Grape seed and skin extract protects kidney from doxorubicin-induced oxidative injury.

The study investigated the protective effect of grape seed and skin extract (GSSE) against doxorubicin-induced renal toxicity in healthy rats. Animals were treated with GSSE or not (control), for 8 days, administered with doxorubicin (20mg/kg) in the 4th day, and renal function as well as oxidative stress parameters were evaluated. Data showed that doxorubicin induced renal toxicity by affecting renal architecture and plasma creatinine. Doxorubicin also induced an oxidative stress characterized by an increase in malondialdehyde (MDA), calcium and H(2)O(2) and a decrease in catalase (CAT) and superoxide dismutase (SOD). Unexpectedly doxorubicin increased peroxidase (POD) and decreased carbonyl protein and plasma urea. Treatment with GSSE counteracted almost all adverse effects induced by doxorubicin. Data suggest that doxorubicin induced an oxidative stress into rat kidney and GSSE exerted antioxidant properties, which seem to be mediated by the modulation of intracellular calcium.

Efficacy of grape seed and skin extract against doxorubicin-induced oxidative stress in rat liver.

Doxorubicin (Dox) is an anthracycline used in chemotherapy, although it causes toxicity and oxidative stress. Grape seed and skin extract (GSSE) is a mixture of polyphenolic compounds with antioxidant properties. To evaluate the hepato-toxicity of Dox on healthy rats as well as the protective effect of GSSE, rats were treated with GSSE (500mg/kg bw) during 8 days. At the 4th day of treatment, they received a single dose of Dox (20 mg/kg bw). After the treatment (9th day), livers were collected and processed for oxidative stress status. Dox increased MDA (+ 900%), decreased catalase (-60%) and increased peroxidase (+90%) and superoxide dismutase (+100%) activities. In this latter case Dox mainly increased the iron isoform. Furthermore Dox altered intracellular mediators as catalytic free iron (-75%), H2O2(-75%) and calcium (+30%). Dox also affected liver function by elevating plasma triacylglycerol and transaminases and liver morphology by altering its typical architecture. Importantly all Dox-induced liver disturbances were alleviated upon GSSE treatment. Dox induced liver toxicity and an oxidative stress mainly characterized by increased lipoperoxidation but not protein carbonylation. GSSE efficiently protected the liver from Dox-induced toxicity and appeared as a safe adjuvant that could be incorporated into chemotherapy protocols.

Resveratrol Provides Cardioprotection after Ischemia/reperfusion Injury via Modulation of Antioxidant Enzyme Activities.

In this study, we investigated the cardioprotective effects of resveratrol. Rats were intraperitoneally administered with resveratrol (25 mg/kg bw) or vehicle (ethanol 10%) for 7 days and their heart subjected to ischemia/reperfusion injury. Isolated hearts were langendorff perfused, left ventricular functions as heart rate and developed pressure, as well as, heart antioxidant status were determined. Data showed that resveratrol improved recovery of post-ischemic ventricular functions when compared to control. Resveratrol also improved myocardial lipoperoxidation, free iron and antioxidant enzyme activities. Resveratrol decreased significantly catalase while it increased peroxidase and superoxide dismutase activities. In this later case, native PAGE analysis of superoxide dismutase isoforms revealed that resveratrol up regulated iron and manganese isoforms. Resveratrol exerted potential cardioprotection partly by its antioxidant properties.

Absence of tumor suppressor tumor protein 53-induced nuclear protein 1 (TP53INP1) sensitizes mouse thymocytes and embryonic fibroblasts to redox-driven apoptosis.

The p53-transcriptional target TP53INP1 is a potent stress-response protein promoting p53 activity. We previously showed that ectopic overexpression of TP53INP1 facilitates cell cycle arrest as well as cell death. Here we report a study investigating cell death in mice deficient for TP53INP1. Surprisingly, we found enhanced stress-induced apoptosis in TP53INP1-deficient cells. This observation is underpinned in different cell types in vivo (thymocytes) and in vitro (thymocytes and MEFs), following different types of injury inducing either p53-dependent or -independent cell death. Nevertheless, absence of TP53INP1 is unable to overcome impaired cell death of p53-deficient thymocytes. Stress-induced ROS production is enhanced in the absence of TP53INP1, and antioxidant NAC complementation abolishes increased sensitivity to apoptosis of TP53INP1-deficient cells. Furthermore, antioxidant defenses are defective in TP53INP1-deficient mice in correlation with ROS dysregulation. Finally, we show that autophagy is reduced in TP53INP1-deficient cells both at the basal level and upon stress. Altogether, these data show that impaired ROS regulation in TP53INP1-deficient cells is responsible for their sensitivity to induced apoptosis. In addition, they suggest that this sensitivity could rely on a defect of autophagy. Therefore, these data emphasize the role of TP53INP1 in protection against cell injury.