TY - JOUR A1 - Plauth, Annabell A1 - Geikowski, Anne A1 - Cichon, Susanne A1 - Wowro, Sylvia J. A1 - Liedgens, Linda A1 - Rousseau, Morten A1 - Weidner, Christopher A1 - Fuhr, Luise A1 - Kliem, Magdalena A1 - Jenkins, Gail A1 - Lotito, Silvina A1 - Wainwright, Linda J. A1 - Sauer, Sascha T1 - Hormetic shifting of redox environment by pro-oxidative resveratrol protects cells against stress JF - Free Radical Biology and Medicine N2 - Resveratrol has gained tremendous interest owing to multiple reported health-beneficial effects. However, the underlying key mechanism of action of this natural product remained largely controversial. Here, we demonstrate that under physiologically relevant conditions major biological effects of resveratrol can be attributed to its generation of oxidation products such as reactive oxygen species (ROS). At low nontoxic concentrations (in general < 50 mu M), treatment with resveratrol increased viability in a set of representative cell models, whereas application of quenchers of ROS completely truncated these beneficial effects. Notably, resveratrol treatment led to mild, Nrf2-specific gene expression reprogramming. For example, in primary epidermal keratinocytes derived from human skin this coordinated process resulted in a 1.3-fold increase of endogenously generated glutathione (GSH) and subsequently in a quantitative reduction of the cellular redox environment by 2.61 mV mmol GSH per g protein. After induction of oxidative stress by using 0.78% (v/v) ethanol, endogenous generation of ROS was consequently reduced by 24% in resveratrol pre-treated cells. In contrast to the common perception that resveratrol acts mainly as a chemical antioxidant or as a target protein-specific ligand, we propose that the cellular response to resveratrol treatment is essentially based on oxidative triggering. In physiological microenvironments this molecular training can lead to hormetic shifting of cellular defense towards a more reductive state to improve physiological resilience to oxidative stress. KW - Trans-reservatrol KW - Hydrogen-peroxide KW - In-vitro KW - Hormesis KW - Ethanol KW - Oxygen KW - Nrf2 KW - Glutathione KW - Metabolism KW - Polyphenols KW - ROS KW - Oxidative stress KW - Redox environment KW - Skin KW - Epidermis Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187186 VL - 99 ER - TY - JOUR A1 - Schupp, Nicole A1 - Ali, Badreldin H. A1 - Beegam, Sumyia A1 - Al-Husseni, Isehaq A1 - Al-Shukaili, Ahmed A1 - Nemmar, Abderrahim A1 - Schierling, Simone A1 - Queisser, Nina T1 - Effect of gum arabic on oxidative stress and inflammation in adenine-induced chronic renal failure in rats JF - PLoS One N2 - Inflammation and oxidative stress are known to be involved in the pathogenesis of chronic kidney disease in humans, and in chronic renal failure (CRF) in rats. The aim of this work was to study the role of inflammation and oxidative stress in adenine-induced CRF and the effect thereon of the purported nephroprotective agent gum arabic (GA). Rats were divided into four groups and treated for 4 weeks as follows: control, adenine in feed (0.75%, w/w), GA in drinking water (15%, w/v) and adenine+GA, as before. Urine, blood and kidneys were collected from the rats at the end of the treatment for analysis of conventional renal function tests (plasma creatinine and urea concentration). In addition, the concentrations of the pro-inflammatory cytokine TNF-a and the oxidative stress markers glutathione and superoxide dismutase, renal apoptosis, superoxide formation and DNA double strand break frequency, detected by immunohistochemistry for c-H2AX, were measured. Adenine significantly increased the concentrations of urea and creatinine in plasma, significantly decreased the creatinine clearance and induced significant increases in the concentration of the measured inflammatory mediators. Further, it caused oxidative stress and DNA damage. Treatment with GA significantly ameliorated these actions. The mechanism of the reported salutary effect of GA in adenine-induced CRF is associated with mitigation of the adenine-induced inflammation and generation of free radicals. KW - adenine KW - blood plasma KW - creatinine KW - inflammation KW - inflammatory diseases KW - Kidneys KW - Oxidative stress KW - Water resources Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-95787 ER -