Neuroprotective Effects of Grape Seed Procyanidin Extracton Ischemia-Reperfusion Brain Injury

Objective Oxidative stress （OS） plays a crucial role in ischemic stroke. Grape seed procyanidin extract （GSPE） was reported to be a critical regulator of OS. We hypothesized that GSPE might also be protective in ischemia-reperfusion brain injury. This study aimed to explore whether GSPE administration can protect mice from ischemia-reperfusion brain injury. Methods Transient middle cerebral artery occlusion （MCAO） was conducted followed by reperfusion for 24 hours to make ischemia-reperfusion brain injury in mice that received GSPE （MCAOG, n=60） or normal saline （MCAONS, n=60）. Sham-operated mice （GSPE group and normal saline group） were set as controls. The neurological severity score （NSS） was used to evaluate neural function impairment 1 hour, 24 hour, 3 days and 7 days after MCAO. Mice underwent brain T2WI imaging with a 3T animal MRI scanner 24 hours after reperfusion, and the stroke volume of brains were calculated according to abnormal signal intensity. Immunohistopathological analysis of brain tissues at 24 h after reperfusion was performed for neuronal nuclear antigen （NeuN）, CD34, Bcl-2, and Bax. Glutathione peroxidation （GSH-Px） activity and the level of malonaldehyde （MDA） of brain tissue were also examined. The above indexes were compared among the groups statistically.Results Significant functional improvement was observed 24 hours after MCAO in MCAOG group compared to MCAONS group （P〈0.05）. MCAOG group had smaller cerebral stroke volume （22.46 ± 11.45 mm3 vs. 47.84±9.06 mm3, P〈0.05） than MCAONS group 24 hours after MCAO. More mature NeuN-immunoreactive neurons and more CD34-positive cells in peri-infarct zones were observed in brain tissue of MCAOG mice 24 h after MCAO than that of MCAONS mice （both P〈0.05）. MCAONS mice had significantly higher number of Bax-positive cells in brain tissue than MCAOG （P〈0.05）. The mean MDA level was significantly lower （P〈0.05） and the GSH-Px activity was significantly higher （P〈0.05） in brains of MCAOG mice compared to those of MCAONS mice. Conclusion GSPE administration protects mice from ischemia-reperfusion brain injury through attenuating oxidative stress and apoptosis, promoting angiogenesis, and activating antioxidant enzyme GSH-Px. GSPE may represent a new therapeutical direction for the treatment of ischemia-reperfusion brain injury.

Grape Seed Procyanidin Extract Reduces Arsenic- Induced Renal Inflammatory Injury in Male Mice

The aim of the present study is to evaluate the ability and mechanism by which grape seed procyanidin extract （GSPE） relieves arsenic trioxide （As2O3）-induced renal inflammatory injury. Therefore, male Kunming mice were treated with As2O3 and/or GSPE by gavage for 5 weeks. Mice were then sacrificed and inflammatory cytokines of kidneys were examined by ELISA, whereas the expression levels of molecules involved in the nuclear factor （NF）-KB signaling pathway were evaluated by both qRT-PCR and Western blot. Our results indicate that GSPE prevents As2O3-mediated renal inflammatory injury by inhibiting activation of the NF-KB signaling pathway and inflammatory cytokine production, while promoting expression of anti-inflammatory cytokines.

Role of survivin in apoptosis induced by grape seed procyanidin extract in human bladder cancer BIU87 cells

Objects： The aim of this study was to research the effect of grape seed procyanidin extract （GSPE） on cell apotosis in human bladder cancer BIU87 cells and investigate its molecular mechanism. Methods： BIU87 cells were treated with different concentrations of GSPE and cultured for 24 h in vitro while untreated group as control, MTT[3- （4,5-dimethylthiazole- 2-yl） -2, 5-diphenyltetrazolium bromide] assay, Hoechst 33258 stainning, flow cytometry, RT-PCR and Western blot were used to detect the apoptotic induction effect of GSPE on BIU87 cells. Results： We found that GSPE induced cell apoptosis in BIU87 cells by a dose-dependent manner. Semiquantitated RT-PCR and Western blot analyses indicated that GSPE increased the expression of caspase-3 and decreased the expression of survivin （P 〈 0.01）. Conclusion： GSPE induces apoptosis in BIU87 cells in vitro, and the effect maybe related with its down-regulation of survivin.