Objective: To investigate the relationship between oxidative stress and apoptosis and bcl-2 expression following traumatic brain injury (TBI). Methods: Male Sprague-Dawley rats were subjected to lateral fluid percussi...Objective: To investigate the relationship between oxidative stress and apoptosis and bcl-2 expression following traumatic brain injury (TBI). Methods: Male Sprague-Dawley rats were subjected to lateral fluid percussion brain injury (FPBI) of moderate severity. U-74389G (20 mg/kg) were administered intravenously before FPBI. The neurological functions were measured by beam-walk task (BWT) and beam-balance task (BBT). In addition to morphological evidence of apoptosis, TUNEL histochemistry was used to identify DNA fragmentation in situ with both light and electron microscopic levels. The internucleosomal fragments of DNA in apoptotic cells were examined using agarose gel electrophoresis. Bcl-2 protein expression was detected by immunohistochemistry. Results: The scores of BWT and BBT were significantly improved (P<0.01) in the treated animals. The treatment significantly reduced the number of apoptotic cells that was counted in the areas of the injured hemisphere at various time points following TBI. No DNA ladder was detected in the treated rats. Bcl-2 expression was observed in the cerebral cortex, subcortical white matter, dentate gyrus, hippocampal CA1 and CA3 region ipsilateral to injured hemisphere. Bcl-2 positive cells displayed normal nuclear morphology; Little Bcl-2 positive cells revealed morphological feature of apoptosis or necrosis. The immunoreactivity of Bcl-2 protein decreased significantly in the hippocampus ipsilateral impact site as early as 6 h post-injury. During 1-3 d after injury, the bcl-2 protein expression decreased relatively slow. In the U-74389G treated groups, the downregulation of bcl-2 expression was halted. Conclusion: In this model, apoptosis is associated with an activation of lipid peroxidation. U-74389G may block oxidative stress and halt the downregulation of bcl-2 expression. These may be one of the molecular mechanisms of the neuro-protective effects by U-74389G.展开更多
Objective To investigate the protective role of lazaroid U-74389G pretreatment against warm ischemia injury of rat liver transplantation from non-heart-beating donors. Methods Rat othortopic liver transplantation ...Objective To investigate the protective role of lazaroid U-74389G pretreatment against warm ischemia injury of rat liver transplantation from non-heart-beating donors. Methods Rat othortopic liver transplantation was perfomed in 4 groups (N-45, N-60, pN-45 and pN-60 ), according to pretreatment with U-74389G or not, and the non-heart-beating time 45rain or 60rain before donor liver harvested. Survival rates, liver functions, MDA values and graft pathology of each group were compared. Results The one-week survival rates of Group N-45, N-60 , pN-45 and pN-60 were25% (2/8), 0% (0/8), 58.3% (7/12) and 33.3% ( 4/12 ), respectively. U-74389G pretreatment significantly increased survival rate of rat liver trans-plantation from non-heart-beating donors, but also improved liver functions and graft pathologies, as well as decreased MDA expression. Conclusion U-74389G pretreatment could attenuate warm ischemia reperfusion injury of rat liver transplantation from non-heart-beating donors.展开更多
基金Supported by Directive Subject of Chinese PLA(No.96L036)
文摘Objective: To investigate the relationship between oxidative stress and apoptosis and bcl-2 expression following traumatic brain injury (TBI). Methods: Male Sprague-Dawley rats were subjected to lateral fluid percussion brain injury (FPBI) of moderate severity. U-74389G (20 mg/kg) were administered intravenously before FPBI. The neurological functions were measured by beam-walk task (BWT) and beam-balance task (BBT). In addition to morphological evidence of apoptosis, TUNEL histochemistry was used to identify DNA fragmentation in situ with both light and electron microscopic levels. The internucleosomal fragments of DNA in apoptotic cells were examined using agarose gel electrophoresis. Bcl-2 protein expression was detected by immunohistochemistry. Results: The scores of BWT and BBT were significantly improved (P<0.01) in the treated animals. The treatment significantly reduced the number of apoptotic cells that was counted in the areas of the injured hemisphere at various time points following TBI. No DNA ladder was detected in the treated rats. Bcl-2 expression was observed in the cerebral cortex, subcortical white matter, dentate gyrus, hippocampal CA1 and CA3 region ipsilateral to injured hemisphere. Bcl-2 positive cells displayed normal nuclear morphology; Little Bcl-2 positive cells revealed morphological feature of apoptosis or necrosis. The immunoreactivity of Bcl-2 protein decreased significantly in the hippocampus ipsilateral impact site as early as 6 h post-injury. During 1-3 d after injury, the bcl-2 protein expression decreased relatively slow. In the U-74389G treated groups, the downregulation of bcl-2 expression was halted. Conclusion: In this model, apoptosis is associated with an activation of lipid peroxidation. U-74389G may block oxidative stress and halt the downregulation of bcl-2 expression. These may be one of the molecular mechanisms of the neuro-protective effects by U-74389G.
文摘Objective To investigate the protective role of lazaroid U-74389G pretreatment against warm ischemia injury of rat liver transplantation from non-heart-beating donors. Methods Rat othortopic liver transplantation was perfomed in 4 groups (N-45, N-60, pN-45 and pN-60 ), according to pretreatment with U-74389G or not, and the non-heart-beating time 45rain or 60rain before donor liver harvested. Survival rates, liver functions, MDA values and graft pathology of each group were compared. Results The one-week survival rates of Group N-45, N-60 , pN-45 and pN-60 were25% (2/8), 0% (0/8), 58.3% (7/12) and 33.3% ( 4/12 ), respectively. U-74389G pretreatment significantly increased survival rate of rat liver trans-plantation from non-heart-beating donors, but also improved liver functions and graft pathologies, as well as decreased MDA expression. Conclusion U-74389G pretreatment could attenuate warm ischemia reperfusion injury of rat liver transplantation from non-heart-beating donors.
