Intravenous infusion of H2-saline suppresses oxidative stress and elevates antioxidant potential in Thoroughbred horses after racing exercise.

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Yamazaki, Masahiko; Kusano, Kanichi; Ishibashi, Toru; Kiuchi, Masataka; Koyama, Katsuhiro

2015-10-23

Upon intensive, exhaustive exercise, exercise-induced reactive oxygen species may exceed the antioxidant defence threshold, consequently resulting in muscular damage or late-onset chronic inflammation. Recently, the therapeutic antioxidant and anti-inflammatory effects of molecular hydrogen (H2) for human rheumatoid arthritis have been demonstrated. However, it is also important to clarify the effects of administrating H2 in large animals other than humans, as H2 is thought to reach the target organ by passive diffusion upon delivery from the blood flow, indicating that the distance from the administration point to the target is critical. However, data on the effects of H2 on oxidative stress in real-life exhaustive exercise in large animals are currently lacking. We here investigated 13 Thoroughbred horses administered intravenous 2-L saline with or without 0.6-ppm H2 (placebo, N = 6; H2, N = 7) before participating in a high-intensity simulation race. Intravenous H2-saline significantly suppressed oxidative stress immediately, 3 h, and 24 h after the race, although the antioxidant capability was not affected throughout the study. The serum creatine kinase, lactate, and uric acid levels were increased in both groups. Taken together, these results indicate that intravenous H2-saline can significantly and specifically suppress oxidative stress induced after exhaustive racing in Thoroughbred horses.

Antioxidant rich grape pomace extract suppresses postprandial hyperglycemia in diabetic mice by specifically inhibiting alpha-glucosidase

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Hogan Shelly

2010-08-01

Full Text Available Abstract Background Postprandial hyperglycemia is an early defect of type 2 diabetes and one of primary anti-diabetic targets. Treatment of postprandial hyperglycemia can be achieved by inhibiting intestinal α-glucosidase, the key enzyme for oligosaccharide digestion and further glucose absorption. Grape pomace is winemaking byproduct rich in bioactive food compounds such as phenolic antioxidants. This study evaluated the anti-diabetic potential of two specific grape pomace extracts by determining their antioxidant and anti-postprandial hyperglycemic activities in vitro and in vivo. Methods The extracts of red wine grape pomace (Cabernet Franc and white wine grape pomace (Chardonnay were prepared in 80% ethanol. An extract of red apple pomace was included as a comparison. The radical scavenging activities and phenolic profiles of the pomace extracts were determined through the measurement of oxygen radical absorbance capacity, DPPH radical scavenging activity, total phenolic content and flavonoids. The inhibitory effects of the pomace extracts on yeast and rat intestinal α-glucosidases were determined. Male 6-week old C57BLKS/6NCr mice were treated with streptozocin to induce diabetes. The diabetic mice were then treated with vehicle or the grape pomace extract to determine whether the oral intake of the extract can suppress postprandial hyperglycemia through the inhibition of intestinal α-glucosidases. Results The red grape pomace extract contained significantly higher amounts of flavonoids and phenolic compounds and exerted stronger oxygen radical absorbance capacity than the red apple pomace extract. Both the grape pomace extracts but not the apple pomace extract exerted significant inhibition on intestinal α-glucosidases and the inhibition appears to be specific. In the animal study, the oral intake of the grape pomace extract (400 mg/kg body weight significantly suppressed the postprandial hyperglycemia by 35% in streptozocin

Antioxidant rich grape pomace extract suppresses postprandial hyperglycemia in diabetic mice by specifically inhibiting alpha-glucosidase.

Science.gov (United States)

Hogan, Shelly; Zhang, Lei; Li, Jianrong; Sun, Shi; Canning, Corene; Zhou, Kequan

2010-08-27

Postprandial hyperglycemia is an early defect of type 2 diabetes and one of primary anti-diabetic targets. Treatment of postprandial hyperglycemia can be achieved by inhibiting intestinal α-glucosidase, the key enzyme for oligosaccharide digestion and further glucose absorption. Grape pomace is winemaking byproduct rich in bioactive food compounds such as phenolic antioxidants. This study evaluated the anti-diabetic potential of two specific grape pomace extracts by determining their antioxidant and anti-postprandial hyperglycemic activities in vitro and in vivo. The extracts of red wine grape pomace (Cabernet Franc) and white wine grape pomace (Chardonnay) were prepared in 80% ethanol. An extract of red apple pomace was included as a comparison. The radical scavenging activities and phenolic profiles of the pomace extracts were determined through the measurement of oxygen radical absorbance capacity, DPPH radical scavenging activity, total phenolic content and flavonoids. The inhibitory effects of the pomace extracts on yeast and rat intestinal α-glucosidases were determined. Male 6-week old C57BLKS/6NCr mice were treated with streptozocin to induce diabetes. The diabetic mice were then treated with vehicle or the grape pomace extract to determine whether the oral intake of the extract can suppress postprandial hyperglycemia through the inhibition of intestinal α-glucosidases. The red grape pomace extract contained significantly higher amounts of flavonoids and phenolic compounds and exerted stronger oxygen radical absorbance capacity than the red apple pomace extract. Both the grape pomace extracts but not the apple pomace extract exerted significant inhibition on intestinal α-glucosidases and the inhibition appears to be specific. In the animal study, the oral intake of the grape pomace extract (400 mg/kg body weight) significantly suppressed the postprandial hyperglycemia by 35% in streptozocin-induced diabetic mice following starch challenge. This is the

Physiological and antioxidant responses of three leguminous ...

African Journals Online (AJOL)

STORAGESEVER

2009-11-02

Nov 2, 2009 ... 2College of Animal Science and Technology, Yangzhoug University, Yangzhoug, ... The study investigated the physiological behaviors and antioxidant responses ... into H2O2, which is further scavenged by CAT and various.

Perillyl alcohol suppresses antigen-induced immune responses in the lung

International Nuclear Information System (INIS)

Imamura, Mitsuru; Sasaki, Oh; Okunishi, Katsuhide; Nakagome, Kazuyuki; Harada, Hiroaki; Kawahata, Kimito; Tanaka, Ryoichi; Yamamoto, Kazuhiko; Dohi, Makoto

2014-01-01

Highlights: •Perillyl alcohol (POH) is an isoprenoid which inhibits the mevalonate pathway. •We examined whether POH suppresses immune responses with a mouse model of asthma. •POH treatment during sensitization suppressed Ag-induced priming of CD4 + T cells. •POH suppressed airway eosinophila and cytokine production in thoracic lymph nodes. -- Abstract: Perillyl alcohol (POH) is an isoprenoid which inhibits farnesyl transferase and geranylgeranyl transferase, key enzymes that induce conformational and functional changes in small G proteins to conduct signal production for cell proliferation. Thus, it has been tried for the treatment of cancers. However, although it affects the proliferation of immunocytes, its influence on immune responses has been examined in only a few studies. Notably, its effect on antigen-induced immune responses has not been studied. In this study, we examined whether POH suppresses Ag-induced immune responses with a mouse model of allergic airway inflammation. POH treatment of sensitized mice suppressed proliferation and cytokine production in Ag-stimulated spleen cells or CD4 + T cells. Further, sensitized mice received aerosolized OVA to induce allergic airway inflammation, and some mice received POH treatment. POH significantly suppressed indicators of allergic airway inflammation such as airway eosinophilia. Cytokine production in thoracic lymph nodes was also significantly suppressed. These results demonstrate that POH suppresses antigen-induced immune responses in the lung. Considering that it exists naturally, POH could be a novel preventive or therapeutic option for immunologic lung disorders such as asthma with minimal side effects

Perillyl alcohol suppresses antigen-induced immune responses in the lung

Energy Technology Data Exchange (ETDEWEB)

Imamura, Mitsuru; Sasaki, Oh; Okunishi, Katsuhide; Nakagome, Kazuyuki; Harada, Hiroaki; Kawahata, Kimito; Tanaka, Ryoichi; Yamamoto, Kazuhiko [Department of Allergy and Rheumatology, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Dohi, Makoto, E-mail: mdohi-tky@umin.ac.jp [Department of Allergy and Rheumatology, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Institute of Respiratory Immunology, Shibuya Clinic for Respiratory Diseases and Allergology, Tokyo (Japan)

2014-01-03

Highlights: •Perillyl alcohol (POH) is an isoprenoid which inhibits the mevalonate pathway. •We examined whether POH suppresses immune responses with a mouse model of asthma. •POH treatment during sensitization suppressed Ag-induced priming of CD4{sup +} T cells. •POH suppressed airway eosinophila and cytokine production in thoracic lymph nodes. -- Abstract: Perillyl alcohol (POH) is an isoprenoid which inhibits farnesyl transferase and geranylgeranyl transferase, key enzymes that induce conformational and functional changes in small G proteins to conduct signal production for cell proliferation. Thus, it has been tried for the treatment of cancers. However, although it affects the proliferation of immunocytes, its influence on immune responses has been examined in only a few studies. Notably, its effect on antigen-induced immune responses has not been studied. In this study, we examined whether POH suppresses Ag-induced immune responses with a mouse model of allergic airway inflammation. POH treatment of sensitized mice suppressed proliferation and cytokine production in Ag-stimulated spleen cells or CD4{sup +} T cells. Further, sensitized mice received aerosolized OVA to induce allergic airway inflammation, and some mice received POH treatment. POH significantly suppressed indicators of allergic airway inflammation such as airway eosinophilia. Cytokine production in thoracic lymph nodes was also significantly suppressed. These results demonstrate that POH suppresses antigen-induced immune responses in the lung. Considering that it exists naturally, POH could be a novel preventive or therapeutic option for immunologic lung disorders such as asthma with minimal side effects.

Measurement of the total antioxidant response using a novel automated method in subjects with nonalcoholic steatohepatitis.

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Horoz, Mehmet; Bolukbas, Cengiz; Bolukbas, Fusun F; Sabuncu, Tevfik; Aslan, Mehmet; Sarifakiogullari, Serpil; Gunaydin, Necla; Erel, Ozcan

2005-11-11

Oxidative stress, an increase in oxidants and/or a decrease in antioxidant capacity, is one of the potential biochemical mechanisms involved in the pathogenesis of nonalcoholic steatohepatitis. We aimed to investigate the total antioxidant response using a novel automated method in nonalcoholic steatohepatitis subjects. As a reciprocal measure, we also aimed to determine total peroxide level in the same plasma samples. Twenty-two subjects with biopsy proven nonalcoholic steatohepatitis and 22 healthy controls were enrolled. Total antioxidant response and total peroxide level measurements were done in all participants. The ratio percentage of total peroxide level to total antioxidant response was regarded as oxidative stress index. Total antioxidant response of subjects with nonalcoholic steatohepatitis was significantly lower than controls (p total peroxide level and mean oxidative stress index were higher (all p total peroxide level, total antioxidant response and oxidative stress index (p 0.05). Nonalcoholic steatohepatitis is associated with increased oxidant capacity, especially in the presence of liver fibrosis. The novel automated assay is a reliable and easily applicable method for total plasma antioxidant response measurement in nonalcoholic steatohepatitis.

Effects of Three Fire-Suppressant Foams on the Germination and Physiological Responses of Plants

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Song, Uhram; Mun, Saeromi; Waldman, Bruce; Lee, Eun Ju

2014-10-01

Suppressant foams used to fight forest fires may leave residual effects on surviving biota that managers need to consider prior to using them. We examined how three fire-suppressant foams (FSFs) (Forexpan S, Phos-Chek-WD881, and Silv-ex) affected seed germination and physiological responses of three plant species. Exposure to FSFs, whether in diluted concentrations or those typical in the field, reduced final germination percentages of seeds grown in petri dishes and within growth chambers. However, the FSFs did not cause total germination failure in any treatment. Inhibition of germination increased with longer exposure times, but only to diluted FSF solutions. Unlike in the laboratory experiments, none of the three FSFs affected seedling emergence when tested in field conditions. Further, we found no evidence of long-term phytotoxic effects on antioxidant enzyme activity nor chlorophyll content of the plant saplings. Therefore, although the three FSFs showed evidence of phytotoxicity to plants in laboratory tests, their actual impact on terrestrial ecosystems may be minimal. We suggest that the benefits of using these FSFs to protect plants in threatened forest ecosystems outweigh their minor risks.

Measurement of the total antioxidant response using a novel automated method in subjects with nonalcoholic steatohepatitis

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Sarifakiogullari Serpil

2005-11-01

Full Text Available Abstract Background Oxidative stress, an increase in oxidants and/or a decrease in antioxidant capacity, is one of the potential biochemical mechanisms involved in the pathogenesis of nonalcoholic steatohepatitis. We aimed to investigate the total antioxidant response using a novel automated method in nonalcoholic steatohepatitis subjects. As a reciprocal measure, we also aimed to determine total peroxide level in the same plasma samples. Methods Twenty-two subjects with biopsy proven nonalcoholic steatohepatitis and 22 healthy controls were enrolled. Total antioxidant response and total peroxide level measurements were done in all participants. The ratio percentage of total peroxide level to total antioxidant response was regarded as oxidative stress index. Results Total antioxidant response of subjects with nonalcoholic steatohepatitis was significantly lower than controls (p In subjects with nonalcoholic steatohepatitis, fibrosis score was significantly correlated with total peroxide level, total antioxidant response and oxidative stress index (p 0.05. Conclusion Nonalcoholic steatohepatitis is associated with increased oxidant capacity, especially in the presence of liver fibrosis. The novel automated assay is a reliable and easily applicable method for total plasma antioxidant response measurement in nonalcoholic steatohepatitis.

Reducing the activity and secretion of microbial antioxidants enhances the immunogenicity of BCG.

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Shanmugalakshmi Sadagopal

Full Text Available In early clinical studies, the live tuberculosis vaccine Mycobacterium bovis BCG exhibited 80% protective efficacy against pulmonary tuberculosis (TB. Although BCG still exhibits reliable protection against TB meningitis and miliary TB in early childhood it has become less reliable in protecting against pulmonary TB. During decades of in vitro cultivation BCG not only lost some genes due to deletions of regions of the chromosome but also underwent gene duplication and other mutations resulting in increased antioxidant production.To determine whether microbial antioxidants influence vaccine immunogenicity, we eliminated duplicated alleles encoding the oxidative stress sigma factor SigH in BCG Tice and reduced the activity and secretion of iron co-factored superoxide dismutase. We then used assays of gene expression and flow cytometry with intracellular cytokine staining to compare BCG-specific immune responses in mice after vaccination with BCG Tice or the modified BCG vaccine. Compared to BCG, the modified vaccine induced greater IL-12p40, RANTES, and IL-21 mRNA in the spleens of mice at three days post-immunization, more cytokine-producing CD8+ lymphocytes at the peak of the primary immune response, and more IL-2-producing CD4+ lymphocytes during the memory phase. The modified vaccine also induced stronger secondary CD4+ lymphocyte responses and greater clearance of challenge bacilli.We conclude that antioxidants produced by BCG suppress host immune responses. These findings challenge the hypothesis that the failure of extensively cultivated BCG vaccines to prevent pulmonary tuberculosis is due to over-attenuation and suggest instead a new model in which BCG evolved to produce more immunity-suppressing antioxidants. By targeting these antioxidants it may be possible to restore BCG's ability to protect against pulmonary TB.

Pyrroloquinoline-quinone suppresses liver fibrogenesis in mice.

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Dongwei Jia

Full Text Available Liver fibrosis represents the consequences of a sustained wound healing response to chronic liver injuries, and its progression toward cirrhosis is the major cause of liver-related morbidity and mortality worldwide. However, anti-fibrotic treatment remains an unconquered area for drug development. Accumulating evidence indicate that oxidative stress plays a critical role in liver fibrogenesis. In this study, we found that PQQ, a natural anti-oxidant present in a wide variety of human foods, exerted potent anti-fibrotic and ROS-scavenging activity in Balb/C mouse models of liver fibrosis. The antioxidant activity of PQQ was involved in the modulation of multiple steps during liver fibrogenesis, including chronic liver injury, hepatic inflammation, as well as activation of hepatic stellate cells and production of extracellular matrix. PQQ also suppressed the up-regulation of RACK1 in activated HSCs in vivo and in vitro. Our data suggest that PQQ suppresses oxidative stress and liver fibrogenesis in mice, and provide rationale for the clinical application of PQQ in the prevention and treatment of liver fibrosis.

Antioxidant Responses Induced by UVB Radiation in Deschampsia antarctica Desv.

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Hans Köhler

2017-05-01

Full Text Available Deschampsia antarctica Desv. is one of two vascular plants that live in the Maritime Antarctic Territory and is exposed to high levels of ultraviolet-B (UVB radiation. In this work, antioxidant physiology of D. antarctica was studied in response to UVB induced oxidative changes. Samples were collected from Antarctica and maintained in vitro culture during 2 years. Plants were sub-cultured in a hydroponic system and exposed to 21.4 kJ m-2 day-1, emulating summer Antarctic conditions. Results showed rapid and significant increases in reactive oxygen species (ROS at 3 h, which rapidly decreased. No dramatic changes were observed in photosynthetic efficiency, chlorophyll content, and level of thiobarbituric acid reactive species (MDA. The enzymatic (superoxide dismutase, SOD and total peroxidases, POD and non-enzymatic antioxidant activity (total phenolic increased significantly in response to UVB treatment. These findings suggest that tolerance of D. antarctica to UVB radiation could be attributed to its ability to activate both enzymatic and non-enzymatic antioxidant systems.

Maturation of cognitive control: delineating response inhibition and interference suppression.

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Christopher R Brydges

Full Text Available Cognitive control is integral to the ability to attend to a relevant task whilst suppressing distracting information or inhibiting prepotent responses. The current study examined the development of these two subprocesses by examining electrophysiological indices elicited during each process. Thirteen 18 year-old adults and thirteen children aged 8-11 years (mean=9.77 years completed a hybrid Go/Nogo flanker task while continuous EEG data were recorded. The N2 topography for both response inhibition and interference suppression changed with increasing age. The neural activation associated with response inhibition became increasingly frontally distributed with age, and showed decreases of both amplitude and peak latency from childhood to adulthood, possibly due to reduced cognitive demands and myelination respectively occurring during this period. Interestingly, a significant N2 effect was apparent in adults, but not observed in children during trials requiring interference suppression. This could be due to more diffuse activation in children, which would require smaller levels of activation over a larger region of the brain than is reported in adults. Overall, these results provide evidence of distinct maturational processes occurring throughout late childhood and adolescence, highlighting the separability of response inhibition and interference suppression.

Leptin Suppresses Mouse Taste Cell Responses to Sweet Compounds.

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Yoshida, Ryusuke; Noguchi, Kenshi; Shigemura, Noriatsu; Jyotaki, Masafumi; Takahashi, Ichiro; Margolskee, Robert F; Ninomiya, Yuzo

2015-11-01

Leptin is known to selectively suppress neural and behavioral responses to sweet-tasting compounds. However, the molecular basis for the effect of leptin on sweet taste is not known. Here, we report that leptin suppresses sweet taste via leptin receptors (Ob-Rb) and KATP channels expressed selectively in sweet-sensitive taste cells. Ob-Rb was more often expressed in taste cells that expressed T1R3 (a sweet receptor component) than in those that expressed glutamate-aspartate transporter (a marker for Type I taste cells) or GAD67 (a marker for Type III taste cells). Systemically administered leptin suppressed taste cell responses to sweet but not to bitter or sour compounds. This effect was blocked by a leptin antagonist and was absent in leptin receptor-deficient db/db mice and mice with diet-induced obesity. Blocking the KATP channel subunit sulfonylurea receptor 1, which was frequently coexpressed with Ob-Rb in T1R3-expressing taste cells, eliminated the effect of leptin on sweet taste. In contrast, activating the KATP channel with diazoxide mimicked the sweet-suppressing effect of leptin. These results indicate that leptin acts via Ob-Rb and KATP channels that are present in T1R3-expressing taste cells to selectively suppress their responses to sweet compounds. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Response surface optimisation of extraction of antioxidants from strawberry fruit, and lipid peroxidation inhibitory potential of the fruit extract in cooked chicken patties.

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Saha, Jayati; Debnath, Moumita; Saha, Arnab; Ghosh, Tanaya; Sarkar, Prabir K

2011-08-15

Strawberries contain high levels of antioxidants and have beneficial effects against oxidative stress-mediated diseases, such as cancer. They contain multiple phenolic compounds, which contribute to their biological properties. Hence, a study was carried out to optimise the extraction of antioxidants and evaluate the antioxidant potential of strawberry fruit extract (SE) in cooked chicken patties during refrigerated storage. The activity of SE was compared with that of butylhydroxytoluene (BHT). The effect of solvent type (MeOH and EtOH), concentration (0-70%) of EtOH in the system, temperature (30-60 °C), and time (30-150 min) on DPPH•-scavenging activity of SE was investigated. Response surface methodology was used to estimate the optimum extraction conditions for each parameter. The maximum predicted DPPH• scavenging under the optimised conditions (100% MeOH, 30 °C, 150 min) was 43% at 1 mg SE mL⁻¹. Freshly prepared chicken patties were treated with 5% and 10% SE and 2% BHT, and stored aerobically at 4 °C for 6 days. SE had no influence (P extraction of compounds from strawberry that had the scavenging activity. The study shows that the extraction of natural antioxidants from strawberry can be improved by optimising several key extraction parameters. SE also acted as an effective antioxidant and suppressed lipid peroxidation in cooked chicken patties. Copyright © 2011 Society of Chemical Industry.

Interleukin-6 Reduces β-Cell Oxidative Stress by Linking Autophagy With the Antioxidant Response.

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Marasco, Michelle R; Conteh, Abass M; Reissaus, Christopher A; Cupit V, John E; Appleman, Evan M; Mirmira, Raghavendra G; Linnemann, Amelia K

2018-05-21

Production of reactive oxygen species (ROS) is a key instigator of β-cell dysfunction in diabetes. The pleiotropic cytokine IL-6 has previously been linked to β-cell autophagy but has not been studied in the context of β-cell antioxidant response. We used a combination of animal models of diabetes and analysis of cultured human islets and rodent β-cells to study how IL-6 influences antioxidant response. We show that IL-6 couples autophagy to antioxidant response to reduce β-cell and human islet ROS. β cell-specific loss of IL-6 signaling in vivo renders mice more susceptible to oxidative damage and cell death by the selective β-cell toxins streptozotocin and alloxan. IL-6-driven ROS reduction is associated with an increase in the master antioxidant factor NRF2, which rapidly translocates to the mitochondria to decrease mitochondrial activity and stimulate mitophagy. IL-6 also initiates a robust transient drop in cellular cAMP, likely contributing to the stimulation of mitophagy for ROS mitigation. Our findings suggest that coupling autophagy to antioxidant response in the β cell leads to stress adaptation that can reduce cellular apoptosis. These findings have implications for β-cell survival under diabetogenic conditions and present novel targets for therapeutic intervention. © 2018 by the American Diabetes Association.

Virulent Type A Francisella tularensis actively suppresses cytokine responses in human monocytes

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Gillette, Devyn D.; Curry, Heather M.; Cremer, Thomas; Ravneberg, David; Fatehchand, Kavin; Shah, Prexy A.; Wewers, Mark D.; Schlesinger, Larry S.; Butchar, Jonathan P.; Tridandapani, Susheela; Gavrilin, Mikhail A.

2014-01-01

Background: Human monocyte inflammatory responses differ between virulent and attenuated Francisella infection. Results: A mixed infection model showed that the virulent F. tularensis Schu S4 can attenuate inflammatory cytokine responses to the less virulent F. novicida in human monocytes. Conclusion: F. tularensis dampens inflammatory response by an active process. Significance: This suppression may contribute to enhanced pathogenicity of F. tularensis. Francisella tularensis is a Gram-negative facultative bacterium that can cause the disease tularemia, even upon exposure to low numbers of bacteria. One critical characteristic of Francisella is its ability to dampen or subvert the host immune response. Previous work has shown that monocytes infected with highly virulent F. tularensis subsp. tularensis strain Schu S4 responded with a general pattern of quantitatively reduced pro-inflammatory signaling pathway genes and cytokine production in comparison to those infected with the less virulent related F. novicida. However, it has been unclear whether the virulent Schu S4 was merely evading or actively suppressing monocyte responses. By using mixed infection assays with F. tularensis and F. novicida, we show that F. tularensis actively suppresses monocyte pro-inflammatory responses. Additional experiments show that this suppression occurs in a dose-dependent manner and is dependent upon the viability of F. tularensis. Importantly, F. tularensis was able to suppress pro-inflammatory responses to earlier infections with F. novicida. These results lend support that F. tularensis actively dampens human monocyte responses and this likely contributes to its enhanced pathogenicity. PMID:24783062

Antioxidant responses to an acute ultra-endurance exercise: impact on DNA stability and indications for an increased need for nutritive antioxidants in the early recovery phase.

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Neubauer, Oliver; Reichhold, Stefanie; Nics, Lukas; Hoelzl, Christine; Valentini, Judit; Stadlmayr, Barbara; Knasmüller, Siegfried; Wagner, Karl-Heinz

2010-10-01

Antioxidant requirements have neither been defined for endurance nor been defined for ultra-endurance athletes. To verify whether an acute bout of ultra-endurance exercise modifies the need for nutritive antioxidants, we aimed (1) to investigate the changes of endogenous and exogenous antioxidants in response to an Ironman triathlon; (2) to particularise the relevance of antioxidant responses to the indices of oxidatively damaged blood lipids, blood cell compounds and lymphocyte DNA and (3) to examine whether potential time-points of increased susceptibility to oxidative damage are associated with alterations in the antioxidant status. Blood that was collected from forty-two well-trained male athletes 2 d pre-race, immediately post-race, and 1, 5 and 19 d later was sampled. The key findings of the present study are as follows: (1) Immediately post-race, vitamin C, α-tocopherol, and levels of the Trolox equivalent antioxidant capacity, the ferric reducing ability of plasma and the oxygen radical absorbance capacity (ORAC) assays increased significantly. Exercise-induced changes in the plasma antioxidant capacity were associated with changes in uric acid, bilirubin and vitamin C. (2) Significant inverse correlations between ORAC levels and indices of oxidatively damaged DNA immediately and 1 d post-race suggest a protective role of the acute antioxidant responses in DNA stability. (3) Significant decreases in carotenoids and γ-tocopherol 1 d post-race indicate that the antioxidant intake during the first 24 h of recovery following an acute ultra-endurance exercise requires specific attention. Furthermore, the present study illustrates the importance of a diversified and well-balanced diet to maintain a physiological antioxidant status in ultra-endurance athletes in reference to recommendations.

Resveratrol, an antioxidant, protects spinal cord injury in rats by suppressing MAPK pathway

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Song Fu

2018-02-01

Full Text Available Resveratrol, a polyphenol found in various plants, including grapes, plums and peanuts has shown various medIRInal properties, including antioxidant, protection of cardiovascular disease and cancer risk. However, the effects of resveratrol on spinal cord reperfusion injury have not been investigated. Hence, the present study was designed to evaluate the effect of resveratrol on nitric oxide synthase (iNOS/p38MAPK signaling pathway and to elucidate its regulating effect on the protection of spinal cord injury. Spinal cord ischemia–reperfusion injury (IRI was performed by the infrarenal abdominal aorta with mini aneurysm clip model. The expressions of iNOS and p38MAPK and the levels of biochemical parameters, including nitrite/nitrate, malondialdehyde (MDA, advanced oxidation products (AOPP, reduced glutathione (GSH, superoxide dismutase (SOD and catalase (CAT were measured in control and experimental groups. IRI-induced rats treated with 10 mg/kg resveratrol protected spinal cord from ischemia injury as supported by improved biological parameters measured in spinal cord tissue homogenates. The resveratrol treatment significantly decreased the levels of plasma nitrite/nitrate, iNOS mRNA and protein expressions and phosphorylation of p38MAPK in IRI-induced rats. Further, IRI-produced free radicals were reduced by resveratrol treatment by increasing enzymatic and non-enzymatic antioxidant levels such as GSH, SOD and CAT. Taken together, administration of resveratrol protects the damage caused by spinal cord ischemia with potential mechanism of suppressing the activation of iNOS/p38MAPK pathway and subsequent reduction of oxidative stress due to IRI.

Role of Oxidative Stress in the Suppression of Immune Responses in Peripheral Blood Mononuclear Cells Exposed to Combustible Tobacco Product Preparation.

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Arimilli, Subhashini; Schmidt, Eckhardt; Damratoski, Brad E; Prasad, G L

2017-10-01

Cigarette smoking is a major risk factor for several human diseases. Chronic inflammation, resulting from increased oxidative stress, has been suggested as a mechanism that contributes to the increased susceptibility of smokers to cancer and microbial infections. We have previously shown that whole-smoke conditioned medium (WS-CM) and total particulate matter (TPM) prepared from Kentucky 3R4F reference cigarettes [collectively called as combustible tobacco product preparations (TPPs)] potently suppressed agonist-stimulated cytokine secretion and target cell killing in peripheral blood mononuclear cells (PBMCs). Here we have investigated the role of oxidative stress from TPPs, which alters inflammatory responses in vitro. Particularly, we investigated the mechanisms of WS-CM-induced suppression of select cytokine secretions in Toll-like receptor (TLR) agonist-stimulated cells and target cell killing by effector cells in PBMCs. Pretreatment with N-acetyl cysteine (NAC), a precursor of reduced glutathione and an established anti-oxidant, protected against DNA damage and cytotoxicity caused by exposure to WS-CM. Similarly, secretion of tumor necrosis factor (TNF), interleukin (IL)-6, and IL-8 in response to TLR-4 stimulation was restored by pretreatment with NAC. Target cell killing, a functional measure of cytolytic cells in PBMCs, is suppressed by WS-CM. Pretreatment with NAC restored the target cell killing in WS-CM treated PBMCs. This was accompanied by higher perforin levels in the effector cell populations. Collectively, these data suggest that reducing oxidative stress caused by cigarette smoke components restores select immune responses in this ex vivo model.

A systems biology perspective on Nrf2-mediated antioxidant response

International Nuclear Information System (INIS)

Zhang Qiang; Pi Jingbo; Woods, Courtney G.; Andersen, Melvin E.

2010-01-01

Cells in vivo are constantly exposed to reactive oxygen species (ROS) generated endogenously and exogenously. To defend against the deleterious consequences of ROS, cells contain multiple antioxidant enzymes expressed in various cellular compartments to scavenge these toxic species. Under oxidative stresses, these antioxidant enzymes are upregulated to restore redox homeostasis. Such an adaptive response results from the activation of a redox-sensitive gene regulatory network mediated by nuclear factor E2-related factor 2. To more completely understand how the redox control system is designed by nature to meet homeostatic goals, we have examined the network from a systems perspective using engineering approaches. As with man-made control devices, the redox control system can be decomposed into distinct functional modules, including transducer, controller, actuator, and plant. Cells achieve specific performance objectives by utilizing nested feedback loops, feedforward control, and ultrasensitive signaling motifs, etc. Given that endogenously generated ROS are also used as signaling molecules, our analysis suggests a novel mode of action to explain oxidative stress-induced pathological conditions and diseases. Specifically, by adaptively upregulating antioxidant enzymes, oxidative stress may inadvertently attenuate ROS signals that mediate physiological processes, resulting in aberrations of cellular functions and adverse consequences. Lastly, by simultaneously considering the two competing cellular tasks-adaptive antioxidant defense and ROS signaling-we re-examine the premise that dietary antioxidant supplements is generally beneficial to human health. Our analysis highlights some possible adverse effects of these widely consumed antioxidants.

Albumin Antioxidant Response to Stress in Diabetic Nephropathy Progression

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Medina-Navarro, Rafael; Corona-Candelas, Itzia; Barajas-González, Saúl; Díaz-Flores, Margarita; Durán-Reyes, Genoveva

2014-01-01

Background A new component of the protein antioxidant capacity, designated Response Surplus (RS), was recently described. A major feature of this component is the close relationship between protein antioxidant capacity and molecular structure. Oxidative stress is associated with renal dysfunction in patients with renal failure, and plasma albumin is the target of massive oxidation in nephrotic syndrome and diabetic nephropathy. The aim of the present study was to explore the albumin redox state and the RS component of human albumin isolated from diabetic patients with progressive renal damage. Methods/Principal Findings Serum aliquots were collected and albumin isolated from 125 diabetic patients divided into 5 groups according to their estimated glomerular filtration rate (GFR). In addition to clinical and biochemical variables, the albumin redox state, including antioxidant capacity, thiol group content, and RS component, were evaluated. The albumin antioxidant capacity and thiol group content were reciprocally related to the RS component in association with GFR reduction. The GFR decline and RS component were significantly negatively correlated (R = –0.83, palbumin to stress in relation to the progression of diabetic renal disease was evaluated. The findings confirm that the albumin molecular structure is closely related to its redox state, and is a key factor in the progression of diabetes nephropathy. PMID:25187963

Acute effect of Clitoria ternatea flower beverage on glycemic response and antioxidant capacity in healthy subjects: a randomized crossover trial.

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Chusak, Charoonsri; Thilavech, Thavaree; Henry, Christiani Jeyakumar; Adisakwattana, Sirichai

2018-01-08

Clitoria ternatea L., a natural food-colorant containing anthocyanin, demonstrated antioxidant and antihyperglycemic activity. The aim of this study was to determine the effects of Clitoria ternatea flower extract (CTE) on postprandial plasma glycemia response and antioxidant status in healthy men. In a randomized, crossover study, 15 healthy men (ages 22.53 ± 0.30 years; with body mass index of 21.57 ± 0.54 kg/m 2 ) consumed five beverages: (1) 50 g sucrose in 400 mL water; (2) 1 g CTE in 400 mL of water; (3) 2 g CTE in 400 mL of water; (4) 50 g sucrose and 1 g CTE in 400 mL of water; and (5) 50 g sucrose and 2 g CTE in 400 mL of water. Incremental postprandial plasma glucose, insulin, uric acid, antioxidant capacities and lipid peroxidation were measured during 3 h of administration. After 30 min ingestion, the postprandial plasma glucose and insulin levels were suppressed when consuming sucrose plus 1 g and 2 g CTE. In addition, consumption of CTE alone did not alter plasma glucose and insulin concentration in the fasting state. The significant increase in plasma antioxidant capacity (ferric reducing ability of plasma (FRAP), oxygen radical absorbance capacity (ORAC), trolox equivalent antioxidant capacity (TEAC), and protein thiol) and the decrease in malondialdehyde (MDA) level were observed in the subjects who received 1 g and 2 g CTE. Furthermore, consumption of CTE protected sucrose-induced reduction in ORAC and TEAC and increase in plasma MDA. These findings suggest that an acute ingestion of CTE increases plasma antioxidant capacity without hypoglycemia in the fasting state. It also improves postprandial glucose, insulin and antioxidant status when consumed with sucrose. Thai Clinical Trials Registry: TCTR20170609003 . Registered 09 September 2017. 'retrospectively registered'.

Cytokine and Antioxidant Regulation in the Intestine of the Gray Mouse Lemur (Microcebus murinus During Torpor

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Shannon N. Tessier

2015-04-01

Full Text Available During food shortages, the gray mouse lemur (Microcebus murinus of Madagascar experiences daily torpor thereby reducing energy expenditures. The present study aimed to understand the impacts of torpor on the immune system and antioxidant response in the gut of these animals. This interaction may be of critical importance given the trade-off between the energetically costly immune response and the need to defend against pathogen entry during hypometabolism. The protein levels of cytokines and antioxidants were measured in the small intestine (duodenum, jejunum, and ileum and large intestine of aroused and torpid lemurs. While there was a significant decrease of some pro-inflammatory cytokines (IL-6 and TNF-α in the duodenum and jejunum during torpor as compared to aroused animals, there was no change in anti-inflammatory cytokines. We observed decreased levels of cytokines (IL-12p70 and M-CSF, and several chemokines (MCP-1 and MIP-2 but an increase in MIP-1α in the jejunum of the torpid animals. In addition, we evaluated antioxidant response by examining the protein levels of antioxidant enzymes and total antioxidant capacity provided by metabolites such as glutathione (and others. Our results indicated that levels of antioxidant enzymes did not change between torpor and aroused states, although antioxidant capacity was significantly higher in the ileum during torpor. These data suggest a suppression of the immune response, likely as an energy conservation measure, and a limited role of antioxidant defenses in supporting torpor in lemur intestine.

Variation in the suppression or enhancement of responses related to drug habits as a function of stimulus classes and competing response categories.

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Haertzen, C A; Ross, F E

1980-08-01

Male prisoners who were opiate addicts (N = 47) were given three Process Association Tests of Addiction containing stimuli which evoked responses characteristic of three levels of drug habits: beginning and ending stage of addiction, intermediate stage of addiction, and an advanced level of addiction. Each test required subjects to associate 278 word stimuli with one of five options which were randomly selected from among 20 options covering the stages of addiction, steps in drug taking, and drug effects. The purpose of the study was to determine whether responses to particular options suppressed or enhanced responses to other options. A strong interaction was found between the classes of stimuli and the response options which produced suppression or enhancement. This interaction made it possible to develop a suppression scale to measure the effect of each class of stimulus. Popular responses most frequently suppressed responses of other options. Thus, when the stimuli were clean, responses of "to be clean" and "to live a normal life," which are sensitive indicators of the beginning or ending stages of addiction , suppressed responses of other stages. The response of "to be high," a prime indicator of an intermediate habit, suppressed responses of other options when the stimuli were drug names. Responses of "to be hooked" and "to fix," which are specific indicators of a strong habit, and "to be high," which is a nonspecific indicator of a strong habit, suppressed responses of many other options. In the development of new association tests the analysis of suppression could provide a basis for selectively varying option groupings in order to increase or decrease the frequently of certain responses.

Inhibition of Rho Kinase Induces Antioxidative Molecules and Suppresses Reactive Oxidative Species in Trabecular Meshwork Cells

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Tomokazu Fujimoto

2017-01-01

Full Text Available Purpose. To investigate the effect of rho kinase inhibitors on oxidative stress in trabecular meshwork (TM cells. Methods. TM cells were isolated from the eyes of cynomolgus monkeys. Y-27632 and menadione were used to inhibit rho kinase and induce production of reactive oxygen species (ROS, respectively. The cynomolgus monkey array and 12,613 probes were used in DNA microarray analysis, and the affected genes were categorized using gene ontology analysis. The mRNA levels of the target genes were confirmed by real-time RT-PCR. Intracellular oxidative stress was detected using a fluorescent reagent sensitive to ROS. Cell viability was assessed by the WST-8 assay. Results. Gene ontology analysis revealed upregulation of genes involved in antioxidant activity, and upregulation of catalase was confirmed by real-time RT-PCR after 30 min treatment with Y-27632. Production of ROS was increased by menadione, and the effect was partly suppressed by pretreatment with Y-27632. At a lower dose of menadione, Y-27632 stimulated TM cells and significantly increased their viability following menadione treatment compared to control cells. Conclusion. Using microarray analysis, Y-27632 was shown to upregulate antioxidative genes including catalase and partially reduce ROS production and cell death by oxidative stress caused by menadione.

Virulent Type A Francisella tularensis actively suppresses cytokine responses in human monocytes

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Devyn D Gilette

2014-04-01

Full Text Available Francisella tularensis is a Gram-negative facultative bacterium that can cause the disease tularemia, even upon exposure to low numbers of bacteria. One critical characteristic of Francisella is its ability to dampen or subvert the host immune response. Previous work has shown that monocytes infected with highly virulent F. tularensis subsp. tularensis strain Schu S4 responded with a general pattern of quantitatively reduced pro-inflammatory signaling pathway genes and cytokine production in comparison to those infected with the less virulent related F. novicida. However, it has been unclear whether the virulent Schu S4 was merely evading or actively suppressing monocyte responses. By using mixed infection assays with F. tularensis and F. novicida, we show that F. tularensis actively suppresses monocyte pro-inflammatory responses. Additional experiments show that this suppression occurs in a dose-dependent manner and is dependent upon the viability of F. tularensis. Importantly, F. tularensis was able to suppress pro-inflammatory responses to earlier infections with F. novicida. These results lend support that F. tularensis actively dampens human monocyte responses and this likely contributes to its enhanced pathogenicity.

Suppressive effects of coffee on the SOS responses induced by UV and chemical mutagens

International Nuclear Information System (INIS)

Obana, Hirotaka; Nakamura, Sei-ichi; Tanaka, Ryou-ichi

1986-01-01

SOS-inducing activity of UV or chemical mutagens was strongly suppressed by instant coffee in Salmonella typhimurium TA1535/pSK1002. As decaffeinated instant coffee showed a similarly strong suppressive effect, it would seem that caffeine, a known inhibitor of SOS responses, is not responsible for the effect observed. The suppression was also shown by freshly brewed coffee extracts. However, the suppression was absent in green coffee-bean extracts. These results suggest that coffee contains some substance(s) which, apart from caffeine, suppresses SOS-inducing activity of UV or chemical mutagens and that the suppressive substance(s) are produced by roasting coffee beans. (Auth.)

Phosphatidylinositol response and proliferation of oxidative enzyme-activated human T lymphocytes: suppression by plasma lipoproteins

International Nuclear Information System (INIS)

Akeson, A.L.; Scupham, D.W.; Harmony, J.A.

1984-01-01

The phosphatidylinositol (PI) response and DNA synthesis of neuraminidase and galactose oxidase (NAGO)-stimulated human T lymphocytes are suppressed by low density lipoproteins (LDL). To understand the mechanism of lymphocyte activation more fully, the PI response and DNA synthesis and suppression of these events by LDL in NAGO-stimulated T lymphocytes were characterized. Between 30 min and 6 hr after NAGO stimulation, there was an increase of 32 Pi incorporation into PI without increased incorporation into the phosphorylated forms of PI or into other phospholipids. DNA synthesis as determined by [ 3 H]thymidine incorporation depended on the lymphocyte-accessory monocyte ratio and total cell density. Optimal stimulation of the PI response and DNA synthesis occurred at the same concentration of neuraminidase and galactose oxidase. While the PI response was only partially suppressed by LDL with optimal suppression at 10 to 20 micrograms of protein/ml, DNA synthesis was completely suppressed although at much higher LDL concentrations, greater than 100 micrograms protein/ml. As monocyte numbers are increased, LDL suppression of DNA synthesis is decreased. The ability of NAGO to stimulate the PI response and DNA synthesis in a similar way, and the suppression of both events by LDL, suggests the PI response is important for lymphocyte activation and proliferation. Stimulation of human T lymphocytes by oxidative mitogens, neuraminidase, and galactose oxidase caused increased phosphatidylinositol metabolism and increased DNA synthesis. Both responses were suppressed by low density lipoproteins

Extraction and antioxidation of polysaccharide from porphyra haitanensis using response surface method

International Nuclear Information System (INIS)

Cai, C.; Yang, Y.; Zhao, M.; Jia, R.; He, P.

2017-01-01

This paper deals with the preparation and antioxidation of polysaccharide from Porphyra haitanensis. The ratio of water to raw material, extraction temperature and extraction time were taken in sequence as independent variables in single factor test, and polysaccharide yield as response value. Using Box-Benhnken central combination experimental design principles and response surface methodology, interactions of variables and their influence on polysaccharide yield of P. haitanensis were studied and the prediction model of quadratic polynomial regression equation was inferred by simulation, in which the optimum parameters for preparing polysaccharide from P. haitanensis were 88.4°C of extraction temperature, 1.97 h of extraction time and 40:1 (ml/g) of ratio of water to raw material, and polysaccharide of 15.19 % in yield from P. haitanensis was verified after two parallel test. Furthermore, the polysaccharide of P. haitanensis showed good antioxidant capacity which could be used as potential natural antioxidant products in food additives industries. (author)

Enhanced antioxidative responses of a salt-resistant wheat cultivar ...

African Journals Online (AJOL)

Enhanced antioxidative responses of a salt-resistant wheat cultivar facilitate its adaptation to salt stress. L Chen, H Yin, J Xu, X Liu. Abstract. Wheat cultivars capable of accumulating minerals under salt stress are of considerable interest for their potential to improve crop productivity and crop quality. This study addressed the ...

Threonine modulates immune response, antioxidant status and gene expressions of antioxidant enzymes and antioxidant-immune-cytokine-related signaling molecules in juvenile blunt snout bream (Megalobrama amblycephala).

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Habte-Tsion, Habte-Michael; Ren, Mingchun; Liu, Bo; Ge, Xianping; Xie, Jun; Chen, Ruli

2016-04-01

A 9-week feeding trial was conducted to investigate the effects of graded dietary threonine (Thr) levels (0.58-2.58%) on the hematological parameters, immune response, antioxidant status and hepatopancreatic gene expression of antioxidant enzymes and antioxidant-immune-cytokine-related signaling molecules in juvenile blunt snout bream. For this purpose, 3 tanks were randomly arranged and assigned to each experimental diet. Fish were fed with their respective diet to apparent satiation 4 times daily. The results indicated that white blood cell, red blood cell and haemoglobin significantly responded to graded dietary Thr levels, while hematocrit didn't. Complement components (C3 and C4), total iron-binding capacity (TIBC), immunoglobulin M (IgM), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) increased with increasing dietary Thr levels up to 1.58-2.08% and thereafter tended to decrease. Dietary Thr regulated the gene expressions of Cu/Zn-SOD, Mn-SOD and CAT, GPx1, glutathione S-transferase mu (GST), nuclear factor erythroid 2-related factor 2 (Nrf2), heat shock protein-70 (Hsp70), tumor necrosis factor-alpha (TNF-α), apolipoprotein A-I (ApoA1), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and fructose-bisphosphate aldolase B (ALDOB); while the gene expression of peroxiredoxin II (PrxII) was not significantly modified by graded Thr levels. These genes are involved in different functions including antioxidant, immune, and defense responses, energy metabolism and protein synthesis. Therefore, this study could provide a new molecular tool for studies in fish immunonutrition and shed light on the regulatory mechanisms that dietary Thr improved the antioxidant and immune capacities of fish. Copyright © 2015 Elsevier Ltd. All rights reserved.

Induction of the immune response suppression in mice inoculated with Candida albicans.

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Valdez, J C; Mesón, D E; Sirena, A; de Petrino, S F; Eugenia, M; de Jorrat, B B; de Valdex, M G

1986-03-01

There is a controversy in respect to the immunological response (humoral or cellular) concerning the defense against Candida albicans. Candidosis would induce sub-populations of suppressor cells in the host cell-immune response. This report tries to show the effect of different doses of C. albicans (alive or heat-killed) on the expression of cell-mediated and humoral immunity. The effect upon cell immunity was determined by inoculating different lots of singeneic mice, doses of varied concentration of C. albicans and checking for delayed-type hipersensitivity (D.T.H.). D.T.H. was also controlled in syngeneic normal mice which had previously been injected with inoculated mice spleen cells. Humoral immunity was assayed by measuring the induced blastogenesis by Pokeweed Mitogen on spleen mononuclear cells with different doses of C. albicans. Results obtained show that the different doses gave origin to: Suppression of humoral and cell response (10(8) alive); Suppression of only humoral response (10(6) alive); Suppression of cell response and increase of humoral response (10(9) dead); Increase of both responses (10(8) dead).

Optimization of ultrasonic extraction of phenolic antioxidants from green tea using response surface methodology.

Science.gov (United States)

Lee, Lan-Sook; Lee, Namhyouck; Kim, Young Ho; Lee, Chang-Ho; Hong, Sang Pil; Jeon, Yeo-Won; Kim, Young-Eon

2013-10-31

Response surface methodology (RSM) has been used to optimize the extraction conditions of antioxidants with relatively low caffeine content from green tea by using ultrasonic extraction. The predicted optimal conditions for the highest antioxidant activity and minimum caffeine level were found at 19.7% ethanol, 26.4 min extraction time, and 24.0 ° C extraction temperature. In the predicted optimal conditions, the experimental values were very close to the predicted values. Moreover, the ratio of (EGCg + ECg)/EGC was identified a major factor contributing to the antioxidant activity of green tea extracts. In this study, ultrasonic extraction showed that the ethanol concentration and extraction time used for antioxidant extraction could be remarkably reduced without a decrease in antioxidant activity compared to the conventional extraction conditions.

Intracellular antioxidants dissolve man-made antioxidant nanoparticles: using redox vulnerability of nanoceria to develop a responsive drug delivery system.

Science.gov (United States)

Muhammad, Faheem; Wang, Aifei; Qi, Wenxiu; Zhang, Shixing; Zhu, Guangshan

2014-01-01

Regeneratable antioxidant property of nanoceria has widely been explored to minimize the deleterious influences of reactive oxygen species. Limited information is, however, available regarding the biological interactions and subsequent fate of nanoceria in body fluids. This study demonstrates a surprising dissolution of stable and ultrasmall (4 nm) cerium oxide nanoparticles (CeO2 NPs) in response to biologically prevalent antioxidant molecules (glutathione, vitamin C). Such a redox sensitive behavior of CeO2 NPs is subsequently exploited to design a redox responsive drug delivery system for transporting anticancer drug (camptothecin). Upon exposing the CeO2 capped and drug loaded nanoconstruct to vitamin c or glutathione, dissolution-accompanied aggregation of CeO2 nanolids unleashes the drug molecules from porous silica to achieve a significant anticancer activity. Besides stimuli responsive drug delivery, immobilization of nanoceria onto the surface of mesoporous silica also facilitates us to gain a basic insight into the biotransformation of CeO2 in physiological mediums.

Studies on the effects on growth and antioxidant responses of two marine microalgal species to uniconazole

Science.gov (United States)

Mei, Xueqiao; Zheng, Kang; Wang, Lingdong; Li, Yantuan

2014-10-01

Uniconazole, as a plant growth retardant, can enhance stress tolerance in plants, possibly because of improved antioxidation defense mechanisms with higher activities of superoxide dismutase (SOD) and peroxidase (POD) enzymes that retard lipid peroxidation and membrane deterioration. These years much attention has been focused on the responses of antioxidant system in plants to uniconazole stress, but such studies on aquatic organism are very few. Moreover, no information is available on growth and antioxidant response in marine microalgae to uniconazole. In this paper, the growth and antioxidant responses of two marine microalgal species, Platymonas helgolandica and Pavlova viridis, at six uniconazole concentrations (0-15 mg L-1) were investigated. The results demonstrated that 3 mg L-1 uniconazole could increase significantly chlorophyll a and carbohydrate contents of P. helgolandica ( P enzymes, superoxide dismutase (SOD) and catalase (CAT) were enhanced remarkably at low concentrations of uniconazole. However, significant reduction of SOD and CAT activities was observed at higher concentrations of uniconazole.

Sublethal toxicity of quinalphos on oxidative stress and antioxidant responses in a freshwater fish Cyprinus carpio.

Science.gov (United States)

Hemalatha, Devan; Amala, Antony; Rangasamy, Basuvannan; Nataraj, Bojan; Ramesh, Mathan

2016-11-01

Extensive use of quinalphos, an organophosphorus pesticide, is likely to reach the aquatic environment and thereby posing a health concern for aquatic organisms. Oxidative stress and antioxidant responses may be good indicators of pesticide contamination in aquatic organisms. The data on quinalphos induced oxidative stress and antioxidant responses in carps are scanty. This study is aimed to assess the two sublethal concentrations of quinalphos (1.09 and 2.18 μL L -1 ) on oxidative stress and antioxidant responses of Cyprinus carpio for a period of 20 days. In liver, the malondialdehyde level was found to be significantly increased in both the concentrations. The results of the antioxidant parameters obtained show a significant increase in superoxide dismutase, catalase, and glutathione-S-transferase activity in liver of fish. These results demonstrate that environmentally relevant levels of the insecticide quinalphos can cause oxidative damage and increase the antioxidant scavenging capacity in C. carpio. This may reflect the potential role of these parameters as useful biomarkers for the assessment of pesticide contamination. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1399-1406, 2016. © 2015 Wiley Periodicals, Inc.

Optimization of Ultrasonic Extraction of Phenolic Antioxidants from Green Tea Using Response Surface Methodology

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Lan-Sook Lee

2013-10-01

Full Text Available Response surface methodology (RSM has been used to optimize the extraction conditions of antioxidants with relatively low caffeine content from green tea by using ultrasonic extraction. The predicted optimal conditions for the highest antioxidant activity and minimum caffeine level were found at 19.7% ethanol, 26.4 min extraction time, and 24.0 °C extraction temperature. In the predicted optimal conditions, the experimental values were very close to the predicted values. Moreover, the ratio of (EGCg + ECg/EGC was identified a major factor contributing to the antioxidant activity of green tea extracts. In this study, ultrasonic extraction showed that the ethanol concentration and extraction time used for antioxidant extraction could be remarkably reduced without a decrease in antioxidant activity compared to the conventional extraction conditions.

Carvedilol suppresses circulating and hepatic IL-6 responsible for hepatocarcinogenesis of chronically damaged liver in rats

International Nuclear Information System (INIS)

Balaha, Mohamed; Kandeel, Samah; Barakat, Waleed

2016-01-01

Carvedilol is an anti-oxidant non-selective β-blocker used for reduction of portal blood pressure, prophylaxis of esophageal varices development and bleeding in chronic liver diseases. Recently, it exhibited potent anti-inflammatory, anti-fibrotic, anti-proliferative and anti-carcinogenic effects. In the present study, we evaluated the possible suppressive effect of carvedilol on circulating and hepatic IL-6 levels responsible for hepatocarcinogenesis in a rat model of hepatic cirrhosis. Besides, its effect on hepatic STAT-3 levels, function tests, oxidative stress markers, and hydroxyproline content, hepatic tissue histopathological changes and immunohistochemical expression of E & N-cadherin. Nine-week-old male Wistar rats injected intraperitoneal by 1 ml/kg 10% CCL 4 in olive oil three times/week (every other day) for 12 weeks to induce hepatic cirrhosis. Carvedilol (10 mg/kg/day suspended in 0.5% CMC orally), silymarin (50 mg/kg/day suspended in 0.5% CMC orally) or combination of both used to treat hepatic cirrhosis from 15th to 84th day. Our data showed that carvedilol and silymarin co-treatment each alone or in combination efficiently reduced the elevated serum IL-6, ALT, AST, ALP and BIL, hepatic IL-6, STAT-3, MDA levels and hydroxyproline content. In addition, it elevated the reduced serum ALB level, hepatic CAT activity and GSH level. Meanwhile, it apparently restored the normal hepatic architecture, collagen distribution and immunohistochemical E & N-cadherin expression. Furthermore, carvedilol was superior to silymarin in improving MDA level. Moreover, the combination of carvedilol and silymarin showed an upper hand in amelioration of the CCL 4 induced hepatotoxicity than each alone. Therefore, carvedilol could be promising in prevention of hepatocarcinogenesis in chronic hepatic injuries. - Highlights: • Chronic liver damage ends into hepatocellular carcinoma in 5% of patients. • Persistent elevation of IL-6 induces hepatocarcinogenesis in chronic

Carvedilol suppresses circulating and hepatic IL-6 responsible for hepatocarcinogenesis of chronically damaged liver in rats

Energy Technology Data Exchange (ETDEWEB)

Balaha, Mohamed, E-mail: Mohamed.Balaha@Med.Tanta.Edu.Eg [Pharmacology Department, Faculty of Medicine, Tanta University, El-Gish Street, Postal No. 31527 Tanta (Egypt); Kandeel, Samah [Histology Department, Faculty of Medicine, Tanta University, El-Gish Street, Postal No. 31527 Tanta (Egypt); Barakat, Waleed [Pharmacology Department, Faculty of Medicine, Tanta University, El-Gish Street, Postal No. 31527 Tanta (Egypt)

2016-11-15

Carvedilol is an anti-oxidant non-selective β-blocker used for reduction of portal blood pressure, prophylaxis of esophageal varices development and bleeding in chronic liver diseases. Recently, it exhibited potent anti-inflammatory, anti-fibrotic, anti-proliferative and anti-carcinogenic effects. In the present study, we evaluated the possible suppressive effect of carvedilol on circulating and hepatic IL-6 levels responsible for hepatocarcinogenesis in a rat model of hepatic cirrhosis. Besides, its effect on hepatic STAT-3 levels, function tests, oxidative stress markers, and hydroxyproline content, hepatic tissue histopathological changes and immunohistochemical expression of E & N-cadherin. Nine-week-old male Wistar rats injected intraperitoneal by 1 ml/kg 10% CCL{sub 4} in olive oil three times/week (every other day) for 12 weeks to induce hepatic cirrhosis. Carvedilol (10 mg/kg/day suspended in 0.5% CMC orally), silymarin (50 mg/kg/day suspended in 0.5% CMC orally) or combination of both used to treat hepatic cirrhosis from 15th to 84th day. Our data showed that carvedilol and silymarin co-treatment each alone or in combination efficiently reduced the elevated serum IL-6, ALT, AST, ALP and BIL, hepatic IL-6, STAT-3, MDA levels and hydroxyproline content. In addition, it elevated the reduced serum ALB level, hepatic CAT activity and GSH level. Meanwhile, it apparently restored the normal hepatic architecture, collagen distribution and immunohistochemical E & N-cadherin expression. Furthermore, carvedilol was superior to silymarin in improving MDA level. Moreover, the combination of carvedilol and silymarin showed an upper hand in amelioration of the CCL{sub 4} induced hepatotoxicity than each alone. Therefore, carvedilol could be promising in prevention of hepatocarcinogenesis in chronic hepatic injuries. - Highlights: • Chronic liver damage ends into hepatocellular carcinoma in 5% of patients. • Persistent elevation of IL-6 induces hepatocarcinogenesis

Alpha-Fetoprotein, Identified as a Novel Marker for the Antioxidant Effect of Placental Extract, Exhibits Synergistic Antioxidant Activity in the Presence of Estradiol

Science.gov (United States)

Choi, Hye Yeon; Kim, Seung Woo; Kim, BongWoo; Lee, Hae Na; Kim, Su-Jeong; Song, Minjung; Kim, Sol; Kim, Jungho; Kim, Young Bong; Kim, Jin-Hoi; Cho, Ssang-Goo

2014-01-01

Placenta, as a reservoir of nutrients, has been widely used in medical and cosmetic materials. Here, we focused on the antioxidant properties of placental extract and attempted to isolate and identify the main antioxidant factors. Porcine placental extracts were prepared through homogenization or acid hydrolysis, and their antioxidant activity was investigated in the human keratinocyte HaCaT cell line. Treatment with homogenized placental extract (H-PE) increased the cell viability of H2O2-treated HaCaT cells more than two-fold. H-PE treatment suppressed H2O2-induced apoptotic and necrotic cell death and decreased intracellular ROS levels in H2O2-treated HaCaT cells. The antioxidant factors in H-PE were found to be thermo-unstable and were thus expected to include proteins. The candidate antioxidant proteins were fractionated with cation-exchange, anion-exchange, and size-exclusion chromatography, and the antioxidant properties of the chromatographic fractions were investigated. We obtained specific antioxidant fractions that suppressed ROS generation and ROS-induced DNA strand breaks. From silver staining and MALDI-TOF analyses, alpha-fetoprotein (AFP) precursor was identified as a main marker for the antioxidant effect of H-PE. Purified AFP or ectopically expressed AFP exhibited synergistic antioxidant activity in the presence of estradiol. Taken together, our data suggest that AFP, a serum glycoprotein produced at high levels during fetal development, is a novel marker protein for the antioxidant effect of the placenta that exhibits synergistic antioxidant activity in the presence of estradiol. PMID:24922551

Alpha-fetoprotein, identified as a novel marker for the antioxidant effect of placental extract, exhibits synergistic antioxidant activity in the presence of estradiol.

Directory of Open Access Journals (Sweden)

Hye Yeon Choi

Full Text Available Placenta, as a reservoir of nutrients, has been widely used in medical and cosmetic materials. Here, we focused on the antioxidant properties of placental extract and attempted to isolate and identify the main antioxidant factors. Porcine placental extracts were prepared through homogenization or acid hydrolysis, and their antioxidant activity was investigated in the human keratinocyte HaCaT cell line. Treatment with homogenized placental extract (H-PE increased the cell viability of H2O2-treated HaCaT cells more than two-fold. H-PE treatment suppressed H2O2-induced apoptotic and necrotic cell death and decreased intracellular ROS levels in H2O2-treated HaCaT cells. The antioxidant factors in H-PE were found to be thermo-unstable and were thus expected to include proteins. The candidate antioxidant proteins were fractionated with cation-exchange, anion-exchange, and size-exclusion chromatography, and the antioxidant properties of the chromatographic fractions were investigated. We obtained specific antioxidant fractions that suppressed ROS generation and ROS-induced DNA strand breaks. From silver staining and MALDI-TOF analyses, alpha-fetoprotein (AFP precursor was identified as a main marker for the antioxidant effect of H-PE. Purified AFP or ectopically expressed AFP exhibited synergistic antioxidant activity in the presence of estradiol. Taken together, our data suggest that AFP, a serum glycoprotein produced at high levels during fetal development, is a novel marker protein for the antioxidant effect of the placenta that exhibits synergistic antioxidant activity in the presence of estradiol.

Effectors from Wheat Rust Fungi Suppress Multiple Plant Defense Responses.

Science.gov (United States)

Ramachandran, Sowmya R; Yin, Chuntao; Kud, Joanna; Tanaka, Kiwamu; Mahoney, Aaron K; Xiao, Fangming; Hulbert, Scot H

2017-01-01

Fungi that cause cereal rust diseases (genus Puccinia) are important pathogens of wheat globally. Upon infection, the fungus secretes a number of effector proteins. Although a large repository of putative effectors has been predicted using bioinformatic pipelines, the lack of available high-throughput effector screening systems has limited functional studies on these proteins. In this study, we mined the available transcriptomes of Puccinia graminis and P. striiformis to look for potential effectors that suppress host hypersensitive response (HR). Twenty small (wheat, confirming its activity in a homologous system. Overall, this study provides the first evidence for the presence of effectors in Puccinia species suppressing multiple plant defense responses.

Measurement of the total antioxidant response in preeclampsia with a novel automated method.

Science.gov (United States)

Harma, Mehmet; Harma, Muge; Erel, Ozcan

2005-01-10

Preeclampsia is one of the most serious complications of pregnancy. Free radical damage has been implicated in the pathophysiology of this condition. In this study, we aimed to measure the antioxidant capacity in plasma samples from normotensive and preeclamptic pregnant women to evaluate their antioxidant status using a more recently developed automated measurement method. Our study group contained 42 women, 24 of whom had preeclampsia, while 18 had normotensive pregnancies. We measured the total plasma antioxidant capacity for all patients, as well as the levels of four major individual plasma antioxidant components; albumin, uric acid, ascorbic acid and bilirubin, and as a reciprocal measure, their total plasma peroxide levels. Statistically significant differences (determined using Student's t-test) were noted between the normotensive and the preeclamptic groups for their total antioxidant responses and their vitamin C levels (1.31 +/- 0.12 mmol versus 1.06 +/- 0.41 mmol Trolox eq./L; 30.2 +/- 17.83 micromol/L versus 18.1 +/- 11.37 micromol/L, respectively), which were both considerably reduced in the preeclamptic patients. In contrast, the total plasma peroxide levels were significantly elevated in this group (49.8 +/- 14.3 micromol/L versus 38.8 +/- 9.6 micromol/L). We found a decreased total antioxidant response in preeclamptic patients using a simple, rapid and reliable automated colorimetric assay, which may suitable for use in any routine clinical biochemistry laboratory, and considerably facilitates the assessment of this useful clinical parameter. We suggest that this novel method may be used as a routine test to evaluate and follow up of the levels of oxidative stress in preeclampsia.

Dexamethasone-suppressed cortisol awakening response predicts treatment outcome in posttraumatic stress disorder

NARCIS (Netherlands)

Nijdam, M. J.; van Amsterdam, J. G. C.; Gersons, B. P. R.; Olff, M.

2015-01-01

Posttraumatic stress disorder (PTSD) has been associated with several alterations in the neuroendocrine system, including enhanced cortisol suppression in response to the dexamethasone suppression test. The aim of this study was to examine whether specific biomarkers of PTSD predict treatment

Ethylene signaling renders the jasmonate response of Arabidopsis insensitive to future suppression by salicylic Acid.

Science.gov (United States)

Leon-Reyes, Antonio; Du, Yujuan; Koornneef, Annemart; Proietti, Silvia; Körbes, Ana P; Memelink, Johan; Pieterse, Corné M J; Ritsema, Tita

2010-02-01

Cross-talk between jasmonate (JA), ethylene (ET), and Salicylic acid (SA) signaling is thought to operate as a mechanism to fine-tune induced defenses that are activated in response to multiple attackers. Here, 43 Arabidopsis genotypes impaired in hormone signaling or defense-related processes were screened for their ability to express SA-mediated suppression of JA-responsive gene expression. Mutant cev1, which displays constitutive expression of JA and ET responses, appeared to be insensitive to SA-mediated suppression of the JA-responsive marker genes PDF1.2 and VSP2. Accordingly, strong activation of JA and ET responses by the necrotrophic pathogens Botrytis cinerea and Alternaria brassicicola prior to SA treatment counteracted the ability of SA to suppress the JA response. Pharmacological assays, mutant analysis, and studies with the ET-signaling inhibitor 1-methylcyclopropene revealed that ET signaling renders the JA response insensitive to subsequent suppression by SA. The APETALA2/ETHYLENE RESPONSE FACTOR transcription factor ORA59, which regulates JA/ET-responsive genes such as PDF1.2, emerged as a potential mediator in this process. Collectively, our results point to a model in which simultaneous induction of the JA and ET pathway renders the plant insensitive to future SA-mediated suppression of JA-dependent defenses, which may prioritize the JA/ET pathway over the SA pathway during multi-attacker interactions.

BWR Mark III pressure suppression containment response to hydrogen deflagration

International Nuclear Information System (INIS)

Fuls, G.M.; Gunter, A.D.

1982-01-01

The CLASIX-3 computer program has been used to evaluate the temperature and pressure response of the BWR Mark III Suppression Containment System to hydrogen deflagration resulting from a degraded core condition. The CLASIX-3 computer program is an extension of the CLASIX program which was originally developed to analyze ice condenser containments. A brief description is given of the modifications made to CLASIX to increase its flexibility and versatility to include the capability of analyzing the Mark III Containment. Analytical results are presented for the two base case transients. The two base cases are the stuck open steam relief valve and the small break LOCA, both of which are assumed to lead to a degraded core condition and the release of hydrogen to the containment. Results include pressure and temperature response, gas concentrations and suppression pool response

Herbicidal and antioxidant responses of transgenic rice overexpressing Myxococcus xanthus protoporphyrinogen oxidase.

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Jung, Sunyo; Back, Kyoungwhan

2005-05-01

We analyzed the herbicidal and antioxidant defense responses of transgenic rice plants that overexpressed the Myxococcus xanthus protoporphyrinogen oxidase gene. Leaf squares of the wild-type incubated with oxyfluorfen were characterized by necrotic leaf lesions and increases in conductivity and malonyldialdehyde levels, whereas transgenic lines M4 and M7 did not show any change with up to 100 microM oxyfluorfen. The wild-type had decreased F(v)/F(m) and produced a high level of H(2)O(2) at 18 h after foliar application of oxyfluorfen, whereas transgenic lines M4 and M7 were unaffected. In response to oxyfluorfen, violaxanthin, beta-carotene, and chlorophylls (Chls) decreased in wild-type plants, whereas antheraxanthin and zeaxanthin increased. Only a slight decline in Chls was observed in transgenic lines at 48 h after oxyfluorfen treatment. Noticeable increases of cytosolic Cu/Zn-superoxide dismutase, peroxidase isozymes 1 and 2, and catalase were observed after at 48 h of oxyfluorfen treatment in the wild-type. Non-enzymatic antioxidants appeared to respond faster to oxyfluorfen-induced photodynamic stress than did enzymatic antioxidants. Protective responses for the detoxification of active oxygen species were induced to counteract photodynamic stress in oxyfluorfen-treated, wild-type plants. However, oxyfluorfen-treated, transgenic plants suffered less oxidative stress, confirming increased herbicidal resistance resulted from dual expression of M. xanthus Protox in chloroplasts and mitochondria.

Methyl jasmonate regulates antioxidant defense and suppresses arsenic uptake in Brassica napus L.

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Muhammad A Farooq

2016-04-01

Full Text Available Methyl jasmonate (MJ is an important plant growth regulator, involved in plant defense against abiotic stresses, however its possible function in response to metal stress is poorly understood. In the present study, the effect of MJ on physiological and biochemical changes of the plants exposed to arsenic (As stress were investigated in two Brassica napus L. cultivars (ZS 758 – a black seed type, and Zheda 622 – a yellow seed type. The As treatment at 200 µM was more phytotoxic, however its combined application with MJ resulted in significant increase in leaf chlorophyll fluorescence, biomass production and reduced malondialdehyde content compared with As stressed plants. The application of MJ minimized the oxidative stress, as revealed via a lower level of reactive oxygen species (ROS synthesis (H2O2 and OH- in leaves and the maintenance of high redox states of glutathione and ascorbate. Enhanced enzymatic activities and gene expression of important antioxidants (SOD, APX, CAT, POD, secondary metabolites (PAL, PPO, CAD and induction of lypoxygenase gene suggest that MJ plays an effective role in the regulation of multiple transcriptional pathways which were involved in oxidative stress responses. The content of As was higher in yellow seeded plants (cv. Zheda 622 as compared to black seeded plants (ZS 758. The application of MJ significantly reduced the As content in leaves and roots of both cultivars. Findings of the present study reveal that MJ improves ROS scavenging through enhanced antioxidant defense system, secondary metabolite and reduced As contents in both the cultivars.

Antioxidant responses to heat and light stress differ with habitat in a common reef coral

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Hawkins, Thomas D.; Krueger, Thomas; Wilkinson, Shaun P.; Fisher, Paul L.; Davy, Simon K.

2015-12-01

Coral bleaching—the stress-induced collapse of the coral- Symbiodinium symbiosis—is a significant driver of worldwide coral reef degradation. Yet, not all corals are equally susceptible to bleaching, and we lack a clear understanding of the mechanisms underpinning their differential susceptibilities. Here, we focus on cellular redox regulation as a potential determinant of bleaching susceptibility in the reef coral Stylophora pistillata. Using slow heating (1 °C d-1) and altered irradiance, we induced bleaching in S. pistillata colonies sampled from two depths [5-8 m (shallow) and 15-18 m (deep)]. There was significant depth-dependent variability in the timing and extent of bleaching (loss of symbiont cells), as well as in host enzymatic antioxidant activity [specifically, superoxide dismutase and catalase (CAT)]. However, among the coral fragments that bleached, most did so without displaying any evidence of a host enzymatic antioxidant response. For example, both deep and shallow corals suffered significant symbiont loss at elevated temperature, but only deep colonies exposed to high temperature and high light displayed any up-regulation of host antioxidant enzyme activity (CAT). Surprisingly, this preceded the equivalent antioxidant responses of the symbiont, which raises questions about the source(s) of hydrogen peroxide in the symbiosis. Overall, changes in enzymatic antioxidant activity in the symbionts were driven primarily by irradiance rather than temperature, and responses were similar across depth groups. Taken together, our results suggest that in the absence of light stress, heating of 1 °C d-1 to 4 °C above ambient is not sufficient to induce a substantial oxidative challenge in S. pistillata. We provide some of the first evidence that regulation of coral enzymatic antioxidants can vary significantly depending on habitat, and, in terms of determining bleaching susceptibility, our results suggest a significant role for the host's differential

Interleukin-4 Supports the Suppressive Immune Responses Elicited by Regulatory T Cells

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Wei-Cheng Yang

2017-11-01

Full Text Available Interleukin-4 (IL-4 has been considered as one of the tolerogenic cytokines in many autoimmune animal models and clinical settings. Despite its role in antagonizing pathogenic Th1 responses, little is known about whether IL-4 possesses functions that affect regulatory T cells (Tregs. Tregs are specialized cells responsible for the maintenance of peripheral tolerance through their immune modulatory capabilities. Interestingly, it has been suggested that IL-4 supplement at a high concentration protects responder T cells (Tresps from Treg-mediated immune suppression. In addition, such supplement also impedes TGF-β-induced Treg differentiation in vitro. However, these phenomena may contradict the tolerogenic role of IL-4, and the effects of IL-4 on Tregs are therefore needed to be further elucidated. In this study, we utilized IL-4 knockout (KO mice to validate the role of IL-4 on Treg-mediated immune suppression. Although IL-4 KO and control animals harbor similar frequencies of Tregs, Tregs from IL-4 KO mice weakly suppressed autologous Tresp activation. In addition, IL-4 deprivation impaired the ability of Tregs to modulate immune response, whereas IL-4 supplementation reinforced IL-4 KO Tregs in their function in suppressing Tresps. Finally, the presence of IL-4 was associated with increased cell survival and granzyme expression of Tregs. These results suggest the essential role of IL-4 in supporting Treg-mediated immune suppression, which may benefit the development of therapeutic strategies for autoimmune diseases.

Response of nutrients, minerals, antioxidant leaf pigments, vitamins, polyphenol, flavonoid and antioxidant activity in selected vegetable amaranth under four soil water content.

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Sarker, Umakanta; Oba, Shinya

2018-06-30

Four selected vegetable amaranths were grown under four soil water content to evaluate their response in nutrients, minerals, antioxidant leaf pigments, vitamins, polyphenol, flavonoid and total antioxidant activity (TAC). Vegetable amaranth was significantly affected by variety, soil water content and variety × soil water content interactions for all the traits studied. Increase in water stress, resulted in significant changes in proximate compositions, minerals (macro and micro), leaf pigments, vitamin, total polyphenol content (TPC), and total flavonoid content (TFC) of vegetable amaranth. Accessions VA14 and VA16 performed better for all the traits studied. Correlation study revealed a strong antioxidant scavenging activity of leaf pigments, ascorbic acid, TPC and TFC. Vegetable amaranth can tolerate soil water stress without compromising the high quality of the final product in terms of nutrients and antioxidant profiles. Therefore, it could be a promising alternative crop in semi-arid and dry areas and also during dry seasons. Copyright © 2018. Published by Elsevier Ltd.

Skin protection against UV light by dietary antioxidants.

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Fernández-García, Elisabet

2014-09-01

There is considerable interest in the concept of additional endogenous photoprotection by dietary antioxidants. A number of efficient micronutrients are capable of contributing to the prevention of UV damage in humans. These compounds protect molecular targets by scavenging reactive oxygen species, including excited singlet oxygen and triplet state molecules, and also modulate stress-dependent signaling and/or suppress cellular and tissue responses like inflammation. Micronutrients present in the diet such as carotenoids, vitamins E and C, and polyphenols contribute to antioxidant defense and may also contribute to endogenous photoprotection. This review summarizes the literature concerning the use of dietary antioxidants as systemic photoprotective agents towards skin damage induced by UVA and UVB. Intervention studies in humans with carotenoid-rich diets have shown photoprotection. Interestingly, rather long treatment periods (a minimum of 10 weeks) were required to achieve this effect. Likewise, dietary carotenoids exert their protective antioxidant function in several in vitro and in vivo studies when present at sufficiently high concentration. A combination of vitamins E and C protects the skin against UV damage. It is suggested that daily consumption of dietary polyphenols may provide efficient protection against the harmful effects of solar UV radiation in humans. Furthermore, the use of these micronutrients in combination may provide an effective strategy for protecting human skin from damage by UV exposure.

Suppression of immune response to Lol pI by administration of idiotype.

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Boutin, Y; Hébert, J

1995-03-01

Allergic diseases are characterized by an increased production of specific IgE antibodies. Suppression of IgE antibody production may be accomplished through idiotypic manipulation. Using an animal model, we explored the effects of anti-Lol pI monoclonal antibody administration on the subsequent IgE and IgG antibody response against Lol pI. Mice were treated with an anti-Lol pI monoclonal antibody (290A-167), which resulted in the production of anti-idiotypic antibodies as evidenced by their ability to bind to the Fab fraction of 290A-167 and to inhibit the binding of rabbit polyclonal anti-idiotypic antibodies to 290A-167. The animals were then immunized with Lol pI adsorbed onto alum, and the immune response to the protein was analyzed. Antigen-specific IgG1 and IgE responses were strongly suppressed as determined by immunoassay. Suppression of anti-Lol pI IgE antibodies was confirmed by a reduction of end-point titers measured by passive cutaneous anaphylaxis. The suppression of antigen-specific antibody was accompanied by a reduction of anti-Lol pI antibody-producing spleen cells. These data indicate that pretreatment with 290A-167 can strongly downregulate the IgE response to the main allergen of ryegrass pollen, which is associated with an increase in anti-idiotypic antibodies. This approach could provide rapid, long-term hyposensitization in patients with grass pollen allergy.

Shanxi Aged Vinegar Protects against Alcohol-Induced Liver Injury via Activating Nrf2-Mediated Antioxidant and Inhibiting TLR4-Induced Inflammatory Response

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Ting Xia

2018-06-01

Full Text Available Shanxi aged vinegar (SAV is a typical fermented and antioxidant food, which has various health-promoting effects. This work aimed to explore the effects of SAV on alcohol-induced liver injury. A mice model of alcoholic liver injury was established to illuminate its potential mechanisms. All mice pretreated with SAV and then received an ethanol solution (50% w/v, 4.8 g/kg b.w.. The results showed that SAV ameliorated alcohol-induced histological changes and elevation of liver enzymes. SAV attenuated alcohol-induced oxidative stress by declining levels of hepatic oxidants, and restoring depletion of antioxidant enzyme activities in mice livers. Moreover, SAV alleviated alcohol-induced oxidative damage by activating nuclear factor erythroid-2-related factor 2 (Nrf2-mediated signal pathway. In addition, SAV prevented alcohol-induced inflammation by suppressing lipopolysaccharide (LPS level and activities of pro-inflammatory enzymes, and regulating inflammatory cytokines. SAV inhibited alcohol-induced inflammation through down-regulating the expression of Toll-like receptor 4 (TLR4-mediated inflammatory response. The findings provide crucial evidence for elucidating the hepatoprotective mechanisms of SAV and encourage the future application of SAV as a functional food for liver protection.

Dissociating the influence of response selection and task anticipation on corticospinal suppression during response preparation.

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Duque, Julie; Labruna, Ludovica; Cazares, Christian; Ivry, Richard B

2014-12-01

Motor behavior requires selecting between potential actions. The role of inhibition in response selection has frequently been examined in tasks in which participants are engaged in some advance preparation prior to the presentation of an imperative signal. Under such conditions, inhibition could be related to processes associated with response selection, or to more general inhibitory processes that are engaged in high states of anticipation. In Experiment 1, we manipulated the degree of anticipatory preparation. Participants performed a choice reaction time task that required choosing between a movement of the left or right index finger, and used transcranial magnetic stimulation (TMS) to elicit motor evoked potentials (MEPs) in the left hand agonist. In high anticipation blocks, a non-informative cue (e.g., fixation marker) preceded the imperative; in low anticipation blocks, there was no cue and participants were required to divide their attention between two tasks to further reduce anticipation. MEPs were substantially reduced before the imperative signal in high anticipation blocks. In contrast, in low anticipation blocks, MEPs remained unchanged before the imperative signal but showed a marked suppression right after the onset of the imperative. This effect occurred regardless of whether the imperative had signalled a left or right hand response. After this initial inhibition, left MEPs increased when the left hand was selected and remained suppressed when the right hand was selected. We obtained similar results in Experiment 2 except that the persistent left MEP suppression when the left hand was not selected was attenuated when the alternative response involved a non-homologous effector (right foot). These results indicate that, even in the absence of an anticipatory period, inhibitory mechanisms are engaged during response selection, possibly to prevent the occurrence of premature and inappropriate responses during a competitive selection process. Copyright

Dissociating the Influence of Response Selection and Task Anticipation on Corticospinal Suppression During Response Preparation

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Duque, Julie; Labruna, Ludovica; Cazares, Christian; Ivry, Richard B.

2014-01-01

Motor behavior requires selecting between potential actions. The role of inhibition in response selection has frequently been examined in tasks in which participants are engaged in some advance preparation prior to the presentation of an imperative signal. Under such conditions, inhibition could be related to processes associated with response selection, or to more general inhibitory processes that are engaged in high states of anticipation. In Experiment 1, we manipulated the degree of anticipatory preparation. Participants performed a choice reaction time task that required choosing between a movement of the left or right index finger, and used transcranial magnetic stimulation (TMS) to elicit motor evoked potentials (MEPs) in the left hand agonist. In high anticipation blocks, a non-informative cue (e.g., fixation marker) preceded the imperative; in low anticipation blocks, there was no cue and participants were required to divide their attention between two tasks to further reduce anticipation. MEPs were substantially reduced before the imperative signal in high anticipation blocks. In contrast, in low anticipation blocks, MEPs remained unchanged before the imperative signal but showed a marked suppression right after the onset of the imperative. This effect occurred regardless of whether the imperative had signaled a left or right hand response. After this initial inhibition, left MEPs increased when the left hand was selected and remained suppressed when the right hand was selected. We obtained similar results in Experiment 2 except that the persistent left MEP suppression when the left hand was not selected was attenuated when the alternative response involved a non-homologous effector (right foot). These results indicate that, even in the absence of an anticipatory period, inhibitory mechanisms are engaged during response selection, possibly to prevent the occurrence of premature and inappropriate responses during a competitive selection process. PMID

Ultraviolet Radiation: Cellular Antioxidant Response and the Role of Ocular Aldehyde Dehydrogenase Enzymes

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Marchitti, Satori A.; Chen, Ying; Thompson, David C.; Vasiliou, Vasilis

2011-01-01

Solar ultraviolet radiation (UVR) exposes the human eye to near constant oxidative stress. Evidence suggests that UVR is the most important environmental insult leading to the development of a variety of ophthalmoheliosis disorders. UVR-induced reactive oxygen species are highly reactive with DNA, proteins and cellular membranes, resulting in cellular and tissue damage. Antioxidant defense systems present in ocular tissues function to combat reactive oxygen species and protect the eye from oxidative damage. Important enzymatic antioxidants are the superoxide dismutases, catalase, glutathione peroxidases, glutathione reductase and members of the aldehyde dehydrogenase (ALDH) superfamily. Glutathione, ascorbic and uric acids, α-tocopherol, NADPH and ferritin serve as small molecule, nonenzymatic antioxidants. Ocular tissues have high levels of these antioxidants which are essential for the maintenance of redox homeostasis in the eye and protection against oxidative damage. ALDH1A1 and ALDH3A1, present abundantly in the cornea and lens, have been shown to have unique roles in the defense against UVR and the downstream effects of oxidative stress. This review presents the properties and functions of ocular antioxidants that play critical roles in the cellular response to UVR exposure, including a focused discussion of the unique roles that the ALDH1A1 and ALDH3A1 enzymes have as multi-functional ocular antioxidants. PMID:21670692

Optimization of Ultrasonic Extraction of Phenolic Antioxidants from Green Tea Using Response Surface Methodology

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Lee, Lan-Sook; Lee, Namhyouck; Kim, Young; Lee, Chang-Ho; Hong, Sang; Jeon, Yeo-Won; Kim, Young-Eon

2013-01-01

Response surface methodology (RSM) has been used to optimize the extraction conditions of antioxidants with relatively low caffeine content from green tea by using ultrasonic extraction. The predicted optimal conditions for the highest antioxidant activity and minimum caffeine level were found at 19.7% ethanol, 26.4 min extraction time, and 24.0 °C extraction temperature. In the predicted optimal conditions, the experimental values were very close to the predicted values. Moreover, the ratio ...

Alleviation of response suppression to conditioned aversive stimuli by lesions of the dorsal noradrenergic bundle.

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Tsaltas, E; Gray, J A; Fillenz, M

1984-08-01

Rats with neurotoxic lesions of the dorsal ascending noradrenergic bundle (DB) were compared with sham-operated (SH) controls on the acquisition, steady state and extinction of response suppression maintained by a classical (conditioned suppression) or an instrumental (discriminated punishment) contingency. DB lesions interfered neither with the acquisition of the reference response of sucrose-rewarded barpressing nor with unconditioned responding to the overhead flashing light subsequently used as a signal of shock. The acquisition of discriminated response suppression was also unaffected by the lesion under both types of contingency. However, once discriminated suppression had stabilized, both the conditioned and the discriminative stimulus used were significantly less effective in maintaining suppression in DB animals than in SH controls provided that low intensity footshock (0.2 mA) was used as the unconditioned stimulus (UCS). Upon increase of UCS intensity (to 0.5 mA) normal suppression was observed in the DB group under both contingencies. Extinction of the classical contingency reinstated the difference between DB and SH performance: DB lesion resulted in significantly faster extinction of fear. In contrast, extinction of the discriminated punishment contingency was unaffected by the lesion, although generalized response suppression dissipated faster in the DB than in the SH animals trained under this condition. Our results offer no support for the reinforcement hypothesis of DB function (normal acquisition of barpressing and of discriminated suppression of barpressing); mixed support (greater initial generalization of suppression in DB animals) and contradiction (more rapid extinction of conditioned suppression in DB animals) for the attentional hypothesis; and weak support (reduced suppression and more rapid extinction of suppression in DB animals, but only within limited experimental parameters) for the anxiety hypothesis of DB function. Hence none of

Lipidomic and Antioxidant Response to Grape Seed, Corn and Coconut Oils in Healthy Wistar Rats

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Abraham Wall-Medrano

2017-01-01

Full Text Available Specialty oils differ in fatty acid, phytosterol and antioxidant content, impacting their benefits for cardiovascular health. The lipid (fatty acid, phytosterol and antioxidant (total phenolics, radical scavenging capacity profiles of grapeseed (GSO, corn (CO and coconut (CNO oils and their physiological (triacylglycerides, total and HDL-cholesterol and antioxidant capacity (FRAP in serum and fatty acid and phytosterol hepatic deposition and genomic (HL, LCAT, ApoA-1 and SR-BP1 mRNA hepatic levels responses after their sub-chronic intake (10% diet for 28 days was examined in healthy albino rats. Fatty acid, phytosterol and antioxidant profiles differed between oils (p ≤ 0.01. Serum and hepatic triacylglycerides and total cholesterol increased (p ≤ 0.01; serum HDL-Cholesterol decreased (p < 0.05; but serum FRAP did not differ (p > 0.05 in CNO-fed rats as compared to CO or GSO groups. Hepatic phytosterol deposition was higher (+2.2 mg/g; p ≤ 0.001 in CO- than GSO-fed rats, but their fatty acid deposition was similar. All but ApoA-1 mRNA level increased in GSO-fed rats as compared to other groups (p ≤ 0.01. Hepatic fatty acid handling, but not antioxidant response, nor hepatic phytosterol deposition, could be related to a more efficient reverse-cholesterol transport in GSO-fed rats as compared to CO or CNO.

Expressive suppression and neural responsiveness to nonverbal affective cues.

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Petrican, Raluca; Rosenbaum, R Shayna; Grady, Cheryl

2015-10-01

Optimal social functioning occasionally requires concealment of one's emotions in order to meet one's immediate goals and environmental demands. However, because emotions serve an important communicative function, their habitual suppression disrupts the flow of social exchanges and, thus, incurs significant interpersonal costs. Evidence is accruing that the disruption in social interactions, linked to habitual expressive suppression use, stems not only from intrapersonal, but also from interpersonal causes, since the suppressors' restricted affective displays reportedly inhibit their interlocutors' emotionally expressive behaviors. However, expressive suppression use is not known to lead to clinically significant social impairments. One explanation may be that over the lifespan, individuals who habitually suppress their emotions come to compensate for their interlocutors' restrained expressive behaviors by developing an increased sensitivity to nonverbal affective cues. To probe this issue, the present study used functional magnetic resonance imaging (fMRI) to scan healthy older women while they viewed silent videos of a male social target displaying nonverbal emotional behavior, together with a brief verbal description of the accompanying context, and then judged the target's affect. As predicted, perceivers who reported greater habitual use of expressive suppression showed increased neural processing of nonverbal affective cues. This effect appeared to be coordinated in a top-down manner via cognitive control. Greater neural processing of nonverbal cues among perceivers who habitually suppress their emotions was linked to increased ventral striatum activity, suggestive of increased reward value/personal relevance ascribed to emotionally expressive nonverbal behaviors. These findings thus provide neural evidence broadly consistent with the hypothesized link between habitual use of expressive suppression and compensatory development of increased responsiveness to

Optimization of ultrasonic-assisted extraction of natural antioxidants from rice bran using response surface methodology.

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Tabaraki, Reza; Nateghi, Ashraf

2011-11-01

Ultrasonic technology was applied for extraction of polyphenols and antioxidants from the rice bran using ethanol as a food grade solvent. Response surface methodology (RSM) was used to optimize experimental conditions for extraction of polyphenols and antioxidants. Three independent variables such as solvent percentage (%), temperature (°C) and time (min) were studied. Effect of ethanol concentration was found to be significant on all responses. Total phenolic content (TPC) varied from 2.37 to 6.35mg gallic acid equivalent/g of dry sample. Antioxidant activity of the extracts was determined by the ferric reducing antioxidant power (FRAP) assay and scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. FRAP and DPPH values varied from 31.74 to 57.23μmol Fe(2+)/g of dry sample and 16.88% to 55.61% inhibition, respectively. Extraction yields ranged from 11 to 20.2%. Optimal ultrasonic-assisted extraction (UAE) conditions were identified as 65-67% ethanol, 51-54°C, 40-45min. The experimental values agreed with those predicted by SRM models, thus indicating suitability of the model employed and the success of RSM in optimizing the extraction conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

Relationships among alcoholic liver disease, antioxidants, and antioxidant enzymes.

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Han, Kyu-Ho; Hashimoto, Naoto; Fukushima, Michihiro

2016-01-07

Excessive consumption of alcoholic beverages is a serious cause of liver disease worldwide. The metabolism of ethanol generates reactive oxygen species, which play a significant role in the deterioration of alcoholic liver disease (ALD). Antioxidant phytochemicals, such as polyphenols, regulate the expression of ALD-associated proteins and peptides, namely, catalase, superoxide dismutase, glutathione, glutathione peroxidase, and glutathione reductase. These plant antioxidants have electrophilic activity and may induce antioxidant enzymes via the Kelch-like ECH-associated protein 1-NF-E2-related factor-2 pathway and antioxidant responsive elements. Furthermore, these antioxidants are reported to alleviate cell injury caused by oxidants or inflammatory cytokines. These phenomena are likely induced via the regulation of mitogen-activating protein kinase (MAPK) pathways by plant antioxidants, similar to preconditioning in ischemia-reperfusion models. Although the relationship between plant antioxidants and ALD has not been adequately investigated, plant antioxidants may be preventive for ALD because of their electrophilic and regulatory activities in the MAPK pathway.

Differential Action between Schisandrin A and Schisandrin B in Eliciting an Anti-Inflammatory Action: The Depletion of Reduced Glutathione and the Induction of an Antioxidant Response.

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Pou Kuan Leong

Full Text Available Schisandrin A (Sch A and schisandrin B (Sch B are active components of Schisandrae Fructus. We compared the biochemical mechanism underlying the anti-inflammatory action of Sch A and Sch B, using cultured lipopolysaccharide (LPS-stimulated RAW264.7 macrophages and concanavalin (ConA-stimulated mouse splenocytes. Pre-incubation with Sch A or Sch B produced an anti-inflammatory action in LPS-stimulated RAW264.7 cells, as evidenced by the inhibition of the pro-inflammatory c-Jun N-terminal kinases/p38 kinase/nuclear factor-κB signaling pathway as well as the suppression of various pro-inflammatory cytokines and effectors, with the extent of inhibition by Sch A being more pronounced. The greater activity of Sch A in anti-inflammatory response was associated with a greater decrease in cellular reduced glutathione (GSH level and a greater increase in glutathione S-transferase activity than corresponding changes produced by Sch B. However, upon incubation, only Sch B resulted in the activation of the nuclear factor (erythroid-derived 2-like factor 2 and the induction of a significant increase in the expression of thioredoxin (TRX in RAW264.7 cells. The Sch B-induced increase in TRX expression was associated with the suppression of pro-inflammatory cytokines and effectors in LPS-stimulated macrophages. Studies in a mouse model of inflammation (carrageenan-induced paw edema indicated that while long-term treatment with either Sch A or Sch B suppressed the extent of paw edema, only acute treatment with Sch A produced a significant degree of inhibition on the inflammatory response. Although only Sch A decreased the cellular GSH level and suppressed the release of pro-inflammatory cytokines and cell proliferation in ConA-simulated splenocytes in vitro, both Sch A and Sch B treatments, while not altering cellular GSH levels, suppressed ConA-stimulated splenocyte proliferation ex vivo. These results suggest that Sch A and Sch B may act differentially on

Activation of the ζ receptor 1 suppresses NMDA responses in rat retinal ganglion cells.

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Zhang, X-J; Liu, L-L; Jiang, S-X; Zhong, Y-M; Yang, X-L

2011-03-17

The sigma receptor 1 (σR1) has been shown to modulate the activity of several voltage- and ligand-gated channels. Using patch-clamp techniques in rat retinal slice preparations, we demonstrated that activation of σR1 by SKF10047 (SKF) or PRE-084 suppressed N-methyl-D-aspartate (NMDA) receptor-mediated current responses from both ON and OFF type ganglion cells (GCs), dose-dependently, and the effect could be blocked by the σR1 antagonist BD1047 or the σR antagonist haloperidol. The suppression by SKF of NMDA currents was abolished with pre-incubation of the G protein inhibitor GDP-β-S or the Gi/o activator mastoparan. We further explored the intracellular signaling pathway responsible for the SKF-induced suppression of NMDA responses. Application of either cAMP/the PKA inhibitor Rp-cAMP or cGMP/the PKG inhibitor KT5823 did not change the SKF-induced effect, suggesting the involvement of neither cAMP/PKA nor cGMP/PKG pathway. In contrast, suppression of NMDA responses by SKF was abolished by internal infusion of the phosphatidylinostiol-specific phospholipase C (PLC) inhibitor U73122, but not by the phosphatidylcholine-PLC inhibitor D609. SKF-induced suppression of NMDA responses was dependent on intracellular Ca2+ concentration ([Ca2+]i), as evidenced by the fact that the effect was abolished when [Ca2+]i was buffered with 10 mM BAPTA. The SKF effect was blocked by xestospongin-C/heparin, IP3 receptor antagonists, but unchanged by ryanodine/caffeine, ryanodine receptor modulators. Furthermore, application of protein kinase C inhibitors Bis IV and Gö6976 eliminated the SKF effect. These results suggest that the suppression of NMDA responses of rat retinal GCs caused by the activation of σR1 may be mediated by a distinct [Ca2+]i-dependent PLC-PKC pathway. This effect of SKF could help ameliorate malfunction of GCs caused by excessive stimulation of NMDA receptors under pathological conditions. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights

Suppression of LPS-induced inflammatory responses in macrophages infected with Leishmania

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Kelly Ben L

2010-02-01

Full Text Available Abstract Background Chronic inflammation activated by macrophage innate pathogen recognition receptors such as TLR4 can lead to a range of inflammatory diseases, including atherosclerosis, Crohn's disease, arthritis and cancer. Unlike many microbes, the kinetoplastid protozoan pathogen Leishmania has been shown to avoid and even actively suppress host inflammatory cytokine responses, such as LPS-induced IL-12 production. The nature and scope of Leishmania-mediated inflammatory cytokine suppression, however, is not well characterized. Advancing our knowledge of such microbe-mediated cytokine suppression may provide new avenues for therapeutic intervention in inflammatory disease. Methods We explored the kinetics of a range of cytokine and chemokine responses in primary murine macrophages stimulated with LPS in the presence versus absence of two clinically distinct species of Leishmania using sensitive multiplex cytokine analyses. To confirm that these effects were parasite-specific, we compared the effects of Leishmania uptake on LPS-induced cytokine expression with uptake of inert latex beads. Results Whilst Leishmania uptake alone did not induce significant levels of any cytokine analysed in this study, Leishmania uptake in the presence of LPS caused parasite-specific suppression of certain LPS-induced pro-inflammatory cytokines, including IL-12, IL-17 and IL-6. Interestingly, L. amazonensis was generally more suppressive than L. major. We also found that other LPS-induced proinflammatory cytokines, such as IL-1α, TNF-α and the chemokines MIP-1α and MCP-1 and also the anti-inflammatory cytokine IL-10, were augmented during Leishmania uptake, in a parasite-specific manner. Conclusions During uptake by macrophages, Leishmania evades the activation of a broad range of cytokines and chemokines. Further, in the presence of a strong inflammatory stimulus, Leishmania suppresses certain proinflammatory cytokine responses in a parasite

Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: involvement of the adaptive antioxidant response.

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Xue, Peng; Hou, Yongyong; Zhang, Qiang; Woods, Courtney G; Yarborough, Kathy; Liu, Huiyu; Sun, Guifan; Andersen, Melvin E; Pi, Jingbo

2011-04-08

There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 μM) inorganic arsenite (iAs³(+)) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs³(+) exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs³(+) exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4 expression may also be involved in arsenic-induced insulin resistance in adipocytes. Taken together our studies suggest that prolonged low-level iAs³(+) exposure activates the cellular adaptive oxidative stress response, which impairs insulin-stimulated ROS signaling that is involved in ISGU, and thus causes insulin resistance in adipocytes. Copyright © 2011 Elsevier Inc. All rights reserved.

Glutathione Peroxidase-1 Suppresses the Unfolded Protein Response upon Cigarette Smoke Exposure

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Patrick Geraghty

2016-01-01

Full Text Available Oxidative stress provokes endoplasmic reticulum (ER stress-induced unfolded protein response (UPR in the lungs of chronic obstructive pulmonary (COPD subjects. The antioxidant, glutathione peroxidase-1 (GPx-1, counters oxidative stress induced by cigarette smoke exposure. Here, we investigate whether GPx-1 expression deters the UPR following exposure to cigarette smoke. Expression of ER stress markers was investigated in fully differentiated normal human bronchial epithelial (NHBE cells isolated from nonsmoking, smoking, and COPD donors and redifferentiated at the air liquid interface. NHBE cells from COPD donors expressed heightened ATF4, XBP1, GRP78, GRP94, EDEM1, and CHOP compared to cells from nonsmoking donors. These changes coincided with reduced GPx-1 expression. Reintroduction of GPx-1 into NHBE cells isolated from COPD donors reduced the UPR. To determine whether the loss of GPx-1 expression has a direct impact on these ER stress markers during smoke exposure, Gpx-1−/− mice were exposed to cigarette smoke for 1 year. Loss of Gpx-1 expression enhanced cigarette smoke-induced ER stress and apoptosis. Equally, induction of ER stress with tunicamycin enhanced antioxidant expression in mouse precision-cut lung slices. Smoke inhalation also exacerbated the UPR response during respiratory syncytial virus infection. Therefore, ER stress may be an antioxidant-related pathophysiological event in COPD.

Suppression of inflammatory immune responses in celiac disease by experimental hookworm infection.

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Henry J McSorley

Full Text Available We present immunological data from two clinical trials where the effect of experimental human hookworm (Necator americanus infection on the pathology of celiac disease was evaluated. We found that basal production of Interferon- (IFN-γ and Interleukin- (IL-17A from duodenal biopsy culture was suppressed in hookworm-infected participants compared to uninfected controls. Increased levels of CD4+CD25+Foxp3+ cells in the circulation and mucosa are associated with active celiac disease. We show that this accumulation also occurs during a short-term (1 week oral gluten challenge, and that hookworm infection suppressed the increase of circulating CD4+CD25+Foxp3+ cells during this challenge period. When duodenal biopsies from hookworm-infected participants were restimulated with the immunodominant gliadin peptide QE65, robust production of IL-2, IFN-γ and IL-17A was detected, even prior to gluten challenge while participants were strictly adhering to a gluten-free diet. Intriguingly, IL-5 was produced only after hookworm infection in response to QE65. Thus we hypothesise that hookworm-induced TH2 and IL-10 cross-regulation of the TH1/TH17 inflammatory response may be responsible for the suppression of these responses during experimental hookworm infection.

Effect of "6"0Co-induced gamma radiation exposure and Jasmonic acid on antioxidant responses in Cowpea varieties

International Nuclear Information System (INIS)

Shukla, Pradeep Kumar; Bhagoji, Ravi; Ramteke, P.W.; Misra, Pragati; Maurice, Navodita

2017-01-01

Cowpea used to be the first crop harvested before the cereal crops are ready and therefore is referred to as 'hungry-season crop'. The gamma irradiation is known to increase nutritional values of food sources and also enhance and accelerate growth of certain vegetables Antioxidants are the metabolites, produced by the plant in response to different stress conditions e.g. radiation stress etc. Seeds of four cowpea varieties were treated with different doses of gamma radiation and effect of jasmonic acid (JA) on antioxidant response of cowpea was studied. The results showed that there was no linear correlation between application of JA and different antioxidant contents. (author)

How does thought-action fusion relate to responsibility attitudes and thought suppression to aggravate the obsessive-compulsive symptoms?

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Altın, Müjgan; Gençöz, Tülin

2011-01-01

Comprehensive cognitive theories of obsessive compulsive disorder (OCD) propose that clinical obsessions and compulsions arise from specific sorts of dysfunctional beliefs and appraisals, such as inflated sense of responsibility, thought-action fusion (TAF), and thought suppression. The present study aimed to examine the mediator roles of responsibility and thought suppression between TAF and obsessive-compulsive symptoms. Specifically, it aimed to explore the relative effects of TAF factors (i.e. morality and likelihood) on inflated sense of responsibility and on thought suppression to increase the obsessive qualities of intrusions. Two hundred and eighty-three Turkish undergraduate students completed a battery of measures on responsibility, thought suppression, TAF, OC symptoms, and depression. A series of hierarchical regression analyses, where depressive symptoms were controlled for, indicated that TAF-morality and TAF-likelihood follow different paths toward OC symptoms. Although TAF-morality associated with inflated sense of responsibility, TAF-likelihood associated with thought suppression efforts, and in turn these factors increased OC symptoms. These findings provide support for the critical role of sense of responsibility and thought suppression between the relationship of TAF and OC symptoms. Findings were discussed in line with the literature.

Transcriptional up-regulation of antioxidant genes by PPARδ inhibits angiotensin II-induced premature senescence in vascular smooth muscle cells

International Nuclear Information System (INIS)

Kim, Hyo Jung; Ham, Sun Ah; Paek, Kyung Shin; Hwang, Jung Seok; Jung, Si Young; Kim, Min Young; Jin, Hanna; Kang, Eun Sil; Woo, Im Sun; Kim, Hye Jung; Lee, Jae Heun; Chang, Ki Churl; Han, Chang Woo; Seo, Han Geuk

2011-01-01

Research highlights: → Activation of PPARδ by GW501516 significantly inhibited Ang II-induced premature senescence in hVSMCs. → Agonist-activated PPARδ suppressed generation of Ang II-triggered ROS with a concomitant reduction in DNA damage. → GW501516 up-regulated expression of antioxidant genes, such as GPx1, Trx1, Mn-SOD and HO-1. → Knock-down of these antioxidant genes abolished the effects of GW501516 on ROS production and premature senescence. -- Abstract: This study evaluated peroxisome proliferator-activated receptor (PPAR) δ as a potential target for therapeutic intervention in Ang II-induced senescence in human vascular smooth muscle cells (hVSMCs). Activation of PPARδ by GW501516, a specific agonist of PPARδ, significantly inhibited the Ang II-induced premature senescence of hVSMCs. Agonist-activated PPARδ suppressed the generation of Ang II-triggered reactive oxygen species (ROS) with a concomitant reduction in DNA damage. Notably, GW501516 up-regulated the expression of antioxidant genes, such as glutathione peroxidase 1, thioredoxin 1, manganese superoxide dismutase and heme oxygenase 1. siRNA-mediated down-regulation of these antioxidant genes almost completely abolished the effects of GW501516 on ROS production and premature senescence in hVSMCs treated with Ang II. Taken together, the enhanced transcription of antioxidant genes is responsible for the PPARδ-mediated inhibition of premature senescence through sequestration of ROS in hVSMCs treated with Ang II.

Dose-Response Effect of Tualang Honey on Postprandial Antioxidant Activity and Oxidative Stress in Female Athletes: A Pilot Study.

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Ahmad, Nur Syamsina; Abdul Aziz, Azlina; Kong, Kin Weng; Hamid, Mohamad Shariff A; Cheong, Jadeera Phaik Geok; Hamzah, Sareena Hanim

2017-12-01

Tualang honey (TH) contains antioxidants such as ascorbic acid, phenolic acids, and flavonoids that may be protective against oxidative stress of exercise. The aim of this study was to examine the postprandial antioxidant activity and oxidative stress after ingestion of high and low dosages of TH in female athletes. Twenty female athletes (aged 21.3 [2.1] years; body weight [BW] 54.1 [5.7] kg) were randomly assigned into two groups and consumed either 1.5 g/kg BW TH (high honey; HH; n = 10) or 0.75 g/kg BW TH (low honey; LH; n = 10). Blood sample was collected at fasting and at 0.5, 1, 2, and 3 h after TH consumption. Plasma was analyzed for total phenolic content (TPC), antioxidant activity (ferric reducing antioxidant power [FRAP]), and oxidative stress biomarkers (malondialdehyde [MDA] and reactive oxygen species [ROS]). The 3-h area under the curve (AUC) for MDA was significantly lower in the LH group compared with HH group, suggesting less oxidative stress in the LH group. However, the AUCs for TPC, FRAP, and ROS were not affected by the dosages. The concentrations of TPC and FRAP increased from baseline to 2 and 1 h after TH consumption, respectively, and concentrations returned toward baseline at 3 h in both LH and HH groups. MDA concentration significantly decreased (p antioxidant activity and suppressing oxidative stress in female athletes. The time-course effect of TH that provides optimal antioxidant activity and oxidative stress protection was between 1 and 2 h after its consumption.

Platelet activating factor receptor binding plays a critical role in jet fuel-induced immune suppression

International Nuclear Information System (INIS)

Ramos, Gerardo; Kazimi, Nasser; Nghiem, Dat X.; Walterscheid, Jeffrey P.; Ullrich, Stephen E.

2004-01-01

Applying military jet fuel (JP-8) or commercial jet fuel (Jet-A) to the skin of mice suppresses the immune response in a dose-dependant manner. The release of biological response modifiers, particularly prostaglandin E 2 (PGE 2 ), is a critical step in activating immune suppression. Previous studies have shown that injecting selective cyclooxygenase-2 inhibitors into jet fuel-treated mice blocks immune suppression. Because the inflammatory phospholipid mediator, platelet-activating factor (PAF), up-regulates cyclooxygenase-2 production and PGE 2 synthesis by keratinocytes, we tested the hypothesis that PAF-receptor binding plays a role in jet fuel-induced immune suppression. Treating keratinocyte cultures with PAF and/or jet fuel (JP-8 and Jet-A) stimulates PGE 2 secretion. Jet fuel-induced PGE 2 production was suppressed by treating the keratinocytes with specific PAF-receptor antagonists. Injecting mice with PAF, or treating the skin of the mice with JP-8, or Jet-A, induced immune suppression. Jet fuel-induced immune suppression was blocked when the jet fuel-treated mice were injected with PAF-receptor antagonists before treatment. Jet fuel treatment has been reported to activate oxidative stress and treating the mice with anti-oxidants (Vitamins C, or E or beta-hydroxy toluene), before jet fuel application, interfered with immune suppression. These findings confirm previous studies showing that PAF-receptor binding can modulate immune function. Furthermore, they suggest that PAF-receptor binding may be an early event in the induction of immune suppression by immunotoxic environmental agents that target the skin

Dimerization Controls Marburg Virus VP24-dependent Modulation of Host Antioxidative Stress Responses

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Johnson, Britney; Li, Jing; Adhikari, Jagat; Edwards, Megan R.; Zhang, Hao; Schwarz, Toni; Leung, Daisy W.; Basler, Christopher F.; Gross, Michael L.; Amarasinghe, Gaya K.

2016-08-04

Marburg virus (MARV), a member of the Filoviridae family that also includes Ebola virus (EBOV), causes lethal hemorrhagic fever with case fatality rates that have exceeded 50% in some outbreaks. Within an infected cell, there are numerous host-viral interactions that contribute to the outcome of infection. Recent studies identified MARV protein 24 (mVP24) as a modulator of the host antioxidative responses, but the molecular mechanism remains unclear. Using a combination of biochemical and mass spectrometry studies, we show that mVP24 is a dimer in solution that directly binds to the Kelch domain of Kelch-like ECH-associated protein 1 (Keap1) to regulate nuclear factor (erythroid-derived 2)-like 2 (Nrf2). This interaction between Keap1 and mVP24 occurs through the Kelch interaction loop (K-Loop) of mVP24 leading to upregulation of antioxidant response element transcription, which is distinct from other Kelch binders that regulate Nrf2 activity. N-terminal truncations disrupt mVP24 dimerization, allowing monomeric mVP24 to bind Kelch with higher affinity and stimulate higher antioxidative stress response element (ARE) reporter activity. Mass spectrometry-based mapping of the interface revealed overlapping binding sites on Kelch for mVP24 and the Nrf2 proteins. Substitution of conserved cysteines, C209 and C210, to alanine in the mVP24 K-Loop abrogates Kelch binding and ARE activation. Our studies identify a shift in the monomer-dimer equilibrium of MARV VP24, driven by its interaction with Keap1 Kelch domain, as a critical determinant that modulates host responses to pathogenic Marburg viral infections.

Addition of mushroom powder to pasta enhances the antioxidant content and modulates the predictive glycaemic response of pasta.

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Lu, Xikun; Brennan, Margaret A; Serventi, Luca; Liu, Jianfu; Guan, Wenqiang; Brennan, Charles S

2018-10-30

This study reports the effects of addition of mushroom powder on the nutritional properties, predictive in vitro glycaemic response and antioxidant potential of durum wheat pasta. Addition of the mushroom powder enriched the pasta as a source of protein, and soluble and insoluble dietary fibre compared with durum wheat semolina. Incorporation of mushroom powder significantly decreased the extent of starch degradation and the area under the curve (AUC) of reducing sugars released during digestion, while the total phenolic content and antioxidant capacities of samples increased. A mutual inhibition system between the degree of starch gelatinisation and antioxidant capacity of the pasta samples was observed. These results suggest that mushroom powder could be incorporated into fresh semolina pasta, conferring healthier characteristics, namely lowering the potential glycaemic response and improving antioxidant capacity of the pasta. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Normal mitogen-induced suppression of the interleukin-6 (IL-6) response and its deficiency in systemic lupus erythematosus

International Nuclear Information System (INIS)

Warrington, R.J.; Rutherford, W.J.

1990-01-01

A low-frequency suppressor-cell population in normal peripheral blood inhibits the B-cell CESS response to IL-6, following pokeweed mitogen stimulation. The suppression of IL-6 responsiveness is radiation sensitive, directed against CESS targets and not mediated by inhibition of IL-6 production, and associated with nonspecific cytotoxic activity against CESS targets. The generation of these cytolytic cells is also radiation sensitive. A correlation was found between PWM-induced cytotoxicity against CESS and the suppression of IL-6-dependent IgG production. But cytotoxicity toward CESS targets is not responsible for this suppression because IL-2 induces equivalent or greater nonspecific cytotoxicity against CESS in the total absence of suppression of CESS-derived IgG production and suppression is also induced by mitogen-activated PBL separated from CESS targets by a cell-impermeable membrane. This suppression was not mediated by TNF alpha/beta or IFN-gamma. In systemic lupus erythematosus, suppression of IL-6-dependent IgG production is impaired in patients with active disease (29.2 +/- 13.7%) compared to patients with inactive disease (70 +/- 19.5%) or normal controls (82.8 +/- 9.2%). There is also a defect in mitogen-induced nonspecific cytotoxicity in active SLE (specific lysis 15.1 +/- 3.5%, compared to 34 +/- 4% in normals). Pokeweed mitogen-activated PBL can therefore normally induce suppression of B-cell IL-6 responses and this response is deficient in lupus

Caffeine and sleep-deprivation mediated changes in open-field behaviours, stress response and antioxidant status in mice.

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Onaolapo, J Olakunle; Onaolapo, Y Adejoke; Akanmu, A Moses; Olayiwola, Gbola

2016-01-01

Effects of daily caffeine consumption on open-field behaviours, serum corticosterone and brain antioxidant levels were investigated after six hours of total sleep-deprivation in prepubertal mice. We tested the hypothesis that daily caffeine consumption may significantly alter behaviour, stress and antioxidative response of prepubertal mice to an acute episode of total sleep-deprivation. Prepubertal Swiss mice of both sexes were assigned to two main groups of 120 each (subdivided into 6 groups of 10 each, based on sex), and administered vehicle or graded oral doses of caffeine (10, 20, 40, 80 and 120 mg/kg/day) for 14 days. On day 14, a main group was subjected to 6 h of total sleep-deprivation by 'gentle-handling'. Open-field behaviours were then assessed in both groups, after which animals were euthanized, and levels of corticosterone, superoxide dismutase and glutathione peroxidase assayed. Horizontal locomotion, rearing and grooming increased significantly, compared to control, with sleep-deprived (SD) mice showing stronger caffeine-driven responses at higher doses; and SD female mice showing sustained response to caffeine, compared to respective males. Plasma corticosterone increased with increasing doses of caffeine in both non sleep-deprived (NSD) and SD mice; although SD mice had higher corticosterone levels. Sleep-deprivation and/or higher doses of caffeine were associated with derangements in brain antioxidant levels. Repeated caffeine consumption and/or acute sleep-deprivation led to significant changes in pattern of open-field behaviour and stress/antioxidant response in mice. Responses seen in the study are probably due to modulatory effects of caffeine on the total body response to stressful stimuli.

Selenium antagonizes cadmium-induced apoptosis in chicken spleen but not involving Nrf2-regulated antioxidant response.

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Chen, Menghao; Li, Xiaojing; Fan, Ruifeng; Cao, Changyu; Yao, Haidong; Xu, Shiwen

2017-11-01

The nuclear transcription factor NF-E2-related factor 2 (Nrf2) binds to antioxidant response elements (AREs) and is involved in the regulation of genes participated in defending cells against oxidative damage, which have been confirmed in animal models. Selenium (Se), known as an important element in the regulation of antioxidant activity, can antagonize Cadmium (Cd) toxicity in birds. However, the role of Nrf2 in selenium-cadmium interaction has not been reported in birds. To further explore the mechanism of selenium attenuating spleen toxicity induced by cadmium in chickens, cadmium chloride (CdCl 2 , 150mg/kg) and sodium selenite (Na 2 SeO 3 , 2mg/kg) were co-administrated or individually administered in the diet of chickens for 90 days. The results showed that Cd exposure increased the level of hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) and decreased the antioxidant enzyme activities, including superoxide dismutase (SOD), glutathione peroxidase (Gpx), total antioxidative capacity (T-AOC), catalase (CAT). Cd exposure increased obviously nuclear accumulation of Nrf2, and the expression of Nrf2 downstream heme oxygenase-1 (HO-1) and NAD(P)H: quinine oxidoreductase 1 (NQO1), reduced the expression of Kelch-like ECH-associated protein (keap1), Gpx-1 and thioredoxin reductase-1 (TrxR1). In addition, Cd induced the increase of bak, caspase9, p53, Cyt c mRNA levels, increased bax/bcl-2 ratio, increased caspase3 mRNA and protein levels. Selenium treatment reduced the accumulation of Cd in the spleen, attenuates Cd-induced Nrf2 nuclear accumulation, enhanced antioxidant enzyme activities, ameliorated Cd-induced oxidative stress and apoptosis in the spleen. In summary, our results demonstrate that Se ameliorated spleen toxicity induced by cadmium by modulating the antioxidant system, independently of Nrf2-regulated antioxidant response pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

Ulva lactuca polysaccharides prevent Wistar rat breast carcinogenesis through the augmentation of apoptosis, enhancement of antioxidant defense system, and suppression of inflammation

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Abd-Ellatef GF

2017-02-01

Full Text Available Gamal-Eldein F Abd-Ellatef,1 Osama M Ahmed,2 Eman S Abdel-Reheim,2 Abdel-Hamid Z Abdel-Hamid,1 1Pharmaceutical and Drug Industries Research Division, Therapeutic Chemistry Department, National Research Centre, Cairo, Egypt; 2Division of Physiology, Department of Zoology, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt Background: Recently, several research studies have been focused on the isolation and function of the polysaccharides derived from different algal species, which revealed multiple biological activities such as antioxidant and antitumor activities. This study assesses the possible breast cancer chemopreventive properties of common seaweeds, sea lettuce, Ulva lactuca (ulvan polysaccharides using in vitro bioassays on human breast cancer cell line (MCF-7 and an in vivo animal model of breast carcinogenesis. Methods: Cytotoxic effect of ulvan polysaccharides on MCF-7 was tested in vitro. For an in vivo investigation, a single dose of 25 mg/kg body weight 7,12-dimethylbenz[a]anthracene (DMBA and ulvan polysaccharides (50 mg/kg body weight every other day for 10 weeks were administered orally to the Wistar rats. Results: Deleterious histopathological alterations in breast tissues including papillary cyst adenoma and hyperplasia of ductal epithelial lining with intraluminal necrotic materials and calcifications were observed in the DMBA-administered group. These lesions were prevented in the DMBA-administered group treated with ulvan polysaccharides. The immunohistochemical sections depicted that the treatment of DMBA-administered rats with ulvan polysaccharides markedly increased the lowered pro-apoptotic protein, p53, and decreased the elevated anti-apoptotic marker, bcl2, expression in the breast tissue. The elevated lipid peroxidation and the suppressed antioxidant enzyme activities in DMBA-administered control were significantly prevented by the treatment with ulvan polysaccharides. The elevated levels of inflammatory

Circadian time-dependent antioxidant and inflammatory responses to acute cadmium exposure in the brain of zebrafish

International Nuclear Information System (INIS)

Zheng, Jia-Lang; Yuan, Shuang-Shuang; Wu, Chang-Wen; Lv, Zhen-Ming; Zhu, Ai-Yi

2017-01-01

Highlights: • Gene changed at mRNA, protein and activity levels between exposure time points. • ROS mediated antioxidant and inflammatory responses by Nrf2 and NF-κB. • The effect of time of day on Cd-induced toxicity should not be neglected in fish. - Abstract: Up to date, little information is available on effects of circadian rhythm on metal-induced toxicity in fish. In this study, zebrafish were acutely exposed to 0.97 mg L"−"1 cadmium for 12 h either at ZT0 (the light intensity began to reached maximum) or at ZT12 (light intensity began to reached minimum) to evaluate the temporal sensitivity of oxidative stress and inflammatory responses in the brain of zebrafish. Profiles of responses of some genes at mRNA, protein and activity levels were different between ZT0 and ZT12 in the normal water. Exposure to Cd induced contrary antioxidant responses and similar inflammatory responses between ZT0 and ZT12. However, the number of inflammatory genes which were up-regulated was significantly greater at ZT12 than at ZT0. And, the up-regulated inflammatory genes were more responsive at ZT12 than at ZT0. At ZT12, antioxidant genes were down-regulated at mRNA, protein and activity levels. Contrarily, antioxidant genes were not affected at mRNA levels but activated at the protein and/or activity levels at ZT0. Reactive oxygen species (ROS) sharply increased and remained relatively stable when fish were exposed to Cd at ZT12 and ZT0, respectively. Positive correlations between ROS levels and mRNA levels of nuclear transcription factor κB (NF-κB) and between mRNA levels of NF-κB and its target genes were observed, suggesting that ROS may play an essential role in regulating the magnitude of inflammatory responses. Taken together, oxidative stress and immunotoxicity in the brain were more serious when fish were exposed to Cd in the evening than in the morning, highlighting the importance of circadian rhythm in Cd-induced neurotoxicity in fish.

Role of Antioxidants and Natural Products in Inflammation

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Palanisamy Arulselvan

2016-01-01

Full Text Available Inflammation is a comprehensive array of physiological response to a foreign organism, including human pathogens, dust particles, and viruses. Inflammations are mainly divided into acute and chronic inflammation depending on various inflammatory processes and cellular mechanisms. Recent investigations have clarified that inflammation is a major factor for the progression of various chronic diseases/disorders, including diabetes, cancer, cardiovascular diseases, eye disorders, arthritis, obesity, autoimmune diseases, and inflammatory bowel disease. Free radical productions from different biological and environmental sources are due to an imbalance of natural antioxidants which further leads to various inflammatory associated diseases. In this review article, we have outlined the inflammatory process and its cellular mechanisms involved in the progression of various chronic modern human diseases. In addition, we have discussed the role of free radicals-induced tissue damage, antioxidant defence, and molecular mechanisms in chronic inflammatory diseases/disorders. The systematic knowledge regarding the role of inflammation and its associated adverse effects can provide a clear understanding in the development of innovative therapeutic targets from natural sources that are intended for suppression of various chronic inflammations associated diseases.

Autophagy as an essential cellular antioxidant pathway in neurodegenerative disease

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Samantha Giordano

2014-01-01

Full Text Available Oxidative stress including DNA damage, increased lipid and protein oxidation, are important features of aging and neurodegeneration suggesting that endogenous antioxidant protective pathways are inadequate or overwhelmed. Importantly, oxidative protein damage contributes to age-dependent accumulation of dysfunctional mitochondria or protein aggregates. In addition, environmental toxins such as rotenone and paraquat, which are risk factors for the pathogenesis of neurodegenerative diseases, also promote protein oxidation. The obvious approach of supplementing the primary antioxidant systems designed to suppress the initiation of oxidative stress has been tested in animal models and positive results were obtained. However, these findings have not been effectively translated to treating human patients, and clinical trials for antioxidant therapies using radical scavenging molecules such as α-tocopherol, ascorbate and coenzyme Q have met with limited success, highlighting several limitations to this approach. These could include: (1 radical scavenging antioxidants cannot reverse established damage to proteins and organelles; (2 radical scavenging antioxidants are oxidant specific, and can only be effective if the specific mechanism for neurodegeneration involves the reactive species to which they are targeted and (3 since reactive species play an important role in physiological signaling, suppression of endogenous oxidants maybe deleterious. Therefore, alternative approaches that can circumvent these limitations are needed. While not previously considered an antioxidant system we propose that the autophagy-lysosomal activities, may serve this essential function in neurodegenerative diseases by removing damaged or dysfunctional proteins and organelles.

The phytochemical, antibacterial and antioxidant activity of five ...

African Journals Online (AJOL)

bassie

2012-08-23

Aug 23, 2012 ... suppression and allergic reactions (Ahmad et al., 1998). There is an increased .... presence of antioxidant compounds was detected by yellow spots against a purple ... and animals (McGaw and Eloff, 2008). A literature survey.

Suppression of the cutaneous immune response following topical application of the prostaglandin PGE2

International Nuclear Information System (INIS)

Rheins, L.A.; Barnes, L.; Amornsiripanitch, S.; Collins, C.E.; Nordlund, J.J.

1987-01-01

UVB irradiation (290-320 nm) and topical applications of arachidonic acid (AA) in mice decrease the number of identifiable Langerhans cells and alter the cutaneous immune response. Application of contact allergens such as dinitrofluorobenzene (DNFB) to irradiated or AA-treated skin induces antigen-specific tolerance. Indomethacin (IM), a cyclooxygenase inhibitor, administered orally to mice prior to UVB irradiation or prior to the topical application of arachidonic acid, abrogates suppression of contact hypersensitivity (CHS) to DNFB. This suggests a byproduct of arachidonic acid generated through the cyclooxygenase pathway may be involved in the immune suppression. Topical application of various prostaglandins (PGE2, PGD2, PGF2 alpha, and CTXA2) did not cause alterations in the population density of the identifiable Ia+ dendritic Langerhans cells. PGE2, but no other tested agent, produced a suppression of the CHS response to DNFB. These observations suggests that of the various prostaglandins, PGE2 might be one of several biochemical signals which mediate the suppression of contact hypersensitivity reactions following ultraviolet radiation exposure. However, the mechanisms by which PGE2 produces its suppressive effects have not been identified

Measurement of the total antioxidant response using a novel automated method in subjects with nonalcoholic steatohepatitis

OpenAIRE

Horoz, Mehmet; Bolukbas, Cengiz; Bolukbas, Fusun F; Sabuncu, Tevfik; Aslan, Mehmet; Sarifakiogullari, Serpil; Gunaydin, Necla; Erel, Ozcan

2005-01-01

Abstract Background Oxidative stress, an increase in oxidants and/or a decrease in antioxidant capacity, is one of the potential biochemical mechanisms involved in the pathogenesis of nonalcoholic steatohepatitis. We aimed to investigate the total antioxidant response using a novel automated method in nonalcoholic steatohepatitis subjects. As a reciprocal measure, we also aimed to determine total peroxide level in the same plasma samples. Methods Twenty-two subjects with biopsy proven nonalco...

Curcumin Pretreatment Induces Nrf2 and an Antioxidant Response and Prevents Hemin-Induced Toxicity in Primary Cultures of Cerebellar Granule Neurons of Rats

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Susana González-Reyes

2013-01-01

Full Text Available Curcumin is a bifunctional antioxidant derived from Curcuma longa. This study identifies curcumin as a neuroprotectant against hemin-induced damage in primary cultures of cerebellar granule neurons (CGNs of rats. Hemin, the oxidized form of heme, is a highly reactive compound that induces cellular injury. Pretreatment of CGNs with 5–30 μM curcumin effectively increased by 2.3–4.9 fold heme oxygenase-1 (HO-1 expression and by 5.6–14.3-fold glutathione (GSH levels. Moreover, 15 μM curcumin attenuated by 55% the increase in reactive oxygen species (ROS production, by 94% the reduction of GSH/glutathione disulfide (GSSG ratio, and by 49% the cell death induced by hemin. The inhibition of heme oxygenase system or GSH synthesis with tin mesoporphyrin and buthionine sulfoximine, respectively, suppressed the protective effect of curcumin against hemin-induced toxicity. These data strongly suggest that HO-1 and GSH play a major role in the protective effect of curcumin. Furthermore, it was found that 24 h of incubation with curcumin increases by 1.4-, 2.3-, and 5.2-fold the activity of glutathione reductase, glutathione S-transferase and superoxide dismutase, respectively. Additionally, it was found that curcumin was capable of inducing nuclear factor (erythroid-derived 2-like 2 (Nrf2 translocation into the nucleus. These data suggest that the pretreatment with curcumin induces Nrf2 and an antioxidant response that may play an important role in the protective effect of this antioxidant against hemin-induced neuronal death.

Curcumin Pretreatment Induces Nrf2 and an Antioxidant Response and Prevents Hemin-Induced Toxicity in Primary Cultures of Cerebellar Granule Neurons of Rats

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González-Reyes, Susana; Guzmán-Beltrán, Silvia; Medina-Campos, Omar Noel; Pedraza-Chaverri, José

2013-01-01

Curcumin is a bifunctional antioxidant derived from Curcuma longa. This study identifies curcumin as a neuroprotectant against hemin-induced damage in primary cultures of cerebellar granule neurons (CGNs) of rats. Hemin, the oxidized form of heme, is a highly reactive compound that induces cellular injury. Pretreatment of CGNs with 5–30 μM curcumin effectively increased by 2.3–4.9 fold heme oxygenase-1 (HO-1) expression and by 5.6–14.3-fold glutathione (GSH) levels. Moreover, 15 μM curcumin attenuated by 55% the increase in reactive oxygen species (ROS) production, by 94% the reduction of GSH/glutathione disulfide (GSSG) ratio, and by 49% the cell death induced by hemin. The inhibition of heme oxygenase system or GSH synthesis with tin mesoporphyrin and buthionine sulfoximine, respectively, suppressed the protective effect of curcumin against hemin-induced toxicity. These data strongly suggest that HO-1 and GSH play a major role in the protective effect of curcumin. Furthermore, it was found that 24 h of incubation with curcumin increases by 1.4-, 2.3-, and 5.2-fold the activity of glutathione reductase, glutathione S-transferase and superoxide dismutase, respectively. Additionally, it was found that curcumin was capable of inducing nuclear factor (erythroid-derived 2)-like 2 (Nrf2) translocation into the nucleus. These data suggest that the pretreatment with curcumin induces Nrf2 and an antioxidant response that may play an important role in the protective effect of this antioxidant against hemin-induced neuronal death. PMID:24454990

Overcompensation of herbivore reproduction through hyper-suppression of plant defenses in response to competition.

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Schimmel, Bernardus C J; Ataide, Livia M S; Chafi, Rachid; Villarroel, Carlos A; Alba, Juan M; Schuurink, Robert C; Kant, Merijn R

2017-06-01

Spider mites are destructive arthropod pests on many crops. The generalist herbivorous mite Tetranychus urticae induces defenses in tomato (Solanum lycopersicum) and this constrains its fitness. By contrast, the Solanaceae-specialist Tetranychus evansi maintains a high reproductive performance by suppressing tomato defenses. Tetranychus evansi outcompetes T. urticae when infesting the same plant, but it is unknown whether this is facilitated by the defenses of the plant. We assessed the extent to which a secondary infestation by a competitor affects local plant defense responses (phytohormones and defense genes), mite gene expression and mite performance. We observed that T. evansi switches to hyper-suppression of defenses after its tomato host is also invaded by its natural competitor T. urticae. Jasmonate (JA) and salicylate (SA) defenses were suppressed more strongly, albeit only locally at the feeding site of T. evansi, upon introduction of T. urticae to the infested leaflet. The hyper-suppression of defenses coincided with increased expression of T. evansi genes coding for salivary defense-suppressing effector proteins and was paralleled by an increased reproductive performance. Together, these observations suggest that T. evansi overcompensates its reproduction through hyper-suppression of plant defenses in response to nearby competitors. We hypothesize that the competitor-induced overcompensation promotes competitive population growth of T. evansi on tomato. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Hormetic response triggers multifaceted anti-oxidant strategies in immature king penguins (Aptenodytes patagonicus).

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Rey, Benjamin; Dégletagne, Cyril; Bodennec, Jacques; Monternier, Pierre-Axel; Mortz, Mathieu; Roussel, Damien; Romestaing, Caroline; Rouanet, Jean-Louis; Tornos, Jeremy; Duchamp, Claude

2016-08-01

Repeated deep dives are highly pro-oxidative events for air-breathing aquatic foragers such as penguins. At fledging, the transition from a strictly terrestrial to a marine lifestyle may therefore trigger a complex set of anti-oxidant responses to prevent chronic oxidative stress in immature penguins but these processes are still undefined. By combining in vivo and in vitro approaches with transcriptome analysis, we investigated the adaptive responses of sea-acclimatized (SA) immature king penguins (Aptenodytes patagonicus) compared with pre-fledging never-immersed (NI) birds. In vivo, experimental immersion into cold water stimulated a higher thermogenic response in SA penguins than in NI birds, but both groups exhibited hypothermia, a condition favouring oxidative stress. In vitro, the pectoralis muscles of SA birds displayed increased oxidative capacity and mitochondrial protein abundance but unchanged reactive oxygen species (ROS) generation per g tissue because ROS production per mitochondria was reduced. The genes encoding oxidant-generating proteins were down-regulated in SA birds while mRNA abundance and activity of the main antioxidant enzymes were up-regulated. Genes encoding proteins involved in repair mechanisms of oxidized DNA or proteins and in degradation processes were also up-regulated in SA birds. Sea life also increased the degree of fatty acid unsaturation in muscle mitochondrial membranes resulting in higher intrinsic susceptibility to ROS. Oxidative damages to protein or DNA were reduced in SA birds. Repeated experimental immersions of NI penguins in cold-water partially mimicked the effects of acclimatization to marine life, modified the expression of fewer genes related to oxidative stress but in a similar way as in SA birds and increased oxidative damages to DNA. It is concluded that the multifaceted plasticity observed after marine life may be crucial to maintain redox homeostasis in active tissues subjected to high pro-oxidative pressure

Molecular mechanisms of plant response to ionising radiation. Exploration of the glucosinolate role in the anti-oxidative response

International Nuclear Information System (INIS)

Gicquel, M.

2012-01-01

Terrestrial organisms are exposed to low doses of ionising radiation from natural or anthropogenic sources. The major effects of the radiations are due to DNA deterioration and water radiolysis which generates an oxidative stress by free radical production. Plants constitute good models to study the effects of ionising radiations and the search of antioxidant molecules because of their important secondary metabolism. Thus this thesis, funded by the Brittany region, characterized the physiological and molecular response of the model plant Arabidopsis thaliana to low (10 Gy) and moderate (40 Gy) doses of ionising radiation, and was therefore interested in glucosinolates, characteristic compounds of the Brassicaceae family. The global proteomic and transcriptomic studies carried out on this model revealed (1) a common response for both doses dealing with the activation of DNA repair mechanisms, cell cycle regulation and protection of cellular structures; (2) an adjustment of the energetic metabolism and an activation of secondary compounds biosynthesis (i.e. glucosinolates and flavonoids) after the 10 Gy dose; (3) an induction of enzymatic control of ROS, the regulation of cellular components recycling and of programmed cell death after the 40 Gy dose. The potential anti-oxidative role of glucosinolates was then explored. The in vitro anti-oxidative power of some glucosinolates and their derivative products were demonstrated. Their modulating effects against irradiation-induced damages were then tested in vivo by simple experimental approaches. The importance of the glucosinolate level to give a positive or negative effect was demonstrated. (author)

Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: Involvement of the adaptive antioxidant response

International Nuclear Information System (INIS)

Xue, Peng; Hou, Yongyong; Zhang, Qiang; Woods, Courtney G.; Yarborough, Kathy; Liu, Huiyu; Sun, Guifan; Andersen, Melvin E.; Pi, Jingbo

2011-01-01

Highlights: → In 3T3-L1 adipocytes iAs 3+ decreases insulin-stimulated glucose uptake. → iAs 3+ attenuates insulin-induced phosphorylation of AKT S473. → iAs 3+ activates the cellular adaptive oxidative stress response. → iAs 3+ impairs insulin-stimulated ROS signaling. → iAs 3+ decreases expression of adipogenic genes and GLUT4. -- Abstract: There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 μM) inorganic arsenite (iAs 3+ ) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs 3+ exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs 3+ exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4 expression may also be involved in arsenic-induced insulin resistance in

Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: Involvement of the adaptive antioxidant response

Energy Technology Data Exchange (ETDEWEB)

Xue, Peng [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); School of Public Health, China Medical University, Shenyang 110001 (China); Hou, Yongyong; Zhang, Qiang; Woods, Courtney G.; Yarborough, Kathy; Liu, Huiyu [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Sun, Guifan [School of Public Health, China Medical University, Shenyang 110001 (China); Andersen, Melvin E. [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Pi, Jingbo, E-mail: jpi@thehamner.org [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States)

2011-04-08

Highlights: {yields} In 3T3-L1 adipocytes iAs{sup 3+} decreases insulin-stimulated glucose uptake. {yields} iAs{sup 3+} attenuates insulin-induced phosphorylation of AKT S473. {yields} iAs{sup 3+} activates the cellular adaptive oxidative stress response. {yields} iAs{sup 3+} impairs insulin-stimulated ROS signaling. {yields} iAs{sup 3+} decreases expression of adipogenic genes and GLUT4. -- Abstract: There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 {mu}M) inorganic arsenite (iAs{sup 3+}) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs{sup 3+} exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs{sup 3+} exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4

Andrographolide suppresses preadipocytes proliferation through glutathione antioxidant systems abrogation.

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Chen, Wei; Su, Hongming; Feng, Lina; Zheng, Xiaodong

2016-07-01

Oxidative stress is considered to play a profound role in lipid storage and whole-body energy homeostasis. Inhibition of preadipocytes proliferation by natural products is one of the strategies to prevent obesity. Andrographolide, a small molecule, has been reported to possess versatile bioactivities. However, molecular mechanism underlying the potential effect of andrographolide on preadipocytes proliferation remains obscure. In the present study, 3T3-L1 preadipocytes were employed to determine whether andrographolide could affect the proliferation of preadipocytes. Our results demonstrated andrographolide suppressed 3T3-L1 preadipocytes proliferation. The casual relationship analysis indicated that andrographolide (10 and 20μg/ml) appeared to exert the proliferation inhibitory effect through suppression of glutathione peroxidase 1 (GPX1) activity and depleting GSH by promoting its efflux in 3T3-L1 preadipocytes, which subsequently resulted in 2.06-2.41 fold increase in ROS accumulation. Excessive ROS eruption could account for oxidative damage to mitochondrial membranes as well as ultimately inhibition of cell proliferation. Taken together, our study reveals that suppression of GPX1 and GSH depletion by andrographolide seems to play a critical role in the inhibition of 3T3-L1 preadipocytes proliferation, which might have implication for obesity prevention and treatment. Copyright © 2016 Elsevier Inc. All rights reserved.

Hericium erinaceus Inhibits TNF-α-Induced Angiogenesis and ROS Generation through Suppression of MMP-9/NF-κB Signaling and Activation of Nrf2-Mediated Antioxidant Genes in Human EA.hy926 Endothelial Cells

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Hebron C. Chang

2016-01-01

Full Text Available Hericium erinaceus (HE is an edible mushroom that has been shown to exhibit anticancer and anti-inflammatory activities. We investigated the antiangiogenic and antioxidant potentials of ethanol extracts of HE in human endothelial (EA.hy926 cells upon tumor necrosis factor-α- (TNF-α- stimulation (10 ng/mL. The underlying molecular mechanisms behind the pharmacological efficacies were elucidated. We found that noncytotoxic concentrations of HE (50–200 μg/mL significantly inhibited TNF-α-induced migration/invasion and capillary-like tube formation of endothelial cells. HE treatment suppressed TNF-α-induced activity and/or overexpression of matrix metalloproteinase-9 (MMP-9 and intercellular adhesion molecule-1 (ICAM-1. Furthermore, HE downregulated TNF-α-induced nuclear translocation and transcriptional activation of nuclear factor-κB (NF-κB followed by suppression of I-κB (inhibitor-κB degradation. Data from fluorescence microscopy illustrated that increased intracellular ROS production upon TNF-α-stimulation was remarkably inhibited by HE pretreatment in a dose-dependent manner. Notably, HE triggered antioxidant gene expressions of heme oxygenase-1 (HO-1, γ-glutamylcysteine synthetase (γ-GCLC, and glutathione levels, which may contribute to inhibition of ROS. Increased antioxidant status was associated with upregulated nuclear translocation and transcriptional activation of NF-E2 related factor-2 (Nrf2 in HE treated cells. Our findings conclude that antiangiogenic and anti-inflammatory activities of H. erinaceus may contribute to its anticancer property through modulation of MMP-9/NF-κB and Nrf2-antioxidant signaling pathways.

Hericium erinaceus Inhibits TNF-α-Induced Angiogenesis and ROS Generation through Suppression of MMP-9/NF-κB Signaling and Activation of Nrf2-Mediated Antioxidant Genes in Human EA.hy926 Endothelial Cells.

Science.gov (United States)

Chang, Hebron C; Yang, Hsin-Ling; Pan, Jih-Hao; Korivi, Mallikarjuna; Pan, Jian-You; Hsieh, Meng-Chang; Chao, Pei-Min; Huang, Pei-Jane; Tsai, Ching-Tsan; Hseu, You-Cheng

2016-01-01

Hericium erinaceus (HE) is an edible mushroom that has been shown to exhibit anticancer and anti-inflammatory activities. We investigated the antiangiogenic and antioxidant potentials of ethanol extracts of HE in human endothelial (EA.hy926) cells upon tumor necrosis factor-α- (TNF-α-) stimulation (10 ng/mL). The underlying molecular mechanisms behind the pharmacological efficacies were elucidated. We found that noncytotoxic concentrations of HE (50-200 μg/mL) significantly inhibited TNF-α-induced migration/invasion and capillary-like tube formation of endothelial cells. HE treatment suppressed TNF-α-induced activity and/or overexpression of matrix metalloproteinase-9 (MMP-9) and intercellular adhesion molecule-1 (ICAM-1). Furthermore, HE downregulated TNF-α-induced nuclear translocation and transcriptional activation of nuclear factor-κB (NF-κB) followed by suppression of I-κB (inhibitor-κB) degradation. Data from fluorescence microscopy illustrated that increased intracellular ROS production upon TNF-α-stimulation was remarkably inhibited by HE pretreatment in a dose-dependent manner. Notably, HE triggered antioxidant gene expressions of heme oxygenase-1 (HO-1), γ-glutamylcysteine synthetase (γ-GCLC), and glutathione levels, which may contribute to inhibition of ROS. Increased antioxidant status was associated with upregulated nuclear translocation and transcriptional activation of NF-E2 related factor-2 (Nrf2) in HE treated cells. Our findings conclude that antiangiogenic and anti-inflammatory activities of H. erinaceus may contribute to its anticancer property through modulation of MMP-9/NF-κB and Nrf2-antioxidant signaling pathways.

Antioxidative and immunological responses in the haemolymph of wolf spider Xerolycosa nemoralis (Lycosidae) exposed to starvation and dimethoate

International Nuclear Information System (INIS)

Stalmach, Monika; Wilczek, Grażyna; Homa, Joanna; Szulinska, Elżbieta

2015-01-01

The aim of this study was to assess the intensity of enzymatic antioxidative parameters [catalase (CAT), glutathione peroxidase (GSTPx), glutathione reductase (GR), total antioxidant capacity (TAC)] and percentage of high granularity cells as well as low to medium granularity cells in haemolymph of wolf spiders Xerolycosa nemoralis exposed to starvation and dimethoate under laboratory conditions. Only in starved males, haemolymph included a lower percentage of high granularity cells, accompanied by high activity of CAT and GSTPx, than in the control. Exposure of males to dimethoate increased CAT activity, after single application, and significantly enhanced GR activity, after five-time application. In females, five-time contact with dimethoate elevated the percentage of high granularity cells. As in comparison to females, male X. nemoralis were more sensitive to the applied stressing factors, it may be concluded that in natural conditions both food deficiency and chemical stress may diminish the immune response of their organisms. - Highlights: • Starvation of males diminishes their immunological potential. • Females, compared with males, are less sensitive to starvation and dimethoate. • Antioxidative responses are stronger in starvation than after dimethoate intoxication. - The level of antioxidative response and quantitative changes of haemocytes in the haemolymph of wolf spider Xerolycosa nemoralis (Lycosidae) depend on the stressor and gender.

Kallikrein–Kinin System Suppresses Type I Interferon Responses: A Novel Pathway of Interferon Regulation

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Alecia Seliga

2018-02-01

Full Text Available The Kallikrein–Kinin System (KKS, comprised of kallikreins (klks, bradykinins (BKs angiotensin-converting enzyme (ACE, and many other molecules, regulates a number of physiological processes, including inflammation, coagulation, angiogenesis, and control of blood pressure. In this report, we show that KKS regulates Type I IFN responses, thought to be important in lupus pathogenesis. We used CpG (TLR9 ligand, R848 (TLR7 ligand, or recombinant IFN-α to induce interferon-stimulated genes (ISGs and proteins, and observed that this response was markedly diminished by BKs, klk1 (tissue kallikrein, or captopril (an ACE inhibitor. BKs significantly decreased the ISGs induced by TLRs in vitro and in vivo (in normal and lupus-prone mice, and in human PBMCs, especially the induction of Irf7 gene (p < 0.05, the master regulator of Type I IFNs. ISGs induced by IFN-α were also suppressed by the KKS. MHC Class I upregulation, a classic response to Type I IFNs, was reduced by BKs in murine dendritic cells (DCs. BKs decreased phosphorylation of STAT2 molecules that mediate IFN signaling. Among the secreted pro-inflammatory cytokines/chemokines analyzed (IL-6, IL12p70, and CXCL10, the strongest suppressive effect was on CXCL10, a highly Type I IFN-dependent cytokine, upon CpG stimulation, both in normal and lupus-prone DCs. klks that break down into BKs, also suppressed CpG-induced ISGs in murine DCs. Captopril, a drug that inhibits ACE and increases BK, suppressed ISGs, both in mouse DCs and human PBMCs. The effects of BK were reversed with indomethacin (compound that inhibits production of PGE2, suggesting that BK suppression of IFN responses may be mediated via prostaglandins. These results highlight a novel regulatory mechanism in which members of the KKS control the Type I IFN response and suggest a role for modulators of IFNs in the pathogenesis of lupus and interferonopathies.

Caffeine and sleep-deprivation mediated changes in open-field behaviours, stress response and antioxidant status in mice

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J. Olakunle Onaolapo

2016-07-01

Conclusion: Repeated caffeine consumption and/or acute sleep-deprivation led to significant changes in pattern of open-field behaviour and stress/antioxidant response in mice. Responses seen in the study are probably due to modulatory effects of caffeine on the total body response to stressful stimuli.

Circadian time-dependent antioxidant and inflammatory responses to acute cadmium exposure in the brain of zebrafish

Energy Technology Data Exchange (ETDEWEB)

Zheng, Jia-Lang, E-mail: zhengjialang@aliyun.com; Yuan, Shuang-Shuang; Wu, Chang-Wen; Lv, Zhen-Ming; Zhu, Ai-Yi

2017-01-15

Highlights: • Gene changed at mRNA, protein and activity levels between exposure time points. • ROS mediated antioxidant and inflammatory responses by Nrf2 and NF-κB. • The effect of time of day on Cd-induced toxicity should not be neglected in fish. - Abstract: Up to date, little information is available on effects of circadian rhythm on metal-induced toxicity in fish. In this study, zebrafish were acutely exposed to 0.97 mg L{sup −1} cadmium for 12 h either at ZT0 (the light intensity began to reached maximum) or at ZT12 (light intensity began to reached minimum) to evaluate the temporal sensitivity of oxidative stress and inflammatory responses in the brain of zebrafish. Profiles of responses of some genes at mRNA, protein and activity levels were different between ZT0 and ZT12 in the normal water. Exposure to Cd induced contrary antioxidant responses and similar inflammatory responses between ZT0 and ZT12. However, the number of inflammatory genes which were up-regulated was significantly greater at ZT12 than at ZT0. And, the up-regulated inflammatory genes were more responsive at ZT12 than at ZT0. At ZT12, antioxidant genes were down-regulated at mRNA, protein and activity levels. Contrarily, antioxidant genes were not affected at mRNA levels but activated at the protein and/or activity levels at ZT0. Reactive oxygen species (ROS) sharply increased and remained relatively stable when fish were exposed to Cd at ZT12 and ZT0, respectively. Positive correlations between ROS levels and mRNA levels of nuclear transcription factor κB (NF-κB) and between mRNA levels of NF-κB and its target genes were observed, suggesting that ROS may play an essential role in regulating the magnitude of inflammatory responses. Taken together, oxidative stress and immunotoxicity in the brain were more serious when fish were exposed to Cd in the evening than in the morning, highlighting the importance of circadian rhythm in Cd-induced neurotoxicity in fish.

Yields, Phenolic Profiles and Antioxidant Activities of Ziziphus jujube Mill. in Response to Different Fertilization Treatments

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Min Wang

2013-09-01

Full Text Available Increasing demand for more jujube (Ziziphus jujube Mill. production requires understanding the specific fertilization needs of jujube trees. This study was conducted to compare fruit yields, phenolic profiles and antioxidant activity of jujube in response to different fertilizers. Application of organic fertilizer appeared to enhance the phenolics and antioxidant activity accumulation of jujubes, compared to conventional fertilized jujubes. Amongst inorganic fertilizers, supplemental potassium as an individual nutrient improved the accumulation of phenolics in jujubes. Our results demonstrate that phenolics levels and antioxidant activity of jujube can be manipulated through fertilizer management and tracked by following proanthocyanidin concentrations. In a practical production context, the combination of organic fertilizers and inorganic fertilizers such as more supplemental individual potassium, and less supplemental individual nitrogen and phosphorus, might be the best management combination for achieving higher phenolic concentration, stronger antioxidant activity and a good harvest.

Renoprotective effects of antioxidants against cisplatin nephrotoxicity

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Hajian Shabnam

2014-04-01

Full Text Available Nephrotoxicity is the major limitation for the clinical use of cisplatin as an anti-tumoural drug. Intracellular effects of cisplatin cause tubular damage and tubular dysfunction with sodium, potassium, and magnesium wasting. Renoperotective strategies against cisplatin are classified on 8 targets: 1 Decrease of cisplatin uptake by renal cell, 2 Inhibition of cisplatin metabolism, 3 Blocking cell death pathways, 4 Cyclin-dependent kinase inhibitors, 5 Pharmacologic, molecular, and genetic blockade of p53, 6 Inhibition of specific Mitogen-activated protein kinase, 7 Antioxidants usage for renoprotection against cisplatin injury and inhibit of oxidative stress, 8 Suppress of inflammation. The oxidation reactions can produce free radicals, which start chain reactions and subsequently can cause a large number of diseases in humans. Antioxidant from natural products have attracted the physicians’ attentions, nowadays. The natural product antioxidants detoxify reactive oxygen species (ROS in kidneys, without affecting the anticancer efficacy of cisplatin. Hence, antioxidants have potential therapeutic applications.

The oxidative stress and antioxidant responses of Litopenaeus vannamei to low temperature and air exposure.

Science.gov (United States)

Xu, Zihan; Regenstein, Joe M; Xie, Dandan; Lu, Wenjing; Ren, Xingchen; Yuan, Jiajia; Mao, Linchun

2018-01-01

Low temperature and air exposure were the key attributes for waterless transportation of fish and shrimp. In order to investigate the oxidative stress and antioxidant responses of the live shrimp Litopenaeus vannamei in the mimic waterless transportation, live shrimp were cooled at 13 °C for 3 min, stored in oxygen at 15 °C for 12 h, and then revived in water at 25 °C. The survival rate of shrimp under this waterless transportation system was over 86.67%. The ultrastructure of hepatopancreas cells were observed while activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione peroxidase (GSH-Px), antisuperoxide anion free radicals (ASAFR), total antioxidant capacity (TAOC), reactive oxygen species (ROS) production, content of malondialdehyde (MDA) and relative mRNA expressions of CAT and GSH-Px in the hemolymph and hepatopancreas were determined. Slight distortions of some organelles in hepatopancreas cells was reversible upon the shrimp revived from the cold shock. The activities of SOD, POD, CAT, GSH-Px, TAOC, ROS production and relative mRNA expressions of CAT and GSH-Px increased following the cold shock and reached peak levels after 3 or 6 h of storage, and then decreased gradually. There was no significant difference between the fresh and the revived shrimp in SOD, POD, GSH-Px, TAOC, ROS, MDA and relative mRNA expressions of CAT and GSH-Px. The oxidative stress and antioxidant responses were tissue-specific because hepatopancreas seemed to have a greater ability to defend against organelle damage and was more sensitive to stress than hemolymph based on the results of SOD activity, MDA content and GSH-Px mRNA expression. These results revealed that low temperature and air exposure caused significant oxidative and antioxidant responses, but did not lead to irreversible damages in this waterless system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dietary antioxidants and exercise.

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

2004-01-01

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

Critical Role of Zinc as Either an Antioxidant or a Prooxidant in Cellular Systems

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Sung Ryul Lee

2018-01-01

Full Text Available Zinc is recognized as an essential trace metal required for human health; its deficiency is strongly associated with neuronal and immune system defects. Although zinc is a redox-inert metal, it functions as an antioxidant through the catalytic action of copper/zinc-superoxide dismutase, stabilization of membrane structure, protection of the protein sulfhydryl groups, and upregulation of the expression of metallothionein, which possesses a metal-binding capacity and also exhibits antioxidant functions. In addition, zinc suppresses anti-inflammatory responses that would otherwise augment oxidative stress. The actions of zinc are not straightforward owing to its numerous roles in biological systems. It has been shown that zinc deficiency and zinc excess cause cellular oxidative stress. To gain insights into the dual action of zinc, as either an antioxidant or a prooxidant, and the conditions under which each role is performed, the oxidative stresses that occur in zinc deficiency and zinc overload in conjunction with the intracellular regulation of free zinc are summarized. Additionally, the regulatory role of zinc in mitochondrial homeostasis and its impact on oxidative stress are briefly addressed.

Antioxidant response of soybean seedlings to joint stress of lanthanum and acid rain.

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Liang, Chanjuan; Wang, Weimin

2013-11-01

Excess of rare earth elements in soil can be a serious environmental stress on plants, in particular when acid rain coexists. To understand how such a stress affects plants, we studied antioxidant response of soybean leaves and roots exposed to lanthanum (0.06, 0.18, and 0.85 mmol L(-1)) under acid rain conditions (pH 4.5 and 3.0). We found that low concentration of La3+ (0.06 mmol L(-1)) did not affect the activity of antioxidant enzymes (catalase and peroxidase) whereas high concentration of La3+ (≥0.18 mmol L(-1)) did. Compared to treatment with acid rain (pH 4.5 and pH 3.0) or La3+ alone, joint stress of La3+ and acid rain affected more severely the activity of catalase and peroxidase, and induced more H2O2 accumulation and lipid peroxidation. When treated with high level of La3+ (0.85 mmol L(-1)) alone or with acid rain (pH 4.5 and 3.0), roots were more affected than leaves regarding the inhibition of antioxidant enzymes, physiological function, and growth. The severity of oxidative damage and inhibition of growth caused by the joint stress associated positively with La3+ concentration and soil acidity. These results will help us understand plant response to joint stress, recognize the adverse environmental impact of rare earth elements in acidic soil, and develop measures to eliminate damage caused by such joint stress.

Suppression of NRF2–ARE activity sensitizes chemotherapeutic agent-induced cytotoxicity in human acute monocytic leukemia cells

International Nuclear Information System (INIS)

Peng, Hui; Wang, Huihui; Xue, Peng; Hou, Yongyong; Dong, Jian; Zhou, Tong; Qu, Weidong; Peng, Shuangqing; Li, Jin; Carmichael, Paul L.; Nelson, Bud; Clewell, Rebecca; Zhang, Qiang; Andersen, Melvin E.; Pi, Jingbo

2016-01-01

Nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of the antioxidant response element (ARE)-dependent transcription, plays a pivotal role in chemical detoxification in normal and tumor cells. Consistent with previous findings that NRF2–ARE contributes to chemotherapeutic resistance of cancer cells, we found that stable knockdown of NRF2 by lentiviral shRNA in human acute monocytic leukemia (AML) THP-1 cells enhanced the cytotoxicity of several chemotherapeutic agents, including arsenic trioxide (As 2 O 3 ), etoposide and doxorubicin. Using an ARE-luciferase reporter expressed in several human and mouse cells, we identified a set of compounds, including isonicotinic acid amides, isoniazid and ethionamide, that inhibited NRF2–ARE activity. Treatment of THP-1 cells with ethionamide, for instance, significantly reduced mRNA expression of multiple ARE-driven genes under either basal or As 2 O 3 -challenged conditions. As determined by cell viability and cell cycle, suppression of NRF2–ARE by ethionamide also significantly enhanced susceptibility of THP-1 and U937 cells to As 2 O 3 -induced cytotoxicity. In THP-1 cells, the sensitizing effect of ethionamide on As 2 O 3 -induced cytotoxicity was highly dependent on NRF2. To our knowledge, the present study is the first to demonstrate that ethionamide suppresses NRF2–ARE signaling and disrupts the transcriptional network of the antioxidant response in AML cells, leading to sensitization to chemotherapeutic agents. - Highlights: • Identification of novel inhibitors of ARE-dependent transcription • Suppression of NRF2–ARE sensitizes THP-1 cells to chemotherapy. • Ethionamide suppresses ARE-dependent transcriptional activity. • Ethionamide and isoniazid increase the cytotoxicity of As 2 O 3 in AML cells. • Sensitization of THP-1 cells to As 2 O 3 toxicity by ethionamide is NRF2-dependent.

DDTs-induced antioxidant responses in plants and their influence on phytoremediation process.

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Mitton, Francesca M; Gonzalez, Mariana; Monserrat, José M; Miglioranza, Karina S B

2018-01-01

Phytoremediation is a low cost technology based on the use of plants to remove a wide range of pollutants from the environment, including the insecticide DDT. However, some pollutants are known to enhance generation of reactive oxygen species (ROS), which can generate toxic effects on plants affecting the phytoremediation efficiency. This study aims to analyze the potential use of antioxidant responses as a measure of tolerance to select plants for phytoremediation purposes. Tomato and zucchini plants were grown for 15 days in soils contaminated with DDTs (DDT + DDE + DDD). Protein content, glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx) and catalase (CAT) activities were measured in plant tissues. Exposure to DDTs did not affect protein content or CAT activity in any of the species. GST, GR and GPx activity showed different responses in exposed and control tomato plants. After DDTs exposure, tomato showed increased GR and GPX activity in stems and leaves, respectively, and a decrease in the GST activity in roots. As no effects were observed in zucchini, results suggest different susceptibility and/or defense mechanisms involved after pesticide exposure. Finally, both species differed also in terms of DDTs uptake and translocation. The knowledge about antioxidant responses induced by pesticides exposure could be helpful for planning phytoremediation strategies and for the selection of tolerant species according to particular scenarios. Copyright © 2017 Elsevier Inc. All rights reserved.

Caffeine and sleep-deprivation mediated changes in open-field behaviours, stress response and antioxidant status in mice

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Onaolapo, J. Olakunle; Onaolapo, Y. Adejoke; Akanmu, A. Moses; Olayiwola, Gbola

2016-01-01

Objectives: Effects of daily caffeine consumption on open-field behaviours, serum corticosterone and brain antioxidant levels were investigated after six hours of total sleep-deprivation in prepubertal mice. We tested the hypothesis that daily caffeine consumption may significantly alter behaviour, stress and antioxidative response of prepubertal mice to an acute episode of total sleep-deprivation. Methods: Prepubertal Swiss mice of both sexes were assigned to two main groups of 120 each (...

Differential responses of the antioxidant system of ametryn and clomazone tolerant bacteria.

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Leila Priscila Peters

Full Text Available The herbicides ametryn and clomazone are widely used in sugarcane cultivation, and following microbial degradation are considered as soil and water contaminants. The exposure of microorganisms to pesticides can result in oxidative damage due to an increase in the production of reactive oxygen species (ROS. This study investigated the response of the antioxidant systems of two bacterial strains tolerant to the herbicides ametryn and clomazone. Bacteria were isolated from soil with a long history of ametryn and clomazone application. Comparative analyses based on 16S rRNA gene sequences revealed that strain CC07 is phylogenetically related to Pseudomonas aeruginosa and strain 4C07 to P. fulva. The two bacterial strains were grown for 14 h in the presence of separate and combined herbicides. Lipid peroxidation, reduced glutathione content (GSH and antioxidant enzymes activities were evaluated. The overall results indicated that strain 4C07 formed an efficient mechanism to maintain the cellular redox balance by producing reactive oxygen species (ROS and subsequently scavenging ROS in the presence of the herbicides. The growth of bacterium strain 4C07 was inhibited in the presence of clomazone alone, or in combination with ametryn, but increased glutathione reductase (GR and glutathione S-transferase (GST activities, and a higher GSH concentration were detected. Meanwhile, reduced superoxide dismutase (SOD, catalase (CAT and GST activities and a lower concentration of GSH were detected in the bacterium strain CC07, which was able to achieve better growth in the presence of the herbicides. The results suggest that the two bacterial strains tolerate the ametryn and clomazone herbicides with distinctly different responses of the antioxidant systems.

Differential Responses of the Antioxidant System of Ametryn and Clomazone Tolerant Bacteria

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Peters, Leila Priscila; Carvalho, Giselle; Martins, Paula Fabiane; Dourado, Manuella Nóbrega; Vilhena, Milca Bartz; Pileggi, Marcos; Azevedo, Ricardo Antunes

2014-01-01

The herbicides ametryn and clomazone are widely used in sugarcane cultivation, and following microbial degradation are considered as soil and water contaminants. The exposure of microorganisms to pesticides can result in oxidative damage due to an increase in the production of reactive oxygen species (ROS). This study investigated the response of the antioxidant systems of two bacterial strains tolerant to the herbicides ametryn and clomazone. Bacteria were isolated from soil with a long history of ametryn and clomazone application. Comparative analyses based on 16S rRNA gene sequences revealed that strain CC07 is phylogenetically related to Pseudomonas aeruginosa and strain 4C07 to P. fulva. The two bacterial strains were grown for 14 h in the presence of separate and combined herbicides. Lipid peroxidation, reduced glutathione content (GSH) and antioxidant enzymes activities were evaluated. The overall results indicated that strain 4C07 formed an efficient mechanism to maintain the cellular redox balance by producing reactive oxygen species (ROS) and subsequently scavenging ROS in the presence of the herbicides. The growth of bacterium strain 4C07 was inhibited in the presence of clomazone alone, or in combination with ametryn, but increased glutathione reductase (GR) and glutathione S-transferase (GST) activities, and a higher GSH concentration were detected. Meanwhile, reduced superoxide dismutase (SOD), catalase (CAT) and GST activities and a lower concentration of GSH were detected in the bacterium strain CC07, which was able to achieve better growth in the presence of the herbicides. The results suggest that the two bacterial strains tolerate the ametryn and clomazone herbicides with distinctly different responses of the antioxidant systems. PMID:25380132

Effects of Puerariae Radix extract on the activity of antioxidant

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Young-Joon Eun; Ki Rok Kwon; Tae Jin Rhim; Yun-Kyung Song; Hyung-Ho Lim

2007-01-01

Objective : The objective of this study was to investigate the antioxidative effects of Puerariae Radix extract. Method : Total antioxidant capacity (TAC), Total antioxidant response (TAR), Total phenolic content, Reactive oxygen species (ROS), 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities, lipid peroxidation were examined. Result : Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free r...

Allergen immunotherapy induces a suppressive memory response mediated by IL-10 in a mouse asthma model

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Vissers, Joost L. M.; van Esch, Betty C. A. M.; Hofman, Gerard A.; Kapsenberg, Martien L.; Weller, Frank R.; van Oosterhout, Antoon J. M.

2004-01-01

Background: Human studies have demonstrated that allergen immunotherapy induces memory suppressive responses and IL-10 production by allergen-specific T cells. Previously, we established a mouse model in which allergen immunotherapy was effective in the suppression of allergen-induced asthma

Assessing the Role of ETHYLENE RESPONSE FACTOR Transcriptional Repressors in Salicylic Acid-Mediated Suppression of Jasmonic Acid-Responsive Genes.

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Caarls, Lotte; Van der Does, Dieuwertje; Hickman, Richard; Jansen, Wouter; Verk, Marcel C Van; Proietti, Silvia; Lorenzo, Oscar; Solano, Roberto; Pieterse, Corné M J; Van Wees, Saskia C M

2017-02-01

Salicylic acid (SA) and jasmonic acid (JA) cross-communicate in the plant immune signaling network to finely regulate induced defenses. In Arabidopsis, SA antagonizes many JA-responsive genes, partly by targeting the ETHYLENE RESPONSE FACTOR (ERF)-type transcriptional activator ORA59. Members of the ERF transcription factor family typically bind to GCC-box motifs in the promoters of JA- and ethylene-responsive genes, thereby positively or negatively regulating their expression. The GCC-box motif is sufficient for SA-mediated suppression of JA-responsive gene expression. Here, we investigated whether SA-induced ERF-type transcriptional repressors, which may compete with JA-induced ERF-type activators for binding at the GCC-box, play a role in SA/JA antagonism. We selected ERFs that are transcriptionally induced by SA and/or possess an EAR transcriptional repressor motif. Several of the 16 ERFs tested suppressed JA-dependent gene expression, as revealed by enhanced JA-induced PDF1.2 or VSP2 expression levels in the corresponding erf mutants, while others were involved in activation of these genes. However, SA could antagonize JA-induced PDF1.2 or VSP2 in all erf mutants, suggesting that the tested ERF transcriptional repressors are not required for SA/JA cross-talk. Moreover, a mutant in the co-repressor TOPLESS, that showed reduction in repression of JA signaling, still displayed SA-mediated antagonism of PDF1.2 and VSP2. Collectively, these results suggest that SA-regulated ERF transcriptional repressors are not essential for antagonism of JA-responsive gene expression by SA. We further show that de novo SA-induced protein synthesis is required for suppression of JA-induced PDF1.2, pointing to SA-stimulated production of an as yet unknown protein that suppresses JA-induced transcription. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Garlic Sulfur Compounds Suppress Cancerogenesis and Oxidative Stress: a Review

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Dvořáková M.

2015-06-01

Full Text Available Garlic has long been considered a food with many health benefits. Several studies have confirmed that sulfur compounds are responsible for the positive effects of garlic on organisms. Garlic acts as an antioxidant by increasing antioxidant enzyme activity, reducing reactive oxygen species generation, and protecting proteins and lipids from oxidation. Garlic suppresses carcinogenesis through several mechanisms: (1 it reduces oxidative stress, and therefore, prevents damage to DNA; (2 it induces apoptosis or cell cycle arrest in cancer cells; and (3 it modifies gene expression through histon acetylation. The positive effects of garlic could be mediated by several mechanisms. It influences signalling pathways of gasotransmitters such as hydrogen sulfide. Garlic enhances hydrogen sulfide production both through its direct release and through an increase in activity of enzymes which produce hydrogen sulfide. Hydrogen sulfide acts as a signalling molecule in various tissues and participates in the regulation of many physiological processes. We can presume that garlic, which is able to release hydrogen sulfide, exhibits effects similar to those of this gasotransmitter.

Optimization of Ultrasonic-Assisted Extraction of Flavonoid Compounds and Antioxidants from Alfalfa Using Response Surface Method.

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Jing, Chang-Liang; Dong, Xiao-Fang; Tong, Jian-Ming

2015-08-26

Ultrasonic-assisted extraction (UAE) was used to extract flavonoid-enriched antioxidants from alfalfa aerial part. Response surface methodology (RSM), based on a four-factor, five-level central composite design (CCD), was employed to obtain the optimal extraction parameters, in which the flavonoid content was maximum and the antioxidant activity of the extracts was strongest. Radical scavenging capacity of the extracts, which represents the amounts of antioxidants in alfalfa, was determined by using 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) methods. The results showed good fit with the proposed models for the total flavonoid extraction (R² = 0.9849), for the antioxidant extraction assayed by ABTS method (R² = 0.9764), and by DPPH method (R² = 0.9806). Optimized extraction conditions for total flavonoids was a ratio of liquid to solid of 57.16 mL/g, 62.33 °C, 57.08 min, and 52.14% ethanol. The optimal extraction parameters of extracts for the highest antioxidant activity by DPPH method was a ratio of liquid to solid 60.3 mL/g, 54.56 °C, 45.59 min, and 46.67% ethanol, and by ABTS assay was a ratio of liquid to solid 47.29 mL/g, 63.73 °C, 51.62 min, and 60% ethanol concentration. Our work offers optimal extraction conditions for total flavonoids and antioxidants from alfalfa.

Short term supplementation of dietary antioxidants selectively regulates the inflammatory responses during early cutaneous wound healing in diabetic mice

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Park Na-Young

2011-11-01

Full Text Available Abstract Background Diabetic foot ulcers are serious complications for diabetic patients, yet the precise mechanism that underlines the treatment of these diabetic complications remains unclear. We hypothesized that dietary antioxidant supplementation with vitamin C, combined either with vitamin E or with vitamin E and NAC, improves delayed wound healing through modulation of blood glucose levels, oxidative stress, and inflammatory response. Methods Diabetes was induced by administration of alloxan monohydrate. Mice were divided into 4 groups; CON (non-diabetic control mice fed AIN 93 G purified rodent diet, DM (diabetic mice fed AIN 93 G purified rodent diet, VCE (diabetic mice fed 0.5% vitamin C and 0.5% vitamin E supplemented diet, and Comb (diabetic mice fed 0.5% vitamin C, 0.5% vitamin E, and 2.5% NAC supplemented diet. After 10 days of dietary antioxidant supplementation, cutaneous full-thickness excisional wounds were performed, and the rate of wound closure was examined. TBARS as lipid peroxidation products and vitamin E levels were measured in the liver. Expression levels of oxidative stress and inflammatory response related proteins were measured in the cutaneous wound site. Results Dietary antioxidant supplementation improved blood glucose levels and wound closure rate and increased liver vitamin E, but not liver TBARS levels in the diabetic mice as compared to those of the CON. In addition, dietary antioxidant supplementation modulated the expression levels of pIκBα, HO-1, CuZnSOD, iNOS and COX-2 proteins in the diabetic mice. Conclusions These findings demonstrated that delayed wound healing is associated with an inflammatory response induced by hyperglycaemia, and suggests that dietary antioxidant supplementation may have beneficial effects on wound healing through selective modulation of blood glucose levels, oxidative stress, and inflammatory response.

Modulation of keratinocyte expression of antioxidants by 4-hydroxynonenal, a lipid peroxidation end product

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Zheng, Ruijin [Pharmacology and Toxicology and Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Heck, Diane E. [Environmental Health Science, New York Medical College, Valhalla, NY (United States); Mishin, Vladimir; Black, Adrienne T. [Pharmacology and Toxicology and Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Shakarjian, Michael P. [Environmental Health Science, New York Medical College, Valhalla, NY (United States); Kong, Ah-Ng Tony; Laskin, Debra L. [Pharmacology and Toxicology and Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Laskin, Jeffrey D., E-mail: jlaskin@eohsi.rutgers.edu [Environmental and Occupational Medicine, Rutgers University-Robert Wood Johnson Medical School, Piscataway, NJ (United States)

2014-03-01

4-Hydroxynonenal (4-HNE) is a lipid peroxidation end product generated in response to oxidative stress in the skin. Keratinocytes contain an array of antioxidant enzymes which protect against oxidative stress. In these studies, we characterized 4-HNE-induced changes in antioxidant expression in mouse keratinocytes. Treatment of primary mouse keratinocytes and PAM 212 keratinocytes with 4-HNE increased mRNA expression for heme oxygenase-1 (HO-1), catalase, NADPH:quinone oxidoreductase (NQO1) and glutathione S-transferase (GST) A1-2, GSTA3 and GSTA4. In both cell types, HO-1 was the most sensitive, increasing 86–98 fold within 6 h. Further characterization of the effects of 4-HNE on HO-1 demonstrated concentration- and time-dependent increases in mRNA and protein expression which were maximum after 6 h with 30 μM. 4-HNE stimulated keratinocyte Erk1/2, JNK and p38 MAP kinases, as well as PI3 kinase. Inhibition of these enzymes suppressed 4-HNE-induced HO-1 mRNA and protein expression. 4-HNE also activated Nrf2 by inducing its translocation to the nucleus. 4-HNE was markedly less effective in inducing HO-1 mRNA and protein in keratinocytes from Nrf2 −/− mice, when compared to wild type mice, indicating that Nrf2 also regulates 4-HNE-induced signaling. Western blot analysis of caveolar membrane fractions isolated by sucrose density centrifugation demonstrated that 4-HNE-induced HO-1 is localized in keratinocyte caveolae. Treatment of the cells with methyl-β-cyclodextrin, which disrupts caveolar structure, suppressed 4-HNE-induced HO-1. These findings indicate that 4-HNE modulates expression of antioxidant enzymes in keratinocytes, and that this can occur by different mechanisms. Changes in expression of keratinocyte antioxidants may be important in protecting the skin from oxidative stress. - Highlights: • Lipid peroxidation generates 4-hydroxynonenal, a reactive aldehyde. • 4-HNE induces antioxidant proteins in mouse keratinocytes. • Induction of

Ultrasonic extraction of antioxidants from Chinese sumac (Rhus typhina L.) fruit using response surface methodology and their characterization.

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Lai, Jixiang; Wang, Huifang; Wang, Donghui; Fang, Fang; Wang, Fengzhong; Wu, Tao

2014-06-27

For the first time, response surface methodology (RSM) using a Box-Behnken Design (BBD) was employed to optimize the conditions for ultrasonic assisted extraction (UAE) of antioxidants from Chinese sumac (Rhus typhina L.) fruits. Initially, influencing factors such as liquid-solid ratio, duration of ultrasonic assisted extraction, pH range, extraction temperature and ethanol concentration were identified using single-factor experiments. Then, with respect to the three most significant influencing factors, the extraction process focusing on the DPPH· scavenging capacity of antioxidants was optimized using RSM. Results showed that the optimal conditions for antioxidant extraction were 13.03:1 (mL/g) liquid-solid ratio, 16.86 min extraction time and 40.51% (v/v) ethanol, and the desirability was 0.681. The UPLC-ESI-MS analysis results revealed eleven kinds of phenolic compounds, including four major rare anthocyanins, among the antioxidants. All these results suggest that UAE is efficient at extracting antioxidants and has the potential to be used in industry for this purpose.

ANTIOXIDANT SUPPLEMENTATION AND NASAL INFLAMMATORY RESPONSES AMONG YOUNG ASTHMATICS EXPOSED TO HIGH LEVELS OF OZONE

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Background: Recent studies examining the inflammatory response in atopic asthma to ozone suggest a release of soluble mediators of inflammation factors that might be related to reactive oxygen species (ROS). Antioxidant could prove useful in subjects exposed to additional oxidati...

Interocular suppression in strabismic amblyopia results in an attenuated and delayed hemodynamic response function in early visual cortex.

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Farivar, Reza; Thompson, Benjamin; Mansouri, Behzad; Hess, Robert F

2011-12-20

Factors such as strabismus or anisometropia during infancy can disrupt normal visual development and result in amblyopia, characterized by reduced visual function in an otherwise healthy eye and often associated with persistent suppression of inputs from the amblyopic eye by those from the dominant eye. It has become evident from fMRI studies that the cortical response to stimulation of the amblyopic eye is also affected. We were interested to compare the hemodynamic response function (HRF) of early visual cortex to amblyopic vs. dominant eye stimulation. In the first experiment, we found that stimulation of the amblyopic eye resulted in a signal that was both attenuated and delayed in its time to peak. We postulated that this delay may be due to suppressive effects of the dominant eye and, in our second experiment, measured the cortical response of amblyopic eye stimulation under two conditions--where the dominant eye was open and seeing a static pattern (high suppression) or where the dominant eye was patched and closed (low suppression). We found that the HRF in response to amblyopic eye stimulation depended on whether the dominant eye was open. This effect was manifested as both a delayed HRF under the suppressed condition and an amplitude reduction.

Antioxidative responses to arsenic in the arsenic-hyperaccumulator Chinese brake fern (Pteris vittata L.)

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Cao Xinde; Ma, Lena Q.; Tu Cong

2004-01-01

This study measured antioxidative responses of Chinese brake fern (Pteris vittata L.) upon exposure to arsenic (As) of different concentrations. Chinese brake fern was grown in an artificially-contaminated soil containing 0 to 200 mg As kg -1 (Na 2 HAsO 4 ) for 12 weeks in a greenhouse. Soil As concentrations at ≤20 mg kg -1 enhanced plant growth, with 12-71% biomass increase compared to the control. Such beneficial effects were not observed at >20 mg As kg -1 . Plant As concentrations increased with soil As concentrations, with more As being accumulated in the fronds (aboveground biomass) than in the roots and with maximum frond As concentration being 4675 mg kg -1 . Arsenic uptake by Chinese brake enhanced uptake of nutrient elements K, P, Fe, Mn, and Zn except Ca and Mg, whose concentrations mostly decreased. The contents of non-enzymatic antioxidants (glutathione, acid-soluble thiol) followed similar trends as plant As concentrations, increasing with soil As concentrations, with greater contents in the fronds than in the roots especially when exposed to high As concentrations (>50 mg kg -1 ). The activities of enzymatic antioxidants (superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase) in Chinese brake followed the same trends as plant biomass, increasing with soil As up to 20 mg kg -1 and then decreased. The results indicated though both enzymatic and non-enzymatic antioxidants played significant roles in As detoxification and hyperaccumulation in Chinese brake, the former is more important at low As exposure (≤20 mg kg -1 ), whereas the latter is more critical at high As exposure (50-200 mg kg -1 ). - At low levels of arsenic exposure, enzymatic antioxidants are important for arsenic detoxification and accumulation in Chinese brake fern, while non-enzymatic antioxidants were more important at high arsenic exposure

Oxidative stress and metabolic syndrome: Effects of a natural antioxidants enriched diet on insulin resistance.

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Mancini, Antonio; Martorana, Giuseppe Ettore; Magini, Marinella; Festa, Roberto; Raimondo, Sebastiano; Silvestrini, Andrea; Nicolotti, Nicola; Mordente, Alvaro; Mele, Maria Cristina; Miggiano, Giacinto Abele Donato; Meucci, Elisabetta

2015-04-01

Oxidative stress (OS) could play a role in metabolic syndrome-related manifestations contributing to insulin resistance (IR). The aim of the present study was to gain insight the relationships between OS, IR and other hormones involved in caloric balance, explaining the effects of a natural antioxidant-enriched diet in patients affected by metabolic syndrome. We investigated the effects of dietary antioxidants on IR, studying 53 obese (20 males and 33 females, 18-66 years old, BMI 36.3 ± 5.5 kg/m 2 ), with IR evaluated by Homeostasis Model Assessment (HOMA)-index, comparing 4 treatments: hypocaloric diet alone (group A) or plus metformin 1000 mg/daily (group B), natural antioxidants-enriched hypocaloric diet alone (group C) or plus metformin (group D). A personalized program, with calculated antioxidant intake of 800-1000 mg/daily, from fruit and vegetables, was administered to group C and D. The glycemic and insulinemic response to oral glucose load, and concentrations of total-, LDL- and HDL-cholesterol, triglycerides, uric acid, C reactive protein, fT3, fT4, TSH, insulin-like growth factor 1 were evaluated before and after 3-months. Plasma Total antioxidant capacity was determined by H 2 O 2 -metmyoglobin system, which interacting with the chromogen ABTS generates a radical with latency time (LAG) proportional to antioxidant content. Despite a similar BMI decrease, we found a significant decrease of HOMA and insulin peak only in group B and D. Insulin response (AUC) showed the greatest decrease in group D (25.60  ±  8.96%) and was significantly lower in group D vs B. No differences were observed in glucose response, lipid metabolism and TAC (expressed as LAG values). TSH values were significantly suppressed in group D vs B. These data suggest that dietary antioxidants ameliorate insulin-sensitivity in obese subjects with IR by enhancing the effect of insulin-sensitizing drugs albeit with molecular mechanisms which remain yet to be elucidated

Optimization of Ultrasound-Assisted Extraction of Antioxidants from Apium graveolens L. Seeds using Response Surface Methodology

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Şule Dinç Zor

2017-09-01

Full Text Available In this study, optimum conditions for ultrasound-assisted extraction (UAE of antioxidants from Apium graveolens L. seeds were investigated by Response Surface Methodology (RSM. A Box-Behnken Design (BBD was used to evaluate the effect of sonication time (5, 10, 15 min, ultrasound power (60, 120, 180 W and the ratio of extraction solvent in terms of methanol (0, 50, 100% on antioxidant capacity. The optimal UAE conditions for the parameters investigated were 11 min of sonication time, ultrasound power of 131 W and 100% methanol as an extraction solvent. Under these conditions, UAE of antioxidants from the seeds achieved a maximum of 95.08% in respect to 1,1-diphenyl-2-picryl hydrazyl (DPPH radical scavenging activity. Additionally, the high value of the adjusted coefficient of determination (R2adj = 0.9192 and the non-significant difference between experimental and predicted values confirmed the validity of the quadratic polynomial model. Hence, UAE is a suitable, fast, economical and practical technique for the extraction of antioxidants from Apium graveolens L. seeds.

Suppression of pro-inflammatory T-cell responses by human mesothelial cells.

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Lin, Chan-Yu; Kift-Morgan, Ann; Moser, Bernhard; Topley, Nicholas; Eberl, Matthias

2013-07-01

Human γδ T cells reactive to the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP) contribute to acute inflammatory responses. We have previously shown that peritoneal dialysis (PD)-associated infections with HMB-PP producing bacteria are characterized by locally elevated γδ T-cell frequencies and poorer clinical outcome compared with HMB-PP negative infections, implying that γδ T cells may be of diagnostic, prognostic and therapeutic value in acute disease. The regulation by local tissue cells of these potentially detrimental γδ T-cell responses remains to be investigated. Freshly isolated γδ or αβ T cells were cultured with primary mesothelial cells derived from omental tissue, or with mesothelial cell-conditioned medium. Stimulation of cytokine production and proliferation by peripheral T cells in response to HMB-PP or CD3/CD28 beads was assessed by flow cytometry. Resting mesothelial cells were potent suppressors of pro-inflammatory γδ T cells as well as CD4+ and CD8+ αβ T cells. The suppression of γδ T-cell responses was mediated through soluble factors released by primary mesothelial cells and could be counteracted by SB-431542, a selective inhibitor of TGF-β and activin signalling. Recombinant TGF-β1 but not activin-A mimicked the mesothelial cell-mediated suppression of γδ T-cell responses to HMB-PP. The present findings indicate an important regulatory function of mesothelial cells in the peritoneal cavity by dampening pro-inflammatory T-cell responses, which may help preserve the tissue integrity of the peritoneal membrane in the steady state and possibly during the resolution of acute inflammation.

Acute phase response and plasma carotenoid concentrations in older women: findings from the nun study.

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Boosalis, M G; Snowdon, D A; Tully, C L; Gross, M D

1996-01-01

This cross-sectional study investigated whether the acute phase response was associated with suppressed circulating levels of antioxidants in a population of 85 Catholic sisters (nuns) ages 77-99 y. Fasting blood was drawn to determine the presence of an acute phase response, as defined by an elevation in the serum concentration of C-reactive protein. Serum concentrations of albumin, thyroxine-binding prealbumin, zinc, copper, and fibrinogen were determined as were plasma concentrations of carotenoids and alpha tocopherol. Results showed that the presence of an acute phase response was associated with (1) an expected significant decrease in the serum concentrations of albumin (p < 0.001) and thyroxine-binding prealbumin (p < 0.001); (2) an expected significant increase in copper (p < 0.001) and fibrinogen (p = 0.003); and (3) a significant decrease in the plasma concentrations of lycopene (p = 0.03), alpha carotene (p = 0.02), beta carotene (p = 0.02), and total carotenoids (p = 0.01). The acute phase response was associated with decreased plasma levels of the antioxidants lycopene, alpha carotene, and beta carotene. This decrease in circulating antioxidants may further compromise antioxidant status and increase oxidative stress and damage in elders.

Optimization of ultrasonic-assisted extraction of phenolic antioxidants from Malus baccata (Linn.) Borkh. using response surface methodology.

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Wang, Lu; Wang, Zhenyu; Li, Xiaoyu

2013-05-01

In this study, the optimum extraction conditions for maximum recovery of the content of total phenolics (TPC) and total antioxidant abilities were analyzed for Malus baccata (Linn.) Borkh. using response surface methodology. The effects of ethanol percentage (X1 ,%), ultrasonic power (X2 , W) and extraction temperature (X3 , °C) on the total phenolic content (Y1 ) and antioxidant ability (Y2 ) were evaluated. A second-order polynomial model produced a satisfactory fitting of the experimental data with regard to total phenolic content (R(2) = 0.9942, P antioxidant ability (R(2) = 0.9966, P extraction temperature of 51.1°C for TPC and 60.5%, 311.4 W, 51.6°C for antioxidant ability, the predicted values agreed well with the experimental values. Results implied that the major phenolic compounds in obtained extracts as chlorogenic acid, quercetin-3-gal/glu, quercetin-3-xyl/ara, phloretin-2-xyloside, quercetin-3- rhamnoside, and phloridzin. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Optimization of Ultrasonic-Assisted Extraction of Flavonoid Compounds and Antioxidants from Alfalfa Using Response Surface Method

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Chang-Liang Jing

2015-08-01

Full Text Available Ultrasonic-assisted extraction (UAE was used to extract flavonoid-enriched antioxidants from alfalfa aerial part. Response surface methodology (RSM, based on a four-factor, five-level central composite design (CCD, was employed to obtain the optimal extraction parameters, in which the flavonoid content was maximum and the antioxidant activity of the extracts was strongest. Radical scavenging capacity of the extracts, which represents the amounts of antioxidants in alfalfa, was determined by using 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid (ABTS and 2,2′-diphenyl-1-picrylhydrazyl (DPPH methods. The results showed good fit with the proposed models for the total flavonoid extraction (R2 = 0.9849, for the antioxidant extraction assayed by ABTS method (R2 = 0.9764, and by DPPH method (R2 = 0.9806. Optimized extraction conditions for total flavonoids was a ratio of liquid to solid of 57.16 mL/g, 62.33 °C, 57.08 min, and 52.14% ethanol. The optimal extraction parameters of extracts for the highest antioxidant activity by DPPH method was a ratio of liquid to solid 60.3 mL/g, 54.56 °C, 45.59 min, and 46.67% ethanol, and by ABTS assay was a ratio of liquid to solid 47.29 mL/g, 63.73 °C, 51.62 min, and 60% ethanol concentration. Our work offers optimal extraction conditions for total flavonoids and antioxidants from alfalfa.

Antioxidant mechanisms of iso-6-cassine in suppressing seizures induced by pilocarpine

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Rivelilson Mendes de Freitas

2011-06-01

Full Text Available The aim of this study was to evaluate the in vitro antioxidant effects of 12-[(2R,5R,6R-5-hydroxy-6-methylpiperidin-2-yl]dodecan-2-one (iso-6-cassine; ISO and the anticonvulsant effects of ISO on pilocarpine-induced seizures in rats. Wistar rats were treated with 0.9% saline (i.p., control group, pilocarpine (400 mg/kg, i.p., pilocarpine group, and the association of ISO (1.0 mg/kg, i.p. plus pilocarpine (400 mg/kg, i.p., 30 min after administration of ISO (ISO plus pilocarpine group. After the treatments all groups were observed for 1h. The antioxidant effect of ISO on the pilocarpine model was assessed by determining the activity of glutathione peroxidase (GPx, glutathione-S-transferase (GST and catalase (CAT as well as the levels of reactive species (RS and lipid peroxidation (LP. In vitro, ISO (5 μM reduced RS and LP. ISO (1.0 mg/kg and abolished seizures and death induced by pilocarpine in rats. ISO protected against the increase in the RS and LP levels, GST activity as well as the inhibition of GPx activity caused by pilocarpine. In addition, ISO increased the catalase activity in hippocampus of seized rats. In conclusion, the dta suggest that ISO can present anticonvulsant and antioxidant properties in the pilocarpine model of seizures in rats.

Modulation of the antioxidative response of Spartina densiflora against iron exposure.

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Martínez Domínguez, David; Torronteras Santiago, Rafael; Córdoba García, Francisco

2009-06-01

Spartina densiflora, an invader cordgrass living in polluted salt marshes of the Odiel estuary (SW Spain), was collected and cultured under controlled laboratory conditions. After acclimation to non-polluted soils for 28 days, both metabolites and enzymes activities used as indicators of oxidative stress were reduced significantly. Then, plants were exposed to 500 and 1000 ppm Fe-ethylenediamine-N,N'-2-hydroxyphenyl acetic acid (EDDHA) for 28 days. Our data demonstrate that iron content in leaves was enhanced by iron exposure. This iron increase caused an enhancement in the concentration of H2O2, hydroperoxides and lipid peroxidation, and a decrease in chlorophyll levels. Thus, iron exposure led to oxidative stress conditions. However, oxidative indicators stabilised after first 2 weeks of exposure, although the highest iron levels in leaves were reached at the end of treatments. Iron exposure induced an enhancement of catalase, ascorbate peroxidase and guaiacol peroxidase activities, together with an increase in total and oxidised ascorbate. This response may be defensive against oxidative stress and thus help to explain why cell oxidative damages were stabilised. Thus, by using a sensitive long-time protocol, iron-dependent oxidative damages may be controlled and even reverted successfully by the activation of the antioxidative defences of S. densiflora. This efficient antioxidative system, rapidly modulated in response to excess iron and other environmental stressors, may account for S. densiflora's successful adaptation to stress conditions in its habitat.

Functional-drink rich in antioxidant cardamom-rhizome (Amomum cardamomum willd) suppresses inflammation and improves lipid profile

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Winarsi, H.; Susilowati, S. S.

2018-01-01

The aim of this research was to know the effect of functional drink rich in antioxidant cardamom rhizome (Fd-Carrhi) on level of IL-6, C-RP, and lipid profile of atherosclerotic. A total of 30 women with atherosclerosis, age 40-65 years old, hypertension, hypercholesterolemia, hypertriglyceridemia, lived in Purwokerto, Banyumas, Central Java, Indonesia, and were willing to sign informed consent, recruited as research subjects. They consumed simvastatin from doctors, divided by 3 groups of 10 people each. Group I, given Fd-Carrhi; II, placebo; and III, only simvastatin, for 2 months. As many as 100 ml of Fd-Carrhi or placebo were given every morning. Blood samples were taken 3 times, 1 ml, at baseline, 1 and 2 months after intervention. Blood plasma was determined levels of IL-6, C-RP, as well as total cholesterol (total-c), triglycerides (TG), LDL-c, and HDL-c. Result showed Fd-Carrhi versus placebo significantly decreased plasma level of IL-6, C-RP, total-c, and LDL-c, and otherwise increased HDL-c, but no differences were seen in TG. The findings clearly support Fd-Carrhi inhibit the development of atherosclerosis towards cardiovascular heart diseases (CHD) by suppressing IL-6 and CRP levels, and improving lipid profile.

Ultrasonic Extraction of Antioxidants from Chinese Sumac (Rhus typhina L. Fruit Using Response Surface Methodology and Their Characterization

Directory of Open Access Journals (Sweden)

Jixiang Lai

2014-06-01

Full Text Available For the first time, response surface methodology (RSM using a Box-Behnken Design (BBD was employed to optimize the conditions for ultrasonic assisted extraction (UAE of antioxidants from Chinese sumac (Rhus typhina L. fruits. Initially, influencing factors such as liquid-solid ratio, duration of ultrasonic assisted extraction, pH range, extraction temperature and ethanol concentration were identified using single-factor experiments. Then, with respect to the three most significant influencing factors, the extraction process focusing on the DPPH· scavenging capacity of antioxidants was optimized using RSM. Results showed that the optimal conditions for antioxidant extraction were 13.03:1 (mL/g liquid-solid ratio, 16.86 min extraction time and 40.51% (v/v ethanol, and the desirability was 0.681. The UPLC-ESI-MS analysis results revealed eleven kinds of phenolic compounds, including four major rare anthocyanins, among the antioxidants. All these results suggest that UAE is efficient at extracting antioxidants and has the potential to be used in industry for this purpose.

Optimisation of Ultrasound-Assisted Extraction Conditions for Phenolic Content and Antioxidant Capacity from Euphorbia tirucalli Using Response Surface Methodology

Science.gov (United States)

Vuong, Quan V.; Goldsmith, Chloe D.; Dang, Trung Thanh; Nguyen, Van Tang; Bhuyan, Deep Jyoti; Sadeqzadeh, Elham; Scarlett, Christopher J.; Bowyer, Michael C.

2014-01-01

Euphorbia tirucalli (E. tirucalli) is now widely distributed around the world and is well known as a source of traditional medicine in many countries. This study aimed to utilise response surface methodology (RSM) to optimise ultrasonic-assisted extraction (UAE) conditions for total phenolic compounds (TPC) and antioxidant capacity from E. tirucalli leaf. The results showed that ultrasonic temperature, time and power effected TPC and antioxidant capacity; however, the effects varied. Ultrasonic power had the strongest influence on TPC; whereas ultrasonic temperature had the greatest impact on antioxidant capacity. Ultrasonic time had the least impact on both TPC and antioxidant capacity. The optimum UAE conditions were determined to be 50 °C, 90 min. and 200 W. Under these conditions, the E. tirucalli leaf extract yielded 2.93 mg GAE/g FW of TPC and exhibited potent antioxidant capacity. These conditions can be utilised for further isolation and purification of phenolic compounds from E. tirucalli leaf. PMID:26785074

Antioxidative stress responses in the floating macrophyte Lemna minor L. with cylindrospermopsin exposure.

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Flores-Rojas, Nelida Cecilia; Esterhuizen-Londt, Maranda; Pflugmacher, Stephan

2015-12-01

Cylindrospermopsin toxicity and oxidative stress have been examined in aquatic animals, however, only a few studies with aquatic plants have been conducted focusing on the potential for bioaccumulation of cylindrospermopsin. The oxidative stress effects caused by cylindrospermopsin on macrophytes have not yet been specifically studied. The oxidative stress response of Lemna minor L. with exposure to cylindrospermopsin, was therefore tested in this study. The hydrogen peroxide concentration together with the activities of the antioxidant enzymes (catalase, peroxidase, glutathione reductase and glutathione S-transferase) were determined after 24h (hours) of exposure to varying concentrations (0.025, 0.25, 2.5 and 25μg/L) of cylindrospermopsin. Responses with longer exposure periods (48, 96, 168h) were tested only with exposure to 2.5 and 25μg/L cylindrospermopsin. Additionally, the content of the carotenoids was determined as a possible non-enzymatic antioxidant defence mechanism against cylindrospermopsin. The levels of hydrogen peroxide increased after 24h even at the lowest cylindrospermopsin exposure concentrations. Catalase showed the most representative antioxidant response observed after 24h and maintained its activity throughout the experiment. Catalase activity corresponded with the contents of hydrogen peroxide at 2.5 and 25μg/L cylindrospermopsin. The data suggest that glutathione S-transferase, glutathione reductase and the carotenoid content act together with catalase but are more sensitive to higher concentrations of cylindrospermopsin and after a longer exposure period (168h). The results indicate that cylindrospermopsin promotes oxidative stress in L. minor at concentrations of 2.5 and 25μg/L. However, L. minor has sufficient defence mechanisms in place against this cyanobacterial toxin. Even though L. minor exhibits the potential to managing and control cylindrospermopsin contamination in aquatic systems, further studies in tolerance limits to

Responses of Phospholipase D and Antioxidant System to Mechanical Wounding in Postharvest Banana Fruits

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Li Li

2017-01-01

Full Text Available Banana fruits are susceptible to mechanical damage. The present study was to investigate the responses of phospholipase D (PLD and antioxidant system to mechanical wounding in postharvest banana fruits. During 16 d storage at 25°C and 90% relative humidity, PLD activity in wounded fruits was significantly higher than that in control (without artificial wounding fruits. The higher value of PLD mRNA was found in wounded fruits than in control. PLD mRNA expression reached the highest peak on day 4 in both groups, but it was 2.67 times in wounded fruits compared to control at that time, indicating that PLD gene expression was activated in response to wounding stress. In response to wounding stress, the higher lipoxygenase (LOX activity was observed and malondialdehyde (MDA production was accelerated. The activities of antioxidant enzymes such as superoxide dismutase (SOD, catalase (CAT, peroxidase (POD, and ascorbate peroxidase (APX in wounded fruits were significantly higher than those in control. The concentrations of reactive oxygen species (ROS such as superoxide anion (O2•- and hydrogen peroxide (H2O2 in fruits increased under mechanical wounding. The above results provided a basis for further investigating the mechanism of postharvest banana fruits adapting to environmental stress.

Antioxidant Capacity of Beetroot: Traditional vs Novel Approaches.

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Carrillo, Celia; Rey, Raquel; Hendrickx, Marc; Del Mar Cavia, María; Alonso-Torre, Sara

2017-09-01

Red beetroot has been ranked among the 10 most potent antioxidant vegetables, although only extraction-based methods have been used to evaluate its total antioxidant capacity. Therefore, the present study aims at comparing the traditional extraction-based method with two more recent approaches (QUENCHER -QUick, Easy, New, CHEap and Reproducible- and GAR -global antioxidant response method), in order to establish their suitability in the case of beetroot. Our results indicate that the total antioxidant capacity of beetroot would be underestimated when using extraction-based procedures, since both QUENCHER and GAR methods resulted in a higher total antioxidant capacity. The effect of a thermal treatment on the total antioxidant capacity of beetroot varies among the methods evaluated and our findings suggest different compounds responsible for the total antioxidant capacity detected in each pre-processing method. Remarkably, the present study demonstrates that the traditional extraction-based method seems useful to screen for (changes in) the "bioavailable" antioxidant potential of the root.

Suppressed peripheral and placental blood lymphoproliferative responses in first pregnancies: relevance to malaria

DEFF Research Database (Denmark)

Rasheed, F N; Bulmer, J N; Dunn, D T

1993-01-01

protein derivative [PPD]) were examined in the peripheral and placental blood of 102 Gambian women at the time of delivery. The lymphoproliferative responses of placental cells were poor to all antigens compared with those of peripheral blood (Candida P PPD P ....003, and 190N P = 0.10). Reduced proliferative capacity of placental mononuclear cells may contribute to heavy parasite colonization of this organ. Proliferation to malarial and PPD but not Candida antigens was selectively suppressed in peripheral and placental blood of primiparae relative to multiparae (F32 P...... = 0.07, 190L P = 0.09, 190N P = 0.007, PPD P = 0.09). Autologous plasma contained factors that suppressed lymphoproliferative responses to the same series of antigens to which the primiparae responded poorly (F32 P PPD P = 0.03). Malarial antibody levels were...

Cadmium stress antioxidant responses and root-to-shoot communication in grafted tomato plants.

Science.gov (United States)

Gratão, Priscila Lupino; Monteiro, Carolina Cristina; Tezotto, Tiago; Carvalho, Rogério Falleiros; Alves, Letícia Rodrigues; Peters, Leila Priscila; Azevedo, Ricardo Antunes

2015-10-01

Many aspects related to ROS modulation of signaling networks and biological processes that control stress responses still remain unanswered. For this purpose, the grafting technique may be a powerful tool to investigate stress signaling and specific responses between plant organs during stress. In order to gain new insights on the modulation of antioxidant stress responses mechanisms, gas-exchange measurements, lipid peroxidation, H2O2 content, proline, superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), ascorbate peroxidase (APX) and guaiacol peroxidase (GPOX) were analyzed in Micro-Tom grafted plants submitted to cadmium (Cd). The results observed revealed that higher amounts of Cd accumulated mainly in the roots and rootstocks when compared to leaves and scions. Macronutrients uptake (Ca, S, P and Mg) decreased in non-grafted plants, but differed among plant parts in all grafted plants. The results showed that the accumulation of proline observed in scions of grafted plants could be associated to the lower MDA contents in the scions of grafted plants. In the presence of Cd, non-grafted plants displayed increased CAT, GR, GPOX and APX activities for both tissues, whilst grafted plants revealed distinct trends that clearly indicate signaling responses from the rootstocks, allowing sufficient time to activate defense mechanisms in shoot. The information available concerning plants subjected to grafting can provide a better understanding of the mechanisms of Cd detoxification involving root-to-shoot signaling, opening new possibilities on strategies which can be used to manipulate heavy metal tolerance, since antioxidant systems are directly involved in such mechanism.

Effect of dietary mannanoligosaccharide supplementation on nutrient digestibility, hindgut fermentation, immune response and antioxidant indices in dogs

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Mahesh M. Pawar

2017-05-01

Full Text Available Abstract Background Use of prebiotics in companion animal nutrition is often considered advantageous over probiotics because of the ease of handling, ability to withstand processing and storage etc. While most of the studies on prebiotic use in dogs have been done with processed food as basal diet, the response in relation to homemade diet feeding is not very well explored. Methods The study was conducted to evaluate the effects of dietary mannanoligosaccharide (MOS supplementation on nutrient digestibility, hindgut fermentation, immune response and antioxidant indices in dogs. Ten Spitz pups were divided into two groups: control (CON with no supplementation, and experimental (MOS wherein the basal diet was supplemented with MOS at 15 g/kg diet. All dogs were fed on a home-prepared diet for a period of 150 days. The study protocol included a digestion trial, periodic blood collection and analysis for lipid profile and erythrocytic antioxidants. Immune response of the animals was assessed towards the end of the feeding period. Results Results revealed no significant (P > 0.05 variations in palatability score, intake and apparent digestibility of nutrients between the groups. Faecal score, faeces voided, faecal pH, concentrations of ammonia, lactate and short-chain fatty acids were comparable (P > 0.05 between the two groups. Cell-mediated immune response, assessed as delayed-type of hypersensitivity response, was significantly higher (P  0.05 in both the groups. Supplementation of MOS lowered (P  0.05 between the two groups. Conclusions The results indicated that supplementation of MOS at the rate of 15 g/kg in the diet of dog augmented the cell-mediated immune response and serum lipid profile without any influences on digestibility of nutrients, hindgut fermentation and antioxidants indices.

Responsibility, thought-action fusion, and thought suppression in Turkish patients with obsessive-compulsive disorder.

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Yorulmaz, O; Karanci, A N; Bastug, B; Kisa, C; Goka, E

2008-03-01

Although an inflated sense of responsibility, thought-action fusion, and thought suppression are influential factors in cognitive models of obsessive-compulsive disorder (OCD), their impact on OCD has generally been demonstrated in samples from Western countries. The aim of the present study is to evaluate these cognitive factors in Turkish patients with OCD, other anxiety disorders, and community controls. Group comparisons showed that responsibility based on self-dangerousness and thought suppression significantly distinguished OCD patients from patients with other anxiety disorders and controls. Moreover, correlation and discriminant function analyses indicated that thought-action fusion in morality and likelihood was also associated with OCD symptoms. The present findings provide support for the international validity and specificity of cognitive factors and model for OCD.

Ibrutinib suppresses alloantibody responses in a mouse model of allosensitization.

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Kim, Irene; Wu, Gordon; Chai, Ning-Ning; Klein, Andrew S; Jordan, Stanley

2017-12-01

Ibrutinib is a Bruton's tyrosine Kinase (BTK) antagonist that inhibits B cell receptor (BCR) signaling. Complete BTK deficiency is associated with absence of B-cells. Ibrutinb is currently approved by FDA for treatment of B-cell malignancies, including Waldenström macroglobulinaemia. We recently carried out studies to determine if ibrutinib could modify alloantibody responses. A mouse model of allogenic sensitization using a C57BL/6 mouse as the recipient of a skin allograft from an HLA-A2 transgenic mouse was utilized to examine the effects of ibrutinib on alloantibody responses and B cell effector functions. Donor-specific antibody (DSA) levels were measured in a flow-cytometric antibody binding assay. Splenic T and B cell subsets and plasma cells were analyzed in flow cytometry. Control mice developed peak levels of DSA IgM at day 14 PTx while the ibrutinib treated mice had significantly lower levels of DSA IgM (p=0.0047). Control mice developed HLA.A2-specific IgG antibodies at day 14 (230±60 MFI) and reached peak levels at day 21 (426±61 MFI). In contrast, mice in the treatment group had low levels of HLA.A2-specific IgG at day 14 (109±59 MFI, p=0.004) and day 21 (241±86 MFI, p=0.003). FACS analysis found a reduction of B220 + or CD19 + B cell population (pibrutinib attenuated recall DSA IgG responses to re-sensitization (pIbrutinib is effective in suppressing alloantibody responses through blocking BTK-mediated BCR signaling, leading to reduction of B cells and short-lived plasma cells in the spleens. Use of ibrutinib may provide benefits to HLA-sensitized transplant patients for alloantibody suppression. Copyright © 2017 Elsevier B.V. All rights reserved.

Dose-dependent suppression by ethanol of transient auditory 40-Hz response.

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Jääskeläinen, I P; Hirvonen, J; Saher, M; Pekkonen, E; Sillanaukee, P; Näätänen, R; Tiitinen, H

2000-02-01

Acute alcohol (ethanol) challenge is known to induce various cognitive disturbances, yet the neural basis of the effect is poorly known. The auditory transient evoked gamma-band (40-Hz) oscillatory responses have been suggested to be associated with various perceptual and cognitive functions in humans; however, alcohol effects on auditory 40-Hz responses have not been investigated to date. The objective of the study was to test the dose-related impact of alcohol on auditory transient evoked 40-Hz responses during a selective-attention task. Ten healthy social drinkers ingested, in four separate sessions, 0.00, 0. 25, 0.50, or 0.75 g/kg of 10% (v/v) alcohol solution. The order of the sessions was randomized and a double-blind procedure was employed. During a selective attention task, 300-Hz standard and 330-Hz deviant tones were presented to the left ear, and 1000-Hz standards and 1100-Hz deviants to the right ear of the subjects (P=0. 425 for each standard, P=0.075 for each deviant). The subjects attended to a designated ear, and were to detect the deviants therein while ignoring tones to the other ear. The auditory transient evoked 40-Hz responses elicited by both the attended and unattended standard tones were significantly suppressed by the 0.50 and 0.75 g/kg alcohol doses. Alcohol suppresses auditory transient evoked 40-Hz oscillations already with moderate blood alcohol concentrations. Given the putative role of gamma-band oscillations in cognition, this finding could be associated with certain alcohol-induced cognitive deficits.

Anti-inflammatory and antioxidant effects of umbelliferone in chronic alcohol-fed rats

Science.gov (United States)

Sim, Mi-Ok; Lee, Hae-In; Ham, Ju Ri; Seo, Kwon-Il; Kim, Myung-Joo

2015-01-01

BACKGROUND/OBJECTIVES Inflammation is associated with various types of acute and chronic alcohol liver diseases. In this study, we examined whether umbelliferone (7-hydroxycoumarin, UF) ameliorates chronic alcohol-induced liver damage by modulating inflammatory response and the antioxidant system. METHODS Rats were fed a Liber-Decarli liquid diet containing 5% alcohol with or without UF (0.05 g/L) for 8 weeks, while normal rats received an isocaloric carbohydrate liquid diet. RESULTS Chronic alcohol intake significantly increased serum tumor necrosis factor-α (TNF-α) and interleukin 6 levels and decreased interleukin 10 level; however, UF supplementation reversed the cytokines related to liver damage. UF significantly suppressed hepatic lipopolysaccharide binding protein, toll-like receptor 4 (TLR4), nuclear factor kappa B, and TNF-α gene expression increases in response to chronic alcohol intake. Masson's trichrome staining revealed that UF improved mild hepatic fibrosis caused by alcohol, and UF also significantly increased the mRNA expressions and activities of superoxide dismutase and catalase in liver, and thus, decreased lipid peroxide and mitochondrial hydrogen peroxide levels. CONCLUSIONS The findings of this study indicate that UF protects against alcohol-induced liver damage by inhibiting the TLR4 signaling pathway and activating the antioxidant system. PMID:26244074

The enzymatic and antioxidative stress response of Lemna minor to copper and a chloroacetamide herbicide.

Science.gov (United States)

Obermeier, Michael; Schröder, Christian A; Helmreich, Brigitte; Schröder, Peter

2015-12-01

Lemna minor L., a widely used model plant for toxicity tests has raised interest for its application to phytoremediation due to its rapid growth and ubiquitous occurrence. In rural areas, the pollution of water bodies with heavy metals and agrochemicals poses a problem to surface water quality. Among problematic compounds, heavy metals (copper) and pesticides are frequently found in water bodies. To establish duckweed as a potential plant for phytoremediation, enzymatic and antioxidative stress responses of Lemna minor during exposure to copper and a chloroacetamide herbicide were investigated in laboratory studies. The present study aimed at evaluating growth and the antioxidative and glutathione-dependent enzyme activity of Lemna plants and its performance in a scenario for phytoremediation of copper and a chloroacetamide herbicide. Lemna minor was grown in Steinberg medium under controlled conditions. Plants were treated with CuSO4 (ion conc. 50 and 100 μg/L) and pethoxamide (1.25 and 2.5 μg/L). Measurements following published methods focused on plant growth, oxidative stress, and basic detoxification enzymes. Duckweed proved to survive treatment with the respective concentrations of both pollutants very well. Its growth was inhibited scarcely, and no visible symptoms occurred. On the cellular basis, accumulation of O2(-) and H2O2 were detected, as well as stress reactions of antioxidative enzymes. Duckweed detoxification potential for organic pollutants was high and increased significantly with incubation. Pethoxamide was found to be conjugated with glutathione. Copper was accumulated in the fronds at high levels, and transient oxidative defense reactions were triggered. This work confirms the significance of L. minor for the removal of copper from water and the conjugation of the selective herbicide pethoxamide. Both organic and inorganic xenobiotics induced different trends of enzymatic and antioxidative stress response. The strong increase of stress

Antioxidant enzymes activities in obese Tunisian children

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Sfar Sonia

2013-01-01

Full Text Available Abstract Background The oxidant stress, expected to increase in obese adults, has an important role in the pathogenesis of many diseases. It results when free radical formation is greatly increased or protective antioxidant mechanisms are compromised. The main objective of this study is to evaluate the antioxidant response to obesity-related stress in healthy children. Methods A hundred and six healthy children (54 obese and 52 controls, aged 6–12 years old, participated in this study. The collected data included anthropometric measures, blood pressure, fasting glucose, total cholesterol, triglycerides and enzymatic antioxidants (Superoxide dismutase: SOD, Catalase: CAT and Glutathione peroxidase: GPx. Results The first step antioxidant response, estimated by the SOD activity, was significantly higher in obese children compared with normal-weight controls (p  Conclusions The obesity-related increase of the oxidant stress can be observed even in the childhood period. In addition to the complications of an increased BMI, obesity itself can be considered as an independent risk factor of free radical production resulting in an increased antioxidant response.

Effect of brewing conditions on antioxidant properties of rosehip tea beverage: study by response surface methodology.

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İlyasoğlu, Huri; Arpa, Tuba Eda

2017-10-01

The aim of this study was to investigate the effects of brewing conditions (infusion time and temperature) on the antioxidant properties of rosehip tea beverage. The ascorbic acid content, total phenolic content (TPC), and ferric reducing antioxidant power (FRAP) of rosehip tea beverage were analysed. A two-factor and three-level central composite design was applied to evaluate the effects of the variables on the responses. The best quadratic models were obtained for all responses. The generated models were validated under the optimal conditions. At the optimal conditions, the rosehip tea beverage had 3.15 mg 100 mL -1 of ascorbic acid, 61.44 mg 100 mL -1 of TPC, and 2591 µmol of FRAP. The best brewing conditions for the rosehip tea beverage were found to be an infusion time of 6-8 min at temperatures of 84-86 °C.

Photoprotection by dietary phenolics against melanogenesis induced by UVA through Nrf2-dependent antioxidant responses

Science.gov (United States)

Chaiprasongsuk, Anyamanee; Onkoksoong, Tasanee; Pluemsamran, Thanyawan; Limsaengurai, Saowalak; Panich, Uraiwan

2015-01-01

Dietary phenolics may play a protective role in UV-mediated skin pigmentation through their antioxidant and UV-absorbing actions. In this study, we investigated whether genetic silencing of Nrf2, regulating the transcription of antioxidant genes, affected melanogenesis in primary human epidermal melanocytes (HEMn) and B16F10 melanoma cells subjected to UVA (8 J/cm2) exposure. Then, we explored the antimelanogenic actions of phenolics; caffeic acid (CA) and ferulic acid (FA) providing partial UVA protection; quercetin (QU) and rutin (RU) providing strong UVA protection and; avobenzone (AV), an efficient UVA filter, in association with modulation of Nrf2-mediated antioxidant defenses in response to UVA insults in B16F10 cells. Upon oxidative insults, Nrf2 silencing promoted melanogenesis in both HEMn and B16F10 cells irradiated with UVA. Stimulation of melanogenesis by UVA correlated with increased ROS and oxidative DNA damage (8-OHdG), GSH depletion as well as a transient downregulation of Nrf2 nuclear translocation and of Nrf2-ARE signaling in B16F10 cells. All test compounds exerted antimelanogenic effects with respect to their abilities to reverse UVA-mediated oxidative damage as well as downregulation of Nrf2 activity and its target antioxidants (GCLC, GST and NQO1) in B16F10 cells. In conclusion, defective Nrf2 may promote melanogenesis under UVA irradiation through oxidative stress mechanisms. Compounds with antioxidant and/or UVA absorption properties could protect against UVA-induced melanogenesis through indirect regulatory effect on Nrf2-ARE pathway. PMID:26765101

High level of dietary soybean oil depresses the growth and anti-oxidative capacity and induces inflammatory response in large yellow croaker Larimichthys crocea.

Science.gov (United States)

Mu, Hua; Shen, Haohao; Liu, Jiahuan; Xie, Fangli; Zhang, Wenbing; Mai, Kangsen

2018-06-01

1β). The replacement of dietary fish oil by soybean oil also induced an over-expression of toll-like receptor 22 and myeloid differentiation factor 88 in liver. In conclusion, dietary soybean oil could suppress growth performance and liver anti-oxidative capacity, and induce inflammatory responses of large yellow croaker. Copyright © 2018. Published by Elsevier Ltd.

Momordica charantia Inhibits Inflammatory Responses in Murine Macrophages via Suppression of TAK1.

Science.gov (United States)

Yang, Woo Seok; Yang, Eunju; Kim, Min-Jeong; Jeong, Deok; Yoon, Deok Hyo; Sung, Gi-Ho; Lee, Seungihm; Yoo, Byong Chul; Yeo, Seung-Gu; Cho, Jae Youl

2018-01-01

Momordica charantia known as bitter melon is a representative medicinal plant reported to exhibit numerous pharmacological activities such as antibacterial, antidiabetic, anti-inflammatory, anti-oxidant, antitumor, and hypoglycemic actions. Although this plant has high ethnopharmacological value for treating inflammatory diseases, the molecular mechanisms by which it inhibits the inflammatory response are not fully understood. In this study, we aim to identify the anti-inflammatory mechanism of this plant. To this end, we studied the effects of its methanol extract (Mc-ME) on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Specifically, we evaluated nitric oxide (NO) production, mRNA expression of inflammatory genes, luciferase reporter gene activity, and putative molecular targets. Mc-ME blocked NO production in a dose-dependent manner in RAW264.7 cells; importantly, no cytotoxicity was observed. Moreover, the mRNA expression levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 were decreased by Mc-ME treatment in a dose-dependent manner. Luciferase assays and nuclear lysate immunoblotting analyses strongly indicated that Mc-ME decreases the levels of p65 [a nuclear factor (NF)-[Formula: see text]B subunit] and c-Fos [an activator protein (AP)-1 subunit]. Whole lysate immunoblotting assays, luciferase assays, and overexpression experiments suggested that transforming growth factor [Formula: see text]-activated kinase 1 (TAK1) is targeted by Mc-ME, thereby suppressing NF-[Formula: see text]B and AP-1 activity via downregulation of extracellular signal-regulated kinases (ERKs) and AKT. These results strongly suggest that Mc-ME exerts its anti-inflammatory activity by reducing the action of TAK1, which also affects the activation of NF-[Formula: see text]B and AP-1.

Suppression of NRF2–ARE activity sensitizes chemotherapeutic agent-induced cytotoxicity in human acute monocytic leukemia cells

Energy Technology Data Exchange (ETDEWEB)

Peng, Hui [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Institute of Disease Control and Prevention, Academy of Military Medical Sciences, Beijing (China); Wang, Huihui [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); Xue, Peng [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Hou, Yongyong [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); Dong, Jian [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Institute of Biology and Medicine, Wuhan University of Science and Technology, Wuhan (China); Zhou, Tong [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Qu, Weidong [Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Peng, Shuangqing [Institute of Disease Control and Prevention, Academy of Military Medical Sciences, Beijing (China); Li, Jin; Carmichael, Paul L. [Unilever, Safety & Environmental Assurance Centre, Colworth Science Park, Sharnbrook, Bedfordshire MK44 1LQ (United Kingdom); Nelson, Bud; Clewell, Rebecca; Zhang, Qiang; Andersen, Melvin E. [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Pi, Jingbo, E-mail: jpi@mail.cmu.edu.cn [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States)

2016-02-01

Nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of the antioxidant response element (ARE)-dependent transcription, plays a pivotal role in chemical detoxification in normal and tumor cells. Consistent with previous findings that NRF2–ARE contributes to chemotherapeutic resistance of cancer cells, we found that stable knockdown of NRF2 by lentiviral shRNA in human acute monocytic leukemia (AML) THP-1 cells enhanced the cytotoxicity of several chemotherapeutic agents, including arsenic trioxide (As{sub 2}O{sub 3}), etoposide and doxorubicin. Using an ARE-luciferase reporter expressed in several human and mouse cells, we identified a set of compounds, including isonicotinic acid amides, isoniazid and ethionamide, that inhibited NRF2–ARE activity. Treatment of THP-1 cells with ethionamide, for instance, significantly reduced mRNA expression of multiple ARE-driven genes under either basal or As{sub 2}O{sub 3}-challenged conditions. As determined by cell viability and cell cycle, suppression of NRF2–ARE by ethionamide also significantly enhanced susceptibility of THP-1 and U937 cells to As{sub 2}O{sub 3}-induced cytotoxicity. In THP-1 cells, the sensitizing effect of ethionamide on As{sub 2}O{sub 3}-induced cytotoxicity was highly dependent on NRF2. To our knowledge, the present study is the first to demonstrate that ethionamide suppresses NRF2–ARE signaling and disrupts the transcriptional network of the antioxidant response in AML cells, leading to sensitization to chemotherapeutic agents. - Highlights: • Identification of novel inhibitors of ARE-dependent transcription • Suppression of NRF2–ARE sensitizes THP-1 cells to chemotherapy. • Ethionamide suppresses ARE-dependent transcriptional activity. • Ethionamide and isoniazid increase the cytotoxicity of As{sub 2}O{sub 3} in AML cells. • Sensitization of THP-1 cells to As{sub 2}O{sub 3} toxicity by ethionamide is NRF2-dependent.

Optimization of microwave-assisted extraction (MAE) of coriander phenolic antioxidants - response surface methodology approach.

Science.gov (United States)

Zeković, Zoran; Vladić, Jelena; Vidović, Senka; Adamović, Dušan; Pavlić, Branimir

2016-10-01

Microwave-assisted extraction (MAE) of polyphenols from coriander seeds was optimized by simultaneous maximization of total phenolic (TP) and total flavonoid (TF) yields, as well as maximized antioxidant activity determined by 1,1-diphenyl-2-picrylhydrazyl and reducing power assays. Box-Behnken experimental design with response surface methodology (RSM) was used for optimization of MAE. Extraction time (X1 , 15-35 min), ethanol concentration (X2 , 50-90% w/w) and irradiation power (X3 , 400-800 W) were investigated as independent variables. Experimentally obtained values of investigated responses were fitted to a second-order polynomial model, and multiple regression analysis and analysis of variance were used to determine fitness of the model and optimal conditions. The optimal MAE conditions for simultaneous maximization of polyphenol yield and increased antioxidant activity were an extraction time of 19 min, an ethanol concentration of 63% and an irradiation power of 570 W, while predicted values of TP, TF, IC50 and EC50 at optimal MAE conditions were 311.23 mg gallic acid equivalent per 100 g dry weight (DW), 213.66 mg catechin equivalent per 100 g DW, 0.0315 mg mL(-1) and 0.1311 mg mL(-1) respectively. RSM was successfully used for multi-response optimization of coriander seed polyphenols. Comparison of optimized MAE with conventional extraction techniques confirmed that MAE provides significantly higher polyphenol yields and extracts with increased antioxidant activity. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Generation of cytotoxic T lymphocytes in vitro. VII. Suppressive effect of irradiated MLC cells on CTL response

International Nuclear Information System (INIS)

Fitch, F.W.; Engers, H.D.; Cerottini, J.C.; Bruner, K.T.

1976-01-01

Irradiated cells obtained from MLC at the peak of the CTL response caused profound suppression of generation of CTL when added in small numbers at the initiation of primary MLC prepared with normal spleen cells. The inhibitory activity of the MLC cells was not affected by irradiation (1000 rads) but was abolished by treatment with anti-theta serum and complement. The suppression was immunologically specific. The response of A (H-2/sup a/) spleen cells toward C3H (H-2/sup k/) alloantigens was suppressed by irradiated MLC cells obtained from MLC prepared with A spleen cells and irradiated C3H-stimulating cells, whereas the response of A spleen cells toward DBA/2 (H-2/sup d/) alloantigens was affected relatively little. However, if irradiated C3H x DBA/2F1 hybrid spleen cells were used to stimulate A spleen cells in MLC, addition of irradiated MLC cells having cytotoxic activity toward C3H antigens abolished the response to both C3H and DBA/2 antigens. The response to DBA/2 antigens was much less affected when a mixture of irradiated C3H and DBA/2 spleen cells was used as stimulating cells. Thus, the presence of MLC cells having cytotoxic activity toward one alloantigen abolished the response to another non-cross-reacting antigen only when both antigens were present on the same F1 hybrid-stimulating cells. This suppression of generation of CTL by irradiated MLC cells apparently involves inactivation of alloantigen-bearing stimulating cells as a result of residual cytotoxic activity of the irradiated MLC cells. This mechanism may be active during the decline in CTL activity noted in the normal immune response in vivo and in vitro

Growth, photosynthesis, and antioxidant responses of Vigna unguiculata L. treated with hydrogen peroxide

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Syed Aiman Hasan

2016-12-01

Full Text Available Cowpea (Vigna unguiculata L. is an important legume well grown in semiarid and arid environment. Hydrogen peroxide solutions (0.1, 0.5, 1.0, and 1.5 mM have been used to optimize growth and photosynthetic performance of cowpea plant at two growth stages [30 and 45 DAS (days of sowing]. Foliar application of H2O2 at 0.5 > 1.0 mM solution at 29 DAS optimally promoted the photosynthetic attributes [leaf chlorophyll content, net photosynthetic rate (PN, water use efficiency, and maximum quantum yield of PSII (Fv/Fm] and growth performance [root and shoot length; fresh and dry weight] of plants where the responses were more significant at the later growth stage. It was favored by activity of enzymes as carbonic anhydrase [CA; E.C. 4.2.1.1] and nitrate reductase [NR, E.C. 1.6.6.1] and those of antioxidant enzymes viz. peroxidase [POX; EC 1.11.1.7], catalase [CAT; EC 1.11.1.6], and superoxide dismutase [SOD; EC 1.15.1.1] and leaf proline content. Strengthened root system and antioxidant activity, particularly leaf proline level appeared to be the key factor for efficient photosynthesis and growth responses.

Radioprotective effects of antioxidative plant flavonoids in mice

International Nuclear Information System (INIS)

Shimoi, Kayoko; Masuda, Shuichi; Shen, Bingrong; Furugori, Michiyo; Kinae, Naohide

1996-01-01

Radioprotective effects of tea infusions and plant flavonoids were investigated by using the micronucleus test for anticlastogenic activity and the thiobarbituric acid assay for antioxidative activity. A single gastric intubation of rooibos tea (Aspalathus linearis) infusion at 1 ml per mouse 2 h prior to γ-ray irradiation (1.5 Gy) reduced the frequency of micronucleated reticulocytes (MNRETs). After the fractionation of rooibos tea infusion, the flavonoid fraction was found to be most anticlastogenic and antioxidative. From this fraction, luteolin was isolated as an effective component. Then, anticlastogenic effects of 12 flavonoids containing luteolin and their antioxidative activities against lipid peroxidation by Fenton's reagent were examined. A good correlation (r=0.717) was observed between both activities. Luteolin showed the most effective potency. A gastric intubation of luteolin (10 μmol/kg) 2 h prior to γ-ray irradiation (6 Gy) suppressed lipid peroxidation in mouse bone marrow and spleen and a trend of protective effect of luteolin against the decrease of endogenous ascorbic acid in mouse bone marrow after γ-ray irradiation (3 Gy) was observed. These results suggest that plant flavonoids, which show antioxidative potency in vitro, work as antioxidants in vivo and their radioprotective effects may be attributed to their scavenging potency towards free radicals such as hydroxyl radicals. Therefore, the flavonoids contained in tea, vegetables and fruits seem to be important as antioxidants in the human diet

The effects of psychoeducation on thought-action fusion, thought suppression, and responsibility.

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Marino-Carper, Teresa; Negy, Charles; Burns, Gillian; Lunt, Rachael A

2010-09-01

The current study examined the effects of a psychoeducational intervention designed to target thought-action fusion (TAF) on TAF, thought suppression, and responsibility cognitions. 139 undergraduate students (25 male; 114 female) who were relatively high in TAF with respect to their peers served as participants. Immediately following intervention, individuals who had received psychoeducation regarding TAF reported significantly lower morality TAF scores than individuals who had received psychoeducation regarding thoughts in general and individuals in the control group. At the two-week follow-up assessment, the likelihood TAF scores of those who had received psychoeducation regarding TAF were significantly lower than those of the control group. In addition, the group that received psychoeducation regarding TAF was the only group that did not experience a significant increase in thought suppression from baseline to post-intervention, and was also the only group to experience an increase in both frequency of and belief in low-responsibility thoughts from baseline to follow-up. Implications are discussed. (c) 2010 Elsevier Ltd. All rights reserved.

Antioxidant capacity and physical exercise

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A Marciniak

2009-09-01

Full Text Available The aim of this article is a presentation of current knowledge regarding the changes of plasma antioxidant capacity observed in response to physical exercise. Human body created the enzymatic and non-enzymatic systems, which play a protective role in the harmful impact of free radicals. Those two systems constitute what is known as the plasma total antioxidant capacity. The amount of reactive oxygen species (ROS and reactive nitrogen species (NOS in combination with oxidation processes increases in some tissues during physiological response to physical exercise. These changes are observed after single bout of exercise as well as after regular training. The response of human body to physical exercise can be analysed using various models of exercise test. Application of repeated type of exhaustion allows for characterizing the ability of human body to adjust to the increased energy loss and increased oxygen consumption. This article presents the characteristics of components of plasma antioxidant capacity, the mechanisms of free radicals production and their role in human body. It discusses also the currently used methods of detecting changes in total antioxidant capacity and its individual elements in response to single bout of exercise and regular training. It presents the review of literature about research performed in groups of both regularly training and low exercise activity individuals as well as in group of healthy subjects and patients with circulation diseases.

Melatonin modulates inflammatory response and suppresses burn-induced apoptotic injury

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Ganka Bekyarova

2017-04-01

Full Text Available Introduction: Melatonin, the principal secretory product of the pineal gland, has antioxidant functions as a potent antioxidant and free radical scavenger. Objectives of the present study were to investigate the effect of melatonin against inflammatory response, burn-induced oxidative damage and apoptotic changes of rat liver. Methods: Melatonin (10 mg /kg, i.p. was applied immediately after 30% of total body surface area (TBSA burns on male Wistar rats. The level of malondialdehyde (MDA as a marker of an oxidative stress was quantified by thiobarbituric method. Hepatic TNFα and IL-10 as inflammatory markers were assayed by ELISA. Using light immunоchistochemistry the expression Ki67 proliferative marker was investigated. Results: Hepatic MDA and TNF-α levels increased significantly following burns without any change in IL-10 level. Intracellular vacuolization, hepatic cell degeneration and apoptosis occurred in rats after burns. The number of apoptotic cells was increased whereas no significant increase in Ki67 proliferative marker. Melatonin decreased the MDA and TNF-α content and increased the IL-10 level. It also limited the degenerative changes and formation of apoptotic cells in rat liver but did not increase expression of the marker of proliferation. In conclusion, our data show that melatonin relieves burn-induced hepatic damage associated with modulation of the proinflammatory/anti-inflammatory balance, mitigation of lipid peroxidation and hepatic apoptosis.

Cortisol responses on the dexamethasone suppression test among women with Bulimia-spectrum eating disorders: associations with clinical symptoms.

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Bruce, Kenneth R; Steiger, Howard; Israël, Mimi; Groleau, Patricia; Ng Ying Kin, N M K; Ouellette, Anne-Sophie; Sycz, Lindsay; Badawi, Ghislaine

2012-08-07

Evidence associates Bulimia Nervosa (BN) with altered functioning of the hypothalamic-pituitary-adrenal (HPA) axis, but the clinical implications of such alterations need to be better understood. We contrasted cortisol responses to the dexamethasone suppression test (DST) in bulimic and non-eating disordered women and examined relationships among DST cortisol responses, eating symptoms and co-morbid disturbances. Sixty women with Bulimia Spectrum (BS) Disorders (either BN or normal weight Eating Disorder NOS with regular binge eating or purging) and 54 non-eating disordered women of similar age and body mass index participated in a 0.5 mg DST, and completed interviews and questionnaires assessing eating symptoms and co-morbid psychopathology. Compared with the normal-eater group, the BS women demonstrated significantly less DST suppression. Among BS women, DST non-suppression was associated with more severe depression, anxiety and eating preoccupations. Our findings show BS women to show less DST suppression compared to normal eater women, and results link extent of non-suppression, in BS individuals, to severity of depression, anxiety and eating preoccupations. Copyright © 2012 Elsevier Inc. All rights reserved.

Adaptive Filtering for Aeroservoelastic Response Suppression, Phase I

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National Aeronautics and Space Administration — CSA Engineering proposes the design of an adaptive aeroelastic mode suppression for advanced fly-by-wire aircraft, which will partition the modal suppression...

Antioxidant gene expression and metabolic responses of earthworms (Eisenia fetida) after exposure to various concentrations of hexabromocyclododecane.

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Shi, Yajuan; Xu, Xiangbo; Chen, Juan; Liang, Ruoyu; Zheng, Xiaoqi; Shi, Yajing; Wang, Yurong

2018-01-01

Hexabromocyclododecane (HBCD), a ubiquitous suspected contaminant, is one of the world's most prominent brominated flame retardants (BFRs). In the present study, earthworms (Eisenia fetida) were exposed to HBCD. The expression of selected antioxidant enzyme genes was measured, and the metabolic responses were assessed using nuclear magnetic resonance (NMR) to identify the molecular mechanism of the antioxidant stress reaction and the metabolic reactions of earthworms to HBCD. A significant up-regulation (p  0.05). Principal component analysis (PCA) of the metabolic responses showed that all groups could be clearly differentiated, and the highest concentration dose group was the most distant from the control group. Except for fumarate, the measured metabolites, which included adenosine triphosphate (ATP), valine, lysine, glycine, betaine and lactate, revealed significant (p earthworm exposure studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Response of total phenolic content and antioxidant activities of bush ...

African Journals Online (AJOL)

The positive health benefits associated with tea are made possible by the antioxidant activity of phenolic compounds present in tea. The total phenolic content and antioxidant activity of bush tea (Athrixia phylicoides DC.) and special tea (Monsonia burkeana) were studied. The extractions were done in triplicate using cold ...

Differential Antioxidant Responses and Perturbed Porphyrin Biosynthesis after Exposure to Oxyfluorfen and Methyl Viologen in Oryza sativa.

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Pham, Nhi-Thi; Kim, Jin-Gil; Jung, Sunyo

2015-07-21

We compared antioxidant responses and regulation of porphyrin metabolism in rice plants treated with oxyfluorfen (OF) or methyl viologen (MV). Plants treated with MV exhibited not only greater increases in conductivity and malondialdehyde but also a greater decline in Fv/Fm, compared to plants treated with OF. MV-treated plants had greater increases in activities of superoxide dismutase (SOD) and catalase (CAT) as well as transcript levels of SODA and CATA than OF-treated plants after 28 h of the treatments, whereas increases in ascorbate peroxidase (APX) activity and transcript levels of APXA and APXB were greater in OF-treated plants. Both OF- and MV-treated plants resulted in not only down-regulation of most genes involved in porphyrin biosynthesis but also disappearance of Mg-porphyrins during the late stage of photooxidative stress. By contrast, up-regulation of heme oxygenase 2 (HO2) is possibly part of an efficient antioxidant response to compensate photooxidative damage in both treatments. Our data show that down-regulated biosynthesis and degradation dynamics of porphyrin intermediates have important roles in photoprotection of plants from perturbed porphyrin biosynthesis and photosynthetic electron transport. This study suggests that porphyrin scavenging as well as strong antioxidative activities are required for mitigating reactive oxygen species (ROS) production under photooxidative stress caused by OF and MV.

Impact of maternal melatonin suppression on forced swim and tail suspension behavioral despair tests in adult offspring.

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Voiculescu, S E; Rosca, A E; Zeca, V; Zagrean, L; Zagrean, A M

2015-01-01

Melatonin is an essential hormone, which regulates circadian rhythms and has antioxidative and anticarcinogenic effects. As melatonin secretion is suppressed by light, this effect was examined on the offspring of the Wistar rat females exposed to continuous light (500 lux) during the second half of the pregnancy (day 12 to 21). Control rats were kept under a 12:12 light-dark cycle. The resulted male offspring have been behaviorally assessed for depression after postnatal day 60 by using Forced Swim Test (FST) and Tail Suspension Test (TST). Animals resulted from the melatonin deprived pregnancies have developed an abnormal response in the TST, but a normal FST behavior. Also, TST active movement was different in the melatonin suppression group compared to the control group. These findings suggest that intrauterine melatonin deprivation might be linked to the depressive like behavior in adult male offspring.

Optimization of ultrasonic-assisted extraction of antioxidant compounds from Guava (Psidium guajava L.) leaves using response surface methodology.

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Kong, Fansheng; Yu, Shujuan; Feng, Zeng; Wu, Xinlan

2015-01-01

To optimization of extraction of antioxidant compounds from guava (Psidium guajava L.) leaves and showed that the guava leaves are the potential source of antioxidant compounds. The bioactive polysaccharide compounds of guava leaves (P. guajava L.) were obtained using ultrasonic-assisted extraction. Extraction was carried out according to Box-Behnken central composite design, and independent variables were temperature (20-60°C), time (20-40 min) and power (200-350 W). The extraction process was optimized by using response surface methodology for the highest crude extraction yield of bioactive polysaccharide compounds. The optimal conditions were identified as 55°C, 30 min, and 240 W. 1,1-diphenyl-2-picryl-hydrazyl and hydroxyl free radical scavenging were conducted. The results of quantification showed that the guava leaves are the potential source of antioxidant compounds.

Oxytocin administration suppresses hypothalamic activation in response to visual food cues.

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van der Klaauw, Agatha A; Ziauddeen, Hisham; Keogh, Julia M; Henning, Elana; Dachi, Sekesai; Fletcher, Paul C; Farooqi, I Sadaf

2017-06-27

The aim of this study was to use functional neuroimaging to investigate whether oxytocin modulates the neural response to visual food cues in brain regions involved in the control of food intake. Twenty-four normal weight volunteers received intranasal oxytocin (24 IU) or placebo in a double-blind, randomized crossover study. Measurements were made forty-five minutes after dosing. On two occasions, functional MRI (fMRI) scans were performed in the fasted state; the blood oxygen level-dependent (BOLD) response to images of high-calorie foods versus low-calorie foods was measured. Given its critical role in eating behaviour, the primary region of interest was the hypothalamus. Secondary analyses examined the parabrachial nuclei and other brain regions involved in food intake and food reward. Intranasal oxytocin administration suppressed hypothalamic activation to images of high-calorie compared to low-calorie food (P = 0.0125). There was also a trend towards suppression of activation in the parabrachial nucleus (P = 0.0683). No effects of intranasal oxytocin were seen in reward circuits or on ad libitum food intake. Further characterization of the effects of oxytocin on neural circuits in the hypothalamus is needed to establish the utility of targeting oxytocin signalling in obesity.

Comparison of an antioxidant system in tolerant and susceptible wheat seedlings in response to salt stress

Energy Technology Data Exchange (ETDEWEB)

Feki, K.; Tounsi, S.; Brini, F.

2017-07-01

It has been demonstrated previously that the physiological and molecular analysis of seedlings of the tolerant (Om Rabia3) and susceptible (Mahmoudi) Tunisian wheat genotypes were different at short and long-term response to salinity. In this study, we examined the antioxidant defence system in seedlings of these two cultivars at short-term response to different NaCl concentrations. The findings showed that high salinity tolerance of cv. Om Rabia3, as manifested by lower decrease in its dry biomass, was associated with lower malondialdehyde and hydrogen peroxide contents, lower accumulation of the superoxide (O2⎯) in the roots and the shoots, and also lower decrease in ascorbate content than those in cv. Mahmoudi. Moreover, the expression of some genes coding for antioxidant enzymes such as the catalase, the superoxide dismutase and the peroxidase were enhanced by NaCl stress especially in the salt-tolerant cultivar. In parallel, their activities were increased in response to the same condition of stress and especially in the cv. Om Rabia3. Taken together, these data suggested that the capacity to limit oxidative damage is important for NaCl tolerance of durum wheat.

[Correction of lipid peroxidation and antioxidant system disorders by bioflavonoids during modeling of cholesterol atherosclerosis in rabbits].

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Shysh, A M; Pashevin, D O; Dosenko, V Ie; Moĭbenko, O O

2011-01-01

We have studied the influence of bioflavonoids (quercetin, corvitin) on lipid peroxidation and antioxidant enzymes in the modeling of cholesterol atherosclerosis in rabbits. It has been shown that simultaneous administration of the quercetin derivative corvitin suppressed lipid peroxidation. We showed that under hypercholesterolemia, the concentration of malone dialdehyde in myocardial tissue in rabbits is significantly increased, while administration of bioflavonoids decreased the concentration of malone dialdehyde by 38.3%. Furthermore, corvitin caused activating effects on antioxidant enzymes superoxide dismutase and catalase in cardiac tissue. Our data suggest that bioflavonoids are able to suppress lipid peroxidation and prevent the decrease ofantioxidant enzymes activity in rabbits with cholesterol-rich diet induced atherosclerosis.

Anti-plasmodial and antioxidant activities of methanol extract of the ...

African Journals Online (AJOL)

This study was aimed at investigating the anti-plasmodial and antioxidant activities of the extract of the leaf of Lophira lanceolata, a traditional medicine recipe. The methanol extract (ME) obtained by 72 h cold maceration was evaluated for acute toxicity test (LD50) and phytochemical constituents. The suppressive and ...

Blood antioxidant and oxidative stress biomarkers acute responses to a 1000-m kayak sprint in elite male kayakers.

Science.gov (United States)

Teixeira, V H; Valente, H F; Casal, S I; Marques, F P; Moreira, P A

2013-02-01

This study aimed to investigate the response of blood antioxidants and biomarkers of lipid peroxidation, muscle damage and inflammation to a 1000m kayak trial in elite male kayakers. Enzymatic (superoxide dismutase [SOD], glutathione reductase [Gr] and glutathione peroxidase [GPx] activities) and non-enzymatic (total antioxidant status [TAS], uric acid, α-tocopherol, α-carotene, β-carotene, lycopene and lutein and zeaxanthin) antioxidants, thiobarbituric acid reactive substances (TBARS), creatine kinase (CK), interleukin-6 (IL-6) and cortisol were determined in 15 elite male kayakers before and 15 min after a 1000-m kayak simulated race. Both enzymatic and non-enzymatic antioxidants were unaffected by exercise, with the exception of α-carotene which decreased (P=0.013). Uric acid levels were incremented following exercise (P=0.016). The acute exercise resulted in a significant decrease in TAS (P=0.001) and in an increase in CK (P=0.023), TBARS (P<0.001) and IL-6 (P=0.028). Our study suggests that a 1000-m kayak simulated race induces oxidative stress and damage in highly-trained kayakers.

Optimization of Ultrasound-Assisted Extraction of Natural Antioxidants from the Flower of Jatropha integerrima by Response Surface Methodology.

Science.gov (United States)

Xu, Dong-Ping; Zhou, Yue; Zheng, Jie; Li, Sha; Li, An-Na; Li, Hua-Bin

2015-12-24

An ultrasound-assisted extraction (UAE) method was developed for the efficient extraction of natural antioxidants from the flowers of Jatropha integerrima. Four independent variables, including ethanol concentration, solvent/material ratio, ultrasound irradiation time and temperature were studied by single factor experiments. Then, the central composite rotatable design and response surface methodology were employed to investigate the effect of three key parameters (ethanol concentration, solvent/material ratio, and ultrasound irradiation time) on the antioxidant activities of the flower extracts. The optimal extraction conditions were an ethanol concentration of 59.6%, solvent/material ratio of 50:1, ultrasound irradiation time of 7 min, and ultrasound irradiation temperature of 40 °C. Under these conditions, the optimized experimental value was 1103.38 ± 16.11 µmol Trolox/g dry weight (DW), which was in accordance with the predicted value (1105.49 µmol Trolox/g DW). Furthermore, the antioxidant activities of flower extracts obtained by UAE were compared with those produced by the traditional maceration and Soxhlet extraction methods, and UAE resulted in higher antioxidant activities after a shorter time at a lower temperature. The results obtained are helpful for the full utilization of Jatropha integerrima, and also indicate that ultrasound-assisted extraction is an efficient method for the extraction of natural antioxidants from plant materials.

Optimization of Ultrasound-Assisted Extraction of Natural Antioxidants from the Flower of Jatropha integerrima by Response Surface Methodology

Directory of Open Access Journals (Sweden)

Dong-Ping Xu

2015-12-01

Full Text Available An ultrasound-assisted extraction (UAE method was developed for the efficient extraction of natural antioxidants from the flowers of Jatropha integerrima. Four independent variables, including ethanol concentration, solvent/material ratio, ultrasound irradiation time and temperature were studied by single factor experiments. Then, the central composite rotatable design and response surface methodology were employed to investigate the effect of three key parameters (ethanol concentration, solvent/material ratio, and ultrasound irradiation time on the antioxidant activities of the flower extracts. The optimal extraction conditions were an ethanol concentration of 59.6%, solvent/material ratio of 50:1, ultrasound irradiation time of 7 min, and ultrasound irradiation temperature of 40 °C. Under these conditions, the optimized experimental value was 1103.38 ± 16.11 µmol Trolox/g dry weight (DW, which was in accordance with the predicted value (1105.49 µmol Trolox/g DW. Furthermore, the antioxidant activities of flower extracts obtained by UAE were compared with those produced by the traditional maceration and Soxhlet extraction methods, and UAE resulted in higher antioxidant activities after a shorter time at a lower temperature. The results obtained are helpful for the full utilization of Jatropha integerrima, and also indicate that ultrasound-assisted extraction is an efficient method for the extraction of natural antioxidants from plant materials.

The nuclear factor (erythroid-derived 2)-like 2 (NRF2) antioxidant response promotes melanocyte viability and reduces toxicity of the vitiligo-inducing phenol monobenzone.

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Arowojolu, Omotayo A; Orlow, Seth J; Elbuluk, Nada; Manga, Prashiela

2017-07-01

Vitiligo, characterised by progressive melanocyte death, can be initiated by exposure to vitiligo-inducing phenols (VIPs). VIPs generate oxidative stress in melanocytes and activate the master antioxidant regulator NRF2. While NRF2-regulated antioxidants are reported to protect melanocytes from oxidative stress, the role of NRF2 in the melanocyte response to monobenzone, a clinically relevant VIP, has not been characterised. We hypothesised that activation of NRF2 may protect melanocytes from monobenzone-induced toxicity. We observed that knockdown of NRF2 or NRF2-regulated antioxidants NQO1 and PRDX6 reduced melanocyte viability, but not viability of keratinocytes and fibroblasts, suggesting that melanocytes were preferentially dependent upon NRF2 activity for growth compared to other cutaneous cells. Furthermore, melanocytes activated the NRF2 response following monobenzone exposure and constitutive NRF2 activation reduced monobenzone toxicity, supporting NRF2's role in the melanocyte stress response. In contrast, melanocytes from individuals with vitiligo (vitiligo melanocytes) did not activate the NRF2 response as efficiently. Dimethyl fumarate-mediated NRF2 activation protected normal and vitiligo melanocytes against monobenzone-induced toxicity. Given the contribution of oxidant-antioxidant imbalance in vitiligo, modulation of this pathway may be of therapeutic interest. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mothers' responses to children's negative emotions and child emotion regulation: the moderating role of vagal suppression.

Science.gov (United States)

Perry, Nicole B; Calkins, Susan D; Nelson, Jackie A; Leerkes, Esther M; Marcovitch, Stuart

2012-07-01

The current study examined the moderating effect of children's cardiac vagal suppression on the association between maternal socialization of negative emotions (supportive and nonsupportive responses) and children's emotion regulation behaviors. One hundred and ninety-seven 4-year-olds and their mothers participated. Mothers reported on their reactions to children's negative emotions and children's regulatory behaviors. Observed distraction, an adaptive self-regulatory strategy, and vagal suppression were assessed during a laboratory task designed to elicit frustration. Results indicated that children's vagal suppression moderated the association between mothers' nonsupportive emotion socialization and children's emotion regulation behaviors such that nonsupportive reactions to negative emotions predicted lower observed distraction and lower reported emotion regulation behaviors when children displayed lower levels of vagal suppression. No interaction was found between supportive maternal emotion socialization and vagal suppression for children's emotion regulation behaviors. Results suggest physiological regulation may serve as a buffer against nonsupportive emotion socialization. Copyright © 2011 Wiley Periodicals, Inc.

Differential antioxidative enzyme responses of Jatropha curcas L. to chromium stress.

Science.gov (United States)

Yadav, Santosh Kumar; Dhote, Monika; Kumar, Phani; Sharma, Jitendra; Chakrabarti, Tapan; Juwarkar, Asha A

2010-08-15

Chromium (Cr) tolerant and accumulation capability of Jatropha curcas L. was tested in Cr spiked soil amended with biosludge and biofertilizer. Plants were cultivated in soils containing 0, 25, 50, 100 and 250 mg kg(-1) of Cr for one year with and without amendment. Plant tissue analysis showed that combined application of biosludge and biofertilizer could significantly reduce Cr uptake and boost the plant biomass, whereas biofertilizer alone did not affect the uptake and plant growth. Antioxidative responses of catalase (CAT), ascorbate peroxidase (APX) and glutathione S-transferase (GST) were increased with increasing Cr concentration in plant. Hyperactivity of the CAT and GST indicated that antioxidant enzymes played an important role in protecting the plant from Cr toxicity. However, APX took a little part in detoxification of H(2)O(2) due to its sensitivity to Cr. Therefore, reduced APX activity was recorded. Reduced glutathione (GSH) activity was recorded in plant grown on/above 100 mg kg(-1) of Cr in soil. The study concludes that J. curcas could grow under chromium stress. Furthermore, the results encouraged that J. curcas is a suitable candidate for the restoration of Cr contaminated soils with the concomitant application of biosludge and biofertilizer. Copyright 2010 Elsevier B.V. All rights reserved.

Benzodiazepine temazepam suppresses the transient auditory 40-Hz response amplitude in humans.

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Jääskeläinen, I P; Hirvonen, J; Saher, M; Pekkonen, E; Sillanaukee, P; Näätänen, R; Tiitinen, H

1999-06-18

To discern the role of the GABA(A) receptors in the generation and attentive modulation of the transient auditory 40-Hz response, the effects of the benzodiazepine temazepam (10 mg) were studied in 10 healthy social drinkers, using a double-blind placebo-controlled design. Three hundred Hertz standard and 330 Hz rare deviant tones were presented to the left, and 1000 Hz standards and 1100 Hz deviants to the right ear of the subjects. Subjects attended to a designated ear and were to detect deviants therein while ignoring tones to the other. Temazepam significantly suppressed the amplitude of the 40-Hz response, the effect being equal for attended and non-attended tone responses. This suggests involvement of GABA(A) receptors in transient auditory 40-Hz response generation, however, not in the attentive modulation of the 40-Hz response.

Differential coral bleaching-Contrasting the activity and response of enzymatic antioxidants in symbiotic partners under thermal stress.

Science.gov (United States)

Krueger, Thomas; Hawkins, Thomas D; Becker, Susanne; Pontasch, Stefanie; Dove, Sophie; Hoegh-Guldberg, Ove; Leggat, William; Fisher, Paul L; Davy, Simon K

2015-12-01

Mass coral bleaching due to thermal stress represents a major threat to the integrity and functioning of coral reefs. Thermal thresholds vary, however, between corals, partly as a result of the specific type of endosymbiotic dinoflagellate (Symbiodinium sp.) they harbour. The production of reactive oxygen species (ROS) in corals under thermal and light stress has been recognised as one mechanism that can lead to cellular damage and the loss of their symbiont population (Oxidative Theory of Coral Bleaching). Here, we compared the response of symbiont and host enzymatic antioxidants in the coral species Acropora millepora and Montipora digitata at 28°C and 33°C. A. millepora at 33°C showed a decrease in photochemical efficiency of photosystem II (PSII) and increase in maximum midday excitation pressure on PSII, with subsequent bleaching (declining photosynthetic pigment and symbiont density). M. digitata exhibited no bleaching response and photochemical changes in its symbionts were minor. The symbiont antioxidant enzymes superoxide dismutase, ascorbate peroxidase, and catalase peroxidase showed no significant upregulation to elevated temperatures in either coral, while only catalase was significantly elevated in both coral hosts at 33°C. Increased host catalase activity in the susceptible coral after 5days at 33°C was independent of antioxidant responses in the symbiont and preceded significant declines in PSII photochemical efficiencies. This finding suggests a potential decoupling of host redox mechanisms from symbiont photophysiology and raises questions about the importance of symbiont-derived ROS in initiating coral bleaching. Copyright © 2015 Elsevier Inc. All rights reserved.

Rhizobial symbiosis effect on the growth, metal uptake, and antioxidant responses of Medicago lupulina under copper stress.

Science.gov (United States)

Kong, Zhaoyu; Mohamad, Osama Abdalla; Deng, Zhenshan; Liu, Xiaodong; Glick, Bernard R; Wei, Gehong

2015-08-01

The effects of rhizobial symbiosis on the growth, metal uptake, and antioxidant responses of Medicago lupulina in the presence of 200 mg kg(-1) Cu(2+) throughout different stages of symbiosis development were studied. The symbiosis with Sinorhizobium meliloti CCNWSX0020 induced an increase in plant growth and nitrogen content irrespective of the presence of Cu(2+). The total amount of Cu uptake of inoculated plants significantly increased by 34.0 and 120.4% in shoots and roots, respectively, compared with non-inoculated plants. However, although the rhizobial symbiosis promoted Cu accumulation both in shoots and roots, the increase in roots was much higher than in shoots, thus decreasing the translocation factor and helping Cu phytostabilization. The rate of lipid peroxidation was significantly decreased in both shoots and roots of inoculated vs. non-inoculated plants when measured either 8, 13, or 18 days post-inoculation. In comparison with non-inoculated plants, the activities of superoxide dismutase and ascorbate peroxidase of shoots of inoculated plants exposed to excess Cu were significantly elevated at different stages of symbiosis development; similar increases occurred in the activities of superoxide dismutase, catalase, and glutathione reductase of inoculated roots. The symbiosis with S. meliloti CCNWSX0020 also upregulated the corresponding genes involved in antioxidant responses in the plants treated with excess Cu. The results indicated that the rhizobial symbiosis with S. meliloti CCNWSX0020 not only enhanced plant growth and metal uptake but also improved the responses of plant antioxidant defense to excess Cu stress.

Differential roles of resistance to proactive interference and suppression of prepotent responses in overgeneral memory.

Science.gov (United States)

Comas, Michelle; Valentino, Kristin; Johnson, Anne F; Gibson, Bradley S; Taylor, Courtney

2018-06-12

Overgeneral memory (OGM), difficulty in retrieving specific autobiographical memories, is a robust phenomenon related to the onset and course of depressive and posttraumatic stress disorders. Inhibitory mechanisms are theorized to underlie OGM; however, empirical support for this link is equivocal. The current study examines the differential roles of two aspects of inhibitory control in association with OGM: suppression of prepotent responses and resistance to proactive interference (PI). Only resistance to PI was expected to be negatively related to OGM, whereby individuals with greater ability to resist PI would have reduced OGM. Participants (n = 49) completed a self-report measure of depressive symptoms and engaged in two tasks aimed at assessing resistance to PI and suppression of prepotent responses. Participants also completed a task assessing overgeneral autobiographical memory. As hypothesized, resistance to PI, but not suppression of prepotent responses negatively predicted OGM above and beyond the influence of depressive symptoms. Because a double dissociation was not examined, we cannot address the potential independence of the submechanisms of inhibitory control that we assessed. Results exemplify the differential associations of two components of inhibition and OGM, suggesting that resistance to PI, in particular, may contribute to the development and/or maintenance of OGM and associated depressive disorders. Directions for future research are discussed. Copyright © 2018. Published by Elsevier Ltd.

Antioxidant Intake and Antitumor Therapy: Toward Nutritional Recommendations for Optimal Results

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Mut-Salud, Nuria; Álvarez, Pablo Juan; Garrido, Jose Manuel; Carrasco, Esther; Aránega, Antonia; Rodríguez-Serrano, Fernando

2016-01-01

The role of the induction of oxidative stress as the mechanism of action of many antitumor drugs is acquiring an increasing interest. In such cases, the antitumor therapy success may be conditioned by the antioxidants present in our own body, which can be synthesized de novo (endogenous) or incorporated through the diet and nutritional supplements (exogenous). In this paper, we have reviewed different aspects of antioxidants, including their classification, natural sources, importance in diet, consumption of nutritional supplements, and the impact of antioxidants on health. Moreover, we have focused especially on the study of the interaction between antioxidants and antitumor therapy, considering both radiotherapy and chemotherapy. In this regard, we found that the convenience of administration of antioxidants during cancer treatment still remains a very controversial issue. In general terms, antioxidants could promote or suppress the effectiveness of antitumor treatment and even protect healthy tissues against damage induced by oxidative stress. The effects may depend on many factors discussed in the paper. These factors should be taken into consideration in order to achieve precise nutritional recommendations for patients. The evidence at the moment suggests that the supplementation or restriction of exogenous antioxidants during cancer treatment, as appropriate, could contribute to improving its efficiency. PMID:26682013

Antioxidant Intake and Antitumor Therapy: Toward Nutritional Recommendations for Optimal Results

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Nuria Mut-Salud

2016-01-01

Full Text Available The role of the induction of oxidative stress as the mechanism of action of many antitumor drugs is acquiring an increasing interest. In such cases, the antitumor therapy success may be conditioned by the antioxidants present in our own body, which can be synthesized de novo (endogenous or incorporated through the diet and nutritional supplements (exogenous. In this paper, we have reviewed different aspects of antioxidants, including their classification, natural sources, importance in diet, consumption of nutritional supplements, and the impact of antioxidants on health. Moreover, we have focused especially on the study of the interaction between antioxidants and antitumor therapy, considering both radiotherapy and chemotherapy. In this regard, we found that the convenience of administration of antioxidants during cancer treatment still remains a very controversial issue. In general terms, antioxidants could promote or suppress the effectiveness of antitumor treatment and even protect healthy tissues against damage induced by oxidative stress. The effects may depend on many factors discussed in the paper. These factors should be taken into consideration in order to achieve precise nutritional recommendations for patients. The evidence at the moment suggests that the supplementation or restriction of exogenous antioxidants during cancer treatment, as appropriate, could contribute to improving its efficiency.

Multi-criteria optimization for ultrasonic-assisted extraction of antioxidants from Pericarpium Citri Reticulatae using response surface methodology, an activity-based approach.

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Zeng, Shanshan; Wang, Lu; Zhang, Lei; Qu, Haibin; Gong, Xingchu

2013-06-01

An activity-based approach to optimize the ultrasonic-assisted extraction of antioxidants from Pericarpium Citri Reticulatae (Chenpi in Chinese) was developed. Response surface optimization based on a quantitative composition-activity relationship model showed the relationships among product chemical composition, antioxidant activity of extract, and parameters of extraction process. Three parameters of ultrasonic-assisted extraction, including the ethanol/water ratio, Chenpi amount, and alkaline amount, were investigated to give optimum extraction conditions for antioxidants of Chenpi: ethanol/water 70:30 v/v, Chenpi amount of 10 g, and alkaline amount of 28 mg. The experimental antioxidant yield under the optimum conditions was found to be 196.5 mg/g Chenpi, and the antioxidant activity was 2023.8 μmol Trolox equivalents/g of the Chenpi powder. The results agreed well with the second-order polynomial regression model. This presented approach promised great application potentials in both food and pharmaceutical industries. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The response of antioxidant systems in Nostoc sphaeroides against UV-B radiation and the protective effects of exogenous antioxidants

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Wang, Gaohong; Hu, Chunxiang; Li, Dunhai; Zhang, Delu; Li, Xiaoyan; Chen, Kun; Liu, Yongding

UV radiation is one of many harmful factors found in space that are detrimental to organisms on earth in space exploration. In the present work, we examined the role of antioxidant system in Nostoc sphaeroides Kütz (Cyanobacterium) and the effects of exogenously applied antioxidant molecules on its photosynthetic rate under UV-B radiation. It was found that UV-B radiation promoted the activity of antioxidant system to protect photosystem II (PSII) and exogenously applied antioxidant: sodium nitroprusside (SNP) and N-acetylcysteine (NAC) had an obvious protection on PSII activity under UV-B radiation. The activity of superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), peroxidase (POD, EC 1.11.1.7) and content of MDA (malondialdehyde) and ASC (ascorbate) were improved by 0.5 mM and 1 mM SNP, but 0.1 mM SNP decreased the activity of antioxidant system. Addition of exogenous NAC decreased the activity of SOD, POD, CAT and the content MDA and ASC. In contrast, exogenously applied NAC increased GSH content. The results suggest that exogenous SNP and NAC may protect algae by different mechanisms: SNP may play double roles as both sources of reactive free radicals as well as ROS scavengers in mediating the protective role of PSII on algae under UV-B radiation. On the other hand, NAC functions as an antioxidant or precursor of glutathione, which could protect PSII directly from UV-B radiation.

Dispositional fear, negative affectivity, and neuroimaging response to visually suppressed emotional faces.

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Vizueta, Nathalie; Patrick, Christopher J; Jiang, Yi; Thomas, Kathleen M; He, Sheng

2012-01-02

"Invisible" stimulus paradigms provide a method for investigating basic affective processing in clinical and non-clinical populations. Neuroimaging studies utilizing continuous flash suppression (CFS) have shown increased amygdala response to invisible fearful versus neutral faces. The current study used CFS in conjunction with functional MRI to test for differences in brain reactivity to visible and invisible emotional faces in relation to two distinct trait dimensions relevant to psychopathology: negative affectivity (NA) and fearfulness. Subjects consisted of college students (N=31) assessed for fear/fearlessness along with dispositional NA. The main brain regions of interest included the fusiform face area (FFA), superior temporal sulcus (STS), and amygdala. Higher NA, but not trait fear, was associated with enhanced response to fearful versus neutral faces in STS and right amygdala (but not FFA), within the invisible condition specifically. The finding that NA rather than fearfulness predicted degree of amygdala reactivity to suppressed faces implicates the input subdivision of the amygdala in the observed effects. Given the central role of NA in anxiety and mood disorders, the current data also support use of the CFS methodology for investigating the neurobiology of these disorders. Copyright © 2011 Elsevier Inc. All rights reserved.

Mechanisms of cross-suppression of TNP-specific plaque forming cell responses by TMA-specific first-order T suppressor factor

Energy Technology Data Exchange (ETDEWEB)

Jendrisak, G.S.; Bellone, C.J.

1986-03-05

The addition of hybridoma-derived phenyltrimethylammonium (TMA)-specific first-order T suppressor factor (TsF/sub 1/) into cultures containing Brucella abortus coupled with the TMA and trinitrophenol haptens (TMA-BA-TNP) results in the cross-suppression of TNP-specific plaque forming cell (PFC) responses. The suppression mediated by TMA-TsF/sub 1/ is dependent on the presence of T cells and specific antigen (TMA). Subculturing of whole spleen cells with TMA-TsF/sub 1/ and specific soluble antigen (TMA-BSA) is able to induce suppressor T cells which cross-suppress the TNP-specific PFC of spleen cell cultures stimulated with TMA-BA-TNP in an antigen (TMA)-dependent manner at the effector phase of the response. The effector acting T suppressor cells (Tse) are nylon wool nonadherent and appears to require whole spleen cells in responding cultures for suppression, suggesting that the target of the Tse is not the TNP-specific B cell. The authors are presently characterizing the mechanisms of cross-suppression by TMA-TsF/sub 1/ and Tse utilizing the described primary in vitro antibody assay.

Antioxidant Deactivation on Graphenic Nanocarbon Surfaces

Energy Technology Data Exchange (ETDEWEB)

Liu, Xinyuan [ORNL; Sen, Sujat [Brown University; Liu, Jingyu [Brown University; Kulaots, Indrek [Brown University; Geohegan, David B [ORNL; Kane, Agnes [Brown University; Puretzky, Alexander A [ORNL; Rouleau, Christopher M [ORNL; More, Karren Leslie [ORNL; Palmore, G. Tayhas R. [Brown University; Hurt, Robert H. [Brown University

2011-01-01

This article reports a direct chemical pathway for antioxidant deactivation on the surfaces of carbon nanomaterials. In the absence of cells, carbon nanotubes are shown to deplete the key physiological antioxidant glutathione (GSH) in a reaction involving dissolved dioxygen that yields the oxidized dimer, GSSG, as the primary product. In both chemical and electrochemical experiments, oxygen is only consumed at a significant steady-state rate in the presence of both nanotubes and GSH. GSH deactivation occurs for single- and multi-walled nanotubes, graphene oxide, nanohorns, and carbon black at varying rates that are characteristic of the material. The GSH depletion rates can be partially unified by surface area normalization, are accelerated by nitrogen doping, and suppressed by defect annealing or addition of proteins or surfactants. It is proposed that dioxygen reacts with active sites on graphenic carbon surfaces to produce surface-bound oxygen intermediates that react heterogeneously with glutathione to restore the carbon surface and complete a catalytic cycle. The direct catalytic reaction between nanomaterial surfaces and antioxidants may contribute to oxidative stress pathways in nanotoxicity, and the dependence on surface area and structural defects suggest strategies for safe material design.

Antioxidant mediated response of Scoparia dulcis in noise-induced redox imbalance and immunohistochemical changes in rat brain.

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Wankhar, Wankupar; Srinivasan, Sakthivel; Rajan, Ravindran; Sheeladevi, Rathinasamy

2017-01-19

Noise has been regarded as an environmental/occupational stressor that causes damages to both auditory and non-auditory organs. Prolonged exposure to these mediators of stress has often resulted in detrimental effect, where oxidative/nitrosative stress plays a major role. Hence, it would be appropriate to examine the possible role of free radicals in brain discrete regions and the "antioxidants" mediated response of S. dulcis. Animals were subjected to noise stress for 15 days (100 dB/4 hours/day) and estimation of endogenous free radical and antioxidant activity were carried out on brain discrete regions (the cerebral cortex, cerebellum, brainstem, striatum, hippocampus and hypothalamus). The result showed that exposure to noise could alleviate endogenous free radical generation and altered antioxidant status in brain discrete regions when compared to that of the control groups. This alleviated free radical generation (H 2 O 2 and NO) is well supported by an upregulated protein expression on immunohistochemistry of both iNOS and nNOS in the cerebral cortex on exposure to noise stress. These findings suggest that increased free radical generation and altered anti-oxidative status can cause redox imbalance in the brain discrete regions. However, free radical scavenging activity of the plant was evident as the noise exposed group treated with S. dulcis[200 mg/(kg·b·w)] displayed a therapeutic effect by decreasing the free radical level and regulate the anti-oxidative status to that of control animals. Hence, it can be concluded that the efficacy of S. dulcis could be attributed to its free radical scavenging activity and anti-oxidative property.

Effects of the amplitude and frequency of salinity fluctuations on antioxidant responses in juvenile tongue sole, Cynoglossus semilaevis

Energy Technology Data Exchange (ETDEWEB)

Khairnar, S.A.; Tian, X.; Dong, S.; Fang, Z.; Solanki, B.V.; Shanthanagouda, H.A.

2016-11-01

To understand the tolerance of tongue sole, Cynoglossus semilaevis, to varying salinities, the effects of the amplitude (2, 4, 6 and 8 g/L) and frequency (2, 4 and 8 days) of salinity fluctuations on the activities of antioxidant responses, including acidic phosphatase (ACP), alkaline phosphatase (AKP), catalase (CAT) and superoxide dismutase (SOD) from antioxidant system in liver, muscle, gills and kidney were investigated in this study. The results showed that the antioxidant responses of tongue sole were highly tissue-specific during the varying salinity fluctuations. In all tissues, ACP and AKP activity was found to be highest at moderate salinity fluctuations compared to the control, low and high salinity treatments (p<0.05). SOD and CAT activities had significant effect due to salinity fluctuations in all tissues (p<0.05), except in hepatic and renal tissues. Variations in branchial SOD activity proved that salinity fluctuations had greater impact on tongue sole at moderate and high fluctuating salinities compared to the control and low fluctuating salinities, whereas the branchial CAT activities showed contrasting trend. Further, cortisol levels were significantly affected in lower and higher salinity fluctuations. However, plasma cortisol levels remained low in moderate salinity fluctuations and control (p<0.05). Taken together, the results indicated that salinity fluctuations could effectively stimulate and enhance the antioxidant enzyme activity in the liver, kidney, gills and muscle of the juvenile tongue sole, thus effectively eliminating the excessive reactive oxygen species and minimizing the body damage in tongue sole or could be for any other euryhaline teleosts. (Author)

The Different Physiological and Antioxidative Responses of Zucchini and Cucumber to Sewage Sludge Application.

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Anna Wyrwicka

Full Text Available The present study investigates the effect of soil amended with sewage sludge on oxidative changes in zucchini and cucumber plants (Cucurbitaceae and the consequent activation of their antioxidative systems and detoxification mechanisms. The plants were grown in pots containing soil amended with three concentrations of sewage sludge (1.8 g, 5.4 g and 10.8 g per pot, while controls were potted with vegetable soil. The activities of three antioxidative enzymes, ascorbate peroxidase (APx, catalase (CAT and guaiacol peroxidase (POx, were assessed, as well as of the detoxifying enzyme S-glutathione transferase (GST. Lipid peroxidation was evaluated by measuring the extent of oxidative damage; α-tocopherol content, the main lipophilic antioxidant, was also measured. Visible symptoms of leaf blade damage after sewage sludge application occurred only on the zucchini plants. The zucchini and cucumber plants showed a range of enzymatic antioxidant responses to sewage sludge application. While APx and POx activities increased significantly with increasing sludge concentration in the zucchini plants, they decreased in the cucumber plants. Moreover, although the activity of these enzymes increased gradually with increasing doses of sewage sludge, these levels fell at the highest dose. An inverse relationship between peroxidases activity and CAT activity was observed in both investigated plant species. In contrast, although GST activity increased progressively with sludge concentration in both the zucchini and cucumber leaves, the increase in GST activity was greater in the zucchini plants, being visible at the lowest dose used. The results indicate that signs of sewage sludge toxicity were greater in zucchini than cucumber, and its defense reactions were mainly associated with increases in APx, POx and GST activity.

The Different Physiological and Antioxidative Responses of Zucchini and Cucumber to Sewage Sludge Application.

Science.gov (United States)

Wyrwicka, Anna; Urbaniak, Magdalena

2016-01-01

The present study investigates the effect of soil amended with sewage sludge on oxidative changes in zucchini and cucumber plants (Cucurbitaceae) and the consequent activation of their antioxidative systems and detoxification mechanisms. The plants were grown in pots containing soil amended with three concentrations of sewage sludge (1.8 g, 5.4 g and 10.8 g per pot), while controls were potted with vegetable soil. The activities of three antioxidative enzymes, ascorbate peroxidase (APx), catalase (CAT) and guaiacol peroxidase (POx), were assessed, as well as of the detoxifying enzyme S-glutathione transferase (GST). Lipid peroxidation was evaluated by measuring the extent of oxidative damage; α-tocopherol content, the main lipophilic antioxidant, was also measured. Visible symptoms of leaf blade damage after sewage sludge application occurred only on the zucchini plants. The zucchini and cucumber plants showed a range of enzymatic antioxidant responses to sewage sludge application. While APx and POx activities increased significantly with increasing sludge concentration in the zucchini plants, they decreased in the cucumber plants. Moreover, although the activity of these enzymes increased gradually with increasing doses of sewage sludge, these levels fell at the highest dose. An inverse relationship between peroxidases activity and CAT activity was observed in both investigated plant species. In contrast, although GST activity increased progressively with sludge concentration in both the zucchini and cucumber leaves, the increase in GST activity was greater in the zucchini plants, being visible at the lowest dose used. The results indicate that signs of sewage sludge toxicity were greater in zucchini than cucumber, and its defense reactions were mainly associated with increases in APx, POx and GST activity.

Optimization of ultrasonic assisted extraction of antioxidants from black soybean (Glycine max var) sprouts using response surface methodology.

Science.gov (United States)

Lai, Jixiang; Xin, Can; Zhao, Ya; Feng, Bing; He, Congfen; Dong, Yinmao; Fang, Yun; Wei, Shaomin

2013-01-16

Response surface methodology (RSM) using a central composite design (CCD) was employed to optimize the conditions for extraction of antioxidants from black soybean (Glycine max var) sprouts. Three influencing factors: liquid-solid ratio, period of ultrasonic assisted extraction and extraction temperature were investigated in the ultrasonic aqueous extraction. Then Response Surface Methodology (RSM) was applied to optimize the extraction process focused on DPPH radical-scavenging capacity of the antioxidants with respect to the above influencing factors. The best combination of each significant factor was determined by RSM design and optimum pretreatment conditions for maximum radical-scavenging capacity were established to be liquid-solid ratio of 29.19:1, extraction time of 32.13 min, and extraction temperature of 30 °C. Under these conditions, 67.60% of DPPH radical-scavenging capacity was observed experimentally, similar to the theoretical prediction of 66.36%.

Ethylene signaling renders the jasmonate response of Arabidopsis insensitive to future suppression by salicylic acid

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Leon Reyes, H.A.; Du, Y.; Koornneef, A.; Proietti, S.; Körbes, A.P.; Memelink, J.; Pieterse, C.M.J.; Ritsema, T.

2010-01-01

Cross-talk between jasmonate (JA), ethylene (ET), and Salicylic acid (SA) signaling is thought to operate as a mechanism to fine-tune induced defenses that are activated in response to multiple attackers. Here, 43 Arabidopsis genotypes impaired in hormone signaling or defense-related processes were screened for their ability to express SA-mediated suppression of JA-responsive gene expression. Mutant cev1, which displays constitutive expression of JA and ET responses, appeared to be insensitiv...

Differential Antioxidant Responses and Perturbed Porphyrin Biosynthesis after Exposure to Oxyfluorfen and Methyl Viologen in Oryza sativa

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Nhi-Thi Pham

2015-07-01

Full Text Available We compared antioxidant responses and regulation of porphyrin metabolism in rice plants treated with oxyfluorfen (OF or methyl viologen (MV. Plants treated with MV exhibited not only greater increases in conductivity and malondialdehyde but also a greater decline in Fv/Fm, compared to plants treated with OF. MV-treated plants had greater increases in activities of superoxide dismutase (SOD and catalase (CAT as well as transcript levels of SODA and CATA than OF-treated plants after 28 h of the treatments, whereas increases in ascorbate peroxidase (APX activity and transcript levels of APXA and APXB were greater in OF-treated plants. Both OF- and MV-treated plants resulted in not only down-regulation of most genes involved in porphyrin biosynthesis but also disappearance of Mg-porphyrins during the late stage of photooxidative stress. By contrast, up-regulation of heme oxygenase 2 (HO2 is possibly part of an efficient antioxidant response to compensate photooxidative damage in both treatments. Our data show that down-regulated biosynthesis and degradation dynamics of porphyrin intermediates have important roles in photoprotection of plants from perturbed porphyrin biosynthesis and photosynthetic electron transport. This study suggests that porphyrin scavenging as well as strong antioxidative activities are required for mitigating reactive oxygen species (ROS production under photooxidative stress caused by OF and MV.

LACK OF EFFECT OF AGE AND ANTIOXIDANT DEPLETION ON RESPIRATORY RESPONSES TO CONCENTRATED AMBIENT PARTICULATES (CAPS) IN RATS

Science.gov (United States)

2003 AAR PM MeetingParticulate Matter: Atmospheric Sciences,Exposure and the Fourth Colloquium on PM and Human HealthLACK OF EFFECT OF AGE AND ANTIOXIDANT DEPLETION ON RESPIRATORY RESPONSES TO CONCENTRATED AMBIENT PARTICULATES (CAPs) IN RATS. JA Dye, LC Walsh, C...

Antioxidant and Anti-Inflammatory Properties of Longan (Dimocarpus longan Lour. Pericarp

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Guan-Jhong Huang

2012-01-01

Full Text Available This study examined the antioxidant and anti-inflammatory activities of the water extract of longan pericarp (WLP. The results showed that WLP exhibited radical scavenging, reducing activity and liposome protection activity. In addition, WLP also inhibited lipopolysaccharide (LPS-induced nitric oxide (NO production in macrophages. Further, administration of WLP, in the range of 100–400 mg/kg, showed a concentration-dependent inhibition on paw edema development following carrageenan (Carr treatment in mice. The anti-inflammatory effects of WLP may be related to NO and tumor necrosis factor (TNF-α suppression and associated with the increase in the activities of antioxidant enzymes, including catalase, superoxide dismutase, and glutathione peroxidase. Overall, the results showed that WLP might serve as a natural antioxidant and inflammatory inhibitor.

Analysis of the effects of iron and vitamin C co-supplementation on oxidative damage, antioxidant response and inflammation in THP-1 macrophages.

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Marcil, V; Lavoie, J C; Emonnot, L; Seidman, E; Levy, E

2011-07-01

The aims of the study were to test the susceptibility of THP-1 macrophages to develop oxidative stress and to deploy antioxidant defense mechanisms that insure the balance between the pro- and antioxidant molecules. Differentiated THP-1 were incubated in the presence or absence of iron-ascorbate (Fe/As) (100/1000μM) and the antioxidants Trolox, BHT, α-Tocopherol and NAC. Fe/As promoted the production of lipid peroxidation as reflected by the formation of malondialdehyde and H(2)O(2) along with reduced PUFA levels and elevated glutathione disulfide/total glutathione ratio, a reliable index of cellular redox status. THP-1 macrophages developed an increase in cytoplasmic SOD activity due in part to high cytoplasmic SOD1. On the other hand, a decline was noted in mRNA and protein of extra-cellular SOD3, as well as the activity of GSH-peroxidase, GSH-transferase and ATOX-1 expression. Macrophages activated under conditions of oxidative stress do not adequately deploy a powerful endogenous antioxidant response, a situation that can lead to an enhanced inflammatory response. Copyright © 2011 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Targeting of the Glutathione, Thioredoxin, and Nrf2 Antioxidant Systems in Head and Neck Cancer.

Science.gov (United States)

Roh, Jong-Lyel; Jang, Hyejin; Kim, Eun Hye; Shin, Daiha

2017-07-10

The glutathione (GSH), thioredoxin (Trx), and Nrf2 systems represent a major defense against reactive oxygen species (ROS), the cellular imbalance of which in cancer promotes growth and therapeutic resistance. This study investigated whether targeting the GSH, Trx, and Nrf2 antioxidant systems effectively eliminated head and neck cancer (HNC). At high concentrations, auranofin, but not buthionine sulfoximine (BSO) alone, decreased the viability of HNC, whereas even at low concentrations, auranofin plus BSO synergized to kill HNC cells. Dual silencing of the genes for GCLM and TrxR1 induced GSH depletion, Trx activity inhibition, and ROS accumulation, synergistically killing HNC cells. Inhibition of the GSH and Trx systems resulted in activation of the Nrf2-antioxidant response element (ARE) pathway, which may result in suboptimal GSH and Trx inhibition where HNC is resistant. Genetic inhibition of Nrf2 and/or HO-1 or trigonelline enhanced growth suppression, ROS accumulation, and cell death from GSH and Trx inhibition. The in vivo effects of GSH, Trx, and Nrf2 system inhibition were confirmed in a mouse HNC xenograft model by achieving growth inhibition >60% compared with those of control. Innovations: This study is the first to show that triple inhibition of GSH, Trx, and Nrf2 pathways could be an effective method to overcome the resistance of HNC. Inhibition of the Nrf2-ARE pathway in addition to dual inhibition of the GSH and Trx antioxidant systems can effectively eliminate resistant HNC. Antioxid. Redox Signal. 27, 106-114.

Zinc-induced differential oxidative stress and antioxidant responses in Chlorella sorokiniana and Scenedesmus acuminatus.

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Hamed, Seham M; Zinta, Gaurav; Klöck, Gerd; Asard, Han; Selim, Samy; AbdElgawad, Hamada

2017-06-01

Algae are frequently exposed to toxic metals, and zinc (Zn) is one of the major toxicants present. We exposed two green microalgae, Chlorella sorokiniana and Scenedesmus acuminatus, to sub-lethal concentrations (1.0 and 0.6mM) of Zn for seven days. Algal responses were analysed at the level of growth, oxidative stress, and antioxidants. Growth parameters such as cell culture yield and pigment content were less affected by Zn in C. sorokiniana, despite the fact that this alga accumulated more zinc than S. acuminatus. Also, C. sorokiniana, but not S. acuminatus, was able to acclimatize during long-term exposure to toxic concentrations of the test metals (specific growth rate (µ) was 0.041/day and total chlorophyll was 14.6mg/mL). Although, Zn induced oxidative stress in both species, C. sorokiniana experienced less stress than S. acuminatus. This could be explained by a higher accumulation of antioxidants in C. sorokiniana, where flavonoids, polyphenols, tocopherols, glutathione (GSH) and ascorbate (ASC) content increased. Moreover, antioxidant enzymes glutathione S transferase (GST), glutathione reductase (GR), superoxide dismutase (SOD), peroxidase (POX) and ascorbate peroxidase (APX), showed increased activities in C. sorokiniana. In addition to, and probably also underlying, the higher Zn tolerance in C. sorokiniana, this alga also showed higher Zn biosorption capacity. Use of C. sorokiniana as a bio-remediator, could be considered. Copyright © 2017 Elsevier Inc. All rights reserved.

Auditory-visual integration modulates location-specific repetition suppression of auditory responses.

Science.gov (United States)

Shrem, Talia; Murray, Micah M; Deouell, Leon Y

2017-11-01

Space is a dimension shared by different modalities, but at what stage spatial encoding is affected by multisensory processes is unclear. Early studies observed attenuation of N1/P2 auditory evoked responses following repetition of sounds from the same location. Here, we asked whether this effect is modulated by audiovisual interactions. In two experiments, using a repetition-suppression paradigm, we presented pairs of tones in free field, where the test stimulus was a tone presented at a fixed lateral location. Experiment 1 established a neural index of auditory spatial sensitivity, by comparing the degree of attenuation of the response to test stimuli when they were preceded by an adapter sound at the same location versus 30° or 60° away. We found that the degree of attenuation at the P2 latency was inversely related to the spatial distance between the test stimulus and the adapter stimulus. In Experiment 2, the adapter stimulus was a tone presented from the same location or a more medial location than the test stimulus. The adapter stimulus was accompanied by a simultaneous flash displayed orthogonally from one of the two locations. Sound-flash incongruence reduced accuracy in a same-different location discrimination task (i.e., the ventriloquism effect) and reduced the location-specific repetition-suppression at the P2 latency. Importantly, this multisensory effect included topographic modulations, indicative of changes in the relative contribution of underlying sources across conditions. Our findings suggest that the auditory response at the P2 latency is affected by spatially selective brain activity, which is affected crossmodally by visual information. © 2017 Society for Psychophysiological Research.

Bifidobacterium breve prevents necrotising enterocolitis by suppressing inflammatory responses in a preterm rat model.

Science.gov (United States)

Satoh, T; Izumi, H; Iwabuchi, N; Odamaki, T; Namba, K; Abe, F; Xiao, J Z

2016-02-01

Necrotising enterocolitis (NEC) is associated with inflammatory responses and barrier dysfunction in the gut. In this study, we investigated the effect of Bifidobacterium breve M-16V on factors related to NEC development using an experimental rat model. Caesarean-sectioned rats were given formula milk with or without B. breve M-16V by oral gavage thrice daily, and experimental NEC was induced by exposing the rats to hypoxic conditions. Naturally delivered rats that were reared by their mother were used as healthy controls. The pathological score of NEC and the expression of molecules related to inflammatory responses and the barrier function were assessed in the ileum. B. breve M-16V reduced the pathological scores of NEC and resulted in some improvement in survivability. B. breve M-16V suppressed the increased expression of molecules related to inflammation and barrier function that resulted from NEC induction. B. breve M-16V normalised Toll-like receptor (TRL)4 expression and enhanced TLR2 expression. Our data suggest that B. breve M-16V prevents NEC development by modulating TLR expressions and suppressing inflammatory responses in a rat model.

The effects of the painkiller diclofenac and hypoxia on gene transcription and antioxidant system in the gills of three-spined stickleback.

Science.gov (United States)

Lubiana, Pedro; Prokkola, Jenni M; Nikinmaa, Mikko; Burmester, Thorsten; Kanerva, Mirella; Götting, Miriam

2016-01-01

Aquatic organisms face multiple stressors in natural ecosystems. More and more often painkillers are detected in surface waters since their prescription has increased worldwide within the last years. Here we examined the effects of the non-steroidal anti-inflammatory drug (NSAID) diclofenac and hypoxia on three-spined sticklebacks (Gasterosteus aculeatus). We exposed sticklebacks to an environmentally relevant concentration of diclofenac (1μg/L) for 14days, to 24h of hypoxia (2.0mg O2/L), and a combination of both. Hypoxia and diclofenac both can be associated with oxidative stress in fish, but it is unclear whether they would act synergistically. Expression analysis of genes related to antioxidant response, hypoxia response, and chemical metabolism in gills showed that diclofenac alone had little effect, while the combination of hypoxia and diclofenac affected transcript levels most, indicating synergistic effects of these stressors. Of the antioxidant enzymes, only superoxide dismutase activity remained unchanged by treatments, while glutathione peroxidase (GPx) was the most affected antioxidant response on both the transcript and activity levels. Our results suggest that diclofenac may lead to suppressed catalase (CAT) activity but increased GPx activity, probably as compensatory mechanism to remove increasing H2O2 in the gills, and that this response is not affected by hypoxia. The activities of lactate dehydrogenase, CAT, and GPx also showed temporal variability during treatments, which can be attributable to tissue-specific circadian rhythms. Our study shows how responses to NSAIDs and hypoxia can interact in fish, suggesting that getting more insight into temporal variation and about the different levels of regulation of environmental responses is necessary in future studies. Copyright © 2016. Published by Elsevier Inc.

Exercise, oxidants, and antioxidants change the shape of the bell-shaped hormesis curve

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Zsolt Radak

2017-08-01

Full Text Available It is debated whether exercise-induced ROS production is obligatory to cause adaptive response. It is also claimed that antioxidant treatment could eliminate the adaptive response, which appears to be systemic and reportedly reduces the incidence of a wide range of diseases. Here we suggest that if the antioxidant treatment occurs before the physiological function-ROS dose-response curve reaches peak level, the antioxidants can attenuate function. On the other hand, if the antioxidant treatment takes place after the summit of the bell-shaped dose response curve, antioxidant treatment would have beneficial effects on function. We suggest that the effects of antioxidant treatment are dependent on the intensity of exercise, since the adaptive response, which is multi pathway dependent, is strongly influenced by exercise intensity. It is further suggested that levels of ROS concentration are associated with peak physiological function and can be extended by physical fitness level and this could be the basis for exercise pre-conditioning. Physical inactivity, aging or pathological disorders increase the sensitivity to oxidative stress by altering the bell-shaped dose response curve.

The proper time for antioxidant consumption.

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Beaulieu, Michaël; Schaefer, H Martin

2014-04-10

Consuming food rich in antioxidants may help organisms to increase their antioxidant defences and avoid oxidative damage. Under the hypothesis that organisms actively consume food for its antioxidant properties, they would need to do so in view of other physiological requirements, such as energy requirements. Here, we observed that Gouldian finches (Erythrura gouldiae) consumed most seeds rich in antioxidants in the middle of the day, while their consumption of staple seeds more profitable in energy intake (and poor in antioxidants) was maximal in the morning and the evening. This consumption of seeds rich in antioxidants in the middle of the day may be explicable (1) because birds took advantage of a time window associated with relaxed energy requirements to ingest antioxidant resources, or (2) because birds consumed antioxidant resources as a response to the highest antioxidant requirements in the middle of the day. If the latter hypothesis holds true, having the possibility to ingest antioxidants should be most beneficial in terms of oxidative balance in the middle of the day. Even though feeding on seeds rich in antioxidants improved Gouldian finches' overall antioxidant capacity, we did not detect any diurnal effect of antioxidant intake on plasma oxidative markers (as measured by the d-ROM and the OXY-adsorbent tests). This indicates that the diurnal pattern of antioxidant intake that we observed was most likely constrained by the high consumption of staple food to replenish or build up body reserves in the morning and in the evening, and not primarily determined by elevated antioxidant requirements in the middle of the day. Consequently, animals appear to have the possibility to increase antioxidant defences by selecting food rich in antioxidants, only when energetic constraints are relaxed. Copyright © 2014 Elsevier Inc. All rights reserved.

Anti-oxidant activity and attenuation of bladder hyperactivity by the flavonoid compound kaempferol.

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Huang, Yaw-Bin; Lin, Ming-Wei; Chao, Yun; Huang, Chi-Te; Tsai, Yi-Hung; Wu, Pao-Chu

2014-01-01

To evaluate the anti-oxidant activity of the flavonoid compound, kaempferol, and to examine its role in the suppression of oxidative stress and attenuation of bladder hyperactivity in a rat model of bladder injury. The anti-oxidative activity of kaempferol was examined in lipopolysaccharide-treated RAW264.7 macrophages by using flow cytometry. For in vivo studies, rats were pretreated with kaempferol or vehicle for 24 h. The rat urothelium was injured by the administration of protamine sulfate for 1.5 h and irritated by the subsequent infusion of potassium chloride for 4 h. Oxidative stress in the bladder tissue was assessed using chemiluminescence assay, and the bladder pressure was determination by cystomertrogram. Kaempferol significantly suppressed lipopolysaccharide-induced reactive oxygen species production in RAW264.7 rat macrophages. Exposure of the rat bladder to sequential infusion of protamine sulfate and potassium chloride induced bladder hyperactivity. Pretreatment with kaempferol, prevented the formation of reactive oxygen species and prolonged the intercontraction interval. Kaempferol suppresses oxidative stress and attenuates bladder hyperactivity caused by potassium chloride after protamine sulfate-induced bladder injury. © 2013 The Japanese Urological Association.

ITE Suppresses Angiogenic Responses in Human Artery and Vein Endothelial Cells: Differential Roles of AhR.

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Li, Yan; Wang, Kai; Zou, Qing-Yun; Jiang, Yi-Zhou; Zhou, Chi; Zheng, Jing

2017-12-01

Aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor is involved in regulation of many essential biological processes including vascular development and angiogenesis. 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) is an AhR ligand, which regulates immune responses and cancer cell growth. However, the roles of the ITE/AhR pathway in mediating placental angiogenesis remains elusive. Here, we determined if ITE affected placental angiogenic responses via AhR in human umbilical vein (HUVECs) and artery endothelial (HUAECs) cells in vitro. We observed that ITE dose- and time-dependently inhibited proliferation and viability of HUAECs and HUVECs, whereas it inhibited migration of HUAECs, but not HUVECs. While AhR siRNA significantly suppressed AhR protein expression in HUVECs and HUAECs, it attenuated the ITE-inhibited angiogenic responses of HUAECs, but not HUVECs. Collectively, ITE suppressed angiogenic responses of HUAECs and HUVECs, dependent and independent of AhR, respectively. These data suggest that ITE may regulate placental angiogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

Anchoring novel molecular biomarker responses to traditional responses in fish exposed to environmental contamination

International Nuclear Information System (INIS)

Nogueira, Patricia; Pacheco, Mario; Lourdes Pereira, M.; Mendo, Sonia; Rotchell, Jeanette M.

2010-01-01

The responses of Dicentrarchus labrax and Liza aurata to aquatic pollution were assessed in a contaminated coastal lagoon, using both traditional and novel biomarkers combined. DNA damage, assessed by comet assay, was higher in both fish species from the contaminated sites, whereas levels of cytochrome P450 1A1 gene expression were not significantly altered. The liver histopathological analysis also revealed significant lesions in fish from contaminated sites. Alterations in ras and xpf genes were analysed and additional pollutant-responsive genes were identified. While no alterations were found in ras gene, a downregulation of xpf gene was observed in D. labrax from a contaminated site. Suppression subtractive hybridization applied to D. labrax collected at a contaminated site, revealed altered expression in genes involved in energy metabolism, immune system activity and antioxidant response. The approach and results reported herein demonstrate the utility of anchoring traditional biomarker responses alongside novel biomarker responses. - Novel molecular biomarkers of aquatic environmental contamination in fish.

Suppression of a Natural Killer Cell Response by Simian Immunodeficiency Virus Peptides.

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Jamie L Schafer

2015-09-01

Full Text Available Natural killer (NK cell responses in primates are regulated in part through interactions between two highly polymorphic molecules, the killer-cell immunoglobulin-like receptors (KIRs on NK cells and their major histocompatibility complex (MHC class I ligands on target cells. We previously reported that the binding of a common MHC class I molecule in the rhesus macaque, Mamu-A1*002, to the inhibitory receptor Mamu-KIR3DL05 is stabilized by certain simian immunodeficiency virus (SIV peptides, but not by others. Here we investigated the functional implications of these interactions by testing SIV peptides bound by Mamu-A1*002 for the ability to modulate Mamu-KIR3DL05+ NK cell responses. Twenty-eight of 75 SIV peptides bound by Mamu-A1*002 suppressed the cytolytic activity of primary Mamu-KIR3DL05+ NK cells, including three immunodominant CD8+ T cell epitopes previously shown to stabilize Mamu-A1*002 tetramer binding to Mamu-KIR3DL05. Substitutions at C-terminal positions changed inhibitory peptides into disinhibitory peptides, and vice versa, without altering binding to Mamu-A1*002. The functional effects of these peptide variants on NK cell responses also corresponded to their effects on Mamu-A1*002 tetramer binding to Mamu-KIR3DL05. In assays with mixtures of inhibitory and disinhibitory peptides, low concentrations of inhibitory peptides dominated to suppress NK cell responses. Consistent with the inhibition of Mamu-KIR3DL05+ NK cells by viral epitopes presented by Mamu-A1*002, SIV replication was significantly higher in Mamu-A1*002+ CD4+ lymphocytes co-cultured with Mamu-KIR3DL05+ NK cells than with Mamu-KIR3DL05- NK cells. These results demonstrate that viral peptides can differentially affect NK cell responses by modulating MHC class I interactions with inhibitory KIRs, and provide a mechanism by which immunodeficiency viruses may evade NK cell responses.

Oxytocin and prolactin suppress cortisol responses to acute stress in both lactating and non-lactating sheep.

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Cook, C J

1997-08-01

Cortisol response to stress appears to differ between lactating and non-lactating animals. Lactating (14 d post partum) and non-lactating sheep were fitted with probes so that drugs and hormones could be infused directly into the posterior pituitary and paraventricular nucleus of the hypothalamus. The animals were also fitted with instruments to allow monitoring of heart rate, body temperature and blood cortisol levels. Their reactions to a source of acute stress (a barking dog) were then followed, with or without drug and hormone manipulation. Results in both lactating and non-lactating animals indicated shortcomings in the use of cortisol as a stress indicator. Infusing prolactin and oxytocin into either the posterior pituitary or the paraventricular nucleus of the hypothalamus suppressed cortisol responsiveness to stress in both lactating and non-lactating animals (the latter to a greater extent). In the absence of drugs, lactating animals had a slightly higher basal level of cortisol and a lower cortisol response to stress than their non-lactating counterparts. Despite suppression of cortisol responses, with or without drugs, other indicators of stress still changed with the presence of a barking dog, suggesting the complexity of control involved in stress responses.

Nrf2, the Master Regulator of Anti-Oxidative Responses

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Sandra Vomund

2017-12-01

Full Text Available Tight regulation of inflammation is very important to guarantee a balanced immune response without developing chronic inflammation. One of the major mediators of the resolution of inflammation is the transcription factor: the nuclear factor erythroid 2-like 2 (Nrf2. Stabilized following oxidative stress, Nrf2 induces the expression of antioxidants as well as cytoprotective genes, which provoke an anti-inflammatory expression profile, and is crucial for the initiation of healing. In view of this fundamental modulatory role, it is clear that both hyper- or hypoactivation of Nrf2 contribute to the onset of chronic diseases. Understanding the tight regulation of Nrf2 expression/activation and its interaction with signaling pathways, known to affect inflammatory processes, will facilitate development of therapeutic approaches to prevent Nrf2 dysregulation and ameliorate chronic inflammatory diseases. We discuss in this review the principle mechanisms of Nrf2 regulation with a focus on inflammation and autophagy, extending the role of dysregulated Nrf2 to chronic diseases and tumor development.

[Responses of antioxidation system of Cynodon dactylon to recirculated landfill leachate irrigation].

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Wang, Ruyi; He, Pinjing; Shao, Liming; Zhang, Bin; Li, Guojian

2005-05-01

With pot experiment, this paper studied the membrane lipid peroxidation and the variations of antioxidation system in Cynodon dactylon under recirculated landfill leachate irrigation. The results showed that when irrigated with low dilution ratio ( 25%), there existed an obvious negative fect on Cynodon dactylon, i.e., the chlorophyll a/b ratio decreased, while cell membrane permeability and MDA and H2O2 contents increased, which meant that the membrane lipid peroxidation was accelerated. The contents antioxidants AsA, GSH and Car also showed the similar trend, i.e., they increased with increasing leachate dilution ratio when irrigated with low dilution ratio leachate, but decreased under medium or high dilution ratio leachate irrigation. Among three test anti-oxidative enzymes, SOD and POD activities showed a similar change test antioxidants, and POD activity was more sensitive, while CAT activity was on the contrary. The contents test antioxidants and the activities of SOD and POD were negatively and significantly correlated to MDA content, indicating that they might play an important role in preventing Cynodon dactylon from cell membrane lipid peroxdation.

Id1 suppresses anti-tumour immune responses and promotes tumour progression by impairing myeloid cell maturation.

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Papaspyridonos, Marianna; Matei, Irina; Huang, Yujie; do Rosario Andre, Maria; Brazier-Mitouart, Helene; Waite, Janelle C; Chan, April S; Kalter, Julie; Ramos, Ilyssa; Wu, Qi; Williams, Caitlin; Wolchok, Jedd D; Chapman, Paul B; Peinado, Hector; Anandasabapathy, Niroshana; Ocean, Allyson J; Kaplan, Rosandra N; Greenfield, Jeffrey P; Bromberg, Jacqueline; Skokos, Dimitris; Lyden, David

2015-04-29

A central mechanism of tumour progression and metastasis involves the generation of an immunosuppressive 'macroenvironment' mediated in part through tumour-secreted factors. Here we demonstrate that upregulation of the Inhibitor of Differentiation 1 (Id1), in response to tumour-derived factors, such as TGFβ, is responsible for the switch from dendritic cell (DC) differentiation to myeloid-derived suppressor cell expansion during tumour progression. Genetic inactivation of Id1 largely corrects the myeloid imbalance, whereas Id1 overexpression in the absence of tumour-derived factors re-creates it. Id1 overexpression leads to systemic immunosuppression by downregulation of key molecules involved in DC differentiation and suppression of CD8 T-cell proliferation, thus promoting primary tumour growth and metastatic progression. Furthermore, advanced melanoma patients have increased plasma TGFβ levels and express higher levels of ID1 in myeloid peripheral blood cells. This study reveals a critical role for Id1 in suppressing the anti-tumour immune response during tumour progression and metastasis.

Suppression of humoral response during the course of Candida albicans infection in mice.

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Valdez, J C; Meson, O E; de Valdez, G A; Sirena, A

1984-10-30

This paper aims at demonstrating the non-specific immunosuppression as regards thyme-dependent antigens sheep erythrocytes (SRBC) during the course of Candida albicans systemic infection. Three lots of syngeneic/BALB/c mice, 8-12 weeks of age, were used. The first normal lot was inoculated via the intraperitoneal route with a (SRBC) suspension (4 X 10(8) cells ml) in a Hank's balanced saline solution. The primary response of antibodies formed by splenic cells was measured from 4 to 8 days after inoculation using the direct plaque forming cells technique. The second lot was infected by the same route with a suspension of Candida albicans (1 X 10(7) cells). Positive retrocultures from the blood and kidneys of these infected mice were obtained. These yeasts cultivated in a Sabouraud medium were harvested after 20 h at 37 degrees C. Following the same methodology the immune response to SRBC was determined. The serum obtained from infected mice was transferred to a third lot of mice at different intervals during the course of the infection. The immune response to SRBC was done by the direct plaque-forming cells technique. Controls were carried out using normal donors and recipients. A suppression of the immune response was obtained as from the 2nd day of inoculation up to the 28th day. It was not possible to transfer such suppression passively by means of the serum. These results suggest that the systemic infection by Candida albicans induce a non-specific immunosuppression in the organism, already demonstrated in viral infections, bacteria, protozoaria and metazoaria in mammals. In some way, this will contribute to explain the mechanisms of immune response to Candida albicans.

Synthesis, antihyperglycemic activity and computational studies of antioxidant chalcones and flavanones derived from 2,5 dihydroxyacetophenone

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Tajammal, Affifa; Batool, Majda; Ramzan, Ayesha; Samra, Malka M.; Mahnoor, Idrees; Verpoort, Francis; Irfan, Ahmad; Al-Sehemi, Abdullah G.; Munawar, Munawar Ali; Basra, Muhammad Asim R.

2017-11-01

Chronic exposure of supraphysiologic glucose concentration to cells and tissues resulted in glucose toxicity which causes oxidative stress. Antioxidants have promising effect in suppressing the oxidative stress in the pathogenesis of diabetes mellitus (DM). Condensation of 2,5-dihydroxyacetophenone with different nitrobenzaldehydes was used to synthesize antioxidant nitro substituted chalcones along with nitro substituted flavanones in one step protocol. The compounds were characterized by IR, 1H NMR and 13C NMR and then screened for their in vitro antioxidant and in vivo antihyperglycemic activities. Postulated structures of the synthesized compounds were in agreement with their spectral data. The results indicated that the novel compound (2E)-1-(2,5-Dihydroxyphenyl)-3-(2-nitrophenyl) prop-2-en-1-one (2a) was potent antioxidant because of its lower IC50 value compared with trolox and ascorbic acid. Compound 2a also exhibited excellent antihyperglycemic activity in diabetic rats while the compound (E)-1-(2,5-Dihydroxyphenyl)-3-(4-nitrophenyl)prop-2-one (2c) suppressed the hyperglycemia more effectively in normal rats. The radical scavenging activity behavior was elucidated on the basis of hydrogen atom transfer and one-electron transfer mechanisms by density functional theory (DFT). The compound 2a showed the smallest ionization potential and bond dissociation enthalpy. Experimental and computational investigations concluded that compound 2a might be an effective antihyperglycemic agent because of its antioxidative nature and smallest ionization potential.

Antioxidant and Anti-Osteoporosis Activities of Chemical Constituents of the Stems of Zanthoxylum piperitum.

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Yang, Seo Young; Lee, Sang-Hyun; Tai, Bui Huu; Jang, Hae-Dong; Kim, Young Ho

2018-02-18

Two new lignans, zanthoxyloside C ( 1 ) and zanthoxyloside D ( 2 ), together with nine known compounds comprising lignans ( 3 - 5 ), flavonoids ( 6 - 8 ), and phenolics ( 9 - 11 ), were isolated from the methanol extract of the stems of Zanthoxylum piperitum. All isolates were evaluated for their antioxidant and anti-osteoporotic activities using oxygen radical absorbance capacity (ORAC), cupric reducing antioxidant capacity (CUPRAC), and tartrate-resistant acid phosphatase (TRAP) assays. Compounds 7 - 10 showed peroxyl radical-scavenging capacities and 4 , 6 - 7 , and 9 showed reducing capacities. Moreover, compounds 3 , 6 - 9 , and 11 significantly suppressed TRAP activities. These results indicated that the stems of Z. piperitum could be an excellent source for natural antioxidant and anti-osteoporosis.

Limiting immunopathology: Interaction between carotenoids and enzymatic antioxidant defences.

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Babin, A; Saciat, C; Teixeira, M; Troussard, J-P; Motreuil, S; Moreau, J; Moret, Y

2015-04-01

The release of reactive oxygen and nitrogen species (ROS and RNS) during the inflammatory response generates damages to host tissues, referred to as immunopathology, and is an important factor in ecological immunology. The integrated antioxidant system, comprising endogenous antioxidant enzymes (e.g. superoxide dismutase SOD, and catalase CAT) and dietary antioxidants (e.g. carotenoids), helps to cope with immune-mediated oxidative stress. Crustaceans store large amounts of dietary carotenoids for yet unclear reasons. While being immunostimulants and antioxidants, the interaction of these pigments with antioxidant enzymes remains unclear. Here, we tested the interaction between dietary supplementation with carotenoids and immune challenge on immune defences and the activity of the antioxidant enzymes SOD and CAT, in the amphipod crustacean Gammarus pulex. Dietary supplementation increased the concentrations of circulating carotenoids and haemocytes in the haemolymph, while the immune response induced the consumption of circulating carotenoids and a drop of haemocyte density. Interestingly, supplemented gammarids exhibited down-regulated SOD activity but high CAT activity compared to control ones. Our study reveals specific interactions of dietary carotenoids with endogenous antioxidant enzymes, and further underlines the potential importance of carotenoids in the evolution of immunity and/or of antioxidant mechanisms in crustaceans. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chronic exposure to dim light at night suppresses immune responses in Siberian hamsters.

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Bedrosian, Tracy A; Fonken, Laura K; Walton, James C; Nelson, Randy J

2011-06-23

Species have been adapted to specific niches optimizing survival and reproduction; however, urbanization by humans has dramatically altered natural habitats. Artificial light at night (LAN), termed 'light pollution', is an often overlooked, yet increasing disruptor of habitats, which perturbs physiological processes that rely on precise light information. For example, LAN alters the timing of reproduction and activity in some species, which decreases the odds of successful breeding and increases the threat of predation for these individuals, leading to reduced fitness. LAN also suppresses immune function, an important proxy for survival. To investigate the impact of LAN in a species naive to light pollution in its native habitat, immune function was examined in Siberian hamsters derived from wild-caught stock. After four weeks exposure to dim LAN, immune responses to three different challenges were assessed: (i) delayed-type hypersensitivity (DTH), (ii) lipopolysaccharide-induced fever, and (iii) bactericide activity of blood. LAN suppressed DTH response and reduced bactericide activity of blood after lipopolysaccharide treatment, in addition to altering daily patterns of locomotor activity, suggesting that human encroachment on habitats via night-time lighting may inadvertently compromise immune function and ultimately fitness.

Optimization of the Extraction of Antioxidants and Caffeine from Maté (Ilex paraguariensis Leaves by Response Surface Methodology

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Vanessa Graciela Hartwig

2013-04-01

Full Text Available Optimal conditions for the industrial extraction of total polyphenols from maté (Ilex paraguariensis were determined using response surface methodology, with two independent variables: ethanol percentage of the extraction solution and liquid to solid ratio. Response variables were total polyphenol content, antioxidant capacity, concentration of total polyphenols and caffeine content. The optimal conditions found were a liquid to solid ratio from 8 - 9 w w-1 and ethanol percentage of the extraction solution from 30 -50 % w w-1. Under these conditions the main predicted values corresponding to leaf extracts were 40 μg chlorogenic acid equivalents mL-1 of original extract, 13 g chlorogenic acid equivalents per 100 g dry matter for total polyphenol content, 22 g Trolox equivalents and 15.5 g ascorbic acid equivalents per 100 g dry matter for antioxidant capacity. The total polyphenol content of twig extracts was 36% lower than that in the leaf extracts.

Co-loading and intestine-specific delivery of multiple antioxidants in pH-responsive microspheres based on TEMPO-oxidized polysaccharides

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Shi, Mengxuan; Bai, Jie; Zhao, Liyun; Yu, Xinrui; Liang, Jingjing; Liu, Ying; Norde, Willem; Li, Yuan

2017-01-01

In this study, pH-responsive microspheres loaded with multiple antioxidants were developed for intestine-specific delivery and exhibited synergistic activity. They consist of chitosan (CS)-coated microspheres made of TEMPO-oxidized Konjac glucomannan (OKGM) polymers, of which the carboxyl (COO−)

Ultrasound-Assisted Extraction of Total Flavonoids from Corn Silk and Their Antioxidant Activity

OpenAIRE

Zheng, Ling-Li; Wen, Guan; Yuan, Min-Yong; Gao, Feng

2016-01-01

Object. Ultrasound-assisted extraction of total flavonoids from corn silk and their antioxidant activities were studied. Methods. Response surface methodology was adopted to optimize the extraction conditions and antioxidant activities of the extracted total flavonoids were detected through ferric reducing antioxidant power (FRAP) assay. Results. Through a three-level, three-variable Box-Behnken design of response surface methodology (RSM) adopting yield as response, the optimal conditions we...

Suppression of Antitumor Immune Responses by Human Papillomavirus through Epigenetic Downregulation of CXCL14

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Louis Cicchini

2016-05-01

Full Text Available High-risk human papillomaviruses (HPVs are causally associated with multiple human cancers. Previous studies have shown that the HPV oncoprotein E7 induces immune suppression; however, the underlying mechanisms remain unknown. To understand the mechanisms by which HPV deregulates host immune responses in the tumor microenvironment, we analyzed gene expression changes of all known chemokines and their receptors using our global gene expression data sets from human HPV-positive and -negative head/neck cancer and cervical tissue specimens in different disease stages. We report that, while many proinflammatory chemokines increase expression throughout cancer progression, CXCL14 is dramatically downregulated in HPV-positive cancers. HPV suppression of CXCL14 is dependent on E7 and associated with DNA hypermethylation in the CXCL14 promoter. Using in vivo mouse models, we revealed that restoration of Cxcl14 expression in HPV-positive mouse oropharyngeal carcinoma cells clears tumors in immunocompetent syngeneic mice, but not in Rag1-deficient mice. Further, Cxcl14 reexpression significantly increases natural killer (NK, CD4+ T, and CD8+ T cell infiltration into the tumor-draining lymph nodes in vivo. In vitro transwell migration assays show that Cxcl14 reexpression induces chemotaxis of NK, CD4+ T, and CD8+ T cells. These results suggest that CXCL14 downregulation by HPV plays an important role in suppression of antitumor immune responses. Our findings provide a new mechanistic understanding of virus-induced immune evasion that contributes to cancer progression.

Antioxidant response of ridgetail white prawn Exopalaemon carinicauda to harmful dinoflagellate Prorocentrum minimum exposure and its histological change

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Mu, Cuimin; Ren, Xianyun; Ge, Qianqian; Wang, Jiajia; Li, Jian

2017-04-01

The dinoflagellate Prorocentrum minimum, one of the most widespread red tide causing species, affects marine aquaculture and ecosystems worldwide. In this study, ridgetail white prawn Exopalaemon carinicauda were exposed to P. minimum cells (5 × 104 cells mL-1) to investigate its harmful effects on the shrimp. Antioxidant activities and histological changes were used as indicators of health status of the shrimp. In 72 hours, the mortality of E. carinicauda was not affected, but its antioxidant response and histology were statistically different from those of control. Elevated superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities and depressed catalase (CAT) activity were observed in gill; while increased SOD, glutathione S-transferase (GST), CAT activities and modulated GPX activity were observed in hepatopancreas. Thus, antioxidant activities in gill and hepatopancreas seem to respond differentially to harmful alga exposure. Increased malondialdehyde (MDA) content in early a few hours indicates the damage of the antioxidant defense system. Although MDA content recovered to a low level thereafter, a series of histological abnormalities including accumulation or infiltration of hemocytes, tissue lesions and necrosis were discovered in gill and hepatopancreas. Exposure to P. minimum induced sublethal effects on E. carinicauda, including temporary oxidative damage and histological injury.

Effects of Heat Shock on Photosynthetic Properties, Antioxidant Enzyme Activity, and Downy Mildew of Cucumber (Cucumis sativus L..

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Xiaotao Ding

Full Text Available Heat shock is considered an abiotic stress for plant growth, but the effects of heat shock on physiological responses of cucumber plant leaves with and without downy mildew disease are still not clear. In this study, cucumber seedlings were exposed to heat shock in greenhouses, and the responses of photosynthetic properties, carbohydrate metabolism, antioxidant enzyme activity, osmolytes, and disease severity index of leaves with or without the downy mildew disease were measured. Results showed that heat shock significantly decreased the net photosynthetic rate, actual photochemical efficiency, photochemical quenching coefficient, and starch content. Heat shock caused an increase in the stomatal conductance, transpiration rate, antioxidant enzyme activities, total soluble sugar content, sucrose content, soluble protein content and proline content for both healthy leaves and downy mildew infected leaves. These results demonstrate that heat shock activated the transpiration pathway to protect the photosystem from damage due to excess energy in cucumber leaves. Potential resistance mechanisms of plants exposed to heat stress may involve higher osmotic regulation capacity related to an increase of total accumulations of soluble sugar, proline and soluble protein, as well as higher antioxidant enzymes activity in stressed leaves. Heat shock reduced downy mildew disease severity index by more than 50%, and clearly alleviated downy mildew development in the greenhouses. These findings indicate that cucumber may have a complex physiological change to resist short-term heat shock, and suppress the development of the downy mildew disease.

Optimization extraction conditions for improving phenolic content and antioxidant activity in Berberis asiatica fruits using response surface methodology (RSM).

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Belwal, Tarun; Dhyani, Praveen; Bhatt, Indra D; Rawal, Ranbeer Singh; Pande, Veena

2016-09-15

This study for the first time designed to optimize the extraction of phenolic compounds and antioxidant potential of Berberis asiatica fruits using response surface methodology (RSM). Solvent selection was done based on the preliminary experiments and a five-factors-three-level, Central Composite Design (CCD). Extraction temperature (X1), sample to solvent ratio (X3) and solvent concentration (X5) significantly affect response variables. The quadratic model well fitted for all the responses. Under optimal extraction conditions, the dried fruit sample mixed with 80% methanol having 3.0 pH in a ratio of 1:50 and the mixture was heated at 80 °C for 30 min; the measured parameters was found in accordance with the predicted values. High Performance Liquid Chromatography (HPLC) analysis at optimized condition reveals 6 phenolic compounds. The results suggest that optimization of the extraction conditions is critical for accurate quantification of phenolics and antioxidants in Berberis asiatica fruits, which may further be utilized for industrial extraction procedure. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electrochemical study of the increased antioxidant capacity of flavonoids through complexation with iron(II) ions

International Nuclear Information System (INIS)

Porfírio, Demóstenes Amorim; Ferreira, Rafael de Queiroz; Malagutti, Andréa Renata; Valle, Eliana Maíra Agostini

2014-01-01

Highlights: • Metal-Flavonoid complexes exhibit greater antioxidant capacity than the free flavonoid;. • Voltammetric profile is an additional information for determining antioxidant capacity;. • Pyrogallol group is a stronger complex-forming group than the catechol;. • Morin, quercetin and fisetin increased their antioxidant capacity in 15%, 32% and 28%, respectively. - Abstract: Flavonoids are polyphenolic compounds that act as natural antioxidants in the human body through various mechanisms, with an emphasis on suppressing reactive oxygen species (ROS) formation by inhibiting enzymes, the direct capture of ROS, and the regulation/protection of antioxidant defenses. Additionally, flavonoids can coordinate with transition metals to catalyze electron transport and promote free radical capture. Recently, metal ion chelation mechanisms have generated considerable interest, as experimental data show that flavonoids in metal complexes exhibit greater antioxidant activity than free flavonoids. However, few studies have correlated the complexing properties of flavonoids with their antioxidant capacity. Thus, the aim of this study was to use the CRAC (Ceric Reducing Antioxidant Capacity) electrochemical assay to measure the antioxidant capacity of five free flavonoids and Fe 2+ -flavonoid complexes. In addition, the interactions between the flavonoids and Fe 2+ were analyzed based on the oxidation peaks formed in their cyclic voltammograms

Sensory suppression of brain responses to self-generated sounds is observed with and without the perception of agency.

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Timm, Jana; Schönwiesner, Marc; Schröger, Erich; SanMiguel, Iria

2016-07-01

Stimuli caused by our own movements are given special treatment in the brain. Self-generated sounds evoke a smaller brain response than externally generated ones. This attenuated response may reflect a predictive mechanism to differentiate the sensory consequences of one's own actions from other sensory input. It may also relate to the feeling of being the agent of the movement and its effects, but little is known about how sensory suppression of brain responses to self-generated sounds is related to judgments of agency. To address this question, we recorded event-related potentials in response to sounds initiated by button presses. In one condition, participants perceived agency over the production of the sounds, whereas in another condition, participants experience an illusory lack of agency caused by changes in the delay between actions and effects. We compared trials in which the timing of button press and sound was physically identical, but participants' agency judgment differed. Results show reduced amplitudes of the auditory N1 component in response to self-generated sounds irrespective of agency experience, whilst P2 effects correlate with the perception of agency. Our findings suggest that suppression of the auditory N1 component to self-generated sounds does not depend on adaptation to specific action-effect time delays, and does not determine agency judgments, however, the suppression of the P2 component might relate more directly to the experience of agency. Copyright © 2016 Elsevier Ltd. All rights reserved.

Disruption of Ethylene Responses by Turnip mosaic virus Mediates Suppression of Plant Defense against the Green Peach Aphid Vector.

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Casteel, Clare L; De Alwis, Manori; Bak, Aurélie; Dong, Haili; Whitham, Steven A; Jander, Georg

2015-09-01

Plants employ diverse responses mediated by phytohormones to defend themselves against pathogens and herbivores. Adapted pathogens and herbivores often manipulate these responses to their benefit. Previously, we demonstrated that Turnip mosaic virus (TuMV) infection suppresses callose deposition, an important plant defense induced in response to feeding by its aphid vector, the green peach aphid (Myzus persicae), and increases aphid fecundity compared with uninfected control plants. Further, we determined that production of a single TuMV protein, Nuclear Inclusion a-Protease (NIa-Pro) domain, was responsible for changes in host plant physiology and increased green peach aphid reproduction. To characterize the underlying molecular mechanisms of this phenomenon, we examined the role of three phytohormone signaling pathways, jasmonic acid, salicylic acid, and ethylene (ET), in TuMV-infected Arabidopsis (Arabidopsis thaliana), with or without aphid herbivory. Experiments with Arabidopsis mutants ethylene insensitive2 and ethylene response1, and chemical inhibitors of ET synthesis and perception (aminoethoxyvinyl-glycine and 1-methylcyclopropene, respectively), show that the ET signaling pathway is required for TuMV-mediated suppression of Arabidopsis resistance to the green peach aphid. Additionally, transgenic expression of NIa-Pro in Arabidopsis alters ET responses and suppresses aphid-induced callose formation in an ET-dependent manner. Thus, disruption of ET responses in plants is an additional function of NIa-Pro, a highly conserved potyvirus protein. Virus-induced changes in ET responses may mediate vector-plant interactions more broadly and thus represent a conserved mechanism for increasing transmission by insect vectors across generations. © 2015 American Society of Plant Biologists. All Rights Reserved.

Antioxidative responses of Elodea nuttallii (Planch.) H. St. John to short-term iron exposure.

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Xing, Wei; Li, Dunhai; Liu, Guihua

2010-01-01

Antioxidative responses of Elodea nuttallii (Planch.) H. St. John to short-term iron exposure were investigated in the study. Results showed that iron accumulation in E. nuttallii was concentration dependent. Growth of E. nuttallii was promoted by low iron concentration (1-10 mg L(-1) [Fe(3+)]), but growth inhibition was observed when iron concentration beyond 10 mg L(-1). The synthesis of protein and pigments increased within 1-10 mg L(-1) [Fe(3+)] range. The activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and glutathione-S-transferase (GST) were up to maximal values at 10 mg L(-1) [Fe(3+)]. High iron concentration inhibited the synthesis of protein and pigments as well as activities of antioxidative enzymes, and accelerated degradation of pigment and production of ROS. Low iron concentration had no significant influences on PSII maximal quantum yield, activity of PSII and relative electron transport rate though PSII. Malondialdehyde (MDA) and proline concentrations were highest at 100 and 1 mg L(-1) [Fe(3+)], respectively. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Exogenous melatonin suppresses dark-induced leaf senescence by activating the superoxide dismutase-catalase antioxidant pathway and down-regulating chlorophyll degradation in excised leaves of perennial ryegrass (Lolium perenne L.

Directory of Open Access Journals (Sweden)

Jing Zhang

2016-10-01

Full Text Available Leaf senescence is a typical symptom in plants exposed to dark and may be regulated by plant growth regulators. The objective of this study was to determine whether exogenous application of melatonin (N-acetyl-5-methoxytryptamine suppresses dark-induced leaf senescence and the effects of melatonin on reactive oxygen species (ROS scavenging system and chlorophyll degradation pathway in perennial grass species. Mature perennial ryegrass (Lolium perenne L. cv. ‘Pinnacle’ leaves were excised and incubated in 3 mM 2-(N-morpholino ethanesulfonic buffer (pH 5.8 supplemented with melatonin or water (control and exposed to dark treatment for 8 d. Leaves treated with melatonin maintained significantly higher endogenous melatonin level, chlorophyll content, photochemical efficiency, and cell membrane stability expressed by lower electrolyte leakage and malondialdehyde (MDA content compared to the control. Exogenous melatonin treatment also reduced the transcript level of chlorophyll degradation-associated genes and senescence marker genes (LpSAG12.1, Lph36, and Lpl69 during the dark treatment. The endogenous O2- production rate and H2O2 content were significantly lower in these excised leaves treated with melatonin compared to the water control. Exogenous melatonin treatment caused increases in enzymatic activity and transcript levels of superoxide dismutase and catalase but had no significant effects on ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monohydroascorbate reductase. The content of non-enzymatic antioxidants, such as ascorbate and dehydroascorbate, were decreased by melatonin treatment, while the content of glutathione and oxidized glutathione was not affected by melatonin. These results suggest that the suppression of dark-induced leaf senescence by exogenous melatonin may be associated with its roles in regulating ROS scavenging through activating the superoxide dismutase-catalase enzymatic antioxidant

Substoichiometric hydroxynonenylation of a single protein recapitulates whole-cell-stimulated antioxidant response.

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Parvez, Saba; Fu, Yuan; Li, Jiayang; Long, Marcus J C; Lin, Hong-Yu; Lee, Dustin K; Hu, Gene S; Aye, Yimon

2015-01-14

Lipid-derived electrophiles (LDEs) that can directly modify proteins have emerged as important small-molecule cues in cellular decision-making. However, because these diffusible LDEs can modify many targets [e.g., >700 cysteines are modified by the well-known LDE 4-hydroxynonenal (HNE)], establishing the functional consequences of LDE modification on individual targets remains devilishly difficult. Whether LDE modifications on a single protein are biologically sufficient to activate discrete redox signaling response downstream also remains untested. Herein, using T-REX (targetable reactive electrophiles and oxidants), an approach aimed at selectively flipping a single redox switch in cells at a precise time, we show that a modest level (∼34%) of HNEylation on a single target is sufficient to elicit the pharmaceutically important antioxidant response element (ARE) activation, and the resultant strength of ARE induction recapitulates that observed from whole-cell electrophilic perturbation. These data provide the first evidence that single-target LDE modifications are important individual events in mammalian physiology.

Antioxidant responses and photosynthetic behaviors of Kappaphycus alvarezii and Kappaphycus striatum (Rhodophyta, Solieriaceae) during low temperature stress.

Science.gov (United States)

Li, Hu; Liu, Jianguo; Zhang, Litao; Pang, Tong

2016-12-01

Kappaphycus are farmed in tropical countries as raw material for carrageenan, which is widely used in food industry. The sea area available for farming is one limiting factor in the production of seaweeds. Though cultivation is spreading into subtropical regions, the lower seawater temperature is an important problem encountered in subtropical regions for the farming of Kappaphycus. This research of physiological response to low temperature stress will be helpful for screening Kappaphycus strains for growth in a lower temperature environment. Responses of antioxidant systems and photosystem II (PSII) behaviors in Kappaphycus alvarezii and Kappaphycus striatum were evaluated during low temperature treatments (23, 20, 17 °C). Compared with the controls at 26 °C, the H 2 O 2 concentrations increased in both species when the thalli were exposed to low temperatures (23, 20, 17 °C), but these increases were much greater in K. striatum than in K. alvarezii thalli, suggesting that K. striatum suffered more oxidative stress. The activities of some important antioxidant enzymes (e.g. superoxide dismutase and ascorbate peroxidase) and the hydroxyl free radical scavenging capacity were substantially higher at 23, 20 and 17 °C than at the control 26 °C in K. alvarezii, indicating that the antioxidant system of K. alvarezii enhanced its resistance to low temperature. However, no significant increases of antioxidant enzymes activities were observed at 20 and 17 °C in K. striatum. In addition, both the maximal efficiency of PSII photochemistry (F V /F m ) and the performance index (PI ABS ) decreased significantly in K. striatum at 23 °C, indicating that the photosynthetic apparatus was damaged at 23 °C. In contrast, no significant decreases of either F V /F m or PI ABS were observed in K. alvarezii at 23 °C. It is concluded that K. alvarezii has greater tolerance to low temperature than K. striatum.

The effects of dietary soybean isoflavones on growth, innate immune responses, hepatic antioxidant abilities and disease resistance of juvenile golden pompano Trachinotus ovatus.

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Zhou, Chuanpeng; Lin, Heizhao; Ge, Xianping; Niu, Jin; Wang, Jun; Wang, Yun; Chen, Lixiong; Huang, Zhong; Yu, Wei; Tan, Xiaohong

2015-03-01

The present study was conducted to investigate the effects of dietary soybean isoflavones (SI) supplementation on growth performance, innate immune responses, hepatic antioxidant abilities, heat shock protein 70 (HSP70) gene expression and resistance to the pathogen Vibrio harveyi in Trachinotus ovatus. A basal diet was supplemented with SI at 0, 10, 20, 40, 60, 80 mg kg(-1) feed for 8 weeks. Significantly maximum weight gain (WG) and specific growth rate (SGR) were observed in treatment with 40 mg kg(-1) SI supplement (P growth, non-specific immune responses, hepatic antioxidant abilities and HSP70 gene expression. Copyright © 2015 Elsevier Ltd. All rights reserved.

Helminth-induced regulatory T cells and suppression of allergic responses.

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Logan, Jayden; Navarro, Severine; Loukas, Alex; Giacomin, Paul

2018-05-28

Infection with helminths has been associated with lower rates of asthma and other allergic diseases. This has been attributed, in part, to the ability of helminths to induce regulatory T cells that suppress inappropriate immune responses to allergens. Recent compelling evidence suggests that helminths may promote regulatory T cell expansion or effector functions through either direct (secretion of excretory/secretory molecules) or indirect mechanisms (regulation of the microbiome). This review will discuss key findings from human immunoepidemiological observations, studies using animal models of disease, and clinical trials with live worm infections, discussing the therapeutic potential for worms and their secreted products for treating allergic inflammation. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

Accumulation and detoxification dynamics of Chromium and antioxidant responses in juvenile rare minnow, Gobiocypris rarus.

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Yuan, Cong; Li, Meng; Zheng, Yao; Zhou, Ying; Wu, Feili; Wang, Zaizhao

2017-09-01

Hexavalent chromium (Cr 6+ ) compounds are hazardous via all exposure routes. To explore the dynamics of Cr accumulation and elimination and to reveal the mechanisms underlying detoxification and antioxidation in juvenile Gobiocypris rarus, one-month old G. rarus larvae were exposed to 0.1mgL -1 Cr 6+ for four weeks for accumulation and subsequently placed to clean water for another week for depuration. The contents of Cr were measured weekly in the whole body of G. rarus juveniles. The activities of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), glutathione S-transferase (GST) and glutathione reductase (GR), and contents of glutathione (GSH) and malonaldehyde (MDA), and transcripts of cat, Cu/Zn-sod, Mn-sod, gpx1, gstpi, gr, mt1, nrf2 and uba52 were determined. The results indicated that G. rarus juveniles had a strong ability to resist the Cr accumulation by Cr 6+ exposure and to remove Cr from the body in clean water. In addition, GST and MT proteins may be involved in the detoxification of Cr 6+ . Moreover, Cr 6+ -induced GST detoxification in G. rarus juveniles might be accomplished through the Nrf2-mediated regulation of gene expressions. The antioxidant enzyme systems exhibited a response mechanism of the protective enzymes in organisms when they are subjected to external environmental stress. Two weeks of Cr 6+ treatments could have led to the damage and consecutive degradation of antioxidant enzymes via ubiquitination, and MT proteins could be involved in protecting the activity of these enzymes. The capability of antioxidant enzyme systems to recover from the Cr 6+ -induced damage was strong in G. rarus juveniles after Cr 6+ was removed from the water. Copyright © 2017 Elsevier B.V. All rights reserved.

Antioxidant and Anti-Osteoporosis Activities of Chemical Constituents of the Stems of Zanthoxylum piperitum

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Seo Young Yang

2018-02-01

Full Text Available Two new lignans, zanthoxyloside C (1 and zanthoxyloside D (2, together with nine known compounds comprising lignans (3–5, flavonoids (6–8, and phenolics (9–11, were isolated from the methanol extract of the stems of Zanthoxylum piperitum. All isolates were evaluated for their antioxidant and anti-osteoporotic activities using oxygen radical absorbance capacity (ORAC, cupric reducing antioxidant capacity (CUPRAC, and tartrate-resistant acid phosphatase (TRAP assays. Compounds 7–10 showed peroxyl radical-scavenging capacities and 4, 6–7, and 9 showed reducing capacities. Moreover, compounds 3, 6–9, and 11 significantly suppressed TRAP activities. These results indicated that the stems of Z. piperitum could be an excellent source for natural antioxidant and anti-osteoporosis.

Treatment of silymarin, a plant flavonoid, prevents ultraviolet light-induced immune suppression and oxidative stress in mouse skin.

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Katiyar, Santosh K

2002-12-01

It is well documented that ultraviolet (UV) light-induced immune suppression and oxidative stress play an important role in the induction of skin cancers. Earlier, we have shown that topical treatment of silymarin, a plant flavonoid from milk thistle (Silybum marianum L. Gaertn.), to mouse skin prevents photocarcinogenesis, but the preventive mechanism of photocarcinogenesis in vivo animal system by silymarin is not well defined and understood. To define the mechanism of prevention, we employed immunostaining, analytical assays and ELISA which revealed that topical treatment of silymarin (1 mg/cm2 skin area) to C3H/HeN mice inhibits UVB (90 mJ/cm2)-induced suppression of contact hypersensitivity (CHS) response to contact sensitizer dinitrofluorobenzene. Prevention of UVB-induced suppression of CHS by silymarin was found to be associated with the inhibition of infiltrating leukocytes, particularly CD11b+ cell type, and myeloperoxidase activity (50-71%). Silymarin treatment also resulted in significant reduction of UVB-induced immunosuppressive cytokine interleukin-10 producing cells and its production (58-72%, pskin cancer risk human population and ii) development of sunscreen containing silymarin as an antioxidant (chemopreventive agent) or silymarin can be supplemented in skin care products.

Accumulation of free polyamines enhances the antioxidant response in fruits of grafted tomato plants under water stress.

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Sánchez-Rodríguez, E; Romero, L; Ruiz, J M

2016-01-15

Polyamines, small aliphatic polycations, have been suggested to play key roles in a number of biological processes. In this paper, attempts were made to investigate the possibility of improving antioxidant response of tomato fruits in relation with endogenous free polyamines content. We studied the reactive oxygen species and polyamines content, and antioxidant and polyamine-biosynthesis enzyme activities in fruits of ungrafted and grafted tomato plants under moderate water stress. We used a drought-tolerant cultivar (Zarina) and drought-sensitive cultivar (Josefina) to obtain reciprocal graft, selfgraft and ungraft plants. Fruits contained higher endogenous polyamine content during the course of the experiment relative to the control, coupled with higher arginine decarboxylase and spermine synthase activities in Zarina ungrafted and ZarxJos. In these cultivars, tomato fruits showed a lower reactive oxygen species generation and higher catalase and superoxide dismutase activities, suggesting that a higher content in polyamines (especially spermine) exerted a positive effect on antioxidant systems. All of these data suggest that spermine leads to more effective reactive oxygen species scavenging (less tissue damage) in tomato fruits, which may function collectively to enhance dehydration tolerance. Copyright © 2015 Elsevier GmbH. All rights reserved.

Crimean-Congo Hemorrhagic Fever Virus Suppresses Innate Immune Responses via a Ubiquitin and ISG15 Specific Protease

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Florine E.M. Scholte

2017-09-01

Full Text Available Antiviral responses are regulated by conjugation of ubiquitin (Ub and interferon-stimulated gene 15 (ISG15 to proteins. Certain classes of viruses encode Ub- or ISG15-specific proteases belonging to the ovarian tumor (OTU superfamily. Their activity is thought to suppress cellular immune responses, but studies demonstrating the function of viral OTU proteases during infection are lacking. Crimean-Congo hemorrhagic fever virus (CCHFV, family Nairoviridae is a highly pathogenic human virus that encodes an OTU with both deubiquitinase and deISGylase activity as part of the viral RNA polymerase. We investigated CCHFV OTU function by inactivating protease catalytic activity or by selectively disrupting its deubiquitinase and deISGylase activity using reverse genetics. CCHFV OTU inactivation blocked viral replication independently of its RNA polymerase activity, while deubiquitinase activity proved critical for suppressing the interferon responses. Our findings provide insights into viral OTU functions and support the development of therapeutics and vaccines.

Simultaneous optimization of the ultrasound-assisted extraction for phenolic compounds content and antioxidant activity of Lycium ruthenicum Murr. fruit using response surface methodology.

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Chen, Shasha; Zeng, Zhi; Hu, Na; Bai, Bo; Wang, Honglun; Suo, Yourui

2018-03-01

Lycium ruthenicum Murr. (LR) is a functional food that plays an important role in anti-oxidation due to its high level of phenolic compounds. This study aims to optimize ultrasound-assisted extraction (UAE) of phenolic compounds and antioxidant activities of obtained extracts from LR using response surface methodology (RSM). A four-factor-three-level Box-Behnken design (BBD) was employed to discuss the following extracting parameters: extraction time (X 1 ), ultrasonic power (X 2 ), solvent to sample ratio (X 3 ) and solvent concentration (X 4 ). The analysis of variance (ANOVA) results revealed that the solvent to sample ratio had a significant influence on all responses, while the extraction time had no statistically significant effect on phenolic compounds. The optimum values of the combination of phenolic compounds and antioxidant activities were obtained for X 1 =30min, X 2 =100W, X 3 =40mL/g, and X 4 =33% (v/v). Five phenolic acids, including chlorogenic acid, caffeic acid, syringic acid, p-coumaric acid and ferulic acid, were analyzed by HPLC. Our results indicated that optimization extraction is vital for the quantification of phenolic compounds and antioxidant activity in LR, which may be contributed to large-scale industrial applications and future pharmacological activities research. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biomarkers of oxidative stress and of antioxidative defense: Relationship to intervention with antioxidant-rich foods

DEFF Research Database (Denmark)

Dragsted, Lars Ove; Young, Jette Feveile; Loft, Steffen

2001-01-01

polyphenol intake was observed. There was an increased oxidative stress response toward plasma proteins from food items rich in polyphenols and vitamin C and a decreased response when fruits and vegetables were omitted using a controlled diet. There also was a similar trend toward increased antioxidant...

Antioxidants and the Comet assay.

Science.gov (United States)

Cemeli, Eduardo; Baumgartner, Adolf; Anderson, Diana

2009-01-01

It is widely accepted that antioxidants, either endogenous or from the diet, play a key role in preserving health. They are able to quench radical species generated in situations of oxidative stress, either triggered by pathologies or xenobiotics, and they protect the integrity of DNA from genotoxicants. Nevertheless, there are still many compounds with unclear or unidentified prooxidant/antioxidant activities. This is of concern since there is an increase in the number of compounds synthesized or extracted from vegetables to which humans might be exposed. Despite the well-established protective effects of fruit and vegetables, the antioxidant(s) responsible have not all been clearly identified. There might also be alternative mechanisms contributing to the protective effects for which a comprehensive description is lacking. In the last two decades, the Comet assay has been extensively used for the investigation of the effects of antioxidants and many reports can be found in the literature. The Comet assay, a relatively fast, simple, and sensitive technique for the analysis of DNA damage in all cell types, has been applied for the screening of chemicals, biomonitoring and intervention studies. In the present review, several of the most well-known antioxidants are considered. These include: catalase, superoxide dismutase, glutathione peroxidase, selenium, iron chelators, melatonin, melanin, vitamins (A, B, C and E), carotenes, flavonoids, isoflavones, tea polyphenols, wine polyphenols and synthetic antioxidants. Investigations showing beneficial as well as non-beneficial properties of the antioxidants selected, either at the in vitro, ex vivo or in vivo level are discussed.

Phenolic content and antioxidant activities of burr parsley (Caucalis platycarpos L.).

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Plazonić, Ana; Mornar, Ana; Maleš, Željan; Kujundžić, Nikola

2013-07-22

Since C. platycarpos contains a wide variety of antioxidants, in the present study total flavonoid and phenolic acid content as well as antioxidative activity of various C. platycarpos extracts were investigated. The results obtained show a significant polyphenol content and antioxidant activity of the investigated plant. Moreover, a positive correlation between antioxidant activity and content of flavonoids and phenolic acids was found, indicating the responsibility of these compounds for the antioxidant effectiveness of C. platycarpos extracts and making C. platycarpos a good potential source of natural antioxidants.

Antioxidant Protection in Blood against Ionising Radiation

International Nuclear Information System (INIS)

Bognar, G.; Meszaros, G.; Koteles, G. J.

2001-01-01

Full text: The quantities of the antioxidants in the human blood are important indicators of health status. The routine determinations of activities/capacities of antioxidant compounds would be of great importance in assessing individual sensitivities against oxidative effects. We have investigated the sensitivities of those antioxidant elements against various doses of ionising radiation tested by the RANDOX assays. Our results show dose-dependent decreases of antioxidant activities caused by the different doses. The total antioxidant status value linearly decreased up to 1 Gy, but further increase of dose (2 Gy) did not influence the respective values although the test system still indicated their presence. It means that the human blood retains 60-70% of its total antioxidant capacity. Radiation induced alterations of the antioxidant enzymes: glutathione peroxidase and superoxide dismutase have been also investigated. The activities of glutathione peroxidase and superoxide dismutase decreased linearly upon the effects of various doses of ionising radiation till 1 Gy. Between 1 and 2 Gy only further mild decreases could be detected. In this case the human blood retained 40-60% of these two antioxidant enzymes. These observations suggest either the limited response of antioxidant system against ionising radiation, or the existence of protection system of various reactabilities. (author)

MicroRNA203a suppresses glioma tumorigenesis through an ATM-dependent interferon response pathway.

Science.gov (United States)

Yang, Chuan He; Wang, Yinan; Sims, Michelle; Cai, Chun; He, Ping; Häcker, Hans; Yue, Junming; Cheng, Jinjun; Boop, Frederick A; Pfeffer, Lawrence M

2017-12-22

Glioblastoma (GBM) is a deadly and incurable brain tumor. Although microRNAs (miRNAs) play critical roles in regulating the cancer cell phenotype, the underlying mechanisms of how they regulate tumorigenesis are incompletely understood. We previously showed that miR-203a is expressed at relatively low levels in GBM patients, and ectopic miR-203a expression in GBM cell lines inhibited cell proliferation and migration, increased sensitivity to apoptosis induced by interferon (IFN) or temozolomide in vitro , and inhibited GBM tumorigenesis in vivo . Here we show that ectopic expression of miR-203a in GBM cell lines promotes the IFN response pathway as evidenced by increased IFN production and IFN-stimulated gene (ISG) expression, and high basal tyrosine phosphorylation of multiple STAT proteins. Importantly, we identified that miR-203a directly suppressed the protein levels of ataxia-telangiectasia mutated (ATM) kinase that negatively regulates IFN production. We found that high ATM expression in GBM correlates with poor patient survival and that ATM expression is inversely correlated with miR-203a expression. Knockout of ATM expression and inhibition of ATM function in GBM cell lines inhibited cell proliferation and migration, increased sensitivity to apoptosis induced by therapeutic agents in vitro , and markedly suppressed GBM tumor growth and promoted animal survival. In contrast, restoring ATM levels in GBM cells ectopically expressing miR-203a increased tumorigenicity and decreased animal survival. Our study suggests that low miR-203a expression in GBM suppresses the interferon response through an ATM-dependent pathway.

Non-tip auditory-nerve responses that are suppressed by low-frequency bias tones originate from reticular lamina motion.

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Nam, Hui; Guinan, John J

2017-12-14

Recent cochlear mechanical measurements show that active processes increase the motion response of the reticular lamina (RL) at frequencies more than an octave below the local characteristic frequency (CF) for CFs above 5 kHz. A possible correlate is that in high-CF (>5 kHz) auditory-nerve (AN) fibers, responses to frequencies 1-3 octaves below CF ("tail" frequencies) can be inhibited by medial olivocochlear (MOC) efferents. These results indicate that active processes enhance the sensitivity of tail-frequency RL and AN responses. Perhaps related is that some apical low-CF AN fibers have tuning-curve (TC) "side-lobe" response areas at frequencies above and below the TC-tip that are MOC inhibited. We hypothesized that the tail and side-lobe responses are enhanced by the same active mechanisms as CF cochlear amplification. If responses to CF, tail-frequency, and TC-side-lobe tones are all enhanced by prestin motility controlled by outer-hair-cell (OHC) transmembrane voltage, then they should depend on OHC stereocilia position in the same way. To test this, we cyclically changed the OHC-stereocilia mechano-electric-transduction (MET) operating point with low-frequency "bias" tones (BTs) and increased the BT level until the BT caused quasi-static OHC MET saturation that reduced or "suppressed" the gain of OHC active processes. While measuring cat AN-fiber responses, 50 Hz BT level series, 70-120 dB SPL, were run alone and with CF tones, or 2.5 kHz tail-frequency tones, or side-lobe tones. BT-tone-alone responses were used to exclude BT sound levels that produced AN responses that might obscure BT suppression. Data were analyzed to show the BT phase that suppressed the tone responses at the lowest sound level. We found that AN responses to CF, tail-frequency, and side-lobe tones were suppressed at the same BT phase in almost all cases. The data are consistent with the enhancement of responses to CF, tail-frequency, and side-lobe tones all being due to the same

Phenotypes, antioxidant responses, and gene expression changes accompanying a sugar-only diet in Bactrocera dorsalis (Hendel) (Diptera: Tephritidae).

Science.gov (United States)

Chen, Er-Hu; Hou, Qiu-Li; Wei, Dan-Dan; Jiang, Hong-Bo; Wang, Jin-Jun

2017-08-17

Diet composition (yeast:carbohydrate ratio) is an important determinant of growth, development, and reproduction. Recent studies have shown that decreased yeast intake elicits numerous transcriptomic changes and enhances somatic maintenance and lifespan, which in turn reduces reproduction in various insects. However, our understanding of the responses leading to a decrease in yeast ratio to 0% is limited. In the present study, we investigated the effects of a sugar-only diet (SD) on the gene expression patterns of the oriental fruit fly, Bactrocera dorsalis (Hendel), one of the most economically important pests in the family Tephritidae. RNA sequencing analyses showed that flies reared on an SD induced significant changes in the expression levels of genes associated with specific metabolic as well as cell growth and death pathways. Moreover, the observed upregulated genes in energy production and downregulated genes associated with reproduction suggested that SD affects somatic maintenance and reproduction in B. dorsalis. As expected, we observed that SD altered B. dorsalis phenotypes by significantly increasing stress (starvation and desiccation) resistance, decreasing reproduction, but did not extend lifespan compared to those that received a normal diet (ND) regime. In addition, administration of an SD resulted in a reduction in antioxidant enzyme activities and an increase in MDA concentrations, thereby suggesting that antioxidants cannot keep up with the increase in oxidative damage induced by SD regime. The application of an SD diet induces changes in phenotypes, antioxidant responses, and gene expressions in B. dorsalis. Previous studies have associated extended lifespan with reduced fecundity. The current study did not observe a prolongation of lifespan in B. dorsalis, which instead incurred oxidative damage. The findings of the present study improve our understanding of the molecular, biochemical, and phenotypic response of B. dorsalis to an SD diet.

Anti-cancer and antioxidant properties of phenolics isolated from ...

African Journals Online (AJOL)

Results: The extract contained 36.02 ± 0.24 mg of gallic acid equiv/g dry ... Keywords: Toona sinensis, Phenolics, Antioxidants, HepG2 cells, Anti- ... EXPERIMENTAL .... Figure 2: Time kinetics and dose-response of hydrophilic antioxidant ...

Optimization of microwave-assisted extraction for anthocyanins, polyphenols, and antioxidants from raspberry (Rubus Coreanus Miq.) using response surface methodology.

Science.gov (United States)

Teng, Hui; Lee, Won Young; Choi, Yong Hee

2013-09-01

Anthocyanins (Acys), polyphenols, and antioxidants were extracted from raspberry (Rubus Coreanus Miq.) using a highly efficient microwave-assisted extraction technique. Different solvents, including methanol, ethanol, and acetone, were tested. The colors of the extracts varied from light yellow to purple red or dark red. SEM and other nutrient analyses verified that ethanol was the most favorable medium for the microwave-assisted extraction of raspberry due to its high output and low toxicity. Effects of process parameters, including microwave power, irradiation time, and solvent concentration, were investigated through response surface methodology. Canonical analysis estimated that the highest total Acys content, total polyphenols content, and antioxidant activity of raspberry were 17.93 mg cyanidin-3-O-glucoside equivalents per gram dry weight, 38.57 mg gallic acid equivalents per gram dry weight, and 81.24%, respectively. The polyphenol compositions of raspberry extract were identified by HPLC with diode array detection, and nine kinds of polyphenols were identified and quantified, revealing that chlorogenic acid, syringic acid, and rutin are the major polyphenols contained in raspberry fruits. Compared with other fruits and vegetables, raspberry contains higher Acy and polyphenol contents with stronger antioxidant activity, suggesting that raspberry fruits are a good source of natural food colorants and antioxidants. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phenolic Content and Antioxidant Activities of Burr Parsley (Caucalis platycarpos L.

Directory of Open Access Journals (Sweden)

Željan Maleš

2013-07-01

Full Text Available Since C. platycarpos contains a wide variety of antioxidants, in the present study total flavonoid and phenolic acid content as well as antioxidative activity of various C. platycarpos extracts were investigated. The results obtained show a significant polyphenol content and antioxidant activity of the investigated plant. Moreover, a positive correlation between antioxidant activity and content of flavonoids and phenolic acids was found, indicating the responsibility of these compounds for the antioxidant effectiveness of C. platycarpos extracts and making C. platycarpos a good potential source of natural antioxidants.

Antiradical and antioxidant activities of new bio-antioxidants.

Science.gov (United States)

Kancheva, V D; Saso, L; Angelova, S E; Foti, M C; Slavova-Kasakova, A; Daquino, C; Enchev, V; Firuzi, O; Nechev, J

2012-02-01

Antioxidants could be promising agents for management of oxidative stress-related diseases. New biologically active compounds, belonging to a rare class of natural lignans with antiangiogenic, antitumoral and DNA intercalating properties, have been recently synthesized. These compounds are benzo[kl]xanthene lignans (1,2) and dihydrobenzofuran neolignans (3,4). The radical scavenging and chain-breaking antioxidant activities of compounds 1-4 were studied by applying different methods: radical scavenging activity by DPPH rapid test, chain-breaking antioxidant activity and quantum chemical calculations. All studied compounds were found to be active as DPPH scavengers but reaction time with DPPH and compounds' concentrations influenced deeply the evaluation. The highest values of radical scavenging activity (%RSAmax) and largest rate constants for reaction with DPPH were obtained for compounds 2 and 3. Comparison of %RSAmax with that of standard antioxidants DL-α-tocopherol (TOH), caffeic acid (CA) and butylated hydroxyl toluene (BHT) give the following new order of %RSA max: TOH (61.1%) > CA (58.6%) > 3 (36.3%) > 2 (28.1%) > 4 (6.7%) > 1 (3.6%) = BHT (3.6%). Chain-breaking antioxidant activities of individual compounds (0.1-1.0 mM) and of their equimolar binary mixtures (0.1 mM) with TOH were determined from the kinetic curves of lipid autoxidation at 80 °C. On the basis of a comparable kinetic analysis with standard antioxidants a new order of the antioxidant efficiency (i.e., protection factor, PF) of compounds 1-4 were obtained: 2 (7.2) ≥ TOH (7.0) ≥ CA (6.7) > 1 (3.1) > 3 (2.2) > ferulic acid FA (1.5) > 4 (0.6); and of the antioxidant reactivity (i.e. inhibition degree, ID): 2 (44.0) > TOH (18.7) > CA (9.3) > 1 (8.4) > 3 (2.8) > FA (1.0) > 4 (0.9). The important role of the catecholic structure in these compounds, which is responsible for the high chain-breaking antioxidant activity, is discussed and a reaction

Human Leukemic Cells performing Oxidative Phosphorylation (OXPHOS Generate an Antioxidant Response Independently of Reactive Oxygen species (ROS Production

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Abrar Ul Haq Khan

2016-01-01

Full Text Available Tumor cell metabolism is altered during leukemogenesis. Cells performing oxidative phosphorylation (OXPHOS generate reactive oxygen species (ROS through mitochondrial activity. To limit the deleterious effects of excess ROS, certain gene promoters contain antioxidant response elements (ARE, e.g. the genes NQO-1 and HO-1. ROS induces conformational changes in KEAP1 and releases NRF2, which activates AREs. We show in vitro and in vivo that OXPHOS induces, both in primary leukemic cells and cell lines, de novo expression of NQO-1 and HO-1 and also the MAPK ERK5 and decreases KEAP1 mRNA. ERK5 activates the transcription factor MEF2, which binds to the promoter of the miR-23a–27a–24-2 cluster. Newly generated miR-23a destabilizes KEAP1 mRNA by binding to its 3′UTR. Lower KEAP1 levels increase the basal expression of the NRF2-dependent genes NQO-1 and HO-1. Hence, leukemic cells performing OXPHOS, independently of de novo ROS production, generate an antioxidant response to protect themselves from ROS.

Changes in antioxidants are critical in determining cell responses to short- and long-term heat stress.

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Sgobba, Alessandra; Paradiso, Annalisa; Dipierro, Silvio; De Gara, Laura; de Pinto, Maria Concetta

2015-01-01

Heat stress can have deleterious effects on plant growth by impairing several physiological processes. Plants have several defense mechanisms that enable them to cope with high temperatures. The synthesis and accumulation of heat shock proteins (HSPs), as well as the maintenance of an opportune redox balance play key roles in conferring thermotolerance to plants. In this study changes in redox parameters, the activity and/or expression of reactive oxygen species (ROS) scavenging enzymes and the expression of two HSPs were studied in tobacco Bright Yellow-2 (TBY-2) cells subjected to moderate short-term heat stress (SHS) and long-term heat stress (LHS). The results indicate that TBY-2 cells subjected to SHS suddenly and transiently enhance antioxidant systems, thus maintaining redox homeostasis and avoiding oxidative damage. The simultaneous increase in HSPs overcomes the SHS and maintains the metabolic functionality of cells. In contrast the exposure of cells to LHS significantly reduces cell growth and increases cell death. In the first phase of LHS, cells enhance antioxidant systems to prevent the formation of an oxidizing environment. Under prolonged heat stress, the antioxidant systems, and particularly the enzymatic ones, are inactivated. As a consequence, an increase in H2 O2 , lipid peroxidation and protein oxidation occurs. This establishment of oxidative stress could be responsible for the increased cell death. The rescue of cell growth and cell viability, observed when TBY-2 cells were pretreated with galactone-γ-lactone, the last precursor of ascorbate, and glutathione before exposure to LHS, highlights the crucial role of antioxidants in the acquisition of basal thermotolerance. © 2014 Scandinavian Plant Physiology Society.

Deconstructing Interocular Suppression: Attention and Divisive Normalization.

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Hsin-Hung Li

2015-10-01

Full Text Available In interocular suppression, a suprathreshold monocular target can be rendered invisible by a salient competitor stimulus presented in the other eye. Despite decades of research on interocular suppression and related phenomena (e.g., binocular rivalry, flash suppression, continuous flash suppression, the neural processing underlying interocular suppression is still unknown. We developed and tested a computational model of interocular suppression. The model included two processes that contributed to the strength of interocular suppression: divisive normalization and attentional modulation. According to the model, the salient competitor induced a stimulus-driven attentional modulation selective for the location and orientation of the competitor, thereby increasing the gain of neural responses to the competitor and reducing the gain of neural responses to the target. Additional suppression was induced by divisive normalization in the model, similar to other forms of visual masking. To test the model, we conducted psychophysics experiments in which both the size and the eye-of-origin of the competitor were manipulated. For small and medium competitors, behavioral performance was consonant with a change in the response gain of neurons that responded to the target. But large competitors induced a contrast-gain change, even when the competitor was split between the two eyes. The model correctly predicted these results and outperformed an alternative model in which the attentional modulation was eye specific. We conclude that both stimulus-driven attention (selective for location and feature and divisive normalization contribute to interocular suppression.

Deconstructing Interocular Suppression: Attention and Divisive Normalization.

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Li, Hsin-Hung; Carrasco, Marisa; Heeger, David J

2015-10-01

In interocular suppression, a suprathreshold monocular target can be rendered invisible by a salient competitor stimulus presented in the other eye. Despite decades of research on interocular suppression and related phenomena (e.g., binocular rivalry, flash suppression, continuous flash suppression), the neural processing underlying interocular suppression is still unknown. We developed and tested a computational model of interocular suppression. The model included two processes that contributed to the strength of interocular suppression: divisive normalization and attentional modulation. According to the model, the salient competitor induced a stimulus-driven attentional modulation selective for the location and orientation of the competitor, thereby increasing the gain of neural responses to the competitor and reducing the gain of neural responses to the target. Additional suppression was induced by divisive normalization in the model, similar to other forms of visual masking. To test the model, we conducted psychophysics experiments in which both the size and the eye-of-origin of the competitor were manipulated. For small and medium competitors, behavioral performance was consonant with a change in the response gain of neurons that responded to the target. But large competitors induced a contrast-gain change, even when the competitor was split between the two eyes. The model correctly predicted these results and outperformed an alternative model in which the attentional modulation was eye specific. We conclude that both stimulus-driven attention (selective for location and feature) and divisive normalization contribute to interocular suppression.

Continuous activation of Nrf2 and its target antioxidant enzymes leads to arsenite-induced malignant transformation of human bronchial epithelial cells

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Yang, Xu [Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, Jiangsu (China); Wang, Dapeng [Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, Jiangsu (China); Department of Toxicology, School of Public Health, Guizhou Medical University, Guiyang, Guizhou (China); Ma, Yuan; Xu, Xiguo; Zhu, Zhen; Wang, Xiaojuan; Deng, Hanyi; Li, Chunchun; Chen, Min; Tong, Jian [Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, Jiangsu (China); Yamanaka, Kenzo [Laboratory of Environmental Toxicology and Carcinogenesis, School of Pharmacy, Nihon University, Chiba (Japan); An, Yan, E-mail: dranyan@126.com [Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, Jiangsu (China)

2015-12-01

Long-term exposure to arsenite leads to human lung cancer, but the underlying mechanisms of carcinogenesis remain obscure. The transcription factor of nuclear factor-erythroid-2 p45-related factor (Nrf2)-mediated antioxidant response represents a critical cellular defense mechanism and protection against various diseases. Paradoxically, emerging data suggest that the constitutive activation of Nrf2 is associated with cancer development, progression and chemotherapy resistance. However, the role of Nrf2 in the occurrence of cancer induced by long-term arsenite exposure remains to be fully understood. By establishing transformed human bronchial epithelial (HBE) cells via chronic low-dose arsenite treatment, we showed that, in acquiring this malignant phenotype, continuous low level of ROS and sustained enhancement of Nrf2 and its target antioxidant enzyme levels were observed in the later-stage of arsenite-induced cell transformation. The downregulation of Keap1 level may be responsible for the over-activation of Nrf2 and its target enzymes. To validate these observations, Nrf2 was knocked down in arsenite-transformed HBE cells by SiRNA transfection, and the levels of Nrf2 and its target antioxidant enzymes, ROS, cell proliferation, migration, and colony formation were determined following these treatments. Results showed that blocked Nrf2 expression significantly reduced Nrf2 and its target antioxidant enzyme levels, restored ROS levels, and eventually suppressed cell proliferation, migration, and colony formation of the transformed cells. In summary, the results of the study strongly suggested that the continuous activation of Nrf2 and its target antioxidant enzymes led to the over-depletion of intracellular ROS levels, which contributed to arsenite-induced HBE cell transformation. - Highlights: • Low level, long term arsenite exposure induces malignant transformation in vitro. • Long term arsenite exposure reduces ROS and MDA levels. • Long term arsenite

Continuous activation of Nrf2 and its target antioxidant enzymes leads to arsenite-induced malignant transformation of human bronchial epithelial cells

International Nuclear Information System (INIS)

Yang, Xu; Wang, Dapeng; Ma, Yuan; Xu, Xiguo; Zhu, Zhen; Wang, Xiaojuan; Deng, Hanyi; Li, Chunchun; Chen, Min; Tong, Jian; Yamanaka, Kenzo; An, Yan

2015-01-01

Long-term exposure to arsenite leads to human lung cancer, but the underlying mechanisms of carcinogenesis remain obscure. The transcription factor of nuclear factor-erythroid-2 p45-related factor (Nrf2)-mediated antioxidant response represents a critical cellular defense mechanism and protection against various diseases. Paradoxically, emerging data suggest that the constitutive activation of Nrf2 is associated with cancer development, progression and chemotherapy resistance. However, the role of Nrf2 in the occurrence of cancer induced by long-term arsenite exposure remains to be fully understood. By establishing transformed human bronchial epithelial (HBE) cells via chronic low-dose arsenite treatment, we showed that, in acquiring this malignant phenotype, continuous low level of ROS and sustained enhancement of Nrf2 and its target antioxidant enzyme levels were observed in the later-stage of arsenite-induced cell transformation. The downregulation of Keap1 level may be responsible for the over-activation of Nrf2 and its target enzymes. To validate these observations, Nrf2 was knocked down in arsenite-transformed HBE cells by SiRNA transfection, and the levels of Nrf2 and its target antioxidant enzymes, ROS, cell proliferation, migration, and colony formation were determined following these treatments. Results showed that blocked Nrf2 expression significantly reduced Nrf2 and its target antioxidant enzyme levels, restored ROS levels, and eventually suppressed cell proliferation, migration, and colony formation of the transformed cells. In summary, the results of the study strongly suggested that the continuous activation of Nrf2 and its target antioxidant enzymes led to the over-depletion of intracellular ROS levels, which contributed to arsenite-induced HBE cell transformation. - Highlights: • Low level, long term arsenite exposure induces malignant transformation in vitro. • Long term arsenite exposure reduces ROS and MDA levels. • Long term arsenite

Antioxidative response of Lepidium sativum L. during assisted phytoremediation of Hg contaminated soil.

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Smolinska, Beata; Szczodrowska, Agnieszka

2017-09-25

In this study, Lepidium sativum L. was used in repeated phytoextraction processes to remove Hg from contaminated soil, assisted by combined use of compost and iodide (KI). L. sativum L. is sensitive to changes in environmental conditions and has been used in environmental tests. Its short vegetation period and ability to accumulate heavy metals make it suitable for use in repeated phytoextraction. The antioxidant enzymatic system of the plant (catalase (CAT), ascorbate peroxidase (APX), superoxide dismutase (SOD) and glutathione S-transferase (GST)) was analysed, to understand the effects of increasing Hg accumulation and translocation. Phytoextraction was repeated six times to decrease Hg contamination in soil, and the efficiency of each step was assessed. The results indicate that L. sativum L. is able to take up and accumulate Hg from contaminated soil. A corresponding increase in enzymatic antioxidants shows that the plant defence system is activated in response to Hg stress. Using compost and KI increases total Hg accumulation and translocation to the above-ground parts of L. sativum L. Repeating the process decreases Hg contamination in pot experiments in all variants of the process. The combined use of compost and KI during repeated phytoextraction increases the efficiency of Hg removal from contaminated soil. Copyright © 2016 Elsevier B.V. All rights reserved.

Permanence of suppression of the primary immune response in rainbow trout, Salmo gairdneri, sublethally exposed to tritiated water during embryognesis

International Nuclear Information System (INIS)

Strand, J.A.; Fujihara, M.P.; Poston, T.M.; Abernethy, C.S.

1982-01-01

Previous experiments demonstrated that antibody synthesis in response to a challenge from the bacterium, Flexibacter columnaris, was significantly suppressed in juvenile (5 month) rainbow trout following exposure to tritium at doses as low as 4.0 rads when administered during the first 20 days of embryogenesis. In continuing studies, a secondary challenge to columnaris cells delivered to yearling (17 month) trout was used to test the hypothesis that early embryonic exposure to tritium irradiation (0, 0.04, 0.4, 4.0, and 40.0 rads) resulted in permanent injury to the primary immune process. Results indicated that under the prescribed experimental conditions, suppression of the primary immune response was permanent; that is, the degree of injury in yearling fish (17 months) equaled or exceeded that found in juvenile fish (5 months). At levels in the range of the maximum permissible concentration (MPC), tritium produced measurable, dose dependent, and irreversible suppression of immune capacity in affected fish. The threshold-free and exponential nature of the dose-response curve suggests extrapolation of effects to even lower exposures. (author)

Evaluation of the Antioxidant and Melanogenesis Inhibitory Properties of Pracparatum Mungo (Lu-Do Huang

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Yu-Yu Kao

2013-07-01

Full Text Available Pracparatum mungo (Lu-Do Huang is a traditional Chinese functional medicine made from the natural fermentation of mung bean (綠豆 Lǜ Dòu mixed with other Chinese medicines. It has been recognized as having liver protecting and detoxifying effects. As mung beans have been verified to possess anti-inflammatory, antioxidant, antipyretic, and whitening actions, the present research utilized the in vitro, ex vivo, and in vivo experimental models to investigate the antioxidant and melanin inhibiting effects of P. mungo on the skin. The in vitro experiment revealed that P. mungo methanol extract (PMME and P. mungo ethanol extract (PMEE possess the capacity to clear α,α-diphenyl-2-picrylhydrazyl (DPPH radicals and inhibit tyrosinase activity. The ex vivo experiment indicated that PMEE can promote the growth of MDCK cells and increase the enzymatic activities of superoxide dismutase (SOD and catalase in MDCK cells. On the other hand, PMME and PMEE can suppress the proliferation of A375 cells, and PMEE can reduce the enzymatic activities of SOD and catalase in A375 cells. The in vivo results showed that P. mungo can enhance the enzymatic performance of SOD, Catalase, and glutathione peroxidase (GPx in the liver. The results also showed that P. mungo has antioxidant characteristics and can inhibit tyrosinase activity, thereby promoting the growth of skin tissues and suppressing the proliferation of A375 cells, and thus enhancing the effects that the antioxidant enzymatic performance has on the liver. These results can be applied in the development of tyrosinase inhibitors or antioxidants used for the inhibition of melanin biosynthesis or for auto-oxidation in further industrial applications, particularly those relating to functional food or cosmetic compositions.

Renoprotective effect of the antioxidant curcumin: Recent findings☆

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Trujillo, Joyce; Chirino, Yolanda Irasema; Molina-Jijón, Eduardo; Andérica-Romero, Ana Cristina; Tapia, Edilia; Pedraza-Chaverrí, José

2013-01-01

For years, there have been studies based on the use of natural compounds plant-derived as potential therapeutic agents for various diseases in humans. Curcumin is a phenolic compound extracted from Curcuma longa rhizome commonly used in Asia as a spice, pigment and additive. In traditional medicine of India and China, curcumin is considered as a therapeutic agent used in several foods. Numerous studies have shown that curcumin has broad biological functions particularly antioxidant and antiinflammatory. In fact, it has been established that curcumin is a bifunctional antioxidant; it exerts antioxidant activity in a direct and an indirect way by scavenging reactive oxygen species and inducing an antioxidant response, respectively. The renoprotective effect of curcumin has been evaluated in several experimental models including diabetic nephropathy, chronic renal failure, ischemia and reperfusion and nephrotoxicity induced by compounds such as gentamicin, adriamycin, chloroquine, iron nitrilotriacetate, sodium fluoride, hexavalent chromium and cisplatin. It has been shown recently in a model of chronic renal failure that curcumin exerts a therapeutic effect; in fact it reverts not only systemic alterations but also glomerular hemodynamic changes. Another recent finding shows that the renoprotective effect of curcumin is associated to preservation of function and redox balance of mitochondria. Taking together, these studies attribute the protective effect of curcumin in the kidney to the induction of the master regulator of antioxidant response nuclear factor erythroid-derived 2 (Nrf2), inhibition of mitochondrial dysfunction, attenuation of inflammatory response, preservation of antioxidant enzymes and prevention of oxidative stress. The information presented in this paper identifies curcumin as a promising renoprotective molecule against renal injury. PMID:24191240

Renoprotective effect of the antioxidant curcumin: Recent findings

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Joyce Trujillo

2013-01-01

Full Text Available For years, there have been studies based on the use of natural compounds plant-derived as potential therapeutic agents for various diseases in humans. Curcumin is a phenolic compound extracted from Curcuma longa rhizome commonly used in Asia as a spice, pigment and additive. In traditional medicine of India and China, curcumin is considered as a therapeutic agent used in several foods. Numerous studies have shown that curcumin has broad biological functions particularly antioxidant and antiinflammatory. In fact, it has been established that curcumin is a bifunctional antioxidant; it exerts antioxidant activity in a direct and an indirect way by scavenging reactive oxygen species and inducing an antioxidant response, respectively. The renoprotective effect of curcumin has been evaluated in several experimental models including diabetic nephropathy, chronic renal failure, ischemia and reperfusion and nephrotoxicity induced by compounds such as gentamicin, adriamycin, chloroquine, iron nitrilotriacetate, sodium fluoride, hexavalent chromium and cisplatin. It has been shown recently in a model of chronic renal failure that curcumin exerts a therapeutic effect; in fact it reverts not only systemic alterations but also glomerular hemodynamic changes. Another recent finding shows that the renoprotective effect of curcumin is associated to preservation of function and redox balance of mitochondria. Taking together, these studies attribute the protective effect of curcumin in the kidney to the induction of the master regulator of antioxidant response nuclear factor erythroid-derived 2 (Nrf2, inhibition of mitochondrial dysfunction, attenuation of inflammatory response, preservation of antioxidant enzymes and prevention of oxidative stress. The information presented in this paper identifies curcumin as a promising renoprotective molecule against renal injury.

Impacts of suppression on emotional responses and performance outcomes: an experience-sampling study in younger and older workers.

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Yeung, Dannii Y; Fung, Helene H

2012-11-01

Past studies have demonstrated that older adults used less emotional suppression to regulate their emotions than did younger adults, but the effectiveness of using this emotion regulatory strategy on psychosocial well-being across age remains largely unexplored. The present study adopted an experience-sampling method to examine whether the impacts of momentary employment of emotional suppression on momentary positive and negative emotions and job performance would be different by age. Eighty-seven Chinese insurance workers, aged between 18 and 61 years, participated in a 5-day sampling study. Their affective responses at work, momentary task performance, and sales productivity were recorded. Results showed that older workers' greater use of suppression at work was associated with lower intensity of negative emotions, whereas such association was not found among younger workers. Moreover, greater use of suppression over the sampling period was significantly predictive of sales productivity of older workers, but such a positive association was not shown in younger workers. These findings reveal that the use of suppression at work may be more effective for older workers than for younger workers.

Carnosine attenuates cyclophosphamide-induced bone marrow suppression by reducing oxidative DNA damage

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Jie Deng

2018-04-01

Full Text Available Oxidative DNA damage in bone marrow cells is the main side effect of chemotherapy drugs including cyclophosphamide (CTX. However, not all antioxidants are effective in inhibiting oxidative DNA damage. In this study, we report the beneficial effect of carnosine (β-alanyl-l-histidine, a special antioxidant with acrolein-sequestering ability, on CTX-induced bone marrow cell suppression. Our results show that carnosine treatment (100 and 200 mg/kg, i.p. significantly inhibited the generation of reactive oxygen species (ROS and 8-hydroxy-2′-deoxyguanosine (8-oxo-dG, and decreased chromosomal abnormalities in the bone marrow cells of mice treated with CTX (20 mg/kg, i.v., 24 h. Furthermore, carnosine evidently mitigated CTX-induced G2/M arrest in murine bone marrow cells, accompanied by reduced ratios of p-Chk1/Chk1 and p-p53/p53 as well as decreased p21 expression. In addition, cell apoptosis caused by CTX was also suppressed by carnosine treatment, as assessed by decreased TUNEL-positive cell counts, down-regulated expressions of Bax and Cyt c, and reduced ratios of cleaved Caspase-3/Caspase-3. These results together suggest that carnosine can protect murine bone marrow cells from CTX-induced DNA damage via its antioxidant activity. Keywords: Carnosine, Cyclophosphamide, Oxidative DNA damage, Sister chromatid exchange, Apoptosis, Cell cycle arrest

Suppressive effects of lysozyme on polyphosphate-mediated vascular inflammatory responses

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Chung, Jiwoo [College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics Based Creative Drug Research Team, Kyungpook National University, Daegu 41566 (Korea, Republic of); Ku, Sae-Kwang [Department of Anatomy and Histology, College of Korean Medicine, Daegu Haany University, Gyeongsan 38610 (Korea, Republic of); Lee, Suyeon [College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics Based Creative Drug Research Team, Kyungpook National University, Daegu 41566 (Korea, Republic of); Bae, Jong-Sup, E-mail: baejs@knu.ac.kr [College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics Based Creative Drug Research Team, Kyungpook National University, Daegu 41566 (Korea, Republic of)

2016-06-10

Lysozyme, found in relatively high concentration in blood, saliva, tears, and milk, protects us from the ever-present danger of bacterial infection. Previous studies have reported proinflammatory responses of endothelial cells to the release of polyphosphate(PolyP). In this study, we examined the anti-inflammatory responses and mechanisms of lysozyme and its effects on PolyP-induced septic activities in human umbilical vein endothelial cells (HUVECs) and mice. The survival rates, septic biomarker levels, behavior of human neutrophils, and vascular permeability were determined in PolyP-activated HUVECs and mice. Lysozyme suppressed the PolyP-mediated vascular barrier permeability, upregulation of inflammatory biomarkers, adhesion/migration of leukocytes, and activation and/or production of nuclear factor-κB, tumor necrosis factor-α, and interleukin-6. Furthermore, lysozyme demonstrated protective effects on PolyP-mediated lethal death and the levels of the related septic biomarkers. Therefore, these results indicated the therapeutic potential of lysozyme on various systemic inflammatory diseases, such as sepsis or septic shock. -- Highlights: •PolyP is shown to be an important mediator of vascular inflammation. •Lysozyme inhibited PolyP-mediated hyperpermeability. •Lysozyme inhibited PolyP-mediated septic response. •Lysozyme reduced PolyP-induced septic mortality.

Suppressive effects of lysozyme on polyphosphate-mediated vascular inflammatory responses

International Nuclear Information System (INIS)

Chung, Jiwoo; Ku, Sae-Kwang; Lee, Suyeon; Bae, Jong-Sup

2016-01-01

Lysozyme, found in relatively high concentration in blood, saliva, tears, and milk, protects us from the ever-present danger of bacterial infection. Previous studies have reported proinflammatory responses of endothelial cells to the release of polyphosphate(PolyP). In this study, we examined the anti-inflammatory responses and mechanisms of lysozyme and its effects on PolyP-induced septic activities in human umbilical vein endothelial cells (HUVECs) and mice. The survival rates, septic biomarker levels, behavior of human neutrophils, and vascular permeability were determined in PolyP-activated HUVECs and mice. Lysozyme suppressed the PolyP-mediated vascular barrier permeability, upregulation of inflammatory biomarkers, adhesion/migration of leukocytes, and activation and/or production of nuclear factor-κB, tumor necrosis factor-α, and interleukin-6. Furthermore, lysozyme demonstrated protective effects on PolyP-mediated lethal death and the levels of the related septic biomarkers. Therefore, these results indicated the therapeutic potential of lysozyme on various systemic inflammatory diseases, such as sepsis or septic shock. -- Highlights: •PolyP is shown to be an important mediator of vascular inflammation. •Lysozyme inhibited PolyP-mediated hyperpermeability. •Lysozyme inhibited PolyP-mediated septic response. •Lysozyme reduced PolyP-induced septic mortality.

Light history modulates antioxidant and photosynthetic responses of biofilms to both natural (light) and chemical (herbicides) stressors.

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Bonnineau, Chloé; Sague, Irene Gallardo; Urrea, Gemma; Guasch, Helena

2012-05-01

In multiple stress situations, the co-occurrence of environmental and chemical factors can influence organisms' ability to cope with toxicity. In this context, the influence of light adaptation on the response of freshwater biofilms to sudden light changes or to herbicides exposure was investigated by determining various parameters: diatom community composition, photosynthetic parameters, chlorophyll a content, antioxidant enzyme activities. Biofilms were grown in microcosms under sub-optimal, saturating, and high light intensities and showed already described characteristics of shade/light adaptation (community structure, photosynthetic adaptation, etc.). Light history modulated antioxidant and photosynthetic responses of biofilms to the stress caused by short-term exposure to sudden light changes or to herbicides. First biofilms adapted to sub-optimal light intensity (shade-adapted) were found to be more sensitive to an increase in light intensity than high-light adapted ones to a reduction in light intensity. Second, while light history influenced biofilms' response to glyphosate, it had little influence on biofilms' response to copper and none on its response to oxyfluorfen. Indeed glyphosate exposure led to a stronger decrease in photosynthetic efficiency of shade-adapted biofilms (EC(50) = 11.7 mg L(-1)) than of high-light adapted communities (EC(50) = 35.6 mg L(-1)). Copper exposure led to an activation of ascorbate peroxidase (APX) in biofilms adapted to sub-optimal and saturating light intensity while the protein content decreased in all biofilms exposed to copper. Oxyfluorfen toxicity was independent of light history provoking an increase in APX activity. In conclusion this study showed that both previous exposure to contaminants and physical habitat characteristics might influence community tolerance to disturbances strongly.

The suppression of manganese superoxide dismutase decreased the survival of human glioblastoma multiforme T98G cells

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Novi S. Hardiany

2017-05-01

Full Text Available Background: Glioblastoma multiforme (GBM is a primary malignant brain tumor which has poor prognosis. High incidence of oxidative stress-based therapy resistance could be related to the high antioxidant status of GBM cells. Our previous study has reported that manganese superoxide dismutase (MnSOD antioxidant expression was significantly higher in high grade glioma than in low grade. The aim of this study was to analyze the impact of MnSOD suppression toward GBM cell survival.Methods: This study is an experimental study using human glioblastoma multiforme T98G cell line. Suppression of MnSOD expression was performed using in vitro transfection MnSOD-siRNA. The MnSOD expression was analyzed by measuring the mRNA using real time RT-PCR, protein using ELISA technique, and specific activity of enzyme using inhibition of xantine oxidase. Concentration of reactive oxygen species (ROS intracellular was determined by measuring superoxide radical and hydrogen peroxide. Cell survival was analyzed by measuring viability, proliferation, and cell apoptosis.Results: In vitro transfection of MnSOD-siRNA suppressed the mRNA, protein, and specific activity of MnSOD. This treatment significantly increased the concentration of superoxide radical; however, it did not influence the concentration of hydrogen peroxide. Moreover, viability MnSOD-suppressing cell significantly decreased, accompanied by increase of cell apoptosis without affecting cell proliferation.Conclusion: The suppression of MnSOD expression leads to decrease glioblastoma multiforme cell survival, which was associated to the increase of cell apoptotic.

Growth, photosynthesis and antioxidant responses of endophyte infected and non-infected rice under lead stress conditions.

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Li, Xuemei; Bu, Ning; Li, Yueying; Ma, Lianju; Xin, Shigang; Zhang, Lihong

2012-04-30

An endophytic fungus was tested in rice (Oryza sativa L.) exposed to four levels of lead (Pb) stress (0, 50, 100 and 200 μM) to assess effects on plant growth, photosynthesis and antioxidant enzyme activity. Under Pb stress conditions, endophyte-infected seedlings had greater shoot length but lower root length compared to non-infected controls, and endophyte-infected seedlings had greater dry weight in the 50 and 100 μM Pb treatments. Under Pb stress conditions, chlorophyll and carotenoid levels were significantly higher in the endophyte-infected seedlings. Net photosynthetic rate, transpiration rate and water use efficiency were significantly higher in endophyte-infected seedlings in the 50 and 100 μM Pb treatments. In addition, chlorophyll fluorescence parameters Fv/Fm and Fv/Fo were higher in the infected seedlings compared to the non-infected seedlings under Pb stress. Malondialdehyde accumulation was induced by Pb stress, and it was present in higher concentration in non-infected seedlings under higher concentrations of Pb (100 and 200 μM). Antioxidant activity was either higher or unchanged in the infected seedlings due to responses to the different Pb concentrations. These results suggest that the endophytic fungus improved rice growth under moderate Pb levels by enhancing photosynthesis and antioxidant activity relative to non-infected rice. Copyright © 2012 Elsevier B.V. All rights reserved.

Antioxidant and Vasodilator Activity of Ugni molinae Turcz. (Murtilla and Its Modulatory Mechanism in Hypotensive Response

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Ignacio Jofré

2016-01-01

Full Text Available Hypertension is a systemic condition with high morbidity and mortality rates worldwide, which poses an increased risk for cardiovascular diseases. In this study, we demonstrated the antioxidant and vasodilator activity of Ugni molinae Turcz. (Murtilla fruit, a berry native to Chile and proposed models to explain its modulatory mechanism in hypotensive response. Murtilla fruits were cultivated in a germplasm bank and submitted to chemical and biological analyses. The phenolic compounds gallic acid, Catechin, Quercetin-3-β-D-glucoside, Myricetin, Quercetin, and Kaempferol were identified. Murtilla extract did not generate toxic effects on human endothelial cells and had significant antioxidant activity against ROS production, lipid peroxidation, and superoxide anion production. Furthermore, it showed dose-dependent vasodilator activity in aortic rings in the presence of endothelium, whose hypotensive mechanism is partially mediated by nitric oxide synthase/guanylate cyclase and large-conductance calcium-dependent potassium channels. Murtilla fruits might potentially have beneficial effects on the management of cardiovascular diseases.

Sulforaphane Inhibits Lipopolysaccharide-Induced Inflammation, Cytotoxicity, Oxidative Stress, and miR-155 Expression and Switches to Mox Phenotype through Activating Extracellular Signal-Regulated Kinase 1/2-Nuclear Factor Erythroid 2-Related Factor 2/Antioxidant Response Element Pathway in Murine Microglial Cells.

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Eren, Erden; Tufekci, Kemal Ugur; Isci, Kamer Burak; Tastan, Bora; Genc, Kursad; Genc, Sermin

2018-01-01

Sulforaphane (SFN) is a natural product with cytoprotective, anti-inflammatory, and antioxidant effects. In this study, we evaluated the mechanisms of its effects on lipopolysaccharide (LPS)-induced cell death, inflammation, oxidative stress, and polarization in murine microglia. We found that SFN protects N9 microglial cells upon LPS-induced cell death and suppresses LPS-induced levels of secreted pro-inflammatory cytokines, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-6. SFN is also a potent inducer of redox sensitive transcription factor, nuclear factor erythroid 2-related factor 2 (Nrf2), which is responsible for the transcription of antioxidant, cytoprotective, and anti-inflammatory genes. SFN induced translocation of Nrf2 to the nucleus via extracellular signal-regulated kinase 1/2 (ERK1/2) pathway activation. siRNA-mediated knockdown study showed that the effects of SFN on LPS-induced reactive oxygen species, reactive nitrogen species, and pro-inflammatory cytokine production and cell death are partly Nrf2 dependent. Mox phenotype is a novel microglial phenotype that has roles in oxidative stress responses. Our results suggested that SFN induced the Mox phenotype in murine microglia through Nrf2 pathway. SFN also alleviated LPS-induced expression of inflammatory microRNA, miR-155. Finally, SFN inhibits microglia-mediated neurotoxicity as demonstrated by conditioned medium and co-culture experiments. In conclusion, SFN exerts protective effects on microglia and modulates the microglial activation state.

A bacterial cysteine protease effector protein interferes with photosynthesis to suppress plant innate immune responses.

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Rodríguez-Herva, José J; González-Melendi, Pablo; Cuartas-Lanza, Raquel; Antúnez-Lamas, María; Río-Alvarez, Isabel; Li, Ziduo; López-Torrejón, Gema; Díaz, Isabel; Del Pozo, Juan C; Chakravarthy, Suma; Collmer, Alan; Rodríguez-Palenzuela, Pablo; López-Solanilla, Emilia

2012-05-01

The bacterial pathogen Pseudomonas syringae pv tomato DC3000 suppresses plant innate immunity with effector proteins injected by a type III secretion system (T3SS). The cysteine protease effector HopN1, which reduces the ability of DC3000 to elicit programmed cell death in non-host tobacco, was found to also suppress the production of defence-associated reactive oxygen species (ROS) and callose when delivered by Pseudomonas fluorescens heterologously expressing a P. syringae T3SS. Purified His(6) -tagged HopN1 was used to identify tomato PsbQ, a member of the oxygen evolving complex of photosystem II (PSII), as an interacting protein. HopN1 localized to chloroplasts and both degraded PsbQ and inhibited PSII activity in chloroplast preparations, whereas a HopN1(D299A) non-catalytic mutant lost these abilities. Gene silencing of NtPsbQ in tobacco compromised ROS production and programmed cell death by DC3000. Our data reveal PsbQ as a contributor to plant immunity responses and a target for pathogen suppression. © 2012 Blackwell Publishing Ltd.

Oxidative Stress and Antioxidant System in Periodontitis

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Wang, Yue; Andrukhov, Oleh; Rausch-Fan, Xiaohui

2017-01-01

Periodontitis is a common inflammatory disease, which is initiated by bacterial infection and subsequently progressed by aberrant host response. It can result in the destruction of teeth supporting tissues and have an influence on systemic health. When periodontitis occurs, reactive oxygen species, which are overproduced mostly by hyperactive neutrophils, could not be balanced by antioxidant defense system and cause tissues damage. This is characterized by increased metabolites of lipid peroxidation, DNA damage and protein damage. Local and systemic activities of antioxidants can also be influenced by periodontitis. Total antioxidant capacity, total oxidant status and oxidative stress index have been used to evaluate the oxidative stress associated with periodontitis. Studies have confirmed that inflammatory response in periodontitis is associated with an increased local and systemic oxidative stress and compromised antioxidant capacity. Our review focuses on increased oxidative stress in periodontal disease, specifically, on the relationship between the local and systemic biomarkers of oxidative stress and periodontitis and their association with the pathogenesis of periodontitis. Also, the relationship between periodontitis and systemic inflammation, and the effects of periodontal therapy on oxidative stress parameters will be discussed. PMID:29180965

Systemic depletion of L-cyst(e)ine with cyst(e)inase increases reactive oxygen species and suppresses tumor growth.

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Cramer, Shira L; Saha, Achinto; Liu, Jinyun; Tadi, Surendar; Tiziani, Stefano; Yan, Wupeng; Triplett, Kendra; Lamb, Candice; Alters, Susan E; Rowlinson, Scott; Zhang, Yan Jessie; Keating, Michael J; Huang, Peng; DiGiovanni, John; Georgiou, George; Stone, Everett

2017-01-01

Cancer cells experience higher oxidative stress from reactive oxygen species (ROS) than do non-malignant cells because of genetic alterations and abnormal growth; as a result, maintenance of the antioxidant glutathione (GSH) is essential for their survival and proliferation. Under conditions of elevated ROS, endogenous L-cysteine (L-Cys) production is insufficient for GSH synthesis. This necessitates uptake of L-Cys that is predominantly in its disulfide form, L-cystine (CSSC), via the xCT(-) transporter. We show that administration of an engineered and pharmacologically optimized human cyst(e)inase enzyme mediates sustained depletion of the extracellular L-Cys and CSSC pool in mice and non-human primates. Treatment with this enzyme selectively causes cell cycle arrest and death in cancer cells due to depletion of intracellular GSH and ensuing elevated ROS; yet this treatment results in no apparent toxicities in mice even after months of continuous treatment. Cyst(e)inase suppressed the growth of prostate carcinoma allografts, reduced tumor growth in both prostate and breast cancer xenografts and doubled the median survival time of TCL1-Tg:p53 -/- mice, which develop disease resembling human chronic lymphocytic leukemia. It was observed that enzyme-mediated depletion of the serum L-Cys and CSSC pool suppresses the growth of multiple tumors, yet is very well tolerated for prolonged periods, suggesting that cyst(e)inase represents a safe and effective therapeutic modality for inactivating antioxidant cellular responses in a wide range of malignancies.

The Seed Repair Response during Germination: Disclosing Correlations between DNA Repair, Antioxidant Response, and Chromatin Remodeling in Medicago truncatula

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Andrea Pagano

2017-11-01

Full Text Available This work provides novel insights into the effects caused by the histone deacetylase inhibitor trichostatin A (TSA during Medicago truncatula seed germination, with emphasis on the seed repair response. Seeds treated with H2O and TSA (10 and 20 μM were collected during imbibition (8 h and at the radicle protrusion phase. Biometric data showed delayed germination and impaired seedling growth in TSA-treated samples. Comet assay, performed on radicles at the protrusion phase and 4-days old M. truncatula seedlings, revealed accumulation of DNA strand breaks upon exposure to TSA. Activation of DNA repair toward TSA-mediated genotoxic damage was evidenced by the up-regulation of MtOGG1(8-OXOGUANINE GLYCOSYLASE/LYASE gene involved in the removal of oxidative DNA lesions, MtLIGIV(LIGASE IV gene, a key determinant of seed quality, required for the rejoining of DNA double strand breaks and TDP(TYROSYL-DNA PHOSPHODIESTERASE genes encoding the multipurpose DNA repair enzymes tyrosyl-DNA phosphodiesterases. Since radical scavenging can prevent DNA damage, the specific antioxidant activity (SAA was measured by DPPH (1,1-diphenyl-2-picrylhydrazyl and Folin-Ciocalteu reagent assays. Fluctuations of SAA were observed in TSA-treated seeds/seedlings concomitant with the up-regulation of antioxidant genes MtSOD(SUPEROXIDE DISMUTASE, MtAPX(ASCORBATE PEROXIDASE and MtMT2(TYPE 2 METALLOTHIONEIN. Chromatin remodeling, required to facilitate the access of DNA repair enzymes at the damaged sites, is also part of the multifaceted seed repair response. To address this aspect, still poorly explored in plants, the MtTRRAP(TRANSFORMATION/TRANSACTIVATION DOMAIN-ASSOCIATED PROTEIN gene was analyzed. TRRAP is a transcriptional adaptor, so far characterized only in human cells where it is needed for the recruitment of histone acetyltransferase complexes to chromatin during DNA repair. The MtTRRAP gene and the predicted interacting partners MtHAM2 (HISTONE ACETYLTRANSFERASE OF

Trichoderma-Plant Root Colonization: Escaping Early Plant Defense Responses and Activation of the Antioxidant Machinery for Saline Stress Tolerance

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Brotman, Yariv; Landau, Udi; Cuadros-Inostroza, Álvaro; Takayuki, Tohge; Fernie, Alisdair R.; Chet, Ilan; Viterbo, Ada; Willmitzer, Lothar

2013-01-01

Trichoderma spp. are versatile opportunistic plant symbionts which can colonize the apoplast of plant roots. Microarrays analysis of Arabidopsis thaliana roots inoculated with Trichoderma asperelloides T203, coupled with qPCR analysis of 137 stress responsive genes and transcription factors, revealed wide gene transcript reprogramming, proceeded by a transient repression of the plant immune responses supposedly to allow root colonization. Enhancement in the expression of WRKY18 and WRKY40, which stimulate JA-signaling via suppression of JAZ repressors and negatively regulate the expression of the defense genes FMO1, PAD3 and CYP71A13, was detected in Arabidopsis roots upon Trichoderma colonization. Reduced root colonization was observed in the wrky18/wrky40 double mutant line, while partial phenotypic complementation was achieved by over-expressing WRKY40 in the wrky18 wrky40 background. On the other hand increased colonization rate was found in roots of the FMO1 knockout mutant. Trichoderma spp. stimulate plant growth and resistance to a wide range of adverse environmental conditions. Arabidopsis and cucumber (Cucumis sativus L.) plants treated with Trichoderma prior to salt stress imposition show significantly improved seed germination. In addition, Trichoderma treatment affects the expression of several genes related to osmo-protection and general oxidative stress in roots of both plants. The MDAR gene coding for monodehydroascorbate reductase is significantly up-regulated and, accordingly, the pool of reduced ascorbic acid was found to be increased in Trichoderma treated plants. 1-Aminocyclopropane-1-carboxylate (ACC)-deaminase silenced Trichoderma mutants were less effective in providing tolerance to salt stress, suggesting that Trichoderma, similarly to ACC deaminase producing bacteria, can ameliorate plant growth under conditions of abiotic stress, by lowering ameliorating increases in ethylene levels as well as promoting an elevated antioxidative capacity

Ganglioside GM1 protects against high altitude cerebral edema in rats by suppressing the oxidative stress and inflammatory response via the PI3K/AKT-Nrf2 pathway.

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Gong, Gu; Yin, Liang; Yuan, Libang; Sui, Daming; Sun, Yangyang; Fu, Haiyu; Chen, Liang; Wang, Xiaowu

2018-03-01

High altitude cerebral edema (HACE) is a severe type of acute mountain sickness (AMS) that occurs in response to a high altitude hypobaric hypoxic (HH) environment. GM1 monosialoganglioside can alleviate brain injury under adverse conditions including amyloid-β-peptide, ischemia and trauma. However, its role in HACE-induced brain damage remains poorly elucidated. In this study, GM1 supplementation dose-dependently attenuated increase in rat brain water content (BWC) induced by hypobaric chamber (7600 m) exposurefor 24 h. Compared with the HH-treated group, rats injected with GM1 exhibited less brain vascular leakage, lower aquaporin-4 and higher occludin expression, but they also showed increase in Na+/K+-ATPase pump activities. Importantly, HH-incurred consciousness impairment and coordination loss also were ameliorated following GM1 administration. Furthermore, the increased oxidative stress and decrease in anti-oxidant stress system under the HH condition were also reversely abrogated by GM1 treatment via suppressing accumulation of ROS, MDA and elevating the levels of SOD and GSH. Simultaneously, GM1 administration also counteracted the enhanced inflammation in HH-exposed rats by muting pro-inflammatory cytokines IL-1β, TNF-α, and IL-6 levels in serum and brain tissues. Subsequently, GM1 potentiated the activation of the PI3K/AKT-Nrf2 pathway. Cessation of this pathway by LY294002 reversed GM1-mediated inhibitory effects on oxidative stress and inflammation, and ultimately abrogated the protective role of GM1 in abating brain edema, cognitive and motor dysfunction. Overall, GM1 may afford a protective intervention in HACE by suppressing oxidative stress and inflammatory response via activating the PI3K/AKT-Nrf2 pathway, implying a promising agent for the treatment of HACE. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hepatitis C Virus Frameshift/Alternate Reading Frame Protein Suppresses Interferon Responses Mediated by Pattern Recognition Receptor Retinoic-Acid-Inducible Gene-I.

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Seung Bum Park

Full Text Available Hepatitis C virus (HCV actively evades host interferon (IFN responses but the mechanisms of how it does so are not completely understood. In this study, we present evidence for an HCV factor that contributes to the suppression of retinoic-acid-inducible gene-I (RIG-I-mediated IFN induction. Expression of frameshift/alternate reading frame protein (F/ARFP from HCV -2/+1 frame in Huh7 hepatoma cells suppressed type I IFN responses stimulated by HCV RNA pathogen-associated molecular pattern (PAMP and poly(IC. The suppression occurred independently of other HCV factors; and activation of interferon stimulated genes, TNFα, IFN-λ1, and IFN-λ2/3 was likewise suppressed by HCV F/ARFP. Point mutations in the full-length HCV sequence (JFH1 genotype 2a strain were made to introduce premature termination codons in the -2/+1 reading frame coding for F/ARFP while preserving the original reading frame, which enhanced IFNα and IFNβ induction by HCV. The potentiation of IFN response by the F/ARFP mutations was diminished in Huh7.5 cells, which already have a defective RIG-I, and by decreasing RIG-I expression in Huh7 cells. Furthermore, adding F/ARFP back via trans-complementation suppressed IFN induction in the F/ARFP mutant. The F/ARFP mutants, on the other hand, were not resistant to exogenous IFNα. Finally, HCV-infected human liver samples showed significant F/ARFP antibody reactivity, compared to HCV-uninfected control livers. Therefore, HCV F/ARFP likely cooperates with other viral factors to suppress type I and III IFN induction occurring through the RIG-I signaling pathway. This study identifies a novel mechanism of pattern recognition receptor modulation by HCV and suggests a biological function of the HCV alternate reading frame in the modulation of host innate immunity.

Rice homeobox transcription factor HOX1a positively regulates gibberellin responses by directly suppressing EL1.

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Wen, Bi-Qing; Xing, Mei-Qing; Zhang, Hua; Dai, Cheng; Xue, Hong-Wei

2011-11-01

Homeobox transcription factors are involved in various aspects of plant development, including maintenance of the biosynthesis and signaling pathways of different hormones. However, few direct targets of homeobox proteins have been identified. We here show that overexpression of rice homeobox gene HOX1a resulted in enhanced gibberellin (GA) response, indicating a positive effect of HOX1a in GA signaling. HOX1a is induced by GA and encodes a homeobox transcription factor with transcription repression activity. In addition, HOX1a suppresses the transcription of early flowering1 (EL1), a negative regulator of GA signaling, and further electrophoretic mobility shift assay and chromatin immunoprecipitation analysis revealed that HOX1a directly bound to the promoter region of EL1 to suppress its expression and stimulate GA signaling. These results demonstrate that HOX1a functions as a positive regulator of GA signaling by suppressing EL1, providing informative hints on the study of GA signaling. © 2011 Institute of Botany, Chinese Academy of Sciences.

Aloin Suppresses Lipopolysaccharide-Induced Inflammatory Response and Apoptosis by Inhibiting the Activation of NF-κB

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Xuan Luo

2018-02-01

Full Text Available Numerous herbal-derived natural products are excellent anti-inflammatory agents. Several studies have reported that aloin, the major anthraquinone glycoside obtained from the Aloe species, exhibits anti-inflammatory activity. However, the molecular mechanism of this activity is not well understood. In this report, we found that aloin suppresses lipopolysaccharide-induced pro-inflammatory cytokine secretion and nitric oxide production, and downregulates the expression of tumor necrosis factor alpha (TNF-α, interleukin 6 (IL-6, inducible nitric oxide synthase (iNOS, and cyclooxygenase-2 (COX-2. Aloin inhibits the phosphorylation and acetylation of the NF-κB p65 subunit by suppressing the upstream kinases p38 and Msk1, preventing LPS-induced p65 translocation to the nucleus. We have also shown that aloin inhibits LPS-induced caspase-3 activation and apoptotic cell death. Collectively, these findings suggest that aloin effectively suppresses the inflammatory response, primarily through the inhibition of NF-κB signaling.

Antioxidant airway responses following experimental exposure to wood smoke in man

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Sehlstedt Maria

2010-08-01

Full Text Available Abstract Background Biomass combustion contributes to the production of ambient particulate matter (PM in rural environments as well as urban settings, but relatively little is known about the health effects of these emissions. The aim of this study was therefore to characterize airway responses in humans exposed to wood smoke PM under controlled conditions. Nineteen healthy volunteers were exposed to both wood smoke, at a particulate matter (PM2.5 concentration of 224 ± 22 μg/m3, and filtered air for three hours with intermittent exercise. The wood smoke was generated employing an experimental set-up with an adjustable wood pellet boiler system under incomplete combustion. Symptoms, lung function, and exhaled NO were measured over exposures, with bronchoscopy performed 24 h post-exposure for characterisation of airway inflammatory and antioxidant responses in airway lavages. Results Glutathione (GSH concentrations were enhanced in bronchoalveolar lavage (BAL after wood smoke exposure vs. air (p = 0.025, together with an increase in upper airway symptoms. Neither lung function, exhaled NO nor systemic nor airway inflammatory parameters in BAL and bronchial mucosal biopsies were significantly affected. Conclusions Exposure of healthy subjects to wood smoke, derived from an experimental wood pellet boiler operating under incomplete combustion conditions with PM emissions dominated by organic matter, caused an increase in mucosal symptoms and GSH in the alveolar respiratory tract lining fluids but no acute airway inflammatory responses. We contend that this response reflects a mobilisation of GSH to the air-lung interface, consistent with a protective adaptation to the investigated wood smoke exposure.

Antioxidant Potential of Selected Korean Edible Plant Extracts

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Yaejin Woo

2017-01-01

Full Text Available This study aimed to evaluate the antioxidant activity of various plant extracts. A total of 94 kinds of edible plant extracts obtained from the Korea Plant Extract Bank were screened for cytotoxicity, following which the total phenolic content of 24 shortlisted extracts was determined. Of these, extracts from three plants, namely, Castanea crenata (CC leaf, Camellia japonica (CJ fruit, and Viburnum dilatatum (VD leaf, were examined for antioxidant capabilities by measuring radical scavenging activity, ferric reducing/antioxidant power, and lipid peroxidation inhibitory activity. In addition, cellular antioxidant activities of the three extracts were assessed by a cell-based dichlorofluorescein assay and antioxidant response element (ARE reporter activity assay. The results demonstrated that all three extracts concentration-dependently scavenged free radicals, inhibited lipid peroxidation, reduced the cellular level of reactive oxygen species, and increased ARE-luciferase activity, indicating antioxidant enzyme-inducing potential. In particular, CJ extract showed significantly greater antioxidative activity and antimigratory effect in a breast cancer cell line compared to CC and VD extracts. Hence, CJ extract deserves further study for its in vivo functionality or biologically active constituents.

Serum Oxidative Stress Markers and Lipidomic Profile to Detect NASH Patients Responsive to an Antioxidant Treatment: A Pilot Study

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Paola Stiuso

2014-01-01

Full Text Available Liver steatosis can evolve to steatohepatitis (NASH through a series of biochemical steps related to oxidative stress in hepatocytes. Antioxidants, such as silybin, have been proposed as a treatment of patients with nonalcoholic fatty liver disease (NAFLD and NASH. In this study, we evaluated, in patients with histologically documented NASH, the oxidant/antioxidant status and lipid “fingerprint” in the serum of NASH patients, both in basal conditions and after 12 months of treatment with silybin-based food integrator Realsil (RA. The oxidant/antioxidant status analysis showed the presence of a group of patients with higher basal severity of disease (NAS scores 4.67 ± 2.5 and a second group corresponding to borderline NASH (NAS scores = 3.8 ± 1.5. The chronic treatment with RA changed the NAS score in both groups that reached the statistical significance only in group 2, in which there was also a significant decrease of serum lipid peroxidation. The lipidomic profile showed a lipid composition similar to that of healthy subjects with a restoration of the values of free cholesterol, lysoPC, SM, and PC only in group 2 of patients after treatment with RA. Conclusion. These data suggest that lipidomic and/or oxidative status of serum from patients with NASH could be useful as prognostic markers of response to an antioxidant treatment.

One-week acid suppression trial in uninvestigated dyspepsia patients with epigastric pain or burning to predict response to 8 weeks' treatment with esomeprazole

DEFF Research Database (Denmark)

van Zanten, S V; Flook, N; Talley, N J

2007-01-01

BACKGROUND: While empiric acid-suppressive therapy for uninvestigated dyspepsia patients with symptoms of epigastric pain or burning is standard practice, it is unknown whether an early response to therapy predicts outcome. AIM: To evaluate whether a 1-w acid suppression trial is effective...... for predicting 8-w response in such patients. METHODS: Helicobacter pylori-negative patients (aged 18-50 years) in primary care with uninvestigated epigastric pain or burning were randomized to esomeprazole 40 mg q.d.s. or b.d. for 1w, followed by esomeprazole 40 mg q.d.s. or placebo for 7w. Each day, patients......, respectively, and 47% (339 of 716) and 34% (124 of 368), respectively, at 8w (both P treatment were 58% and 70%, respectively, at 8w. CONCLUSION: A 1-w acid suppression trial is of limited clinical value for predicting 8-w response...

Transcriptome analysis of Carica papaya embryogenic callus upon De-etiolated 1 (DET1 gene suppression

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Diyana Jamaluddin

2017-06-01

Full Text Available Papaya is considered to be one of the most nutritional fruits. It is rich in vitamins, carotenoids, flavonoids and other phytonutrient which function as antioxidant in our body [1]. Previous studies revealed that the suppression of a negative regulator gene in photomorphogenesis, De-etiolated 1 (DET1 can improve the phytonutrient in tomato and canola without affecting the fruit quality [2,3]. This report contains the experimental data on high-throughput 3′ mRNA sequencing of transformed papaya callus upon DET1 gene suppression.

Optimization of Preparation of Antioxidative Peptides from Pumpkin Seeds Using Response Surface Method

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Fan, Sanhong; Hu, Yanan; Li, Chen; Liu, Yanrong

2014-01-01

Protein isolates of pumpkin (Cucurbita pepo L) seeds were hydrolyzed by acid protease to prepare antioxidative peptides. The hydrolysis conditions were optimized through Box-Behnken experimental design combined with response surface method (RSM). The second-order model, developed for the DPPH radical scavenging activity of pumpkin seed hydrolysates, showed good fit with the experiment data with a high value of coefficient of determination (0.9918). The optimal hydrolysis conditions were determined as follows: hydrolyzing temperature 50°C, pH 2.5, enzyme amount 6000 U/g, substrate concentration 0.05 g/ml and hydrolyzing time 5 h. Under the above conditions, the scavenging activity of DPPH radical was as high as 92.82%. PMID:24637721

A High Antioxidant Spice Blend Attenuates Postprandial Insulin and Triglyceride Responses and Increases Some Plasma Measures of Antioxidant Activity in Healthy, Overweight Men123

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Skulas-Ray, Ann C.; Kris-Etherton, Penny M.; Teeter, Danette L.; Chen, C-Y. Oliver; Vanden Heuvel, John P.; West, Sheila G.

2011-01-01

There is much interest in the potential of dietary antioxidants to attenuate in vivo oxidative stress, but little characterization of the time course of plasma effects exists. Culinary spices have demonstrated potent in vitro antioxidant properties. The objective of this study was to examine whether adding 14 g of a high antioxidant spice blend to a 5060-kJ (1200 kcal) meal exerted significant postprandial effects on markers of plasma antioxidant status and metabolism. Healthy overweight men (n = 6) consumed a control and spiced meal in a randomized crossover design with 1 wk between testing sessions. Blood was sampled prior to the meal and at 30-min intervals for 3.5 h (total of 8 samples). Mixed linear models demonstrated a treatment × time interaction (P spiced meal, respectively. Adding spices to the meal significantly increased the ferric reducing antioxidant power, such that postprandial increases following the spiced meal were 2-fold greater than after the control meal (P = 0.009). The hydrophilic oxygen radical absorbance capacity (ORAC) of plasma also was increased by spices (P = 0.02). There were no treatment differences in glucose, total thiols, lipophilic ORAC, or total ORAC. The incorporation of spices into the diet may help normalize postprandial insulin and TG and enhance antioxidant defenses. PMID:21697300

Antioxidants

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Antioxidants are man-made or natural substances that may prevent or delay some types of cell damage. Antioxidants are found in many foods, including fruits and ... are also available as dietary supplements. Examples of antioxidants include Beta-carotene Lutein Lycopene Selenium Vitamin A ...

Differential Antioxidative Responses to Water Deficit Among four Barley (Hordeum vulgare L. Genotypes

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Z Amini

2013-08-01

Full Text Available Future climate changes are expected to increase risks of drought, which already represent the most common stress factor for stable barley (Hordeum vulgare L. production in Iran. Up to now, extensive research projects have been done to study effects of drought stress on the antioxidant enzyme activity. While there is a few works of such studies on the field condition. In order to study of water deficit effects on the antioxidant enzymes activities as a secondary stress, we evaluate the effects of mild and severe drought stress on activities of antioxidative enzymes including superoxide dismutases, ascorbate peroxidase, catalase and peroxidase, among four barley genotypes, differing in the capacity to maintain the grain yield under drought condition during beginning on anthesis, kernel watery ripe and late milk stages under field condition. Results showed that drought increased the activity of antioxidant enzymes in all genotypes. At beginning of anthesis, POX activity of Q22 was higher than it in other genotypes ( P

The optimization of extraction of antioxidants from apple pomace by pressurized liquids.

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Wijngaard, Hilde; Brunton, Nigel

2009-11-25

Pressurized liquid extraction (PLE) is a green extraction technique that can enhance extraction rates of bioactive compounds. PLE was used to extract antioxidants and polyphenols from industrially generated apple pomace at two different temperature ranges: 160 to 193 degrees C and 75 to 125 degrees C. Antioxidant activity (DPPH radical scavenging test), total phenol content and three individual polyphenol groups were determined. Response surface methodology was used to optimize the five response values. Maximum antioxidant activity was obtained at a temperature of 200 degrees C, but unwanted compounds such as hydroxymethylfurfural were formed. Therefore a lower temperature range between 75 and 125 degrees C is recommended. Using this temperature range, a maximum antioxidant activity was determined at 60% ethanol and 102 degrees C. By using PLE the antioxidant activity was increased 2.4 times in comparison to traditional solid-liquid extraction, and the technique may be a promising alternative to conventional techniques for extracting antioxidants.

Effect of tributyltin on antioxidant ability and immune responses of zebrafish (Danio rerio).

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Zhang, Chun-Nuan; Zhang, Ji-Liang; Ren, Hong-Tao; Zhou, Bian-Hua; Wu, Qiu-Jue; Sun, Ping

2017-04-01

Tributyltin (TBT) is a toxic compound released into aquatic ecosystems through antifouling paints. This study was designed to examine the effects of TBT on antioxidant ability and immune responses of zebrafish (Danio rerio). Three hundred sixty healthy zebrafish were randomly grouped into four groups and exposed to different doses of TBT (0, 1, 10 and 100ngL -1 ). At the end of 8 weeks, the fish were sampled, and antioxidant capability, immune parameters and immune-related genes were assessed. The results showed that with an increase in TBT dose, the concentration of malonaldehyde in the liver was significantly increased (p<0.05), whereas the activities of total superoxide dismutase, catalase and glutathione peroxidase were significantly decreased (p<0.05) compared to the control. The activity and expression of lysozyme and the content of immunoglobulin M were significantly decreased compared to those of the fish exposed to 0ngL -1 TBT (p<0.05). However, the expression of the HSP70, HSP90, tumor necrosis factor-α(TNF-α), interleukins (IL-1β, IL-6), and nuclear factor-kappa B p65 (NF-κ B p65) genes were all enhanced with an increase in TBT dose. The results indicated that TBT induced oxidative stress and had immunotoxic effects on zebrafish. Copyright © 2016 Elsevier Inc. All rights reserved.

The responses of antioxidant system in bitter melon, sponge gourd, and winter squash under flooding and chilling stresses

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Do, Tuong Ha; Nguyen, Hoang Chinh; Lin, Kuan-Hung

2018-04-01

The objective of this paper was to review the responses of antioxidant system and physiological parameters of bitter melon (BM), sponge gourd (SG), and winter squash (WS) under waterlogged and low temperature conditions. The BM and SG plants were subjected to 0-72 h flooding treatments, and BM and WS plants were exposed to chilling at 12/7 °C (day/night) for 0-72 h. Different genotypes responded differently to environmental stress according to their various antioxidant system and physiological parameters. Increased ascorbate peroxidase (APX) and superoxide dismutase (SOD) activities provided SG and WS plants with increased waterlogging and chilling stress tolerance, respectively, compared to BM plants. The APX gene from SG and the SOD gene from WS were then cloned, and the regulation of APX and SOD gene expressions under flooding and chilling stress, respectively, were also measured. Increased expression of APX and SOD genes was accompanied by the increased activity of the enzyme involved in detoxifying reactive oxygen species (ROS) in response to those stresses. Both APX and SOD activities can be used for selecting BM lines with the best tolerances to water logging and chilling stresses.

Degree of suppression of associations to stages of addiction by the response of "high".

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Haertzen, C A; Ross, F E

1980-05-01

Male heroin or opiate addicts (N = 78) had a great inclination to give the association "to be high" to the names of nine drugs of abuse in a multiple-forced-choice association test irrespective of whether they had weak or strong habits for the drugs used as stimulus words. The tendency to give the "high" response was so great that other responses indicative of stages of addiction, steps in drug-taking, or drug effects were suppressed below the chance level. When scales were scored so that the response of "high" had no effect, the habit status of the sample revealed by associations with a specific set of words became clearer. A pattern of a strong habit for opiates evoked by opiate names became more evident after elimination of the effect of the response to "high," as did the strong habit pattern in response to drug relevant words. However, the pattern of responses characteristic of a nonaddictive status evoked by clean words remained relatively stable even including the effect of the response of "high." The study suggests that more meaningful responses are found when the response options are multiple rather than fixed.

Nitrosonifedipine ameliorates the progression of type 2 diabetic nephropathy by exerting antioxidative effects.

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Keisuke Ishizawa

Full Text Available Diabetic nephropathy (DN is the major cause of end-stage renal failure. Oxidative stress is implicated in the pathogenesis of DN. Nitrosonifedipine (NO-NIF is a weak calcium channel blocker that is converted from nifedipine under light exposure. Recently, we reported that NO-NIF has potential as a novel antioxidant with radical scavenging abilities and has the capacity to treat vascular dysfunction by exerting an endothelial protective effect. In the present study, we extended these findings by evaluating the efficacy of NO-NIF against DN and by clarifying the mechanisms of its antioxidative effect. In a model of type 2 DN (established in KKAy mice, NO-NIF administration reduced albuminuria and proteinuria as well as glomerular expansion without affecting glucose metabolism or systolic blood pressure. NO-NIF also suppressed renal and systemic oxidative stress and decreased the expression of intercellular adhesion molecule (ICAM-1, a marker of endothelial cell injury, in the glomeruli of the KKAy mice. Similarly, NO-NIF reduced albuminuria, oxidative stress, and ICAM-1 expression in endothelial nitric oxide synthase (eNOS knockout mice. Moreover, NO-NIF suppressed urinary angiotensinogen (AGT excretion and intrarenal AGT protein expression in proximal tubular cells in the KKAy mice. On the other hand, hyperglycemia-induced mitochondrial superoxide production was not attenuated by NO-NIF in cultured endothelial cells. These findings suggest that NO-NIF prevents the progression of type 2 DN associated with endothelial dysfunction through selective antioxidative effects.

Influence of animal age upon antioxidant-modified UV carcinogenesis

Energy Technology Data Exchange (ETDEWEB)

Black, H S [Photobiology Laboratory, Veterans Administration Medical Center, Houston, TX (USA); McCann, V [Baylor Univ., Houston, TX (USA). Coll. of Medicine; Thornby, J I [Biostatistics Section, Research Service, Veterans Administration Medical Center, Houston, TX (USA)

1982-08-01

Studies were undertaken to examine the effects of animal age on the anticarcinogenic properties of antioxidants. Female hairless mice, 2.5, 4.5 and 9.5 months of age, were subjected to daily irradiation from Westinghouse BZS-WLG lamps for 19 weeks. Experimental groups of animals were maintained on a commercial rodent meal supplemented with a 2% (w/w) antioxidant mixture. Control groups received only the meal. Tumour latency, expressed as median time to tumor development, was significantly greater for all age groups receiving antioxidants than for their similarly aged controls. However, the response to antioxidants appeared to decrease with age and the antioxidant effect was significantly less in the 9.5 month-old group than in the 2.5 month-old group. Likewise, the two youngest groups receiving antioxidants demonstrated a significantly fewer number of tumors per animal. It is concluded that animal age influences the degree of photoprotection provided by antioxidants. Whether this effect is related to dietary intake, and thus dependent upon resident antioxidant levels, is unknown. Nevertheless, dietary antioxidants provide significant protection in young animals against carcinogenesis induced by radiation of predominantly UVB wavelengths.

Antioxidant and enzymatic responses to oxidative stress induced by pre-harvest water supply reduction and ripening on mango (Mangifera indica L. cv. 'Cogshall') in relation to carotenoid content.

Science.gov (United States)

Rosalie, Rémy; Joas, Jacques; Deytieux-Belleau, Christelle; Vulcain, Emmanuelle; Payet, Bertrand; Dufossé, Laurent; Léchaudel, Mathieu

2015-07-20

The effects of a reduction in water supply during fruit development and postharvest fruit ripening on the oxidative status and the antioxidant defense system were studied in the mango fruit (Mangifera indica L.) cv. Cogshall. Changes in non-enzymatic (ascorbate) and enzymatic (SOD, CAT, APX, MDHAR, DHAR and GR) antioxidants, as well as oxidative parameters (H2O2 and MDA) and major carotenoids, were measured in unripe and ripe fruits from well-irrigated and non-irrigated trees. Under non-limiting water supply conditions, ripening induced oxidation as a result of the production of ROS and decreased ascorbate content. Antioxidant enzymatic systems were activated to protect fruit tissues and to regenerate the ascorbate pool. The carotenoid pool, mainly represented by β-carotene and esterified violaxanthine isomers, accumulated naturally during mango ripening. The suppression of irrigation decreased fruit size and induced accumulation of ABA and of its storage form, ABA-GE, in fruit pulp from the earliest harvest. It also increased oxidation, which was observable by the high levels of ascorbate measured at the early stages at harvest, and by the delay in the time it took to reach the pseudo constant carotene-to-xanthophyll ratio in ripe fruits. Nevertheless, differences between the irrigation treatments on the antioxidant system in ripe fruits were not significant, mainly because of the drastic changes in this system during ripening. Copyright © 2015 Elsevier GmbH. All rights reserved.

Feed supplementation with arginine and zinc on antioxidant status and inflammatory response in challenged weanling piglets

Directory of Open Access Journals (Sweden)

Nadia Bergeron

2017-09-01

Full Text Available Although supplementing the diet with zinc oxide and arginine is known to improve growth in weanling piglets, the mechanism of action is not well understood. We measured the antioxidant status and inflammatory response in 48 weanling castrated male piglets fed diets supplemented with or without zinc oxide (2,500 mg Zn oxide per kg and arginine (1% starting at the age of 20 days. The animals were injected with lipopolysaccharide (100 μg/kg on day 5. Half of them received another injection on day 12. Blood samples were taken just before and 6, 24 and 48 h after injection and the mucosa lining the ileum was recovered following euthanizing on days 7 and 14. Zinc supplementation increased reduced and total glutathione (GSH (reduced and total during days 5 to 7 and arginine decreased oxidized GSH measured on days 5 and 12 and the ratio of total antioxidant capacity to total oxidative status during days 12 to 14. Zinc decreased plasma malondialdehyde measured on days 5 and 12 and serum haptoglobin measured on day 12 and increased both metallothionein-1 expression and total antioxidant capacity measured in the ileal mucosa on day 14. Tumour necrosis factor α concentration decreased from days 5 to 12 (all effects were significant at P < 0.05. This study shows that the zinc supplement reduced lipid oxidation and lipopolysaccharide-induced inflammation during the post-weaning period, while the arginine supplementation had only a limited effect.

Metallothionein-mediated antioxidant defense system and its response to exercise training are impaired in human type 2 diabetes

DEFF Research Database (Denmark)

Scheede-Bergdahl, Celena; Penkowa, Milena; Hidalgo, Juan

2005-01-01

lower levels of MT-I+II were also detected in the plasma of type 2 diabetic subjects compared with control subjects. These results suggest that, in control subjects, the MT-I+II defense system is active and inducible within skeletal muscle tissue and plasma. In type 2 diabetes, reduced levels of MT......Oxidative stress is implicated in diabetes complications, during which endogenous antioxidant defenses have important pathophysiological consequences. To date, the significance of endogenous antioxidants such as metallothioneins I and II (MT-I+II) in type 2 diabetes remains unclear. To examine....... Immunohistochemical analysis revealed reduced MT-I+II levels in the skeletal muscle of type 2 diabetic subjects compared with control subjects. Control subjects produced a robust increase of MT-I+II in response to training; however, in type 2 diabetes, MT-I+II levels remained essentially unchanged. Significantly...

Response of antioxidant system to drought stress and re-watering in Alfalfa during branching

Science.gov (United States)

Tina, R. R.; Shan, X. R.; Wang, Y.; Guo, S. Y.; Mao, B.; Wang, W.; Wu, H. Y.; Zhao, T. H.

2017-11-01

This paper aimed to reveal the response mechanism of active oxygen metabolism and antioxidant enzyme activities in Alfalfa under drought stress and re-watering, and the pot experiment was used, to explore the changes of H2O2, O2·-, electrolyte leakage conductivity and MDA, SOD, POD, CAT activity in Golden Empress (tolerant cultivar) and Sanditi (non-tolerant cultivar) under drought stress and re-watering during branching stage. Three water gradients were set up: CK (Maximum field capacity of 75%±5%), T1 (Maximum field capacity of 45%±5%), T2 (Maximum field capacity of 35%±5%) to compare, and the drought rehydration was also studied. Results: the results indicated that H2O2 content, O2·-production rate, relative conductivity and MDA content were higher than the control, and the increase extent of Golden Empress was higher than the Sanditi under drought stress and after re-watering the recovery capability of Golden Empress was also higher than the Sanditi. After 7 days of re-watering, all indexes were restored to the control level, indicating that the re-watering have compensation effect after drought. After drought stress, to weaken the damage of active oxygen Golden Empress was mainly by increasing the activity of POD and SOD, but Sanditi was mainly through the POD and CAT activity increased to effectively remove ROS. Under drought stress, active oxygen in leaves of Alfalfa increased, and thus the membrane system was damaged which lead to the increase of MDA content and relative electric conductivity. Plants play a defensive role by increasing the activity of antioxidant enzymes and scavenging reactive oxygen species. After re-watering, the stress effect was reduced, and the physiological indexes of plants were restored to the control level. In general, tolerant cultivar has stronger antioxidant properties under drought and re-watering.

Cadmium and lead interactive effects on oxidative stress and antioxidative responses in rice seedlings.

Science.gov (United States)

Srivastava, Rajneesh Kumar; Pandey, Poonam; Rajpoot, Ritika; Rani, Anjana; Dubey, R S

2014-09-01

Interactive effects of two heavy metal pollutants Cd and Pb in the growth medium were examined on their uptake, production of reactive oxygen species (ROS), induction of oxidative stress and antioxidative defence responses in Indica rice (Oryza sativa L.) seedlings. When rice seedlings in sand culture were exposed to 150 μM Cd (NO3)2 or 600 μM Pb (CH3COO)2 individually or in combination for 8-16 days, a significant reduction in root/shoot length, fresh weight, relative water content, photosynthetic pigments and increased production of ROS (O2˙- and H2O2) was observed. Both Cd and Pb were readily taken up by rice roots and localisation of absorbed metals was greater in roots than in shoots. When present together in the growth medium, uptake of both the metals Cd and Pb declined by 25-40%. Scanning electron microscope (SEM) imaging of leaf stomata revealed that Pb caused more distortion in the shape of guard cells than Cd. Dithizone staining of roots showed localisation of absorbed Cd on root hairs and epidermal cells. Both Cd and Pb caused increased lipid peroxidation, protein carbonylation, decline in protein thiol and increase in non-protein thiol. The level of reduced forms of non-enzymic antioxidants glutathione (GSH) and ascorbate (AsA) and their redox ratios (GSH/AsA) declined, whereas the activities of antioxidative enzymes superoxide dismutase (SOD) and guaiacol peroxidase (GPX) increased in metal treated seedlings compared to controls. In-gel activity staining also revealed increased intensities of SOD and GPX isoforms with metal treatments. Catalase (CAT) activity increased during early days (8 days) of metal exposure and declined by 16 days. Results suggest that oxidative stress is an important component in expression of Cd and Pb toxicities in rice, though uptake of both metals gets reduced considerably when present together in the medium.

Effect of vitamin E and C supplementation on oxidative damage and total antioxidant capacity in lead-exposed workers.

Science.gov (United States)

Rendón-Ramírez, Adela-Leonor; Maldonado-Vega, María; Quintanar-Escorza, Martha-Angelica; Hernández, Gerardo; Arévalo-Rivas, Bertha-Isabel; Zentella-Dehesa, Alejandro; Calderón-Salinas, José-Víctor

2014-01-01

The molecular response of the antioxidant system and the effects of antioxidant supplementation against oxidative insult in lead-exposed workers has not been sufficiently studied. In this work, antioxidants (vitamin E 400 IU+vitamin C 1g/daily) were supplemented for one year to 15 workers exposed to lead (73 μg of lead/dl of blood) and the results were compared with those on 19 non-lead exposed workers (6.7 μg of lead/dl). Lead intoxication was accompanied by a high oxidative damage and an increment in the erythrocyte antioxidant response due to increased activity of catalase and superoxide dismutase. Antioxidant supplementations decreased significantly the oxidative damage as well as the total antioxidant capacity induced by lead intoxication with reduction of the antioxidant enzyme activities. We conclude that antioxidant supplementation is effective in reducing oxidative damage and induces modifications in the physiopathological status of the antioxidant response in lead-exposed workers. Copyright © 2013 Elsevier B.V. All rights reserved.

The dipteran parasitoid Exorista bombycis induces pro- and anti-oxidative reactions in the silkworm Bombyx mori: Enzymatic and genetic analysis.

Science.gov (United States)

Makwana, Pooja; Pradeep, Appukuttan Nair R; Hungund, Shambhavi P; Ponnuvel, Kangayam M; Trivedy, Kanika

2017-02-01

Hymenopteran parasitoids inject various factors including polydnaviruses along with their eggs into their host insects that suppress host immunity reactions to the eggs and larvae. Less is known about the mechanisms evolved in dipteran parasitoids that suppress host immunity. Here we report that the dipteran, Exorista bombycis, parasitization leads to pro-oxidative reactions and activation of anti-oxidative enzymes in the silkworm Bombyx mori larva. We recorded increased activity of oxidase, superoxide dismutase, thioredoxin peroxidase, catalase, glutathione-S-transferase (GST), and peroxidases in the hemolymph plasma, hemocytes, and fat body collected from B. mori after E. bombycis parasitization. Microarray and qPCR showed differential expression of genes encoding pro- and anti-oxidant enzymes in the hemocytes. The significance of this work lies in increased understanding of dipteran parasitoid biology. © 2017 Wiley Periodicals, Inc.

Haloperidol Suppresses NF-kappaB to Inhibit Lipopolysaccharide-Induced Pro-Inflammatory Response in RAW 264 Cells.

Science.gov (United States)

Yamamoto, Shunsuke; Ohta, Noriyuki; Matsumoto, Atsuhiro; Horiguchi, Yu; Koide, Moe; Fujino, Yuji

2016-02-04

BACKGROUND Haloperidol, a tranquilizing agent, is administered both to treat symptoms of psychotic disorders and to sedate agitated and delirious patients. Notably, haloperidol has been suggested to inhibit the immune response through unknown mechanisms. We hypothesized that the sedative modulates the immune response via NF-κB. MATERIAL AND METHODS Using flow cytometry, we analyzed the effects of haloperidol on expression CD80 and CD86 in RAW 264 cells and in primary macrophages derived from bone marrow. Secretion of interleukin (IL)-1β, IL-6, and IL-12 p40 was measured by enzyme-linked immunosorbent assay. In addition, NF-κB activation was evaluated using a reporter assay based on secretory embryonic alkaline phosphatase. Finally, synthetic antagonists were used to identify the dopamine receptor that mediates the effects of haloperidol. RESULTS Haloperidol inhibited NF-κB activation, and thereby suppressed expression of CD80, as well as secretion of IL-1β, IL-6, and IL-12 p40. CD80 and IL-6 levels were similarly attenuated by a D2-like receptor antagonist, but not by a D1-like receptor antagonist. CONCLUSIONS The data strongly suggest that haloperidol inhibits the immune response by suppressing NF-kB signaling via the dopamine D2 receptor.

Lettuce irrigated with contaminated water: Photosynthetic effects, antioxidative response and bioaccumulation of microcystin congeners.

Science.gov (United States)

Bittencourt-Oliveira, Maria do Carmo; Cordeiro-Araújo, Micheline Kézia; Chia, Mathias Ahii; Arruda-Neto, João Dias de Toledo; de Oliveira, Ênio Tiago; dos Santos, Flávio

2016-06-01

The use of microcystins (MCs) contaminated water to irrigate crop plants represents a human health risk due to their bioaccumulation potential. In addition, MCs cause oxidative stress and negatively influence photosynthetic activities in plants. The present study was aimed at investigating the effect of MCs on photosynthetic parameters and antioxidative response of lettuce. Furthermore, the bioaccumulation factor (BAF) of total MCs, MC-LR and MC-RR in the vegetable after irrigation with contaminated water was determined. Lettuce crops were irrigated for 15 days with water containing cyanobacterial crude extracts (Microcystis aeruginosa) with MC-LR (0.0, 0.5, 2.0, 5.0 and 10.0 µg L(-1)), MC-RR (0.0, 0.15, 0.5, 1.5 and 3.0 µg L(-1)) and total MCs (0.0, 0.65, 2.5, 6.5 and 13.0 µg L(-1)). Increased net photosynthetic rate, stomatal conductance, leaf tissue transpiration and intercellular CO2 concentration were recorded in lettuce exposed to different MCs concentrations. Antioxidant response showed that glutathione S-transferase activity was down-regulated in the presence of MCs. On the other hand, superoxide dismutase, catalase and peroxidase activities were upregulated with increasing MCs concentrations. The bioaccumulation factor (BAF) of total MCs and MC-LR was highest at 6.50 and 5.00 µg L(-1), respectively, while for MC-RR, the highest BAF was recorded at 1.50 µg L(-1) concentration. The amount of total MCs, MC-LR and MC-RR bioacumulated in lettuce was highest at the highest exposure concentrations. However, at the lowest exposure concentration, there were no detectable levels of MC-LR, MC-RR and total MCs in lettuce. Thus, the bioaccumulation of MCs in lettuce varies according to the exposure concentration. In addition, the extent of physiological response of lettuce to the toxins relies on exposure concentrations. Copyright © 2016 Elsevier Inc. All rights reserved.

Protein A Suppresses Immune Responses during Staphylococcus aureus Bloodstream Infection in Guinea Pigs

Science.gov (United States)

Kim, Hwan Keun; Falugi, Fabiana; Thomer, Lena; Missiakas, Dominique M.

2015-01-01

ABSTRACT   Staphylococcus aureus infection is not associated with the development of protective immunity, and disease relapses occur frequently. We hypothesize that protein A, a factor that binds immunoglobulin Fcγ and cross-links VH3 clan B cell receptors (IgM), is the staphylococcal determinant for host immune suppression. To test this, vertebrate IgM was examined for protein A cross-linking. High VH3 binding activity occurred with human and guinea immunoglobulin, whereas mouse and rabbit immunoglobulins displayed little and no binding, respectively. Establishing a guinea pig model of S. aureus bloodstream infection, we show that protein A functions as a virulence determinant and suppresses host B cell responses. Immunization with SpAKKAA, which cannot bind immunoglobulin, elicits neutralizing antibodies that enable guinea pigs to develop protective immunity. Importance  Staphylococcus aureus is the leading cause of soft tissue and bloodstream infections; however, a vaccine with clinical efficacy is not available. Using mice to model staphylococcal infection, earlier work identified protective antigens; however, corresponding human clinical trials did not reach their endpoints. We show that B cell receptor (IgM) cross-linking by protein A is an important immune evasion strategy of S. aureus that can be monitored in a guinea pig model of bloodstream infection. Further, immunization with nontoxigenic protein A enables infected guinea pigs to elicit antibody responses that are protective against S. aureus. Thus, the guinea pig model may support preclinical development of staphylococcal vaccines. PMID:25564466

Experimental studies on anti-oxidants reducing lipid peroxidation of irradiated mice

International Nuclear Information System (INIS)

Du Zeji; Liu Keliang; Su Liaoyuan

1993-08-01

The free radical plays an important role in the irradiation damage. The irradiation damage would be reduced if anti-oxidants is used, because anti-oxidants can scavenge free radicals and suppress lipid peroxidation. In the study, a fluoro-spectrophotometer was used to determine the changes of MDA levels in mice tissues and serum after irradiation and the protective effect of anti-oxidants of Vit E and DMSO on damage caused by free radicals. The results are as follows: (1) The highest MDA level was at 12 to 24 hours after irradiation dose of 3.0 Gy. (2) The MDA level is increasing with the increasing of irradiation dose. It means the MDA level can indicate the extent of irradiation damage. (3) Both Vit E and DMSO had a powerful effect on reducing MDA level, but the effect of DMSO was stronger than Vit E. The optimum doses of them were 0.25 mg/g body weight and 10 mg/g body weight respectively. (4) The best effect obtained was to use Vit E and DMSO simultaneously

Modulation of liver function, antioxidant responses, insulin resistance and glucose transport by Oroxylum indicum stem bark in STZ induced diabetic rats.

Science.gov (United States)

Singh, Jyotsna; Kakkar, Poonam

2013-12-01

A decoction of stem bark of Oroxylum indicum Vent. (OI) is taken (2-3 times/day) by the tribal people of Sikkim, India to treat diabetes but scientific validation of its overall potential is lacking. Present study was aimed to assess in vitro antihyperglycemic activity of standardized OI extract using inhibition of α-glucosidase, BSA glycation and enhancement of insulin sensitivity. Antidiabetic and antioxidant modulatory effects of OI extract along with the blood biomarkers of toxic response were studied in streptozotocin (STZ) induced diabetic rats. In vitro analysis showed strong antioxidant capacity of OI -and potential to inhibit BSA glycation and α-glucosidase activity which was comparable to standard counterparts. Extract also improved insulin sensitivity in mature 3T3-L1 adipocytes. In vivo effects of OI extract (oral 250 mg/kg b.wt.) on STZ induced type II diabetic rats normalized the antioxidant status (p≤0.01). Analysis of blood biomarkers of toxic response indicated its safety. Lowering of total cholesterol and HDL levels (p≤0.05) and restoration of glycated Hb (p≤0.01) were also found in OI treated diabetic rats. HOMA-IR, QUICKI analysis along with area under the curve analysis showed the capacity of OI extract to enhance the insulin sensitivity significantly (p≤0.01) which was confirmed by increased GLUT-4 translocation in skeletal muscles. Copyright © 2013 Elsevier Ltd. All rights reserved.

Castasterone confers copper stress tolerance by regulating antioxidant enzyme responses, antioxidants, and amino acid balance in B. juncea seedlings.

Science.gov (United States)

Yadav, Poonam; Kaur, Ravdeep; Kanwar, Mukesh Kumar; Sharma, Anket; Verma, Vinod; Sirhindi, Geetika; Bhardwaj, Renu

2018-01-01

The aim of the present study was to explore the effect of exogenous application of castasterone (CS) on physiologic and biochemical responses in Brassica juncea seedlings under copper (Cu) stress. Seeds were pre-soaked in different concentrations of CS and grown for 7 days under various levels of Cu. The exposure of B. juncea to higher levels of Cu led to decrease of morphologic parameters, with partial recovery of length and fresh weight in the CS pre-treated seedlings. Metal content was high in both roots and shoots under Cu exposure while the CS pre-treatment reduced the metal uptake. Accumulation of hydrogen peroxide (H 2 O 2 ) and superoxide anion radical (O 2 - ) were chosen as stress biomarker and higher levels of H 2 O 2 (88.89%) and O 2 - (62.11%) showed the oxidative stress in metal treated B. juncea seedlings, however, CS pre-treatment reduced ROS accumulation in Cu-exposed seedlings. The Cu exposures lead to enhance the plant's enzymatic and non-enzymatic antioxidant system. It was observed that enzymatic activities of ascorbate peroxidase (APOX), dehydroascorbate reductase (DHAR), and glutathione reductase (GR), glutathione perxoidase (GPOX) and gultrathione-s-transferase increased while activity of monodehydroascorbate reductase (MDHAR) decreased under Cu stress. The pre-treatment with CS positively affected the activities of enzymes. RT-PCR analysis showed that mRNA transcript levels were correlated with total enzymatic activity of DHAR, GR, GST and GSH. Increase in the gene expression of DHAR (1.85 folds), GR (3.24 folds), GST-1 (2.00 folds) and GSH-S (3.18 folds) was noticed with CS pre-treatment. Overall, the present study shows that Cu exposure induced severe oxidative stress in B. juncea plants and exogenous application of CS improved antioxidative defense system by modulating the ascorbate-glutathione cycle and amino acid metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

Suppression of the immune response to ovalbumin in vivo by anti-idiotypic antibodies

International Nuclear Information System (INIS)

Grinevich, A.S.; Pinegin, B.V.

1986-01-01

Conditions of suppression of the immune response to a food allergin (ovalbumin) were studied with the aid of anti-idiotypic (AID) antibodies. Hen ovalbumin was used and the experiments were performed on mice. Antibodies were isolated from the resulting protein fractions and tested for inhibitor activity by the method of direct radioimmunologic analysis. The test system consisted of the reaction of binding the globulin fraction to the total preparation of antibodies to ovalbumin from mice and a 125 I-labeled total preparation of antibodies to ovalbumin of the same animals

Induction of cell death by tospoviral protein NSs and the motif critical for cell death does not control RNA silencing suppression activity.

Science.gov (United States)

Singh, Ajeet; Permar, Vipin; Jain, R K; Goswami, Suneha; Kumar, Ranjeet Ranjan; Canto, Tomas; Palukaitis, Peter; Praveen, Shelly

2017-08-01

Groundnut bud necrosis virus induces necrotic symptoms in different hosts. Previous studies showed reactive oxygen species-mediated programmed cell death (PCD) resulted in necrotic symptoms. Transgenic expression of viral protein NSs mimics viral symptoms. Here, we showed a role for NSs in influencing oxidative burst in the cell, by analyzing H 2 O 2 accumulation, activities of antioxidant enzymes and expression levels of vacuolar processing enzymes, H 2 O 2 -responsive microRNA 319a.2 plus its possible target metacaspase-8. The role of NSs in PCD, was shown using two NSs mutants: one in the Trp/GH3 motif (a homologue of pro-apototic domain) (NSs S189R ) and the other in a non-Trp/GH3 motif (NSs L172R ). Tobacco rattle virus (TRV) expressing NSs S189R enhanced the PCD response, but not TRV-NSs L172R , while RNA silencing suppression activity was lost in TRV-NSs L172R , but not in TRV-NSs S189R . Therefore, we propose dual roles of NSs in RNA silencing suppression and induction of cell death, controlled by different motifs. Copyright © 2017 Elsevier Inc. All rights reserved.

Analysis of Globodera rostochiensis effectors reveals conserved functions of SPRYSEC proteins in suppressing and eliciting plant immune responses

KAUST Repository

Ali, Shawkat; Magne, Maxime; Chen, Shiyan; Obradovic, Natasa; Jamshaid, Lubna; Wang, Xiaohong; Bé lair, Guy; Moffett, Peter

2015-01-01

in Nicotiana benthamiana and N. tabacum. We have found that all SPRYSEC proteins tested are able to suppress defense responses induced by NB-LRR proteins as well as cell death induced by elicitors, suggesting that defense repression is a common characteristic

Ultrasound-Assisted Extraction of Total Flavonoids from Corn Silk and Their Antioxidant Activity

Directory of Open Access Journals (Sweden)

Ling-Li Zheng

2016-01-01

Full Text Available Object. Ultrasound-assisted extraction of total flavonoids from corn silk and their antioxidant activities were studied. Methods. Response surface methodology was adopted to optimize the extraction conditions and antioxidant activities of the extracted total flavonoids were detected through ferric reducing antioxidant power (FRAP assay. Results. Through a three-level, three-variable Box-Behnken design of response surface methodology (RSM adopting yield as response, the optimal conditions were determined as follows: ultrasonic power 500 W, extraction time 20 min, material solvent ratio 1 : 20, and ethanol concentration 30%. Under the optimum conditions, the extraction yield of total flavonoids was 1.13%. FRAP value of total flavonoids extracted from corn silk was 467.59 μmol/L. Conclusion. The total flavonoids of corn silk could be developed as food natural antioxidant reagents.

Ultrasonic Extraction of Antioxidants from Chinese Sumac (Rhus typhina L.) Fruit Using Response Surface Methodology and Their Characterization

OpenAIRE

Lai, Jixiang; Wang, Huifang; Wang, Donghui; Fang, Fang; Wang, Fengzhong; Wu, Tao

2014-01-01

For the first time, response surface methodology (RSM) using a Box-Behnken Design (BBD) was employed to optimize the conditions for ultrasonic assisted extraction (UAE) of antioxidants from Chinese sumac (Rhus typhina L.) fruits. Initially, influencing factors such as liquid-solid ratio, duration of ultrasonic assisted extraction, pH range, extraction temperature and ethanol concentration were identified using single-factor experiments. Then, with respect to the three most significant influen...

Silicon-enhanced resistance to cadmium toxicity in Brassica chinensis L. is attributed to Si-suppressed cadmium uptake and transport and Si-enhanced antioxidant defense capacity

Energy Technology Data Exchange (ETDEWEB)

Song Alin [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Li Zhaojun [Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Zhang Jie [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Xue Gaofeng; Fan Fenliang [Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Liang Yongchao, E-mail: ycliang@caas.ac.cn [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Key Laboratory of Oasis Eco-Agriculture, College of Agriculture, Shihezi University, Shihezi 832003 (China)

2009-12-15

A series of hydroponics experiments were performed to investigate roles of silicon (Si) in enhancing cadmium (Cd) tolerance in two pakchoi (Brassica chinensis L.) cultivars: i.e. cv. Shanghaiqing, a Cd-sensitive cultivar, and cv. Hangyoudong, a Cd-tolerant cultivar. Plants were grown under 0.5 and 5 mg Cd L{sup -1} Cd stress without or with 1.5 mM Si. Plant growth of the Cd-tolerant cultivar was stimulated at the lower Cd level, but was decreased at the higher Cd level when plants were treated with Cd for one week. However, Plant growth was severely inhibited at both Cd levels as stress duration lasted for up to three weeks. Plant growth of the Cd-sensitive cultivar was severely inhibited at both Cd levels irrespective of Cd stress duration. Addition of Si increased shoot and root biomass of both cultivars at both Cd levels and decreased Cd uptake and root-to-shoot transport. Superoxide dismutase, catalase and ascorbate peroxidase activities decreased, but malondialdehyde and H{sub 2}O{sub 2} concentrations increased at the higher Cd level, which were counteracted by Si added. Ascorbic acid, glutathione and non-protein thiols concentrations increased at the higher Cd level, which were further intensified by addition of Si. The effects of Si and Cd on the antioxidant enzyme activity were further verified by isoenzyme analysis. Silicon was more effective in enhancing Cd tolerance in the Cd-tolerant cultivar than in the Cd-sensitive cultivar. It can be concluded that Si-enhanced Cd tolerance in B. chinensis is attributed mainly to Si-suppressed Cd uptake and root-to-shoot Cd transport and Si-enhanced antioxidant defense activity.

Silicon-enhanced resistance to cadmium toxicity in Brassica chinensis L. is attributed to Si-suppressed cadmium uptake and transport and Si-enhanced antioxidant defense capacity

International Nuclear Information System (INIS)

Song Alin; Li Zhaojun; Zhang Jie; Xue Gaofeng; Fan Fenliang; Liang Yongchao

2009-01-01

A series of hydroponics experiments were performed to investigate roles of silicon (Si) in enhancing cadmium (Cd) tolerance in two pakchoi (Brassica chinensis L.) cultivars: i.e. cv. Shanghaiqing, a Cd-sensitive cultivar, and cv. Hangyoudong, a Cd-tolerant cultivar. Plants were grown under 0.5 and 5 mg Cd L -1 Cd stress without or with 1.5 mM Si. Plant growth of the Cd-tolerant cultivar was stimulated at the lower Cd level, but was decreased at the higher Cd level when plants were treated with Cd for one week. However, Plant growth was severely inhibited at both Cd levels as stress duration lasted for up to three weeks. Plant growth of the Cd-sensitive cultivar was severely inhibited at both Cd levels irrespective of Cd stress duration. Addition of Si increased shoot and root biomass of both cultivars at both Cd levels and decreased Cd uptake and root-to-shoot transport. Superoxide dismutase, catalase and ascorbate peroxidase activities decreased, but malondialdehyde and H 2 O 2 concentrations increased at the higher Cd level, which were counteracted by Si added. Ascorbic acid, glutathione and non-protein thiols concentrations increased at the higher Cd level, which were further intensified by addition of Si. The effects of Si and Cd on the antioxidant enzyme activity were further verified by isoenzyme analysis. Silicon was more effective in enhancing Cd tolerance in the Cd-tolerant cultivar than in the Cd-sensitive cultivar. It can be concluded that Si-enhanced Cd tolerance in B. chinensis is attributed mainly to Si-suppressed Cd uptake and root-to-shoot Cd transport and Si-enhanced antioxidant defense activity.

The effects of imipramine on P50 suppression, prepulse inhibition and habituation of the startle response in humans

DEFF Research Database (Denmark)

Hammer, Trine Bjørg; Oranje, Bob; Glenthoj, Birte Y

2007-01-01

Schizophrenic patients exhibit impairments in filtering of sensory information, as can be assessed by use of prepulse inhibition (PPI) of the acoustic startle response and P50 suppression paradigms. In the treatment of negative symptoms or depressive syndromes during the course of schizophrenia...... as well as P50 suppression. No significant differences between the two treatments were observed on habituation of the acoustic startle reflex. Since sensory filtering is usually already reduced in patients with schizophrenia, the current results call for caution in the widespread use of dual......-acting antidepressants in the treatment of depressed or negative symptoms in these patients....

Deer Bone Oil Extract Suppresses Lipopolysaccharide-Induced Inflammatory Responses in RAW264.7 Cells.

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Choi, Hyeon-Son; Im, Suji; Park, Yooheon; Hong, Ki-Bae; Suh, Hyung Joo

2016-01-01

The aim of this study was to investigate the effect of deer bone oil extract (DBOE) on lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells. DBOE was fractionated by liquid-liquid extraction to obtain two fractions: methanol fraction (DBO-M) and hexane fraction (DBO-H). TLC showed that DBO-M had relatively more hydrophilic lipid complexes, including unsaturated fatty acids, than DBOE and DBO-H. The relative compositions of tetradecenoyl carnitine, α-linoleic acid, and palmitoleic acid increased in the DBO-M fraction by 61, 38, and 32%, respectively, compared with DBOE. The concentration of sugar moieties was 3-fold higher in the DBO-M fraction than DBOE and DBO-H. DBO-M significantly decreased LPS-induced nitric oxide (NO) production in RAW264.7 cells in a dose-dependent manner. This DBO-M-mediated decrease in NO production was due to downregulation of mRNA and protein levels of inducible nitric oxide synthase (iNOS). In addition, mRNA expression of pro-inflammatory mediators, such as cyclooxygenase (COX-2), interleukin (IL)-1β, and IL-12β, was suppressed by DBO-M. Our data showed that DBO-M, which has relatively higher sugar content than DBOE and DBO-H, could play an important role in suppressing inflammatory responses by controlling pro-inflammatory cytokines and mediators.

Involvement of an antioxidant defense system in the adaptive response to cadmium in maize seedlings (Zea mays L.).

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Xu, Xianghua; Liu, Cuiying; Zhao, Xiaoyan; Li, Renying; Deng, Wenjing

2014-11-01

Chemical and biological analyses were used to investigate the growth response and antioxidant defense mechanism of maize seedlings (Zea mays L.) grown in soils with 0-100 mg kg(-1) Cd. Results showed that maize seedlings have strong abilities to accumulate and tolerate high concentrations of Cd. For soil with 50 mg kg(-1) Cd, the Cd contents in roots and shoots of maize seedlings are as large as 295.6 and 153.0 mg kg(-1) DW, respectively, without visible symptoms of toxicity. Lower soil Cd concentrations lead to a decrease in reduced glutathione (GSH) content in leaves of maize seedlings, whereas higher soil Cd concentrations resulted in an increase in the activities of superoxide dismutase, guaiacol peroxidase, catalase, and ascorbate peroxidase. Maize seedlings have strong capacities to adapt to low concentrations of Cd by consuming GSH and to develop an antioxidative enzyme system to defend against high-Cd stress.

Fisetin inhibits the generation of inflammatory mediators in interleukin-1β-induced human lung epithelial cells by suppressing the NF-κB and ERK1/2 pathways.

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Peng, Hui-Ling; Huang, Wen-Chung; Cheng, Shu-Chen; Liou, Chian-Jiun

2018-07-01

Fisetin, a flavone that can be isolated from fruits and vegetables, has anti-tumor and anti-oxidative properties and ameliorates airway hyperresponsiveness in asthmatic mice. This study investigated whether fisetin can suppress the expression of inflammatory mediators and intercellular adhesion molecule 1 (ICAM-1) in A549 human lung epithelial cells that were stimulated with interleukin-1β (IL-1β) to induce inflammatory responses. A549 cells were treated with fisetin (3-30 μM) and then with IL-1β. Fisetin significantly inhibited COX-2 expression and reduced prostaglandin E 2 production, and it suppressed the levels of IL-8, CCL5, monocyte chemotactic protein 1, tumor necrosis factor α, and IL-6. Fisetin also significantly attenuated the expression of chemokine and inflammatory cytokine genes and decreased the expression of ICAM-1, which mediates THP-1 monocyte adhesion to inflammatory A549 cells. Fisetin decreased the translocation of nuclear transcription factor kappa-B (NF-κB) subunit p65 into the nucleus and inhibited the phosphorylation of proteins in the ERK1/2 pathway. Co-treatment of IL-1β-stimulated A549 cells with ERK1/2 inhibitors plus fisetin reduced ICAM-1 expression. Furthermore, fisetin significantly increased the effects of the protective antioxidant pathway by promoting the expression of nuclear factor erythroid-2-related factor-2 and heme oxygenase 1. Taken together, these data suggest that fisetin has anti-inflammatory effects and that it suppresses the expression of chemokines, inflammatory cytokines, and ICAM-1 by suppressing the NF-κB and ERK1/2 signaling pathways in IL-1β-stimulated human lung epithelial A549 cells. Copyright © 2018 Elsevier B.V. All rights reserved.

Phytoextract of Indian mustard seeds acts by suppressing the generation of ROS against acetaminophen-induced hepatotoxicity in HepG2 cells.

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Parikh, Harita; Pandita, Nancy; Khanna, Aparna

2015-07-01

Indian mustard [Brassica juncea (L.) Czern. & Coss. (Brassicaceae)] is reported to possess diverse pharmacological properties. However, limited information is available concerning its hepatoprotective activity and mechanism of action. To study the protective mechanism of mustard seed extract against acetaminophen (APAP) toxicity in a hepatocellular carcinoma (HepG2) cell line. Hepatotoxicity models were established using APAP (2.5-22.5 mM) based on the cytotoxicity profile. An antioxidant-rich fraction from mustard seeds was extracted and evaluated for its hepatoprotective potential. The mechanism of action was elucidated using various in vitro antioxidant assays, the detection of intracellular generation of reactive oxygen species (ROS), and cell cycle analysis. The phytoconstituents isolated via HPLC-DAD were also evaluated for hepatoprotective activity. Hydromethanolic seed extract exhibited hepatoprotective activity in post- and pre-treatment models of 20 mM APAP toxicity and restored the elevated levels of liver indices to normal values (p DAD analysis revealed the presence quercetin, vitamin E, and catechin, which exhibited hepatoprotective activity. A phytoextract of mustard seeds acts by suppressing the generation of ROS in response to APAP toxicity.

Hydroxysafflor yellow A suppress oleic acid-induced acute lung injury via protein kinase A

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Wang, Chaoyun; Huang, Qingxian; Wang, Chunhua; Zhu, Xiaoxi; Duan, Yunfeng; Yuan, Shuai; Bai, Xianyong

2013-01-01

Inflammation response and oxidative stress play important roles in acute lung injury (ALI). Activation of the cAMP/protein kinase A (PKA) signaling pathway may attenuate ALI by suppressing immune responses and inhibiting the generation of reactive oxygen species (ROS). Hydroxysafflor yellow A (HSYA) is a natural flavonoid compound that reduces oxidative stress and inflammatory cytokine-mediated damage. In this study, we examined whether HSYA could protect the lungs from oleic acid (OA)-induced injury, which was used to mimic ALI, and determined the role of the cAMP/PKA signaling pathway in this process. Arterial oxygen tension (PaO 2 ), carbon dioxide tension, pH, and the PaO 2 /fraction of inspired oxygen ratio in the blood were detected using a blood gas analyzer. We measured wet/dry lung weight ratio and evaluated tissue morphology. The protein and inflammatory cytokine levels in the bronchoalveolar lavage fluid and serum were determined using enzyme-linked immunoassay. The activities of superoxide dismutase, glutathione peroxidase, PKA, and nicotinamide adenine dinucleotide phosphate oxidase, and the concentrations of cAMP and malondialdehyde in the lung tissue were detected using assay kits. Bcl-2, Bax, caspase 3, and p22 phox levels in the lung tissue were analyzed using Western blotting. OA increased the inflammatory cytokine and ROS levels and caused lung dysfunction by decreasing cAMP synthesis, inhibiting PKA activity, stimulating caspase 3, and reducing the Bcl-2/Bax ratio. H-89 increased these effects. HSYA significantly increased the activities of antioxidant enzymes, inhibited the inflammatory response via cAMP/PKA pathway activation, and attenuated OA-induced lung injury. Our results show that the cAMP/PKA signaling pathway is required for the protective effect of HSYA against ALI. - Highlights: • Oleic acid (OA) cause acute lung injury (ALI) via inhibiting cAMP/PKA signal pathway. • Blocking protein kinase A (PKA) activation may enhance Cytokine

Quercetin Suppresses Twist to Induce Apoptosis in MCF-7 Breast Cancer Cells.

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Santhalakshmi Ranganathan

Full Text Available Quercetin is a dietary flavonoid which exerts anti-oxidant, anti-inflammatory and anti-cancer properties. In this study, we investigated the anti-proliferative effect of quercetin in two breast cancer cell lines (MCF-7 and MDA-MB-231, which differed in hormone receptor. IC50 value (37μM of quercetin showed significant cytotoxicity in MCF-7 cells, which was not observed in MDA-MB-231 cells even at 100μM of quercetin treatment. To study the response of cancer cells to quercetin, with respect to different hormone receptors, both the cell lines were treated with a fixed concentration (40μM of quercetin. MCF-7 cells on quercetin treatment showed more apoptotic cells with G1 phase arrest. In addition, quercetin effectively suppressed the expression of CyclinD1, p21, Twist and phospho p38MAPK, which was not observed in MDA-MB-231 cells. To analyse the molecular mechanism of quercetin in exerting an apoptotic effect in MCF-7 cells, Twist was over-expressed and the molecular changes were observed after quercetin administration. Quercetin effectively regulated the expression of Twist, in turn p16 and p21 which induced apoptosis in MCF-7 cells. In conclusion, quercetin induces apoptosis in breast cancer cells through suppression of Twist via p38MAPK pathway.

Macrophage antioxidant protection within atherosclerotic plaques.

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Gieseg, Steven P; Leake, David S; Flavall, Elizabeth M; Amit, Zunika; Reid, Linzi; Yang, Ya-Ting

2009-01-01

Macrophage cells within inflammatory lesions are exposed to a wide range of degrading and cytotoxic molecules including reactive oxygen species. Unlike neutrophils, macrophages do not normally die in this environment but continue to generate oxidants, phagocytose cellular remains, and release a range of cyto-active agents which modulate the immune response. It is this potential of the macrophage cell to survive in an oxidative environment that allows the growth and complexity of advanced atherosclerotic plaques. This review will examine the oxidants encountered by macrophages within an atherosclerotic plaque and describe some of the potential antioxidant mechanisms which enable macrophages to function within inflammatory lesions. Ascorbate, a-tocopherol, and glutathione appear to be central to the protection of macrophages yet additional antioxidant mechanisms appear to be involved. Gamma-Interferon causes macrophages to generate 7,8-dihydroneopterin, neopterin and 3-hydroxyanthranilic acid both of which have antioxidant properties. Manganese superoxide dismutase is also upregulated in macrophages. The evidence that these antioxidants provide further protection, so allowing the macrophage cells to survive within sites of chronic inflammation such as atherosclerotic plaques, will be described.

Antioxidant Capacity and Antimutagenic Potential of Murraya koenigii

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Maryam Zahin

2013-01-01

Full Text Available It is well known that the intake of antioxidants with increased consumption of fruits and vegetables and medicinal herbs contributes towards reduced risk of certain diseases including cancers. This study aims to evaluate the broad-spectrum antioxidant and antimutagenic activities as well as to elucidate phytochemical profile of an Indian medicinal plant Murraya koenigii (curry leaves. Leaves of the plant were successively fractionated in various organic solvents. Benzene fraction demonstrated the highest phenolic content followed by petroleum ether. The benzene fraction showed maximum antioxidant activity in all tested assays, namely, phosphomolybdenum, 2,2-diphenyl-1-picrylhydrazyl (DPPH free radical, ferric reducing antioxidant power (FRAP and cupric reducing antioxidant capacity (CUPRAC assays. Based on the promising broad-spectrum antioxidant activity, benzene fraction was further evaluated for antimutagenic activity and showed a dose-dependent antimutagenic response in Ames Salmonella mutagenicity assay. It inhibited 72–86% mutagenicity induced by sodium azide, methyl methanesulfonate, benzo(apyrene, and 2-aminoflourene at the maximum tested concentration (100 μg/mL in Salmonella typhimurium tester strains. At least 21 compounds were detected by GC/MS. The findings clearly demonstrated that phenolic-rich benzene fraction has promising broad-spectrum antioxidant and antimutagenic property and needs further evaluation to exploit its therapeutic potential.

Solid-state studies and antioxidant properties of the γ-cyclodextrin·fisetin inclusion compound.

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Pais, Joana M; Barroca, Maria João; Marques, Maria Paula M; Almeida Paz, Filipe A; Braga, Susana S

2017-01-01

Fisetin is a natural antioxidant with a wide range of nutraceutical properties, including antidiabetic, neuroprotecting, and suppression or prevention of tumors. The present work describes the preparation of a water-soluble, solid inclusion compound of fisetin with gamma-cyclodextrin (γ-CD), a cyclic oligosaccharide approved for human consumption. A detailed physicochemical analysis of the product is carried out using elemental analysis, powder X-ray diffraction (PXRD), Raman, infrared and 13 C{ 1 H} CP-MAS NMR spectroscopies, and thermal analysis (TGA) to verify fisetin inclusion and to present a hypothetical structural arrangement for the host-guest units. The antioxidant activity of the γ-CD·fisetin inclusion compound is evaluated by the DPPH assay.

Solid-state studies and antioxidant properties of the γ-cyclodextrin·fisetin inclusion compound

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Joana M. Pais

2017-10-01

Full Text Available Fisetin is a natural antioxidant with a wide range of nutraceutical properties, including antidiabetic, neuroprotecting, and suppression or prevention of tumors. The present work describes the preparation of a water-soluble, solid inclusion compound of fisetin with gamma-cyclodextrin (γ-CD, a cyclic oligosaccharide approved for human consumption. A detailed physicochemical analysis of the product is carried out using elemental analysis, powder X-ray diffraction (PXRD, Raman, infrared and 13C{1H} CP-MAS NMR spectroscopies, and thermal analysis (TGA to verify fisetin inclusion and to present a hypothetical structural arrangement for the host–guest units. The antioxidant activity of the γ-CD·fisetin inclusion compound is evaluated by the DPPH assay.

Heterogeneous role of the glutathione antioxidant system in modulating the response of ESFT to fenretinide in normoxia and hypoxia.

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Tapiwanashe Magwere

Full Text Available Glutathione (GSH is implicated in drug resistance mechanisms of several cancers and is a key regulator of cell death pathways within cells. We studied Ewing's sarcoma family of tumours (ESFT cell lines and three mechanistically distinct anticancer agents (fenretinide, doxorubicin, and vincristine to investigate whether the GSH antioxidant system is involved in the reduced sensitivity to these chemotherapeutic agents in hypoxia. Cell viability and death were assessed by the trypan blue exclusion assay and annexin V-PI staining, respectively. Hypoxia significantly decreased the sensitivity of all ESFT cell lines to fenretinide-induced death, whereas the effect of doxorubicin or vincristine was marginal and cell-line-specific. The response of the GSH antioxidant system in ESFT cell lines to hypoxia was variable and also cell-line-specific, although the level of GSH appeared to be most dependent on de novo biosynthesis rather than recycling. RNAi-mediated knockdown of key GSH regulatory enzymes γ-glutamylcysteine synthetase or glutathione disulfide reductase partially reversed the hypoxia-induced resistance to fenretinide, and increasing GSH levels using N-acetylcysteine augmented the hypoxia-induced resistance in a cell line-specific manner. These observations are consistent with the conclusion that the role of the GSH antioxidant system in modulating the sensitivity of ESFT cells to fenretinide is heterogeneous depending on environment and cell type. This is likely to limit the value of targeting GSH as a therapeutic strategy to overcome hypoxia-induced drug resistance in ESFT. Whether targeting the GSH antioxidant system in conjunction with other therapeutics may benefit some patients with ESFT remains to be seen.

Reducing confounding and suppression effects in TCGA data: an integrated analysis of chemotherapy response in ovarian cancer

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Hsu Fang-Han

2012-10-01

Full Text Available Abstract Background Despite initial response in adjuvant chemotherapy, ovarian cancer patients treated with the combination of paclitaxel and carboplatin frequently suffer from recurrence after few cycles of treatment, and the underlying mechanisms causing the chemoresistance remain unclear. Recently, The Cancer Genome Atlas (TCGA research network concluded an ovarian cancer study and released the dataset to the public. The TCGA dataset possesses large sample size, comprehensive molecular profiles, and clinical outcome information; however, because of the unknown molecular subtypes in ovarian cancer and the great diversity of adjuvant treatments TCGA patients went through, studying chemotherapeutic response using the TCGA data is difficult. Additionally, factors such as sample batches, patient ages, and tumor stages further confound or suppress the identification of relevant genes, and thus the biological functions and disease mechanisms. Results To address these issues, herein we propose an analysis procedure designed to reduce suppression effect by focusing on a specific chemotherapeutic treatment, and to remove confounding effects such as batch effect, patient's age, and tumor stages. The proposed procedure starts with a batch effect adjustment, followed by a rigorous sample selection process. Then, the gene expression, copy number, and methylation profiles from the TCGA ovarian cancer dataset are analyzed using a semi-supervised clustering method combined with a novel scoring function. As a result, two molecular classifications, one with poor copy number profiles and one with poor methylation profiles, enriched with unfavorable scores are identified. Compared with the samples enriched with favorable scores, these two classifications exhibit poor progression-free survival (PFS and might be associated with poor chemotherapy response specifically to the combination of paclitaxel and carboplatin. Significant genes and biological processes are

Culturing on decellularized extracellular matrix enhances antioxidant properties of human umbilical cord-derived mesenchymal stem cells

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Liu, Xiaozhen; Zhou, Long; Chen, Xi; Liu, Tao; Pan, Guoqing; Cui, Wenguo; Li, Mao; Luo, Zong-Ping; Pei, Ming; Yang, Huilin; Gong, Yihong; He, Fan

2016-01-01

Human umbilical cord-derived mesenchymal stem cells (UC-MSCs) have attracted great interest in clinical application because of their regenerative potential and their lack of ethical issues. Our previous studies showed that decellularized cell-deposited extracellular matrix (ECM) provided an in vivo-mimicking microenvironment for MSCs and facilitated in vitro cell expansion. This study was conducted to analyze the cellular response of UC-MSCs when culturing on the ECM, including reactive oxygen species (ROS), intracellular antioxidative enzymes, and the resistance to exogenous oxidative stress. After decellularization, the architecture of cell-deposited ECM was characterized as nanofibrous, collagen fibrils and the matrix components were identified as type I and III collagens, fibronectin, and laminin. Compared to tissue culture polystyrene (TCPS) plates, culturing on ECM yielded a 2-fold increase of UC-MSC proliferation and improved the percentage of cells in the S phase by 2.4-fold. The levels of intracellular ROS and hydrogen peroxide (H_2O_2) in ECM-cultured cells were reduced by 41.7% and 82.9%, respectively. More importantly, ECM-cultured UC-MSCs showed enhanced expression and activity of intracellular antioxidative enzymes such as superoxide dismutase and catalase, up-regulated expression of silent information regulator type 1, and suppressed phosphorylation of p38 mitogen-activated protein kinase. Furthermore, a continuous treatment with exogenous 100 μM H_2O_2 dramatically inhibited osteogenic differentiation of UC-MSCs cultured on TCPS, but culturing on ECM retained the differentiation capacity for matrix mineralization and osteoblast-specific marker gene expression. Collectively, by providing sufficient cell amounts and enhancing antioxidant capacity, decellularized ECM can be a promising cell culture platform for in vitro expansion of UC-MSCs. - Highlights: • Decellularization preserved the architecture and components of cell-deposited ECM. �

Culturing on decellularized extracellular matrix enhances antioxidant properties of human umbilical cord-derived mesenchymal stem cells

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Liu, Xiaozhen [School of Engineering, Sun Yat-sen University, Guangzhou 510006 (China); Zhou, Long; Chen, Xi [Orthopaedic Institute, Soochow University, Suzhou 215007 (China); Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Liu, Tao [Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Pan, Guoqing; Cui, Wenguo; Li, Mao; Luo, Zong-Ping [Orthopaedic Institute, Soochow University, Suzhou 215007 (China); Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Pei, Ming [Stem Cell and Tissue Engineering Laboratory, Department of Orthopaedics, West Virginia University, Morgantown, WV 26506 (United States); Yang, Huilin [Orthopaedic Institute, Soochow University, Suzhou 215007 (China); Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Gong, Yihong, E-mail: gongyih@mail.sysu.edu.cn [School of Engineering, Sun Yat-sen University, Guangzhou 510006 (China); He, Fan, E-mail: fanhe@suda.edu.cn [Orthopaedic Institute, Soochow University, Suzhou 215007 (China); Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China)

2016-04-01

Human umbilical cord-derived mesenchymal stem cells (UC-MSCs) have attracted great interest in clinical application because of their regenerative potential and their lack of ethical issues. Our previous studies showed that decellularized cell-deposited extracellular matrix (ECM) provided an in vivo-mimicking microenvironment for MSCs and facilitated in vitro cell expansion. This study was conducted to analyze the cellular response of UC-MSCs when culturing on the ECM, including reactive oxygen species (ROS), intracellular antioxidative enzymes, and the resistance to exogenous oxidative stress. After decellularization, the architecture of cell-deposited ECM was characterized as nanofibrous, collagen fibrils and the matrix components were identified as type I and III collagens, fibronectin, and laminin. Compared to tissue culture polystyrene (TCPS) plates, culturing on ECM yielded a 2-fold increase of UC-MSC proliferation and improved the percentage of cells in the S phase by 2.4-fold. The levels of intracellular ROS and hydrogen peroxide (H{sub 2}O{sub 2}) in ECM-cultured cells were reduced by 41.7% and 82.9%, respectively. More importantly, ECM-cultured UC-MSCs showed enhanced expression and activity of intracellular antioxidative enzymes such as superoxide dismutase and catalase, up-regulated expression of silent information regulator type 1, and suppressed phosphorylation of p38 mitogen-activated protein kinase. Furthermore, a continuous treatment with exogenous 100 μM H{sub 2}O{sub 2} dramatically inhibited osteogenic differentiation of UC-MSCs cultured on TCPS, but culturing on ECM retained the differentiation capacity for matrix mineralization and osteoblast-specific marker gene expression. Collectively, by providing sufficient cell amounts and enhancing antioxidant capacity, decellularized ECM can be a promising cell culture platform for in vitro expansion of UC-MSCs. - Highlights: • Decellularization preserved the architecture and components of cell

Luminol-based electrochemiluminescent biosensors for highly sensitive medical diagnosis and rapid antioxidant detection

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Tamiya, Eiichi; Inoue, Yuki; Saito, Masato

2018-03-01

We present a review of luminol-based electrochemiluminescence (ECL) biosensors that perform enzymatic reactions and bioanalysis using antioxidant molecules by controlling the spatiotemporal production of a luminescent substrate, catalase activity, and glycated albumin (GA). The ECL intensity depends on the antioxidant capacity because radicals are neutralized by the antioxidants, which suppresses the luminescence. The antioxidant capacities of 22 types beverages were evaluated by comparison with a standard curve of Trolox. The time necessary for the ECL measurement of the antioxidant capacity is only 2 min with screen-printed electrodes and a portable ECL measurement system. Our system was also used to monitor reactive oxygen species released from neutrophils, which play an important role in the immune system, defending against viral and bacterial infections. The quenching of ECL imaging by catalase reaction localized in the multichamber electrode using the electrogenerated substrate was examined as a potential candidate for a sensitive reporting system. The substrate was successfully generated at applied potentials between -1 and -0.4 V in multichamber electrodes and the substrate confinement within the chamber was observed within 60 s of generation. The microchamber electrode system demonstrated a detection limit of 90 fM catalase. We also demonstrated a detection limit of 0.1 µM GA in human serum albumin, which is an improvement of about 70 times over colorimetric methods.

Radiation Therapy Induces Macrophages to Suppress Immune Responses Against Pancreatic Tumors in Mice

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Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Ly, Nancy Ngoc Giao; Nguy, Susanna; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Daley, Donnele; Barilla, Rocky; Tippens, Daniel; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu R.; Hajdu, Cristina; Pellicciotta, Ilenia; Oh, Philmo; Du, Kevin; Miller, George

2016-01-01

Background & Aims The role of radiation therapy in the treatment of patients with pancreatic ductal adenocarcinoma (PDA) is controversial. Randomized controlled trials investigating the efficacy of radiation therapy in patients with locally advanced unresectable PDA have reported mixed results, with effects ranging from modest benefit to worse outcome, compared with control therapies. We investigated whether radiation causes inflammatory cells to acquire an immune-suppressive phenotype that limits the therapeutic effects of radiation on invasive PDAs and accelerates progression of pre-invasive foci. Methods We investigated the effects of radiation in p48Cre;LSL-KrasG12D (KC) and p48Cre;LSLKrasG12D;LSL-Trp53R172H (KPC) mice, as well as in C57BL/6 mice with orthotopic tumors grown from FC1242 cells derived from KPC mice. Some mice were given neutralizing antibodies against macrophage colony stimulating factor 1 (CSF1 or MCSF) or F4/80. Pancreata were exposed to doses of radiation ranging from 2–12 Gy and analyzed by flow cytometry. Results Pancreata of KC mice exposed to radiation had a higher frequency of advanced pancreatic intraepithelial lesions and more foci of invasive cancer than pancreata of unexposed mice (controls); radiation reduced survival time by more than 6 months. A greater proportion of macrophages from invasive and pre-invasive pancreatic tumors had an immune-suppressive, M2-like phenotype, compared with control mice. Pancreata from mice exposed to radiation had fewer CD8+ T cells than controls and greater numbers of CD4+ T cells of T-helper 2 and T-regulatory cell phenotypes. Adoptive transfer of T cells from irradiated PDA to tumors of control mice accelerated tumor growth. Radiation induced production of MCSF by PDA cells. An antibody against MCSF prevented radiation from altering the phenotype of macrophages in tumors, increasing the anti-tumor T-cell response and slowing tumor growth. Conclusions Radiation exposure causes macrophages in PDAs

Clinical Effects of a Dietary Antioxidant Silicate Supplement, Microhydrin((R)), on Cardiovascular Responses to Exercise.

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Purdy Lloyd, Kimberly L.; Wasmund, Wendy; Smith, Leonard; Raven, Peter B.

2001-01-01

Amorphous silicate minerals, often described as rock flour, were once common in natural water sources and abundant in glacial stream waters. Not only do the silica mineral particles bond water and other elements for transport; they also can be adsorbed with reduced hydrogen, which releases electrons, providing antioxidant or reducing potential to surrounding fluids. The purpose of this investigation was to examine the cardiovascular responses during exercise after consumption of a dietary silicate mineral antioxidant supplement, Microhydrin((R)) (Royal BodyCare, Inc., Irving, TX). A clinical trial incorporating a double-blind, placebo-controlled, crossover experimental design was employed. Subjects received either active agent or placebo, four capsules per day, for 7 days before the trial. The trial evaluated six exercise bicycle-trained subjects performing a 40-km bicycling time trial. Ratings of perceived exertion and measurements of oxygen uptake, heart rate, performance workload, and preexercise and postexercise blood lactate concentrations were obtained. Although there were no differences (P >/=.05) in work performed, heart rate, oxygen uptake, and ratings of perceived exertion during the time trial, the postexercise blood lactate concentrations were significantly lower (P

Antioxidant effect of green tea on polymer gel dosimeter

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Samuel, E J J; Sathiyaraj, P; Deena, T; Kumar, D S

2015-01-01

Extract from Green Tea (GTE) acts as an antioxidant in acrylamide based polymer gel dosimeter. In this work, PAGAT gel was used for investigation of antioxidant effect of GTE.PAGAT was called PAGTEG (Polyacrylamide green tea extract gel dosimeter) after adding GTE. Free radicals in water cause pre polymerization of polymer gel before irradiation. Polyphenols from GTE are highly effective to absorb the free radicals in water. THPC is used as an antioxidant in polymer gel dosimeter but here we were replaced it by GTE and investigated its effect by spectrophotometer. GTE added PAGAT samples response was lower compared to THPC added sample. To increase the sensitivity of the PAGTEG, sugar was added. This study confirmed that THPC was a good antioxidant for polymer gel dosimeter. However, GTE also can be used as an antioxidant in polymer gel if use less quantity (GTE) and add sugar as sensitivity enhancer

Cellular Homeostasis and Antioxidant Response in Epithelial HT29 Cells on Titania Nanotube Arrays Surface

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Rabiatul Basria SMN Mydin

2017-01-01

Full Text Available Cell growth and proliferative activities on titania nanotube arrays (TNA have raised alerts on genotoxicity risk. Present toxicogenomic approach focused on epithelial HT29 cells with TNA surface. Fledgling cell-TNA interaction has triggered G0/G1 cell cycle arrests and initiates DNA damage surveillance checkpoint, which possibly indicated the cellular stress stimuli. A profound gene regulation was observed to be involved in cellular growth and survival signals such as p53 and AKT expressions. Interestingly, the activation of redox regulator pathways (antioxidant defense was observed through the cascade interactions of GADD45, MYC, CHECK1, and ATR genes. These mechanisms furnish to protect DNA during cellular division from an oxidative challenge, set in motion with XRRC5 and RAD50 genes for DNA damage and repair activities. The cell fate decision on TNA-nanoenvironment has been reported to possibly regulate proliferative activities via expression of p27 and BCL2 tumor suppressor proteins, cogent with SKP2 and BCL2 oncogenic proteins suppression. Findings suggested that epithelial HT29 cells on the surface of TNA may have a positive regulation via cell-homeostasis mechanisms: a careful circadian orchestration between cell proliferation, survival, and death. This nanomolecular knowledge could be beneficial for advanced medical applications such as in nanomedicine and nanotherapeutics.

Tannins and extracts of fruit byproducts: antibacterial activity against foodborne bacteria and antioxidant capacity.

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Widsten, Petri; Cruz, Cristina D; Fletcher, Graham C; Pajak, Marta A; McGhie, Tony K

2014-11-19

The shelf life of fresh fish and meat transported over long distances could be extended by using plant-based extracts to control spoilage bacteria. The goals of the present study were to identify plant-based extracts that effectively suppress the main spoilage bacteria of chilled fish and lamb and to assess their antioxidant capacity. The phenolic compounds in wood-based tannins and extracts isolated from byproducts of the fruit processing industry were identified and/or quantified. The total phenol content, but not the flavonoid to total phenol ratio, was strongly associated with higher antibacterial activity against several fish and lamb spoilage bacteria in zone of inhibition and minimum inhibitory concentration assays as well as greater antioxidant capacity in the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical assay. The most promising compounds in both cases, and thus good candidates for antibacterial packaging or antioxidant dietary supplements, were mango seed extract and tannic acid containing mostly polygalloyl glucose type phenols.

PPARα ligands activate antioxidant enzymes and suppress hepatic fibrosis in rats

International Nuclear Information System (INIS)

Toyama, Tetsuya; Nakamura, Hideki; Harano, Yuichi; Yamauchi, Norihito; Morita, Atsuhiro; Kirishima, Toshihiko; Minami, Masahito; Itoh, Yoshito; Okanoue, Takeshi

2004-01-01

Oxidative stress is a major pathogenetic factor in hepatic fibrosis. Peroxisome proliferator-activated receptor α (PPARα) is a nuclear receptor which is known to affect oxidative stress and PPARα ligands may have rescue effects on hepatic fibrosis. We tested this hypothesis using rat thioacetamide (TAA) models of liver cirrhosis. Rats were given intraperitoneal injection of TAA and treated with a diet containing one of the two PPARα ligands, Wy-14,643 (WY) or fenofibrate. WY treatment dramatically reduced hepatic fibrosis and also prevented the inhibition catalase of mRNA expression caused by TAA. Correspondingly, catalase activity increased in the TAA + WY group but decreased in the control TAA group. The antifibrotic action of fenofibrate in the TAA model was comparable with that of WY. PPARα ligands have an antifibrotic action in the rat TAA model of liver cirrhosis, probably due to an antioxidant effect of enhanced catalase expression and activity in the liver

The antioxidant activity of kombucha fermented milk products with stinging nettle and winter savory

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Vitas Jasmina S.

2013-01-01

Full Text Available This paper investigates the antioxidant activity of fermented milk products obtained by kombucha fermentation. Two starter cultures were used as follows: starter obtained after kombucha fermentation on sweetened stinging nettle extract; as well as starter obtained after kombucha fermentation on sweetened winter savory extract. The starters were added to milk with 0.8, 1.6 and 2.8% milk fat. Fermentation was carried out at 37, 40 and 43oC and stopped when the pH reached 4.5. Antioxidant activity to hydroxyl and DPPH radicals was monitored using response surface methodology. Kombucha fermented milk products with stinging nettle (KSN and with winter savory (KWS showed the same antioxidant response to hydroxyl and different response to DPPH radicals. Synergetic effect of milk fat and fermentation temperature to antioxidant activity to hydroxyl radicals for both types of kombucha fermented milk products (KSN and KWS was established. Optimum processing conditions in term of antioxidant activity are: milk fat around 2.8% and process temperature around 41 and 43°C for KSN and KWS respectively.

Electrochemical behaviour of polyphenol rich fruit juices using disposable screen-printed carbon electrodes: towards a rapid sensor for antioxidant capacity and individual antioxidants.

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Bordonaba, Jordi Giné; Terry, Leon A

2012-02-15

The analysis of antioxidants in different foodstuffs and especially fruits has become an active area of research which has lead to numerous antioxidant-assays being recently developed. Many antioxidants exhibit inherent electroactivity, and hence employing electrochemical methods could be a viable approach for evaluating the overall antioxidant capacity of a fresh produce matrix without the need for added reactive species. This work shows the possibility of using square wave voltammetry (SWV) and other electrochemical methods with disposable screen-printed carbon electrodes, to quantify and assess antioxidant activity and abundance of specific antioxidants, mainly polyphenols in selected soft fruit juices. Freshly squeezed black currant and strawberry juices of different cultivars and maturity stages were chosen according to known differences in their antioxidant profile. As a result of the increasing applied potential (0-1000 mV vs. Ag/AgCl) the electroactive compounds present in the juices were oxidised leading to a characteristic voltammetric profile for each of the samples analysed. Generally, black currant juices had greater oxidation peaks at lower potentials (<400 mV) which were indicators of higher antioxidant capacities. The relationship between sensor cumulative responses at different applied potentials and total or individual antioxidants, as determined by conventional spectrophotometric methods (FRAP, Folin-Ciocalteu) and HPLC (individual anthocyanins and ascorbate), respectively, are discussed in the context of the development of a rapid sensor for antioxidants. Copyright © 2011 Elsevier B.V. All rights reserved.

The Effect of Isomaltulose Together with Green Tea on Glycemic Response and Antioxidant Capacity: A Single-Blind, Crossover Study in Healthy Subjects.

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Suraphad, Passakorn; Suklaew, Phim On; Ngamukote, Sathaporn; Adisakwattana, Sirichai; Mäkynen, Kittana

2017-05-06

Isomaltulose, a naturally-occurring isomer of sucrose, is commonly used as an alternative sweetener in foods and beverages. The goal of this study was to determine the effect of isomaltulose together with green tea on postprandial plasma glucose and insulin concentration, as well as antioxidant capacity in healthy subjects. In a randomized, single-blind, crossover study, 15 healthy subjects (eight women and seven men; ages 23.5 ± 0.7 years; with body mass index of 22.6 ± 0.4 kg/m²) consumed five beverages: (1) 50 g sucrose in 400 mL water; (2) 50 g isomaltulose in 400 mL of water; (3) 400 mL of green tea; (4) 50 g sucrose in 400 mL of green tea; and (5) 50 g isomaltulose in 400 mL of green tea. Incremental area under postprandial plasma glucose, insulin, ferric reducing ability of plasma (FRAP) and malondialdehyde (MDA) concentration were determined during 120 min of administration. Following the consumption of isomaltulose, the incremental 2-h area under the curve (AUC 0-2 h ) indicated a higher reduction of postprandial glucose (43.4%) and insulin concentration (42.0%) than the consumption of sucrose. The addition of green tea to isomaltulose produced a greater suppression of postprandial plasma glucose (20.9%) and insulin concentration (37.7%). In accordance with antioxidant capacity, consumption of sucrose (40.0%) and isomaltulose (28.7%) caused the reduction of green tea-induced postprandial increases in FRAP. A reduction in postprandial MDA after drinking green tea was attenuated when consumed with sucrose (34.7%) and isomaltulose (17.2%). In conclusion, green tea could enhance the reduction of postprandial glucose and insulin concentration when consumed with isomaltulose. In comparison with sucrose, isomaltulose demonstrated less alteration of plasma antioxidant capacity after being consumed with green tea.

Suppressiveness of 18 composts against 7 pathosystems: Variability in pathogen response

NARCIS (Netherlands)

Termorshuizen, A.J.; Rijn, van E.; Gaag, van der D.J.; Alabouvette, C.; Chen, Y.; Lagerlöf, J.; Malandrakis, A.A.; Paplomatas, E.J.; Rämert, B.; Ryckeboer, J.; Steinberg, C.; Zmora-Nahum, S.

2006-01-01

Compost is often reported as a substrate that is able to suppress soilborne plant pathogens, but suppression varies according to the type of compost and pathosystem. Reports often deal with a single pathogen while in reality crops are attacked by multiple plant pathogens. The goal of the present

Tofacitinib Suppresses Antibody Responses to Protein Therapeutics in Murine Hosts1

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Onda, Masanori; Ghoreschi, Kamran; Steward-Tharp, Scott; Thomas, Craig; O’Shea, John J.; Pastan, Ira H.; FitzGerald, David J.

2014-01-01

Immunogenicity remains the ‘Achilles’ heel’ of protein-based therapeutics. Anti-drug antibodies produced in response to protein therapeutics can severely limit both the safety and efficacy of this expanding class of agent. Here we report that monotherapy of mice with tofacitinib (the Janus kinase inhibitor) quells antibody responses to an immunotoxin derived from the bacterial protein, Pseudomonas exotoxin A, as well as to the model antigen, keyhole limpet hemocyanin. Thousandfold reductions in IgG1 titers to both antigens were observed 21 days post-immunization. In fact, suppression was evident for all IgG isotypes and IgM. A reduction in IgG3 production was also noted with a thymus-independent type II antigen. Mechanistic investigations revealed that tofacitinib treatment led to reduced numbers of CD127+ pro-B cells. Furthermore, we observed fewer germinal center B cells and the impaired formation of germinal centers of mice treated with tofacitinib. Since normal immunoglobulin levels were still present during the tofacitinib treatment, this agent specifically reduced anti-drug antibodies, thus preserving the potential efficacy of biological therapeutics, including those that are used as cancer therapeutics. PMID:24890727

Arctigenin suppresses unfolded protein response and sensitizes glucose deprivation-mediated cytotoxicity of cancer cells.

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Sun, Shengrong; Wang, Xiong; Wang, Changhua; Nawaz, Ahmed; Wei, Wen; Li, Juanjuan; Wang, Lijun; Yu, De-Hua

2011-01-01

The involvement of unfolded protein response (UPR) activation in tumor survival and resistance to chemotherapies suggests a new anticancer strategy targeting UPR pathway. Arctigenin, a natural product, has been recently identified for its antitumor activity with selective toxicity against cancer cells under glucose starvation with unknown mechanism. Here we found that arctigenin specifically blocks the transcriptional induction of two potential anticancer targets, namely glucose-regulated protein-78 (GRP78) and its analog GRP94, under glucose deprivation, but not by tunicamycin. The activation of other UPR pathways, e.g., XBP-1 and ATF4, by glucose deprivation was also suppressed by arctigenin. A further transgene experiment showed that ectopic expression of GRP78 at least partially rescued arctigenin/glucose starvation-mediated cell growth inhibition, suggesting the causal role of UPR suppression in arctigenin-mediated cytotoxicity under glucose starvation. These observations bring a new insight into the mechanism of action of arctigenin and may lead to the design of new anticancer therapeutics. © Georg Thieme Verlag KG Stuttgart · New York.

Mitochondrion-Permeable Antioxidants to Treat ROS-Burst-Mediated Acute Diseases

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Zhong-Wei Zhang

2016-01-01

Full Text Available Reactive oxygen species (ROS play a crucial role in the inflammatory response and cytokine outbreak, such as during virus infections, diabetes, cancer, cardiovascular diseases, and neurodegenerative diseases. Therefore, antioxidant is an important medicine to ROS-related diseases. For example, ascorbic acid (vitamin C, VC was suggested as the candidate antioxidant to treat multiple diseases. However, long-term use of high-dose VC causes many side effects. In this review, we compare and analyze all kinds of mitochondrion-permeable antioxidants, including edaravone, idebenone, α-Lipoic acid, carotenoids, vitamin E, and coenzyme Q10, and mitochondria-targeted antioxidants MitoQ and SkQ and propose astaxanthin (a special carotenoid to be the best antioxidant for ROS-burst-mediated acute diseases, like avian influenza infection and ischemia-reperfusion. Nevertheless, astaxanthins are so unstable that most of them are inactivated after oral administration. Therefore, astaxanthin injection is suggested hypothetically. The drawbacks of the antioxidants are also reviewed, which limit the use of antioxidants as coadjuvants in the treatment of ROS-associated disorders.

Application of response surface methodology to optimize pressurized liquid extraction of antioxidant compounds from sage (Salvia officinalis L.), basil (Ocimum basilicum L.) and thyme (Thymus vulgaris L.).

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Hossain, M B; Brunton, N P; Martin-Diana, A B; Barry-Ryan, C

2010-12-01

The present study optimized pressurized liquid extraction (PLE) conditions using Dionex ASE® 200, USA to maximize the antioxidant activity [Ferric ion Reducing Antioxidant Power (FRAP)] and total polyphenol content (TP) of the extracts from three spices of Lamiaceae family (sage, basil and thyme). Optimal conditions with regard to extraction temperature (66-129 °C) and solvent concentration (32-88% methanol) were identified using response surface methodology (RSM). For all three spices, results showed that 129 °C was the optimum temperature with regard to antioxidant activity. Optimal methanol concentrations with respect to the antioxidant activity of sage and basil extracts were 58% and 60% respectively. Thyme showed a different trend with regard to methanol concentration and was optimally extracted at 33%. Antioxidant activity yields of the optimal PLE were significantly (p < 0.05) higher than solid/liquid extracts. Predicted models were highly significant (p < 0.05) for both total phenol (TP) and FRAP values in all the spices with high regression coefficients (R(2)) ranging from 0.651 to 0.999.

Evidence that shock-induced immune suppression is mediated by adrenal hormones and peripheral beta-adrenergic receptors.

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Cunnick, J E; Lysle, D T; Kucinski, B J; Rabin, B S

1990-07-01

Our previous work has demonstrated that presentations of mild foot-shock to Lewis rats induces a suppression of splenic and peripheral blood lymphocyte responses to nonspecific T-cell mitogens. The present study demonstrated that adrenalectomy prevented the shock-induced suppression of the mitogenic response of peripheral blood T-cells but did not attenuate the suppression of splenic T-cells. Conversely, the beta-adrenergic receptor antagonists, propranolol and nadolol, attenuated the shock-induced suppression of splenic T-cells in a dose-dependent manner but did not attenuate suppression of the blood mitogen response. These data indicate that distinct mechanisms mediate the shock-induced suppression of T-cell responsiveness to mitogens in the spleen and the peripheral blood. The results indicate that the peripheral release of catecholamines is responsible for splenic immune suppression and that adrenal hormones, which do not interact with beta-adrenergic receptors, are responsible for shock-induced suppression of blood mitogenic responses.

Effects of Puerariae Radix extract on the activity of antioxidant

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Young-Joon Eun

2007-12-01

Full Text Available Objective : The objective of this study was to investigate the antioxidative effects of Puerariae Radix extract. Method : Total antioxidant capacity (TAC, Total antioxidant response (TAR, Total phenolic content, Reactive oxygen species (ROS, 1,1-Diphenyl-2-picrylhydrazyl (DPPH free radical scavenging activities, lipid peroxidation were examined. Result : Total antioxidant status was examined by total antioxidant capacity(TAC and total antioxidant response(TAR against potent free radical reactions. TAC and TAR of Puerariae Radix extract at the concentration of 5 mg/㎖ were 2.02 and 1.50 mM Trolox equivalents, respectively. Total phenolic content of Puerariae Radix extract at the concentration of 5mg/㎖ was 2.29 mM gallic acid equivalent. Concentration of Puerariae Radix extract at which DPPH radical scavenging activity was inhibited by 50% was 5.91 mg/㎖ as compared to 100% by pyrogallol solution as a reference. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeSO4/ascorbic acid. Puerariae Radix extract at the concentration of 1 mg/㎖ slightly but significantly decreased TBARS concentration. The extract further prevented lipid peroxidation in a dose-dependent manner. The effect of Puerariae Radix extract on reactive oxygen species (ROS generation was examined using cell-free system induced by hydrogen peroxide/FeSO4. Addition of 1 mg/㎖ of Puerariae Radix extract significantly reduced dichloroflurescein (DCF fluorescence. The extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the extract significantly prevented ROS generation in vitro. Thus antioxidant effects of Puerariae Radix extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation, followed by inhibition of lipid peroxidation. Conclusion : As a result, Puerariae Radix seems to have antioxitative effect and antioxidant compount.

Oxidant and antioxidant activities of different anesthetic techniques. Propofol versus desflurane

International Nuclear Information System (INIS)

Ceylan, Berit G.; Yilmaz, Funda; Eroglu, Fusun; Yavuz, Lutfi; Gulmen, Senol; Vural, Huseyin

2009-01-01

To investigate the correlation between propofol and desflurane in terms of lipid peroxidation and antioxidant activity and to search the possible antioxidant anesthesia technique. The study was performed in the Department of Anesthesia and Reanimation, Medical Faculty, Suleyman Demirel University, Isparta, Turkey, between January 2006 and July 2006. Thirty, ASA I-II patients, with an age range of 19-55 years, undergoing elective surgery under general anesthesia were randomized to receive either propofol infusion (Group P) or desflurane inhalation (Group D) following standard induction. Malondialdehyde (MDA), glutathione peroxidase (GSH), super oxide dismutase (SOD) and alpha-tocopherol (Vitamin E) were measured preoperatively, at peroperatively first hour and postoperatively 12-hour. Malondialdehyde was found lower peroperatively in Group P compared to Group D (p<0.05). In Group D, Vitamin E levels were decreased significantly peroperatively compared to preoperative period (p=0.001). We observed a systemic oxidative stress increment with desflurane by terms of MDA; a lipid peroxidation product and endogenous antioxidant activity suppression by terms of Vitamin E at only peroperative period. This study may be defined to support the fact that free oxygen radicals were released more by desflurane than propofol. (author)

Antioxidant Phytochemicals for the Prevention and Treatment of Chronic Diseases

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Yu-Jie Zhang

2015-11-01

Full Text Available Overproduction of oxidants (reactive oxygen species and reactive nitrogen species in the human body is responsible for the pathogenesis of some diseases. The scavenging of these oxidants is thought to be an effective measure to depress the level of oxidative stress of organisms. It has been reported that intake of vegetables and fruits is inversely associated with the risk of many chronic diseases, and antioxidant phytochemicals in vegetables and fruits are considered to be responsible for these health benefits. Antioxidant phytochemicals can be found in many foods and medicinal plants, and play an important role in the prevention and treatment of chronic diseases caused by oxidative stress. They often possess strong antioxidant and free radical scavenging abilities, as well as anti-inflammatory action, which are also the basis of other bioactivities and health benefits, such as anticancer, anti-aging, and protective action for cardiovascular diseases, diabetes mellitus, obesity and neurodegenerative diseases. This review summarizes recent progress on the health benefits of antioxidant phytochemicals, and discusses their potential mechanisms in the prevention and treatment of chronic diseases.

Gender and suppression of mid-latency ERP components during stress.

Science.gov (United States)

White, Patricia M; Kanazawa, Asako; Yee, Cindy M

2005-11-01

Substantial research evidence suggests that women may be more reactive to stress than men. This study examined the influence of gender and stress on suppression of the P50 and N100 components of the auditory event-related potential. During a stressor task, women (n=13) showed disrupted P50 and N100 suppression whereas men (n=15) exhibited only alterations in N100 suppression. Additionally, reduced skin conductance level during stress correlated with impaired P50 suppression and elevated Click 2 amplitude of the P50 response in women. These data suggest that gender differences in response to perceived stress may be an important factor to consider in studies relying upon the P50 suppression paradigm.

BIOCHEMICAL EVALUATION OF CUMIN (CUMINUM CYMINUM) AND MARJORAM (MARJORANA HORTENSIS) AS NATURAL ANTIOXIDANTS

Energy Technology Data Exchange (ETDEWEB)

MAHMOUD, K A; HAMZA, R G [Food Irradiation Research Dept., National Centre for Radiation Research and Technology, Atomic Energy Authority, Cairo, (Egypt)

2009-07-01

Hypercholesterolemia, high cholesterol diet and oxidative stress increase serum total cholesterol and LDL-cholesterol levels resulting in increased risk for development of atherosclerosis. Antioxidants play an important role in inhibiting and scavenging free radicals, thus, providing protection to humans against infectious and degenerative diseases. Several studies showed that the antioxidant activity is high in medicinal plants. The present study was carried out to determine the effect of using cumin or marjoram as supplement on serum lipid levels, serum glucose and serum lipid peroxidation in hypercholesterolemic rats. GC-MS for analysis of essential oil showed that the number of identified compounds was 18; the most important were alpha-trepenol, linalool and gamma-terpinene (natural antioxidants). Hypercholesterolemic diet (HCD) containing cholesterol (1% w/w) and sodium cholate (0.2% w/w) was investigated on male rats. Cumin or marjoram (1% w/w) was added to the HCD as a decontaminated supplement to evaluate the efficacy of these medicinal plants in reducing hypercholesterolemia. Their effects on serum lipid, blood lipid peroxidation and antioxidant properties were determined. It was found that the use of either cumin or marjoram reduced TG, TC, LDL-C and glucose level and increased HDL-C. Also, these medicinal plants suppressed lipid peroxidation via enhancement of antioxidant activities. It could be concluded that intake of cumin or marjoram may minimize the risk of atherosclerosis associated with a high cholesterol diet. These overall results support the future use of these medicinal plants as natural antioxidants and the continuous medicinal plants intake may be recommended as food supplement.

BIOCHEMICAL EVALUATION OF CUMIN (CUMINUM CYMINUM) AND MARJORAM (MARJORANA HORTENSIS) AS NATURAL ANTIOXIDANTS

International Nuclear Information System (INIS)

MAHMOUD, K.A.; HAMZA, R.G.

2009-01-01

Hypercholesterolemia, high cholesterol diet and oxidative stress increase serum total cholesterol and LDL-cholesterol levels resulting in increased risk for development of atherosclerosis. Antioxidants play an important role in inhibiting and scavenging free radicals, thus, providing protection to humans against infectious and degenerative diseases. Several studies showed that the antioxidant activity is high in medicinal plants. The present study was carried out to determine the effect of using cumin or marjoram as supplement on serum lipid levels, serum glucose and serum lipid peroxidation in hypercholesterolemic rats. GC-MS for analysis of essential oil showed that the number of identified compounds was 18; the most important were α-trepenol, linalool and γ-terpinene (natural antioxidants). Hypercholesterolemic diet (HCD) containing cholesterol (1% w/w) and sodium cholate (0.2% w/w) was investigated on male rats. Cumin or marjoram (1% w/w) was added to the HCD as a decontaminated supplement to evaluate the efficacy of these medicinal plants in reducing hypercholesterolemia. Their effects on serum lipid, blood lipid peroxidation and antioxidant properties were determined. It was found that the use of either cumin or marjoram reduced TG, TC, LDL-C and glucose level and increased HDL-C. Also, these medicinal plants suppressed lipid peroxidation via enhancement of antioxidant activities. It could be concluded that intake of cumin or marjoram may minimize the risk of atherosclerosis associated with a high cholesterol diet. These overall results support the future use of these medicinal plants as natural antioxidants and the continuous medicinal plants intake may be recommended as food supplement.

Thioredoxin-albumin fusion protein prevents copper enhanced zinc-induced neurotoxicity via its antioxidative activity.

Science.gov (United States)

Tanaka, Ken-Ichiro; Shimoda, Mikako; Chuang, Victor T G; Nishida, Kento; Kawahara, Masahiro; Ishida, Tatsuhiro; Otagiri, Masaki; Maruyama, Toru; Ishima, Yu

2018-01-15

Zinc (Zn) is a co-factor for a vast number of enzymes, and functions as a regulator for immune mechanism and protein synthesis. However, excessive Zn release induced in pathological situations such as stroke or transient global ischemia is toxic. Previously, we demonstrated that the interaction of Zn and copper (Cu) is involved in the pathogenesis of Alzheimer's disease and vascular dementia. Furthermore, oxidative stress has been shown to play a significant role in the pathogenesis of various metal ions induced neuronal death. Thioredoxin-Albumin fusion (HSA-Trx) is a derivative of thioredoxin (Trx), an antioxidative protein, with improved plasma retention and stability of Trx. In this study, we examined the effect of HSA-Trx on Cu 2+ /Zn 2+ -induced neurotoxicity. Firstly, HSA-Trx was found to clearly suppress Cu 2+ /Zn 2+ -induced neuronal cell death in mouse hypothalamic neuronal cells (GT1-7 cells). Moreover, HSA-Trx markedly suppressed Cu 2+ /Zn 2+ -induced ROS production and the expression of oxidative stress related genes, such as heme oxygenase-1. In contrast, HSA-Trx did not affect the intracellular levels of both Cu 2+ and Zn 2+ after Cu 2+ /Zn 2+ treatment. Finally, HSA-Trx was found to significantly suppress endoplasmic reticulum (ER) stress response induced by Cu 2+ /Zn 2+ treatment in a dose dependent manner. These results suggest that HSA-Trx counteracted Cu 2+ /Zn 2+ -induced neurotoxicity by suppressing the production of ROS via interfering the related gene expressions, in addition to the highly possible radical scavenging activity of the fusion protein. Based on these findings, HSA-Trx has great potential as a promising therapeutic agent for the treatment of refractory neurological diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

Total antioxidant capacity in children with acute appendicitis.

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Kaya, M; Boleken, M E; Kanmaz, T; Erel, O; Yucesan, S

2006-02-01

This study aimed to investigate antioxidant capacity by using a novel automated method in children with acute appendicitis. Blood samples were obtained from consecutive patients with acute appendicitis (appendicitis group, n = 12) and acute abdominal pain due to non surgical disease (non-appendicitis group, n = 11), and from patients with inguinal hernia (healthy group, n = 12) as the control group. At admission, total antioxidant capacity (TAC) levels of plasma were evaluated in all patients by a method recently developed by Erel. Four other major individual plasma antioxidant components, the levels of total protein, albumin, uric acid and bilirubin, were also evaluated. Total antioxidant capacity in patients with acute appendicitis was statistically compared with the two other groups. While the TAC level in the appendicitis group was significantly greater than in the non-appendicitis group, no significant difference was found in healthy groups (p 0.05, 1.94 +/- 0.38, 1.40 +/- 0.36, and 1.99 +/- 0.35 respectively). Individual components of total antioxidant capacity, i.e. total protein, albumin, uric acid and bilirubin concentrations, were also higher in the patients with acute appendicitis than those of the other two control groups. Our data show that children with acute appendicitis do not have deficient blood plasma antioxidant capacity. These results provide evidence that acute appendicitis results in more induction of antioxidative response than non-surgical diseases.

Antioxidant Capacities of Fractions of Bamboo Shaving Extract and Their Antioxidant Components.

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Gong, Jinyan; Huang, Jun; Xiao, Gongnian; Chen, Feng; Lee, Bolim; Ge, Qing; You, Yuru; Liu, Shiwang; Zhang, Ying

2016-07-30

This research was conducted for evaluation of antioxidant activities of four fractions from bamboo shavings extract (BSE) and their antioxidant components. The antioxidant capacities of BSE and four fractions on ABTS, DPPH, FRAP and total antioxidant capacity assays exhibited the following descending order: DF > n-butanol fraction (BF) > BSE ≈ ethyl acetate fraction (AF) > water fraction (WF). Among the identified phenolic compounds, caffeic acid exhibited the highest antioxidant capacities on DPPH, FRAP and total antioxidant capacity assays. An extremely significant positive correlation between the antioxidant activities with the contents of total flavonoids, total phenolic acids, or total phenolics was observed in this study. The result indicated that the bamboo shaving extract and its solvent fractions could act as natural antioxidants in light of their potent antioxidant activities.

Oxidative stress and antioxidant status response of handball athletes: implications for sport training monitoring.

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Marin, Douglas Popp; Bolin, Anaysa Paola; Campoio, Thais Regina; Guerra, Beatriz Alves; Otton, Rosemari

2013-10-01

The chronic exposure to regular exercise training seems to improve antioxidant defense systems. However, the intense physical training imposed on elite athletes may lead to overtraining associated with oxidative stress. The purpose of the present study was to investigate the effect of different training loads and competition on oxidative stress, biochemical parameters and antioxidant enzymatic defense in handball athletes during 6-months of monitoring. Ten male elite handball athletes were recruited to the study. Blood samples were collected four times every six weeks throughout the season. During most intense periods of training and competitions there were significant changes in plasma indices of oxidative stress (increased TBARS and decreased thiols). Conversely, chronic adaptations to exercise training demonstrated a significant protective effect against oxidative stress in erythrocyte (decrease in TBARs and carbonyl group levels). Erythrocyte antioxidant enzyme activities were significantly increased, suggesting a training-induced antioxidant adaptation. Biomarkers of skeletal muscle damage were significantly increased during high-intensity training period (creatine kinase, lactate dehydrogenase and aspartate aminotransferase). No significant changes were observed in plasma IL-6, TNF-α and uric acid, whereas a significant reduction was found in the IL-1β concentration and gamma-glutamyl transferase activity. Oxidative stress and antioxidant biomarkers can change throughout the season in competitive athletes, reflecting the physical stress and muscle damage that occurs as the result of competitive handball training. In addition, these biochemical measurements can be applied in the physiological follow-up of athletes. © 2013.

Sulphonylurea usage in melioidosis is associated with severe disease and suppressed immune response.

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Xiang Liu

2014-04-01

Full Text Available BACKGROUND: Melioidosis is a problem in the developing tropical regions of Southeast Asia and Northern Australia where the the Gram negative saprophytic bacillus Burkholderia pseudomallei is endemic with the risk of fulminant septicaemia. While diabetes mellitus is a well-established risk factor for melioidiosis, little is known if specific hypoglycemic agents may differentially influence the susceptibility and clinical course of infection with B. pseudomallei (Bp. METHODOLOGY/PRINCIPAL FINDINGS: In this cohort study, patients with pre-existing diabetes and melioidosis were retrospectively studied. OUTCOME MEASURES: mortality, length of stay and development of complications (namely hypotension, intubation, renal failure and septicaemia were studied in relation to prior diabetic treatment regimen. Peripheral blood mononuclear cells (PBMC from diabetic patients and healthy PBMC primed with metformin, glyburide and insulin were stimulated with purified Bp antigens in vitro. Immune response and specific immune pathway mediators were studied to relate to the clinical findings mechanistically. Of 74 subjects, 44 (57.9% had sulphonylurea-containing diabetic regimens. Patient receiving sulphonylureas had more severe septic complications (47.7% versus 16.7% p = 0.006, in particular, hypotension requiring intropes (p = 0.005. There was also a trend towards increased mortality in sulphonylurea-users (15.9% versus 3.3% p = 0.08. In-vitro, glyburide suppressed inflammatory cytokine production in a dose-dependent manner. An effect of the drug was the induction of IL-1R-associated kinase-M at the level of mRNA transcription. CONCLUSION/SIGNIFICANCE: Sulphonylurea treatment results in suppression of host inflammatory response and may put patients at higher risk for adverse outcomes in melioidosis.

Effects of dietary chitosan on growth, lipid metabolism, immune response and antioxidant-related gene expression in Misgurnus anguillicaudatus.

Science.gov (United States)

Yan, J; Guo, C; Dawood, M A O; Gao, J

2017-05-30

This study was performed to evaluate the effects of dietary chitosan supplementation on growth performance, lipid metabolism, gut microbial, antioxidant status and immune responses of juvenile loach (Misgurnus anguillicaudatus). Five experimental diets were formulated to contain graded levels of chitosan (0 (control), 0.5, 1, 2 and 5% CHI) for 50 days. Results of the present study showed that body weight gain was significantly higher in fish fed chitosan supplemented diets in dose dependent manner than control group. Increasing dietary chitosan levels reduced gut lipid content. Meanwhile the mRNA expression levels of intestine lipoprotein lipase and fatty acid binding protein 2 were significantly reduced with incremental dietary chitosan level. The percentages of total monounsaturated fatty acid decreased, while polyunsaturated fatty acid increased with dietary chitosan. The fish fed 0.5% CHI had higher mucus lysozyme activity (LZM) than those fed 0% CHI, but the LZM activity was significantly decreased with advancing chitosan supplement. The expression levels of superoxide dismutase, catalase and glutathione peroxidase revealed a similar trend, where the highest expressions were found in fish fed 5% CHI diet. In the term of intestine microbiota between 0 and 1% CHI groups, the proportion of bacteria in the phylum Bacteroidetes increased, whereas the proportion of bacteria in the phylum Firmicutes decreased as the fish supplemented chitosan. In conclusion, supplementation of chitosan improved growth performance, antioxidant status and immunological responses in loach.

Ah receptor mediated suppression of the antibody response in mice is primarily dependent on the Ah phenotype of lymphoid tissue

International Nuclear Information System (INIS)

Silkworth, J.B.; Antrim, L.A.; Sack, G.

1986-01-01

Halogenated aromatic hydrocarbons act through the aromatic hydrocarbon (Ah) receptor in mice to produce a series of toxic effects of the immune system. The receptor protein is a product of the Ah gene locus. Ah responsive (Ahb/Ahb) mice express a high affinity receptor in both lymphoid and nonlymphoid tissues whereas nonresponsive Ahd/Ahd mice express a poor affinity receptor. To determine the role of the Ah receptor of lymphoid tissue relative to that of nonlymphoid tissue in the induction of immune impairment, bone marrow was used to reconstitute lethally irradiated mice of the same or opposite Ah phenotype. All mice were given 3,3',4,4'-tetrachlorobiphenyl (35 and 350 mumol/kg) ip 2 days before immunization with sheep erythrocytes (SRBC). The immune response to this T dependent antigen and organ weights were determined 5 or 7 days later in normal or chimeric mice, respectively. Monoclonal Lyt 1.1 and Lyt 1.2 antibodies were used to establish the origin of the cells which repopulated the chimeric thymuses. The immune responses of both BALB/cBy (Ahb/Ahb) and the BALB/cBy X DBA/2 hybrid, CByD2F1 (Ahb/Ahd), were significantly suppressed but DBA/2 mice were unaffected. The immune responses of chimeric BALB/cBy----BALB/cBy and BALB/cBy----DBA/2 (donor----recipient) mice were also significantly suppressed and thymic atrophy was observed in both cases. The serum anti-SRBC antibody titers of DBA/2----BALB/cBy chimeras were also significantly decreased although not to the same extent as in BALB/cBy----DBA/2 mice. Chimeric DBA/2----DBA/2 mice were not affected. These results indicate that the sensitivity to Ah receptor mediated suppression of the antibody response is primarily determined by the Ah phenotype of the lymphoid tissue

Anti-epileptogenic and antioxidant effect of Lavandula officinalis aerial part extract against pentylenetetrazol-induced kindling in male mice.

Science.gov (United States)

Rahmati, Batool; Khalili, Mohsen; Roghani, Mehrdad; Ahghari, Parisa

2013-06-21

Repeated application of Lavandula officinalis (L. officinalis) has been recommended for a long time in Iranian traditional medicine for some of nervous disorders like epilepsy and dementia. However, there is no available report for the effect of chronic administration of Lavandula extract in development (acquisition) of epilepsy. Therefore, this study was designed to investigate the anti-epileptogenic and antioxidant activity of repeated administration of Lavandula officinalis extract on pentylenetetrazol (PTZ) kindling seizures in mice model. Lavandula officinalis was tested for its ability (i) to suppress the seizure intensity and lethal effects of PTZ in kindled mice (anti-epileptogenic effect), (ii) to attenuate the PTZ-induced oxidative injury in the brain tissue (antioxidant effect) when given as a pretreatment prior to each PTZ injection during kindling development. Valproate (Val), a major antiepileptic drug, was also tested for comparison. Val and Lavandula officinalis extract showed anti-epileptogenic properties as they reduced seizure score of kindled mice and PTZ-induced mortality. In this regard, Lavandula officinalis was more effective than Val. Both Lavandula officinalis and Val suppressed brain nitric oxide (NO) level of kindled mice in comparison with the control and PTZ group. Meanwhile, Lavandula officinalis suppressed NO level more than Val and Lavandula officinalis also decreased brain MDA level relative to PTZ group. This is the first report to demonstrate NO suppressing and anti-epileptogenic effect of chronic administration of Lavandula officinalis extract on acquisition of epilepsy in PTZ kindling mice model. In this regard, Lavandula officinalis extract was more effective than Val, possibly and in part via brain NO suppression. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Antioxidant responses following active and passive smoking of tobacco and electronic cigarettes.

Science.gov (United States)

Poulianiti, Konstantina; Karatzaferi, Christina; Flouris, Andreas D; Fatouros, Ioannis G; Koutedakis, Yiannis; Jamurtas, Athanasios Z

2016-07-01

It has been indicated that acute active and passive tobacco cigarette smoking may cause changes on redox status balance that may result in significant pathologies. However, no study has evaluated the effects of active and passive e-cigarette smoking on redox status of consumers. To examine the acute effects of active and passive e-cigarette and tobacco cigarette smoking on selected redox status markers. Using a randomized single-blind crossover design, 30 participants (15 smokers and 15 nonsmokers) were exposed to three different experimental conditions. Smokers underwent a control session, an active tobacco cigarette smoking session (smoked 2 cigarettes within 30-min) and an active e-cigarette smoking session (smoked a pre-determined number of puffs within 30-min using a liquid with 11 ng/ml nicotine). Similarly, nonsmokers underwent a control session, a passive tobacco cigarette smoking session (exposure of 1 h to 23 ± 1 ppm of CO in a 60 m(3) environmental chamber) and a passive e-cigarette smoking session (exposure of 1 h to air enriched with pre- determined number of puffs in a 60 m(3) environmental chamber). Total antioxidant capacity (TAC), catalase activity (CAT) and reduced glutathione (GSH) were assessed in participants' blood prior to, immediately after, and 1-h post-exposure. TAC, CAT and GSH remained similar to baseline levels immediately after and 1-h-post exposure (p > 0.05) in all trials. Tobacco and e-cigarette smoking exposure do not acutely alter the response of the antioxidant system, neither under active nor passive smoking conditions. Overall, there is not distinction between tobacco and e-cigarette active and passive smoking effects on specific redox status indices.

Preliminary Characterization, Antioxidant and Hepatoprotective Activities of Polysaccharides from Taishan Pinus massoniana Pollen

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Changming Zhou

2018-01-01

Full Text Available The objectives of the present study were to characterize the chemical composition, antioxidant activity and hepatoprotective effect of the polysaccharides from Taishan Pinus massoniana pollen (TPPPS. HPLC analysis showed that TPPPS was an acidic heteropolysaccharide with glucose and arabinose as the main component monosaccharides (79.6%, molar percentage. Fourier transform-infrared spectroscopy (FT-IR analysis indicated that the spectra of TPPPS displayed infrared absorption peaks characteristic of polysaccharides. In in vitro assays TPPPS exhibited different degrees of dose-dependent antioxidant activities , and this was further verified by suppression of CCl4-induced oxidative stress in the liver with three tested doses of TPPPS (100, 200, and 400 mg/kg bw in rats. Pretreatment with TPPPS significantly decreased the levels of alanine aminotransferase (AST, aspartate aminotransferase (ALT, alkaline phosphatase (ALP, lactic dehydrogenase (LDH and malondialdehyde (MDA against CCl4 injuries, and elevated the activities of superoxide dismutase (SOD as well as glutathione peroxidase (GSH-Px. Histopathological observation further confirmed that TPPPS could protect the liver tissues from CCl4-induced histological alternation. These results suggest that TPPPS has strong antioxidant activities and significant protective effect against acute hepatotoxicity induced by CCl4. The hepatoprotective effect may partly be related to its free radical scavenging effect, increasing antioxidant activity and inhibiting lipid peroxidation.

A Specific Melon Concentrate Exhibits Photoprotective Effects from Antioxidant Activity in Healthy Adults

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Laure Egoumenides

2018-03-01

Full Text Available Skin is the largest body organ and the first barrier to exogenous threats. This organ is constantly exposed to external factors such as ultraviolet radiation, which induces many adverse effects including sunburn, depigmentation, photo aging, photo immune suppression, and even skin cancer. Antioxidants seem to be good candidates in order to reduce ultraviolet-mediated damages and to prevent the health consequences of ultraviolet exposure. The present investigation aims to further characterize the potential skin photoprotective effects of a food supplementation and a topical administration of a melon concentrate alone or in combination. A clinical study assessing the Minimal Erythema Dose (MED was first set up to evaluate photoprotection. Afterward, an independent in vitro study was performed on human skin explants from a donor to evaluate the effect of the melon concentrate at different levels including on the sunburn cells formation and on the endogenous antioxidant enzymes and its influence on melanin. Clinical study results demonstrate that melon concentrate application and/or supplementation increased MED. It also increased the endogenous antioxidant enzymes and reduced sunburn cells and melanin level on irradiated skin explants. Therefore, it is suggested that melon concentrate administration (oral and/or topical could be a useful strategy for photoprotection due to its antioxidant properties.

T-2 toxin impairment of enteric reovirus clearance in the mouse associated with suppressed immunoglobulin and IFN-γ responses

International Nuclear Information System (INIS)

Li Maoxiang; Cuff, Christopher F.; Pestka, James J.

2006-01-01

Trichothecenes are exquisitely toxic to the gastrointestinal (GI) tract and leukocytes and thus are likely to impair gut immunity. The purpose of this research was to test the hypothesis that the Type A trichothecene T-2 toxin interferes with the gut mucosal immune response to enteric reovirus infection. Mice were exposed i.p. first to 1.75 mg/kg bw T-2 and then 2 h later with 3 x 10 7 plaque-forming units of reovirus serotype 1, strain Lang (T1/L). As compared to vehicle-treated control, T-2-treated mice had dramatically elevated intestinal plaque-forming viral titers after 5 days and failed to completely clear the virus from intestine by 10 days. Levels of reovirus λ2 core spike (L2 gene) RNA in feces in T-2-treated mice were significantly higher at 1, 3, 5, and 7 days than controls. T-2 potentiated L2 mRNA expression in a dose-dependent manner with as little as 50 μg/kg of the toxin having a potentiative effect. T-2 exposure transiently suppressed induction of reovirus-specific IgA in feces (6 and 8 days) as well as specific IgA and IgG 2a in serum (5 days). This suppression corresponded to decreased secretion of reovirus-specific IgA and IgG 2a in Peyer's patch (PP) and lamina propria fragment cultures prepared 5 days after infection. T-2 suppressed IFN-γ responses in PP to reovirus at 3 and 7 days as compared to infected controls whereas IL-2 mRNA concentrations were unaffected. PP IL-6 mRNA levels were increased 2-fold 2 h after T-2 treatment, but no differences between infected T-2-exposed and infected vehicle-treated mice were detectable over the next 7 days. Overall, the results suggest that T-2 toxin increased both the extent of GI tract reovirus infection and fecal shedding which corresponded to both suppressed immunoglobulin and IFN-γ responses

Antioxidant and anti-osteoporotic effects of anthraquinones and related constituents from the aqueous dissolved Aloe exudates.

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Sun, Ya Nan; Li, Wei; Lee, Sang Hyun; Jang, Hae Dong; Ma, Jin Yeul; Kim, Young Ho

2017-12-01

In this study, 25 known anthraquinones and related compounds were isolated from aqueous dissolved Aloe exudates. The antioxidant and anti-osteoporotic activities of the isolated compounds were then investigated. Compounds 8, 11, 20, and 23 showed good antioxidant activity based on peroxyl radical-scavenging and reducing capacity assays at a concentration of 10.0 μM. Additionally, compounds 7, 9, 15-16, 18, 21-22 and 24-25 showed potent peroxyl radical-scavenging activities with values ranging from 5.28 to 14.60 at 10.0 μM. Moreover, compounds 8, 11, 15, 20 and 22 exhibited significantly suppressed tartrate-resistant acid phosphatase (TRAP) activity in nuclear factor-κB ligand-activated osteoclastic RAW 264.7 cells, with values of 125.67, 118.54, 127.64, 125.82 and 124.98%, respectively. These results indicate that Aloe is an excellent source of antioxidant and anti-osteoporotic phytochemicals.

17β-Estradiol up-regulates Nrf2 via PI3K/AKT and estrogen receptor signaling pathways to suppress light-induced degeneration in rat retina.

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Zhu, C; Wang, S; Wang, B; Du, F; Hu, C; Li, H; Feng, Y; Zhu, R; Mo, M; Cao, Y; Li, A; Yu, X

2015-09-24

Human age-related retinal diseases, such as age-related macular degeneration (AMD), are intimately associated with decreased tissue oxygenation and hypoxia. Different antioxidants have been investigated to reverse AMD. In the present study, we describe the antioxidant 17β-estradiol (βE2) and investigate its protective effects on retinal neurons. Fourteen days after ovariectomy, adult Sprague-Dawley rats were exposed to 8000-lux light for 12h to induce retinal degeneration. Reactive oxygen species (ROS) levels were assessed by confocal fluorescence microscopy using 2,7-dichlorofluorescein diacetate. Nuclear factor erythroid 2-related factor 2 (Nrf2) and antioxidant enzyme mRNA expression were detected by real-time PCR. Western blotting was used to evaluate NRF2 activation. NRF2 translocation was determined by immunohistochemistry, with morphological changes monitored by hematoxylin and eosin staining. Following light exposure, βE2 significantly reduced ROS production. βE2 also up-regulated NRF2 mRNA and protein levels, with maximal expression at 4 and 12h post-exposure, respectively. Interestingly, following βE2 administration, NRF2 was translocated from the cytoplasm to the nucleus, primarily in the outer nuclear layer. βE2 also up-regulated NRF2, which triggered phase-2 antioxidant enzyme expression (superoxide dismutases 1 and 2, catalase, glutaredoxins 1 and 2, and thioredoxins 1 and 2), reduced ROS production, and ameliorated retinal damage. However, the beneficial effects of βE2 were markedly suppressed by pretreatment with LY294002 or ICI182780, specific inhibitors of the phosphatidylinositol 3-kinase-Akt (PI3K/AKT), and estrogen receptor (ER) signaling pathways, respectively. Taken together, these observations suggest that βE2 exerts antioxidative effects following light-induced retinal degeneration potentially via NRF2 activation. This protective mechanism may depend on two pathways: a rapid, non-genomic-type PI3K/AKT response, and a genomic-type ER

Mitochondrial reactive oxygen species mediate the lipopolysaccharide-induced pro-inflammatory response in human gingival fibroblasts

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Li, Xue; Wang, Xiaoxuan [Department of Periodontology, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Zheng, Ming, E-mail: zhengm@bjmu.edu.cn [Department of Physiology and Pathophysiology, Peking University Health Science Center, 38 Xueyuan Road, Haidian District, Beijing 100191 (China); Luan, Qing Xian, E-mail: kqluanqx@126.com [Department of Periodontology, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China)

2016-09-10

Although periodontal diseases are initiated by bacteria that colonize the tooth surface and gingival sulcus, the host response is believed to play an essential role in the breakdown of connective tissue and bone. Mitochondrial reactive oxygen species (mtROS) have been proposed to regulate the activation of the inflammatory response by the innate immune system. However, the role of mtROS in modulating the response of human gingival fibroblasts (HGFs) to immune stimulation by lipopolysaccharides (LPS) has yet to be fully elucidated. Here, we showed that LPS from Porphyromonas gingivalis stimulated HGFs to increase mtROS production, which could be inhibited by treatment with a mitochondrial-targeted exogenous antioxidant (mito-TEMPO) or transfection with manganese superoxide dismutase (MnSOD). A time-course study revealed that an increase in the concentration of mtROS preceded the expression of inflammatory cytokines in HGFs. Mito-TEMPO treatment or MnSOD transfection also significantly prevented the LPS-induced increase of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. Furthermore, suppressing LPS-induced mtROS generation inhibited the activation of p38, c-Jun N-terminal kinase, and inhibitor of nuclear factor-κB kinase, as well as the nuclear localization of nuclear factor-κB. These results demonstrate that mtROS generation is a key signaling event in the LPS-induced pro-inflammatory response of HGFs. - Highlights: • Inflammation is thought to promote pathogenic changes in periodontitis. • We investigated mtROS as a regulator of inflammation in gingival fibroblasts. • Targeted antioxidants were used to inhibit mtROS production after LPS challenge. • Inhibiting mtROS generation suppressed the secretion of pro-inflammatory cytokines. • JNK, p38, IKK, and NF-κB were shown to act as transducers of mtROS signaling.

Mitochondrial reactive oxygen species mediate the lipopolysaccharide-induced pro-inflammatory response in human gingival fibroblasts

International Nuclear Information System (INIS)

Li, Xue; Wang, Xiaoxuan; Zheng, Ming; Luan, Qing Xian

2016-01-01

Although periodontal diseases are initiated by bacteria that colonize the tooth surface and gingival sulcus, the host response is believed to play an essential role in the breakdown of connective tissue and bone. Mitochondrial reactive oxygen species (mtROS) have been proposed to regulate the activation of the inflammatory response by the innate immune system. However, the role of mtROS in modulating the response of human gingival fibroblasts (HGFs) to immune stimulation by lipopolysaccharides (LPS) has yet to be fully elucidated. Here, we showed that LPS from Porphyromonas gingivalis stimulated HGFs to increase mtROS production, which could be inhibited by treatment with a mitochondrial-targeted exogenous antioxidant (mito-TEMPO) or transfection with manganese superoxide dismutase (MnSOD). A time-course study revealed that an increase in the concentration of mtROS preceded the expression of inflammatory cytokines in HGFs. Mito-TEMPO treatment or MnSOD transfection also significantly prevented the LPS-induced increase of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. Furthermore, suppressing LPS-induced mtROS generation inhibited the activation of p38, c-Jun N-terminal kinase, and inhibitor of nuclear factor-κB kinase, as well as the nuclear localization of nuclear factor-κB. These results demonstrate that mtROS generation is a key signaling event in the LPS-induced pro-inflammatory response of HGFs. - Highlights: • Inflammation is thought to promote pathogenic changes in periodontitis. • We investigated mtROS as a regulator of inflammation in gingival fibroblasts. • Targeted antioxidants were used to inhibit mtROS production after LPS challenge. • Inhibiting mtROS generation suppressed the secretion of pro-inflammatory cytokines. • JNK, p38, IKK, and NF-κB were shown to act as transducers of mtROS signaling.

Anti-inflammatory and anti-oxidant activities of olmesartan medoxomil ameliorate experimental colitis in rats

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Nagib, Marwa M. [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Misr International University, Cairo (Egypt); Tadros, Mariane G., E-mail: mirogeogo@yahoo.com [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo (Egypt); ELSayed, Moushira I. [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Misr International University, Cairo (Egypt); Khalifa, Amani E. [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo (Egypt)

2013-08-15

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) driven through altered immune responses with production of proinflammatory cytokines. Many therapies are used, but side effects and loss of response limit long-term effectiveness. New therapeutic strategies are thus needed for patients who don't respond to current treatments. Recently, there is suggested involvement of the proinflammatory hormone angiotensin II in inflammatory bowel disease. The aim of this study was to investigate the possible role of olmesartan medoxomil (OLM-M), an angiotensin II receptor blocker in ameliorating ulcerative colitis. Colitis was induced in male Wistar rats by administration of 5% dextran sodium sulphate (DSS) in drinking water for 5 days. OLM-M (1, 3 and 10 mg/kg) was administered orally during 21 days prior to the induction of colitis, and for 5 days after. Sulfasalazine (500 mg/kg) was used as reference drug. All animals were tested for changes in colon length, disease activity index (DAI) and microscopic damage. Colon tissue concentration/activity of tumor necrosis alpha (TNF-α), myeloperoxidase (MPO), prostaglandin E2 (PGE2), reduced glutathione (GSH) and malondialdehyde (MDA) were assessed. Results showed that the OLM-M dose-dependently ameliorated the colonic histopathological and biochemical injuries, an effect that is comparable or even better than that of the standard sulfasalazine. These results suggest that olmesartan medoxomil may be effective in the treatment of UC through its anti-inflammatory and antioxidant effects. - Highlights: • Olmesartan medoximil reduced dextran sodium sulphate- induced colitis. • Mechanism involved anti-inflammatory and antioxidant effects dose- dependently. • It suppressed malondialdehyde and restored reduced glutathione levels. • It reduced inflammatory markers levels and histological changes.

Rapid upregulation of heart antioxidant enzymes during arousal from estivation in the Giant African snail (Achatina fulica).

Science.gov (United States)

Salway, Kurtis D; Tattersall, Glenn J; Stuart, Jeffrey A

2010-11-01

Estivation is an adaptive response to environments characterized by elevated temperatures and desiccative stress, as may occur during summer dry seasons. Similar to diapause and hibernation, it is characterized by low levels of activity, a drastically suppressed metabolic rate and enhanced stress resistance. We tested the hypothesis that Achatina fulica, a pulmonate land snail, enhances stress resistance during estivation and/or arousal by upregulating intracellular antioxidant defenses in the heart, kidney, hepatopancreas and foot tissues. No statistically significant changes in mitochondrial or cytosolic superoxide dismutase levels or activities, or glutathione peroxidase, glutathione reductase or catalase activities were associated with estivation in any tissue, however. In contrast, during arousal from estivation, activities of several antioxidant enzymes increased in heart, hepatopancreas and foot. In heart, a rapid increase in MnSOD protein levels was observed that peaked at 2h post arousal, but no such change was observed in CuZnSOD protein levels. Glutathione peroxidase activity was upregulated at 1h post arousal and remained elevated until 8h post arousal in heart tissue. Glutathione peroxidase was also upregulated at 24h post arousal in foot tissue. Glutathione reductase activity was upregulated at 4h post arousal in heart and foot tissues whereas catalase activity showed no changes. Markers of lipid peroxidation and protein damage revealed no significant increases during estivation or arousal. Therefore, antioxidant enzymes may play a role in oxidative stress defense specifically during arousal from estivation in A. fulica. Copyright 2010 Elsevier Inc. All rights reserved.

Is there a role for antioxidant carotenoids in limiting self-harming immune response in invertebrates?

Science.gov (United States)

Cornet, Stéphane; Biard, Clotilde; Moret, Yannick

2007-06-22

Innate immunity relies on effectors, which produce cytotoxic molecules that have not only the advantage of killing pathogens but also the disadvantage of harming host tissues and organs. Although the role of dietary antioxidants in invertebrate immunity is still unknown, it has been shown in vertebrates that carotenoids scavenge cytotoxic radicals generated during the immune response. Carotenoids may consequently decrease the self-harming cost of immunity. A positive relationship between the levels of innate immune defence and circulating carotenoid might therefore be expected. Consistent with this hypothesis, we show that the maintenance and use of the prophenoloxidase system strongly correlate with carotenoid concentration in haemolymph within and among natural populations of the crustacean Gammarus pulex.

Antioxidant Activity in Extracts of 27 Indigenous Taiwanese Vegetables

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Pi-Yu Chao

2014-05-01

Full Text Available The objectives of this study were to identify the antioxidants and antioxidant axtivity in 27 of Taiwan’s indigenous vegetables. Lycium chinense (Lc, Lactuca indica (Li, and Perilla ocymoides (Po contained abundant quercetin (Que, while Artemisia lactiflora (Al and Gynura bicolor (Gb were rich in morin and kaempferol, respectively. Additionally, Nymphoides cristata (Nc and Sechium edule (Se-yellow had significantly higher levels of myricetin (Myr than other tested samples. Cyanidin (Cyan and malvidin (Mal were abundant in Gb, Abelmoschus esculentus Moench (Abe, Po, Anisogonium esculentum (Retz. Presl (Ane, Ipomoea batatas (Ib-purple, and Hemerocallis fulva (Hf-bright orange. Relatively high levels of Trolox equivalent antioxidant capacity (TEAC, oxygen radical absorption capacity (ORAC, and 1,1-diphenyl-2-picryl-hydrazyl (DPPH radical scavenger were generated from extracts of Toona sinensis (Ts and Po. Significant and positive correlations between antioxidant activity and polyphenols, anthocyanidins, Que, Myr, and morin were observed, indicating that these phytochemicals were some of the main components responsible for the antioxidant activity of tested plants. The much higher antioxidant activity of Po, Ts, and Ib (purple leaf may be related to their higher Cyan, Que, and polyphenol content.

Thiol dependent NF-κB suppression and inhibition of T-cell mediated adaptive immune responses by a naturally occurring steroidal lactone Withaferin A

Energy Technology Data Exchange (ETDEWEB)

Gambhir, Lokesh; Checker, Rahul; Sharma, Deepak; Thoh, M. [Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai (India); Patil, Anand [Advanced Centre for Treatment Research and Education in Cancer, Kharghar, Navi Mumbai (India); Degani, M. [Institute of Chemical Technology, Matunga, Mumbai (India); Gota, Vikram [Advanced Centre for Treatment Research and Education in Cancer, Kharghar, Navi Mumbai (India); Sandur, Santosh K., E-mail: sskumar@barc.gov.in [Radiation Biology & Health Sciences Division, Bio-science Group, Bhabha Atomic Research Centre, Mumbai (India)

2015-12-01

Withaferin A (WA), a steroidal lactone isolated from ayurvedic medicinal plant Withania somnifera, was shown to inhibit tumor growth by inducing oxidative stress and suppressing NF-κB pathway. However, its effect on T-cell mediated adaptive immune responses and the underlying mechanism has not been investigated. Since both T-cell responses and NF-κB pathway are known to be redox sensitive, the present study was undertaken to elucidate the effect of WA on adaptive immune responses in vitro and in vivo. WA inhibited mitogen induced T-cell and B-cell proliferation in vitro without inducing any cell death. It inhibited upregulation of T-cell (CD25, CD69, CD71 and CD54) and B-cell (CD80, CD86 and MHC-II) activation markers and secretion of Th1 and Th2 cytokines. WA induced oxidative stress by increasing the basal ROS levels and the immunosuppressive effects of WA were abrogated only by thiol anti-oxidants. The redox modulatory effects of WA in T-cells were attributed to its ability to directly interact with free thiols. WA inhibited NF-κB nuclear translocation in lymphocytes and prevented the direct binding of nuclear NF-κB to its consensus sequence. MALDI-TOF analysis using a synthetic NF-κB-p50 peptide containing Cys-62 residue suggested that WA can modify the cysteine residue of NF-κB. The pharmacokinetic studies for WA were also carried out and in vivo efficacy of WA was studied using mouse model of Graft-versus-host disease. In conclusion, WA is a potent inhibitor of T-cell responses and acts via a novel thiol dependent mechanism and inhibition of NF-κB pathway. - Highlights:: • Withaferin A (WA) inhibited T-cell and B-cell mediated immune responses. • WA increased basal ROS levels in lymphocytes. • WA directly interacted with GSH as studied using spectrophotometry and HPLC. • WA inhibited NF-κB nuclear translocation and binding of nuclear NF-κB to DNA. • WA inhibited induction of the graft-versus-host disease in mice.

Identification of derlin-1 as a novel growth factor-responsive endothelial antigen by suppression subtractive hybridization

International Nuclear Information System (INIS)

Ran Yuliang; Jiang Yangfu; Zhong Xing; Zhou Zhuan; Liu Haiyan; Hu Hai; Lou Jinning; Yang Zhihua

2006-01-01

Endothelial cells play an important regulatory role in embryonic development, reproductive functions, tumor growth and progression. In the present study, the suppression subtractive hybridization (SSH) method was employed to identify differentially expressed genes between non-stimulated endothelial cells and activated endothelial cells. Following mRNA isolation of non-stimulated and hepatocellular carcinoma homogenate-stimulated cells, cDNAs of both populations were prepared and subtracted by suppressive PCR. Sequencing of the enriched cDNAs identified a couple of genes differentially expressed, including derlin-1. Derlin-1 was significantly up-regulated by tumor homogenates, VEGF, and endothelial growth supplements in a dose-dependent manner. Knock-down of derlin-1 triggered endothelial cell apoptosis, inhibited endothelial cell proliferation, and blocked the formation of a network of tubular-like structures. Our data reveal that derlin-1 is a novel growth factor-responsive endothelial antigen that promotes endothelial cell survival and growth

Physiological and biochemical responses of thyme plants to some antioxidants

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SALWA A. ORABI

2014-11-01

Full Text Available Orabi SA, Talaat IM, Balbaa LK. 2014. Physiological and biochemical responses of thyme plants to some antioxidants. Nusantara Bioscience 6: 118-125. Two pot experiments were conducted to investigate the effect of tryptophan, nicotinamide and α-tocopherol (each at 50 and 100 mg/L on plant growth, essential oil yield and its main constituents. All treatments significantly promoted plant height, and increased fresh and dry mass (g/plant of thyme (Thymus vulgaris L.. The treatment with 100 mg/L nicotinamide showed increasing in total potassium mainly in the first cut. Total soluble sugars, oil percentage and oil yield and protein recorded increments with tryptophan treatments. Treatment of Thymus plants with 100 mg/L nicotinamide observed the highest percentage of thymol (67.61%. Oxygenated compounds recorded the highest value with 50 mg/L α-tocopherol treatment, while the maximum non-oxygenated ones resulted from the application of 100 mg/L nicotinamide. All treatments under study significantly affected the activity of oxidoreductase enzymes (POX and PPO. Nicotinamide at the concentration of 100 mg/L recorded the highest increments in APX and GR and the lowest values in oxidoreductase enzyme activities added to the lowest values of lipid peroxidation to enhance the best protection of thyme plants.

An essential role of Nrf2 in American ginseng-mediated anti-oxidative actions in cardiomyocytes.

Science.gov (United States)

Li, Jinqing; Ichikawa, Tomonaga; Jin, Yu; Hofseth, Lorne J; Nagarkatti, Prakash; Nagarkatti, Mitzi; Windust, Anthony; Cui, Taixing

2010-07-20

Ginseng has been used as a folk medicine for thousands of years in Asia, and has become a popular herbal medicine world-wide. Recent studies have revealed that ginseng, including American ginseng, exerts antioxidant effects in the cardiovascular system; however, the underlying mechanisms are not fully understood. Thus, we investigated role of Nrf2, a master transcription factor of endogenous anti-oxidative defense systems, in the regulation of American ginseng-mediated anti-oxidative actions in cardiomyocytes. A standardized crude extract of American ginseng was supplied by the National Research Council of Canada, Institute for National Measurement Standards. H9C2 cells, a rat cardiomyocyte cell line, were exposed to angiotensin II (Ang II) or tumor necrosis factor alpha (TNFalpha) to induce oxidative stress that was examined by measuring formation of reactive oxygen and nitrogen species. Oxidative stress-induced cell death was induced by exogenous addition of hydrogen peroxide (H(2)O(2)). Proteins were measured by Western blot and mRNA expression was determined by quantitative real time PCR. Nrf2-driven transcriptional activity was assessed by antioxidant response element (ARE)-luciferase reporter assay. Direct Nrf2 binding to its target gene promoters was determined by chromatin immunoprecipitation assay. Adenoviral over-expression of Nrf2 shRNA was utilized to knock down Nrf2 in H9C2 cells. Immunochemical staining was applied for Nrf2 expression in the heart. American ginseng induced dramatic increases in Nrf2 protein expression, Nrf2 nuclear translocation, Nrf2 transcriptional activity, direct Nrf2 binding to its target gene promoters, and expression of a group of anti-oxidative genes driven by Nrf2 in H9C2 cells. In addition, American ginseng inhibited Ang II- or TNFalpha-induced free radical formation and H(2)O(2)-induced cell death in H9C2 cells over-expressed with control shRNA but not in the cells over-expressed with Nrf2 shRNA. Finally, oral

Excess boron responsive regulations of antioxidative mechanism at physio-biochemical and molecular levels in Arabidopsis thaliana.

Science.gov (United States)

Kayıhan, Doğa Selin; Kayıhan, Ceyhun; Çiftçi, Yelda Özden

2016-12-01

This work was aimed to evaluate the effect of boron (B) toxicity on oxidative damage level, non-enzymatic antioxidant accumulation such as anthocyanin, flavonoid and proline and expression levels of antioxidant enzymes including superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and glutathione reductase (GR) and their respective activities as well as expression levels of miR398 and miR408 in Arabidopsis thaliana. Plants were germinated and grown on MS medium containing 1 mM B (1B) and 3 mM B (3B) for 14 d. Toxic B led to a decrease of photosynthetic pigments and an increase in accumulation of total soluble and insoluble sugars in accordance with phenotypically viewed chlorosis of seedlings through increasing level of B concentration. Along with these inhibitions, a corresponding increase in contents of flavonoid, anthocyanin and proline occurred that provoked oxidative stress tolerance. 3B caused a remarkable increase in total SOD activity whereas the activities of APX, GR and CAT remained unchanged as verified by expected increase in H 2 O 2 content. In contrast to GR, the coincidence was found between the expressions of SOD and APX genes and their respective activities. 1B induced mir398 expression, whereas 3B did not cause any significant change in expression of mir408 and mir398. Expression levels of GR genes were coordinately regulated with DHAR2 expression. Moreover, the changes in expression level of MDAR2 was in accordance with changes in APX6 expression and total APX activity, indicating fine-tuned regulation of ascorbate-glutathione cycle which might trigger antioxidative responses against B toxicity in Arabidopsis thaliana. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Modified Folin-Ciocalteu antioxidant capacity assay for measuring lipophilic antioxidants.

Science.gov (United States)

Berker, Kadriye Isil; Ozdemir Olgun, F Ayca; Ozyurt, Dilek; Demirata, Birsen; Apak, Resat

2013-05-22

The Folin-Ciocalteu (FC) method of performing a total phenolics assay, originally developed for protein determination, has recently evolved as a total antioxidant capacity assay but was found to be incapable of measuring lipophilic antioxidants due to the high affinity of the FC chromophore, that is, multivalent-charged phospho-tungsto-molybdate(V), toward water. Thus, the FC method was modified and standardized so as to enable simultaneous measurement of lipophilic and hydrophilic antioxidants in NaOH-added isobutanol-water medium. Optimal conditions were as follows: dilution ratio of aqueous FC reagent with iso-BuOH (1:2, v/v), final NaOH concentration of 3.5 × 10(-2) M, reaction time of 20 min, and maximum absorption wavelength of 665 nm. The modified procedure was successfully applied to the total antioxidant capacity assay of trolox, quercetin, ascorbic acid, gallic acid, catechin, caffeic acid, ferulic acid, rosmarinic acid, glutathione, and cysteine, as well as of lipophilic antioxidants such as α-tocopherol (vitamin E), butylated hydroxyanisole, butylated hydroxytoluene, tertiary butylhydroquinone, lauryl gallate, and β-carotene. The modified FC method reliably quantified ascorbic acid, whereas the conventional method could not. The modified method was reproducible and additive in terms of total antioxidant capacity values of constituents of complex mixtures such as olive oil extract and herbal tea infusion. The trolox equivalent antioxidant capacities of the tested antioxidant compounds correlated well with those found by the Cupric Reducing Antioxidant Capacity reference method.

Plant derived antioxidants and antifibrotic drugs: past, present and future

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Devaraj Ezhilarasan

2014-09-01

Full Text Available Hepatic fibrosis occurs as a wound-healing process after several forms of chronic hepatic injury. Activation and proliferation of hepatic stellate cells play pivotal role in the pathogenesis of hepatic fibrosis. Many researchers, from the therapeutic perspective, have focused their attention on searching for novel agents with inhibitory effects on hepatic stellate cells proliferation and activation to prevent hepatic fibrogenesis and a number of plant derived antioxidants have been tested as anti-fibrogenic agents, they generally suppress proliferation and collagen synthesis. Plants remain an imperative source of novel drugs, novel drug leads and new chemical entities. The plant based drug discovery resulted primarily in the development of antioxidant, anti-cancer and other anti-infectious agents and continues to contribute to the new leads in clinical trials. This review summarizes some of those most important plant derived anti-fibrotic drugs and their beneficial effects on experimentally induced hepatic fibrosis in vitro and in vivo. The plant derived antioxidant compounds described herein are curcumin, silymarin, silibinin, baicalein, resveratrol, salvianolic acids, tetrandine, quercetin and berberine. Studies from ours and as demonstrated by pervious workers much information has been accumulated over the past two decades through in vivo and in vitro. In light of those studies, it has been confirmed that plants derived antioxidants, particularly flavanoids, show a significant influence to block hepatic fibrosis regardless of any etiology. This review outlines recent progress in the use of plant derived drugs against experimentally induced liver fibrosis by in vitro and in vivo studies and summarizes the possible mechanisms anti-fibrotic effects of these compounds.

Suppression of TLR4-mediated inflammatory response by macrophage class A scavenger receptor (CD204)

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Ohnishi, Koji; Komohara, Yoshihiro; Fujiwara, Yukio; Takemura, Kenichi [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Lei, XiaoFeng [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Department of Biochemistry, Showa University School of Medicine, Tokyo (Japan); Nakagawa, Takenobu [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Sakashita, Naomi [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Department of Human Pathology, Institute of Health Biosciences, The University of Tokushima, Tokushima (Japan); Takeya, Motohiro, E-mail: takeya@kumamoto-u.ac.jp [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan)

2011-08-05

Highlights: {yields} We focused on the interaction between SR-A and TLR4 signaling in this study. {yields} SR-A deletion promoted NF{kappa}B activation in macrophages in septic model mouse. {yields} SR-A suppresses both MyD88-dependent and -independent TLR4 signaling in vitro. {yields} SR-A clears LPS binding to TLR4 which resulting in the suppression of TLR4 signals. -- Abstract: The class A scavenger receptor (SR-A, CD204), one of the principal receptors expressed on macrophages, has been found to regulate inflammatory response and attenuate septic endotoxemia. However, the detailed mechanism of this process has not yet been well characterized. To clarify the regulative mechanisms of lipopolysaccharide (LPS)-induced macrophage activation by SR-A, we evaluated the activation of Toll-like receptor 4 (TLR4)-mediated signaling molecules in SR-A-deficient (SR-A{sup -/-}) macrophages. In a septic shock model, the blood levels of tumor necrosis factor (TNF)-{alpha}, interleukin (IL)-6 and interferon (IFN)-{beta} were significantly increased in SR-A{sup -/-} mice compared to wild-type mice, and elevated nuclear factor kappa B (NF{kappa}B) activation was detected in SR-A{sup -/-} macrophages. SR-A deletion increased the production of pro-inflammatory cytokines, and the phosphorylation of mitogen-activated protein kinase (MAPK) and NF{kappa}B in vitro. SR-A deletion also promoted the nuclear translocation of NF{kappa}B and IFN regulatory factor (IRF)-3. In addition, a competitive binding assay with acetylated low-density lipoprotein, an SR-A-specific ligand, and anti-SR-A antibody induced significant activation of TLR4-mediated signaling molecules in wild-type macrophages but not in SR-A{sup -/-} macrophages. These results suggest that SR-A suppresses the macrophage activation by inhibiting the binding of LPS to TLR4 in a competitive manner and it plays a pivotal role in the regulation of the LPS-induced inflammatory response.

Antioxidant factors, nitric oxide levels, and cellular damage in leprosy patients

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Taysa Ribeiro Schalcher

2013-09-01

Full Text Available Introduction The immune response caused by Mycobacterium leprae is a risk factor for the development of oxidative stress (OS in leprosy patients. This study aimed to assess OS in leprosy patients before the use of a multidrug therapy. Methods We evaluated the nitric oxide (NO concentration; antioxidant capacity; levels of malondialdehyde, methemoglobin and reduced glutathione; and the activity of catalase and superoxide dismutase (SOD in leprosy patients. Results We observed lower SOD activity in these leprosy patients; however, the NO levels and antioxidant capacity were increased. Conclusions The infectious process in response to M. leprae could primarily be responsible for the OS observed in these patients.

Radiation Therapy Induces Macrophages to Suppress T-Cell Responses Against Pancreatic Tumors in Mice.

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Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Nguy, Susanna; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Daley, Donnele; Barilla, Rocky; Tippens, Daniel; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu R; Hajdu, Cristina; Pellicciotta, Ilenia; Oh, Philmo; Du, Kevin; Miller, George

2016-06-01

The role of radiation therapy in the treatment of patients with pancreatic ductal adenocarcinoma (PDA) is controversial. Randomized controlled trials investigating the efficacy of radiation therapy in patients with locally advanced unresectable PDA have reported mixed results, with effects ranging from modest benefit to worse outcomes compared with control therapies. We investigated whether radiation causes inflammatory cells to acquire an immune-suppressive phenotype that limits the therapeutic effects of radiation on invasive PDAs and accelerates progression of preinvasive foci. We investigated the effects of radiation therapy in p48(Cre);LSL-Kras(G12D) (KC) and p48(Cre);LSLKras(G12D);LSL-Trp53(R172H) (KPC) mice, as well as in C57BL/6 mice with orthotopic tumors grown from FC1242 cells derived from KPC mice. Some mice were given neutralizing antibodies against macrophage colony-stimulating factor 1 (CSF1 or MCSF) or F4/80. Pancreata were exposed to doses of radiation ranging from 2 to 12 Gy and analyzed by flow cytometry. Pancreata of KC mice exposed to radiation had a higher frequency of advanced pancreatic intraepithelial lesions and more foci of invasive cancer than pancreata of unexposed mice (controls); radiation reduced survival time by more than 6 months. A greater proportion of macrophages from radiation treated invasive and preinvasive pancreatic tumors had an immune-suppressive, M2-like phenotype compared with control mice. Pancreata from mice exposed to radiation had fewer CD8(+) T cells than controls, and greater numbers of CD4(+) T cells of T-helper 2 and T-regulatory cell phenotypes. Adoptive transfer of T cells from irradiated PDA to tumors of control mice accelerated tumor growth. Radiation induced production of MCSF by PDA cells. A neutralizing antibody against MCSF prevented radiation from altering the phenotype of macrophages in tumors, increasing the anti-tumor T-cell response and slowing tumor growth. Radiation treatment causes macrophages

Dihydro-CDDO-trifluoroethyl amide suppresses inflammatory responses in macrophages via activation of Nrf2

International Nuclear Information System (INIS)

Li, Bin; Abdalrahman, Akram; Lai, Yimu; Janicki, Joseph S.; Ward, Keith W.; Meyer, Colin J.; Wang, Xing Li; Tang, Dongqi; Cui, Taixing

2014-01-01

Highlights: • Dh404 suppresses the expression of a selected set of pro-inflammatory cytokines in inflamed macrophages via activating Nrf2. • Dh404 activates Nrf2 while keeping Keap1 function intact in macrophages. • Dh404 minimally regulates NF-κB pathway in macrophages. - Abstract: Nuclear factor erythroid 2-related factor (Nrf2) is the major regulator of cellular defenses against various pathological stresses in a variety of organ systems, thus Nrf2 has evolved to be an attractive drug target for the treatment and/or prevention of human disease. Several synthetic oleanolic triterpenoids including dihydro-CDDO-trifluoroethyl amide (dh404) appear to be potent activators of Nrf2 and exhibit chemopreventive promises in multiple disease models. While the pharmacological efficacy of Nrf2 activators may be dependent on the nature of Nrf2 activation in specific cell types of target organs, the precise role of Nrf2 in mediating biological effects of Nrf2 activating compounds in various cell types remains to be further explored. Herein we report a unique and Nrf2-dependent anti-inflammatory profile of dh404 in inflamed macrophages. In lipopolysaccharide (LPS)-inflamed RAW264.7 macrophages, dh404 dramatically suppressed the expression of pro-inflammatory cytokines including inducible nitric oxide synthase (iNOS), monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1 beta (MIP-1β), while minimally regulating the expression of interleulin-6 (IL-6), IL-1β, and tumor necrosis factor alpha (TNFα). Dh404 potently activated Nrf2 signaling; however, it did not affect LPS-induced NF-κB activity. Dh404 did not interrupt the interaction of Nrf2 with its endogenous inhibitor Kelch-like ECH associating protein 1 (Keap1) in macrophages. Moreover, knockout of Nrf2 blocked the dh404-induced anti-inflammatory responses in LPS-inflamed macrophages. These results demonstrated that dh404 suppresses pro-inflammatory responses in macrophages via an activation

Dihydro-CDDO-trifluoroethyl amide suppresses inflammatory responses in macrophages via activation of Nrf2

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Li, Bin [Shandong University Qilu Hospital Research Center for Cell Therapy, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital of Shandong University, Jinan 250012 (China); Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Abdalrahman, Akram; Lai, Yimu; Janicki, Joseph S. [Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Ward, Keith W.; Meyer, Colin J. [Department of Pharmacology, Reata Pharmaceuticals, Inc., Irving, TX 75063 (United States); Wang, Xing Li [Shandong University Qilu Hospital Research Center for Cell Therapy, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital of Shandong University, Jinan 250012 (China); Tang, Dongqi, E-mail: Dongqi.Tang@uscmed.sc.edu [Shandong University Qilu Hospital Research Center for Cell Therapy, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital of Shandong University, Jinan 250012 (China); Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Cui, Taixing, E-mail: taixing.cui@uscmed.sc.edu [Shandong University Qilu Hospital Research Center for Cell Therapy, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital of Shandong University, Jinan 250012 (China); Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208 (United States)

2014-02-21

Highlights: • Dh404 suppresses the expression of a selected set of pro-inflammatory cytokines in inflamed macrophages via activating Nrf2. • Dh404 activates Nrf2 while keeping Keap1 function intact in macrophages. • Dh404 minimally regulates NF-κB pathway in macrophages. - Abstract: Nuclear factor erythroid 2-related factor (Nrf2) is the major regulator of cellular defenses against various pathological stresses in a variety of organ systems, thus Nrf2 has evolved to be an attractive drug target for the treatment and/or prevention of human disease. Several synthetic oleanolic triterpenoids including dihydro-CDDO-trifluoroethyl amide (dh404) appear to be potent activators of Nrf2 and exhibit chemopreventive promises in multiple disease models. While the pharmacological efficacy of Nrf2 activators may be dependent on the nature of Nrf2 activation in specific cell types of target organs, the precise role of Nrf2 in mediating biological effects of Nrf2 activating compounds in various cell types remains to be further explored. Herein we report a unique and Nrf2-dependent anti-inflammatory profile of dh404 in inflamed macrophages. In lipopolysaccharide (LPS)-inflamed RAW264.7 macrophages, dh404 dramatically suppressed the expression of pro-inflammatory cytokines including inducible nitric oxide synthase (iNOS), monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1 beta (MIP-1β), while minimally regulating the expression of interleulin-6 (IL-6), IL-1β, and tumor necrosis factor alpha (TNFα). Dh404 potently activated Nrf2 signaling; however, it did not affect LPS-induced NF-κB activity. Dh404 did not interrupt the interaction of Nrf2 with its endogenous inhibitor Kelch-like ECH associating protein 1 (Keap1) in macrophages. Moreover, knockout of Nrf2 blocked the dh404-induced anti-inflammatory responses in LPS-inflamed macrophages. These results demonstrated that dh404 suppresses pro-inflammatory responses in macrophages via an activation

Flavonoids Extraction from Taraxacum officinale (Dandelion: Optimisation Using Response Surface Methodology and Antioxidant Activity

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Zongxi Sun

2014-01-01

Full Text Available The Box-Behnken design combined with response surface method was employed to optimize ultrasonic-assisted extraction of flavonoids from Taraxacum officinale. The optimized results showed that the highest extraction yield with ultrasonic-assisted extraction could reach 2.62% using 39.6% (v/v ethanol and 59.5 : 1 (mL/g liquid-solid ratio for 43.8 min. The crude extract was then purified by HPD-100 macroporous adsorption resin, and the flavonoids content in the purified extract increased to 54.7%. The antioxidant activity of the purified flavonoids was evaluated in vitro by scavenging capacity of ABTS or DPPH, β-carotene bleaching, and FTC test. The knowledge obtained from this study should be useful to further develop and apply this plant resource.

Suppression of the E. coli SOS response by dNTP pool changes.

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Maslowska, Katarzyna H; Makiela-Dzbenska, Karolina; Fijalkowska, Iwona J; Schaaper, Roel M

2015-04-30

The Escherichia coli SOS system is a well-established model for the cellular response to DNA damage. Control of SOS depends largely on the RecA protein. When RecA is activated by single-stranded DNA in the presence of a nucleotide triphosphate cofactor, it mediates cleavage of the LexA repressor, leading to expression of the 30(+)-member SOS regulon. RecA activation generally requires the introduction of DNA damage. However, certain recA mutants, like recA730, bypass this requirement and display constitutive SOS expression as well as a spontaneous (SOS) mutator effect. Presently, we investigated the possible interaction between SOS and the cellular deoxynucleoside triphosphate (dNTP) pools. We found that dNTP pool changes caused by deficiencies in the ndk or dcd genes, encoding nucleoside diphosphate kinase and dCTP deaminase, respectively, had a strongly suppressive effect on constitutive SOS expression in recA730 strains. The suppression of the recA730 mutator effect was alleviated in a lexA-deficient background. Overall, the findings suggest a model in which the dNTP alterations in the ndk and dcd strains interfere with the activation of RecA, thereby preventing LexA cleavage and SOS induction. Published by Oxford University Press on behalf of Nucleic Acids Research 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Sulforaphane Suppresses Hepatitis C Virus Replication by Up-Regulating Heme Oxygenase-1 Expression through PI3K/Nrf2 Pathway.

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Jung-Sheng Yu

Full Text Available Hepatitis C virus (HCV infection-induced oxidative stress is a major risk factor for the development of HCV-associated liver disease. Sulforaphane (SFN is an antioxidant phytocompound that acts against cellular oxidative stress and tumorigenesis. However, there is little known about its anti-viral activity. In this study, we demonstrated that SFN significantly suppressed HCV protein and RNA levels in HCV replicon cells and infectious system, with an IC50 value of 5.7 ± 0.2 μM. Moreover, combination of SFN with anti-viral drugs displayed synergistic effects in the suppression of HCV replication. In addition, we found nuclear factor erythroid 2-related factor 2 (Nrf2/HO-1 induction in response to SFN and determined the signaling pathways involved in this process, including inhibition of NS3 protease activity and induction of IFN response. In contrast, the anti-viral activities were attenuated by knockdown of HO-1 with specific inhibitor (SnPP and shRNA, suggesting that anti-HCV activity of SFN is dependent on HO-1 expression. Otherwise, SFN stimulated the phosphorylation of phosphoinositide 3-kinase (PI3K leading Nrf2-mediated HO-1 expression against HCV replication. Overall, our results indicated that HO-1 is essential in SFN-mediated anti-HCV activity and provide new insights in the molecular mechanism of SFN in HCV replication.

Effect of dietary carbohydrate on non-specific immune response, hepatic antioxidative abilities and disease resistance of juvenile golden pompano (Trachinotus ovatus).

Science.gov (United States)

Zhou, Chuanpeng; Ge, Xianping; Lin, Heizhao; Niu, Jin

2014-12-01

The present study was conducted to investigate the effects of dietary carbohydrate (CHO) levels on non-specific immune responses, hepatic antioxidative status and disease resistance of juvenile golden pompano. Fish were fed six isonitrogenous and isoenergetic diets containing various CHO levels for 8 weeks. After the feeding trial, fish were challenged by Vibrio harveyi and survival rate was recorded for the next 12 days. Plasma total protein and albumin content, respiratory burst activity, alkaline phosphatase, slightly increased with dietary starch level from 0% to 16.8%, but significantly decreased at dietary starch levels of 16.8%-28%. Plasma lysozyme, complement 3 and complement 4 levels increased with increasing dietary carbohydrate up to 11.2% and then declined (P 0.05) with those of the other treatments. After challenge, fish fed 11.2% and 16.8% dietary CHO showed higher survival rate than that of fish in 0% CHO group (P 0.05). The results of this study suggest that ingestion of 11.2-16.8% dietary CHO can enhance the non-specific immune responses, increase the hepatic antioxidant abilities, and improve resistance to V. harveyi infection of juvenile golden pompano. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synthesis and DPPH scavenging assay of reserpine analogues, computational studies and in silico docking studies in AChE and BChE responsible for Alzheimer's disease

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Muhammad Yar

2015-03-01

Full Text Available Alzheimer's disease (AD is a fast growing neurodegenerative disorder of the central nervous system and anti-oxidants can be used to help suppress the oxidative stress caused by the free radicals that are responsible for AD. A series of selected synthetic indole derivatives were biologically evaluated to identify potent new antioxidants. Most of the evaluated compounds showed significant to modest antioxidant properties (IC50 value 399.07 140.0±50 µM. Density Functional Theory (DFT studies were carried out on the compounds and their corresponding free radicals. Differences in the energy of the parent compounds and their corresponding free radicals provided a good justification for the trend found in their IC50 values. In silico, docking of compounds into the proteins acetylcholinesterase (AChE and butyrylcholinesterase (BChE, which are well known for contributing in AD disease, was also performed to predict anti-AD potential.

Suppression of the primary immune response in rainbow trout, Salmo gairdneri, sublethally exposed to tritiated water during embryogenesis

International Nuclear Information System (INIS)

Strand, J.A.

1975-01-01

Antibody synthesis in response to vaccination with a 0.1 cc (1.8 x 10 8 cells/cc) intraperitoneally injected heat-killed strain of Flexibacter columnaris was employed to investigate the effect of tritium irradiation (0, 0.04, 0.4, 4.0 and 40.0 rads total dose for 20 days during embryogenesis) on development of the primary immune response in 5-month rainbow trout, Salmo gairdneri. Total serum protein measurements and electrophoretic separation of blood serum proteins followed by densitometric analyses were performed to assess the potential for qualitative and quantitative changes in blood serum components which conceivably accounted for suppressed immune responsiveness in tritium-irradiated fish. Data on the biological effects of tritium on early life stages in terms of hatchability, abnormality, latent mortality, and growth were also collected. A review of all experiments directed at determining the effects of early radiation exposure on the parameters of hatchability, incidence of abnormality, latent mortality and depressed growth, revealed considerable variation among similar treatments and indicated that significant effects at dose levels of 50 rads and below were not consistently demonstrated. While present experimental results demonstrated that the primary immune response in juvenile rainbow trout was significantly suppressed following embryonic exposure to tritium at essentially the 1.0 μCi/ml level, and perhaps at the 0.1 μCi/ml level, these concentrations are no less than 5 to 6 orders of magnitude above present levels for tritium in the aquatic environment

Optimization of antioxidant phenolic compounds extraction from quinoa (Chenopodium quinoa) seeds.

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Carciochi, Ramiro Ariel; Manrique, Guillermo Daniel; Dimitrov, Krasimir

2015-07-01

The objective of this study was to optimize the extraction conditions of phenolic and flavonoids compounds from quinoa (Chenopodium quinoa) seeds using ultrasound assistance technology. A randomized central composite face-centered design was used to evaluate the effect of extraction temperature, ethanol concentration in the solvent, and ultrasound power on the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity by response surface analysis. Predicted model equations were obtained to describe the experimental data regarding TPC, TFC and antioxidant activity, with significant variation in the linear, quadratic, and interaction effects of the independent variables. Regression analysis showed that more than 88 % of the variability was explained by the models. The best extraction conditions obtained by simultaneous maximization of the responses were: extraction temperature of 60 °C, 80 % ethanol as solvent and non-application of ultrasounds. Under the optimal conditions, the corresponding predicted response values were 103.6 mg GAE/100 g dry weight (dw), 25.0 mg quercetin equiv./100 g dw and 28.6 % DPPH radical scavenging, for TPC, TFC and antioxidant activity, respectively. The experimental values agreed with those predicted within a 95 % confidence level, indicating the suitability of the employed model. HPLC analysis of the obtained extracts confirmed the highest phenolic compound yield in the extract obtained under optimal extraction conditions. Considering the characteristics of the antioxidant-rich extracts obtained, they could be consider for potential application in the food industry, as nutraceutical and functional foods ingredient or well as replacement of synthetic antioxidants.

Effects of salicylic acid on monoterpene production and antioxidant ...

African Journals Online (AJOL)

Salicylic acid (SA) plays important roles in plant defense responses. However, little is available about its effects on monoterpene responses. Therefore, monoterpene contents and antioxidant systems were measured three days after foliar application of SA with different concentrations in Houttuynia cordata. SA at low ...

An aryl hydrocarbon receptor ligand acts on dendritic cells and T cells to suppress the Th17 response in allergic rhinitis patients.

Science.gov (United States)

Wei, Ping; Hu, Guo-Hua; Kang, Hou-Yong; Yao, Hong-Bing; Kou, Wei; Liu, Hong; Zhang, Cheng; Hong, Su-Ling

2014-05-01

A predominant Th17 population is a marker of allergic rhinitis (AR). The aryl hydrocarbon receptor (AhR) exhibits strong immunomodulation potential via regulation of the differentiation of T lymphocytes and dendritic cells (DCs) after activation by its ligand, such as 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE). The aim of this study was to analyze the effect of AhR on Th17 differentiation by investigating the action of ITE on DCs and CD4(+) T cells from patients with AR. In all, 26 AR patients and 12 healthy controls were included in this study. The expression of interleukin (IL)-1β, IL-6, IL-10, and IL-17 in the culture supernatant and the presence of Th17 cells in CD4(+) T cells and DC-CD4(+) T-cell co-culture system were measured before and after treatment with ITE. We show that ITE significantly induced cell secretion of IL-10 and inhibited IL-1β and IL-6 production in DCs, and promoted IL-10 production and suppressed IL-17 expression in CD4(+) T cells in vitro. It also suppressed the expansion of Th17 cells in vitro. Our work demonstrates that ITE acts on DCs and CD4(+) T cells to inhibit the Th17 response that suppresses AR; the AhR-DC-Th17 axis may be an important pathway in the treatment of AR. ITE, a nontoxic AhR ligand, attenuated the Th17 response; thus, it appears to be a promising therapeutic candidate for suppressing the inflammatory responses associated with AR.

Mechanism Profiling of Hepatotoxicity Caused by Oxidative Stress Using Antioxidant Response Element Reporter Gene Assay Models and Big Data.

Science.gov (United States)

Kim, Marlene Thai; Huang, Ruili; Sedykh, Alexander; Wang, Wenyi; Xia, Menghang; Zhu, Hao

2016-05-01

Hepatotoxicity accounts for a substantial number of drugs being withdrawn from the market. Using traditional animal models to detect hepatotoxicity is expensive and time-consuming. Alternative in vitro methods, in particular cell-based high-throughput screening (HTS) studies, have provided the research community with a large amount of data from toxicity assays. Among the various assays used to screen potential toxicants is the antioxidant response element beta lactamase reporter gene assay (ARE-bla), which identifies chemicals that have the potential to induce oxidative stress and was used to test > 10,000 compounds from the Tox21 program. The ARE-bla computational model and HTS data from a big data source (PubChem) were used to profile environmental and pharmaceutical compounds with hepatotoxicity data. Quantitative structure-activity relationship (QSAR) models were developed based on ARE-bla data. The models predicted the potential oxidative stress response for known liver toxicants when no ARE-bla data were available. Liver toxicants were used as probe compounds to search PubChem Bioassay and generate a response profile, which contained thousands of bioassays (> 10 million data points). By ranking the in vitro-in vivo correlations (IVIVCs), the most relevant bioassay(s) related to hepatotoxicity were identified. The liver toxicants profile contained the ARE-bla and relevant PubChem assays. Potential toxicophores for well-known toxicants were created by identifying chemical features that existed only in compounds with high IVIVCs. Profiling chemical IVIVCs created an opportunity to fully explore the source-to-outcome continuum of modern experimental toxicology using cheminformatics approaches and big data sources. Kim MT, Huang R, Sedykh A, Wang W, Xia M, Zhu H. 2016. Mechanism profiling of hepatotoxicity caused by oxidative stress using antioxidant response element reporter gene assay models and big data. Environ Health Perspect 124:634-641;�

Anti-oxidative effects of Rooibos tea (Aspalathus linearis on immobilization-induced oxidative stress in rat brain.

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In-Sun Hong

Full Text Available Exposure to chronic psychological stress may be related to increased reactive oxygen species (ROS or free radicals, and thus, long-term exposure to high levels of oxidative stress may cause the accumulation of oxidative damage and eventually lead to many neurodegenerative diseases. Compared with other organs, the brain appears especially susceptible to excessive oxidative stress due to its high demand for oxygen. In the case of excessive ROS production, endogenous defense mechanisms against ROS may not be sufficient to suppress ROS-associated oxidative damage. Dietary antioxidants have been shown to protect neurons against a variety of experimental neurodegenerative conditions. In particular, Rooibos tea might be a good source of antioxidants due to its larger proportion of polyphenolic compounds. An optimal animal model for stress should show the features of a stress response and should be able to mimic natural stress progression. However, most animal models of stress, such as cold-restraint, electric foot shock, and burn shock, usually involve physical abuse in addition to the psychological aspects of stress. Animals subjected to chronic restraint or immobilization are widely believed to be a convenient and reliable model to mimic psychological stress. Therefore, in the present study, we propose that immobilization-induced oxidative stress was significantly attenuated by treatment with Rooibos tea. This conclusion is demonstrated by Rooibos tea's ability to (i reverse the increase in stress-related metabolites (5-HIAA and FFA, (ii prevent lipid peroxidation (LPO, (iii restore stress-induced protein degradation (PD, (iv regulate glutathione metabolism (GSH and GSH/GSSG ratio, and (v modulate changes in the activities of antioxidant enzymes (SOD and CAT.

A hydrophobic anchor mechanism defines a deacetylase family that suppresses host response against YopJ effectors.

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Bürger, Marco; Willige, Björn C; Chory, Joanne

2017-12-19

Several Pseudomonas and Xanthomonas species are plant pathogens that infect the model organism Arabidopsis thaliana and important crops such as Brassica. Resistant plants contain the infection by rapid cell death of the infected area through the hypersensitive response (HR). A family of highly related α/β hydrolases is involved in diverse processes in all domains of life. Functional details of their catalytic machinery, however, remained unclear. We report the crystal structures of α/β hydrolases representing two different clades of the family, including the protein SOBER1, which suppresses AvrBsT-incited HR in Arabidopsis. Our results reveal a unique hydrophobic anchor mechanism that defines a previously unknown family of protein deacetylases. Furthermore, this study identifies a lid-loop as general feature for substrate turnover in acyl-protein thioesterases and the described family of deacetylases. Furthermore, we found that SOBER1's biological function is not restricted to Arabidopsis thaliana and not limited to suppress HR induced by AvrBsT.

Evaluation of the antioxidant properties of N-acetylcysteine in human platelets: prerequisite for bioconversion to glutathione for antioxidant and antiplatelet activity.

Science.gov (United States)

Gibson, Kyle R; Neilson, Ilene L; Barrett, Fiona; Winterburn, Tim J; Sharma, Sushma; MacRury, Sandra M; Megson, Ian L

2009-10-01

N-Acetylcysteine (NAC) is a frequently used "antioxidant" in vitro, but the concentrations applied rarely correlate with those encountered with oral dosing in vivo. Here, we investigated the in vitro antioxidant and antiplatelet properties of NAC at concentrations (10-100 microM) that are achievable in plasma with tolerable oral dosing. The impact of NAC pretreatment (2 hours) on aggregation of platelets from healthy volunteers in response to thrombin and adenosine diphosphate and on platelet-derived nitric oxide (NO) was examined. NAC was found to be a weak reducing agent and a poor antioxidant compared with glutathione (reduced form) (GSH). However, platelets treated with NAC showed enhanced antioxidant activity and depression of reactive oxygen species generation associated with increases in intraplatelet GSH levels. An approximately 2-fold increase in NO synthase-derived nitrite was observed with 10 microM NAC treatment, but the effect was not concentration dependent. Finally, NAC significantly reduced both thrombin-induced and adenosine diphosphate-induced platelet aggregation. NAC should be considered a weak antioxidant that requires prior conversion to GSH to convey antioxidant and antithrombotic benefit at therapeutically relevant concentrations. Our results suggest that NAC might be an effective antiplatelet agent in conditions where increased oxidative stress contributes to heightened risk of thrombosis but only if the intraplatelet machinery to convert it to GSH is functional.

Unraveling the mechanism responsible for the contrasting tolerance of Synechocystis and Synechococcus to Cr(VI): Enzymatic and non-enzymatic antioxidants

Energy Technology Data Exchange (ETDEWEB)

Gupta, Alka [Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Ballal, Anand, E-mail: aballal@barc.gov.in [Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 40085 (India)

2015-07-15

Highlights: • Cr(VI) accumulation generates higher ROS in Synechocystis than in Synechococcus. • Synechococcus exhibits better photosynthetic activity in response to Cr(VI). • Synechococcus has higher enzymatic/non-enzymatic antioxidants than Synechocystis. • Synechococcus shows better tolerance to other oxidative stresses than Synechocystis. • Differential detoxification of ROS is responsible for the contrasting tolerance to Cr(VI) - Abstract: Two unicellular cyanobacteria, Synechocystis and Synechococcus, showed contrasting tolerance to Cr(VI); with Synechococcus being 12-fold more tolerant than Synechocystis to potassium dichromate. The mechanism responsible for this differential sensitivity to Cr(VI) was explored in this study. Total content of photosynthetic pigments as well as photosynthetic activity decreased at lower concentration of Cr(VI) in Synechocystis as compared to Synechococcus. Experiments with {sup 51}Cr showed Cr to accumulate intracellularly in both the cyanobacteria. At lower concentrations, Cr(VI) caused excessive ROS generation in Synechocystis as compared to that observed in Synechococcus. Intrinsic levels of enzymatic antioxidants, i.e., superoxide dismutase, catalase and 2-Cys-peroxiredoxin were considerably higher in Synechococcus than Synechocystis. Content of total thiols (both protein as well as non-protein) and reduced glutathione (GSH) was also higher in Synechococcus as compared to Synechocystis. This correlated well with higher content of carbonylated proteins observed in Synechocystis than Synechococcus. Additionally, in contrast to Synechocystis, Synechococcus exhibited better tolerance to other oxidative stresses like high intensity light and H{sub 2}O{sub 2}. The data indicate that the disparity in the ability to detoxify ROS could be the primary mechanism responsible for the differential tolerance of these cyanobacteria to Cr(VI)

Anti-inflammatory compound resveratrol suppresses homocysteine formation in stimulated human peripheral blood mononuclear cells in vitro.

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Schroecksnadel, Katharina; Winkler, Christiana; Wirleitner, Barbara; Schennach, Harald; Weiss, Günter; Fuchs, Dietmar

2005-01-01

Inflammation, immune activation and oxidative stress play a major role in the pathogenesis of cardiovascular disorders. In addition to markers of inflammation, moderate hyperhomocysteinemia is an independent risk factor for cardiovascular disease, and there is a link between the activation of immunocompetent cells and the enhanced formation of homocysteine in vitro. Likewise, anti-inflammatory drugs and nutrients rich in antioxidant vitamins are able to reduce cardiovascular risk and to slow down the atherogenic process. Resveratrol, a phenolic antioxidant synthesized in grapes and vegetables and present in wine, has also been supposed to be beneficial for the prevention of cardiovascular events. Apart from its strong antioxidant properties, resveratrol has also been demonstrated to act as an anti-inflammatory agent. In this study the influence of resveratrol on the production of homocysteine by stimulated human peripheral blood mononuclear cells (PBMCs) was investigated. Results were compared to earlier described effects of the anti-inflammatory compounds aspirin and salicylic acid and of the lipid-lowering drug atorvastatin. Stimulation of PBMCs with the mitogens concanavalin A and phytohemagglutinin induced significantly higher homocysteine accumulation in supernatants compared with unstimulated cells. Treatment with 10-100 muM resveratrol suppressed homocysteine formation in a dose-dependent manner. Resveratrol did not influence the release of homocysteine from resting PBMCs. The data suggest that resveratrol may prevent homocysteine accumulation in the blood by suppressing immune activation cascades and the proliferation of mitogen-driven T-cells. The effect of resveratrol to down-regulate the release of homo-cysteine was comparable to the decline of neopterin concentrations in the same experiments. The suppressive effect of resveratrol was very similar to results obtained earlier with aspirin, salicylic acid and atorvastatin; however, it appeared that doses

A comparative study on oxidative stress response in the hepatopancreas and midgut of the white shrimp Litopenaeus vannamei under gradual changes to low or high pH environment.

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Han, Si-Yin; Wang, Meng-Qiang; Wang, Bao-Jie; Liu, Mei; Jiang, Ke-Yong; Wang, Lei

2018-05-01

White shrimp Litopenaeus vannamei were reared under conditions of gradual changes to a low pH (gradual-low pH, 6.65-8.20) or a high pH (gradual-high pH, 8.20-9.81) versus a normal pH environment (8.14-8.31) during a 28-day period. Survival of shrimp, and ROS production, antioxidant responses and oxidative damage in the hepatopancreas and midgut were investigated. Consequently, shrimp enhanced MnSOD, GPx, and Hsp70 transcripts as early defense mechanism in the hepatopancreas and midgut to scavenge excessive ROS during short-term (≤ 7 days) gradual-low and high pH stress. Meanwhile, the hepatopancreas was more sensitive to ROS than midgut because of earlier ROS production increase, antioxidant response and oxidative damage. Then, suppressed antioxidant response in the hepatopancreas and midgut of shrimp suggested a loss of antioxidant regulatory capacity caused by aggravated oxidative damage after long-term (≥ 14 days) gradual-high pH stress, leading to continuous death. However, enhanced GPx, GST, and Hsp70 transcripts in the hepatopancreas and midgut might be long-term(≥ 14 days) antioxidant adaptation mechanism of shrimp to gradual-low pH stress, which could prevent further ROS perturbation and weaken oxidative damage to achieve a new immune homeostasis, contributing to stable survival rate. Therefore, we have a few insights that it is necessary to protect hepatopancreas for controlling shrimp death under gradual-high pH stress. Copyright © 2018 Elsevier Ltd. All rights reserved.

Glutathione aerosol suppresses lung epithelial surface inflammatory cell-derived oxidants in cystic fibrosis.

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Roum, J H; Borok, Z; McElvaney, N G; Grimes, G J; Bokser, A D; Buhl, R; Crystal, R G

1999-07-01

Cystic fibrosis (CF) is characterized by accumulation of activated neutrophils and macrophages on the respiratory epithelial surface (RES); these cells release toxic oxidants, which contribute to the marked epithelial derangements seen in CF. These deleterious consequences are magnified, since reduced glutathione (GSH), an antioxidant present in high concentrations in normal respiratory epithelial lining fluid (ELF), is deficient in CF ELF. To evaluate the feasibility of increasing ELF GSH levels and enhancing RES antioxidant protection, GSH aerosol was delivered (600 mg twice daily for 3 days) to seven patients with CF. ELF total, reduced, and oxidized GSH increased (P < 0.05, all compared with before GSH therapy), suggesting adequate RES delivery and utilization of GSH. Phorbol 12-myristate 13-acetate-stimulated superoxide anion (O2-.) release by ELF inflammatory cells decreased after GSH therapy (P < 0.002). This paralleled observations that GSH added in vitro to CF ELF inflammatory cells suppressed O2-. release (P < 0.001). No adverse effects were noted during treatment. Together, these observations demonstrate the feasibility of using GSH aerosol to restore RES oxidant-antioxidant balance in CF and support the rationale for further clinical evaluation.

Effects of dietary fructooligosaccharide levels and feeding modes on growth, immune responses, antioxidant capability and disease resistance of blunt snout bream (Megalobrama amblycephala).

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Zhang, Chun-Nuan; Li, Xiang-Fei; Jiang, Guang-Zhen; Zhang, Ding-Dong; Tian, Hong-Yan; Li, Jun-Yi; Liu, Wen-Bin

2014-12-01

This study aimed to determine the effects of fructooligosaccharide (FOS) levels and its feeding modes on growth, immune response, antioxidant capability and disease resistance of blunt snout bream (Megalobrama amblycephala). Fish (12.5 ± 0.5 g) were subjected to three FOS levels (0, 0.4% and 0.8%) and two feeding modes (supplementing FOS continuously and supplementing FOS two days interval 5 days) according to a 3 × 2 factorial design. At the end of 8-week feeding trial, fish were challenged by Aeromonas hydrophila with concentration of 1 × 10(5) CFU mL(-1) and mortality was recorded for the next 96 h. Fish fed 0.4% FOS continuously (D2) and fish fed the basal diet for 5 days followed by 0.8% FOS for 2 days (D5) showed admirable growth performance. The highest plasma lysozyme, acid phosphatase and myeloperoxidase activities as well as complement component 3, total protein and immunoglobulin M (IgM) levels were all observed in fish fed D5. They were significantly higher (P 0.05) with that of fish fed D2. A similar trend was also observed in antioxidant capability as well as the expression of Leap-I and Leap-Ⅱ. Mortality showed an opposite trend with the immune response with the lowest rate observed in fish fed D5. The results indicated that diet supplementing FOS in appropriate levels and feeding modes could improve the growth, immune response and antioxidant capability of fish, as might consequently lead to enhanced disease resistance. It can be speculated that the basal diet for 5 days followed by 0.8% FOS for 2 days was most suitable for blunt snout bream. Copyright © 2014 Elsevier Ltd. All rights reserved.

Suppression of External NADPH Dehydrogenase—NDB1 in Arabidopsis thaliana Confers Improved Tolerance to Ammonium Toxicity via Efficient Glutathione/Redox Metabolism

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Podgórska, Anna; Borysiuk, Klaudia; Tarnowska, Agata; Jakubiak, Monika; Burian, Maria; Rasmusson, Allan G.

2018-01-01

Environmental stresses, including ammonium (NH4+) nourishment, can damage key mitochondrial components through the production of surplus reactive oxygen species (ROS) in the mitochondrial electron transport chain. However, alternative electron pathways are significant for efficient reductant dissipation in mitochondria during ammonium nutrition. The aim of this study was to define the role of external NADPH-dehydrogenase (NDB1) during oxidative metabolism of NH4+-fed plants. Most plant species grown with NH4+ as the sole nitrogen source experience a condition known as “ammonium toxicity syndrome”. Surprisingly, transgenic Arabidopsis thaliana plants suppressing NDB1 were more resistant to NH4+ treatment. The NDB1 knock-down line was characterized by milder oxidative stress symptoms in plant tissues when supplied with NH4+. Mitochondrial ROS accumulation, in particular, was attenuated in the NDB1 knock-down plants during NH4+ treatment. Enhanced antioxidant defense, primarily concerning the glutathione pool, may prevent ROS accumulation in NH4+-grown NDB1-suppressing plants. We found that induction of glutathione peroxidase-like enzymes and peroxiredoxins in the NDB1-surpressing line contributed to lower ammonium-toxicity stress. The major conclusion of this study was that NDB1 suppression in plants confers tolerance to changes in redox homeostasis that occur in response to prolonged ammonium nutrition, causing cross tolerance among plants. PMID:29747392

Organoleptic quality and antioxidant status of radiation processed food commodities

International Nuclear Information System (INIS)

Chatterjee, S.; Sharma, J.; Arul, A.K.; Variyar, P.S.; Sharma, A.

2009-01-01

Effect of radiation processing on the organoleptic qualities such as aroma, taste and colour as well as antioxidant status of various food classes such as beverages (monsooned coffee), spices (nutmeg), fruits (pomegranate), oil seeds (soybean) and vegetables (guar beans) was investigated. The factors responsible for these attributes were shown to be liberated from their glycosidic precursors during radiation processing, thus resulted in an enhancement of organoleptic quality and antioxidant status. (author)

SERPINA3K plays antioxidant roles in cultured pterygial epithelial cells through regulating ROS system.

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Chengpeng Zhu

Full Text Available We recently demonstrated that SERPINA3K, a serine proteinase inhibitor, has antioxidant activity in the cornea. Here we investigated the antioxidant effects of SERPINA3K on the pterygial, which is partially caused by oxidative stress in pathogenesis. The head part of primary pterygial tissue was dissected and then cultured in keratinocyte serum-free defined medium (KSFM. The cultured pterygial epithelial cells (PECs were treated with SERPINA3K. The cell proliferation and migration of PECs were measured and analyzed. Western blot and quantitative real-time polymerase chain reaction (PCR assay were performed. It showed that SERPINA3K significantly suppressed the cell proliferation of PECs in a concentration-dependent manner, compared with cultured human conjunctival epithelial cells. SERPINA3K also inhibited the cell migration of PECs. Towards its underlying mechanism, SERPINA3K had antioxidant activities on the PECs by significantly inhibiting NADPH oxidase 4 (NOX4, which is an important enzyme of ROS generation, and by elevating the levels of key antioxidant factors of ROS: such as NAD(PH dehydrogenase (quinone 1 (NQO1, NF-E2-related factor-2 (NRF2 and superoxide dismutases (SOD2. Meanwhile, SERPINA3K down-regulated the key effectors of Wnt signaling pathway: β-catenin, nonphospho-β-catenin, and low-density lipoprotein receptor-related protein 6 (LRP6. We provided novel evidence that SERPINA3K had inhibitory effects on pterygium and SERPINA3K played antioxidant role via regulating the ROS system and antioxidants.

A novel procedure for the assessment of the antioxidant capacity of food components.

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Yoshimura, Toshihiro; Harashima, Mai; Kurogi, Katsuhisa; Suiko, Masahito; Liu, Ming-Cheh; Sakakibara, Yoichi

2016-08-15