degeneration of neuromuscular junctions with loss of integrity of the presynaptic neurofilament network in mαSN transgenic mice, was similar to what we have reported for mice expressing human αSN wildtype or mutant forms. In hippocampal neurons, the mαSN protein accumulated and was phosphorylated but these neurons showed no ubiquitin immunopathology. In contrast to the early-onset motor abnormalities and muscle weakness observed in mice expressing human αSN, mαSN transgenic mice displayed only end-stage phenotypic alterations that manifested alongside with neuropathology. Altogether these findings show that increased levels of wildtype mαSN does not induce early-onset behavior changes, but drives end-stage pathophysiological changes in murine neurons that are

Influence of Sex and Age on Natural Resistance to St. Louis Encephalitis Virus Infection in Mice

Science.gov (United States)

Andersen, Arthur A.; Hanson, Robert P.

1974-01-01

A difference was observed in susceptibility of adult male and female mice to St. Louis encephalitis (SLE) virus as measured by the death rate after intravenous challenge. Female mice that had susceptibility similar to that of males at 2 months of age had increased resistance to SLE virus at 3 and 4 months of age. The increased resistance occurred after sexual maturity, indicating that the resistance factor possibly was related to an aging process in the female. The susceptibility of male mice remained unchanged over the 2- to 4-month period. Neither pregnancy nor castration had any effect on resistance of adult mice to St. Louis encephalitis virus. PMID:4857422

Aberrant Bone Density in Aging Mice Lacking the Adenosine Transporter ENT1

Science.gov (United States)

Hinton, David J.; McGee-Lawrence, Meghan E.; Lee, Moonnoh R.; Kwong, Hoi K.; Westendorf, Jennifer J.; Choi, Doo-Sup

2014-01-01

Adenosine is known to regulate bone production and resorption in humans and mice. Type 1 equilibrative nucleoside transporter (ENT1) is responsible for the majority of adenosine transport across the plasma membrane and is ubiquitously expressed in both humans and mice. However, the contribution of ENT1-mediated adenosine levels has not been studied in bone remodeling. With the recent identification of the importance of adenosine signaling in bone homeostasis, it is essential to understand the role of ENT1 to develop novel therapeutic compounds for bone disorders. Here we examined the effect of ENT1 deletion on bone density using X-ray, dual energy X-ray absorptiometry and micro-computerized tomography analysis. Our results show that bone density and bone mineral density is reduced in the lower thoracic and lumbar spine as well as the femur of old ENT1 null mice (>7 months) compared to wild-type littermates. Furthermore, we found increased mRNA expression of tartrate-resistant acid phosphatase (TRAP), an osteoclast marker, in isolated long bones from 10 month old ENT1 null mice compared to wild-type mice. In addition, aged ENT1 null mice displayed severe deficit in motor coordination and locomotor activity, which might be attributed to dysregulated bone density. Overall, our study suggests that ENT1-regulated adenosine signaling plays an essential role in lumbar spine and femur bone density. PMID:24586402

Aberrant bone density in aging mice lacking the adenosine transporter ENT1.

Directory of Open Access Journals (Sweden)

David J Hinton

Full Text Available Adenosine is known to regulate bone production and resorption in humans and mice. Type 1 equilibrative nucleoside transporter (ENT1 is responsible for the majority of adenosine transport across the plasma membrane and is ubiquitously expressed in both humans and mice. However, the contribution of ENT1-mediated adenosine levels has not been studied in bone remodeling. With the recent identification of the importance of adenosine signaling in bone homeostasis, it is essential to understand the role of ENT1 to develop novel therapeutic compounds for bone disorders. Here we examined the effect of ENT1 deletion on bone density using X-ray, dual energy X-ray absorptiometry and micro-computerized tomography analysis. Our results show that bone density and bone mineral density is reduced in the lower thoracic and lumbar spine as well as the femur of old ENT1 null mice (>7 months compared to wild-type littermates. Furthermore, we found increased mRNA expression of tartrate-resistant acid phosphatase (TRAP, an osteoclast marker, in isolated long bones from 10 month old ENT1 null mice compared to wild-type mice. In addition, aged ENT1 null mice displayed severe deficit in motor coordination and locomotor activity, which might be attributed to dysregulated bone density. Overall, our study suggests that ENT1-regulated adenosine signaling plays an essential role in lumbar spine and femur bone density.

Age-related retinopathy in NRF2-deficient mice.

Directory of Open Access Journals (Sweden)

Zhenyang Zhao

2011-04-01

Full Text Available Cumulative oxidative damage is implicated in the pathogenesis of age-related macular degeneration (AMD. Nuclear factor erythroid 2-related factor 2 (NRF2 is a transcription factor that plays key roles in retinal antioxidant and detoxification responses. The purposes of this study were to determine whether NRF2-deficient mice would develop AMD-like retinal pathology with aging and to explore the underlying mechanisms.Eyes of both wild type and Nrf2(-/- mice were examined in vivo by fundus photography and electroretinography (ERG. Structural changes of the outer retina in aged animals were examined by light and electron microscopy, and immunofluorescence labeling. Our results showed that Nrf2(-/- mice developed age-dependent degenerative pathology in the retinal pigment epithelium (RPE. Drusen-like deposits, accumulation of lipofuscin, spontaneous choroidal neovascularization (CNV and sub-RPE deposition of inflammatory proteins were present in Nrf2(-/- mice after 12 months. Accumulation of autophagy-related vacuoles and multivesicular bodies was identified by electron microscopy both within the RPE and in Bruch's membrane of aged Nrf2(-/- mice.Our data suggest that disruption of Nfe2l2 gene increased the vulnerability of outer retina to age-related degeneration. NRF2-deficient mice developed ocular pathology similar to cardinal features of human AMD and deregulated autophagy is likely a mechanistic link between oxidative injury and inflammation. The Nrf2(-/- mice can provide a novel model for mechanistic and translational research on AMD.

Ketogenic Diet Reduces Midlife Mortality and Improves Memory in Aging Mice.

Science.gov (United States)

Newman, John C; Covarrubias, Anthony J; Zhao, Minghao; Yu, Xinxing; Gut, Philipp; Ng, Che-Ping; Huang, Yu; Haldar, Saptarsi; Verdin, Eric

2017-09-05

Ketogenic diets recapitulate certain metabolic aspects of dietary restriction such as reliance on fatty acid metabolism and production of ketone bodies. We investigated whether an isoprotein ketogenic diet (KD) might, like dietary restriction, affect longevity and healthspan in C57BL/6 male mice. We find that Cyclic KD, KD alternated weekly with the Control diet to prevent obesity, reduces midlife mortality but does not affect maximum lifespan. A non-ketogenic high-fat diet (HF) fed similarly may have an intermediate effect on mortality. Cyclic KD improves memory performance in old age, while modestly improving composite healthspan measures. Gene expression analysis identifies downregulation of insulin, protein synthesis, and fatty acid synthesis pathways as mechanisms common to KD and HF. However, upregulation of PPARα target genes is unique to KD, consistent across tissues, and preserved in old age. In all, we show that a non-obesogenic ketogenic diet improves survival, memory, and healthspan in aging mice. Published by Elsevier Inc.

Aberrant phenotypes of transgenic mice expressing dimeric human erythropoietin

Directory of Open Access Journals (Sweden)

Yun Seong-Jo

2012-01-01

Full Text Available Abstract Background Dimeric human erythropoietin (dHuEPO peptides are reported to exhibit significantly higher biological activity than the monomeric form of recombinant EPO. The objective of this study was to produce transgenic (tg mice expressing dHuEPO and to investigate the characteristics of these mice. Methods A dHuEPO-expressing vector under the control of the goat beta-casein promoter, which produced a dimer of human EPO molecules linked by a 2-amino acid peptide linker (Asp-Ile, was constructed and injected into 1-cell fertilized embryos by microinjection. Mice were screened using genomic DNA samples obtained from tail biopsies. Blood samples were obtained by heart puncture using heparinized tubes, and hematologic parameters were assessed. Using the microarray analysis tool, we analyzed differences in gene expression in the spleens of tg and control mice. Results A high rate of spontaneous abortion or death of the offspring was observed in the recipients of dHuEPO embryos. We obtained 3 founder lines (#4, #11, and #47 of tg mice expressing the dHuEPO gene. However, only one founder line showed stable germline integration and transmission, subsequently establishing the only transgenic line (#11. We obtained 2 F1 mice and 3 F2 mice from line #11. The dHuEPO protein could not be obtained because of repeated spontaneous abortions in the tg mice. Tg mice exhibited symptoms such as short lifespan and abnormal blood composition. The red blood cell count, white blood cell count, and hematocrit levels in the tg mice were remarkably higher than those in the control mice. The spleens of the tg mice (F1 and F2 females were 11- and -21-fold larger than those of the control mice. Microarray analysis revealed 2,672 spleen-derived candidate genes; more genes were downregulated than upregulated (849/764. Reverse transcriptase-polymerase chain reaction (RT-PCR and quantitative real-time PCR (qRT-PCR were used for validating the results of the microarray

Dwarf Mice and Aging.

Science.gov (United States)

Masternak, Michal M; Darcy, Justin; Victoria, Berta; Bartke, Andrzej

2018-01-01

Dwarf mice have been studied for many decades, however, the focus of these studies shifted in 1996 when it was shown by Brown-Borg and her coworkers that Ames dwarf (Prop1 df ) mice are exceptionally long-lived. Since then, Snell dwarf (Pit1 dw ) and growth hormone receptor knockout (GHR-KO, a.k.a. Laron dwarf) mice were also shown to be exceptionally long-lived, presumably due to their growth hormone (GH)-deficiency or -resistance, respectively. What is of equal importance in these dwarf mice is their extended health span, that is, these animals have a longer period of life lived free of frailty and age-related diseases. This review article focuses on recent studies conducted in these dwarf mice, which concerned brown and white adipose tissue biology, microRNA (miRNA) profiling, as well as early-life dietary and hormonal interventions. Results of these studies identify novel mechanisms linking reduced GH action with extensions of both life span and health span. Copyright © 2017. Published by Elsevier Inc.

Peptide YY induces characteristic meal patterns of aged mice.

Science.gov (United States)

Mogami, Sachiko; Yamada, Chihiro; Fujitsuka, Naoki; Hattori, Tomohisa

2017-11-01

Changes in eating behavior occur in the elderly due to oral and swallowing dysfunctions. We aimed to clarify the difference between basal meal patterns of young and aged mice in relation to appetite regulating hormones. Thirty two of young (7-week-old) and aged (23-25-month-old) C57BL/6 male mice were acclimated to a single housing and then transferred to a highly sensitive automated feeding monitoring device. Feeding behavior was monitored from the onset of the dark phase after habituation to the device. Plasma peptide YY (PYY) levels were assessed under the several feeding status or after treatment of PYY. PYY and its receptor (NPY Y2 receptor, Y2R) antagonist were intraperitoneally administered 30min before the monitoring. Although the basal 24-h meal amounts did not differ by age, the total meal time and frequency of minimum feeding activity (bout) were significantly increased and the average bout size and time per bout were significantly decreased in aged mice. PYY dynamics were abnormal and the temporal reduction in food intake by exogenous PYY was more prominent in aged mice than in young mice. PYY administration to young mice induced aged-like meal patterns, and Y2R antagonist administration to aged mice induced young-like meal patterns. Aged mice exhibited characteristic meal patterns probably due to PYY metabolism dysfunction and/or enhanced PYY-Y2R signaling, suggesting a novel method for assessing eating difficulties in aged animals and a potential target for the remedy. Copyright © 2017 Elsevier Inc. All rights reserved.

Intestinal immunity in hypopituitary dwarf mice: effects of age.

Science.gov (United States)

Wang, Xin; Darcy, Justin; Cai, Chuan; Jin, Junfei; Bartke, Andrzej; Cao, Deliang

2018-03-02

Hypopituitary dwarf mice demonstrate advantages of longevity, but little is known of their colon development and intestinal immunity. Herein we found that Ames dwarf mice have shorter colon and colonic crypts, but larger ratio of mesenteric lymph nodes (MLNs) over body weight than age-matched wild type (WT) mice. In the colonic lamina propria (cLP) of juvenile Ames mice, more inflammatory neutrophils (Ā: 0.15% vs. 0.03% in WT mice) and monocytes (Ā: 7.97% vs. 5.15%) infiltrated, and antigen presenting cells CD11c+ dendritic cells (Ā: 1.39% vs. 0.87%), CD11b+ macrophages (Ā: 3.22% vs. 0.81%) and gamma delta T (γδ T) cells (Ā: 5.56% vs. 1.35%) were increased. In adult Ames dwarf mice, adaptive immune cells, such as IL-17 producing CD4+ T helper (Th17) cells (Ā: 8.3% vs. 4.7%) were augmented. In the MLNs of Ames dwarf mice, the antigen presenting and adaptive immune cells also altered when compared to WT mice, such as a decrease of T-regulatory (Treg) cells in juvenile Ames mice (Ā: 7.7% vs.10.5%), but an increase of Th17 cells (Ā: 0.627% vs.0.093%). Taken together, these data suggest that somatotropic signaling deficiency influences colon development and intestinal immunity.

Macrophage Depletion Ameliorates Peripheral Neuropathy in Aging Mice.

Science.gov (United States)

Yuan, Xidi; Klein, Dennis; Kerscher, Susanne; West, Brian L; Weis, Joachim; Katona, Istvan; Martini, Rudolf

2018-05-09

Aging is known as a major risk factor for the structure and function of the nervous system. There is urgent need to overcome such deleterious effects of age-related neurodegeneration. Here we show that peripheral nerves of 24-month-old aging C57BL/6 mice of either sex show similar pathological alterations as nerves from aging human individuals, whereas 12-month-old adult mice lack such alterations. Specifically, nerve fibers showed demyelination, remyelination and axonal lesion. Moreover, in the aging mice, neuromuscular junctions showed features typical for dying-back neuropathies, as revealed by a decline of presynaptic markers, associated with α-bungarotoxin-positive postsynapses. In line with these observations were reduced muscle strengths. These alterations were accompanied by elevated numbers of endoneurial macrophages, partially comprising the features of phagocytosing macrophages. Comparable profiles of macrophages could be identified in peripheral nerve biopsies of aging persons. To determine the pathological impact of macrophages in aging mice, we selectively targeted the cells by applying an orally administered CSF-1R specific kinase (c-FMS) inhibitor. The 6-month-lasting treatment started before development of degenerative changes at 18 months and reduced macrophage numbers in mice by ∼70%, without side effects. Strikingly, nerve structure was ameliorated and muscle strength preserved. We show, for the first time, that age-related degenerative changes in peripheral nerves are driven by macrophages. These findings may pave the way for treating degeneration in the aging peripheral nervous system by targeting macrophages, leading to reduced weakness, improved mobility, and eventually increased quality of life in the elderly. SIGNIFICANCE STATEMENT Aging is a major risk factor for the structure and function of the nervous system. Here we show that peripheral nerves of 24-month-old aging mice show similar degenerative alterations as nerves from aging

Differential gene expression in ADAM10 and mutant ADAM10 transgenic mice

Directory of Open Access Journals (Sweden)

Postina Rolf

2009-02-01

Full Text Available Abstract Background In a transgenic mouse model of Alzheimer disease (AD, cleavage of the amyloid precursor protein (APP by the α-secretase ADAM10 prevented amyloid plaque formation, and alleviated cognitive deficits. Furthermore, ADAM10 overexpression increased the cortical synaptogenesis. These results suggest that upregulation of ADAM10 in the brain has beneficial effects on AD pathology. Results To assess the influence of ADAM10 on the gene expression profile in the brain, we performed a microarray analysis using RNA isolated from brains of five months old mice overexpressing either the α-secretase ADAM10, or a dominant-negative mutant (dn of this enzyme. As compared to non-transgenic wild-type mice, in ADAM10 transgenic mice 355 genes, and in dnADAM10 mice 143 genes were found to be differentially expressed. A higher number of genes was differentially regulated in double-transgenic mouse strains additionally expressing the human APP[V717I] mutant. Overexpression of proteolytically active ADAM10 affected several physiological pathways, such as cell communication, nervous system development, neuron projection as well as synaptic transmission. Although ADAM10 has been implicated in Notch and β-catenin signaling, no significant changes in the respective target genes were observed in adult ADAM10 transgenic mice. Real-time RT-PCR confirmed a downregulation of genes coding for the inflammation-associated proteins S100a8 and S100a9 induced by moderate ADAM10 overexpression. Overexpression of the dominant-negative form dnADAM10 led to a significant increase in the expression of the fatty acid-binding protein Fabp7, which also has been found in higher amounts in brains of Down syndrome patients. Conclusion In general, there was only a moderate alteration of gene expression in ADAM10 overexpressing mice. Genes coding for pro-inflammatory or pro-apoptotic proteins were not over-represented among differentially regulated genes. Even a decrease of

Suppressed retinal degeneration in aged wild type and APPswe/PS1ΔE9 mice by bone marrow transplantation.

Directory of Open Access Journals (Sweden)

Yue Yang

Full Text Available Alzheimer's disease (AD is an age-related condition characterized by accumulation of neurotoxic amyloid β peptides (Aβ in brain and retina. Because bone marrow transplantation (BMT results in decreased cerebral Aβ in experimental AD, we hypothesized that BMT would mitigate retinal neurotoxicity through decreased retinal Aβ. To test this, we performed BMT in APPswe/PS1ΔE9 double transgenic mice using green fluorescent protein expressing wild type (wt mice as marrow donors. We first examined retinas from control, non-transplanted, aged AD mice and found a two-fold increase in microglia compared with wt mice, prominent inner retinal Aβ and paired helical filament-tau, and decreased retinal ganglion cell layer neurons. BMT resulted in near complete replacement of host retinal microglia with BMT-derived cells and normalized total AD retinal microglia to non-transplanted wt levels. Aβ and paired helical filament-tau were reduced (61.0% and 44.1% respectively in BMT-recipient AD mice, which had 20.8% more retinal ganglion cell layer neurons than non-transplanted AD controls. Interestingly, aged wt BMT recipients also had significantly more neurons (25.4% compared with non-transplanted aged wt controls. Quantitation of retinal ganglion cell layer neurons in young mice confirmed age-related retinal degeneration was mitigated by BMT. We found increased MHC class II expression in BMT-derived microglia and decreased oxidative damage in retinal ganglion cell layer neurons. Thus, BMT is neuroprotective in age-related as well as AD-related retinal degeneration, and may be a result of alterations in innate immune function and oxidative stress in BMT recipient mice.

Dopaminergic neuronal loss, reduced neurite complexity and autophagic abnormalities in transgenic mice expressing G2019S mutant LRRK2.

Directory of Open Access Journals (Sweden)

David Ramonet

2011-04-01

Full Text Available Mutations in the leucine-rich repeat kinase 2 (LRRK2 gene cause late-onset, autosomal dominant familial Parkinson's disease (PD and also contribute to idiopathic PD. LRRK2 mutations represent the most common cause of PD with clinical and neurochemical features that are largely indistinguishable from idiopathic disease. Currently, transgenic mice expressing wild-type or disease-causing mutants of LRRK2 have failed to produce overt neurodegeneration, although abnormalities in nigrostriatal dopaminergic neurotransmission have been observed. Here, we describe the development and characterization of transgenic mice expressing human LRRK2 bearing the familial PD mutations, R1441C and G2019S. Our study demonstrates that expression of G2019S mutant LRRK2 induces the degeneration of nigrostriatal pathway dopaminergic neurons in an age-dependent manner. In addition, we observe autophagic and mitochondrial abnormalities in the brains of aged G2019S LRRK2 mice and markedly reduced neurite complexity of cultured dopaminergic neurons. These new LRRK2 transgenic mice will provide important tools for understanding the mechanism(s through which familial mutations precipitate neuronal degeneration and PD.

Interleukin 37 expression in mice alters sleep responses to inflammatory agents and influenza virus infection

Directory of Open Access Journals (Sweden)

Christopher J. Davis

2017-06-01

Full Text Available Multiple interactions between the immune system and sleep are known, including the effects of microbial challenge on sleep or the effects of sleep loss on facets of the immune response. Cytokines regulate, in part, sleep and immune responses. Here we examine the role of an anti-inflammatory cytokine, interleukin-37 (IL-37 on sleep in a mouse strain that expresses human IL-37b (IL37tg mice. Constitutive expression of the IL-37 gene in the brains of these mice under resting conditions is low; however, upon an inflammatory stimulus, expression increases dramatically. We measured sleep in three conditions; (a under baseline conditions and after 6 h of sleep loss, (b after bolus intraperitoneal administration of lipopolysaccharide (LPS or IL-1β and (c after intranasal influenza virus challenge. Under baseline conditions, the IL37tg mice had 7% more spontaneous non-rapid eye movement sleep (NREMS during the light period than wild-type (WT mice. After sleep deprivation both WT mice and IL37tg mice slept an extra 21% and 12%, respectively, during the first 6 h of recovery. NREMS responses after sleep deprivation did not significantly differ between WT mice and IL37tg mice. However, in response to either IL-1β or LPS, the increases in time spent in NREMS were about four-fold greater in the WT mice than in the IL37tg mice. In contrast, in response to a low dose of mouse-adapted H1N1 influenza virus, sleep responses developed slowly over the 6 day recording period. By day 6, NREMS increased by 10% and REMS increased by 18% in the IL37tg mice compared to the WT mice. Further, by day 4 IL37tg mice lost less weight, remained more active, and retained their body temperatures closer to baseline values than WT mice. We conclude that conditions that promote IL-37 expression attenuate morbidity to severe inflammatory challenge.

Role of macrophages in age-related oxidative stress and lipofuscin accumulation in mice.

Science.gov (United States)

Vida, Carmen; de Toda, Irene Martínez; Cruces, Julia; Garrido, Antonio; Gonzalez-Sanchez, Mónica; De la Fuente, Mónica

2017-08-01

The age-related changes in the immune functions (immunosenescence) may be mediated by an increase of oxidative stress and damage affecting leukocytes. Although the "oxidation-inflammation" theory of aging proposes that phagocytes are the main immune cells contributing to "oxi-inflamm-aging", this idea has not been corroborated. The aim of this work was to characterize the age-related changes in several parameters of oxidative stress and immune function, as well as in lipofuscin accumulation ("a hallmark of aging"), in both total peritoneal leukocyte population and isolated peritoneal macrophages. Adult, mature, old and long-lived mice (7, 13, 18 and 30 months of age, respectively) were used. The xanthine oxidase (XO) activity-expression, basal levels of superoxide anion and ROS, catalase activity, oxidized (GSSG) and reduced (GSH) glutathione content and lipofuscin levels, as well as both phagocytosis and digestion capacity were evaluated. The results showed an age-related increase of oxidative stress and lipofuscin accumulation in murine peritoneal leukocytes, but especially in macrophages. Macrophages from old mice showed lower antioxidant defenses (catalase activity and GSH levels), higher oxidizing compounds (XO activity/expression and superoxide, ROS and GSSG levels) and lipofuscin levels, together with an impaired macrophage functions, in comparison to adults. In contrast, long-lived mice showed in their peritoneal leukocytes, and especially in macrophages, a well-preserved redox state and maintenance of their immune functions, all which could account for their high longevity. Interestingly, macrophages showed higher XO activity and lipofuscin accumulation than lymphocytes in all the ages analyzed. Our results support that macrophages play a central role in the chronic oxidative stress associated with aging, and the fact that phagocytes are key cells contributing to immunosenescence and "oxi-inflamm-aging". Moreover, the determination of oxidative stress and

Dietary broccoli mildly improves neuroinflammation in aged mice but does not reduce lipopolysaccharide-induced sickness behavior.

Science.gov (United States)

Townsend, Brigitte E; Chen, Yung-Ju; Jeffery, Elizabeth H; Johnson, Rodney W

2014-11-01

Aging is associated with oxidative stress and heightened inflammatory response to infection. Dietary interventions to reduce these changes are therefore desirable. Broccoli contains glucoraphanin, which is converted to sulforaphane (SFN) by plant myrosinase during cooking preparation or digestion. Sulforaphane increases antioxidant enzymes including NAD(P)H quinone oxidoreductase and heme oxygenase I and inhibits inflammatory cytokines. We hypothesized that dietary broccoli would support an antioxidant response in brain and periphery of aged mice and inhibit lipopolysaccharide (LPS)-induced inflammation and sickness. Young adult and aged mice were fed control or 10% broccoli diet for 28 days before an intraperitoneal LPS injection. Social interactions were assessed 2, 4, 8, and 24 hours after LPS, and mRNA was quantified in liver and brain at 24 hours. Dietary broccoli did not ameliorate LPS-induced decrease in social interactions in young or aged mice. Interleukin-1β (IL-1β) expression was unaffected by broccoli consumption but was induced by LPS in brain and liver of adult and aged mice. In addition, IL-1β was elevated in brain of aged mice without LPS. Broccoli consumption decreased age-elevated cytochrome b-245 β, an oxidative stress marker, and reduced glial activation markers in aged mice. Collectively, these data suggest that 10% broccoli diet provides a modest reduction in age-related oxidative stress and glial reactivity, but is insufficient to inhibit LPS-induced inflammation. Thus, it is likely that SFN would need to be provided in supplement form to control the inflammatory response to LPS. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Tumor radiation responses and tumor oxygenation in aging mice

International Nuclear Information System (INIS)

Rockwell, S.

1989-01-01

EMT6 mouse mammary tumors transplanted into aging mice are less sensitive to radiation than tumors growing in young adult animals. The experiments reported here compare the radiation dose-response curves defining the survivals of tumor cells in aging mice and in young adult mice. Cell survival curves were assessed in normal air-breathing mice and in mice asphyxiated with N 2 to produce uniform hypoxia throughout the tumors. Analyses of survival curves revealed that 41% of viable malignant cells were severely hypoxic in tumors in aging mice, while only 19% of the tumor cells in young adult animals were radiobiologically hypoxic. This did not appear to reflect anaemia in the old animals. Treatment of aging animals with a perfluorochemical emulsion plus carbogen (95% O 2 /5% CO 2 ) increased radiation response of the tumors, apparently by improving tumor oxygenation and decreasing the number of severely hypoxic, radiation resistant cells in the tumors. (author)

Homeostatic imbalance between apoptosis and cell renewal in the liver of premature aging Xpd mice.

Directory of Open Access Journals (Sweden)

Jung Yoon Park

2008-06-01

Full Text Available Unrepaired or misrepaired DNA damage has been implicated as a causal factor in cancer and aging. Xpd(TTD mice, harboring defects in nucleotide excision repair and transcription due to a mutation in the Xpd gene (R722W, display severe symptoms of premature aging but have a reduced incidence of cancer. To gain further insight into the molecular basis of the mutant-specific manifestation of age-related phenotypes, we used comparative microarray analysis of young and old female livers to discover gene expression signatures distinguishing Xpd(TTD mice from their age-matched wild type controls. We found a transcription signature of increased apoptosis in the Xpd(TTD mice, which was confirmed by in situ immunohistochemical analysis and found to be accompanied by increased proliferation. However, apoptosis rate exceeded the rate of proliferation, resulting in homeostatic imbalance. Interestingly, a metabolic response signature was observed involving decreased energy metabolism and reduced IGF-1 signaling, a major modulator of life span. We conclude that while the increased apoptotic response to endogenous DNA damage contributes to the accelerated aging phenotypes and the reduced cancer incidence observed in the Xpd(TTD mice, the signature of reduced energy metabolism is likely to reflect a compensatory adjustment to limit the increased genotoxic stress in these mutants. These results support a general model for premature aging in DNA repair deficient mice based on cellular responses to DNA damage that impair normal tissue homeostasis.

Over-expression of Stat5b confers protection against diabetes in the non-obese diabetic (NOD) mice via up-regulation of CD4{sup +}CD25{sup +} regulatory T cells

Energy Technology Data Exchange (ETDEWEB)

Jin, Yulan; Purohit, Sharad [Center for Biotechnology and Genomic Medicine, Georgia Health Sciences University, GA (United States); Department of Pathology, Medical College of Georgia, Georgia Health Sciences University, GA (United States); Chen, Xueqin; Yi, Bing [Center for Biotechnology and Genomic Medicine, Georgia Health Sciences University, GA (United States); She, Jin-Xiong, E-mail: jshe@georgiahealth.edu [Center for Biotechnology and Genomic Medicine, Georgia Health Sciences University, GA (United States); Department of Pathology, Medical College of Georgia, Georgia Health Sciences University, GA (United States)

2012-08-10

Highlights: Black-Right-Pointing-Pointer This is the first study to provide direct evidence of the role of Stat5b in NOD mice. Black-Right-Pointing-Pointer Over-expression of wild type Stat5b transgene protects NOD mice against diabetes. Black-Right-Pointing-Pointer This protection may be mediated by the up-regulation of CD4{sup +}CD25{sup +} Tregs. -- Abstract: The signal transducers and activators of transcription (STAT) family of proteins play a critical role in cytokine signaling required for fine tuning of immune regulation. Previous reports showed that a mutation (L327M) in the Stat5b protein leads to aberrant cytokine signaling in the NOD mice. To further elaborate the role of Stat5b in diabetes, we established a NOD transgenic mouse that over-expresses the wild type Stat5b gene. The incidences of spontaneous diabetes as well as cyclophosphamide-induced diabetes were significantly reduced and delayed in the Stat5b transgenic NOD mice compared to their littermate controls. The total cell numbers of CD4{sup +} T cells and especially CD8{sup +} T cells in the spleen and pancreatic lymph node were increased in the Stat5b transgenic NOD mice. Consistent with these findings, CD4{sup +} and CD8{sup +} T cells from the Stat5b transgenic NOD mice showed a higher proliferation capacity and up-regulation of multiple cytokines including IL-2, IFN-{gamma}, TNF-{alpha} and IL-10 as well as anti-apoptotic gene Bcl-xl. Furthermore, the number and proportion of CD4{sup +}CD25{sup +} regulatory T cells were significantly increased in transgenic mice although in vitro suppression ability of the regulatory T-cells was not affected by the transgene. Our results suggest that Stat5b confers protection against diabetes in the NOD mice by regulating the numbers and function of multiple immune cell types, especially by up-regulating CD4{sup +}CD25{sup +} regulatory T cells.

Advanced age-related denervation and fiber-type grouping in skeletal muscle of SOD1 knockout mice.

Science.gov (United States)

Kostrominova, Tatiana Y

2010-11-30

In this study skeletal muscles from 1.5- and 10-month-old Cu/Zn superoxide dismutase (SOD1) homozygous knockout (JLSod1(-/-)) mice obtained from The Jackson Laboratory (C57Bl6/129SvEv background) were compared with muscles from age- and sex-matched heterozygous (JLSod1(+/-)) littermates. The results of this study were compared with previously published data on two different strains of Sod1(-/-) mice: one from Dr. Epstein's laboratory (ELSod1(-/-); C57Bl6 background) and the other from Cephalon, Inc. (CSod1(-/-); 129/CD-1 background). Grouping of succinate dehydrogenase-positive fibers characterized muscles of Sod1(-/-) mice from all three strains. The 10-month-old Sod1(-/-)C and JL mice displayed pronounced denervation of the gastrocnemius muscle, whereas the ELSod1(-/-) mice displayed a small degree of denervation at this age, but developed accelerated age-related denervation later on. Denervation markers were up-regulated in skeletal muscle of 10-month-old JLSod1(-/-) mice. This study is the first to show that metallothionein mRNA and protein expression was up-regulated in the skeletal muscle of 10-month-old JLSod1(-/-) mice and was mostly localized to the small atrophic muscle fibers. In conclusion, all three strains of Sod1(-/-) mice develop accelerated age-related muscle denervation, but the genetic background has significant influence on the progress of denervation. Copyright © 2010 Elsevier Inc. All rights reserved.

Effects of velvet antler polypeptide on sexual behavior and testosterone synthesis in aging male mice.

Science.gov (United States)

Zang, Zhi-Jun; Tang, Hong-Feng; Tuo, Ying; Xing, Wei-Jie; Ji, Su-Yun; Gao, Yong; Deng, Chun-Hua

2016-01-01

Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo.

Inducible knockdown of pregnancy-associated plasma protein-A gene expression in adult female mice extends life span.

Science.gov (United States)

Bale, Laurie K; West, Sally A; Conover, Cheryl A

2017-08-01

Pregnancy-associated plasma protein-A (PAPP-A) knockout (KO) mice, generated through homologous recombination in embryonic stem cells, have a significantly increased lifespan compared to wild-type littermates. However, it is unknown whether this longevity advantage would pertain to PAPP-A gene deletion in adult animals. In the present study, we used tamoxifen (Tam)-inducible Cre recombinase-mediated excision of the floxed PAPP-A (fPAPP-A) gene in mice at 5 months of age. fPAPP-A mice, which were either positive (pos) or negative (neg) for Tam-Cre, received Tam treatment with quarterly boosters. Only female mice could be used with this experimental design. fPAPP-A/neg and fPAPP-A/pos mice had similar weights at the start of the experiment and showed equivalent weight gain. We found that fPAPP-A/pos mice had a significant extension of life span (P = 0.005). The median life span was increased by 21% for fPAPP-A/pos compared to fPAPP-A/neg mice. Analysis of mortality in life span quartiles indicated that the proportion of deaths of fPAPP-A/pos mice were lower than fPAPP-A/neg mice at young adult ages (P = 0.002 for 601-800 days) and higher than fPAPP-A/neg mice at older ages (P = 0.004 for >1000 days). Thus, survival curves and age-specific mortality indicate that female mice with knockdown of PAPP-A gene expression as adults have an extended healthy life span. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Identification of novel genes associated with renal tertiary lymphoid organ formation in aging mice.

Science.gov (United States)

Huang, Yuan; Caputo, Christina R; Noordmans, Gerda A; Yazdani, Saleh; Monteiro, Luiz Henrique; van den Born, Jaap; van Goor, Harry; Heeringa, Peter; Korstanje, Ron; Hillebrands, Jan-Luuk

2014-01-01

A hallmark of aging-related organ deterioration is a dysregulated immune response characterized by pathologic leukocyte infiltration of affected tissues. Mechanisms and genes involved are as yet unknown. To identify genes associated with aging-related renal infiltration, we analyzed kidneys from aged mice (≥20 strains) for infiltrating leukocytes followed by Haplotype Association Mapping (HAM) analysis. Immunohistochemistry revealed CD45+ cell clusters (predominantly T and B cells) in perivascular areas coinciding with PNAd+ high endothelial venules and podoplanin+ lymph vessels indicative of tertiary lymphoid organs. Cumulative cluster size increased with age (analyzed at 6, 12 and 20 months). Based on the presence or absence of clusters in male and female mice at 20 months, HAM analysis revealed significant associations with loci on Chr1, Chr2, Chr8 and Chr14 in male mice, and with loci on Chr4, Chr7, Chr13 and Chr14 in female mice. Wisp2 (Chr2) showed the strongest association (P = 5.00×10(-137)) in male mice; Ctnnbip1 (P = 6.42×10(-267)) and Tnfrsf8 (P = 5.42×10(-245)) (both on Chr4) showed the strongest association in female mice. Both Wisp2 and Ctnnbip1 are part of the Wnt-signaling pathway and the encoded proteins were expressed within the tertiary lymphoid organs. In conclusion, this study revealed differential lymphocytic infiltration and tertiary lymphoid organ formation in aged mouse kidneys across different inbred mouse strains. HAM analysis identified candidate genes involved in the Wnt-signaling pathway that may be causally linked to tertiary lymphoid organ formation.

Ovarian Germline Stem Cells (OGSCs and the Hippo Signaling Pathway Association with Physiological and Pathological Ovarian Aging in Mice

Directory of Open Access Journals (Sweden)

Jia Li

2015-07-01

Full Text Available Background: The Hippo signaling pathway plays fundamental roles in stem cell maintenance in a variety of tissues and has thus implications for stem cell biology. Key components of this recently discovered pathway have been shown to be associated with primordial follicle activation. However, whether the Hippo signaling pathway plays a role in the development of Ovarian Germline Stem Cells (OGSCs during physiological and pathological ovarian aging in mice is unknown. Methods: Mice at the age of 7 days (7D, or of 2, 10, or 20 months (2M, 10M, 20M and mice at 2M treated with TPT and CY/BUS drugs were selected as physiological and pathological ovarian aging models, respectively. Immunohistochemistry was used to assess the development of follicles, and the co-localization of genes characteristic of OGSCs with MST1, LATS2 and YAP1 was assessed by immunofluorescence, western blotting and real-time PCR methods. Results: The Hippo signal pathway and MVH/OCT4 genes were co-expressed in the mouse ovarian cortex. The level and co-localization of LATS2, MST1, MVH, and OCT4 were significantly decreased with increased age, but YAP1 was more prevalent in the mouse ovarian cortex of 2M mice than 7D mice and was not observed in 20M mice. Furthermore, YAP1, MVH, and OCT4 were gradually decreased after TPT and CY/BUS treatment, and LATS2 mRNA and protein up-regulation persisted in TPT- and CY/BUS-treated mice. However, the expression of MST1 was lower in the TPT and CY/BUS groups compared with the control group. In addition, pYAP1 protein showed the highest expression in the ovarian cortexes of 7D mice compared with 20M mice, and the value of pYAP1/YAP1 decreased from 7D to 20M. Moreover, pYAP1 decreased in the TPT- and CY/BUS-treated groups, but the value of pYAP1/YAP1 increased in these groups. Conclusion: Taken together, our results show that the Hippo signaling pathway is associated with the changes that take place in OGSCs during physiological and pathological

Voluntary Exercise Promotes Glymphatic Clearance of Amyloid Beta and Reduces the Activation of Astrocytes and Microglia in Aged Mice.

Science.gov (United States)

He, Xiao-Fei; Liu, Dong-Xu; Zhang, Qun; Liang, Feng-Ying; Dai, Guang-Yan; Zeng, Jin-Sheng; Pei, Zhong; Xu, Guang-Qing; Lan, Yue

2017-01-01

Age is characterized by chronic inflammation, leading to synaptic dysfunction and dementia because the clearance of protein waste is reduced. The clearance of proteins depends partly on the permeation of the blood-brain barrier (BBB) or on the exchange of water and soluble contents between the cerebrospinal fluid (CSF) and the interstitial fluid (ISF). A wealth of evidence indicates that physical exercise improves memory and cognition in neurodegenerative diseases during aging, such as Alzheimer's disease (AD), but the influence of physical training on glymphatic clearance, BBB permeability and neuroinflammation remains unclear. In this study, glymphatic clearance and BBB permeability were evaluated in aged mice using in vivo two-photon imaging. The mice performed voluntary wheel running exercise and their water-maze cognition was assessed; the expression of the astrocytic water channel aquaporin 4 (AQP4), astrocyte and microglial activation, and the accumulation of amyloid beta (Aβ) were evaluated with immunofluorescence or an enzyme-linked immunosorbent assay (ELISA); synaptic function was investigated with Thy1 -green fluorescent protein (GFP) transgenic mice and immunofluorescent staining. Voluntary wheel running significantly improved water-maze cognition in the aged mice, accelerated the efficiency of glymphatic clearance, but which did not affect BBB permeability. The numbers of activated astrocytes and microglia decreased, AQP4 expression increased, and the distribution of astrocytic AQP4 was rearranged. Aβ accumulation decreased, whereas dendrites, dendritic spines and postsynaptic density protein (PSD95) increased. Our study suggests that voluntary wheel running accelerated glymphatic clearance but not BBB permeation, improved astrocytic AQP4 expression and polarization, attenuated the accumulation of amyloid plaques and neuroinflammation, and ultimately protected mice against synaptic dysfunction and a decline in spatial cognition. These data suggest

Voluntary Exercise Promotes Glymphatic Clearance of Amyloid Beta and Reduces the Activation of Astrocytes and Microglia in Aged Mice

Directory of Open Access Journals (Sweden)

Xiao-fei He

2017-05-01

Full Text Available Age is characterized by chronic inflammation, leading to synaptic dysfunction and dementia because the clearance of protein waste is reduced. The clearance of proteins depends partly on the permeation of the blood–brain barrier (BBB or on the exchange of water and soluble contents between the cerebrospinal fluid (CSF and the interstitial fluid (ISF. A wealth of evidence indicates that physical exercise improves memory and cognition in neurodegenerative diseases during aging, such as Alzheimer’s disease (AD, but the influence of physical training on glymphatic clearance, BBB permeability and neuroinflammation remains unclear. In this study, glymphatic clearance and BBB permeability were evaluated in aged mice using in vivo two-photon imaging. The mice performed voluntary wheel running exercise and their water-maze cognition was assessed; the expression of the astrocytic water channel aquaporin 4 (AQP4, astrocyte and microglial activation, and the accumulation of amyloid beta (Aβ were evaluated with immunofluorescence or an enzyme-linked immunosorbent assay (ELISA; synaptic function was investigated with Thy1–green fluorescent protein (GFP transgenic mice and immunofluorescent staining. Voluntary wheel running significantly improved water-maze cognition in the aged mice, accelerated the efficiency of glymphatic clearance, but which did not affect BBB permeability. The numbers of activated astrocytes and microglia decreased, AQP4 expression increased, and the distribution of astrocytic AQP4 was rearranged. Aβ accumulation decreased, whereas dendrites, dendritic spines and postsynaptic density protein (PSD95 increased. Our study suggests that voluntary wheel running accelerated glymphatic clearance but not BBB permeation, improved astrocytic AQP4 expression and polarization, attenuated the accumulation of amyloid plaques and neuroinflammation, and ultimately protected mice against synaptic dysfunction and a decline in spatial cognition

Peripheral surgical wounding and age-dependent neuroinflammation in mice.

Directory of Open Access Journals (Sweden)

Zhipeng Xu

Full Text Available Post-operative cognitive dysfunction is associated with morbidity and mortality. However, its neuropathogenesis remains largely to be determined. Neuroinflammation and accumulation of β-amyloid (Aβ have been reported to contribute to cognitive dysfunction in humans and cognitive impairment in animals. Our recent studies have established a pre-clinical model in mice, and have found that the peripheral surgical wounding without the influence of general anesthesia induces an age-dependent Aβ accumulation and cognitive impairment in mice. We therefore set out to assess the effects of peripheral surgical wounding, in the absence of general anesthesia, on neuroinflammation in mice with different ages. Abdominal surgery under local anesthesia was established in 9 and 18 month-old mice. The levels of tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6, Iba1 positive cells (the marker of microglia activation, CD33, and cognitive function in mice were determined. The peripheral surgical wounding increased the levels of TNF-α, IL-6, and Iba1 positive cells in the hippocampus of both 9 and 18 month-old mice, and age potentiated these effects. The peripheral surgical wounding increased the levels of CD33 in the hippocampus of 18, but not 9, month-old mice. Finally, anti-inflammatory drug ibuprofen ameliorated the peripheral surgical wounding-induced cognitive impairment in 18 month-old mice. These data suggested that the peripheral surgical wounding could induce an age-dependent neuroinflammation and elevation of CD33 levels in the hippocampus of mice, which could lead to cognitive impairment in aged mice. Pending further studies, anti-inflammatory therapies may reduce the risk of postoperative cognitive dysfunction in elderly patients.

Age-related changes in body composition of bovine growth hormone transgenic mice.

Science.gov (United States)

Palmer, Amanda J; Chung, Min-Yu; List, Edward O; Walker, Jennifer; Okada, Shigeru; Kopchick, John J; Berryman, Darlene E

2009-03-01

GH has a significant impact on body composition due to distinct anabolic and catabolic effects on lean and fat mass, respectively. Several studies have assessed body composition in mice expressing a GH transgene. Whereas all studies report enhanced growth of transgenic mice as compared with littermate controls, there are inconsistencies in terms of the relative proportion of lean mass to fat mass in these animals. The purpose of this study was to characterize the accumulation of adipose and lean mass with age and according to gender in a bovine (b) GH transgenic mouse line. Weight and body composition measurements were assessed in male and female bGH mice with corresponding littermate controls in the C57BL/6J genetic background. Body composition measurements began at 6 wk and continued through 1 yr of age. At the conclusion of the study, tissue weights were determined and triglyceride content was quantified in liver and kidney. Although body weights for bGH mice were significantly greater than their corresponding littermate controls at all time points, body composition measurements revealed an unexpected transition midway through analyses. That is, younger bGH mice had relatively more fat mass than nontransgenic littermates, whereas bGH mice became significantly leaner than controls by 4 months in males and 6 months in females. These results reveal the importance in timing and gender when conducting studies related to body composition or lean and fat tissue in GH transgenic mice or in other genetically manipulated mouse strains in which body composition may be impacted.

Influence of age on brain edema formation, secondary brain damage and inflammatory response after brain trauma in mice.

Directory of Open Access Journals (Sweden)

Ralph Timaru-Kast

Full Text Available After traumatic brain injury (TBI elderly patients suffer from higher mortality rate and worse functional outcome compared to young patients. However, experimental TBI research is primarily performed in young animals. Aim of the present study was to clarify whether age affects functional outcome, neuroinflammation and secondary brain damage after brain trauma in mice. Young (2 months and old (21 months male C57Bl6N mice were anesthetized and subjected to a controlled cortical impact injury (CCI on the right parietal cortex. Animals of both ages were randomly assigned to 15 min, 24 h, and 72 h survival. At the end of the observation periods, contusion volume, brain water content, neurologic function, cerebral and systemic inflammation (CD3+ T cell migration, inflammatory cytokine expression in brain and lung, blood differential cell count were determined. Old animals showed worse neurological function 72 h after CCI and a high mortality rate (19.2% compared to young (0%. This did not correlate with histopathological damage, as contusion volumes were equal in both age groups. Although a more pronounced brain edema formation was detected in old mice 24 hours after TBI, lack of correlation between brain water content and neurological deficit indicated that brain edema formation is not solely responsible for age-dependent differences in neurological outcome. Brains of old naïve mice were about 8% smaller compared to young naïve brains, suggesting age-related brain atrophy with possible decline in plasticity. Onset of cerebral inflammation started earlier and primarily ipsilateral to damage in old mice, whereas in young mice inflammation was delayed and present in both hemispheres with a characteristic T cell migration pattern. Pulmonary interleukin 1β expression was up-regulated after cerebral injury only in young, not aged mice. The results therefore indicate that old animals are prone to functional deficits and strong ipsilateral cerebral

Ageing Fxr deficient mice develop increased energy expenditure, improved glucose control and liver damage resembling NASH.

Directory of Open Access Journals (Sweden)

Mikael Bjursell

Full Text Available Nuclear receptor subfamily 1, group H, member 4 (Nr1h4, FXR is a bile acid activated nuclear receptor mainly expressed in the liver, intestine, kidney and adrenal glands. Upon activation, the primary function is to suppress cholesterol 7 alpha-hydroxylase (Cyp7a1, the rate-limiting enzyme in the classic or neutral bile acid synthesis pathway. In the present study, a novel Fxr deficient mouse line was created and studied with respect to metabolism and liver function in ageing mice fed chow diet. The Fxr deficient mice were similar to wild type mice in terms of body weight, body composition, energy intake and expenditure as well as behaviours at a young age. However, from 15 weeks of age and onwards, the Fxr deficient mice had almost no body weight increase up to 39 weeks of age mainly because of lower body fat mass. The lower body weight gain was associated with increased energy expenditure that was not compensated by increased food intake. Fasting levels of glucose and insulin were lower and glucose tolerance was improved in old and lean Fxr deficient mice. However, the Fxr deficient mice displayed significantly increased liver weight, steatosis, hepatocyte ballooning degeneration and lobular inflammation together with elevated plasma levels of ALT, bilirubin and bile acids, findings compatible with non-alcoholic steatohepatitis (NASH and cholestasis. In conclusion, ageing Fxr deficient mice display late onset leanness associated with elevated energy expenditure and improved glucose control but develop severe NASH-like liver pathology.

Ageing Fxr deficient mice develop increased energy expenditure, improved glucose control and liver damage resembling NASH.

Science.gov (United States)

Bjursell, Mikael; Wedin, Marianne; Admyre, Therése; Hermansson, Majlis; Böttcher, Gerhard; Göransson, Melker; Lindén, Daniel; Bamberg, Krister; Oscarsson, Jan; Bohlooly-Y, Mohammad

2013-01-01

Nuclear receptor subfamily 1, group H, member 4 (Nr1h4, FXR) is a bile acid activated nuclear receptor mainly expressed in the liver, intestine, kidney and adrenal glands. Upon activation, the primary function is to suppress cholesterol 7 alpha-hydroxylase (Cyp7a1), the rate-limiting enzyme in the classic or neutral bile acid synthesis pathway. In the present study, a novel Fxr deficient mouse line was created and studied with respect to metabolism and liver function in ageing mice fed chow diet. The Fxr deficient mice were similar to wild type mice in terms of body weight, body composition, energy intake and expenditure as well as behaviours at a young age. However, from 15 weeks of age and onwards, the Fxr deficient mice had almost no body weight increase up to 39 weeks of age mainly because of lower body fat mass. The lower body weight gain was associated with increased energy expenditure that was not compensated by increased food intake. Fasting levels of glucose and insulin were lower and glucose tolerance was improved in old and lean Fxr deficient mice. However, the Fxr deficient mice displayed significantly increased liver weight, steatosis, hepatocyte ballooning degeneration and lobular inflammation together with elevated plasma levels of ALT, bilirubin and bile acids, findings compatible with non-alcoholic steatohepatitis (NASH) and cholestasis. In conclusion, ageing Fxr deficient mice display late onset leanness associated with elevated energy expenditure and improved glucose control but develop severe NASH-like liver pathology.

High Intensity Interval Training Improves Physical Performance and Frailty in Aged Mice.

Science.gov (United States)

Seldeen, Kenneth Ladd; Lasky, Ginger; Leiker, Merced Marie; Pang, Manhui; Personius, Kirkwood Ely; Troen, Bruce Robert

2018-03-14

Sarcopenia and frailty are highly prevalent in older individuals, increasing the risk of disability and loss of independence. High intensity interval training (HIIT) may provide a robust intervention for both sarcopenia and frailty by achieving both strength and endurance benefits with lower time commitments than other exercise regimens. To better understand the impacts of HIIT during aging, we compared 24-month-old C57BL/6J sedentary mice with those that were administered 10-minute uphill treadmill HIIT sessions three times per week over 16 weeks. Baseline and end point assessments included body composition, physical performance, and frailty based on criteria from the Fried physical frailty scale. HIIT-trained mice demonstrated dramatic improvement in grip strength (HIIT 10.9% vs -3.9% in sedentary mice), treadmill endurance (32.6% vs -2.0%), and gait speed (107.0% vs 39.0%). Muscles from HIIT mice also exhibited greater mass, larger fiber size, and an increase in mitochondrial biomass. Furthermore, HIIT exercise led to a dramatic reduction in frailty scores in five of six mice that were frail or prefrail at baseline, with four ultimately becoming nonfrail. The uphill treadmill HIIT exercise sessions were well tolerated by aged mice and led to performance gains, improvement in underlying muscle physiology, and reduction in frailty.

NMDA and kainate receptor expression, long-term potentiation, and neurogenesis in the hippocampus of long-lived Ames dwarf mice.

Science.gov (United States)

Sharma, Sunita; Darland, Diane; Lei, Saobo; Rakoczy, Sharlene; Brown-Borg, Holly M

2012-06-01

In the current study, we investigated changes in N-methyl D-aspartate (NMDA) and kainate receptor expression, long-term potentiation (LTP), and neurogenesis in response to neurotoxic stress in long-living Ames dwarf mice. We hypothesized that Ames dwarf mice have enhanced neurogenesis that enables retention of spatial learning and memory with age and promotes neurogenesis in response to injury. Levels of the NMDA receptors (NR)1, NR2A, NR2B, and the kainate receptor (KAR)2 were increased in Ames dwarf mice, relative to wild-type littermates. Quantitative assessment of the excitatory postsynaptic potential in Schaffer collaterals in hippocampal slices from Ames dwarf mice showed an increased response in high-frequency induced LTP over time compared with wild type. Kainic acid (KA) injection was used to promote neurotoxic stress-induced neurogenesis. KA mildly increased the number of doublecortin-positive neurons in wild-type mice, but the response was significantly enhanced in the Ames dwarf mice. Collectively, these data support our hypothesis that the enhanced learning and memory associated with the Ames dwarf mouse may be due to elevated levels of NMDA and KA receptors in hippocampus and their ability to continue producing new neurons in response to neuronal damage.

Cimetidine attenuates vinorelbine-induced phlebitis in mice by militating E-selectin expression.

Science.gov (United States)

Wang, Zhuo; Ma, Lijuan; Wang, Xuebin; Cai, Heping; Huang, Jin; Liu, Jiyong; Hu, Jinhong; Su, Dingfeng

2014-08-01

We investigated E-selectin expression in mice and rabbits with vinorelbine-induced phlebitis and the effect of cimetidine. To find the relationship between E-selectin expression and vinorelbine-induced phlebitis. Mouse and rabbit model of vinorelbine-induced phlebitis was established by intravenous infusion of vinorelbine. Pathological observation, molecular-biological determination of E-selectin and protein function of it was evaluated. Grossly, we observed swelling, edema and cord-like vessel changes in mice receiving vinorelbine but only mild edema in mice pretreated with cimetidine. Pathological scoring yielded a total score of 37 for vinorelbine-treated mice and 17 for mice pretreated with cimetidine (P phlebitis in mice probably by suppressing increased expression of E-selectin.

Ursodeoxycholic acid decreases age-related adiposity and inflammation in mice

Science.gov (United States)

Oh, Ah-Reum; Bae, Jin-Sik; Lee, Junghoon; Shin, Eunji; Oh, Byung-Chul; Park, Sang-Chul; Cha, Ji-Young

2016-01-01

Ursodeoxycholic acid (UDCA), a natural, hydrophilic nontoxic bile acid, is clinically effective for treating cholestatic and chronic liver diseases. We investigated the chronic effects of UDCA on age-related lipid homeostasis and underlying molecular mechanisms. Twenty-week-old C57BL/6 male and female mice were fed a diet with or without 0.3% UDCA supplementation for 25 weeks. UDCA significantly reduced weight gain, adiposity, hepatic triglyceride, and hepatic cholesterol without incidental hepatic injury. UDCA-mediated hepatic triglyceride reduction was associated with downregulated hepatic expression of peroxisome proliferator-activated receptor-γ, and of other genes involved in lipogenesis (Chrebp, Acaca, Fasn, Scd1, and Me1) and fatty acid uptake (Ldlr, Cd36). The inflammatory cytokines Tnfa, Ccl2, and Il6 were significantly decreased in liver and/or white adipose tissues of UDCA-fed mice. These data suggest that UDCA exerts beneficial effects on age-related metabolic disorders by lowering the hepatic lipid accumulation, while concurrently reducing hepatocyte and adipocyte susceptibility to inflammatory stimuli. [BMB Reports 2016; 49(2): 105-110] PMID:26350747

Manipulation of Ovarian Function Significantly Influenced Sarcopenia in Postreproductive-Age Mice

Directory of Open Access Journals (Sweden)

Rhett L. Peterson

2016-01-01

Full Text Available Previously, transplantation of ovaries from young cycling mice into old postreproductive-age mice increased life span. We anticipated that the same factors that increased life span could also influence health span. Female CBA/J mice received new (60 d ovaries at 12 and 17 months of age and were evaluated at 16 and 25 months of age, respectively. There were no significant differences in body weight among any age or treatment group. The percentage of fat mass was significantly increased at 13 and 16 months of age but was reduced by ovarian transplantation in 16-month-old mice. The percentages of lean body mass and total body water were significantly reduced in 13-month-old control mice but were restored in 16- and 25-month-old recipient mice by ovarian transplantation to the levels found in six-month-old control mice. In summary, we have shown that skeletal muscle mass, which is negatively influenced by aging, can be positively influenced or restored by reestablishment of active ovarian function in aged female mice. These findings provide strong incentive for further investigation of the positive influence of young ovaries on restoration of health in postreproductive females.

Alterations in endocytic protein expression with increasing age in the transgenic APP695 V717I London mouse model of amyloid pathology: implications for Alzheimer's disease.

Science.gov (United States)

Thomas, Rhian S; Alsaqati, Mouhamed; Bice, Justin S; Hvoslef-Eide, Martha; Good, Mark A; Kidd, Emma J

2017-10-18

A major risk factor for the development of Alzheimer's disease (AD) is increasing age, but the reason behind this association has not been identified. It is thought that the changes in endocytosis seen in AD patients are causal for this condition. Thus, we hypothesized that the increased risk of developing AD associated with ageing may be because of changes in endocytosis. We investigated using Western blotting whether the expression of endocytic proteins involved in clathrin-mediated and clathrin-independent endocytosis are altered by increasing age in a mouse model of amyloid pathology. We used mice transgenic for human amyloid precursor protein containing the V717I London mutation. We compared the London mutation mice with age-matched wild-type (WT) controls at three ages, 3, 9 and 18 months, representing different stages in the development of pathology in this model. Having verified that the London mutation mice overexpressed amyloid precursor protein and β-amyloid, we found that the expression of the smallest isoform of PICALM, a key protein involved in the regulation of clathrin-coated pit formation, was significantly increased in WT mice, but decreased in the London mutation mice with age. PICALM levels in WT 18-month mice and clathrin levels in WT 9-month mice were significantly higher than those in the London mutation mice of the same ages. The expression of caveolin-1, involved in clathrin-independent endocytosis, was significantly increased with age in all mice. Our results suggest that endocytic processes could be altered by the ageing process and such changes could partly explain the association between ageing and AD.

Ischemic postconditioning confers cardioprotection and prevents reduction of Trx-1 in young mice, but not in middle-aged and old mice.

Science.gov (United States)

Perez, Virginia; D Annunzio, Verónica; Mazo, Tamara; Marchini, Timoteo; Caceres, Lourdes; Evelson, Pablo; Gelpi, Ricardo J

2016-04-01

Thioredoxin-1 (Trx-1) is part of an antioxidant system that maintains the cell redox homeostasis but their role on ischemic postconditioning (PostC) is unknown. The aim of this work was to determine whether Trx-1 participates in the cardioprotective mechanism of PostC in young, middle-aged, and old mice. Male FVB young (Y: 3 month-old), middle-aged (MA: 12 month-old), and old (O: 20 month-old) mice were used. Langendorff-perfused hearts were subjected to 30 min of ischemia and 120 min of reperfusion (I/R group). After ischemia, we performed 6 cycles of R/I (10 s each) followed by 120 min of reperfusion (PostC group). We measured the infarct size (triphenyltetrazolium); Trx-1, total and phosphorylated Akt, and GSK3β expression (Western blot); and the GSH/GSSG ratio (HPLC). PostC reduced the infarct size in young mice (I/R-Y: 52.3 ± 2.4 vs. PostC-Y: 40.0 ± 1.9, p Trx-1 expression decreased after I/R, and the PostC prevented the protein degradation in young animals (I/R-Y: 1.05 ± 0.1 vs. PostC-Y: 0.52 ± .0.07, p Trx-1 degradation, decreasing oxidative stress and allowing the activation of Akt and GSK3β to exert its cardioprotective effect. This protection mechanism is not activated in middle-aged and old animals.

Conditional Expression of the Androgen Receptor Increases Susceptibility of Bladder Cancer in Mice.

Directory of Open Access Journals (Sweden)

Daniel T Johnson

Full Text Available Bladder cancer represents a significant human tumor burden, accounting for about 7.7% and 2.4% of all cancer cases in males and females, respectively. While men have a higher risk of developing bladder cancer, women tend to present at a later stage of disease and with more aggressive tumors. Previous studies have suggested a promotional role of androgen signaling in enhancing bladder cancer development. To directly assess the role of androgens in bladder tumorigenesis, we have developed a novel transgenic mouse strain, R26hARLoxP/+:Upk3aGCE/+, in which the human AR transgene is conditionally expressed in bladder urothelium. Intriguingly, both male and female R26hARLoxP/+:Upk3aGCE/+ mice display a higher incidence of urothelial cell carcinoma (UCC than the age and sex matched control littermates in response to the carcinogen, N-butyl-N-(4-hydroxybutyl nitrosamine (BBN. We detect expression of the human AR transgene in CK5-positive and p63-positive basal cells in bladder urothelium. Further analyses of UCC tissues from R26hARLoxP/+:Upk3aGCE/+ mice showed that the majority of tumor cells are of urothelial basal cell origin. Positive immunostaining of transgenic AR protein was observed in the majority of tumor cells of the transgenic mice, providing a link between transgenic AR expression and oncogenic transformation. We observed an increase in Ki67 positive cells within the UCC lesions of transgenic AR mice. Manipulating endogenous androgen levels by castration and androgen supplementation directly affected bladder tumor development in male and female R26hARLoxP/+:Upk3aGCE/+ mice, respectively. Taken together, our data demonstrate for the first time that conditional activation of transgenic AR expression in bladder urothelium enhances carciongen-induced bladder tumor formation in mice. This new AR transgenic mouse line mimics certain features of human bladder cancer and can be used to study bladder tumorigenesis and for drug development.

Sox4 Links Tumor Suppression to Accelerated Aging in Mice by Modulating Stem Cell Activation

Directory of Open Access Journals (Sweden)

Miguel Foronda

2014-07-01

Full Text Available Sox4 expression is restricted in mammals to embryonic structures and some adult tissues, such as lymphoid organs, pancreas, intestine, and skin. During embryogenesis, Sox4 regulates mesenchymal and neural progenitor survival, as well as lymphocyte and myeloid differentiation, and contributes to pancreas, bone, and heart development. Aberrant Sox4 expression is linked to malignant transformation and metastasis in several types of cancer. To understand the role of Sox4 in the adult organism, we first generated mice with reduced whole-body Sox4 expression. These mice display accelerated aging and reduced cancer incidence. To specifically address a role for Sox4 in adult stem cells, we conditionally deleted Sox4 (Sox4cKO in stratified epithelia. Sox4cKO mice show increased skin stem cell quiescence and resistance to chemical carcinogenesis concomitantly with downregulation of cell cycle, DNA repair, and activated hair follicle stem cell pathways. Altogether, these findings highlight the importance of Sox4 in regulating adult tissue homeostasis and cancer.

Cancer-Predicting Gene Expression Changes in Colonic Mucosa of Western Diet Fed Mlh1 +/- Mice

Science.gov (United States)

Dermadi Bebek, Denis; Valo, Satu; Reyhani, Nima; Ollila, Saara; Päivärinta, Essi; Peltomäki, Päivi; Mutanen, Marja; Nyström, Minna

2013-01-01

Colorectal cancer (CRC) is the second most common cause of cancer-related deaths in the Western world and interactions between genetic and environmental factors, including diet, are suggested to play a critical role in its etiology. We conducted a long-term feeding experiment in the mouse to address gene expression and methylation changes arising in histologically normal colonic mucosa as putative cancer-predisposing events available for early detection. The expression of 94 growth-regulatory genes previously linked to human CRC was studied at two time points (5 weeks and 12 months of age) in the heterozygote Mlh1 +/- mice, an animal model for human Lynch syndrome (LS), and wild type Mlh1 +/+ littermates, fed by either Western-style (WD) or AIN-93G control diet. In mice fed with WD, proximal colon mucosa, the predominant site of cancer formation in LS, exhibited a significant expression decrease in tumor suppressor genes, Dkk1, Hoxd1, Slc5a8, and Socs1, the latter two only in the Mlh1 +/- mice. Reduced mRNA expression was accompanied by increased promoter methylation of the respective genes. The strongest expression decrease (7.3 fold) together with a significant increase in its promoter methylation was seen in Dkk1, an antagonist of the canonical Wnt signaling pathway. Furthermore, the inactivation of Dkk1 seems to predispose to neoplasias in the proximal colon. This and the fact that Mlh1 which showed only modest methylation was still expressed in both Mlh1 +/- and Mlh1 +/+ mice indicate that the expression decreases and the inactivation of Dkk1 in particular is a prominent early marker for colon oncogenesis. PMID:24204690

Cancer-predicting gene expression changes in colonic mucosa of Western diet fed Mlh1+/- mice.

Directory of Open Access Journals (Sweden)

Marjaana Pussila

Full Text Available Colorectal cancer (CRC is the second most common cause of cancer-related deaths in the Western world and interactions between genetic and environmental factors, including diet, are suggested to play a critical role in its etiology. We conducted a long-term feeding experiment in the mouse to address gene expression and methylation changes arising in histologically normal colonic mucosa as putative cancer-predisposing events available for early detection. The expression of 94 growth-regulatory genes previously linked to human CRC was studied at two time points (5 weeks and 12 months of age in the heterozygote Mlh1(+/- mice, an animal model for human Lynch syndrome (LS, and wild type Mlh1(+/+ littermates, fed by either Western-style (WD or AIN-93G control diet. In mice fed with WD, proximal colon mucosa, the predominant site of cancer formation in LS, exhibited a significant expression decrease in tumor suppressor genes, Dkk1, Hoxd1, Slc5a8, and Socs1, the latter two only in the Mlh1(+/- mice. Reduced mRNA expression was accompanied by increased promoter methylation of the respective genes. The strongest expression decrease (7.3 fold together with a significant increase in its promoter methylation was seen in Dkk1, an antagonist of the canonical Wnt signaling pathway. Furthermore, the inactivation of Dkk1 seems to predispose to neoplasias in the proximal colon. This and the fact that Mlh1 which showed only modest methylation was still expressed in both Mlh1(+/- and Mlh1(+/+ mice indicate that the expression decreases and the inactivation of Dkk1 in particular is a prominent early marker for colon oncogenesis.

Fasting and Fast Food Diet Play an Opposite Role in Mice Brain Aging.

Science.gov (United States)

Castrogiovanni, Paola; Li Volti, Giovanni; Sanfilippo, Cristina; Tibullo, Daniele; Galvano, Fabio; Vecchio, Michele; Avola, Roberto; Barbagallo, Ignazio; Malaguarnera, Lucia; Castorina, Sergio; Musumeci, Giuseppe; Imbesi, Rosa; Di Rosa, Michelino

2018-01-20

Fasting may be exploited as a possible strategy for prevention and treatment of several diseases such as diabetes, obesity, and aging. On the other hand, high-fat diet (HFD) represents a risk factor for several diseases and increased mortality. The aim of the present study was to evaluate the impact of fasting on mouse brain aging transcriptome and how HFD regulates such pathways. We used the NCBI Gene Expression Omnibus (GEO) database, in order to identify suitable microarray datasets comparing mouse brain transcriptome under fasting or HFD vs aged mouse brain transcriptome. Three microarray datasets were selected for this study, GSE24504, GSE6285, and GSE8150, and the principal molecular mechanisms involved in this process were evaluated. This analysis showed that, regardless of fasting duration, mouse brain significantly expressed 21 and 30 upregulated and downregulated genes, respectively. The involved biological processes were related to cell cycle arrest, cell death inhibition, and regulation of cellular metabolism. Comparing mouse brain transcriptome under fasting and aged conditions, we found out that the number of genes in common increased with the duration of fasting (222 genes), peaking at 72 h. In addition, mouse brain transcriptome under HFD resembles for the 30% the one of the aged mice. Furthermore, several molecular processes were found to be shared between HFD and aging. In conclusion, we suggest that fasting and HFD play an opposite role in brain transcriptome of aged mice. Therefore, an intermittent diet could represent a possible clinical strategy to counteract aging, loss of memory, and neuroinflammation. Furthermore, low-fat diet leads to the inactivation of brain degenerative processes triggered by aging.

Cosmetics-triggered percutaneous remote control of transgene expression in mice.

Science.gov (United States)

Wang, Hui; Ye, Haifeng; Xie, Mingqi; Daoud El-Baba, Marie; Fussenegger, Martin

2015-08-18

Synthetic biology has significantly advanced the rational design of trigger-inducible gene switches that program cellular behavior in a reliable and predictable manner. Capitalizing on genetic componentry, including the repressor PmeR and its cognate operator OPmeR, that has evolved in Pseudomonas syringae pathovar tomato DC3000 to sense and resist plant-defence metabolites of the paraben class, we have designed a set of inducible and repressible mammalian transcription-control devices that could dose-dependently fine-tune transgene expression in mammalian cells and mice in response to paraben derivatives. With an over 60-years track record as licensed preservatives in the cosmetics industry, paraben derivatives have become a commonplace ingredient of most skin-care products including shower gels, cleansing toners and hand creams. As parabens can rapidly reach the bloodstream of mice following topical application, we used this feature to percutaneously program transgene expression of subcutaneous designer cell implants using off-the-shelf commercial paraben-containing skin-care cosmetics. The combination of non-invasive, transdermal and orthogonal trigger-inducible remote control of transgene expression may provide novel opportunities for dynamic interventions in future gene and cell-based therapies. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Impaired immune responses in the lungs of aged mice following influenza infection

Directory of Open Access Journals (Sweden)

Toapanta Franklin R

2009-11-01

Full Text Available Abstract Background Each year, influenza virus infection causes severe morbidity and mortality, particularly in the most susceptible groups including children, the elderly (>65 years-old and people with chronic respiratory diseases. Among the several factors that contribute to the increased susceptibility in elderly populations are the higher prevalence of chronic diseases (e.g. diabetes and the senescence of the immune system. Methods In this study, aged and adult mice were infected with sublethal doses of influenza virus (A/Puerto Rico/8/1934. Differences in weight loss, morbidity, virus titer and the kinetics of lung infiltration with cells of the innate and adaptive immune responses were analyzed. Additionally, the main cytokines and chemokines produced by these cells were also assayed. Results Compared to adult mice, aged mice had higher morbidity, lost weight more rapidly, and recovered more slowly from infection. There was a delay in the accumulation of granulocytic cells and conventional dendritic cells (cDCs, but not macrophages in the lungs of aged mice compared to adult animals. The delayed infiltration kinetics of APCs in aged animals correlated with alteration in their activation (CD40 expression, which also correlated with a delayed detection of cytokines and chemokines in lung homogenates. This was associated with retarded lung infiltration by natural killer (NK, CD4+ and CD8+ T-cells. Furthermore, the percentage of activated (CD69+ influenza-specific and IL-2 producer CD8+ T-cells was higher in adult mice compared to aged ones. Additionally, activation (CD69+ of adult B-cells was earlier and correlated with a quicker development of neutralizing antibodies in adult animals. Conclusion Overall, alterations in APC priming and activation lead to delayed production of cytokines and chemokines in the lungs that ultimately affected the infiltration of immune cells following influenza infection. This resulted in delayed activation of the

Every-other-day feeding extends lifespan but fails to delay many symptoms of aging in mice.

Science.gov (United States)

Xie, Kan; Neff, Frauke; Markert, Astrid; Rozman, Jan; Aguilar-Pimentel, Juan Antonio; Amarie, Oana Veronica; Becker, Lore; Brommage, Robert; Garrett, Lillian; Henzel, Kristin S; Hölter, Sabine M; Janik, Dirk; Lehmann, Isabelle; Moreth, Kristin; Pearson, Brandon L; Racz, Ildiko; Rathkolb, Birgit; Ryan, Devon P; Schröder, Susanne; Treise, Irina; Bekeredjian, Raffi; Busch, Dirk H; Graw, Jochen; Ehninger, Gerhard; Klingenspor, Martin; Klopstock, Thomas; Ollert, Markus; Sandholzer, Michael; Schmidt-Weber, Carsten; Weiergräber, Marco; Wolf, Eckhard; Wurst, Wolfgang; Zimmer, Andreas; Gailus-Durner, Valerie; Fuchs, Helmut; Hrabě de Angelis, Martin; Ehninger, Dan

2017-07-24

Dietary restriction regimes extend lifespan in various animal models. Here we show that longevity in male C57BL/6J mice subjected to every-other-day feeding is associated with a delayed onset of neoplastic disease that naturally limits lifespan in these animals. We compare more than 200 phenotypes in over 20 tissues in aged animals fed with a lifelong every-other-day feeding or ad libitum access to food diet to determine whether molecular, cellular, physiological and histopathological aging features develop more slowly in every-other-day feeding mice than in controls. We also analyze the effects of every-other-day feeding on young mice on shorter-term every-other-day feeding or ad libitum to account for possible aging-independent restriction effects. Our large-scale analysis reveals overall only limited evidence for a retardation of the aging rate in every-other-day feeding mice. The data indicate that every-other-day feeding-induced longevity is sufficiently explained by delays in life-limiting neoplastic disorders and is not associated with a more general slowing of the aging process in mice.Dietary restriction can extend the life of various model organisms. Here, Xie et al. show that intermittent periods of fasting achieved through every-other-day feeding protect mice against neoplastic disease but do not broadly delay organismal aging in animals.

Transgenic mice expressing mutant Pinin exhibit muscular dystrophy, nebulin deficiency and elevated expression of slow-type muscle fiber genes

International Nuclear Information System (INIS)

Wu, Hsu-Pin; Hsu, Shu-Yuan; Wu, Wen-Ai; Hu, Ji-Wei; Ouyang, Pin

2014-01-01

Highlights: •Pnn CCD domain functions as a dominant negative mutant regulating Pnn expression and function. •Pnn CCD mutant Tg mice have a muscle wasting phenotype during development and show dystrophic histological features. •Pnn mutant muscles are susceptible to slow fiber type gene transition and NEB reduction. •The Tg mouse generated by overexpression of the Pnn CCD domain displays many characteristics resembling NEB +/− mice. -- Abstract: Pinin (Pnn) is a nuclear speckle-associated SR-like protein. The N-terminal region of the Pnn protein sequence is highly conserved from mammals to insects, but the C-terminal RS domain-containing region is absent in lower species. The N-terminal coiled-coil domain (CCD) is, therefore, of interest not only from a functional point of view, but also from an evolutionarily standpoint. To explore the biological role of the Pnn CCD in a physiological context, we generated transgenic mice overexpressing Pnn mutant in skeletal muscle. We found that overexpression of the CCD reduces endogenous Pnn expression in cultured cell lines as well as in transgenic skeletal muscle fibers. Pnn mutant mice exhibited reduced body mass and impaired muscle function during development. Mutant skeletal muscles show dystrophic histological features with muscle fibers heavily loaded with centrally located myonuclei. Expression profiling and pathway analysis identified over-representation of genes in gene categories associated with muscle contraction, specifically those related to slow type fiber. In addition nebulin (NEB) expression level is repressed in Pnn mutant skeletal muscle. We conclude that Pnn downregulation in skeletal muscle causes a muscular dystrophic phenotype associated with NEB deficiency and the CCD domain is incapable of replacing full length Pnn in terms of functional capacity

Transgenic mice expressing mutant Pinin exhibit muscular dystrophy, nebulin deficiency and elevated expression of slow-type muscle fiber genes

Energy Technology Data Exchange (ETDEWEB)

Wu, Hsu-Pin; Hsu, Shu-Yuan [Department of Anatomy, Chang Gung University Medical College, Taiwan (China); Wu, Wen-Ai; Hu, Ji-Wei [Transgenic Mouse Core Laboratory, Chang Gung University, Taiwan (China); Ouyang, Pin, E-mail: ouyang@mail.cgu.edu.tw [Department of Anatomy, Chang Gung University Medical College, Taiwan (China); Transgenic Mouse Core Laboratory, Chang Gung University, Taiwan (China); Molecular Medicine Research Center, Chang Gung University, Taiwan (China)

2014-01-03

Highlights: •Pnn CCD domain functions as a dominant negative mutant regulating Pnn expression and function. •Pnn CCD mutant Tg mice have a muscle wasting phenotype during development and show dystrophic histological features. •Pnn mutant muscles are susceptible to slow fiber type gene transition and NEB reduction. •The Tg mouse generated by overexpression of the Pnn CCD domain displays many characteristics resembling NEB{sup +/−} mice. -- Abstract: Pinin (Pnn) is a nuclear speckle-associated SR-like protein. The N-terminal region of the Pnn protein sequence is highly conserved from mammals to insects, but the C-terminal RS domain-containing region is absent in lower species. The N-terminal coiled-coil domain (CCD) is, therefore, of interest not only from a functional point of view, but also from an evolutionarily standpoint. To explore the biological role of the Pnn CCD in a physiological context, we generated transgenic mice overexpressing Pnn mutant in skeletal muscle. We found that overexpression of the CCD reduces endogenous Pnn expression in cultured cell lines as well as in transgenic skeletal muscle fibers. Pnn mutant mice exhibited reduced body mass and impaired muscle function during development. Mutant skeletal muscles show dystrophic histological features with muscle fibers heavily loaded with centrally located myonuclei. Expression profiling and pathway analysis identified over-representation of genes in gene categories associated with muscle contraction, specifically those related to slow type fiber. In addition nebulin (NEB) expression level is repressed in Pnn mutant skeletal muscle. We conclude that Pnn downregulation in skeletal muscle causes a muscular dystrophic phenotype associated with NEB deficiency and the CCD domain is incapable of replacing full length Pnn in terms of functional capacity.

Analysis of mice radiosensitivity depending on age

International Nuclear Information System (INIS)

Bogatyrev, A.V.; Timoshenko, S.I.; Nikanorova, N.G.; Sverdlov, A.G.

1979-01-01

In order to elucidate mechanisms of age variations in radiosensitivity of mice a study was made of the sensitivity of in vitro irradiated bone marrow stem cells, taken from animals of different age, and postradiation recovery of leukocyte content of peripheral blood and cellularity of bone marrow and spleen. Using the method of spleen colonies similar affections were revealed in bone marrow cells of animals of different age. The degree of recovery of the hemopoietic cell pool was significantly lower in newborn mice than in adults after exposure to a dose (LDsub(50/30)) equally effective with respect to mortality

Salt-Sensitive Hypertension and Cardiac Hypertrophy in Transgenic Mice Expressing a Corin Variant Identified in African Americans

Science.gov (United States)

Wang, Wei; Cui, Yujie; Shen, Jianzhong; Jiang, Jingjing; Chen, Shenghan; Peng, Jianhao; Wu, Qingyu

2012-01-01

African Americans represent a high risk population for salt-sensitive hypertension and heart disease but the underlying mechanism remains unclear. Corin is a cardiac protease that regulates blood pressure by activating natriuretic peptides. A corin gene variant (T555I/Q568P) was identified in African Americans with hypertension and cardiac hypertrophy. In this study, we test the hypothesis that the corin variant contributes to the hypertensive and cardiac hypertrophic phenotype in vivo. Transgenic mice were generated to express wild-type or T555I/Q568P variant corin in the heart under the control of α-myosin heavy chain promoter. The mice were crossed into a corin knockout background to create KO/TgWT and KO/TgV mice that expressed WT or variant corin, respectively, in the heart. Functional studies showed that KO/TgV mice had significantly higher levels of pro-atrial natriuretic peptide in the heart compared with that in control KO/TgWT mice, indicating that the corin variant was defective in processing natriuretic peptides in vivo. By radiotelemetry, corin KO/TgV mice were found to have hypertension that was sensitive to dietary salt loading. The mice also developed cardiac hypertrophy at 12–14 months of age when fed a normal salt diet or at a younger age when fed a high salt diet. The phenotype of salt-sensitive hypertension and cardiac hypertrophy in KO/TgV mice closely resembles the pathological findings in African Americans who carry the corin variant. The results indicate that corin defects may represent an important mechanism in salt-sensitive hypertension and cardiac hypertrophy in African Americans. PMID:22987923

Gene expression of drug metabolizing enzymes in adult and aged mouse liver: A modulation by immobilization stress

International Nuclear Information System (INIS)

Mikhailova, O.N.; Gulyaeva, L.F.; Filipenko, M.L.

2005-01-01

The role of stress in the regulation of enzymatic systems involved in the biotransformation of xenobiotics, as well as endogenous substrates in the liver was investigated using single immobilization stress as a model. Adult (3 months of age) and aged (26 months) C3H/a male mice were used. Cytochrome P450 1A1 and 1A2 (CYP1A1 and CYP1A2), glutathione S-transferase M1 (GSTM1), aryl hydrocarbon receptor (AHR), aryl hydrocarbon receptor nuclear translocator (ARNT) and catechol-O-methyltransferase (COMT) mRNA levels in the mouse liver were measured by a semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) method. Excluding CYP1A1, experiments revealed significant differences in the expression of these genes between adult- and aged-control animals. The influence of stress on the expression of genes studied was shown to be higher in adult mice than in aged ones. Our results clearly demonstrate the lack of response or even the attenuation of gene expression in aged animals that may play an important role in age-related pathologies and diseases

Beta-Amyloid Downregulates MDR1-P-Glycoprotein (Abcb1 Expression at the Blood-Brain Barrier in Mice

Directory of Open Access Journals (Sweden)

Anja Brenn

2011-01-01

Full Text Available Neurovascular dysfunction is an important component of Alzheimer's disease, leading to reduced clearance across the blood-brain barrier and accumulation of neurotoxic β-amyloid (Aβ peptides in the brain. It has been shown that the ABC transport protein P-glycoprotein (P-gp, ABCB1 is involved in the export of Aβ from the brain into the blood. To determine whether Aβ influences the expression of key Aβ transporters, we studied the effects of 1-day subcutaneous Aβ1-40 and Aβ1-42 administration via Alzet mini-osmotic pumps on P-gp, BCRP, LRP1, and RAGE expression in the brain of 90-day-old male FVB mice. Our results demonstrate significantly reduced P-gp, LRP1, and RAGE mRNA expression in mice treated with Aβ1-42 compared to controls, while BCRP expression was not affected. The expression of the four proteins was unchanged in mice treated with Aβ1-40 or reverse-sequence peptides. These findings indicate that, in addition to the age-related decrease of P-gp expression, Aβ1-42 itself downregulates the expression of P-gp and other Aβ-transporters, which could exacerbate the intracerebral accumulation of Aβ and thereby accelerate neurodegeneration in Alzheimer's disease and cerebral β-amyloid angiopathy.

Over-expressing the soluble gp130-Fc does not ameliorate methionine and choline deficient diet-induced non alcoholic steatohepatitis in mice.

Directory of Open Access Journals (Sweden)

Helene L Kammoun

Full Text Available Non-alcoholic steatohepatitis (NASH is a liver disease with the potential to lead to cirrhosis and hepatocellular carcinoma. Interleukin-6 (IL-6 has been implicated in the pathogenesis of NASH, with the so-called IL-6 'trans-signaling' cascade being responsible for the pro-inflammatory actions of this cytokine. We aimed to block IL-6 'trans-signaling', using a transgenic mouse that overexpresses human soluble glycoprotein130 (sgp130Fc Tg mice fed a commonly used dietary model of inducing NASH (methionine and choline deficient-diet; MCD diet and hypothesized that markers of NASH would be ameliorated in such mice. Sgp130Fc Tg and littermate control mice were fed a MCD or control diet for 4 weeks. The MCD diet induced many hallmarks of NASH including hepatomegaly, steatosis, and liver inflammation. However, in contrast with other mouse models and, indeed, human NASH, the MCD diet model did not increase the mRNA or protein expression of IL-6. Not surprisingly, therefore, markers of MCD diet-induced NASH were unaffected by sgp130Fc transgenic expression. While the MCD diet model induces many pathophysiological markers of NASH, it does not induce increased IL-6 expression in the liver, a key hallmark of human NASH. We, therefore, caution the use of the MCD diet as a viable mouse model of NASH.

Aging has small effects on initial ischemic acute kidney injury development despite changing intrarenal immunologic micromilieu in mice.

Science.gov (United States)

Jang, Hye Ryoun; Park, Ji Hyeon; Kwon, Ghee Young; Park, Jae Berm; Lee, Jung Eun; Kim, Dae Joong; Kim, Yoon-Goo; Kim, Sung Joo; Oh, Ha Young; Huh, Wooseong

2016-02-15

Inflammatory process mediated by innate and adaptive immune systems is a major pathogenic mechanism of renal ischemia-reperfusion injury (IRI). There are concerns that organ recipients may be at increased risk of developing IRI after receiving kidneys from elder donors. To reveal the effects of aging on the development of renal IRI, we compared the immunologic micromilieu of normal and postischemic kidneys from mice of three different ages (9 wk, 6 mo, and 12 mo). There was a higher number of total T cells, especially effector memory CD4/CD8 T cells, and regulatory T cells in the normal kidneys of old mice. On day 2 after IRI, the proportion of necrotic tubules and renal functional changes were comparable between groups although old mice had a higher proportion of damaged tubule compared with young mice. More T cells, but less B cells, trafficked into the postischemic kidneys of old mice. The infiltration of NK T cells was similar across the groups. Macrophages and neutrophils were comparable between groups in both normal kidneys and postischemic kidneys. The intrarenal expressions of TNF-α and VEGF were decreased in normal and postischemic kidneys of aged mice. These mixed effects of aging on lymphocytes and cytokines/chemokines were not different between the two groups of old mice. Our study demonstrates that aging alters the intrarenal micromilieu but has small effects on the development of initial renal injury after IRI. Further study investigating aging-dependent differences in the repair process of renal IRI may be required. Copyright © 2016 the American Physiological Society.

Transgenic mice overexpressing glia maturation factor-β, an oxidative stress inducible gene, show premature aging due to Zmpste24 down-regulation.

Science.gov (United States)

Imai, Rika; Asai, Kanae; Hanai, Jun-ichi; Takenaka, Masaru

2015-07-01

Glia Maturation Factor-β (GMF), a brain specific protein, is induced by proteinuria in renal tubules. Ectopic GMF overexpression causes apoptosisin vitro via cellular vulnerability to oxidative stress. In order to examine the roles of GMF in non-brain tissue, we constructed transgenic mice overexpressing GMF (GMF-TG). The GMF-TG mice exhibited appearance phenotypes associated with premature aging. The GMF-TG mice also demonstrated short lifespans and reduced hair regrowth, suggesting an accelerated aging process. The production of an abnormal lamin A, a nuclear envelope protein, plays a causal role in both normal aging and accelerated aging diseases, known as laminopathies. Importantly, we identified the abnormal lamin A (prelamin A), accompanied by a down-regulation of a lamin A processing enzyme (Zmpste24) in the kidney of the GMF-TG mice. The GMF-TG mice showed accelerated aging in the kidney, compared with wild-type mice, showing increased TGF-β1, CTGF gene and serum creatinine. The gene expression of p21/waf1 was increased at an earlier stage of life, at 10 weeks, which was in turn down-regulated at a later stage, at 60 weeks. In conclusion, we propose that GMF-TG mice might be a novel mouse model of accelerated aging, due to the abnormal lamin A.

Running rescues a fear-based contextual discrimination deficit in aged mice

Directory of Open Access Journals (Sweden)

Melody V. Wu

2015-08-01

Full Text Available Normal aging and exercise exert extensive, often opposing, effects on the dentate gyrus (DG of the hippocampus altering volume, synaptic function, and behaviors. The DG is especially important for behaviors requiring pattern separation—a cognitive process that enables animals to differentiate between highly similar contextual experiences. To determine how age and exercise modulate pattern separation in an aversive setting, young, aged, and aged mice provided with a running wheel were assayed on a fear-based contextual discrimination task. Aged mice showed a profound impairment in contextual discrimination compared to young animals. Voluntary exercise rescued this deficit to such an extent that behavioral pattern separation of aged-run mice was now similar to young animals. Running also resulted in a significant increase in the number of immature neurons with tertiary dendrites in aged mice. Despite this, neurogenesis levels in aged-run mice were still considerably lower than in young animals. Thus, mechanisms other than DG neurogenesis likely play significant roles in improving behavioral pattern separation elicited by exercise in aged animals.

Cellular oncogene expression following exposure of mice to γ-rays

International Nuclear Information System (INIS)

Anderson, A.; Woloschak, G.E.

1991-01-01

We examined the effects of total body exposure of BCF1 mice to γ-rays (300 cGy) in modulating expression of cellular oncogenes in both gut and liver tissues. We selected specific cellular oncogenes (c-fos, c-myc, c-src, and c-H-ras), based on their normal expression in liver and gut tissues from untreated mice. As early as 5 min. following whole body exposure of BCF1 mice to γ-rays we detected induction of mRNA specific for c-src and c-H-ras in both liver and gut tissues. c-fos RNA was slightly decreased in accumulation in gut but was unaffected in liver tissue from irradiated mice relative to untreated controls. c-myc mRNA accumulation was unaffected in all tissues examined. These experiments document that modulation of cellular oncogene expression can occur as an early event in tissues following irradiation and suggest that this modulation may play a role in radiation-induced carcinogenesis

Alterations in expression of Cat-315 epitope of perineuronal nets during normal ageing, and its modulation by an open-channel NMDA receptor blocker, memantine.

Science.gov (United States)

Yamada, Jun; Ohgomori, Tomohiro; Jinno, Shozo

2017-06-15

The perineuronal net (PNN), a specialized aggregate of the extracellular matrix, is involved in neuroprotection against oxidative stress, which is now recognized as a major contributor to age-related decline in brain functions. In this study, we investigated the age-related molecular changes of PNNs using monoclonal antibody Cat-315, which recognizes human natural killer-1 (HNK-1) glycan on aggrecan-based PNNs. Western blot analysis showed that the expression levels of Cat-315 epitope in the hippocampus were higher in middle-aged (MA, 12-month-old) mice than in young adult (YA, 2-month-old) mice. Although there were no differences in the expression levels of Cat-315 epitope between old age (OA, 20-month-old) and MA mice, Cat-315 immunoreactivity was also detected in astrocytes of OA mice. To focus on Cat-315 epitope in PNNs, we used YA and MA mice in the following experiments. Optical disector analysis showed that there were no differences in the numbers of Cat-315-positive (Cat-315 + ) PNNs between YA and MA mice. Fluorescence intensity analysis indicated that Cat-315 immunoreactivity in PNNs increased with age in the dorsal hippocampus, which is mainly involved in cognitive functions. Administration of an open-channel blocker of NMDA receptor, memantine, reduced the expression levels of Cat-315 epitope in the hippocampus. Furthermore, the numbers of glutamatergic and GABAergic terminals colocalized with Cat-315 epitope around parvalbumin-positive neurons were decreased by memantine. These findings provide novel insight into the involvement of PNNs in normal brain ageing, and suggest that memantine may counteract the age-related alterations in expression levels of Cat-315 epitope via regulation of its subcellular localization. © 2017 Wiley Periodicals, Inc.

Relationship between aquaporin-5 expression and saliva flow in streptozotocin-induced diabetic mice?

Science.gov (United States)

Soyfoo, M S; Bolaky, N; Depoortere, I; Delporte, C

2012-07-01

To investigate the expression and distribution of AQP5 in submandibular acinar cells from sham- and streptozotocin (STZ)-treated mice in relation to the salivary flow. Mice were sham or STZ injected. Distribution of AQP5 subcellular expression in submandibular glands was determined by immunohistochemistry. AQP5 labelling indices (LI), reflecting AQP5 subcellular distribution, were determined in acinar cells. Western blotting was performed to determine the expression of AQP5 in submandibular glands. Blood glycaemia and osmolality and saliva flow rates were also determined. AQP5 immunoreactivity was primarily located at the apical and apical-basolateral membranes of submandibular gland acinar cells from sham- and STZ-treated mice. No significant differences in AQP5 protein levels were observed between sham- and STZ-treated mice. Compared to sham-treated mice, STZ-treated mice had significant increased glycaemia, while no significant differences in blood osmolality were observed. Saliva flow rate was significantly decreased in STZ-treated mice as compared to sham-treated mice. In STZ-treated mice, significant reduction in salivary flow rate was observed without any concomitant modification in AQP5 expression and localization. © 2011 John Wiley & Sons A/S.

Gene expression changes for antioxidants pathways in the mouse cochlea: relations to age-related hearing deficits.

Directory of Open Access Journals (Sweden)

Sherif F Tadros

Full Text Available Age-related hearing loss - presbycusis - is the number one neurodegenerative disorder and top communication deficit of our aged population. Like many aging disorders of the nervous system, damage from free radicals linked to production of reactive oxygen and/or nitrogen species (ROS and RNS, respectively may play key roles in disease progression. The efficacy of the antioxidant systems, e.g., glutathione and thioredoxin, is an important factor in pathophysiology of the aging nervous system. In this investigation, relations between the expression of antioxidant-related genes in the auditory portion of the inner ear - cochlea, and age-related hearing loss was explored for CBA/CaJ mice. Forty mice were classified into four groups according to age and degree of hearing loss. Cochlear mRNA samples were collected and cDNA generated. Using Affymetrix® GeneChip, the expressions of 56 antioxidant-related gene probes were analyzed to estimate the differences in gene expression between the four subject groups. The expression of Glutathione peroxidase 6, Gpx6; Thioredoxin reductase 1, Txnrd1; Isocitrate dehydrogenase 1, Idh1; and Heat shock protein 1, Hspb1; were significantly different, or showed large fold-change differences between subject groups. The Gpx6, Txnrd1 and Hspb1 gene expression changes were validated using qPCR. The Gpx6 gene was upregulated while the Txnrd1 gene was downregulated with age/hearing loss. The Hspb1 gene was found to be downregulated in middle-aged animals as well as those with mild presbycusis, whereas it was upregulated in those with severe presbycusis. These results facilitate development of future interventions to predict, prevent or slow down the progression of presbycusis.

The anti-hypercholesterolemic effect of low p53 expression protects vascular endothelial function in mice.

Directory of Open Access Journals (Sweden)

Francois Leblond

Full Text Available To demonstrate that p53 modulates endothelial function and the stress response to a high-fat western diet (WD.Three-month old p53+/+ wild type (WT and p53+/- male mice were fed a regular or WD for 3 months. Plasma levels of total cholesterol (TC and LDL-cholesterol were significantly elevated (p<0.05 in WD-fed WT (from 2.1±0.2 mmol/L to 3.1±0.2, and from 0.64±0.09 mmol/L to 1.25±0.11, respectively but not in p53+/- mice. The lack of cholesterol accumulation in WD-fed p53+/- mice was associated with high bile acid plasma concentrations (p53+/- =  4.7±0.9 vs. WT =  3.3±0.2 μmol/L, p<0.05 concomitant with an increased hepatic 7-alpha-hydroxylase mRNA expression. While the WD did not affect aortic endothelial relaxant function in p53+/- mice (WD =  83±5 and RD =  82±4% relaxation, it increased the maximal response to acetylcholine in WT mice (WD =  87±2 vs. RD =  62±5% relaxation, p<0.05 to levels of p53+/-. In WT mice, the rise in TC associated with higher (p<0.05 plasma levels of pro-inflammatory keratinocyte-derived chemokine, and an over-activation (p<0.05 of the relaxant non-nitric oxide/non-prostacyclin endothelial pathway. It is likely that in WT mice, activations of these pathways are adaptive and contributed to maintain endothelial function, while the WD neither promoted inflammation nor affected endothelial function in p53+/- mice.Our data demonstrate that low endogenous p53 expression prevents the rise in circulating levels of cholesterol when fed a WD. Consequently, the endothelial stress of hypercholesterolemia is absent in young p53+/- mice as evidenced by the absence of endothelial adaptive pathway over-activation to minimize stress-related damage.

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.

Age-Related Hearing Loss in Mn-SOD Heterozygous Knockout Mice

Directory of Open Access Journals (Sweden)

Makoto Kinoshita

2013-01-01

Full Text Available Age-related hearing loss (AHL reduces the quality of life for many elderly individuals. Manganese superoxide dismutase (Mn-SOD, one of the antioxidant enzymes acting within the mitochondria, plays a crucial role in scavenging reactive oxygen species (ROS. To determine whether reduction in Mn-SOD accelerates AHL, we evaluated auditory function in Mn-SOD heterozygous knockout (HET mice and their littermate wild-type (WT C57BL/6 mice by means of auditory brainstem response (ABR. Mean ABR thresholds were significantly increased at 16 months when compared to those at 4 months in both WT and HET mice, but they did not significantly differ between them at either age. The extent of hair cell loss, spiral ganglion cell density, and thickness of the stria vascularis also did not differ between WT and HET mice at either age. At 16 months, immunoreactivity of 8-hydroxydeoxyguanosine was significantly greater in the SGC and SV in HET mice compared to WT mice, but that of 4-hydroxynonenal did not differ between them. These findings suggest that, although decrease of Mn-SOD by half may increase oxidative stress in the cochlea to some extent, it may not be sufficient to accelerate age-related cochlear damage under physiological aging process.

The mRNA expression of XRCC repair genes in mice after γ-ray radiation

International Nuclear Information System (INIS)

Wang Qin; Yue Jingyin; Li Jin; Mu Chuanjie; Fan Feiyue

2006-01-01

Objective: To investigate the role of XRCC repair genes in radioresistance of IRM-2 inbred mice. Methods: Northern hybridization was used to measure mRNA expression of XRCC1 and XRCC5 genes in IRM-2 inbred mice. ICR/JCL and 615 after exposure to different doses of γ-ray radiation at different postirradiation time. Results: The levels of XRCC1 and XRCC5 mRNA expression in control IRM-2 mice were higher significantly than those in their control parental mice (P<0.01 and P<0.05). The mRNA expression of XRCC genes in ICR/JCL and 615 mice all increased to some extent after exposure 1, 2 and 4 Gy radiation. But the levels were significantly higher at 2h postirradiation (P<0.05) . The levels of XRCC mRNA expression in IRM-2 mice did not increase significnatly compared with the control mice after exposure 1 and 2 Gy radiation. But the levels of XRCC1 and XRCC5 mRNA expression increased markedly at 4Gy 1h postirradiation (P<0.05 and P<0.01). Conclusion: The basal levels of XRCC1 and XRCC5 mRNA expression in IRM-2 mice were high. The high level of XRCC5 mRNA expression was involved in the repair of DNA double strand breaks induced by higher dose radiation, which perhaps was one of radioresistance causes of IRM-2 mice. (authors)

Skeletal muscles of aged male mice fail to adapt following contractile activity.

Science.gov (United States)

Vasilaki, A; Iwanejko, L M; McArdle, F; Broome, C S; Jackson, M J; McArdle, A

2003-04-01

Skeletal muscle adapts rapidly following exercise by the increased production of heat-shock proteins (HSPs). The aim of this study was to examine the ability of muscle from adult and aged mice to produce HSPs following non-damaging exercise. Adult and aged B6XSJL mice were anaesthetized and their hind limbs were subjected to isometric contractions. At different time points, muscles were analysed for HSP production by Western and Northern blotting and by electrophoretic mobility-shift assay. HSP protein and mRNA levels in muscles from adult mice increased significantly following exercise. This was not evident in muscles of aged mice. In contrast, binding of the transcription factor heat-shock factor 1 (HSF1) was not grossly altered in muscles of aged mice compared with adult mice. The data suggest that the inability of muscles of aged mice to produce HSPs appears to be due to alterations during gene transcription.

Aging exacerbates depressive-like behavior in mice in response to activation of the peripheral innate immune system.

Science.gov (United States)

Godbout, Jonathan P; Moreau, Maïté; Lestage, Jacques; Chen, Jing; Sparkman, Nathan L; O'Connor, Jason; Castanon, Nathalie; Kelley, Keith W; Dantzer, Robert; Johnson, Rodney W

2008-09-01

Exposure to peripheral infections may be permissive to cognitive and behavioral complications in the elderly. We have reported that peripheral stimulation of the innate immune system with lipopolysaccharide (LPS) causes an exaggerated neuroinflammatory response and prolonged sickness behavior in aged BALB/c mice. Because LPS also causes depressive behavior, the purpose of this study was to determine whether aging is associated with an exacerbated depressive-like response. We confirmed that LPS (0.33 mg/kg intraperitoneal) induced a protracted sickness response in aged mice with reductions in locomotor and feeding activities 24 and 48 h postinjection, when young adults had fully recovered. When submitted to the forced swim test 24 h post-LPS, both young adult and aged mice exhibited an increased duration of immobility. However, when submitted to either the forced swim test or the tail suspension test 72 h post-LPS, an increased duration of immobility was evident only in aged mice. This prolonged depressive-like behavior in aged LPS-treated mice was associated with a more pronounced induction of peripheral and brain indoleamine 2,3-dioxygenase and a markedly higher turnover rate of brain serotonin (as measured by the ratio of 5-hydroxy-indoleacetic acid over 5-hydroxy-tryptamine) compared to young adult mice at 24 post-LPS injection. These results provide the first evidence that age-associated reactivity of the brain cytokine system could play a pathophysiological role in the increased prevalence of depression observed in the elderly.

Serotonin 5-HT2C receptor-independent expression of hypothalamic NOR1, a novel modulator of food intake and energy balance, in mice

International Nuclear Information System (INIS)

Nonogaki, Katsunori; Kaji, Takao; Ohba, Yukie; Sumii, Makiko; Wakameda, Mamoru; Tamari, Tomohiro

2009-01-01

NOR1, Nur77 and Nurr1 are orphan nuclear receptors and members of the NR4A subfamily. Here, we report that the expression of hypothalamic NOR1 was remarkably decreased in mildly obese β-endorphin-deficient mice and obese db/db mice with the leptin receptor mutation, compared with age-matched wild-type mice, whereas there were no genotypic differences in the expression of hypothalamic Nur77 or Nurr1 in these animals. The injection of NOR1 siRNA oligonucleotide into the third cerebral ventricle significantly suppressed food intake and body weight in mice. On the other hand, the decreases in hypothalamic NOR1 expression were not found in non-obese 5-HT2C receptor-deficient mice. Moreover, systemic administration of m-chlorophenylpiperazine (mCPP), a 5-HT2C/1B receptor agonist, had no effect on hypothalamic NOR1 expression, while suppressing food intake in β-endorphin-deficient mice. These findings suggest that 5-HT2C receptor-independent proopiomelanocortin-derived peptides regulate the expression of hypothalamic NOR1, which is a novel modulator of feeding behavior and energy balance.

Serotonin 5-HT2C receptor-independent expression of hypothalamic NOR1, a novel modulator of food intake and energy balance, in mice

Energy Technology Data Exchange (ETDEWEB)

Nonogaki, Katsunori, E-mail: knonogaki-tky@umin.ac.jp [Center of Excellence, Division of Molecular Metabolism and Diabetes, Tohoku University Graduate School of Medicine (Japan); Department of Lifestyle Medicine, Biomedical Engineering Center, Tohoku University (Japan); Kaji, Takao [Department of Lifestyle Medicine, Biomedical Engineering Center, Tohoku University (Japan); Ohba, Yukie; Sumii, Makiko [Center of Excellence, Division of Molecular Metabolism and Diabetes, Tohoku University Graduate School of Medicine (Japan); Wakameda, Mamoru; Tamari, Tomohiro [Charles River Laboratories Japan, Inc. (Japan)

2009-08-21

NOR1, Nur77 and Nurr1 are orphan nuclear receptors and members of the NR4A subfamily. Here, we report that the expression of hypothalamic NOR1 was remarkably decreased in mildly obese {beta}-endorphin-deficient mice and obese db/db mice with the leptin receptor mutation, compared with age-matched wild-type mice, whereas there were no genotypic differences in the expression of hypothalamic Nur77 or Nurr1 in these animals. The injection of NOR1 siRNA oligonucleotide into the third cerebral ventricle significantly suppressed food intake and body weight in mice. On the other hand, the decreases in hypothalamic NOR1 expression were not found in non-obese 5-HT2C receptor-deficient mice. Moreover, systemic administration of m-chlorophenylpiperazine (mCPP), a 5-HT2C/1B receptor agonist, had no effect on hypothalamic NOR1 expression, while suppressing food intake in {beta}-endorphin-deficient mice. These findings suggest that 5-HT2C receptor-independent proopiomelanocortin-derived peptides regulate the expression of hypothalamic NOR1, which is a novel modulator of feeding behavior and energy balance.

SDF-1 alpha expression during wound healing in the aged is HIF dependent.

Science.gov (United States)

Loh, Shang A; Chang, Edward I; Galvez, Michael G; Thangarajah, Hariharan; El-ftesi, Samyra; Vial, Ivan N; Lin, Darius A; Gurtner, Geoffrey C

2009-02-01

Age-related impairments in wound healing are associated with decreased neovascularization, a process that is regulated by hypoxia-responsive cytokines, including stromal cell-derived factor (SDF)-1 alpha. Interleukin-1 beta is an important inflammatory cytokine involved in wound healing and is believed to regulate SDF-1 alpha expression independent of hypoxia signaling. Thus, the authors examined the relative importance of interleukin (IL)-1 beta and hypoxia-inducible factor (HIF)-1 alpha on SDF-1 alpha expression in aged wound healing. Young and aged mice (n = 4 per group) were examined for wound healing using a murine excisional wound model. Wounds were harvested at days 0, 1, 3, 5, and 7 for histologic analysis, immunohistochemistry, enzyme-linked immunosorbent assay, and Western blot. An engineered wild-type and mutated SDF luciferase reporter construct were used to determine HIF transactivation. Aged mice demonstrated significantly impaired wound healing, reduced granulation tissue, and increased epithelial gap compared with young controls. Real-time polymerase chain reaction demonstrated reduced SDF-1 alpha levels in aged wounds that correlated with reduced CD31+ neovessels. Western blots revealed decreased HIF-1 alpha protein in aged wounds. However, both IL-1 beta and macrophage infiltrate were unchanged between young and aged animals. Using the wild-type and mutated SDF luciferase reporter construct in which the hypoxia response element was deleted, only young fibroblasts were able to respond to IL-1 beta stimulation, and this response was abrogated by mutating the HIF-binding sites. This suggests that HIF binding is essential for SDF-1 transactivation in response to both inflammatory and hypoxic stimuli. SDF-1 alpha deficiency observed during aged wound healing is attributable predominantly to decreased HIF-1 alpha levels rather than impaired IL-1 beta expression.

Mucuna pruriens reduces inducible nitric oxide synthase expression in Parkinsonian mice model.

Science.gov (United States)

Yadav, Satyndra Kumar; Rai, Sachchida Nand; Singh, Surya Pratap

2017-03-01

Parkinson's disease is one of the most common neurodegenerative disease found in aged peoples. Plentiful studies are being conducted to find a suitable and effective cure for this disease giving special impetus on use of herbal plants. The study aimed at investigating the effect of ethanolic extract of Mucuna pruriens (Mp) on level of nitric oxide (NO) in paraquat (PQ) induced Parkinson's disease (PD) mouse model and its subsequent contribution to lipid peroxidation. Twenty four Swiss albino mice were divided into three groups; Control, PQ and PQ+Mp. PQ doses were given intraperitoneally, twice in a week and oral dose of ethanolic extract of Mp seed was given for 9 weeks. Nitrite content and lipid peroxidation was measured in all treated groups along with respective controls. RNA was isolated from the nigrostriatal tissue of control and the treated mice and was reverse transcribed into cDNA. PCR was performed to amplify iNOS mRNA and western blot analysis was performed to check its protein level. We had also perfused the mice in all treated group and performed Tyrosine hydroxylase (TH) and iNOS immunoreactivity in substantia nigra region of mice brain. PQ-treatment increased nitrite content, expression of iNOS and lipid peroxidation compared to respective controls. Mp treatment resulted in a significant attenuation of iNOS expression, nitrite content and lipid peroxidation demonstrating that it reduces nitric oxide in PQ-induced Parkinson's disease. Interestingly; we also observed that mRNA, protein expression and immunoreactivity of iNOS was significantly decreased after Mp treatment and TH immunoreactivity was significantly improved after the treatment of Mp. Our results demonstrated that Mp protects the dopaminergic neurons from the NO injury in substantia nigra. Copyright © 2016 Elsevier B.V. All rights reserved.

Meta-analysis of Gene Expression in the Mouse Liver Reveals Biomarkers Associated with Inflammation Increased Early During Aging

Science.gov (United States)

Aging is associated with a predictable loss of cellular homeostasis, a decline in physiological function and an increase in various diseases. We hypothesized that similar age-related gene expression profiles would be observed in mice across independent studies. Employing a metaan...

Profiling helper T cell subset gene expression in deer mice

Directory of Open Access Journals (Sweden)

Hjelle Brian

2006-08-01

Full Text Available Abstract Background Deer mice (Peromyscus maniculatus are the most common mammals in North America and are reservoirs for several zoonotic agents, including Sin Nombre virus (SNV, the principal etiologic agent of hantavirus cardiopulmonary syndrome (HCPS in North America. Unlike human HCPS patients, SNV-infected deer mice show no overt pathological symptoms, despite the presence of virus in the lungs. A neutralizing IgG antibody response occurs, but the virus establishes a persistent infection. Limitations of detailed analysis of deer mouse immune responses to SNV are the lack of reagents and methods for evaluating such responses. Results We developed real-time PCR-based detection assays for several immune-related transcription factor and cytokine genes from deer mice that permit the profiling of CD4+ helper T cells, including markers of Th1 cells (T-bet, STAT4, IFNγ, TNF, LT, Th2 cells (GATA-3, STAT6, IL-4, IL-5 and regulatory T cells (Fox-p3, IL-10, TGFβ1. These assays compare the expression of in vitro antigen-stimulated and unstimulated T cells from individual deer mice. Conclusion We developed molecular methods for profiling immune gene expression in deer mice, including a multiplexed real-time PCR assay for assessing expression of several cytokine and transcription factor genes. These assays should be useful for characterizing the immune responses of experimentally- and naturally-infected deer mice.

Opposing regulation of cytochrome P450 expression by CAR and PXR in hypothyroid mice

International Nuclear Information System (INIS)

Park, Young Joo; Lee, Eun Kyung; Lee, Yoon Kwang; Park, Do Joon; Jang, Hak Chul; Moore, David D.

2012-01-01

Clinical hypothyroidism affects various metabolic processes including drug metabolism. CYP2B and CYP3A are important cytochrome P450 drug metabolizing enzymes that are regulated by the xenobiotic receptors constitutive androstane receptor (CAR, NR1I3) and pregnane X receptor (PXR, NR1I2). We evaluated the regulation of the hepatic expression of CYPs by CAR and PXR in the hypothyroid state induced by a low-iodine diet containing 0.15% propylthiouracil. Expression of Cyp3a11 was suppressed in hypothyroid C57BL/6 wild type (WT) mice and a further decrement was observed in hypothyroid CAR −/− mice, but not in hypothyroid PXR −/− mice. In contrast, expression of Cyp2b10 was induced in both WT and PXR −/− hypothyroid mice, and this induction was abolished in CAR −/− mice and in and CAR −/− PXR −/− double knockouts. CAR mRNA expression was increased by hypothyroidism, while PXR expression remained unchanged. Carbamazepine (CBZ) is a commonly used antiepileptic that is metabolized by CYP3A isoforms. After CBZ treatment of normal chow fed mice, serum CBZ levels were highest in CAR −/− mice and lowest in WT and PXR −/− mice. Hypothyroid WT or PXR −/− mice survived chronic CBZ treatment, but all hypothyroid CAR −/− and CAR −/− PXR −/− mice died, with CAR −/− PXR −/− mice surviving longer than CAR −/− mice (12.3 ± 3.3 days vs. 6.3 ± 2.1 days, p = 0.04). All these findings suggest that hypothyroid status affects xenobiotic metabolism, with opposing responses of CAR and PXR and their CYP targets that can cancel each other out, decreasing serious metabolic derangement in response to a xenobiotic challenge. -- Highlights: ► Hypothyroid status activates CAR in mice and induces Cyp2b10 expression. ► Hypothyroid status suppresses PXR activity in mice and represses Cyp3a11 expression. ► These responses balance each other out in normal mice. ► Hypothyroidism sensitizes CAR null mice to toxic effects of carbamazepine.

Opposing regulation of cytochrome P450 expression by CAR and PXR in hypothyroid mice

Energy Technology Data Exchange (ETDEWEB)

Park, Young Joo [Department of Internal Medicine, Seoul National University College of Medicine (Korea, Republic of); Seoul National University Bundang Hospital, Seoul (Korea, Republic of); Lee, Eun Kyung [Department of Internal Medicine, Seoul National University College of Medicine (Korea, Republic of); Lee, Yoon Kwang [Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030 (United States); Park, Do Joon; Jang, Hak Chul [Department of Internal Medicine, Seoul National University College of Medicine (Korea, Republic of); Moore, David D., E-mail: moore@bcm.edu [Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030 (United States)

2012-09-01

Clinical hypothyroidism affects various metabolic processes including drug metabolism. CYP2B and CYP3A are important cytochrome P450 drug metabolizing enzymes that are regulated by the xenobiotic receptors constitutive androstane receptor (CAR, NR1I3) and pregnane X receptor (PXR, NR1I2). We evaluated the regulation of the hepatic expression of CYPs by CAR and PXR in the hypothyroid state induced by a low-iodine diet containing 0.15% propylthiouracil. Expression of Cyp3a11 was suppressed in hypothyroid C57BL/6 wild type (WT) mice and a further decrement was observed in hypothyroid CAR{sup −/−} mice, but not in hypothyroid PXR{sup −/−} mice. In contrast, expression of Cyp2b10 was induced in both WT and PXR{sup −/−} hypothyroid mice, and this induction was abolished in CAR{sup −/−} mice and in and CAR{sup −/−} PXR{sup −/−} double knockouts. CAR mRNA expression was increased by hypothyroidism, while PXR expression remained unchanged. Carbamazepine (CBZ) is a commonly used antiepileptic that is metabolized by CYP3A isoforms. After CBZ treatment of normal chow fed mice, serum CBZ levels were highest in CAR{sup −/−} mice and lowest in WT and PXR{sup −/−} mice. Hypothyroid WT or PXR{sup −/−} mice survived chronic CBZ treatment, but all hypothyroid CAR{sup −/−} and CAR{sup −/−} PXR{sup −/−} mice died, with CAR{sup −/−}PXR{sup −/−} mice surviving longer than CAR{sup −/−} mice (12.3 ± 3.3 days vs. 6.3 ± 2.1 days, p = 0.04). All these findings suggest that hypothyroid status affects xenobiotic metabolism, with opposing responses of CAR and PXR and their CYP targets that can cancel each other out, decreasing serious metabolic derangement in response to a xenobiotic challenge. -- Highlights: ► Hypothyroid status activates CAR in mice and induces Cyp2b10 expression. ► Hypothyroid status suppresses PXR activity in mice and represses Cyp3a11 expression. ► These responses balance each other out in normal mice. �

Hepatic and renal Bcrp transporter expression in mice treated with perfluorooctanoic acid

International Nuclear Information System (INIS)

Eldasher, Lobna M.; Wen, Xia; Little, Michael S.; Bircsak, Kristin M.; Yacovino, Lindsay L.; Aleksunes, Lauren M.

2013-01-01

Highlights: ► PFOA increased liver weight and Cyp4a14 mRNA and protein expression in mice. ► PFOA increased kidney Cyp4a14 mRNA in mice. ► PFOA increased Bcrp mRNA and protein in livers, but not kidneys, of mice. ► PFOA inhibited activation of human BCRP ATPase activity in vitro. ► PFOA inhibited human BCRP transport in inverted membrane vesicles. - Abstract: The breast cancer resistance protein (Bcrp) is an efflux transporter that participates in the biliary and renal excretion of drugs and environmental chemicals. Recent evidence suggests that pharmacological activation of the peroxisome proliferator activated receptor alpha (PPARα) can up-regulate the hepatic expression of Bcrp. The current study investigated the regulation of hepatic and renal Bcrp mRNA and protein in mice treated with the PPARα agonist perfluorooctanoic acid (PFOA) and the ability of PFOA to alter human BCRP function in vitro. Bcrp mRNA and protein expression were quantified in the livers and kidneys of male C57BL/6 mice treated with vehicle or PFOA (1 or 3 mg/kg/day oral gavage) for 7 days. PFOA treatment increased liver weights as well as the hepatic mRNA and protein expression of the PPARα target gene, cytochrome P450 4a14. Compared to vehicle-treated control mice, PFOA increased hepatic Bcrp mRNA and protein between 1.5- and 3-fold. Immunofluorescent staining confirmed enhanced canalicular Bcrp staining in liver sections from PFOA-treated mice. The kidney expression of cytochrome P450 4a14 mRNA, but not Bcrp, was increased in mice treated with PFOA. Micromolar concentrations of PFOA decreased human BCRP ATPase activity and inhibited BCRP-mediated transport in inverted membrane vesicles. Together, these studies demonstrate that PFOA induces hepatic Bcrp expression in mice and may inhibit human BCRP transporter function at concentrations that exceed levels observed in humans

The different effects of over-expressing murine NMDA receptor 2B subunit in the forebrain on conditioned taste aversion.

Science.gov (United States)

Li, Shijia; Gu, Yiran; Meng, Bo; Mei, Bing; Li, Fei

2010-09-10

The glutamate transmission system and the N-methyl-D-aspartate receptor (NMDA-R), in particular its 2B subunit (NR2B), have been reported to be possibly related to taste memory as a result of treatment with NMDA antagonists and agonists. In order to further study the role of the NR2B subunit in gustation memory, we applied four different taste aversive tasks to observe the behavior of a transgenic mice model in which the NR2B subunit was specifically over-expressed in the forebrain. We found that in both short- and long-term conditioned taste aversion (CTA) experiments, mice with forebrain expression of the NR2B transgene (Tg) showed significantly enhanced CTA 2 days after training. However, both the Tg and the wild-type (Wt) mice shared the same level of aversive memory on the 30th day after training. In both fast and slow extinction experiments, Tg mice maintained a higher CTA memory than that of control mice in most extinction trials. The third experiment, which involved testing the memory for familiar taste, demonstrated that NR2B augmentation had no benefit on the latent inhibition (LI) of CTA. In addition, the last experiment (two-taste LI) showed a suppression of enhanced CTA in Tg mice when the mice were exposed to both novel and familiar tastes. These data suggested that forebrain NR2B over-expression had different effects on gustatory learning and memory. The transgenic animals were only sensitive to novel but not familiar tastes, and up-regulation of NR2B resulted in enhanced CTA function for only a short period of time. 2010 Elsevier B.V. All rights reserved.

Erythropoietin over-expression protects against diet-induced obesity in mice through increased fat oxidation in muscles.

Science.gov (United States)

Hojman, Pernille; Brolin, Camilla; Gissel, Hanne; Brandt, Claus; Zerahn, Bo; Pedersen, Bente Klarlund; Gehl, Julie

2009-06-12

Erythropoietin can be over-expressed in skeletal muscles by gene electrotransfer, resulting in 100-fold increase in serum EPO and significant increases in haemoglobin levels. Earlier studies have suggested that EPO improves several metabolic parameters when administered to chronically ill kidney patients. Thus we applied the EPO over-expression model to investigate the metabolic effect of EPO in vivo.At 12 weeks, EPO expression resulted in a 23% weight reduction (Pincrease in muscle volume and a 25% increase in vascularisation of the EPO transfected muscle. Muscle force and stamina were not affected by EPO expression. PCR array analysis revealed that genes involved in lipid metabolism, thermogenesis and inflammation were increased in muscles in response to EPO expression, while genes involved in glucose metabolism were down-regulated. In addition, muscular fat oxidation was increased 1.8-fold in both the EPO transfected and contralateral muscles.In conclusion, we have shown that EPO when expressed in supra-physiological levels has substantial metabolic effects including protection against diet-induced obesity and normalisation of glucose sensitivity associated with a shift to increased fat metabolism in the muscles.

Loss of Function of P2X7 Receptor Scavenger Activity in Aging Mice: A Novel Model for Investigating the Early Pathogenesis of Age-Related Macular Degeneration.

Science.gov (United States)

Vessey, Kirstan A; Gu, Ben J; Jobling, Andrew I; Phipps, Joanna A; Greferath, Ursula; Tran, Mai X; Dixon, Michael A; Baird, Paul N; Guymer, Robyn H; Wiley, James S; Fletcher, Erica L

2017-08-01

Age-related macular degeneration (AMD) is a leading cause of irreversible, severe vision loss in Western countries. Recently, we identified a novel pathway involving P2X7 receptor scavenger function expressed on ocular immune cells as a risk factor for advanced AMD. In this study, we investigate the effect of loss of P2X7 receptor function on retinal structure and function during aging. P2X7-null and wild-type C57bl6J mice were investigated at 4, 12, and 18 months of age for macrophage phagocytosis activity, ocular histological changes, and retinal function. Phagocytosis activity of blood-borne macrophages decreased with age at 18 months in the wild-type mouse. Lack of P2X7 receptor function reduced phagocytosis at all ages compared to wild-type mice. At 12 months of age, P2X7-null mice had thickening of Bruchs membrane and retinal pigment epithelium dysfunction. By 18 months of age, P2X7-null mice displayed phenotypic characteristics consistent with early AMD, including Bruchs membrane thickening, retinal pigment epithelium cell loss, retinal functional deficits, and signs of subretinal inflammation. Our present study shows that loss of function of the P2X7 receptor in mice induces retinal changes representing characteristics of early AMD, providing a valuable model for investigating the role of scavenger receptor function and the immune system in the development of this age-related disease. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

The Development of Spasmolytic Polypeptide/TFF2-Expressing Metaplasia (SPEM During Gastric Repair Is Absent in the Aged StomachSummary

Directory of Open Access Journals (Sweden)

Amy C. Engevik

2016-09-01

Full Text Available Background & Aims: During aging, physiological changes in the stomach result in more tenuous gastric tissue that is less capable of repairing injury, leading to increased susceptibility to chronic ulceration. Spasmolytic polypeptide/trefoil factor 2–expressing metaplasia (SPEM is known to emerge after parietal cell loss and during Helicobacter pylori infection, however, its role in gastric ulcer repair is unknown. Therefore, we sought to investigate if SPEM plays a role in epithelial regeneration. Methods: Acetic acid ulcers were induced in young (2–3 mo and aged (18–24 mo C57BL/6 mice to determine the quality of ulcer repair with advancing age. Yellow chameleon 3.0 mice were used to generate yellow fluorescent protein–expressing organoids for transplantation. Yellow fluorescent protein–positive gastric organoids were transplanted into the submucosa and lumen of the stomach immediately after ulcer induction. Gastric tissue was collected and analyzed to determine the engraftment of organoid-derived cells within the regenerating epithelium. Results: Wound healing in young mice coincided with the emergence of SPEM within the ulcerated region, a response that was absent in the aged stomach. Although aged mice showed less metaplasia surrounding the ulcerated tissue, organoid-transplanted aged mice showed regenerated gastric glands containing organoid-derived cells. Organoid transplantation in the aged mice led to the emergence of SPEM and gastric regeneration. Conclusions: These data show the development of SPEM during gastric repair in response to injury that is absent in the aged stomach. In addition, gastric organoids in an injury/transplantation mouse model promoted gastric regeneration. Keywords: Epithelial Regeneration, Gastric Cancer, Human Gastric Organoids, CD44v

Ectopic expression of the agouti gene in transgenic mice causes obesity, features of type II diabetes, and yellow fur

Energy Technology Data Exchange (ETDEWEB)

Klebig, M.L.; Woychik, R.P. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Wilkinson, J.E. [Univ. of Tennessee, Knoxville, TN (United States); Geisler, J.G. [Oak Ridge National Laboratory, Oak Ridge, TN (United States)]|[Univ. of Tennessee, Knoxville, TN (United States)

1995-05-23

Mice that carry the lethal yellow (A{sup y}) or viable yellow (A{sup vy}) mutation, two dominant mutations of the agouti (a) gene in mouse chromosome 2, exhibit a phenotype that includes yellow fur, marked obesity, a form of type II diabetes associated with insulin resistance, and an increased susceptibility to tumor development. Molecular analyses of these and several other dominant {open_quotes}obese yellow{close_quotes} a-locus mutations suggested that ectopic expression of the normal agouti protein gives rise to this complex pleiotropic phenotype. We have now tested this hypothesis directly by generating transgenic mice that ectopically express an agouti cDNA clone encoding the normal agouti protein in all tissues examined. Transgenic mice of both sexes have yellow fur, become obese, and develop hyperinsulinemia. In addition, male transgenic mice develop hyperglycemia by 12-20 weeks of age. These results demonstrate conclusively that the ectopic agouti expression is responsible for most, if not all, of the phenotypic traits of the dominant, obese yellow mutants. 42 refs., 5 figs.

Growth Hormone-Releaser Diet Attenuates Cognitive Dysfunction in Klotho Mutant Mice via Insulin-Like Growth Factor-1 Receptor Activation in a Genetic Aging Model

Directory of Open Access Journals (Sweden)

Seok Joo Park

2014-09-01

Full Text Available BackgroundIt has been recognized that a defect in klotho gene expression accelerates the degeneration of multiple age-sensitive traits. Accumulating evidence indicates that aging is associated with declines in cognitive function and the activity of growth hormone (GH/insulin-like growth factor-1 (IGF-1.MethodsIn this study, we examined whether a GH-releaser diet could be effective in protecting against cognitive impairment in klotho mutant mice.ResultsThe GH-releaser diet significantly induced the expression of IGF-1 and IGF-1 receptors in the hippocampus of klotho mutant mice. Klotho mutant mice showed significant memory impairments as compared with wild-type mice. In addition, the klotho mutation significantly decreased the expression of cell survival/antiapoptotic factors, including phospho-Akt (p-Akt/phospho-glycogen synthase kinase3β (p-GSK3β, phospho-extracellular signal-related kinase (p-ERK, and Bcl-2, but significantly increased those of cell death/proapoptotic factors, such as phospho-c-jun N-terminal kinase (p-JNK, Bax, and cleaved caspase-3 in the hippocampus. Treatment with GH-releaser diet significantly attenuated both decreases in the expression of cell survival/antiapoptotic factors and increases in the expression of cell death/proapoptotic factors in the hippocampus of klotho mutant mice. In addition, klotho mutation-induced oxidative stress was significantly attenuated by the GH-releaser diet. Consequently, a GH-releaser diet significantly improved memory function in the klotho mutant mice. GH-releaser diet-mediated actions were significantly reversed by JB-1, an IGF-1 receptor antagonist.ConclusionThe results suggest that a GH-releaser diet attenuates oxidative stress, proapoptotic changes and consequent dysfunction in klotho mutant mice by promoting IGF-1 expression and IGF-1 receptor activation.

Cyclophilin D Promotes Brain Mitochondrial F1FO ATP Synthase Dysfunction in Aging Mice.

Science.gov (United States)

Gauba, Esha; Guo, Lan; Du, Heng

2017-01-01

Brain aging is the known strongest risk factor for Alzheimer's disease (AD). In recent years, mitochondrial deficits have been proposed to be a common mechanism linking brain aging to AD. Therefore, to elucidate the causative mechanisms of mitochondrial dysfunction in aging brains is of paramount importance for our understanding of the pathogenesis of AD, in particular its sporadic form. Cyclophilin D (CypD) is a specific mitochondrial protein. Recent studies have shown that F1FO ATP synthase oligomycin sensitivity conferring protein (OSCP) is a binding partner of CypD. The interaction of CypD with OSCP modulates F1FO ATP synthase function and mediates mitochondrial permeability transition pore (mPTP) opening. Here, we have found that increased CypD expression, enhanced CypD/OSCP interaction, and selective loss of OSCP are prominent brain mitochondrial changes in aging mice. Along with these changes, brain mitochondria from the aging mice demonstrated decreased F1FO ATP synthase activity and defective F1FO complex coupling. In contrast, CypD deficient mice exhibited substantially mitigated brain mitochondrial F1FO ATP synthase dysfunction with relatively preserved mitochondrial function during aging. Interestingly, the aging-related OSCP loss was also dramatically attenuated by CypD depletion. Therefore, the simplest interpretation of this study is that CypD promotes F1FO ATP synthase dysfunction and the resultant mitochondrial deficits in aging brains. In addition, in view of CypD and F1FO ATP synthase alterations seen in AD brains, the results further suggest that CypD-mediated F1FO ATP synthase deregulation is a shared mechanism linking mitochondrial deficits in brain aging and AD.

c-Fos expression during temporal order judgment in mice.

Directory of Open Access Journals (Sweden)

Makoto Wada

Full Text Available The neuronal mechanisms for ordering sensory signals in time still need to be clarified despite a long history of research. To address this issue, we recently developed a behavioral task of temporal order judgment in mice. In the present study, we examined the expression of c-Fos, a marker of neural activation, in mice just after they carried out the temporal order judgment task. The expression of c-Fos was examined in C57BL/6N mice (male, n = 5 that were trained to judge the order of two air-puff stimuli delivered bilaterally to the right and left whiskers with stimulation intervals of 50-750 ms. The mice were rewarded with a food pellet when they responded by orienting their head toward the first stimulus (n = 2 or toward the second stimulus (n = 3 after a visual "go" signal. c-Fos-stained cell densities of these mice (test group were compared with those of two control groups in coronal brain sections prepared at bregma -2, -1, 0, +1, and +2 mm by applying statistical parametric mapping to the c-Fos immuno-stained sections. The expression of c-Fos was significantly higher in the test group than in the other groups in the bilateral barrel fields of the primary somatosensory cortex, the left secondary somatosensory cortex, the dorsal part of the right secondary auditory cortex. Laminar analyses in the primary somatosensory cortex revealed that c-Fos expression in the test group was most evident in layers II and III, where callosal fibers project. The results suggest that temporal order judgment involves processing bilateral somatosensory signals through the supragranular layers of the primary sensory cortex and in the multimodal sensory areas, including marginal zone between the primary somatosensory cortex and the secondary sensory cortex.

Enhanced IL-1beta production in response to the activation of hippocampal glial cells impairs neurogenesis in aged mice.

Science.gov (United States)

Kuzumaki, Naoko; Ikegami, Daigo; Imai, Satoshi; Narita, Michiko; Tamura, Rie; Yajima, Marie; Suzuki, Atsuo; Miyashita, Kazuhiko; Niikura, Keiichi; Takeshima, Hideyuki; Ando, Takayuki; Ushijima, Toshikazu; Suzuki, Tsutomu; Narita, Minoru

2010-09-01

A variety of mechanisms that contribute to the accumulation of age-related damage and the resulting brain dysfunction have been identified. Recently, decreased neurogenesis in the hippocampus has been recognized as one of the mechanisms of age-related brain dysfunction. However, the molecular mechanism of decreased neurogenesis with aging is still unclear. In the present study, we investigated whether aging decreases neurogenesis accompanied by the activation of microglia and astrocytes, which increases the expression of IL-1beta in the hippocampus, and whether in vitro treatment with IL-1beta in neural stem cells directly impairs neurogenesis. Ionized calcium-binding adaptor molecule 1 (Iba1)-positive microglia and glial fibrillary acidic protein (GFAP)-positive astrocytes were increased in the dentate gyrus of the hippocampus of 28-month-old mice. Furthermore, the mRNA level of IL-1beta was significantly increased without related histone modifications. Moreover, a significant increase in lysine 9 on histone H3 (H3K9) trimethylation at the promoter of NeuroD (a neural progenitor cell marker) was observed in the hippocampus of aged mice. In vitro treatment with IL-1beta in neural stem cells prepared from whole brain of E14.5 mice significantly increased H3K9 trimethylation at the NeuroD promoter. These findings suggest that aging may decrease hippocampal neurogenesis via epigenetic modifications accompanied by the activation of microglia and astrocytes with the increased expression of IL-1beta in the hippocampus.

Resilience in Aging Mice.

Science.gov (United States)

Kirkland, James L; Stout, Michael B; Sierra, Felipe

2016-11-01

Recently discovered interventions that target fundamental aging mechanisms have been shown to increase life span in mice and other species, and in some cases, these same manipulations have been shown to enhance health span and alleviate multiple age-related diseases and conditions. Aging is generally associated with decreases in resilience, the capacity to respond to or recover from clinically relevant stresses such as surgery, infections, or vascular events. We hypothesize that the age-related increase in susceptibility to those diseases and conditions is driven by or associated with the decrease in resilience. Thus, a test for resilience at middle age or even earlier could represent a surrogate approach to test the hypothesis that an intervention delays the process of aging itself. For this, animal models to test resilience accurately and predictably are needed. In addition, interventions that increase resilience might lead to treatments aimed at enhancing recovery following acute illnesses, or preventing poor outcomes from medical interventions in older, prefrail subjects. At a meeting of basic researchers and clinicians engaged in research on mechanisms of aging and care of the elderly, the merits and drawbacks of investigating effects of interventions on resilience in mice were considered. Available and potential stressors for assessing physiological resilience as well as the notion of developing a limited battery of such stressors and how to rank them were discussed. Relevant ranking parameters included value in assessing general health (as opposed to focusing on a single physiological system), ease of use, cost, reproducibility, clinical relevance, and feasibility of being repeated in the same animal longitudinally. During the discussions it became clear that, while this is an important area, very little is known or established. Much more research is needed in the near future to develop appropriate tests of resilience in animal models within an aging context

Increased 4E-BP1 Expression Protects against Diet-Induced Obesity and Insulin Resistance in Male Mice

Directory of Open Access Journals (Sweden)

Shih-Yin Tsai

2016-08-01

Full Text Available Obesity is a major risk factor driving the global type II diabetes pandemic. However, the molecular factors linking obesity to disease remain to be elucidated. Gender differences are apparent in humans and are also observed in murine models. Here, we link these differences to expression of eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1, which, upon HFD feeding, becomes significantly reduced in the skeletal muscle and adipose tissue of male but not female mice. Strikingly, restoring 4E-BP1 expression in male mice protects them against HFD-induced obesity and insulin resistance. Male 4E-BP1 transgenic mice also exhibit reduced white adipose tissue accumulation accompanied by decreased circulating levels of leptin and triglycerides. Importantly, transgenic 4E-BP1 male mice are also protected from aging-induced obesity and metabolic decline on a normal diet. These results demonstrate that 4E-BP1 is a gender-specific suppressor of obesity that regulates insulin sensitivity and energy metabolism.

Differential tissue expression of enhanced green fluorescent protein in 'green mice'.

Science.gov (United States)

Ma, De-Fu; Tezuka, Hideo; Kondo, Tetsuo; Sudo, Katsuko; Niu, Dong-Feng; Nakazawa, Tadao; Kawasaki, Tomonori; Yamane, Tetsu; Nakamura, Nobuki; Katoh, Ryohei

2010-06-01

In order to clarify tissue expression of enhanced green fluorescent protein (EGFP) in 'green mice' from a transgenic line having an EGFP cDNA under the control of a chicken beta-actin promoter and cytomegalovirus enhancer, we studied the expression of EGFP in various organs and tissues from these 'green mice' by immunohistochemistry with anti- EGFP antibody in conjunction with direct observation for EGFP fluorescence using confocal laser scanning microscopy. On immunohistochemical examination and on direct observation by confocal laser scanning microscopy, the level of EGFP expression varied among organs and tissues. EGFP expression was diffusely and strongly observed in the skin, pituitary, thyroid gland, parathyroid gland, heart, gall bladder, pancreas, adrenals and urinary bladder. There was only sporadic and weak expression of EGFP in the epithelium of the trachea, bronchus of the lung, stratified squamous epithelium and gastric glands of the stomach, hepatic bile ducts of the liver, glomeruli and renal tubules of the kidney and endo-metrial glands of the uterus. Furthermore, EGFP was only demonstrated within the goblet and paneth cells in the colon and small intestine, the tall columnar cells in the ductus epididymis, and the leydig cells in the testis. In conclusion, our results show that EGFP is differentially expressed in organs and tissues of 'green mice', which indicates that 'green mice' may prove useful for research involving transplantation and tissue clonality.

Differential Gene Expression and Aging

Directory of Open Access Journals (Sweden)

Laurent Seroude

2002-01-01

Full Text Available It has been established that an intricate program of gene expression controls progression through the different stages in development. The equally complex biological phenomenon known as aging is genetically determined and environmentally modulated. This review focuses on the genetic component of aging, with a special emphasis on differential gene expression. At least two genetic pathways regulating organism longevity act by modifying gene expression. Many genes are also subjected to age-dependent transcriptional regulation. Some age-related gene expression changes are prevented by caloric restriction, the most robust intervention that slows down the aging process. Manipulating the expression of some age-regulated genes can extend an organism's life span. Remarkably, the activity of many transcription regulatory elements is linked to physiological age as opposed to chronological age, indicating that orderly and tightly controlled regulatory pathways are active during aging.

Chronic Endurance Exercise Impairs Cardiac Structure and Function in Middle-Aged Mice with Impaired Nrf2 Signaling

Directory of Open Access Journals (Sweden)

Gobinath Shanmugam

2017-05-01

Full Text Available Nuclear factor erythroid 2 related factor 2 (Nrf2 signaling maintains the redox homeostasis and its activation is shown to suppress cardiac maladaptation. Earlier we reported that acute endurance exercise (2 days evoked antioxidant cytoprotection in young WT animals but not in aged WT animals. However, the effect of repeated endurance exercise during biologic aging (WT characterized by an inherent deterioration in Nrf2 signaling and pathological aging (pronounced oxidative susceptibility—Nrf2 absence in the myocardium remains elusive. Thus, the purpose of our study was to determine the effect of chronic endurance exercise-induced cardiac adaptation in aged mice with and without Nrf2. Age-matched WT and Nrf2-null mice (Nrf2−/− (>22 months were subjected to 6 weeks chronic endurance exercise (25 meter/min, 12% grade. The myocardial redox status was assessed by expression of antioxidant defense genes and proteins along with immunochemical detection of DMPO-radical adduct, GSH-NEM, and total ubiquitination. Cardiac functions were assessed by echocardiography and electrocardiogram. At sedentary state, loss of Nrf2 resulted in significant downregulation of antioxidant gene expression (Nqo1, Ho1, Gclm, Cat, and Gst-α with decreased GSH-NEM immuno-fluorescence signals. While Nrf2−/− mice subjected to CEE showed an either similar or more pronounced reduction in the transcript levels of Gclc, Nqo1, Gsr, and Gst-α in relation to WT littermates. In addition, the hearts of Nrf2−/− on CEE showed a substantial reduction in specific antioxidant proteins, G6PD and CAT along with decreased GSH, a pronounced increase in DMPO-adduct and the total ubiquitination levels. Further, CEE resulted in a significant upregulation of hypertrophy genes (Anf, Bnf, and β-Mhc (p < 0.05 in the Nrf2−/− hearts in relation to WT mice. Moreover, the aged Nrf2−/− mice exhibited a higher degree of cardiac remodeling in association with a significant decrease in

Central diabetes insipidus associated with impaired renal aquaporin-1 expression in mice lacking liver X receptor β.

Science.gov (United States)

Gabbi, Chiara; Kong, Xiaomu; Suzuki, Hitoshi; Kim, Hyun-Jin; Gao, Min; Jia, Xiao; Ohnishi, Hideo; Ueta, Yoichi; Warner, Margaret; Guan, Youfei; Gustafsson, Jan-Åke

2012-02-21

The present study demonstrates a key role for the oxysterol receptor liver X receptor β (LXRβ) in the etiology of diabetes insipidus (DI). Given free access to water, LXRβ(-/-) but not LXRα(-/-) mice exhibited polyuria (abnormal daily excretion of highly diluted urine) and polydipsia (increased water intake), both features of diabetes insipidus. LXRβ(-/-) mice responded to 24-h dehydration with a decreased urine volume and increased urine osmolality. To determine whether the DI was of central or nephrogenic origin, we examined the responsiveness of the kidney to arginine vasopressin (AVP). An i.p. injection of AVP to LXRβ(-/-) mice revealed a partial kidney response: There was no effect on urine volume, but there was a significant increase of urine osmolality, suggesting that DI may be caused by a defect in central production of AVP. In the brain of WT mice LXRβ was expressed in the nuclei of magnocellular neurons in the supraoptic and paraventricular nuclei of the hypothalamus. In LXRβ(-/-) mice the expression of AVP was markedly decreased in the magnocellular neurons as well as in urine collected over a 24-h period. The persistent high urine volume after AVP administration was traced to a reduction in aquaporin-1 expression in the kidney of LXRβ(-/-) mice. The LXR agonist (GW3965) in WT mice elicited an increase in urine osmolality, suggesting that LXRβ is a key receptor in controlling water balance with targets in both the brain and kidney, and it could be a therapeutic target in disorders of water balance.

Transgenic neuronal expression of proopiomelanocortin attenuates hyperphagic response to fasting and reverses metabolic impairments in leptin-deficient obese mice.

Science.gov (United States)

Mizuno, Tooru M; Kelley, Kevin A; Pasinetti, Giulio M; Roberts, James L; Mobbs, Charles V

2003-11-01

Hypothalamic proopiomelanocortin (POMC) gene expression is reduced in many forms of obesity and diabetes, particularly in those attributable to deficiencies in leptin or its receptor. To assess the functional significance of POMC in mediating metabolic phenotypes associated with leptin deficiency, leptin-deficient mice bearing a transgene expressing the POMC gene under control of the neuron-specific enolase promoter were produced. The POMC transgene attenuated fasting-induced hyperphagia in wild-type mice. Furthermore, the POMC transgene partially reversed obesity, hyperphagia, and hypothermia and effectively normalized hyperglycemia, glucosuria, glucose intolerance, and insulin resistance in leptin-deficient mice. Effects of the POMC transgene on glucose homeostasis were independent of the partial correction of hyperphagia and obesity. Furthermore, the POMC transgene normalized the profile of hepatic and adipose gene expression associated with gluconeogenesis, glucose output, and insulin sensitivity. These results indicate that central POMC is a key modulator of glucose homeostasis and that agonists of POMC products may provide effective therapy in treating impairments in glucose homeostasis when hypothalamic POMC expression is reduced, as occurs with leptin deficiency, hypothalamic damage, and aging.

Effect of age on the expression of Pex (Phex) in the mouse.

Science.gov (United States)

Meyer, R A; Young, C G; Meyer, M H; Garges, P L; Price, D K

2000-04-01

Pex is a newly discovered gene (also called Phex) whose mutation is the cause of X-linked hypophosphatemia. Other members of this gene family encode endopeptidases that activate or inactivate endocrine and paracrine factors. Though embryonic bone expresses mRNA for the Pex gene at relatively high levels, we have found Pex expression to be widespread in adult organs and to be poorly expressed in adult bone. This led to the hypothesis that Pex mRNA expression changes with age. To test this, genetically normal mice of the B6C3H hybrid strain were studied at 0 (newborn), 2, 3, 10, and 72 weeks of age. Organs known to express Pex were collected, and RNA was extracted from them. Following reverse transcription, cDNA was amplified by the polymerase chain reaction with primers for Pex and G3PDH, a housekeeping gene. The amplimers were separated by electrophoresis, blotted onto nylon membranes, and hybridized with radioactively labeled internal oligonucleotide probes. The radioactivity was quantified, and the data were analyzed as the Pex/G3PDH ratio. The brain samples had high levels of Pex mRNA expression that rose slightly with age. Calvaria, kidney, and lung samples had the highest Pex mRNA expression at birth. In these organs Pex mRNA expression fell with age to undetectable or barely detectable levels. Thymus, heart, and skeletal muscle samples had low Pex mRNA expression at birth that did not change with age. Some organs showed a decline in G3PDH levels with age, but Pex expression decreased more, leading to a reduced Pex/G3PDH ratio. The widespread expression of mRNA for Pex suggests a role beyond that of phosphate homeostasis. The high level of expression in newborn animals suggests a role in growth and development. This seems to occur in addition to its role for the endocrine regulation of phosphate homeostasis by as yet unknown humoral agents that must occur throughout life. In summary, Pex mRNA expression is high in brain and bone at birth. Expression remains

Immunoglobulin gene expression and regulation of rearrangement in kappa transgenic mice

International Nuclear Information System (INIS)

Ritchie, K.A.

1986-01-01

Transgenic mice were produced by microinjection of the functionally rearranged immunoglobulin kappa gene from the myeloma MOPC-21 into the male pronucleus of fertilized mouse eggs, and implantation of the microinjected embryos into foster mothers. Mice that integrated the injected gene were detected by hybridizing tail DNA dots with radioactively labelled pBR322 plasmid DNA, which detects pBR322 sequences left as a tag on the microinjected DNA. Mice that integrated the injected gene (six males) were mated and the DNA, RNA and serum kappa chains of their offspring were analyzed. A rabbit anti-mouse kappa chain antiserum was also produced for use in detection of mouse kappa chains on protein blots. Hybridomas were produced from the spleen cells of these kappa transgenic mice to immortalize representative B cells and to investigate expression of the transgenic kappa gene, its effect on allelic exclusion, and its effect on the control of light chain gene rearrangement and expression. The results show that the microinjected DNA is integrated as concatamers in unique single or, rarely, two separate sites in the genome. The concatamers are composed of several copies (16 to 64) of injected DNA arranged in a head to tail fashion. The transgene is expressed into protein normally and in a tissue specific fashion. For the first time in these transgenic mice, all tissues contain a functionally rearranged and potentially expressible immunoglobulin gene. The transgene is expressed only in B cells and not in hepatocytes, for example. This indicates that rearrangement of immunoglobulin genes is necessary but not sufficient for the tissue specific expression of these genes by B cells

Clock Genes Influence Gene Expression in Growth Plate and Endochondral Ossification in Mice*

Science.gov (United States)

Takarada, Takeshi; Kodama, Ayumi; Hotta, Shogo; Mieda, Michihiro; Shimba, Shigeki; Hinoi, Eiichi; Yoneda, Yukio

2012-01-01

We have previously shown transient promotion by parathyroid hormone of Period-1 (Per1) expression in cultured chondrocytes. Here we show the modulation by clock genes of chondrogenic differentiation through gene transactivation of the master regulator of chondrogenesis Indian hedgehog (IHH) in chondrocytes of the growth plate. Several clock genes were expressed with oscillatory rhythmicity in cultured chondrocytes and rib growth plate in mice, whereas chondrogenesis was markedly inhibited in stable transfectants of Per1 in chondrocytic ATDC5 cells and in rib growth plate chondrocytes from mice deficient of brain and muscle aryl hydrocarbon receptor nuclear translocator-like (BMAL1). Ihh promoter activity was regulated by different clock gene products, with clear circadian rhythmicity in expression profiles of Ihh in the growth plate. In BMAL1-null mice, a predominant decrease was seen in Ihh expression in the growth plate with a smaller body size than in wild-type mice. BMAL1 deficit led to disruption of the rhythmic expression profiles of both Per1 and Ihh in the growth plate. A clear rhythmicity was seen with Ihh expression in ATDC5 cells exposed to dexamethasone. In young mice defective of BMAL1 exclusively in chondrocytes, similar abnormalities were found in bone growth and Ihh expression. These results suggest that endochondral ossification is under the regulation of particular clock gene products expressed in chondrocytes during postnatal skeletogenesis through a mechanism relevant to the rhythmic Ihh expression. PMID:22936800

Motor performance is impaired following vestibular stimulation in ageing mice.

Directory of Open Access Journals (Sweden)

Victoria W.K. Tung

2016-02-01

Full Text Available Balance and maintaining postural equilibrium are important during stationary and dynamic movements to prevent falls, particularly in older adults. While our sense of balance is influenced by vestibular, proprioceptive, and visual information, this study focuses primarily on the vestibular component and its age-related effects on balance. C57Bl/6J mice of ages 1, 5-6, 8-9 and 27-28 months were tested using a combination of standard (such as grip strength and rotarod and newly-developed behavioural tests (including balance beam and walking trajectory tests with a vestibular stimulus. In the current study, we confirm a decline in fore-limb grip strength and gross motor coordination as age increases. We also show that a vestibular stimulus of low frequency (2-3 Hz and duration can lead to age-dependent changes in balance beam performance, which was evident by increases in latency to begin walking on the beam as well as the number of times hind-feet slip from the beam. Furthermore, aged mice (27-28 months that received continuous access to a running wheel for 4 weeks did not improve when retested. Mice of ages 1, 10, 13, and 27-28 months were also tested for changes in walking trajectory as a result of the vestibular stimulus. While no linear relationship was observed between the changes in trajectory and age, 1-month-old mice were considerably less affected than mice of ages 10, 13, and 27-28 months. Conclusion: This study confirms there are age-related declines in grip strength and gross motor coordination. We also demonstrate age-dependent changes to finer motor abilities as a result of a low frequency and duration vestibular stimulus. These changes showed that while the ability to perform the balance beam task remained intact across all ages tested, behavioural changes in task performance were observed.

Motor Performance is Impaired Following Vestibular Stimulation in Ageing Mice.

Science.gov (United States)

Tung, Victoria W K; Burton, Thomas J; Quail, Stephanie L; Mathews, Miranda A; Camp, Aaron J

2016-01-01

Balance and maintaining postural equilibrium are important during stationary and dynamic movements to prevent falls, particularly in older adults. While our sense of balance is influenced by vestibular, proprioceptive, and visual information, this study focuses primarily on the vestibular component and its age-related effects on balance. C57Bl/6J mice of ages 1, 5-6, 8-9 and 27-28 months were tested using a combination of standard (such as grip strength and rotarod) and newly-developed behavioral tests (including balance beam and walking trajectory tests with a vestibular stimulus). In the current study, we confirm a decline in fore-limb grip strength and gross motor coordination as age increases. We also show that a vestibular stimulus of low frequency (2-3 Hz) and duration can lead to age-dependent changes in balance beam performance, which was evident by increases in latency to begin walking on the beam as well as the number of times hind-feet slip (FS) from the beam. Furthermore, aged mice (27-28 months) that received continuous access to a running wheel for 4 weeks did not improve when retested. Mice of ages 1, 10, 13 and 27-28 months were also tested for changes in walking trajectory as a result of the vestibular stimulus. While no linear relationship was observed between the changes in trajectory and age, 1-month-old mice were considerably less affected than mice of ages 10, 13 and 27-28 months. this study confirms there are age-related declines in grip strength and gross motor coordination. We also demonstrate age-dependent changes to finer motor abilities as a result of a low frequency and duration vestibular stimulus. These changes showed that while the ability to perform the balance beam task remained intact across all ages tested, behavioral changes in task performance were observed.

Chronic inflammation induces telomere dysfunction and accelerates ageing in mice

NARCIS (Netherlands)

Jurk, Diana; Wilson, Caroline; Passos, Joao F.; Oakley, Fiona; Correia-Melo, Clara; Greaves, Laura; Saretzki, Gabriele; Fox, Chris; Lawless, Conor; Anderson, Rhys; Hewitt, Graeme; Pender, Sylvia L. F.; Fullard, Nicola; Nelson, Glyn; Mann, Jelena; van de Sluis, Bart; Mann, Derek A.; von Zglinicki, Thomas

Chronic inflammation is associated with normal and pathological ageing. Here we show that chronic, progressive low-grade inflammation induced by knockout of the nfkb1 subunit of the transcription factor NF-kappa B induces premature ageing in mice. We also show that these mice have reduced

A comparative study of age-related hearing loss in wild type and insulin-like growth factor I deficient mice

Directory of Open Access Journals (Sweden)

Raquel Riquelme

2010-06-01

Full Text Available Insulin-like growth factor-I (IGF-I belongs to the family of insulin-related peptides that fulfils a key role during the late development of the nervous system. Human IGF1 mutations cause profound deafness, poor growth and mental retardation. Accordingly, Igf1−/− null mice are dwarfs that have low survival rates, cochlear alterations and severe sensorineural deafness. Presbycusis (age-related hearing loss is a common disorder associated with aging that causes social and cognitive problems. Aging is also associated with a decrease in circulating IGF-I levels and this reduction has been related to cognitive and brain alterations, although there is no information as yet regarding the relationship between presbycusis and IGF-I biodisponibility. Here we present a longitudinal study of wild type Igf1+/+ and null Igf1−/− mice from 2 to 12 months of age comparing the temporal progression of several parameters: hearing, brain morphology, cochlear cytoarchitecture, insulin-related factors and IGF gene expression and IGF-I serum levels. Complementary invasive and non-invasive techniques were used, including auditory brainstem-evoked response (ABR recordings and in vivo MRI brain imaging. Igf1−/− null mice presented profound deafness at all the ages studied, without any obvious worsening of hearing parameters with aging. Igf1+/+ wild type mice suffered significant age-related hearing loss, their auditory thresholds and peak I latencies augmenting as they aged, in parallel with a decrease in the circulating levels of IGF-I. Accordingly, there was an age-related spiral ganglion degeneration in wild type mice that was not evident in the Igf1 null mice. However, the Igf1−/− null mice in turn developed a prematurely aged stria vascularis reminiscent of the diabetic strial phenotype. Our data indicate that IGF-I is required for the correct development and maintenance of hearing, supporting the idea that IGF-I-based therapies could contribute to

Myocardial KRAS(G12D) expression does not cause cardiomyopathy in mice.

Science.gov (United States)

Dalin, Martin G; Zou, Zhiyuan; Scharin-Täng, Margareta; Safari, Roghaiyeh; Karlsson, Christin; Bergo, Martin O

2014-02-01

Germ-line mutations in genes encoding components of the RAS/mitogen-activated protein kinase (MAPK) pathway cause developmental disorders called RASopathies. Hypertrophic cardiomyopathy (HCM) is the most common myocardial pathology and a leading cause of death in RASopathy patients. KRAS mutations are found in Noonan and cardio-facio-cutaneous syndromes. KRAS mutations, unlike mutations of RAF1 and HRAS, are rarely associated with HCM. This has been attributed to the fact that germ-line KRAS mutations cause only a moderate up-regulation of the MAPK pathway. Highly bioactive KRAS mutations have been hypothesized to cause severe cardiomyopathy incompatible with life. The aim of this study was to define the impact of KRAS(G12D) expression in the heart. To generate mice with endogenous cardiomyocyte-specific KRAS(G12D) expression (cKRAS(G12D) mice), we bred mice with a Cre-inducible allele expressing KRAS(G12D) from its endogenous promoter (Kras2(LSL)) to mice expressing Cre under control of the cardiomyocyte-specific α-myosin heavy chain promoter (αMHC-Cre). cKRAS(G12D) mice showed high levels of myocardial ERK and AKT signalling. However, surprisingly, cKRAS(G12D) mice were born in Mendelian ratios, appeared healthy, and had normal function, size, and histology of the heart. Mice with cardiomyocyte-specific KRAS(G12D) expression do not develop heart pathology. These results challenge the view that the level of MAPK activation correlates with the severity of HCM in RASopathies and suggests that MAPK-independent strategies may be of interest in the development of new treatments for these syndromes.

Transgenic Mice Over-Expressing RBP4 Have RBP4-Dependent and Light-Independent Retinal Degeneration.

Science.gov (United States)

Du, Mei; Phelps, Eric; Balangue, Michael J; Dockins, Aaron; Moiseyev, Gennadiy; Shin, Younghwa; Kane, Shelley; Otalora, Laura; Ma, Jian-Xing; Farjo, Rafal; Farjo, Krysten M

2017-08-01

Transgenic mice overexpressing serum retinol-binding protein (RBP4-Tg) develop progressive retinal degeneration, characterized by microglia activation, yet the precise mechanisms underlying retinal degeneration are unclear. Previous studies showed RBP4-Tg mice have normal ocular retinoid levels, suggesting that degeneration is independent of the retinoid visual cycle or light exposure. The present study addresses whether retinal degeneration is light-dependent and RBP4-dependent by testing the effects of dark-rearing and pharmacological lowering of serum RBP4 levels, respectively. RBP4-Tg mice reared on normal mouse chow in normal cyclic light conditions were directly compared to RBP4-Tg mice exposed to chow supplemented with the RBP4-lowering compound A1120 or dark-rearing conditions. Quantitative retinal histological analysis was conducted to assess retinal degeneration, and electroretinography (ERG) and optokinetic tracking (OKT) tests were performed to assess retinal and visual function. Ocular retinoids and bis-retinoid A2E were quantified. Dark-rearing RBP4-Tg mice effectively reduced ocular bis-retinoid A2E levels, but had no significant effect on retinal degeneration or dysfunction in RBP4-Tg mice, demonstrating that retinal degeneration is light-independent. A1120 treatment lowered serum RBP4 levels similar to wild-type mice, and prevented structural retinal degeneration. However, A1120 treatment did not prevent retinal dysfunction in RBP4-Tg mice. Moreover, RBP4-Tg mice on A1120 diet had significant worsening of OKT response and loss of cone photoreceptors compared to RBP4-Tg mice on normal chow. This may be related to the very significant reduction in retinyl ester levels in the retina of mice on A1120-supplemented diet. Retinal degeneration in RBP4-Tg mice is RBP4-dependent and light-independent.

Free-hand ultrasound guidance permits safe and efficient minimally invasive intrathymic injections in both young and aged mice.

Science.gov (United States)

Tuckett, Andrea Z; Zakrzewski, Johannes L; Li, Duan; van den Brink, Marcel R M; Thornton, Raymond H

2015-04-01

The goal of this study was to evaluate whether use of an aseptic free-hand approach to ultrasound-guided injection facilitates injection into the thymic gland in mice. We used this interventional radiology technique in young, aged and immunodeficient mice and found that the thymus was visible in all cases. The mean injection period was 8 seconds in young mice and 19 seconds in aged or immunodeficient mice. Injection accuracy was confirmed by intrathymic location of an injected dye or by in vivo bioluminescence imaging of injected luciferase-expressing cells. Accurate intrathymic injection was confirmed in 97% of cases. No major complications were observed. We conclude that an aseptic freehand technique for ultrasound-guided intrathymic injection is safe and accurate and reduces the time required for intrathymic injections. This method facilitates large-scale experiments and injection of individual thymic lobes and is clinically relevant. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Mitral and tufted cells are potential cellular targets of nitration in the olfactory bulb of aged mice.

Directory of Open Access Journals (Sweden)

Myung Jae Yang

Full Text Available Olfactory sensory function declines with age; though, the underlying molecular changes that occur in the olfactory bulb (OB are relatively unknown. An important cellular signaling molecule involved in the processing, modulation, and formation of olfactory memories is nitric oxide (NO. However, excess NO can result in the production of peroxynitrite to cause oxidative and nitrosative stress. In this study, we assessed whether changes in the expression of 3-nitrotyrosine (3-NT, a neurochemical marker of peroxynitrite and thus oxidative damage, exists in the OB of young, adult, middle-aged, and aged mice. Our results demonstrate that OB 3-NT levels increase with age in normal C57BL/6 mice. Moreover, in aged mice, 3-NT immunoreactivity was found in some blood vessels and microglia throughout the OB. Notably, large and strongly immunoreactive puncta were found in mitral and tufted cells, and these were identified as lipofuscin granules. Additionally, we found many small-labeled puncta within the glomeruli of the glomerular layer and in the external plexiform layer, and these were localized to mitochondria and discrete segments of mitral and tufted dendritic plasma membranes. These results suggest that mitral and tufted cells are potential cellular targets of nitration, along with microglia and blood vessels, in the OB during aging.

Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

Science.gov (United States)

Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

2001-01-01

Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

Marginal level dystrophin expression improves clinical outcome in a strain of dystrophin/utrophin double knockout mice.

Directory of Open Access Journals (Sweden)

Dejia Li

2010-12-01

Full Text Available Inactivation of all utrophin isoforms in dystrophin-deficient mdx mice results in a strain of utrophin knockout mdx (uko/mdx mice. Uko/mdx mice display severe clinical symptoms and die prematurely as in Duchenne muscular dystrophy (DMD patients. Here we tested the hypothesis that marginal level dystrophin expression may improve the clinical outcome of uko/mdx mice. It is well established that mdx3cv (3cv mice express a near-full length dystrophin protein at ∼5% of the normal level. We crossed utrophin-null mutation to the 3cv background. The resulting uko/3cv mice expressed the same level of dystrophin as 3cv mice but utrophin expression was completely eliminated. Surprisingly, uko/3cv mice showed a much milder phenotype. Compared to uko/mdx mice, uko/3cv mice had significantly higher body weight and stronger specific muscle force. Most importantly, uko/3cv outlived uko/mdx mice by several folds. Our results suggest that a threshold level dystrophin expression may provide vital clinical support in a severely affected DMD mouse model. This finding may hold clinical implications in developing novel DMD therapies.

Constitutive expression of tert in thymocytes leads to increased incidence and dissemination of T-cell lymphoma in Lck-Tert mice.

Science.gov (United States)

Canela, Andrés; Martín-Caballero, Juan; Flores, Juana M; Blasco, María A

2004-05-01

Here we describe a new mouse model with constitutive expression of the catalytic subunit of telomerase (Tert) targeted to thymocytes and peripheral T cells (Lck-Tert mice). Two independent Lck-Tert mouse lines showed higher incidences of spontaneous T-cell lymphoma than the corresponding age-matched wild-type controls, indicating that constitutive expression of Tert promotes lymphoma. Interestingly, T-cell lymphomas in Lck-Tert mice were more disseminated than those in wild-type controls and affected both lymphoid and nonlymphoid tissues, while nonlymphoid tissues were never affected with lymphoma in age-matched wild-type controls. Importantly, these roles of Tert constitutive expression in promoting tumor progression and dissemination were independent of the role of telomerase in telomere length maintenance, since telomere length distributions on a single-cell basis were identical in Lck-Tert and wild-type thymocytes. Finally, Tert constitutive expression did not interfere with telomere capping in Lck-Tert primary thymocytes, although it resulted in greater chromosomal instability upon gamma irradiation in Lck-Tert primary lymphocytes than in controls, suggesting that Tert overexpression may interfere with the cellular response to DNA damage.

Transgenic Expression of Dspp Partially Rescued the Long Bone Defects of Dmp1-null Mice

Science.gov (United States)

Jani, Priyam H.; Gibson, Monica P.; Liu, Chao; Zhang, Hua; Wang, Xiaofang; Lu, Yongbo; Qin, Chunlin

2016-01-01

Dentin matrix protein 1 (DMP1) and dentin sialophosphoprotein (DSPP) belong to the Small Integrin-Binding Ligand N-linked Glycoprotein (SIBLING) family. In addition to the features common to all SIBLING members, DMP1 and DSPP share several unique similarities in chemical structure, proteolytic activation and tissue localization. Mutations in, or deletion of DMP1, cause autosomal recessive hypophosphatemic rickets along with dental defects; DSPP mutations or its ablation are associated with dentinogenesis imperfecta. While the roles and functional mechanisms of DMP1 in osteogenesis have been extensively studied, those of DSPP in long bones have been studied only to a limited extent. Previous studies by our group revealed that transgenic expression of Dspp completely rescued the dentin defects of Dmp1-null (Dmp1−/−) mice. In this investigation, we assessed the effects of transgenic Dspp on osteogenesis by analyzing the formation and mineralization of the long bones in Dmp1−/− mice that expresses a transgene encoding full-length DSPP driven by a 3.6-kb rat Col1a1 promoter (referred as “Dmp1−/−;Dspp-Tg mice”). We characterized the long bones of the Dmp1−/−;Dspp-Tg mice at different ages and compared them with those from Dmp1−/− and Dmp1+/− (normal control) mice. Our analyses showed that the long bones of Dmp1−/−;Dspp-Tg mice had a significant increase in cortical bone thickness, bone volume and mineral density along with a remarkable restoration of trabecular thickness compared to those of the Dmp1−/− mice. The long bones of Dmp1−/−;Dspp-Tg mice underwent a dramatic reduction in the amount of osteoid, significant improvement of the collagen fibrillar network, and better organization of the lacunocanalicular system, compared to the Dmp1−/− mice. The elevated levels of biglycan, bone sialoprotein and osteopontin in Dmp1−/− mice were also noticeably corrected by the transgenic expression of Dspp. These findings suggest that

Age-related deterioration of rod vision in mice.

Science.gov (United States)

Kolesnikov, Alexander V; Fan, Jie; Crouch, Rosalie K; Kefalov, Vladimir J

2010-08-18

Even in healthy individuals, aging leads to deterioration in visual acuity, contrast sensitivity, visual field, and dark adaptation. Little is known about the neural mechanisms that drive the age-related changes of the retina and, more specifically, photoreceptors. According to one hypothesis, the age-related deterioration in rod function is due to the limited availability of 11-cis-retinal for rod pigment formation. To determine how aging affects rod photoreceptors and to test the retinoid-deficiency hypothesis, we compared the morphological and functional properties of rods of adult and aged B6D2F1/J mice. We found that the number of rods and the length of their outer segments were significantly reduced in 2.5-year-old mice compared with 4-month-old animals. Aging also resulted in a twofold reduction in the total level of opsin in the retina. Behavioral tests revealed that scotopic visual acuity and contrast sensitivity were decreased by twofold in aged mice, and rod ERG recordings demonstrated reduced amplitudes of both a- and b-waves. Sensitivity of aged rods determined from single-cell recordings was also decreased by 1.5-fold, corresponding to not more than 1% free opsin in these photoreceptors, and kinetic parameters of dim flash response were not altered. Notably, the rate of rod dark adaptation was unaffected by age. Thus, our results argue against age-related deficiency of 11-cis-retinal in the B6D2F1/J mouse rod visual cycle. Surprisingly, the level of cellular dark noise was increased in aged rods, providing an alternative mechanism for their desensitization.

Aging-associated oxidative stress inhibits liver progenitor cell activation in mice.

Science.gov (United States)

Cheng, Yiji; Wang, Xue; Wang, Bei; Zhou, Hong; Dang, Shipeng; Shi, Yufang; Hao, Li; Luo, Qingquan; Jin, Min; Zhou, Qianjun; Zhang, Yanyun

2017-04-29

Recent studies have discovered aging-associated changes of adult stem cells in various tissues and organs, which potentially contribute to the organismal aging. However, aging-associated changes of liver progenitor cells (LPCs) remain elusive. Employing young (2-month-old) and old (24-month-old) mice, we found diverse novel alterations in LPC activation during aging. LPCs in young mice could be activated and proliferate upon liver injury, whereas the counterparts in old mice failed to respond and proliferate, leading to the impaired liver regeneration. Surprisingly, isolated LPCs from young and old mice did not exhibit significant difference in their clonogenic and proliferative capacity. Later, we uncovered that the decreased activation and proliferation of LPCs were due to excessive reactive oxygen species produced by neutrophils infiltrated into niche, which was resulted from chemokine production from activated hepatic stellate cells during aging. This study demonstrates aging-associated changes in LPC activation and reveals critical roles for the stem cell niche, including neutrophils and hepatic stellate cells, in the negative regulation of LPCs during aging.

Effects of aging and uninephrectomy on renal changes in Tsukuba hypertensive mice.

Science.gov (United States)

Inui, Yosuke; Mochida, Hideki; Yamairi, Fumiko; Okada, Miyoko; Ishida, Junji; Fukamizu, Akiyoshi; Arakawa, Kenji

2013-05-01

Renal dysfunction is accelerated by various factors such as hypertension, aging and diabetes. Glomerular hyper-filtration, considered one of the major risk factors leading to diabetic nephropathy, is often encountered in diabetic patients. However, the interrelationship of these risk factors during the course and development of renal dysfunction has not been fully elucidated. In this study, the effects of aging and uninephrectomy (UNx)-induced hyperfiltration on renal changes were investigated in Tsukuba hypertensive mice (THM) carrying both human renin and angiotensinogen genes. In THM, the urinary albumin/creatinine (Alb/Cr) ratio was elevated with age without a concomitant increase in the plasma Cr concentration. Moreover, the urinary neutrophil gelatinase-associated lipocalin/Cr (NGAL/Cr) ratio, the renal monocyte chemoattractant protein-1 (MCP-1) mRNA expression and the renal collagen type I α 2 (COL1A2) mRNA expression were also increased with age. Age-related albuminuria in THM is likely caused by renal tubular damage, enhanced inflammatory response and tubulointerstitial fibrosis. Furthermore, following UNx, the urinary Alb/Cr ratio and the plasma Cr concentration were increased in THM. The urinary NGAL/Cr ratio and the renal MCP-1 and COL1A2 mRNA expression were not affected by UNx. These results suggested that UNx-induced albuminuria in THM was caused by glomerular dysfunction, rather than renal tubular injury. In conclusion, this study demonstrated for the first time the effects of aging and UNx on renal changes in THM. These findings strongly reinforce the significance of applying a diversity of therapeutic approaches to the management of renal dysfunction.

Vascular endothelial growth factor-D over-expressing tumor cells induce differential effects on uterine vasculature in a mouse model of endometrial cancer

Directory of Open Access Journals (Sweden)

Stacker Steven A

2010-07-01

Full Text Available Abstract Background It has been hypothesised that increased VEGF-D expression may be an independent prognostic factor for endometrial cancer progression and lymph node metastasis; however, the mechanism by which VEGF-D may promote disease progression in women with endometrial cancer has not been investigated. Our aim was to describe the distribution of lymphatic vessels in mouse uterus and to examine the effect of VEGF-D over-expression on these vessels in a model of endometrial cancer. We hypothesised that VEGF-D over-expression would stimulate growth of new lymphatic vessels into the endometrium, thereby contributing to cancer progression. Methods We initially described the distribution of lymphatic vessels (Lyve-1, podoplanin, VEGFR-3 and VEGF-D expression in the mouse uterus during the estrous cycle, early pregnancy and in response to estradiol-17beta and progesterone using immunohistochemistry. We also examined the effects of VEGF-D over-expression on uterine vasculature by inoculating uterine horns in NOD SCID mice with control or VEGF-D-expressing 293EBNA tumor cells. Results Lymphatic vessels positive for the lymphatic endothelial cell markers Lyve-1, podoplanin and VEGFR-3 profiles were largely restricted to the connective tissue between the myometrial circular and longitudinal muscle layers; very few lymphatic vessel profiles were observed in the endometrium. VEGF-D immunostaining was present in all uterine compartments (epithelium, stroma, myometrium, although expression was generally low. VEGF-D immunoexpression was slightly but significantly higher in estrus relative to diestrus; and in estradiol-17beta treated mice relative to vehicle or progesterone treated mice. The presence of VEGF-D over-expressing tumor cells did not induce endometrial lymphangiogenesis, although changes were observed in existing vessel profiles. For myometrial lymphatic and endometrial blood vessels, the percentage of profiles containing proliferating

Long-term Neuroglial Cocultures as a Brain Aging Model: Hallmarks of Senescence, MicroRNA Expression Profiles, and Comparison With In Vivo Models.

Science.gov (United States)

Bigagli, Elisabetta; Luceri, Cristina; Scartabelli, Tania; Dolara, Piero; Casamenti, Fiorella; Pellegrini-Giampietro, Domenico E; Giovannelli, Lisa

2016-01-01

Our purpose was to evaluate long-term neuroglial cocultures as a model for investigating senescence in the nervous system and to assess its similarities with in vivo models. To this aim, we maintained the cultures from 15 days in vitro (mature cultures) up to 27 days in vitro (senescent cultures), measuring senescence-associated, neuronal, dendritic, and astrocytic markers. Whole microRNA expression profiles were compared with those measured in the cortex of 18- and 24-month-old C57Bl/6J aged mice and of transgenic TgCRND8 mice, a model of amyloid-β deposition. Neuroglial cocultures displayed features of cellular senescence (increased senescence-associated-β-galactosidase activity, oxidative stress, γ-H2AX expression, IL-6 production, astrogliosis) that were concentration dependently counteracted by the antiaging compound resveratrol (1-5 µM). Among the 1,080 microRNAs analyzed, 335 were downregulated or absent in 27 compared with 15 days in vitro and resveratrol reversed this effect. A substantial overlapping was found between age-associated changes in microRNA expression profiles in vitro and in TgCRND8 mice but not in physiologically aged mice, indicating that this culture model displays more similarities with pathological than physiological brain aging. Our results demonstrate that neuroglial cocultures aged in vitro can be useful for investigating the cellular and molecular mechanisms of brain aging and for preliminary testing of protective compounds. © The Author 2015. 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.

Effects of aging and calorie restriction on the global gene expression profiles of mouse testis and ovary

Directory of Open Access Journals (Sweden)

Longo Dan L

2008-06-01

Full Text Available Abstract Background The aging of reproductive organs is not only a major social issue, but of special interest in aging research. A long-standing view of 'immortal germ line versus mortal soma' poses an important question of whether the reproductive tissues age in similar ways to the somatic tissues. As a first step to understand this phenomenon, we examine global changes in gene expression patterns by DNA microarrays in ovaries and testes of C57BL/6 mice at 1, 6, 16, and 24 months of age. In addition, we compared a group of mice on ad libitum (AL feeding with a group on lifespan-extending 40% calorie restriction (CR. Results We found that gene expression changes occurred in aging gonads, but were generally different from those in somatic organs during aging. For example, only two functional categories of genes previously associated with aging in muscle, kidney, and brain were confirmed in ovary: genes associated with complement activation were upregulated, and genes associated with mitochondrial electron transport were downregulated. The bulk of the changes in gonads were mostly related to gonad-specific functions. Ovaries showed extensive gene expression changes with age, especially in the period when ovulation ceases (from 6 to 16 months, whereas testes showed only limited age-related changes. The same trend was seen for the effects of CR: CR-mediated reversal of age-associated gene expression changes, reported in somatic organs previously, was limited to a small number of genes in gonads. Instead, in both ovary and testis, CR caused small and mostly gonad-specific effects: suppression of ovulation in ovary and activation of testis-specific genes in testis. Conclusion Overall, the results are consistent with unique modes of aging and its modification by CR in testis and ovary.

A novel radial water tread maze tracks age-related cognitive decline in mice

Directory of Open Access Journals (Sweden)

Christina Pettan-Brewer

2013-10-01

Full Text Available There is currently no treatment and cure for age-related dementia and cognitive impairment in humans. Mice suffer from age-related cognitive decline just as people do, but assessment is challenging because of cumbersome and at times stressful performance tasks. We developed a novel radial water tread (RWT maze and tested male C57BL/6 (B6 and C57BL/6 x Balb/c F1 (CB6F1 mice at ages 4, 12, 20, and 28 months. B6 mice showed a consistent learning experience and memory retention that gradually decreased with age. CB6F1 mice showed a moderate learning experience in the 4 and 12 month groups, which was not evident in the 20 and 28 month groups. In conclusion, CB6F1 mice showed more severe age-related cognitive impairment compared to B6 mice and might be a suitable model for intervention studies. In addition, the RWT maze has a number of operational advantages compared to currently accepted tasks and can be used to assess age-related cognition impairment in B6 and CB6F1 mice as early as 12 months of age.

Dendrobium nobile Lindl. alkaloids regulate metabolism gene expression in livers of mice.

Science.gov (United States)

Xu, Yun-Yan; Xu, Ya-Sha; Wang, Yuan; Wu, Qin; Lu, Yuan-Fu; Liu, Jie; Shi, Jing-Shan

2017-10-01

In our previous studies, Dendrobium nobile Lindl. alkaloids (DNLA) has been shown to have glucose-lowering and antihyperlipidaemia effects in diabetic rats, in rats fed with high-fat diets, and in mice challenged with adrenaline. This study aimed to examine the effects of DNLA on the expression of glucose and lipid metabolism genes in livers of mice. Mice were given DNLA at doses of 10-80 mg/kg, po for 8 days, and livers were removed for total RNA and protein isolation to perform real-time RT-PCR and Western blot analysis. Dendrobium nobile Lindl. alkaloids increased PGC1α at mRNA and protein levels and increased glucose metabolism gene Glut2 and FoxO1 expression. DNLA also increased the expression of fatty acid β-oxidation genes Acox1 and Cpt1a. The lipid synthesis regulator Srebp1 (sterol regulatory element-binding protein-1) was decreased, while the lipolysis gene ATGL was increased. Interestingly, DNLA increased the expression of antioxidant gene metallothionein-1 and NADPH quinone oxidoreductase-1 (Nqo1) in livers of mice. Western blot on selected proteins confirmed these changes including the increased expression of GLUT4 and PPARα. DNLA has beneficial effects on liver glucose and lipid metabolism gene expressions, and enhances the Nrf2-antioxidant pathway gene expressions, which could play integrated roles in regulating metabolic disorders. © 2017 Royal Pharmaceutical Society.

Expression of MDM2 in an acute lymphocytic leukemia mice model induced by γ-radiation

International Nuclear Information System (INIS)

Huang Yuecheng; Cai Jianming; Han Ling; Gao Fu; Cui Jianguo; Gao Jianguo

2004-01-01

Objective: To investigate the role of the MDM 2 in the process of carcinogenesis induced by γ-rays and its molecular mechanisms. Methods: Animal model of radiation-induced leukemia was established by γ-irradiation. According to the histological and morphological results, mice tissues were divided into three groups: cancerization group, incancerization group and control group. Expression of MDM 2 protein and mRNA in thymus/bone marrow was detected with Western blot and in situ hybridization (ISH), respectively. The authors also examined the protein phosphorylation level of MDM 2 protein by immunoprecipitation (IP). PCR-SSCP was performed to detect gene mutation. Results: A mice leukemia model was successfully established as verified by pathological findings and confirmed by transplantation test in nude mice. The protein expression in thymus/bone marrow in irradiation groups was significantly higher than that in controls (P 2 was found to be hyper-phosphorylated in the cancerization group as compared with other groups. No gene mutation was detected by SSCP/silver-staining assay in the tumor samples. Conclusion: MDM 2 may be involved in the development and progression of leukemia induced by γ-irradiation. The over-expression but not gene mutation may be responsible for malignant transformation induced by radiation. Phosphorylation is at least partly attributed to activation of MDM 2

Neuronal erythropoietin overexpression protects mice against age-related hearing loss (presbycusis).

Science.gov (United States)

Monge Naldi, Arianne; Belfrage, Celina; Jain, Neha; Wei, Eric T; Canto Martorell, Belén; Gassmann, Max; Vogel, Johannes

2015-12-01

So far, typical causes of presbycusis such as degeneration of hair cells and/or primary auditory (spiral ganglion) neurons cannot be treated. Because erythropoietin's (Epo) neuroprotective potential has been shown previously, we determined hearing thresholds of juvenile and aged mice overexpressing Epo in neuronal tissues. Behavioral audiometry revealed in contrast to 5 months of age, that 11-month-old Epo-transgenic mice had up to 35 dB lower hearing thresholds between 1.4 and 32 kHz, and at the highest frequencies (50-80 kHz), thresholds could be obtained in aged Epo-transgenic only but not anymore in old C57BL6 control mice. Click-evoked auditory brainstem response showed similar results. Numbers of spiral ganglion neurons in aged C57BL6 but not Epo-transgenic mice were dramatically reduced mainly in the basal turn, the location of high frequencies. In addition, there was a tendency to better preservation of inner and outer hair cells in Epo-transgenic mice. Hence, Epo's known neuroprotective action effectively suppresses the loss of spiral ganglion cells and probably also hair cells and, thus, development of presbycusis in mice. Copyright © 2015 Elsevier Inc. All rights reserved.

Intake of Wild Blueberry Powder Improves Episodic-Like and Working Memory during Normal Aging in Mice.

Science.gov (United States)

Beracochea, Daniel; Krazem, Ali; Henkouss, Nadia; Haccard, Guillaume; Roller, Marc; Fromentin, Emilie

2016-08-01

The number of Americans older than 65 years old is projected to more than double in the next 40 years. Cognitive changes associated to aging can affect an adult's day-to-day functioning. Among these cognitive changes, reasoning, episodic memory, working memory, and processing speed decline gradually over time. Early memory changes include a decline in both working and episodic memory. The aim of the present study was to determine whether chronic (up to 75 days) daily administration of wild blueberry extract or a wild blueberry full spectrum powder would help prevent memory failure associated with aging in tasks involving various forms of memory. Both blueberry ingredients were used in a study comparing young mice (6 months old) to aged mice (18 months old). At this age, mice exhibit memory decline due to aging, which is exacerbated first by a loss in working and contextual (episodic-like) memory. Contextual memory (episodic-like memory) was evaluated using the contextual serial discrimination test. Working and spatial memory were evaluated using the Morris-Water maze test and the sequential alternation test. Statistical analysis was performed using an ANOVA with the Bonferroni post-hoc test. Supplementation with wild blueberry full spectrum powder and wild blueberry extract resulted in significant improvement of contextual memory, while untreated aged mice experienced a decline in such memory. Only the wild blueberry full spectrum powder significantly contributed to an improvement of spatial and working memory versus untreated aged mice. These improvements of cognitive performance may be related to brain oxidative status, acetylcholinesterase activity, neuroprotection, or attenuation of immunoreactivity. Georg Thieme Verlag KG Stuttgart · New York.

Rate of lens lesion development and the age of mice at time of irradiation

International Nuclear Information System (INIS)

Gajewski, A.K.; Majewska, K.; Slowikowska, M.G.

1976-01-01

The rate of lens lesion development has been studied in mice irradiated at different age ranging from one day up to one year old mice. The time needed for the first appearance of lens lesion was shortest in groups of mice irradiated at the age of one, two and three days of life, and longest in groups of mice irradiated at the age of 5 days, 1 week and 2 weeks of life. The time needed for the first appearance of lens lesion for mice irradiated between the third week and one year of life was constant. It was longer than for mice irradiated during the first three days of life and shorter than for mice irradiated at 5 up to 14 days of life. In all but one irradiated groups the age at which the first lens lesion occurred differed significantly from the age at which the first senile changes occurred in the lens of control mice. The one exception was the group of mice irradiated at the age of one year. (author)

Age-related changes in mouse taste bud morphology, hormone expression, and taste responsivity.

Science.gov (United States)

Shin, Yu-Kyong; Cong, Wei-na; Cai, Huan; Kim, Wook; Maudsley, Stuart; Egan, Josephine M; Martin, Bronwen

2012-04-01

Normal aging is a complex process that affects every organ system in the body, including the taste system. Thus, we investigated the effects of the normal aging process on taste bud morphology, function, and taste responsivity in male mice at 2, 10, and 18 months of age. The 18-month-old animals demonstrated a significant reduction in taste bud size and number of taste cells per bud compared with the 2- and 10-month-old animals. The 18-month-old animals exhibited a significant reduction of protein gene product 9.5 and sonic hedgehog immunoreactivity (taste cell markers). The number of taste cells expressing the sweet taste receptor subunit, T1R3, and the sweet taste modulating hormone, glucagon-like peptide-1, were reduced in the 18-month-old mice. Concordant with taste cell alterations, the 18-month-old animals demonstrated reduced sweet taste responsivity compared with the younger animals and the other major taste modalities (salty, sour, and bitter) remained intact.

Paternal Aging Affects Behavior in Pax6 Mutant Mice: A Gene/Environment Interaction in Understanding Neurodevelopmental Disorders.

Science.gov (United States)

Yoshizaki, Kaichi; Furuse, Tamio; Kimura, Ryuichi; Tucci, Valter; Kaneda, Hideki; Wakana, Shigeharu; Osumi, Noriko

2016-01-01

Neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention deficit and hyperactivity disorder (ADHD) have increased over the last few decades. These neurodevelopmental disorders are characterized by a complex etiology, which involves multiple genes and gene-environmental interactions. Various genes that control specific properties of neural development exert pivotal roles in the occurrence and severity of phenotypes associated with neurodevelopmental disorders. Moreover, paternal aging has been reported as one of the factors that contribute to the risk of ASD and ADHD. Here we report, for the first time, that paternal aging has profound effects on the onset of behavioral abnormalities in mice carrying a mutation of Pax6, a gene with neurodevelopmental regulatory functions. We adopted an in vitro fertilization approach to restrict the influence of additional factors. Comprehensive behavioral analyses were performed in Sey/+ mice (i.e., Pax6 mutant heterozygotes) born from in vitro fertilization of sperm taken from young or aged Sey/+ fathers. No body weight changes were found in the four groups, i.e., Sey/+ and wild type (WT) mice born to young or aged father. However, we found important differences in maternal separation-induced ultrasonic vocalizations of Sey/+ mice born from young father and in the level of hyperactivity of Sey/+ mice born from aged fathers in the open-field test, respectively, compared to WT littermates. Phenotypes of anxiety were observed in both genotypes born from aged fathers compared with those born from young fathers. No significant difference was found in social behavior and sensorimotor gating among the four groups. These results indicate that mice with a single genetic risk factor can develop different phenotypes depending on the paternal age. Our study advocates for serious considerations on the role of paternal aging in breeding strategies for animal studies.

Paternal Aging Affects Behavior in Pax6 Mutant Mice: A Gene/Environment Interaction in Understanding Neurodevelopmental Disorders.

Directory of Open Access Journals (Sweden)

Kaichi Yoshizaki

Full Text Available Neurodevelopmental disorders such as autism spectrum disorder (ASD and attention deficit and hyperactivity disorder (ADHD have increased over the last few decades. These neurodevelopmental disorders are characterized by a complex etiology, which involves multiple genes and gene-environmental interactions. Various genes that control specific properties of neural development exert pivotal roles in the occurrence and severity of phenotypes associated with neurodevelopmental disorders. Moreover, paternal aging has been reported as one of the factors that contribute to the risk of ASD and ADHD. Here we report, for the first time, that paternal aging has profound effects on the onset of behavioral abnormalities in mice carrying a mutation of Pax6, a gene with neurodevelopmental regulatory functions. We adopted an in vitro fertilization approach to restrict the influence of additional factors. Comprehensive behavioral analyses were performed in Sey/+ mice (i.e., Pax6 mutant heterozygotes born from in vitro fertilization of sperm taken from young or aged Sey/+ fathers. No body weight changes were found in the four groups, i.e., Sey/+ and wild type (WT mice born to young or aged father. However, we found important differences in maternal separation-induced ultrasonic vocalizations of Sey/+ mice born from young father and in the level of hyperactivity of Sey/+ mice born from aged fathers in the open-field test, respectively, compared to WT littermates. Phenotypes of anxiety were observed in both genotypes born from aged fathers compared with those born from young fathers. No significant difference was found in social behavior and sensorimotor gating among the four groups. These results indicate that mice with a single genetic risk factor can develop different phenotypes depending on the paternal age. Our study advocates for serious considerations on the role of paternal aging in breeding strategies for animal studies.

RNA sequencing reveals differential expression of mitochondrial and oxidation reduction genes in the long-lived naked mole-rat when compared to mice.

Science.gov (United States)

Yu, Chuanfei; Li, Yang; Holmes, Andrew; Szafranski, Karol; Faulkes, Chris G; Coen, Clive W; Buffenstein, Rochelle; Platzer, Matthias; de Magalhães, João Pedro; Church, George M

2011-01-01

The naked mole-rat (Heterocephalus glaber) is a long-lived, cancer resistant rodent and there is a great interest in identifying the adaptations responsible for these and other of its unique traits. We employed RNA sequencing to compare liver gene expression profiles between naked mole-rats and wild-derived mice. Our results indicate that genes associated with oxidoreduction and mitochondria were expressed at higher relative levels in naked mole-rats. The largest effect is nearly 300-fold higher expression of epithelial cell adhesion molecule (Epcam), a tumour-associated protein. Also of interest are the protease inhibitor, alpha2-macroglobulin (A2m), and the mitochondrial complex II subunit Sdhc, both ageing-related genes found strongly over-expressed in the naked mole-rat. These results hint at possible candidates for specifying species differences in ageing and cancer, and in particular suggest complex alterations in mitochondrial and oxidation reduction pathways in the naked mole-rat. Our differential gene expression analysis obviated the need for a reference naked mole-rat genome by employing a combination of Illumina/Solexa and 454 platforms for transcriptome sequencing and assembling transcriptome contigs of the non-sequenced species. Overall, our work provides new research foci and methods for studying the naked mole-rat's fascinating characteristics.

RNA sequencing reveals differential expression of mitochondrial and oxidation reduction genes in the long-lived naked mole-rat when compared to mice.

Directory of Open Access Journals (Sweden)

Chuanfei Yu

Full Text Available The naked mole-rat (Heterocephalus glaber is a long-lived, cancer resistant rodent and there is a great interest in identifying the adaptations responsible for these and other of its unique traits. We employed RNA sequencing to compare liver gene expression profiles between naked mole-rats and wild-derived mice. Our results indicate that genes associated with oxidoreduction and mitochondria were expressed at higher relative levels in naked mole-rats. The largest effect is nearly 300-fold higher expression of epithelial cell adhesion molecule (Epcam, a tumour-associated protein. Also of interest are the protease inhibitor, alpha2-macroglobulin (A2m, and the mitochondrial complex II subunit Sdhc, both ageing-related genes found strongly over-expressed in the naked mole-rat. These results hint at possible candidates for specifying species differences in ageing and cancer, and in particular suggest complex alterations in mitochondrial and oxidation reduction pathways in the naked mole-rat. Our differential gene expression analysis obviated the need for a reference naked mole-rat genome by employing a combination of Illumina/Solexa and 454 platforms for transcriptome sequencing and assembling transcriptome contigs of the non-sequenced species. Overall, our work provides new research foci and methods for studying the naked mole-rat's fascinating characteristics.

Gene expression in the aging human brain: an overview.

Science.gov (United States)

Mohan, Adith; Mather, Karen A; Thalamuthu, Anbupalam; Baune, Bernhard T; Sachdev, Perminder S

2016-03-01

The review aims to provide a summary of recent developments in the study of gene expression in the aging human brain. Profiling differentially expressed genes or 'transcripts' in the human brain over the course of normal aging has provided valuable insights into the biological pathways that appear activated or suppressed in late life. Genes mediating neuroinflammation and immune system activation in particular, show significant age-related upregulation creating a state of vulnerability to neurodegenerative and neuropsychiatric disease in the aging brain. Cellular ionic dyshomeostasis and age-related decline in a host of molecular influences on synaptic efficacy may underlie neurocognitive decline in later life. Critically, these investigations have also shed light on the mobilization of protective genetic responses within the aging human brain that help determine health and disease trajectories in older age. There is growing interest in the study of pre and posttranscriptional regulators of gene expression, and the role of noncoding RNAs in particular, as mediators of the phenotypic diversity that characterizes human brain aging. Gene expression studies in healthy brain aging offer an opportunity to unravel the intricately regulated cellular underpinnings of neurocognitive aging as well as disease risk and resiliency in late life. In doing so, new avenues for early intervention in age-related neurodegenerative disease could be investigated with potentially significant implications for the development of disease-modifying therapies.

[Effects of aquaporin-4 gene knockout on behavior changes and cerebral morphology during aging in mice].

Science.gov (United States)

Su, Shengan; Lu, Yunbi; Zhang, Weiping

2013-05-01

To investigate the effects of aquaporin-4 (AQP4) gene knockout on the behavior changes and cerebral morphology during aging in mice,and to compare that of young and aged mice between AQP4 knockout mice (AQP4(-/-)) and wild type mice (AQP4(+/+)). Fifty-eight CD-1 mice were divided into four groups: young (2-3 months old) AQP4(-/-), aged (17-19 months old) AQP4(-/-), young AQP4(+/+) and aged AQP4(+/+). The activity levels and exploring behavior of mice were tested in open field. The neurons were stained with toluidine blue and NeuN, the astrocytes and microglia were stained with GFAP and Iba-1, respectively. The morphological changes of neuron, astrocyte and microglia were then analyzed. Compared with young mice, the total walking distance in open field of aged AQP4(+/+) mice and aged AQP4(-/-) mice decreased 41.2% and 44.1%, respectively (Ptime in the central area of open field. The density of neuron in cortex of aged AQP4(+/+) mice and aged AQP4(-/-) mice decreased 19.6% and 15.8%, respectively (P<0.05), while there was no difference in the thickness of neuron cell body in hippocampus CA1 region. The density of astrocyte in hippocampus CA3 region of aged AQP4(+/+) mice and aged AQP4(-/-) mice increased 57.7% and 64.3%, respectively (P<0.001), while there was no difference in the area of astrocyte. The area of microglia in hippocampus CA3 region of aged AQP4(+/+) mice and aged AQP4(-/-) mice increased 46.9% and 52.0%, respectively (P<0.01), while there was no difference in the density of microglia. Compared with AQP4(+/+) mice, the young and aged AQP4(-/-) mice showed smaller area of astrocyte in hippocampus CA3 region, reduced 18.0% in young mice and 23.6% in aged mice. There was no difference between AQP4(+/+) mice and AQP4(-/-) mice for other observed indexes. AQP4 may be involved in change of astrocyte and astrocyte-related behaviors during aging. AQP4 gene knockout may have limited effects on the change of neuron, microglia and most neuronal behaviors in aging

Diabetes-Resistant NOR Mice Are More Severely Affected by Streptozotocin Compared to the Diabetes-Prone NOD Mice: Correlations with Liver and Kidney GLUT2 Expressions

Directory of Open Access Journals (Sweden)

S. Kahraman

2015-01-01

Full Text Available Nonobese Diabetic (NOD mice are susceptible strains for Type 1 diabetes development, and Nonobese Diabetes-Resistant (NOR mice are defined as suitable controls for NOD mice in non-MHC-related research. Diabetes is often accelerated in NOD mice via Streptozotocin (STZ. STZ is taken inside cells via GLUT2 transmembrane carrier proteins, the major glucose transporter isoforms in pancreatic beta cells, liver, kidneys, and the small intestine. We observed severe adverse effects in NOR mice treated with STZ compared to NOD mice that were made diabetic with a similar dose. We suggested that the underlying mechanism could be differential GLUT2 expressions in pancreatic beta cells, yet immunofluorescent and immunohistochemical studies revealed similar GLUT2 expression levels. We also detected GLUT2 expression profiles in NOD and NOR hepatic and renal tissues by western blot analysis and observed considerably higher GLUT2 expression levels in liver and kidney tissues of NOR mice. Although beta cell GLUT2 expression levels are frequently evaluated as a marker predicting STZ sensitivity in animal models, we report here very different diabetic responses to STZ in two different animal strains, in spite of similar initial GLUT2 expressions in beta cells. Furthermore, use of NOR mice in STZ-mediated experimental diabetes settings should be considered accordingly.

Chronic treatment with ginsenoside Rg1 promotes memory and hippocampal long-term potentiation in middle-aged mice.

Science.gov (United States)

Zhu, G; Wang, Y; Li, J; Wang, J

2015-04-30

Ginseng serves as a potential candidate for the treatment of aging-related memory decline or memory loss. However, the related mechanism is not fully understood. In this study, we applied an intraperitoneal injection of ginsenoside Rg1, an active compound from ginseng in middle-aged mice and detected memory improvement and the underlying mechanisms. Our results showed that a period of 30-day administration of ginsenoside Rg1 enhanced long-term memory in the middle-aged animals. Consistent with the memory improvement, ginsenoside Rg1 administration facilitated weak theta-burst stimulation (TBS)-induced long-term potentiation (LTP) in acute hippocampal slices from middle-aged animals. Ginsenoside Rg1 administration increased the dendritic apical spine numbers and area in the CA1 region. In addition, ginsenoside Rg1 administration up-regulated the expression of hippocampal p-AKT, brain-derived neurotrophic factor (BDNF), proBDNF and glutamate receptor 1 (GluR1), but not p-ERK. Interestingly, the phosphatase and tensin homolog deleted on chromosome ten (PTEN) inhibitor (bpV) mimicked the ginsenoside Rg1 effects, including increasing p-AKT expression, promoting hippocampal basal synaptic transmission, LTP and memory. Taken together, our data suggest that ginsenoside Rg1 treatment improves memory in middle-aged mice possibly through regulating the PI3K/AKT pathway, altering apical spines and facilitating hippocampal LTP. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Motor Performance is Impaired Following Vestibular Stimulation in Ageing Mice

Science.gov (United States)

Tung, Victoria W. K.; Burton, Thomas J.; Quail, Stephanie L.; Mathews, Miranda A.; Camp, Aaron J.

2016-01-01

Balance and maintaining postural equilibrium are important during stationary and dynamic movements to prevent falls, particularly in older adults. While our sense of balance is influenced by vestibular, proprioceptive, and visual information, this study focuses primarily on the vestibular component and its age-related effects on balance. C57Bl/6J mice of ages 1, 5–6, 8–9 and 27–28 months were tested using a combination of standard (such as grip strength and rotarod) and newly-developed behavioral tests (including balance beam and walking trajectory tests with a vestibular stimulus). In the current study, we confirm a decline in fore-limb grip strength and gross motor coordination as age increases. We also show that a vestibular stimulus of low frequency (2–3 Hz) and duration can lead to age-dependent changes in balance beam performance, which was evident by increases in latency to begin walking on the beam as well as the number of times hind-feet slip (FS) from the beam. Furthermore, aged mice (27–28 months) that received continuous access to a running wheel for 4 weeks did not improve when retested. Mice of ages 1, 10, 13 and 27–28 months were also tested for changes in walking trajectory as a result of the vestibular stimulus. While no linear relationship was observed between the changes in trajectory and age, 1-month-old mice were considerably less affected than mice of ages 10, 13 and 27–28 months. Conclusion: this study confirms there are age-related declines in grip strength and gross motor coordination. We also demonstrate age-dependent changes to finer motor abilities as a result of a low frequency and duration vestibular stimulus. These changes showed that while the ability to perform the balance beam task remained intact across all ages tested, behavioral changes in task performance were observed. PMID:26869921

Markers of Alzheimer’s Disease in Primary Visual Cortex in Normal Aging in Mice

Directory of Open Access Journals (Sweden)

Luis Fernando Hernández-Zimbrón

2017-01-01

Full Text Available Aging is the principal risk factor for the development of Alzheimer’s disease (AD. The hallmarks of AD are accumulation of the amyloid-β peptide 1–42 (Aβ42 and abnormal hyperphosphorylation of Tau (p-Tau protein in different areas of the brain and, more recently reported, in the visual cortex. Recently, Aβ42 peptide overproduction has been involved in visual loss. Similar to AD, in normal aging, there is a significant amyloid deposition related to the overactivation of the aforementioned mechanisms. However, the mechanisms associated with visual loss secondary to age-induced visual cortex affectation are not completely understood. Young and aged mice were used as model to analyze the presence of Aβ42, p-Tau, glial-acidic fibrillary protein (GFAP, and presenilin-2, one of the main enzymes involved in Aβ42 production. Our results show a significant increase of Aβ42 deposition in aged mice in the following cells and/or tissues: endothelial cells and blood vessels and neurons of the visual cortex; they also show an increase of the expression of GFAP and presenilin-2 in this region. These results provide a comprehensive framework for the role of Aβ42 in visual loss due to inflammation present with aging and offer some clues for fruitful avenues for the study of healthy aging.

Expression of truncated PITX3 in the developing lens leads to microphthalmia and aphakia in mice.

Directory of Open Access Journals (Sweden)

Kenta Wada

Full Text Available Microphthalmia is a severe ocular disorder, and this condition is typically caused by mutations in transcription factors that are involved in eye development. Mice carrying mutations in these transcription factors would be useful tools for defining the mechanisms underlying developmental eye disorders. We discovered a new spontaneous recessive microphthalmos mouse mutant in the Japanese wild-derived inbred strain KOR1/Stm. The homozygous mutant mice were histologically characterized as microphthalmic by the absence of crystallin in the lens, a condition referred to as aphakia. By positional cloning, we identified the nonsense mutation c.444C>A outside the genomic region that encodes the homeodomain of the paired-like homeodomain transcription factor 3 gene (Pitx3 as the mutation responsible for the microphthalmia and aphakia. We examined Pitx3 mRNA expression of mutant mice during embryonic stages using RT-PCR and found that the expression levels are higher than in wild-type mice. Pitx3 over-expression in the lens during developmental stages was also confirmed at the protein level in the microphthalmos mutants via immunohistochemical analyses. Although lens fiber differentiation was not observed in the mutants, strong PITX3 protein signals were observed in the lens vesicles of the mutant lens. Thus, we speculated that abnormal PITX3, which lacks the C-terminus (including the OAR domain as a result of the nonsense mutation, is expressed in mutant lenses. We showed that the expression of the downstream genes Foxe3, Prox1, and Mip was altered because of the Pitx3 mutation, with large reductions in the lens vesicles in the mutants. Similar profiles were observed by immunohistochemical analysis of these proteins. The expression profiles of crystallins were also altered in the mutants. Therefore, we speculated that the microphthalmos/aphakia in this mutant is caused by the expression of truncated PITX3, resulting in the abnormal expression of

Expansion of myeloid-derived suppressor cells with aging in the bone marrow of mice through a NF-κB-dependent mechanism.

Science.gov (United States)

Flores, Rafael R; Clauson, Cheryl L; Cho, Joonseok; Lee, Byeong-Chel; McGowan, Sara J; Baker, Darren J; Niedernhofer, Laura J; Robbins, Paul D

2017-06-01

With aging, there is progressive loss of tissue homeostasis and functional reserve, leading to an impaired response to stress and an increased risk of morbidity and mortality. A key mediator of the cellular response to damage and stress is the transcription factor NF-κB. We demonstrated previously that NF-κB transcriptional activity is upregulated in tissues from both natural aged mice and in a mouse model of a human progeroid syndrome caused by defective repair of DNA damage (ERCC1-deficient mice). We also demonstrated that genetic reduction in the level of the NF-κB subunit p65(RelA) in the Ercc1 -/∆ progeroid mouse model of accelerated aging delayed the onset of age-related pathology including muscle wasting, osteoporosis, and intervertebral disk degeneration. Here, we report that the largest fraction of NF-κB -expressing cells in the bone marrow (BM) of aged (>2 year old) mice (C57BL/6-NF-κB EGFP reporter mice) are Gr-1 + CD11b + myeloid-derived suppressor cells (MDSCs). There was a significant increase in the overall percentage of MDSC present in the BM of aged animals compared with young, a trend also observed in the spleen. However, the function of these cells appears not to be compromised in aged mice. A similar increase of MDSC was observed in BM of progeroid Ercc1 -/∆ and BubR1 H/H mice. The increase in MDSC in Ercc1 -/∆ mice was abrogated by heterozygosity in the p65/RelA subunit of NF-κB. These results suggest that NF-κB activation with aging, at least in part, drives an increase in the percentage of MDSCs, a cell type able to suppress immune cell responses. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Ovarian transcriptome associated with reproductive senescence in the long-living Ames dwarf mice.

Science.gov (United States)

Schneider, Augusto; Matkovich, Scot J; Saccon, Tatiana; Victoria, Berta; Spinel, Lina; Lavasani, Mitra; Bartke, Andrzej; Golusinski, Pawel; Masternak, Michal M

2017-01-05

The aim of the current work was to evaluate the ovarian follicle reserve and the ovarian transcriptome in Ames dwarf (df/df) mice. The results suggest a delayed ovarian aging in df/df mice compared to normal (N) mice. Although a high number of genes were differentially expressed during aging of N mice, only a small fraction of these changed with aging in df/df mice. These alterations involved more than 500 categorized biological processes. The majority of these biological processes, including inflammatory/immune responses, were up-regulated with aging in N mice, while old df/df mice were characterized by down-regulation of these same processes in comparison to age matched N mice. However, biological processes related to DNA damage and repairing were commonly down-regulated with aging in both genotypes. In conclusion, delayed ovarian aging in long-living df/df mice was associated with reduced expression of genes related to the inflammatory and immune responses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Lymphocytes from wasted mice express enhanced spontaneous and {gamma}-ray-induced apoptosis

Energy Technology Data Exchange (ETDEWEB)

Woloschak, G.E. [Argonne National Lab., IL (United States)]|[Loyola Univ. Medical Center, Maywood, IL (United States); Chang-Liu, Chin-Mei [Argonne National Lab., IL (United States); Chung, Jen; Libertin, C.R. [Loyola Univ. Medical Center, Maywood, IL (United States)

1993-09-01

Mice bearing the autosomal recessive mutation wasted (wst/wst) display a disease pattern including faulty repair of DNA damage in lymphocytes after radiation exposure, neurologic abnormalities, and immunodeficiency. Many of the features of this mouse model have suggested a premature or increased spontaneous frequency of apoptosis in thymocytes; past work has shown an inability to establish cultured T cell lines, an abnormally high death rate of stimulated T cells in culture, and an increased sensitivity of T cells to the killing effects of ionizing radiations in wst/wst mice relative to controls. The experiments reported here were designed to examine splenic and thymic lymphocytes from wasted and control mice for signs of early apoptosis. Our results revealed enhanced expression of Rp-8 mRNA (associated with apoptosis) in thymic lymphocytes and reduced expression in splenic lymphocytes of wst/wst mice relative to controls; expression of Rp-2 and Td-30 mRNA (induced during apoptosis) were not detectable in spleen or thymus. Higher spontaneous DNA fragmentation was observed in wasted mice than in controls; however, {gamma}-ray-induced DNA fragmentation peaked at a lower dose and occurred to a greater extent in wasted mice relative to controls. These results provide evidence for high spontaneous and {gamma}-ray-induced apoptosis in T cells of wasted mice as a mechanism underlying the observed lymphocyte and DNA repair abnormalities.

Prenatal exposure to phencyclidine produces abnormal behaviour and NMDA receptor expression in postpubertal mice.

Science.gov (United States)

Lu, Lingling; Mamiya, Takayoshi; Lu, Ping; Toriumi, Kazuya; Mouri, Akihiro; Hiramatsu, Masayuki; Kim, Hyoung-Chun; Zou, Li-Bo; Nagai, Taku; Nabeshima, Toshitaka

2010-08-01

Several studies have shown the disruptive effects of non-competitive N-methyl-d-aspartate (NMDA) receptor antagonists on neurobehavioural development. Based on the neurodevelopment hypothesis of schizophrenia, there is growing interest in animal models treated with NMDA antagonists at developing stages to investigate the pathogenesis of psychological disturbances in humans. Previous studies have reported that perinatal treatment with phencyclidine (PCP) impairs the development of neuronal systems and induces schizophrenia-like behaviour. However, the adverse effects of prenatal exposure to PCP on behaviour and the function of NMDA receptors are not well understood. This study investigated the long-term effects of prenatal exposure to PCP in mice. The prenatal PCP-treated mice showed hypersensitivity to a low dose of PCP in locomotor activity and impairment of recognition memory in the novel object recognition test at age 7 wk. Meanwhile, the prenatal exposure reduced the phosphorylation of NR1, although it increased the expression of NR1 itself. Furthermore, these behavioural changes were attenuated by atypical antipsychotic treatment. Taken together, prenatal exposure to PCP produced long-lasting behavioural deficits, accompanied by the abnormal expression and dysfunction of NMDA receptors in postpubertal mice. It is worth investigating the influences of disrupted NMDA receptors during the prenatal period on behaviour in later life.

Loss of RhoB expression enhances the myelodysplastic phenotype of mammalian diaphanous-related Formin mDia1 knockout mice.

Directory of Open Access Journals (Sweden)

Aaron D DeWard

Full Text Available Myelodysplastic syndrome (MDS is characterized by ineffective hematopoiesis and hyperplastic bone marrow. Complete loss or interstitial deletions of the long arm of chromosome 5 occur frequently in MDS. One candidate tumor suppressor on 5q is the mammalian Diaphanous (mDia-related formin mDia1, encoded by DIAPH1 (5q31.3. mDia-family formins act as effectors for Rho-family small GTP-binding proteins including RhoB, which has also been shown to possess tumor suppressor activity. Mice lacking the Drf1 gene that encodes mDia1 develop age-dependent myelodysplastic features. We crossed mDia1 and RhoB knockout mice to test whether the additional loss of RhoB expression would compound the myelodysplastic phenotype. Drf1(-/-RhoB(-/- mice are fertile and develop normally. Relative to age-matched Drf1(-/-RhoB(+/- mice, the age of myelodysplasia onset was earlier in Drf1(-/-RhoB(-/- animals--including abnormally shaped erythrocytes, splenomegaly, and extramedullary hematopoiesis. In addition, we observed a statistically significant increase in the number of activated monocytes/macrophages in both the spleen and bone marrow of Drf1(-/-RhoB(-/- mice relative to Drf1(-/-RhoB(+/- mice. These data suggest a role for RhoB-regulated mDia1 in the regulation of hematopoietic progenitor cells.

A multi-ingredient dietary supplement abolishes large-scale brain cell loss, improves sensory function, and prevents neuronal atrophy in aging mice.

Science.gov (United States)

Lemon, J A; Aksenov, V; Samigullina, R; Aksenov, S; Rodgers, W H; Rollo, C D; Boreham, D R

2016-06-01

Transgenic growth hormone mice (TGM) are a recognized model of accelerated aging with characteristics including chronic oxidative stress, reduced longevity, mitochondrial dysfunction, insulin resistance, muscle wasting, and elevated inflammatory processes. Growth hormone/IGF-1 activate the Target of Rapamycin known to promote aging. TGM particularly express severe cognitive decline. We previously reported that a multi-ingredient dietary supplement (MDS) designed to offset five mechanisms associated with aging extended longevity, ameliorated cognitive deterioration and significantly reduced age-related physical deterioration in both normal mice and TGM. Here we report that TGM lose more than 50% of cells in midbrain regions, including the cerebellum and olfactory bulb. This is comparable to severe Alzheimer's disease and likely explains their striking age-related cognitive impairment. We also demonstrate that the MDS completely abrogates this severe brain cell loss, reverses cognitive decline and augments sensory and motor function in aged mice. Additionally, histological examination of retinal structure revealed markers consistent with higher numbers of photoreceptor cells in aging and supplemented mice. We know of no other treatment with such efficacy, highlighting the potential for prevention or amelioration of human neuropathologies that are similarly associated with oxidative stress, inflammation and cellular dysfunction. Environ. Mol. Mutagen. 57:382-404, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Effects of social isolation, re-socialization and age on cognitive and aggressive behaviors of Kunming mice and BALB/c mice.

Science.gov (United States)

An, Dong; Chen, Wei; Yu, De-Qin; Wang, Shi-Wei; Yu, Wei-Zhi; Xu, Hong; Wang, Dong-Mei; Zhao, Dan; Sun, Yi-Ping; Wu, Jun-Cheng; Tang, Yi-Yuan; Yin, Sheng-Ming

2017-05-01

Both Kunming (KM) mice and BALB/c mice have been widely used as rodent models to investigate stress-associated mental diseases. However, little is known about the different behaviors of KM mice and BALB/c mice after social isolation, particularly cognitive and aggressive behaviors. In this study, the behaviors of KM and BALB/c mice isolated for 2, 4 and 8 weeks and age-matched controls were evaluated using object recognition, object location and resident-intruder tests. The recovery of behavioral deficits by re-socialization was also examined for the isolated mice in adolescence. Our study showed that isolation for 2, 4 and 8 weeks led to cognitive deficits and increased aggressiveness for both KM and BALB/c mice. An important finding is that re-socialization could completely recover spatial/non-spatial cognitive deficits resulted from social isolation for both KM and BALB/c mice. In addition, age only impacted aggressiveness of KM mice. Moreover, isolation duration showed different impacts on cognitive and aggressive behaviors for both KM and BALB/c mice. Furthermore, BALB/c mice showed weak spatial/non-spatial memory and low aggressiveness when they were at the same age and isolation duration, compared to KM mice. In conclusion, KM mice and BALB/c mice behaved characteristically under physiology and isolation conditions. © 2016 Japanese Society of Animal Science.

Increased hypothalamic 5-HT2A receptor gene expression and effects of pharmacologic 5-HT2A receptor inactivation in obese Ay mice

International Nuclear Information System (INIS)

Nonogaki, Katsunori; Nozue, Kana; Oka, Yoshitomo

2006-01-01

Serotonin (5-hydroxytryptamine; 5-HT) 2A receptors contribute to the effects of 5-HT on platelet aggregation and vascular smooth muscle cell proliferation, and are reportedly involved in decreases in plasma levels of adiponectin, an adipokine, in diabetic subjects. Here, we report that systemic administration of sarpogrelate, a 5-HT2A receptor antagonist, suppressed appetite and increased hypothalamic pro-opiomelanocortin and cocaine- and amphetamine-regulated transcript, corticotropin releasing hormone, 5-HT2C, and 5-HT1B receptor gene expression. A y mice, which have ectopic expression of the agouti protein, significantly increased hypothalamic 5-HT2A receptor gene expression in association with obesity compared with wild-type mice matched for age. Systemic administration of sarpogrelate suppressed overfeeding, body weight gain, and hyperglycemia in obese A y mice, whereas it did not increase plasma adiponectin levels. These results suggest that obesity increases hypothalamic 5-HT2A receptor gene expression, and pharmacologic inactivation of 5-HT2A receptors inhibits overfeeding and obesity in A y mice, but did not increase plasma adiponectin levels

Spontaneous generation of rapidly transmissible prions in transgenic mice expressing wild-type bank vole prion protein.

Science.gov (United States)

Watts, Joel C; Giles, Kurt; Stöhr, Jan; Oehler, Abby; Bhardwaj, Sumita; Grillo, Sunny K; Patel, Smita; DeArmond, Stephen J; Prusiner, Stanley B

2012-02-28

Currently, there are no animal models of the most common human prion disorder, sporadic Creutzfeldt-Jakob disease (CJD), in which prions are formed spontaneously from wild-type (WT) prion protein (PrP). Interestingly, bank voles (BV) exhibit an unprecedented promiscuity for diverse prion isolates, arguing that bank vole PrP (BVPrP) may be inherently prone to adopting misfolded conformations. Therefore, we constructed transgenic (Tg) mice expressing WT BVPrP. Tg(BVPrP) mice developed spontaneous CNS dysfunction between 108 and 340 d of age and recapitulated the hallmarks of prion disease, including spongiform degeneration, pronounced astrogliosis, and deposition of alternatively folded PrP in the brain. Brain homogenates of ill Tg(BVPrP) mice transmitted disease to Tg(BVPrP) mice in ∼35 d, to Tg mice overexpressing mouse PrP in under 100 d, and to WT mice in ∼185 d. Our studies demonstrate experimentally that WT PrP can spontaneously form infectious prions in vivo. Thus, Tg(BVPrP) mice may be useful for studying the spontaneous formation of prions, and thus may provide insight into the etiology of sporadic CJD.

Circadian rhythm resynchronization improved isoflurane-induced cognitive dysfunction in aged mice.

Science.gov (United States)

Song, Jia; Chu, Shuaishuai; Cui, Yin; Qian, Yue; Li, Xiuxiu; Xu, Fangxia; Shao, Xueming; Ma, Zhengliang; Xia, Tianjiao; Gu, Xiaoping

2018-04-13

Postoperative cognitive dysfunction (POCD) is a common clinical phenomenon characterized by cognitive deficits in patients after anesthesia and surgery. Advanced age is a significant independent risk factor for POCD. We previously reported that in young mice, sleep-wake rhythm is involved in the isoflurane-induced memory impairment. In present study, we sought to determine whether advanced age increased the risk of POCD through aggravated and prolonged post-anesthetic circadian disruption in the elderly. We constructed POCD model by submitting the mice to 5-h 1.3% isoflurane anesthesia from Zeitgeber Time (ZT) 14 to ZT19. Under novel object recognition assay (NOR) and Morris water maze (MWM) test, We found 5-h isoflurane anesthesia impaired the cognition of young mice for early 3 days after anesthesia but damaged the aged for at least 1 week. With Mini-Mitter continuously monitoring, a 3.22 ± 0.75 h gross motor activity acrophase delay was manifested in young mice on D1, while in the aged mice, the gross motor activity phase shift lasted for 3 days, consistent with the body temperature rhythm trends of change. Melatonin has been considered as an effective remedy for circadian rhythm shift. In aged mice, melatonin was pretreated intragastrically at the dose of 10 mg/kg daily for 7 consecutive days before anesthesia. We found that melatonin prevented isoflurane-induced cognitive impairments by restoring the locomotor activity and temperature circadian rhythm via clock gene resynchronization. Overall, these results indicated that Long-term isoflurane anesthesia induced more aggravated and prolonged memory deficits and circadian rhythms disruption in aged mice. Melatonin could prevent isoflurane-induced cognitive impairments by circadian rhythm resynchronization. Copyright © 2018. Published by Elsevier Inc.

Effects of Aging and Oxidative Stress on Spermatozoa of Superoxide-Dismutase 1- and Catalase-Null Mice.

Science.gov (United States)

Selvaratnam, Johanna S; Robaire, Bernard

2016-09-01

Advanced paternal age is linked to complications in pregnancy and genetic diseases in offspring. Aging results in excess reactive oxygen species (ROS) and DNA damage in spermatozoa; this damage can be transmitted to progeny with detrimental consequences. Although there is a loss of antioxidants with aging, the impact on aging male germ cells of the complete absence of either catalase (CAT) or superoxide dismutase 1 (SOD1) has not been investigated. We used CAT-null (Cat(-/-)) and SOD1-null (Sod(-/-)) mice to determine whether loss of these antioxidants increases germ cell susceptibility to redox dysfunction with aging. Aging reduced fertility and the numbers of Sertoli and germ cells in all mice. Aged Sod(-/-) mice displayed an increased loss of fertility compared to aged wild-type mice. Treatment with the pro-oxidant SIN-10 increased ROS in spermatocytes of aged wild-type and Sod(-/-) mice, while aged Cat(-/-) mice were able to neutralize this ROS. The antioxidant peroxiredoxin 1 (PRDX1) increased with age in wild-type and Cat(-/-) mice but was consistently low in young and aged Sod(-/-) mice. DNA damage and repair markers (γ-H2AX and 53BP1) were reduced with aging and lower in young Sod(-/-) and Cat(-/-) mice. Colocalization of γ-H2AX and 53BP1 suggested active repair in young wild-type mice but reduced in young Cat(-/-) and in Sod(-/-) mice and with age. Oxidative DNA damage (8-oxodG) increased in young Sod(-/-) mice and with age in all mice. These studies show that aged Sod(-/-) mice display severe redox dysfunction, while wild-type and Cat(-/-) mice have compensatory mechanisms to partially alleviate oxidative stress and reduce age-related DNA damage in spermatozoa. Thus, SOD1 but not CAT is critical to the maintenance of germ cell quality with aging. © 2016 by the Society for the Study of Reproduction, Inc.

Age-Associated Decline in Thymic B Cell Expression of Aire and Aire-Dependent Self-Antigens

Directory of Open Access Journals (Sweden)

Sergio Cepeda

2018-01-01

Full Text Available Although autoimmune disorders are a significant source of morbidity and mortality in older individuals, the mechanisms governing age-associated increases in susceptibility remain incompletely understood. Central T cell tolerance is mediated through presentation of self-antigens by cells constituting the thymic microenvironment, including epithelial cells, dendritic cells, and B cells. Medullary thymic epithelial cells (mTECs and B cells express distinct cohorts of self-antigens, including tissue-restricted self-antigens (TRAs, such that developing T cells are tolerized to antigens from peripheral tissues. We find that expression of the TRA transcriptional regulator Aire, as well as Aire-dependent genes, declines with age in thymic B cells in mice and humans and that cell-intrinsic and cell-extrinsic mechanisms contribute to the diminished capacity of peripheral B cells to express Aire within the thymus. Our findings indicate that aging may diminish the ability of thymic B cells to tolerize T cells, revealing a potential mechanistic link between aging and autoimmunity.

CD44 and Bak expression in IL-6 or TNF-alpha gene knockout mice after whole lung irradiation

International Nuclear Information System (INIS)

Sakai, Minako; Iwakawa, Mayumi; Ohta, Toshie; Tsujii, Hirohiko; Imai, Takashi; Iwakura, Yoichiro

2008-01-01

To understand the molecular mechanisms that underlie radiation pneumonitis, we examined whether knockout of the tumor necrosis factor (TNF) or the interleukin (IL)-6 gene could give mice an inherent resistance to radiation in the acute phase of alveolar damage after thoracic irradiation. The temporal expression of inflammation (CD44) and apoptosis (Bak) markers in lung after thoracic irradiation was measured to determine the degree of alveolar damage. At 4 weeks post-irradiation (10 Gy), small inflammatory foci were observed in all mice, but there were no obvious histological differences between control (C57BL/6JSlc), TNF-alpha knockout (TNF KO), and IL-6 knockout (IL-6 KO) mice. However, immunohistochemical analysis of CD44 and Bak expression over a time course of 2 weeks highlighted significant differences between the three groups. C57BL/6JSlc and TNF KO mice had increased numbers of both CD44-positive and Bak-positive cells after irradiation, while the IL-6 KO mice showed stable levels of CD44 and Bak. In conclusion, the radioresistant status of IL-6 KO mice in the acute phase of alveolar damage after irradiation suggested an important role for IL-6 in radiation pneumonitis. (author)

Influence of aging and growth hormone on different members of the NFkB family and IkB expression in the heart from a murine model of senescence-accelerated aging.

Science.gov (United States)

Forman, K; Vara, E; García, C; Kireev, R; Cuesta, S; Acuña-Castroviejo, D; Tresguerres, J A F

2016-01-01

Inflammation is related to several pathological processes. The aim of this study was to investigate the protein expression of the different subunits of the nuclear factor Kappa b (NFkBp65, p50, p105, p52, p100) and the protein expressions of IkB beta and alpha in the hearts from a murine model of accelerated aging (SAM model) by Western blot. In addition, the translocation of some isoforms of NFkB from cytosol to nuclei (NFkBp65, p50, p52) and ATP level content was studied. In addition we investigated the effect of the chronic administration of growth hormone (GH) on these age-related parameters. SAMP8 and SAMR1 mice of 2 and 10 months of age were used (n = 30). Animals were divided into five experimental groups: 2 old untreated (SAMP8/SAMR1), 2 young control (SAMP8/SAMR1) and one GH treated-old groups (SAMP8). Age-related changes were found in the studied parameters. We were able to see decreases of ATP level contents and the translocation of the nuclear factor kappa B p50, p52 and p65 from cytosol to nuclei in old SAMP8 mice together with a decrease of IKB proteins. However p100 and p105 did not show differences with aging. No significant changes were recorded in SAMR1 animals. GH treatment showed beneficial effects in old SAMP8 mice inducing an increase in ATP levels and inhibiting the translocation of some NFkB subunits such as p52. Our results supported the relation of NFkB activation with enhanced apoptosis and pro-inflammatory status in old SAMP8 mice and suggested a selective beneficial effect of the GH treatment, which was able to partially reduce the incidence of some deleterious changes in the heart of those mice.

Expression Patterns of Odorant Receptors and Response Properties of Olfactory Sensory Neurons in Aged Mice

OpenAIRE

Lee, Anderson C.; Tian, Huikai; Grosmaitre, Xavier; Ma, Minghong

2009-01-01

The sense of smell deteriorates in normal aging, but the underling mechanisms are still elusive. Here we investigated age-related alterations in expression patterns of odorant receptor (OR) genes and functional properties of olfactory sensory neurons (OSNs)—2 critical factors that define the odor detection threshold in the olfactory epithelium. Using in situ hybridization for 9 representative OR genes, we compared the cell densities of each OR in coronal nose sections at different ages (3–27 ...

Types and rate of cataract development in mice irradiated at different ages

International Nuclear Information System (INIS)

Gajewski, A.K.; Majewska, K.; Slowikowska, M.G.; Chomiczewski, K.; Kulig, A.

1977-01-01

The effect of age on the development of radiation cataract has been investigated in an inbred A strain of mice and, as a result, the patterns of age dependence and senile mice cataract development were obtained. In general, the lenses of mice 1 to 3 days old were the most sensitive to radiation; the maximum resistance was noted in 5-day-old mice, and from this age up to 3 to 7 weeks of life there was a period of increasing sensitivity. In older animals the lens sensitivity tends to level off. The early stages of cataract occurred in all irradiated groups at a younger age than in the control group, but the late stages occurred in irradiated groups at the same age as the senile cataract occurred in the control group. Two types of cataract were observed. One was typical for young irradiated mice 1 to 5 days of age and the other was typical for all remaining irradiated groups and for a control group. Also, an attempt was made to correlate the obtained results with the cell kinetics in normal lens epithelium

Novel approach to select genes from RMA normalized microarray data using functional hearing tests in aging mice

Science.gov (United States)

D'Souza, Mary; Zhu, Xiaoxia; Frisina, Robert D.

2008-01-01

Presbycusis – age-related hearing loss – is the number one communicative disorder and one of the top three chronic medical condition of our aged population. High-throughput technologies potentially can be used to identify differentially expressed genes that may be better diagnostic and therapeutic targets for sensory and neural disorders. Here we analyzed gene expression for a set of GABA receptors in the cochlea of aging CBA mice using the Affymetrix GeneChip MOE430A. Functional phenotypic hearing measures were made, including auditory brainstem response (ABR) thresholds and distortion-product otoacoustic emission (DPOAE) amplitudes (four age groups). Four specific criteria were used to assess gene expression changes from RMA normalized microarray data (40 replicates). Linear regression models were used to fit the neurophysiological hearing measurements to probe-set expression profiles. These data were first subjected to one-way ANOVA, and then linear regression was performed. In addition, the log signal ratio was converted to fold change, and selected gene expression changes were confirmed by relative real-time PCR. Major findings: expression of GABA-A receptor subunit α6 was upregulated with age and hearing loss, whereas subunit α1 was repressed. In addition, GABA-A receptor associated protein like-1 and GABA-A receptor associated protein like-2 were strongly downregulated with age and hearing impairment. Lastly, gene expression measures were correlated with pathway/network relationships relevant to the inner ear using Pathway Architect, to identify key pathways consistent with the gene expression changes observed. PMID:18455804

A dual agonist of farnesoid X receptor (FXR) and the G protein-coupled receptor TGR5, INT-767, reverses age-related kidney disease in mice.

Science.gov (United States)

Wang, Xiaoxin X; Luo, Yuhuan; Wang, Dong; Adorini, Luciano; Pruzanski, Mark; Dobrinskikh, Evgenia; Levi, Moshe

2017-07-21

Even in healthy individuals, renal function gradually declines during aging. However, an observed variation in the rate of this decline has raised the possibility of slowing or delaying age-related kidney disease. One of the most successful interventional measures that slows down and delays age-related kidney disease is caloric restriction. We undertook the present studies to search for potential factors that are regulated by caloric restriction and act as caloric restriction mimetics. Based on our prior studies with the bile acid-activated nuclear hormone receptor farnesoid X receptor (FXR) and G protein-coupled membrane receptor TGR5 that demonstrated beneficial effects of FXR and TGR5 activation in the kidney, we reasoned that FXR and TGR5 could be excellent candidates. We therefore determined the effects of aging and caloric restriction on the expression of FXR and TGR5 in the kidney. We found that FXR and TGR5 expression levels are decreased in the aging kidney and that caloric restriction prevents these age-related decreases. Interestingly, in long-lived Ames dwarf mice, renal FXR and TGR5 expression levels were also increased. A 2-month treatment of 22-month-old C57BL/6J mice with the FXR-TGR5 dual agonist INT-767 induced caloric restriction-like effects and reversed age-related increases in proteinuria, podocyte injury, fibronectin accumulation, TGF-β expression, and, most notably, age-related impairments in mitochondrial biogenesis and mitochondrial function. Furthermore, in podocytes cultured in serum obtained from old mice, INT-767 prevented the increases in the proinflammatory markers TNF-α, toll-like receptor 2 (TLR2), and TLR4. In summary, our results indicate that FXR and TGR5 may play an important role in modulation of age-related kidney disease. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Gene Expression Profiles of Main Olfactory Epithelium in Adenylyl Cyclase 3 Knockout Mice

Directory of Open Access Journals (Sweden)

Zhenshan Wang

2015-11-01

Full Text Available Adenylyl Cyclase 3 (AC3 plays an important role in the olfactory sensation-signaling pathway in mice. AC3 deficiency leads to defects in olfaction. However, it is still unknown whether AC3 deficiency affects gene expression or olfactory signal transduction pathways within the main olfactory epithelium (MOE. In this study, gene microarrays were used to screen differentially expressed genes in MOE from AC3 knockout (AC3−/− and wild-type (AC3+/+ mice. The differentially expressed genes identified were subjected to bioinformatic analysis and verified by qRT-PCR. Gene expression in the MOE from AC3−/− mice was significantly altered, compared to AC3+/+ mice. Of the 41266 gene probes, 3379 had greater than 2-fold fold change in expression levels between AC3−/− and AC3+/+ mice, accounting for 8% of the total gene probes. Of these genes, 1391 were up regulated, and 1988 were down regulated, including 425 olfactory receptor genes, 99 genes that are specifically expressed in the immature olfactory neurons, 305 genes that are specifically expressed in the mature olfactory neurons, and 155 genes that are involved in epigenetic regulation. Quantitative RT-PCR verification of the differentially expressed epigenetic regulation related genes, olfactory receptors, ion transporter related genes, neuron development and differentiation related genes, lipid metabolism and membrane protein transport etc. related genes showed that P75NTR, Hinfp, Gadd45b, and Tet3 were significantly up-regulated, while Olfr370, Olfr1414, Olfr1208, Golf, Faim2, Tsg101, Mapk10, Actl6b, H2BE, ATF5, Kirrrel2, OMP, Drd2 etc. were significantly down-regulated. In summary, AC3 may play a role in proximal olfactory signaling and play a role in the regulation of differentially expressed genes in mouse MOE.

Apolipoprotein E4 Causes Age- and Sex-Dependent Impairments of Hilar GABAergic Interneurons and Learning and Memory Deficits in Mice

Science.gov (United States)

Leung, Laura; Andrews-Zwilling, Yaisa; Yoon, Seo Yeon; Jain, Sachi; Ring, Karen; Dai, Jessica; Wang, Max Mu; Tong, Leslie; Walker, David; Huang, Yadong

2012-01-01

Apolipoprotein (apo) E4 is the major genetic risk factor for Alzheimer's disease (AD). ApoE4 has sex-dependent effects, whereby the risk of developing AD is higher in apoE4-expressing females than males. However, the mechanism underlying the sex difference, in relation to apoE4, is unknown. Previous findings indicate that apoE4 causes age-dependent impairments of hilar GABAergic interneurons in female mice, leading to learning and memory deficits. Here, we investigate whether the detrimental effects of apoE4 on hilar GABAergic interneurons are sex-dependent using apoE knock-in (KI) mice across different ages. We found that in female apoE-KI mice, there was an age-dependent depletion of hilar GABAergic interneurons, whereby GAD67- or somatostatin-positive–but not NPY- or parvalbumin-positive–interneuron loss was exacerbated by apoE4. Loss of these neuronal populations was correlated with the severity of spatial learning deficits at 16 months of age in female apoE4-KI mice; however, this effect was not observed in female apoE3-KI mice. In contrast, we found an increase in the numbers of hilar GABAergic interneurons with advancing age in male apoE-KI mice, regardless of apoE genotype. Moreover, male apoE-KI mice showed a consistent ratio of hilar inhibitory GABAergic interneurons to excitatory mossy cells approximating 1.5 that is independent of apoE genotype and age, whereas female apoE-KI mice exhibited an age-dependent decrease in this ratio, which was exacerbated by apoE4. Interestingly, there are no apoE genotype effects on GABAergic interneurons in the CA1 and CA3 subregions of the hippocampus as well as the entorhinal and auditory cortexes. These findings suggest that the sex-dependent effects of apoE4 on developing AD is in part attributable to inherent sex-based differences in the numbers of hilar GABAergic interneurons, which is further modulated by apoE genotype. PMID:23300939

The Influence of Macronutrients on Splanchnic and Hepatic Lymphocytes in Aging Mice.

Science.gov (United States)

Le Couteur, David G; Tay, Szun S; Solon-Biet, Samantha; Bertolino, Patrick; McMahon, Aisling C; Cogger, Victoria C; Colakoglu, Feyza; Warren, Alessandra; Holmes, Andrew J; Pichaud, Nicolas; Horan, Martin; Correa, Carolina; Melvin, Richard G; Turner, Nigel; Ballard, J William O; Ruohonen, Kari; Raubenheimer, David; Simpson, Stephen J

2015-12-01

There is a strong association between aging, diet, and immunity. The effects of macronutrients and energy intake on splanchnic and hepatic lymphocytes were studied in 15 month old mice. The mice were ad-libitum fed 1 of 25 diets varying in the ratios and amounts of protein, carbohydrate, and fat over their lifetime. Lymphocytes in liver, spleen, Peyers patches, mesenteric lymph nodes, and inguinal lymph nodes were evaluated using flow cytometry. Low protein intake reversed aging changes in splenic CD4 and CD8 T cells, CD4:CD8 T cell ratio, memory/effector CD4 T cells and naïve CD4 T cells. A similar influence of total caloric intake in these ad-libitum fed mice was not apparent. Protein intake also influenced hepatic NK cells and B cells, while protein to carbohydrate ratio influenced hepatic NKT cells. Hepatosteatosis was associated with increased energy and fat intake and changes in hepatic Tregs, effector/memory T, and NK cells. Hepatic NK cells were also associated with body fat, glucose tolerance, and leptin levels while hepatic Tregs were associated with hydrogen peroxide production by hepatic mitochondria. Dietary macronutrients, particularly protein, influence splanchnic lymphocytes in old age, with downstream associations with mitochondrial function, liver pathology, and obesity-related phenotype. © The Author 2014. 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.

Effects of strain and age on ear wound healing and regeneration in mice

Directory of Open Access Journals (Sweden)

R.A. Costa

2009-12-01

Full Text Available Round holes in the ears of MRL mice tend to close with characteristics of regeneration believed to be absent in other mouse strains (e.g., C57BL/6. We evaluated the kinetics and the histopathology of ear wound closure in young (8 weeks old C57BL/6 and BALB/c mice. We also used middle-aged (40 weeks old C57BL/6 mice to evaluate the influence of aging on this process. A circular through-and-through hole was made in the ear, photographs were taken at different times after injury and wound area was measured with digital analysis software. The percentages of closed area measured on day 100 were: 23.57 ± 8.66% for young BALB/c mice, 56.47 ± 7.39% for young C57BL/6 mice, and 75.31 ± 23.65% for middle-aged C57BL/6 mice. Mice were sacrificed on days 1, 3, 5, 25, 44, and 100 for histological evaluation with hematoxylin and eosin, Gomori’s trichrome, periodic acid-Schiff, or picrosirius red staining. In young mice of both strains, healing included re-epithelialization, chondrogenesis, myogenesis, and collagen deposition. Young C57BL/6 and BALB/c mice differed in the organization of collagen fibers visualized using picrosirius-polarization. Sebaceous glands and hair follicles regenerated and chondrogenesis was greater in young C57BL/6 mice. In middle-aged C57BL/6 mice all aspects of regeneration were depressed. The characteristics of regeneration were present during ear wound healing in both young BALB/c and young C57BL/6 mice although they differed in intensity and pattern. Greater ear wound closure in middle-aged C57BL/6 mice was not correlated with regeneration.

Inactivation of the Rcan2 gene in mice ameliorates the age- and diet-induced obesity by causing a reduction in food intake.

Directory of Open Access Journals (Sweden)

Xiao-yang Sun

Full Text Available Obesity is a serious international health problem that increases the risk of several diet-related chronic diseases. The genetic factors predisposing to obesity are little understood. Rcan2 was originally identified as a thyroid hormone-responsive gene. In the mouse, two splicing variants that harbor distinct tissue-specific expression patterns have been identified: Rcan2-3 is expressed predominately in the brain, whereas Rcan2-1 is expressed in the brain and other tissues such as the heart and skeletal muscle. Here, we show that Rcan2 plays an important role in the development of age- and diet-induced obesity. We found that although the loss of Rcan2 function in mice slowed growth in the first few weeks after birth, it also significantly ameliorated age- and diet-induced obesity in the mice by causing a reduction in food intake rather than increased energy expenditure. Rcan2 expression was most prominent in the ventromedial, dorsomedial and paraventricular hypothalamic nuclei governing energy balance. Fasting and refeeding experiment showed that only Rcan2-3 mRNA expression is up-regulated in the hypothalamus by fasting, and loss of Rcan2 significantly attenuates the hyperphagic response to starvation. Using double-mutant (Lep(ob/ob Rcan2(-/- mice, we were also able to demonstrate that Rcan2 and leptin regulate body weight through different pathways. Our findings indicate that there may be an Rcan2-dependent mechanism which regulates food intake and promotes weight gain through a leptin-independent pathway. This study provides novel information on the control of body weight in mice and should improve our understanding of the mechanisms of obesity in humans.

Xiaochaihutang attenuates depressive/anxiety-like behaviors of social isolation-reared mice by regulating monoaminergic system, neurogenesis and BDNF expression.

Science.gov (United States)

Ma, Jie; Wang, Fang; Yang, Jingyu; Dong, Yingxu; Su, Guangyue; Zhang, Kuo; Pan, Xing; Ma, Ping; Zhou, Tingshuo; Wu, Chunfu

2017-08-17

Xiaochaihutang (XCHT), as a classical herbal formula for the treatment of "Shaoyang syndrome" has been demonstrated to exert an antidepressant effect in multiple animal models of depression as shown in our previous studies. However, the effects of XCHT on social isolation (SI)-reared mice have not been investigated. This study aims to explore the effects of XCHT on depressive/anxiety-like behaviors of SI-reared mice, and its implicated mechanisms, including alterations in the monoaminergic system, neurogenesis and neurotrophin expression. Male C57 BL/6J mice (aged 4 weeks after weaning) were reared isolatedly for 8 weeks and XCHT (0.8, 2.3, 7.0g/kg) were given by gavage once a day. Forced swimming test (FST), tail suspension test (TST), open field test (OFT), elevated-plus maze test (EPM) and intruder-induced aggression test were used to explore the effects of XCHT on depressive/anxiety-like behaviors of SI-reared mice after administration of XCHT for 6 weeks. HPLC-MS/MS was performed to quantify the levels of neurotransmitters in the hippocampus by in vivo microdialysis, while western immunoblotting was used to evaluate the action of XCHT on the synthesis, transport and degradation of monoamine neurotransmitters. Immunofluorescence was used to study the effects of XCHT on neurogenesis and neurotrophin expression, including Ki-67, DCX, BrdU and BDNF. Our results showed that administration of XCHT (0.8, 2.3 and 7.0g/kg) for 6 weeks significantly attenuated the increase in immobility time in TST and FST, improved the anxiety-like behaviors in OFT and EPM, and improved the aggressive behaviors of SI-reared mice. XCHT significantly elevated monoamine neurotransmitters levels and inhibited 5-HT turnover (5-HIAA/5-HT) in hippocampal microdialysates of SI-reared mice. In addition, we found XCHT enhanced monoamine neurotransmitter synthesis enzymes (TPH2 and TH) expressions, inhibited serotonin transporter (SERT) expression and decreased monoamine neurotransmitter

Transgenic mice for a tamoxifen-induced, conditional expression of the Cre recombinase in osteoclasts.

Directory of Open Access Journals (Sweden)

Maria Arantzazu Sanchez-Fernandez

Full Text Available BACKGROUND: Studies on osteoclasts, the bone resorbing cells, have remained limited due to the lack of transgenic mice allowing the conditional knockout of genes in osteoclasts at any time during development or adulthood. METHODOLOGY/PRINCIPAL FINDING: We report here on the generation of transgenic mice which specifically express a tamoxifen-inducible Cre recombinase in osteoclasts. These mice, generated on C57BL/6 and FVB background, express a fusion Cre recombinase-ERT2 protein whose expression is driven by the promoter of cathepsin K (CtsK, a gene highly expressed in osteoclasts. We tested the cellular specificity of Cre activity in CtsKCreERT2 strains by breeding with Rosa26LacZ reporter mice. PCR and histological analyses of the CtsKCreERT2LacZ positive adult mice and E17.5 embryos show that Cre activity is restricted largely to bone tissue. In vitro, primary osteoclasts derived from the bone marrow of CtsKCreERT2+/-LacZ+/- adult mice show a Cre-dependent β-galactosidase activity after tamoxifen stimulation. CONCLUSIONS/SIGNIFICANCE: We have generated transgenic lines that enable the tamoxifen-induced, conditional deletion of loxP-flanked genes in osteoclasts, thus circumventing embryonic and postnatal gene lethality and avoiding gene deletion in other cell types. Such CtsKCreERT2 mice provide a convenient tool to study in vivo the different facets of osteoclast function in bone physiology during different developmental stages and adulthood of mice.

Taste information derived from T1R-expressing taste cells in mice.

Science.gov (United States)

Yoshida, Ryusuke; Ninomiya, Yuzo

2016-03-01

The taste system of animals is used to detect valuable nutrients and harmful compounds in foods. In humans and mice, sweet, bitter, salty, sour and umami tastes are considered the five basic taste qualities. Sweet and umami tastes are mediated by G-protein-coupled receptors, belonging to the T1R (taste receptor type 1) family. This family consists of three members (T1R1, T1R2 and T1R3). They function as sweet or umami taste receptors by forming heterodimeric complexes, T1R1+T1R3 (umami) or T1R2+T1R3 (sweet). Receptors for each of the basic tastes are thought to be expressed exclusively in taste bud cells. Sweet (T1R2+T1R3-expressing) taste cells were thought to be segregated from umami (T1R1+T1R3-expressing) taste cells in taste buds. However, recent studies have revealed that a significant portion of taste cells in mice expressed all T1R subunits and responded to both sweet and umami compounds. This suggests that sweet and umami taste cells may not be segregated. Mice are able to discriminate between sweet and umami tastes, and both tastes contribute to behavioural preferences for sweet or umami compounds. There is growing evidence that T1R3 is also involved in behavioural avoidance of calcium tastes in mice, which implies that there may be a further population of T1R-expressing taste cells that mediate aversion to calcium taste. Therefore the simple view of detection and segregation of sweet and umami tastes by T1R-expressing taste cells, in mice, is now open to re-examination. © 2016 Authors; published by Portland Press Limited.

[The humoral immune response in mice induced by recombinant Lactococcus lactis expressing HIV-1 gag].

Science.gov (United States)

Zhao, Xiaofei; Zhang, Cairong; Liu, Xiaojuan; Ma, Zhenghai

2014-11-01

To analyze the humoral immune response induced by recombinant Lactococcus lactis expressing HIV-1 gag in mice immunized orally, intranasally, subcutaneously or in the combined way of above three. Fifty BALB/c mice were randomly divided into 5 groups, 10 mice per group. The mice were immunized consecutively three times at two week intervals with 10(9) CFU of recombinant Lactococcus lactis expressing gag through oral, intranasal, subcutaneous administration or the mix of them. The mice that were immunized orally with Lactococcus lactis containing PMG36e served as a control group. The sera of mice were collected before primary immunization and 2 weeks after each immunization to detect the gag specific IgG by ELISA. Compared with the control group, the higher titer of serum gag specific IgG was detected in the four groups immunized with recombinant Lactococcus lactis expressing gag, and it was the highest in the mixed immunization group (PLactococcus lactis expressing gag can induce humoral immune response in mice by oral, intranasal, subcutaneous injection or the mix of them, and the mixed immunization can enhance the immune effects of Lactococcus lactis vector vaccine.

Changes with age in swimming performance of X-irradiated mice

International Nuclear Information System (INIS)

Norimura, T.; Yoshikawa, I.; Okajima, S.

1980-01-01

The time required to swim 250 cm was determined once weekly for the entire life of fifteen pairs of male dd/K mice. The irradiated group was exposed to a single 224 rad of X-rays at 20 weeks of age. Median survival time (ST 50 ) for the control was 88.9 weeks and that for the irradiated group was 77.4 weeks, and both regression lines relating to death rate and age were parallel. The swimming ability of control mice began to decrease when the mice were 40 weeks of age, after which there was a gradual reduction with age at 0.00646/day. In the irradiated group, the swimming ability decreased from seven weeks after irradiation. The time of 50% reduction of swimming speed (TRS 50 ) for the control was 78.9 weeks and that for the irradiated group was 66.3 weeks, and the slopes of the regression lines relating reduction rate and age were similar. Differences between ST 50 and TRS 50 were 10 weeks in the control and 11 weeks in the irradiated group, respectively. These results indicate that there is no basic difference in the reduction in swimming ability between control and irradiated mice. The X-irradiation may simply mean that the reduction in the swimming ability is displaced to an earlier time with no alteration in the rate of reduction, and that the earlier appearance in the irradiated group is related to premature aging as induced by irradiation. (author)

Human-derived gut microbiota modulates colonic secretion in mice by regulating 5-HT3 receptor expression via acetate production.

Science.gov (United States)

Bhattarai, Yogesh; Schmidt, Bradley A; Linden, David R; Larson, Eric D; Grover, Madhusudan; Beyder, Arthur; Farrugia, Gianrico; Kashyap, Purna C

2017-07-01

Serotonin [5-hydroxytryptamine (5-HT)], an important neurotransmitter and a paracrine messenger in the gastrointestinal tract, regulates intestinal secretion by its action primarily on 5-HT 3 and 5-HT 4 receptors. Recent studies highlight the role of gut microbiota in 5-HT biosynthesis. In this study, we determine whether human-derived gut microbiota affects host secretory response to 5-HT and 5-HT receptor expression. We used proximal colonic mucosa-submucosa preparation from age-matched Swiss Webster germ-free (GF) and humanized (HM; ex-GF colonized with human gut microbiota) mice. 5-HT evoked a significantly greater increase in short-circuit current (Δ I sc ) in GF compared with HM mice. Additionally, 5-HT 3 receptor mRNA and protein expression was significantly higher in GF compared with HM mice. Ondansetron, a 5-HT 3 receptor antagonist, inhibited 5-HT-evoked Δ I sc in GF mice but not in HM mice. Furthermore, a 5-HT 3 receptor-selective agonist, 2-methyl-5-hydroxytryptamine hydrochloride, evoked a significantly higher Δ I sc in GF compared with HM mice. Immunohistochemistry in 5-HT 3A -green fluorescent protein mice localized 5-HT 3 receptor expression to enterochromaffin cells in addition to nerve fibers. The significant difference in 5-HT-evoked Δ I sc between GF and HM mice persisted in the presence of tetrodotoxin (TTX) but was lost after ondansetron application in the presence of TTX. Application of acetate (10 mM) significantly lowered 5-HT 3 receptor mRNA in GF mouse colonoids. We conclude that host secretory response to 5-HT may be modulated by gut microbiota regulation of 5-HT 3 receptor expression via acetate production. Epithelial 5-HT 3 receptor may function as a mediator of gut microbiota-driven change in intestinal secretion. NEW & NOTEWORTHY We found that gut microbiota alters serotonin (5-HT)-evoked intestinal secretion in a 5-HT 3 receptor-dependent mechanism and gut microbiota metabolite acetate alters 5-HT 3 receptor expression in

[Expression of cannabinoid receptor I during mice skin incised wound healing course].

Science.gov (United States)

Zhao, Zhen-bin; Guan, Da-wei; Liu, Wei-wei; Wang, Tao; Fan, Yan-yan; Cheng, Zi-hui; Zheng, Ji-long; Hu, Geng-yi

2010-08-01

To investigate the expression of cannabinoid receptor I (CB1R) during mice skin incised wound healing course and time-dependent changes of CB1R in wound age determination. The changes of CBIR expression in skin incised wound were detected by immunohistochemistry and Western blotting. The control group showed a low expression of CB1R detected mainly in epidermis, hair follicles, sebaceous gland and dermomuscular layer. CB1R expression was undetectable in neutrophils in the wound specimens from 6h to 12h post-injury. CB1R positive cells were mostly mononuclear cells (MNCs) and fibroblastic cells (FBCs) from 1 d to 5 d post-injury. CB1R positive cells were mostly FBCs from 7 d to 14d post-injury. The ratio of the CB1R positive cells increased gradually in the wound specimens from 6 h to 3 d post-injury, reached peak level at 5 d, and then decreased gradually from 7d to 14 d post-injury. The positive bands of CB1R were observed in all time points of the wound healing course by Western blotting. The expression peak showed at 5 d post-injury. CB1R is activated during the wound healing course. The expression of CB1R is found in mononuclear cells, which could be involved in inflammation reaction. CBIR is observed in fibroblastic cells, which could participate in the wound healing. CB1R may be a potentially useful marker for determination of wound healing age.

Expression of GAT1 in male reproductive system and its effects on reproduction in mice.

Science.gov (United States)

Zhang, JinFu; Gui, YaPing; Yuan, Tao; Bian, CuiDong; Guo, LiHe

2009-12-01

The present study was carried out to identify GABA (gamma-aminobutyric acid) transport protein I (GAT1) in male reproductive organs and to study the effect of GAT1 overexpression on the male reproductive system in GAT1 transgenic mice (TG). Expression and location of GAT1 in testes, epididymis, and sperm of wild-type (WT) mice were identified by immunohistochemistry and western-blot. Histological changes of testes, epididymis, and sperm of transgenic mice overexpressing GAT1 were detected by immunofluorenscent staining and haematoxylin and eosin (HE) staining. GAT1 expression was detected in the testes, epididymis, and sperm of non-transgenic mice. Vacuolization and deformity of spermatogenic cells were observed in the transgenic mice, but the epididymis was unremarkable. Immunofluorenscent staining showed that the number of diastrophic and decapitated sperm increased significantly in transgenic mice to 46.9% from 7.3% in nontransgenic mice. These results suggest that abnormal expression of GAT1 could result in spermiogenesis function injury, sperm paramorphia and dysgenesis.

Expression Analysis of CB2-GFP BAC Transgenic Mice.

Science.gov (United States)

Schmöle, Anne-Caroline; Lundt, Ramona; Gennequin, Benjamin; Schrage, Hanna; Beins, Eva; Krämer, Alexandra; Zimmer, Till; Limmer, Andreas; Zimmer, Andreas; Otte, David-Marian

2015-01-01

The endocannabinoid system (ECS) is a retrograde messenger system, consisting of lipid signaling molecules that bind to at least two G-protein-coupled receptors, Cannabinoid receptor 1 and 2 (CB1 and 2). As CB2 is primarily expressed on immune cells such as B cells, T cells, macrophages, dendritic cells, and microglia, it is of great interest how CB2 contributes to immune cell development and function in health and disease. Here, understanding the mechanisms of CB2 involvement in immune-cell function as well as the trafficking and regulation of CB2 expressing cells are crucial issues. Up to now, CB2 antibodies produce unclear results, especially those targeting the murine protein. Therefore, we have generated BAC transgenic GFP reporter mice (CB2-GFPTg) to trace CB2 expression in vitro and in situ. Those mice express GFP under the CB2 promoter and display GFP expression paralleling CB2 expression on the transcript level in spleen, thymus and brain tissue. Furthermore, by using fluorescence techniques we show that the major sources for GFP-CB2 expression are B cells in spleen and blood and microglia in the brain. This novel CB2-GFP transgenic reporter mouse line represents a powerful resource to study CB2 expression in different cell types. Furthermore, it could be used for analyzing CB2-mediated mobilization and trafficking of immune cells as well as studying the fate of recruited immune cells in models of acute and chronic inflammation.

Cerebellum-specific and age-dependent expression of an endogenous retrovirus with intact coding potential

Directory of Open Access Journals (Sweden)

Itoh Takayuki

2011-10-01

Full Text Available Abstract Background Endogenous retroviruses (ERVs, including murine leukemia virus (MuLV type-ERVs (MuLV-ERVs, are presumed to occupy ~10% of the mouse genome. In this study, following the identification of a full-length MuLV-ERV by in silico survey of the C57BL/6J mouse genome, its distribution in different mouse strains and expression characteristics were investigated. Results Application of a set of ERV mining protocols identified a MuLV-ERV locus with full coding potential on chromosome 8 (named ERVmch8. It appears that ERVmch8 shares the same genomic locus with a replication-incompetent MuLV-ERV, called Emv2; however, it was not confirmed due to a lack of relevant annotation and Emv2 sequence information. The ERVmch8 sequence was more prevalent in laboratory strains compared to wild-derived strains. Among 16 different tissues of ~12 week-old female C57BL/6J mice, brain homogenate was the only tissue with evident expression of ERVmch8. Further ERVmch8 expression analysis in six different brain compartments and four peripheral neuronal tissues of C57BL/6J mice revealed no significant expression except for the cerebellum in which the ERVmch8 locus' low methylation status was unique compared to the other brain compartments. The ERVmch8 locus was found to be surrounded by genes associated with neuronal development and/or inflammation. Interestingly, cerebellum-specific ERVmch8 expression was age-dependent with almost no expression at 2 weeks and a plateau at 6 weeks. Conclusions The ecotropic ERVmch8 locus on the C57BL/6J mouse genome was relatively undermethylated in the cerebellum, and its expression was cerebellum-specific and age-dependent.

Liver-specific expression of the agouti gene in transgenic mice promotes liver carcinogenesis in the absence of obesity and diabetes

Energy Technology Data Exchange (ETDEWEB)

Kuklin, Alexander [ORNL; Mynatt, Randall [ORNL; Klebig, Mitch [ORNL; Kiefer, Laura [Glaxo Wellcome, Research Triangle Park, NC; Wilkison, William O [Glaxo Wellcome, Research Triangle Park, NC; Woychik, Richard P [Jackson Laboratory, The, Bar Harbor, ME; Michaud III, Edward J [ORNL

2004-01-01

Background: The agouti protein is a paracrine factor that is normally present in the skin of many species of mammals. Agouti regulates the switch between black and yellow hair pigmentation by signalling through the melanocortin 1 receptor (Mc1r) on melanocytes. Lethal yellow (Ay) and viable yellow (Avy) are dominant regulatory mutations in the mouse agouti gene that cause the wild- ype protein to be produced at abnormally high levels throughout the body. Mice harboring these mutations exhibit a pleiotropic syndrome characterized by yellow coat color, obesity, hyperglycemia, hyperinsulinemia, and increased susceptibility to hyperplasia and carcinogenesis in numerous tissues, including the liver. The goal of this research was to determine if ectopic expression of the agouti gene in the liver alone is sufficient to recapitulate any aspect of this syndrome. For this purpose, we generated lines of transgenic mice expressing high levels of agouti in the liver under the regulatory control of the albumin promoter. Expression levels of the agouti transgene in the liver were quantified by Northern blot analysis. Functional agouti protein in the liver of transgenic mice was assayed by its ability to inhibit binding of the -melanocyte stimulating hormone ( MSH) to the Mc1r. Body weight, plasma insulin and blood glucose levels were analyzed in control and transgenic mice. Control and transgenic male mice were given a single intraperitoneal injection (10 mg/kg) of the hepatocellular carcinogen, diethylnitrosamine (DEN), at 15 days of age. Mice were euthanized at 36 or 40 weeks after DEN injection and the number of tumors per liver and total liver weights were recorded. Results: The albumin-agouti transgene was expressed at high levels in the livers of mice and produced a functional agouti protein. Albumin-agouti transgenic mice had normal body weights and normal levels of blood glucose and plasma insulin, but responded to chemical initiation of the liver with an increased number

Susceptibility to hippocampal kindling seizures is increased in aging C57 black mice

Directory of Open Access Journals (Sweden)

Kurt R. Stover

2017-12-01

Full Text Available The incidence of seizures increases with old age. Stroke, dementia and brain tumors are recognized risk factors for new-onset seizures in the aging populations and the incidence of these conditions also increased with age. Whether aging is associated with higher seizure susceptibility in the absence of the above pathologies remains unclear. We used classic kindling to explore this issue as the kindling model is highly reproducible and allows close monitoring of electrographic and motor seizure activities in individual animals. We kindled male young and aging mice (C57BL/6 strain, 2–3 and 18–22 months of age via daily hippocampal CA3 stimulation and monitored seizure activity via video and electroencephalographic recordings. The aging mice needed fewer stimuli to evoke stage-5 motor seizures and exhibited longer hippocampal afterdischarges and more frequent hippocampal spikes relative to the young mice, but afterdischarge thresholds and cumulative afterdischarge durations to stage 5 motor seizures were not different between the two age groups. While hippocampal injury and structural alterations at cellular and micro-circuitry levels remain to be examined in the kindled mice, our present observations suggest that susceptibility to hippocampal CA3 kindling seizures is increased with aging in male C57 black mice.

Early-Onset Diabetic E1-DN Mice Develop Albuminuria and Glomerular Injury Typical of Diabetic Nephropathy

Directory of Open Access Journals (Sweden)

Mervi E. Hyvönen

2015-01-01

Full Text Available The transgenic E1-DN mice express a kinase-negative epidermal growth factor receptor in their pancreatic islets and are diabetic from two weeks of age due to impaired postnatal growth of β-cell mass. Here, we characterize the development of hyperglycaemia-induced renal injury in the E1-DN mice. Homozygous mice showed increased albumin excretion rate (AER at the age of 10 weeks; the albuminuria increased over time and correlated with blood glucose. Morphometric analysis of PAS-stained histological sections and electron microscopy images revealed mesangial expansion in homozygous E1-DN mice, and glomerular sclerosis was observed in the most hyperglycaemic mice. The albuminuric homozygous mice developed also other structural changes in the glomeruli, including thickening of the glomerular basement membrane and widening of podocyte foot processes that are typical for diabetic nephropathy. Increased apoptosis of podocytes was identified as one mechanism contributing to glomerular injury. In addition, nephrin expression was reduced in the podocytes of albuminuric homozygous E1-DN mice. Tubular changes included altered epithelial cell morphology and increased proliferation. In conclusion, hyperglycaemic E1-DN mice develop albuminuria and glomerular and tubular injury typical of human diabetic nephropathy and can serve as a new model to study the mechanisms leading to the development of diabetic nephropathy.

Age-Related Alterations in the Expression of Genes and Synaptic Plasticity Associated with Nitric Oxide Signaling in the Mouse Dorsal Striatum

Directory of Open Access Journals (Sweden)

Aisa N. Chepkova

2015-01-01

Full Text Available Age-related alterations in the expression of genes and corticostriatal synaptic plasticity were studied in the dorsal striatum of mice of four age groups from young (2-3 months old to old (18–24 months of age animals. A significant decrease in transcripts encoding neuronal nitric oxide (NO synthase and receptors involved in its activation (NR1 subunit of the glutamate NMDA receptor and D1 dopamine receptor was found in the striatum of old mice using gene array and real-time RT-PCR analysis. The old striatum showed also a significantly higher number of GFAP-expressing astrocytes and an increased expression of astroglial, inflammatory, and oxidative stress markers. Field potential recordings from striatal slices revealed age-related alterations in the magnitude and dynamics of electrically induced long-term depression (LTD and significant enhancement of electrically induced long-term potentiation in the middle-aged striatum (6-7 and 12-13 months of age. Corticostriatal NO-dependent LTD induced by pharmacological activation of group I metabotropic glutamate receptors underwent significant reduction with aging and could be restored by inhibition of cGMP hydrolysis indicating that its age-related deficit is caused by an altered NO-cGMP signaling cascade. It is suggested that age-related alterations in corticostriatal synaptic plasticity may result from functional alterations in receptor-activated signaling cascades associated with increasing neuroinflammation and a prooxidant state.

Conditional Expression of Wnt4 during Chondrogenesis Leads to Dwarfism in Mice

Science.gov (United States)

Lee, Hu-Hui; Behringer, Richard R.

2007-01-01

Wnts are expressed in the forming long bones, suggesting roles in skeletogenesis. To examine the action of Wnts in skeleton formation, we developed a genetic system to conditionally express Wnt4 in chondrogenic tissues of the mouse. A mouse Wnt4 cDNA was introduced into the ubiquitously expressed Rosa26 (R26) locus by gene targeting in embryonic stem (ES) cells. The expression of Wnt4 from the R26 locus was blocked by a neomycin selection cassette flanked by loxP sites (floxneo) that was positioned between the Rosa26 promoter and the Wnt4 cDNA, creating the allele designated R26floxneoWnt4. Wnt4 expression was activated during chondrogenesis using Col2a1-Cre transgenic mice that express Cre recombinase in differentiating chondrocytes. R26floxneoWnt4; Col2a1-Cre double heterozygous mice exhibited a growth deficiency, beginning approximately 7 to 10 days after birth, that resulted in dwarfism. In addition, they also had craniofacial abnormalities, and delayed ossification of the lumbar vertebrae and pelvic bones. Histological analysis revealed a disruption in the organization of the growth plates and a delay in the onset of the primary and secondary ossification centers. Molecular studies showed that Wnt4 overexpression caused decreased proliferation and altered maturation of chondrocytes. In addition, R26floxneoWnt4; Col2a1-Cre mice had decreased expression of vascular endothelial growth factor (VEGF). These studies demonstrate that Wnt4 overexpression leads to dwarfism in mice. The data indicate that Wnt4 levels must be regulated in chondrocytes for normal growth plate development and skeletogenesis. Decreased VEGF expression suggests that defects in vascularization may contribute to the dwarf phenotype. PMID:17505543

Conditional expression of Wnt4 during chondrogenesis leads to dwarfism in mice.

Directory of Open Access Journals (Sweden)

Hu-Hui Lee

Full Text Available Wnts are expressed in the forming long bones, suggesting roles in skeletogenesis. To examine the action of Wnts in skeleton formation, we developed a genetic system to conditionally express Wnt4 in chondrogenic tissues of the mouse. A mouse Wnt4 cDNA was introduced into the ubiquitously expressed Rosa26 (R26 locus by gene targeting in embryonic stem (ES cells. The expression of Wnt4 from the R26 locus was blocked by a neomycin selection cassette flanked by loxP sites (floxneo that was positioned between the Rosa26 promoter and the Wnt4 cDNA, creating the allele designated R26(floxneoWnt4. Wnt4 expression was activated during chondrogenesis using Col2a1-Cre transgenic mice that express Cre recombinase in differentiating chondrocytes. R26(floxneoWnt4; Col2a1-Cre double heterozygous mice exhibited a growth deficiency, beginning approximately 7 to 10 days after birth, that resulted in dwarfism. In addition, they also had craniofacial abnormalities, and delayed ossification of the lumbar vertebrae and pelvic bones. Histological analysis revealed a disruption in the organization of the growth plates and a delay in the onset of the primary and secondary ossification centers. Molecular studies showed that Wnt4 overexpression caused decreased proliferation and altered maturation of chondrocytes. In addition, R26(floxneoWnt4; Col2a1-Cre mice had decreased expression of vascular endothelial growth factor (VEGF. These studies demonstrate that Wnt4 overexpression leads to dwarfism in mice. The data indicate that Wnt4 levels must be regulated in chondrocytes for normal growth plate development and skeletogenesis. Decreased VEGF expression suggests that defects in vascularization may contribute to the dwarf phenotype.

Crucial roles of Nox2-derived oxidative stress in deteriorating the function of insulin receptors and endothelium in dietary obesity of middle-aged mice.

Science.gov (United States)

Du, Junjie; Fan, Lampson M; Mai, Anna; Li, Jian-Mei

2013-11-01

Systemic oxidative stress associated with dietary calorie overload plays an important role in the deterioration of vascular function in middle-aged patients suffering from obesity and insulin resistance. However, effective therapy is still lacking. In this study, we used a mouse model of middle-aged obesity to investigate the therapeutic potential of pharmaceutical inhibition (apocynin, 5 mM supplied in the drinking water) or knockout of Nox2, an enzyme generating reactive oxygen species (ROS), in high-fat diet (HFD)-induced obesity, oxidative stress, insulin resistance and endothelial dysfunction. Littermates of C57BL/6J wild-type (WT) and Nox2 knockout (KO) mice (7 months old) were fed with a HFD (45% kcal fat) or normal chow diet (NCD, 12% kcal fat) for 16 weeks and used at 11 months of age. Compared to NCD WT mice, HFD WT mice developed obesity, insulin resistance, dyslipidaemia and hypertension. Aortic vessels from these mice showed significantly increased Nox2 expression and ROS production, accompanied by significantly increased ERK1/2 activation, reduced insulin receptor expression, decreased Akt and eNOS phosphorylation and impaired endothelium-dependent vessel relaxation to acetylcholine. All these HFD-induced abnormalities (except the hyperinsulinaemia) were absent in apocynin-treated WT or Nox2 KO mice given the same HFD. In conclusion, Nox2-derived ROS played a key role in damaging insulin receptor and endothelial function in dietary obesity after middle-age. Targeting Nox2 could represent a valuable therapeutic strategy in the metabolic syndrome. © 2013 The British Pharmacological Society.

Mitochondrial DNA mutations in mutator mice confer respiration defects and B-cell lymphoma development.

Directory of Open Access Journals (Sweden)

Takayuki Mito

Full Text Available Mitochondrial DNA (mtDNA mutator mice are proposed to express premature aging phenotypes including kyphosis and hair loss (alopecia due to their carrying a nuclear-encoded mtDNA polymerase with a defective proofreading function, which causes accelerated accumulation of random mutations in mtDNA, resulting in expression of respiration defects. On the contrary, transmitochondrial mito-miceΔ carrying mtDNA with a large-scale deletion mutation (ΔmtDNA also express respiration defects, but not express premature aging phenotypes. Here, we resolved this discrepancy by generating mtDNA mutator mice sharing the same C57BL/6J (B6J nuclear background with that of mito-miceΔ. Expression patterns of premature aging phenotypes are very close, when we compared between homozygous mtDNA mutator mice carrying a B6J nuclear background and selected mito-miceΔ only carrying predominant amounts of ΔmtDNA, in their expression of significant respiration defects, kyphosis, and a short lifespan, but not the alopecia. Therefore, the apparent discrepancy in the presence and absence of premature aging phenotypes in mtDNA mutator mice and mito-miceΔ, respectively, is partly the result of differences in the nuclear background of mtDNA mutator mice and of the broad range of ΔmtDNA proportions of mito-miceΔ used in previous studies. We also provided direct evidence that mtDNA abnormalities in homozygous mtDNA mutator mice are responsible for respiration defects by demonstrating the co-transfer of mtDNA and respiration defects from mtDNA mutator mice into mtDNA-less (ρ(0 mouse cells. Moreover, heterozygous mtDNA mutator mice had a normal lifespan, but frequently developed B-cell lymphoma, suggesting that the mtDNA abnormalities in heterozygous mutator mice are not sufficient to induce a short lifespan and aging phenotypes, but are able to contribute to the B-cell lymphoma development during their prolonged lifespan.

Spontaneous mutation of Dock7 results in lower trabecular bone mass and impaired periosteal expansion in aged female Misty mice.

Science.gov (United States)

Le, Phuong T; Bishop, Kathleen A; Maridas, David E; Motyl, Katherine J; Brooks, Daniel J; Nagano, Kenichi; Baron, Roland; Bouxsein, Mary L; Rosen, Clifford J

2017-12-01

adipocytes were elevated 3.5 fold over +/+ (p=0.014). Consistent with reduced bone formation, osteoblast gene expression of Alp, Col1a1, Runx-2, Sp7, and Bglap was significantly decreased in m/m whole bone. Furthermore, markers of osteoclasts were either unchanged or suppressed. Bone marrow stromal cell migration and motility were inhibited in culture and changes in senescence markers suggest that osteoblast function may also be inhibited with loss of Dock7 expression in m/m. Finally, increased Oil Red O staining in m/m ear mesenchymal stem cells during adipogenesis highlights a potential shift of cells from the osteogenic to adipogenic lineages. In summary, loss of Dock7 in the aging m/m resulted in an impairment of periosteal and endocortical envelope expansion, but did not alter age-related trabecular bone loss. These studies establish Dock7 as a critical regulator of both cortical and trabecular bone mass, and demonstrate for the first time a novel role of Dock7 in modulating compensatory changes in the periosteum with aging. Copyright © 2017 Elsevier Inc. All rights reserved.

Expression of p53, MDM2 in a mice hydradecarcinoma model induced by γ-ray irradiation

International Nuclear Information System (INIS)

Huang Yuecheng; Cai Jianming; Han Ling; Gao Fu; Sun Ding; Dong Zhitao; Zhe Wanli

2004-01-01

Objective: To investigate the role of the p53, MDM2 in carcinogenesis of mice hydradecarcinoma induced by γ-rays. Methods: A radiation-induced mice hydradecarcinoma model was established by γ-ray irradiation. Expression of MDM2 protein in hydradecarcinoma tissue, paracancerous tissue and normal control tissue was detected with Western blot. Immunoprecipitation (IP) was conducted to examine the phosphorylation level of MDM2 protein. PCR-SSCP was performed to detect p53 gene mutation. Results: Compared with the normal control tissue, the MDM2 protein expression and its phosphorylation level were significantly higher in hydradecarcinoma tissue. SSCP showed there were p53 gene mutations in hydradecarcinoma samples. Conclusion: p53/MDM2 pathway may be involved in the development and progression of hydradecarcinoma induced by γ-ray irradiation. The over-expression of MDM2 and hyperphosphorylation may be responsible for malignant transformation induced by irradiation by a possible mechanism of p53 inactivation. The gene mutation of p53 further supported the hypothesis that p53/MDM2 pathway played a central role in carcinogenesis of γray induced hydradecarcinoma. (authors)

Effects of prolonged irradiation by low dose-rate ionizing radiation on the gene expression of hemopoietic factors of mice

Energy Technology Data Exchange (ETDEWEB)

Shirata, Katsutoshi; Saitou, Mikio; Yanai, Takanori; Sato, Fumiaki [Institute for Environmental Science, Rokkasho, Aomori (Japan)

2000-07-01

To evaluate the effect of prolonged low-dose irradiation on the gene expression of hemopoietic factors in tissues, gene expression was analyzed in the spleen as a hemopoietic tissue that is well known to be one of the most sensitive tissues to irradiation. SPF C3H/HeN female mice (Clea Japan Inc.) were irradiated under SPF conditions with {sup 137}Cs {gamma}-rays at doses of 2, 4, 6, and 8 Gy and a dose rate of 20 mGy/day. Non-irradiated mice of the same age were maintained as controls. At the end of the period of irradiation, both groups of mice were sacrificed and dissected to extract total RNA from their tissues. Reverse transcriptase-polymerase chain reaction (RT-PCR) and the Northern hybridization were employed to detect gene expression. RT-PCT showed no marked changes in the gene expression of GM-CSF. IL-6 gene expression was shown to tend to be enhanced by prolonged low-dose irradiation. The results of Northern hybridization showed that IL-6 mRNA was expressed slightly in both groups, and it was too weak to compare the difference in mRNA expression level between the irradiated group and the controls. No mRNA expression of GM-CSF was detected by Northern hybridization. Based on these results, it was concluded that the gene expression levels of IL-6 and GM-CSF were inadequate to detect the chemiluminescence signals without amplification. It was therefore concluded that improvement of detection sensitivity and larger RNA samples would be necessary for further analysis of the gene expression of hemopoietic factors. (K.H.)

Glio-vascular changes during ageing in wild-type and Alzheimer's disease-like APP/PS1 mice.

Science.gov (United States)

Janota, C S; Brites, D; Lemere, C A; Brito, M A

2015-09-16

Vascular and glial involvement in the development of neurodegenerative disorders, such as Alzheimer's disease (AD), and age-related brain vulnerabilities have been suggested. Therefore, we sought to: (i) investigate which vascular and glial events are evident in ageing and/or AD, (ii) to establish the temporal evolution of vascular and glial changes in AD-like and wild-type (WT) mice and (iii) to relate them to amyloid-β (Aβ) peptide accumulation. We examined immunohistochemically hippocampi and cortex from APP/PS1dE9 and WT C57BL/6 mice along ageing and disease progression (young-adulthood, middle- and old-age). Ageing resulted in the increase in receptor for advanced glycation endproducts expression, as well as the entrance of thrombin and albumin in hippocampal parenchyma. In contrast, the loss of platelet-derived growth factor receptor-β (PDGFR-β) positive cells, in both regions, was only related to AD pathogenesis. Hypovascularization was affected by both ageing and AD in the hippocampus, but resulted from the interaction between both factors in the cortex. Astrogliosis was a result of AD in hippocampus and of both factors in cortex, while microgliosis was associated with fibrillar amyloid plaques in AD-like mice and with the interaction between both factors in each of the studied regions. In sum, these data show that senile plaques precede vascular and glial alterations only in hippocampus, whereas in cortex, vascular and glial alterations, namely the loss of PDGFR-β-positive cells and astrogliosis, accompanied the first senile plaques. Hence, this study points to vascular and glial events that co-exist in AD pathogenesis and age-related brain vulnerabilities. Copyright © 2015 Elsevier B.V. All rights reserved.

IGF-1 deficiency impairs neurovascular coupling in mice: implications for cerebromicrovascular aging.

Science.gov (United States)

Toth, Peter; Tarantini, Stefano; Ashpole, Nicole M; Tucsek, Zsuzsanna; Milne, Ginger L; Valcarcel-Ares, Noa M; Menyhart, Akos; Farkas, Eszter; Sonntag, William E; Csiszar, Anna; Ungvari, Zoltan

2015-12-01

Aging is associated with marked deficiency in circulating IGF-1, which has been shown to contribute to age-related cognitive decline. Impairment of moment-to-moment adjustment of cerebral blood flow (CBF) via neurovascular coupling is thought to play a critical role in the genesis of age-related cognitive impairment. To establish the link between IGF-1 deficiency and cerebromicrovascular impairment, neurovascular coupling mechanisms were studied in a novel mouse model of IGF-1 deficiency (Igf1(f/f) -TBG-Cre-AAV8) and accelerated vascular aging. We found that IGF-1-deficient mice exhibit neurovascular uncoupling and show a deficit in hippocampal-dependent spatial memory test, mimicking the aging phenotype. IGF-1 deficiency significantly impaired cerebromicrovascular endothelial function decreasing NO mediation of neurovascular coupling. IGF-1 deficiency also impaired glutamate-mediated CBF responses, likely due to dysregulation of astrocytic expression of metabotropic glutamate receptors and impairing mediation of CBF responses by eicosanoid gliotransmitters. Collectively, we demonstrate that IGF-1 deficiency promotes cerebromicrovascular dysfunction and neurovascular uncoupling mimicking the aging phenotype, which are likely to contribute to cognitive impairment. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

ADAMTS-7 Expression Increases in the Early Stage of Angiotensin II-Induced Renal Injury in Elderly Mice

Directory of Open Access Journals (Sweden)

Yan-Xiang Gao

2014-03-01

Full Text Available Background/Aims: We investigated the recently described family of proteinases, a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTs, and matrix metalloproteinases (MMPs as inflammatory mediators in inflammatory kidney damage by studying ADAMTS-1, -4, and -7 and MMP-9 expression in elderly mouse kidneys after angiotensin II (Ang II administration. Methods: Ang II (2.5 µg/kg/min or norepinephrine (8.3 µg/kg/min was subcutaneously infused in old mice. Renal injury was assessed by hematoxylin-eosin staining, 24-h albuminuria, and immunohistochemistry to evaluate inflammatory cell markers. The mRNA and protein expression of ADAMTS-1, -4, and -7 and MMP-9 were determined using real-time PCR, Western blot, and immunohistochemistry 3 days after Ang II or norepinephrine administration. Results: Elderly mice in the Ang II group developed hypertension and pathological kidney damage. The mRNA and protein levels of ADAMTS-7 in the Ang II group were 3.3 ± 1.1 (P = 0.019 and 1.6 ± 0.1 (P = 0.047 vs. 1.0 ± 0.1 and 1.0 ± 0.1 in the control group on day 3. In contrast, treatment with the hypertensive agent norepinephrine did not lead to obvious renal damage or an increase in renal ADAMTS-7 expression. Conclusions: Renal ADAMTS-7 expression was induced by Ang II in elderly mice. The overexpression of ADATMTS-7 might contribute to early inflammatory kidney damage associated with aging.

Green tea (-)-epigallocatechin-3-gallate counteracts daytime overeating induced by high-fat diet in mice.

Science.gov (United States)

Li, Hongyu; Kek, Huiling Calvina; Lim, Joy; Gelling, Richard Wayne; Han, Weiping

2016-12-01

High-fat diet (HFD) induces overeating and obesity. Green tea (-)-epigallocatechin-3-gallate (EGCG) reduces HFD-induced body weight and body fat gain mainly through increased lipid metabolism and fat oxidation. However, little is known about its effect on HFD-induced alterations in feeding behavior. Three diet groups of wildtype C57B/6j male mice at 5 months old were fed on normal chow diet, 1 week of HFD (60% of energy) and 3 months of HFD (diet-induced obesity (DIO)) prior to EGCG supplement in respective diet. EGCG had no effect on feeding behavior in normal chow diet group. Increased daytime feeding induced by HFD was selectively corrected by EGCG treatment in HFD groups, including reversed food intake, feeding frequency and meal size in HFD + EGCG group, and reduced food intake and feeding frequency in DIO + EGCG group. Moreover, EGCG treatment altered diurnally oscillating expression pattern of key appetite-regulating genes, including AGRP, POMC, and CART, and key circadian genes Clock and Bmal1 in hypothalamus of DIO mice, indicating its central effect on feeding regulation. Our study demonstrates that EGCG supplement specifically counteracts daytime overeating induced by HFD in mice, suggesting its central role in regulating feeding behavior and energy homeostasis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The effect of NMDA-NR2B receptor subunit over-expression on olfactory memory task performance in the mouse.

Science.gov (United States)

White, Theresa L; Youngentob, Steven L

2004-09-17

The N-methyl-D-aspartate (NMDA) receptor in the forebrain is thought to modulate some forms of memory formation, with the NR2B subunit being particularly relevant to this process. Relative to wild-type mice, transgenic animals in which the NR2B subunit was over-expressed demonstrate superior memory in a number of behavioral tasks, including object recognition [Nature 401 (1999) 63]. The purpose of the present study was to explore the generality of such phenomena, interpreted as the effect of increasing NR2B expression on the retention of other types of sensory-related information. To accomplish this, we focused our evaluation on the highly salient sensory modality of olfaction. In the first experiment, mice performed both a novel-object-recognition task identical to that performed by Tang et al. [Nature 401 (1999) 63] and a novel-odor-recognition task analogously constructed. Although the results of the object recognition task were consistent with the previous literature, there was no evidence of an effect of NR2B over-expression on the retention of odor recognition memory in the specific task performed. As it was possible that, unlike object recognition memory, novel odor recognition is not NMDA-receptor-dependent, a second task was designed using the social transmission of food preference paradigm. In contrast to the foregoing olfactory task, there is evidence that the latter procedure is, indeed, NMDA-dependent. The results of the second study demonstrated that transgenic mice with NR2B over-expression had a clear memory advantage in this alternative odor memory paradigm. Taken together, these results suggest the NR2B subunit is an important component in some but not all forms of olfactory memory organization. Moreover, for those functions that are NMDA-receptor-dependent, these data support the growing literature demonstrating the importance of the NR2B subunit.

Gene expression related to oxidative stress in the heart of mice after intestinal ischemia

International Nuclear Information System (INIS)

Somaio Neto, Frederico; Ikejiri, Adauto Tsutomu; Bertoletto, Paulo Roberto; Chaves, José Carlos Bertoletto; Teruya, Roberto; Fagundes, Djalma José; Taha, Murched Omar

2014-01-01

Intestinal ischemia-reperfusion is a frequent clinical event associated to injury in distant organs, especially the heart. To investigate the gene expression of oxidative stress and antioxidant defense in the heart of inbred mice subjected to intestinal ischemia and reperfusion (IR). Twelve mice (C57BL / 6) were assigned to: IR Group (GIR) with 60 minutes of superior mesenteric artery occlusion followed by 60 minutes of reperfusion; Control Group (CG) which underwent anesthesia and laparotomy without IR procedure and was observed for 120 minutes. Intestine and heart samples were processed using the RT-qPCR / Reverse transcriptase-quantitative Polymerase Chain Reaction method for the gene expression of 84 genes related to oxidative stress and oxidative defense (Student's 't' test, p < 0.05). The intestinal tissue (GIR) was noted to have an up-regulation of 65 genes (74.71%) in comparison to normal tissue (CG), and 37 genes (44.04%) were hyper-expressed (greater than three times the threshold allowed by the algorithm). Regarding the remote effects of intestinal I/R in cardiac tissue an up-regulation of 28 genes (33.33%) was seen, but only eight genes (9.52%) were hyper-expressed three times above threshold. Four (7.14%) of these eight genes were expressed in both intestinal and cardiac tissues. Cardiomyocytes with smaller and pyknotic nuclei, rich in heterochromatin with rare nucleoli, indicating cardiac distress, were observed in the GIR. Intestinal I/R caused a statistically significant over expression of 8 genes associated with oxidative stress in remote myocardial tissue

Gene expression related to oxidative stress in the heart of mice after intestinal ischemia

Science.gov (United States)

Somaio Neto, Frederico; Ikejiri, Adauto Tsutomu; Bertoletto, Paulo Roberto; Chaves, José Carlos Bertoletto; Teruya, Roberto; Fagundes, Djalma José; Taha, Murched Omar

2014-01-01

Background Intestinal ischemia-reperfusion is a frequent clinical event associated to injury in distant organs, especially the heart. Objective To investigate the gene expression of oxidative stress and antioxidant defense in the heart of inbred mice subjected to intestinal ischemia and reperfusion (IR). Methods Twelve mice (C57BL / 6) were assigned to: IR Group (GIR) with 60 minutes of superior mesenteric artery occlusion followed by 60 minutes of reperfusion; Control Group (CG) which underwent anesthesia and laparotomy without IR procedure and was observed for 120 minutes. Intestine and heart samples were processed using the RT-qPCR / Reverse transcriptase-quantitative Polymerase Chain Reaction method for the gene expression of 84 genes related to oxidative stress and oxidative defense (Student's "t" test, p < 0.05). Results The intestinal tissue (GIR) was noted to have an up-regulation of 65 genes (74.71%) in comparison to normal tissue (CG), and 37 genes (44.04%) were hyper-expressed (greater than three times the threshold allowed by the algorithm). Regarding the remote effects of intestinal I/R in cardiac tissue an up-regulation of 28 genes (33.33%) was seen, but only eight genes (9.52%) were hyper-expressed three times above threshold. Four (7.14%) of these eight genes were expressed in both intestinal and cardiac tissues. Cardiomyocytes with smaller and pyknotic nuclei, rich in heterochromatin with rare nucleoli, indicating cardiac distress, were observed in the GIR. Conclusion Intestinal I/R caused a statistically significant over expression of 8 genes associated with oxidative stress in remote myocardial tissue. PMID:24346830

Gene expression related to oxidative stress in the heart of mice after intestinal ischemia

Energy Technology Data Exchange (ETDEWEB)

Somaio Neto, Frederico; Ikejiri, Adauto Tsutomu; Bertoletto, Paulo Roberto; Chaves, José Carlos Bertoletto [Universidade Federal da Grande Dourados - UFGD, Dourados, MS (Brazil); Teruya, Roberto [Universidade Federal do Mato Grosso do Sul - UFMS, Campo Grande, MS (Brazil); Fagundes, Djalma José, E-mail: fsomaio@cardiol.br; Taha, Murched Omar [Universidade Federal de São Paulo - UNIFESP, São Paulo, SP (Brazil)

2014-02-15

Intestinal ischemia-reperfusion is a frequent clinical event associated to injury in distant organs, especially the heart. To investigate the gene expression of oxidative stress and antioxidant defense in the heart of inbred mice subjected to intestinal ischemia and reperfusion (IR). Twelve mice (C57BL / 6) were assigned to: IR Group (GIR) with 60 minutes of superior mesenteric artery occlusion followed by 60 minutes of reperfusion; Control Group (CG) which underwent anesthesia and laparotomy without IR procedure and was observed for 120 minutes. Intestine and heart samples were processed using the RT-qPCR / Reverse transcriptase-quantitative Polymerase Chain Reaction method for the gene expression of 84 genes related to oxidative stress and oxidative defense (Student's 't' test, p < 0.05). The intestinal tissue (GIR) was noted to have an up-regulation of 65 genes (74.71%) in comparison to normal tissue (CG), and 37 genes (44.04%) were hyper-expressed (greater than three times the threshold allowed by the algorithm). Regarding the remote effects of intestinal I/R in cardiac tissue an up-regulation of 28 genes (33.33%) was seen, but only eight genes (9.52%) were hyper-expressed three times above threshold. Four (7.14%) of these eight genes were expressed in both intestinal and cardiac tissues. Cardiomyocytes with smaller and pyknotic nuclei, rich in heterochromatin with rare nucleoli, indicating cardiac distress, were observed in the GIR. Intestinal I/R caused a statistically significant over expression of 8 genes associated with oxidative stress in remote myocardial tissue.

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.

Altered left ventricular performance in aging physically active mice with an ankle sprain injury.

Science.gov (United States)

Turner, Michael J; Guderian, Sophie; Wikstrom, Erik A; Huot, Joshua R; Peck, Bailey D; Arthur, Susan T; Marino, Joseph S; Hubbard-Turner, Tricia

2016-02-01

We assessed the impact of differing physical activity levels throughout the lifespan, using a musculoskeletal injury model, on the age-related changes in left ventricular (LV) parameters in active mice. Forty male mice (CBA/J) were randomly placed into one of three running wheel groups (transected CFL group, transected ATFL/CFL group, SHAM group) or a SHAM Sedentary group (SHAMSED). Before surgery and every 6 weeks after surgery, LV parameters were measured under 2.5 % isoflurane inhalation. Group effects for daily distance run was significantly greater for the SHAM and lesser for the ATLF/CFL mice (p = 0.013) with distance run decreasing with age for all mice (p age, interaction (group × age) was noted with LV posterior wall thickness-to-radius ratios (h/r) where h/r increased with age in the ATFL/CFL and SHAMSED mice while the SHAM and CFL mice exhibited decreased h/r with age (p = 0.0002). Passive filling velocity (E wave) was significantly greater in the SHAM mice and lowest for the ATFL/CFL and SHAMSED mice (p age. Active filling velocity (A wave) was not different between groups (p = 0.10). Passive-to-active filling velocity ratio (E/A ratio) was different between groups (p activity beginning at 9 months of age. Passive-to-active filling velocity ratio decreased with age (p activity throughout the lifespan improved LV structure, passive filling velocity, and E/A ratio by 6 to 9 months of age and attenuated any negative alterations throughout the second half of life. The diastolic filling differences were found to be significantly related to the amount of activity performed by 9 months and at the end of the lifespan.

Epigenetic aging signatures in mice livers are slowed by dwarfism, calorie restriction and rapamycin treatment.

Science.gov (United States)

Wang, Tina; Tsui, Brian; Kreisberg, Jason F; Robertson, Neil A; Gross, Andrew M; Yu, Michael Ku; Carter, Hannah; Brown-Borg, Holly M; Adams, Peter D; Ideker, Trey

2017-03-28

Global but predictable changes impact the DNA methylome as we age, acting as a type of molecular clock. This clock can be hastened by conditions that decrease lifespan, raising the question of whether it can also be slowed, for example, by conditions that increase lifespan. Mice are particularly appealing organisms for studies of mammalian aging; however, epigenetic clocks have thus far been formulated only in humans. We first examined whether mice and humans experience similar patterns of change in the methylome with age. We found moderate conservation of CpG sites for which methylation is altered with age, with both species showing an increase in methylome disorder during aging. Based on this analysis, we formulated an epigenetic-aging model in mice using the liver methylomes of 107 mice from 0.2 to 26.0 months old. To examine whether epigenetic aging signatures are slowed by longevity-promoting interventions, we analyzed 28 additional methylomes from mice subjected to lifespan-extending conditions, including Prop1 df/df dwarfism, calorie restriction or dietary rapamycin. We found that mice treated with these lifespan-extending interventions were significantly younger in epigenetic age than their untreated, wild-type age-matched controls. This study shows that lifespan-extending conditions can slow molecular changes associated with an epigenetic clock in mice livers.

Idh2 deficiency accelerates renal dysfunction in aged mice.

Science.gov (United States)

Lee, Su Jeong; Cha, Hanvit; Lee, Seoyoon; Kim, Hyunjin; Ku, Hyeong Jun; Kim, Sung Hwan; Park, Jung Hyun; Lee, Jin Hyup; Park, Kwon Moo; Park, Jeen-Woo

2017-11-04

The free radical or oxidative stress theory of aging postulates that senescence is due to an accumulation of cellular oxidative damage, caused largely by reactive oxygen species (ROS) that are produced as by-products of normal metabolic processes in mitochondria. The oxidative stress may arise as a result of either increased ROS production or decreased ability to detoxify ROS. The availability of the mitochondrial NADPH pool is critical for the maintenance of the mitochondrial antioxidant system. The major enzyme responsible for generating mitochondrial NADPH is mitochondrial NADP + -dependent isocitrate dehydrogenase (IDH2). Depletion of IDH2 in mice (idh2 -/- ) shortens life span and accelerates the degeneration of multiple age-sensitive traits, such as hair grayness, skin pathology, and eye pathology. Among the various internal organs tested in this study, IDH2 depletion-induced acceleration of senescence was uniquely observed in the kidney. Renal function and structure were greatly deteriorated in 24-month-old idh2 -/- mice compared with wild-type. In addition, disruption of redox status, which promotes oxidative damage and apoptosis, was more pronounced in idh2 -/- mice. These data support a significant role for increased oxidative stress as a result of compromised mitochondrial antioxidant defenses in modulating life span in mice, and thus support the oxidative stress theory of aging. Copyright © 2017 Elsevier Inc. All rights reserved.

Health screenings for women over age 65

Science.gov (United States)

Health maintenance visit - women - over age 65; Physical exam - women - over age 65; Yearly exam - women - over age 65; Checkup - women - over age 65; Women's health - over age 65; Preventive care exam - women - over ...

Health screenings for men over age 65

Science.gov (United States)

Health maintenance visit - men - over age 65; Physical exam - men - over age 65; Yearly exam - men - over age 65; Checkup - men - over age 65; Men's health - over age 65; Preventive care exam - men - over ...

Age-dependent effect of apolipoprotein E4 on functional outcome after controlled cortical impact in mice.

Science.gov (United States)

Mannix, Rebekah C; Zhang, Jimmy; Park, Juyeon; Zhang, Xuan; Bilal, Kiran; Walker, Kendall; Tanzi, Rudolph E; Tesco, Giuseppina; Whalen, Michael J

2011-01-01

The apolipoprotein E4 (APOE4) gene leads to increased brain amyloid beta (Aβ) and poor outcome in adults with traumatic brain injury (TBI); however, its role in childhood TBI is controversial. We hypothesized that the transgenic expression of human APOE4 worsens the outcome after controlled cortical impact (CCI) in adult but not immature mice. Adult and immature APOE4 mice had worse motor outcome after CCI (P<0.001 versus wild type (WT)), but the Morris water maze performance was worse only in adult APOE4 mice (P=0.028 at 2 weeks, P=0.019 at 6 months versus WT), because immature APOE4 mice had performance similar to WT for up to 1 year after injury. Brain lesion size was similar in adult APOE4 mice but was decreased (P=0.029 versus WT) in injured immature APOE4 mice. Microgliosis was similar in all groups. Soluble brain Aβ(40) was increased at 48 hours after CCI in adult and immature APOE4 mice and in adult WT (P<0.05), and was dynamically regulated during the chronic period by APOE4 in adults but not immature mice. The data suggest age-dependent effects of APOE4 on cognitive outcome after TBI, and that therapies targeting APOE4 may be more effective in adults versus children with TBI.

Expression Analysis of CB2-GFP BAC Transgenic Mice.

Directory of Open Access Journals (Sweden)

Anne-Caroline Schmöle

Full Text Available The endocannabinoid system (ECS is a retrograde messenger system, consisting of lipid signaling molecules that bind to at least two G-protein-coupled receptors, Cannabinoid receptor 1 and 2 (CB1 and 2. As CB2 is primarily expressed on immune cells such as B cells, T cells, macrophages, dendritic cells, and microglia, it is of great interest how CB2 contributes to immune cell development and function in health and disease. Here, understanding the mechanisms of CB2 involvement in immune-cell function as well as the trafficking and regulation of CB2 expressing cells are crucial issues. Up to now, CB2 antibodies produce unclear results, especially those targeting the murine protein. Therefore, we have generated BAC transgenic GFP reporter mice (CB2-GFPTg to trace CB2 expression in vitro and in situ. Those mice express GFP under the CB2 promoter and display GFP expression paralleling CB2 expression on the transcript level in spleen, thymus and brain tissue. Furthermore, by using fluorescence techniques we show that the major sources for GFP-CB2 expression are B cells in spleen and blood and microglia in the brain. This novel CB2-GFP transgenic reporter mouse line represents a powerful resource to study CB2 expression in different cell types. Furthermore, it could be used for analyzing CB2-mediated mobilization and trafficking of immune cells as well as studying the fate of recruited immune cells in models of acute and chronic inflammation.

Cell type-specific deficiency of c-kit gene expression in mutant mice of mi/mi genotype.

Science.gov (United States)

Isozaki, K.; Tsujimura, T.; Nomura, S.; Morii, E.; Koshimizu, U.; Nishimune, Y.; Kitamura, Y.

1994-01-01

The mi locus of mice encodes a novel member of the basic-helix-loop-helix-leucine zipper protein family of transcription factors (hereafter called mi factor). In addition to microphthalmus, osteopetrosis, and lack of melanocytes, mice of mi/mi genotype are deficient in mast cells. Since the c-kit receptor tyrosine kinase plays an important role in the development of mast cells, and since the c-kit expression by cultured mast cells from mi/mi mice is deficient in both mRNA and protein levels, the mast cell deficiency of mi/mi mice has been attributed at least in part to the deficient expression of c-kit. However, it remained to be examined whether the c-kit expression was also deficient in tissues of mi/mi mice. In the present study, we examined the c-kit expression by mi/mi skin mast cells using in situ hybridization and immunohistochemistry. Moreover, we examined the c-kit expression by various cells other than mast cells in tissues of mi/mi mice. We found that the c-kit expression was deficient in mast cells but not in erythroid precursors, testicular germ cells, and neurons of mi/mi mice. This suggested that the regulation of the c-kit transcription by the mi factor was dependent on cell types. Mice of mi/mi genotype appeared to be a useful model to analyze the function of transcription factors in the whole-animal level. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7524330

Tissue Specific Expression Of Sprouty1 In Mice Protects Against High Fat Diet Induced Fat Accumulation, Bone Loss, And Metabolic Dysfunction

Science.gov (United States)

Urs, Sumithra; Henderson, Terry; Le, Phuong; Rosen, Clifford J.; Liaw, Lucy

2012-01-01

We recently characterized Sprouty1 (Spry1), a growth factor signaling inhibitor as a regulator of marrow progenitor cells promoting osteoblast differentiation at the expense of adipocytes. Adipose tissue specific Spry1 expression in mice resulted in increased bone mass and reduced body fat while conditional knockout of Spry1 had the opposite effect with decreased bone and increased body fat. Because Spry1 suppresses normal fat development, we tested the hypothesis that Spry1 expression prevents high fat diet-induced obesity, bone loss, and associated lipid abnormalities and demonstrate that Spry1 has a long-term protective effect on mice fed a high caloric diet. We studied diet-induced obesity in mice with fatty acid binding promoter (aP2)-driven expression or conditional knockout of Spry1 in adipocytes. Phenotyping was performed by whole body dual-energy X-ray absorptiometry, microCT, histology and blood analysis. In conditional Spry1 null mice, high fat diet increased body fat by 40%, impaired glucose regulation, and led to liver steatosis. However, over-expression of Spry1 led to 35% lower body fat, reduced bone loss, and normal metabolic function compared to single transgenics. This protective phenotype was associated with decreased circulating insulin (70%) and leptin (54%) compared to controls on a high fat diet. Additionally, Spry1 expression decreased adipose tissue inflammation by 45%. We show that conditional Spry1 expression in adipose tissue protects against high fat diet-induced obesity and associated bone loss. PMID:22142492

Expression and function of PML-RARA in the hematopoietic progenitor cells of Ctsg-PML-RARA mice.

Directory of Open Access Journals (Sweden)

Lukas D Wartman

Full Text Available Because PML-RARA-induced acute promyelocytic leukemia (APL is a morphologically differentiated leukemia, many groups have speculated about whether its leukemic cell of origin is a committed myeloid precursor (e.g. a promyelocyte versus an hematopoietic stem/progenitor cell (HSPC. We originally targeted PML-RARA expression with CTSG regulatory elements, based on the early observation that this gene was maximally expressed in cells with promyelocyte morphology. Here, we show that both Ctsg, and PML-RARA targeted to the Ctsg locus (in Ctsg-PML-RARA mice, are expressed in the purified KLS cells of these mice (KLS = Kit(+Lin(-Sca(+, which are highly enriched for HSPCs, and this expression results in biological effects in multi-lineage competitive repopulation assays. Further, we demonstrate the transcriptional consequences of PML-RARA expression in Ctsg-PML-RARA mice in early myeloid development in other myeloid progenitor compartments [common myeloid progenitors (CMPs and granulocyte/monocyte progenitors (GMPs], which have a distinct gene expression signature compared to wild-type (WT mice. Although PML-RARA is indeed expressed at high levels in the promyelocytes of Ctsg-PML-RARA mice and alters the transcriptional signature of these cells, it does not induce their self-renewal. In sum, these results demonstrate that in the Ctsg-PML-RARA mouse model of APL, PML-RARA is expressed in and affects the function of multipotent progenitor cells. Finally, since PML/Pml is normally expressed in the HSPCs of both humans and mice, and since some human APL samples contain TCR rearrangements and express T lineage genes, we suggest that the very early hematopoietic expression of PML-RARA in this mouse model may closely mimic the physiologic expression pattern of PML-RARA in human APL patients.

Effects of Sleep Deprivation and Aging on Long-Term and Remote Memory in Mice

Science.gov (United States)

Vecsey, Christopher G.; Park, Alan J.; Khatib, Nora; Abel, Ted

2015-01-01

Sleep deprivation (SD) following hippocampus-dependent learning in young mice impairs memory when tested the following day. Here, we examined the effects of SD on remote memory in both young and aged mice. In young mice, we found that memory is still impaired 1 mo after training. SD also impaired memory in aged mice 1 d after training, but, by a…

Radiation-induced nondisjunction of oocytes of aged mice

International Nuclear Information System (INIS)

Uchida, I.A.; Freeman, C.P.V.

1977-01-01

It is stated that some human epidemiological studies suggest that there may be an association between chromosomal nondisjunction and pre-conception abdominal exposure to X-rays in women, and that this appears to increase with age. In order to test this, some experimental evidence was sought by studying second metaphase chromosomes of cultured oocytes of mice. It had previously been found that abnormal segregation was induced in young mice by exposing them to a low dose of whole body 137 Cs γ-radiation. The new studies confirmed that this radiosensitivity increases with age. The radiation dose was kept low to minimise chromosome breakage. The results indicated that abnormal segregation may be induced during first meiotic division by in vivo exposure of mouse ovaries to low radiation doses, and that this radiosensitivity appears to increase markedly with age. This supports a suggestion that the risk of producing trisomic off-spring in humans is increased with exposure of the abdomen to diagnostic X-rays, and that this increases with age. (U.K.)

Bioactive silica nanoparticles reverse age-associated bone loss in mice.

Science.gov (United States)

Weitzmann, M Neale; Ha, Shin-Woo; Vikulina, Tatyana; Roser-Page, Susanne; Lee, Jin-Kyu; Beck, George R

2015-05-01

We recently reported that in vitro, engineered 50nm spherical silica nanoparticles promote the differentiation and activity of bone building osteoblasts but suppress bone-resorbing osteoclasts. Furthermore, these nanoparticles promote bone accretion in young mice in vivo. We have now investigated the capacity of these nanoparticles to reverse bone loss in aged mice, a model of human senile osteoporosis. Aged mice received nanoparticles weekly and bone mineral density (BMD), bone structure, and bone turnover were quantified. Our data revealed a significant increase in BMD, bone volume, and biochemical markers of bone formation. Biochemical and histological examinations failed to identify any abnormalities caused by nanoparticle administration. Our studies demonstrate that silica nanoparticles effectively blunt and reverse age-associated bone loss in mice by a mechanism involving promotion of bone formation. The data suggest that osteogenic silica nanoparticles may be a safe and effective therapeutic for counteracting age-associated bone loss. Osteoporosis poses a significant problem in the society. Based on their previous in-vitro findings, the authors' group investigated the effects of spherical silica nanoparticles in reversing bone loss in a mouse model of osteoporosis. The results showed that intra-peritoneal injections of silica nanoparticles could increase bone mineral density, with little observed toxic side effects. This novel method may prove important in future therapy for combating osteoporosis. Published by Elsevier Inc.

Learning and memory in mice with neuropathic pain: impact of old age and progranulin deficiency

Directory of Open Access Journals (Sweden)

Boris eAlbuquerque

2013-11-01

Full Text Available Persistent neuropathic pain is a frequent consequence of peripheral nerve injuries, particularly in the elderly. Using the IntelliCage we studied if a sciatic nerve injury obstructed learning and memory in young and aged mice, each in wild type and progranulin deficient mice, which develop premature signs of brain aging and are more susceptible to nerve injury evoked nociceptive hypersensitivity and hence allow to assess a potential mutual aggravation of pain and old age. Both young and aged mice developed long-term nerve injury-evoked hyperalgesia and allodynia but, in both genotypes, only aged mice with neuropathic pain showed high error rates in place avoidance acquisition tasks. Once learnt however, aged mice with neuropathic pain maintained the aversive memory longer, i.e. the extinction was significantly slowed. In addition, nerve injury in progranulin deficient mice impaired the learning of spatial sequences of awarded places, particularly in aged mice, whereas easy place preference learning was not affected by nerve injury or progranulin deficiency. The sequencing task required a discrimination of clockwise and anti-clockwise sequences and spatial flexibility to re-learn a novel sequence. The loss of spatial flexibility did not occur in sham operated mice, i.e. was a consequence of nerve injury and suggests that neuropathic pain accelerates manifestations of old age and progranulin deficiency. Neuropathic pain at old age, irrespective of the genotype, resulted in a long maintenance of aversive memory suggesting a negative alliance and possibly mutual aggravation of chronic neuropathic pain and aversive memory at old age.

Involvement of oxidative stress in SAMP10 mice with age-related neurodegeneration.

Science.gov (United States)

Wang, Jun; Lei, Hongtao; Hou, Jincai; Liu, Jianxun

2015-05-01

Age-related changes in the brain tissue are reflected in many aspects. We sought to determine the morphology, Nissl bodies, behavioral appearance and oxidative stress in the brain using SAMP10 mice, a substrain of the senescence-accelerated mouse. SAMP10 mice groups divided by different ages (3, 5, 8 and 14 months) were compared with those of control groups with the above corresponding ages. Cortical thickness, Nissl bodies, behavioral appearance and oxidative stress were evaluated through image software, thionine staining, step-down test and colorimetry, respectively. The weight and cortical thickness of the brain in SAMP10 mice significantly reduced from 8 months of age. The results showed that the number of Nissl bodies decreased or Nissl bodies shrank with dark staining in histology. The same result appeared in a step-down test. As the SAMP10 mice grew older, the oxidative stress-related markers superoxide dismutase decreased and malondialdehyde increased after 8 months. Glutathione peroxidase activities showed no age-related changes. The changes of brain morphology and productions of oxidative stress in the brain tissue might contribute to the behavioral abnormality. Deceleration of age-related production of oxidative stress might be expected to be a potent strategy for anti-aging interventions.

Effect of aging and Alzheimer's disease-like pathology on brain monoamines in mice

DEFF Research Database (Denmark)

Von Linstow, C. U.; Severino, Maurizio; Metaxas, Athanasios

2017-01-01

, but these can both be age- and/or disease-related. We examined whether brain monoamine levels change as part of physiological aging and/or AD-like disease in APPSWE/PS1δE9 (APP/PS1) transgenic mice. The neocortex, hippocampus, striatum, brainstem and cerebellum of 6-, 12-, 18- and 24-month-old B6C3 wild......-type (WT) mice and of 18-month old APP/PS1 and WT mice were analysed for 5-HT, DA and NA contents by high pressure liquid chromatography (HPLC), along with neocortex from 14-month-old APP/PS1 and WT mice. While, we observed no aging effect in WT mice, we detected region-specific changes in the levels...... of all monoamines in 18-month-old transgenic compared with WT mice. This included reductions in 5-HT (-30%), DA (-47%) and NA (-32%) levels in the neocortex and increases of 5-HT in the brainstem (+18%). No changes were observed in any of the monoamines in the neocortex from 14-month-old APP/PS1 mice...

Food restriction increases long-term memory persistence in adult or aged mice.

Science.gov (United States)

Talhati, F; Patti, C L; Zanin, K A; Lopes-Silva, L B; Ceccon, L M B; Hollais, A W; Bizerra, C S; Santos, R; Tufik, S; Frussa-Filho, R

2014-04-03

Food restriction (FR) seems to be the unique experimental manipulation that leads to a remarkable increase in lifespan in rodents. Evidences have suggested that FR can enhance memory in distinct animal models mainly during aging. However, only few studies systemically evaluated the effects FR on memory formation in both adult (3-month-old) and aged (18-24-month-old) mice. Thus, the aim of the present study was to investigate the effects of acute (12h) or repeated (12h/day for 2days) FR protocols on learning and memory of adult and aged mice evaluated in the plus-maze discriminative avoidance task (PM-DAT), an animal model that concurrently (but independently) evaluates learning and memory, anxiety and locomotion. We also investigated the possible role of FR-induced stress by the corticosterone concentration in adult mice. Male mice were kept at home cage with food ad libitum (CTRL-control condition) or subjected to FR during the dark phase of the cycle for 12h/day or 12h/2days. The FR protocols were applied before training, immediately after it or before testing. Our results demonstrated that only FR for 2days enhanced memory persistence when applied before training in adults and before testing in aged mice. Conversely, FR for 2days impaired consolidation and exerted no effects on retrieval irrespective of age. These effects do not seem to be related to corticosterone concentration. Collectively, these results indicate that FR for 2days can promote promnestic effects not only in aged mice but also in adults. Copyright © 2013 Elsevier Inc. All rights reserved.

Overexpression of catalase in mice reduces age-related oxidative stress and maintains sperm production.