AIM： To investigate the effect of polaprezinc on cellular damage induced by hydrogen peroxide （H202） in human colon CaCo2 cells. METHODS： CaCo2 cells were treated with polaprezinc （10-100 pmol/L） for 6 h. After ...AIM： To investigate the effect of polaprezinc on cellular damage induced by hydrogen peroxide （H202） in human colon CaCo2 cells. METHODS： CaCo2 cells were treated with polaprezinc （10-100 pmol/L） for 6 h. After polaprezinc treatment, the cells were incubated with H202 （20μmol/L） for 1 h. Cell viability was measured by MTT assay. Western blot analysis for heat shock protein （HSP） 27 and HSP72 in the cells was performed. Moreover, cells were pretreated with quercetin （200 μmol/L）, an inhibitor of HSP synthesis, 2 h before polaprezinc treatment, and cell viability and the expression of HSP27 and 72 were assessed in these cells. RESULTS： Polaprezinc significantly protected CaCo2 cells from cell damage induced by H2O2, and up-regulated the expressions of HSP27 and HSP72 in the cells （10, 30 and 100 pmol/L of polaprezinc; 35.0% ± 7.7%, 58.3% ± 14.6% and 64.2% ± 8.2%, respectively. P 〈 0.01 versus polaprezinc-nontreated cells; 6.0% ± 4.4%）. Quercetin inhibited the up-regulation of HSP27 and HSP72 by polaprezinc and diminished the protective effect of polaprezinc against H2O2-caused injury in the cells. CONCLUSION： Polaprezinc is a useful therapeutic agent for treatment of colitis and its effects depend on the function of cytoprotective HSP in colon.展开更多
AIM： To investigate the hypothesis that the protective effects of curcumin in hepatic warm ischemia/reperfusion （I/R） injury are associated with increasing heat shock protein 70 （Hsp70） expression and antioxidant...AIM： To investigate the hypothesis that the protective effects of curcumin in hepatic warm ischemia/reperfusion （I/R） injury are associated with increasing heat shock protein 70 （Hsp70） expression and antioxidant enzyme activity. METHODS： Sixty Sprague-Dawley male rats were randomly divided into sham, I/R, C ＋ I/R groups. The model of reduced-size liver warm ischemia and reperfusion was used. Curcumin （50 mg/kg） was administered by injection through a branch of superior mesenteric vein at 30 min before ischemia in C ＋ I/R group. Five rats were used to investigate the survival during 1 wk after operation in each group. Blood samples and liver tissues were obtained in the remaining animals after 3, 12, and 24 h of reperfusion to assess serum alanine aminotransferase （ALT）, aspartate aminotransferase （AST）, liver tissue NO2- ＋ NO3-, malondialdehyde （MDA） content, superoxide dismutase （SOD）, catalase （CAT）, nitricoxide synthase （NOS） and myeloperoxidase （MPO） activity, HspT0 expression and apoptosis ratio. RESULTS： Compared with I/R group, curcumin pretreatment group showed less ischemia/reperfusioninduced injury. CAT and SOD activity and Hsp70 expression increased significantly. A higher rate of apoptosis was observed in I/R group than in C ＋ I/R group, and a significant increase of MDA, NO2^- ＋ NO3^- and MPO level in liver tissues and serum transaminase concentration was also observed in I/R group compared to C ＋ I/R group. Curcumin also decreased the activity of inducible NO synthase （iNOS） in liver after reperfusion,but had no effect on the level of endothelial NO synthase （eNOS） after reperfusion in liver. The 7 d survival rate was significantly higher in C ＋ I/R group than in I/R group. CONCLUSION： Curcumin has protective effects against hepatic I/R injury. Its mechanism might be related to the overexpression of Hsp70 and antioxidant enzymes.展开更多
Objective： To investigate the protective effects of acuptmcture pretreatment on ischemic myocardium, the protective mechanism of acupuncture pretreatment on ischemic myocardium was explored by observing the cardiac m...Objective： To investigate the protective effects of acuptmcture pretreatment on ischemic myocardium, the protective mechanism of acupuncture pretreatment on ischemic myocardium was explored by observing the cardiac muscle cell apoptosis and the expression of HSP70 mRNA of ischemia-reperfusion injury rats treated with acupuncture pretreatment. Methods： Sixty-four Wistar rats were randomly divided into eight groups： control group, sham surgery group, ischemia-reperfusion group, ischemia pretreatment group, manual acupuncture pretreatment group （once a day）, electroacupuncture pretreatment group （once a day）, manual acupuncture pretreatment group （twice a day）, and electroacupuncture pretreatment group （twice a day）. The reperfusion model of rat myocardial ischemia was made. Expression of HSP70 mRNA was assayed by in situ hybridization, and cell apoptosis by TUNEL. Results： Compared with those in the control group and the sham surgery group, the apoptosis and the expression of HSP70 mRNA were increased in the ischemia-reperfusion group. Compared with those in the ischemia-reperfusion group, the cardiac muscle cell apoptosis was decreased and the HSP70 mRNA was increased in the rats treated with acupuncture pretreatment; meanwhile, acupuncture pretreatment twice a day had stronger effects than acupuncture pretreatment once a day and ischemia pretreatrnent. Conclusion： Acupuncture pretreatment can inhibit the cardiac muscle cell apoptosis, and up-regulate the expression of HSP70 mRNA in ischemia-reperfusion rats. Acupuncture pretreatment twice a day has stronger effects than pretreatment once a day.展开更多
Objective： To investigate the expres- sion of Caspase-3 and Hsp70 in rabbits after severe trau- matic brain injury （TBI） and to explore the feasibility of its application in estimation of injury time in forensic me...Objective： To investigate the expres- sion of Caspase-3 and Hsp70 in rabbits after severe trau- matic brain injury （TBI） and to explore the feasibility of its application in estimation of injury time in forensic medicine. Methods： Arabbit model of heavy TBI was developed by high velocity impact on the parietal bone with an iron stick. Totally 8 healthy adult New Zealand white rabbits were randomly divided into control group （n=2） and injury group （n=6）. Four hours after injury, tissue specimens from the parietal lobe, temporal lobe, occipital lobe, cerebellum and brainstem were harvested to detect the expression of Hsp70 and Caspase-3 by immunohistochemistry. Besides, the gray values of cells positive for HspT0 and Caspase-3 were analyzed with an image analyzer. Results： Immunohistochemistry staining demonstrated a low level of Caspase-3 and Hsp70 expression in normal control group. While in injury group, both the Caspase-3 and Hsp70 expression was significantly elevated （P〈0.05）. Positive cells gathered around the lesion focus. Occipital lobe and cerebellum had fewer positive cells while temporal and brainstem had the fewest. Conclusion： The expression of Caspase-3 and HspT0 at an early stage following severe TBI is characteristic and can be applied to estimate the time of injury.展开更多
基金Supported by the Grant-in-Aid for research, No.18590665 from the Ministry of Education, Science and Culture of Japan
文摘AIM： To investigate the effect of polaprezinc on cellular damage induced by hydrogen peroxide （H202） in human colon CaCo2 cells. METHODS： CaCo2 cells were treated with polaprezinc （10-100 pmol/L） for 6 h. After polaprezinc treatment, the cells were incubated with H202 （20μmol/L） for 1 h. Cell viability was measured by MTT assay. Western blot analysis for heat shock protein （HSP） 27 and HSP72 in the cells was performed. Moreover, cells were pretreated with quercetin （200 μmol/L）, an inhibitor of HSP synthesis, 2 h before polaprezinc treatment, and cell viability and the expression of HSP27 and 72 were assessed in these cells. RESULTS： Polaprezinc significantly protected CaCo2 cells from cell damage induced by H2O2, and up-regulated the expressions of HSP27 and HSP72 in the cells （10, 30 and 100 pmol/L of polaprezinc; 35.0% ± 7.7%, 58.3% ± 14.6% and 64.2% ± 8.2%, respectively. P 〈 0.01 versus polaprezinc-nontreated cells; 6.0% ± 4.4%）. Quercetin inhibited the up-regulation of HSP27 and HSP72 by polaprezinc and diminished the protective effect of polaprezinc against H2O2-caused injury in the cells. CONCLUSION： Polaprezinc is a useful therapeutic agent for treatment of colitis and its effects depend on the function of cytoprotective HSP in colon.
文摘AIM： To investigate the hypothesis that the protective effects of curcumin in hepatic warm ischemia/reperfusion （I/R） injury are associated with increasing heat shock protein 70 （Hsp70） expression and antioxidant enzyme activity. METHODS： Sixty Sprague-Dawley male rats were randomly divided into sham, I/R, C ＋ I/R groups. The model of reduced-size liver warm ischemia and reperfusion was used. Curcumin （50 mg/kg） was administered by injection through a branch of superior mesenteric vein at 30 min before ischemia in C ＋ I/R group. Five rats were used to investigate the survival during 1 wk after operation in each group. Blood samples and liver tissues were obtained in the remaining animals after 3, 12, and 24 h of reperfusion to assess serum alanine aminotransferase （ALT）, aspartate aminotransferase （AST）, liver tissue NO2- ＋ NO3-, malondialdehyde （MDA） content, superoxide dismutase （SOD）, catalase （CAT）, nitricoxide synthase （NOS） and myeloperoxidase （MPO） activity, HspT0 expression and apoptosis ratio. RESULTS： Compared with I/R group, curcumin pretreatment group showed less ischemia/reperfusioninduced injury. CAT and SOD activity and Hsp70 expression increased significantly. A higher rate of apoptosis was observed in I/R group than in C ＋ I/R group, and a significant increase of MDA, NO2^- ＋ NO3^- and MPO level in liver tissues and serum transaminase concentration was also observed in I/R group compared to C ＋ I/R group. Curcumin also decreased the activity of inducible NO synthase （iNOS） in liver after reperfusion,but had no effect on the level of endothelial NO synthase （eNOS） after reperfusion in liver. The 7 d survival rate was significantly higher in C ＋ I/R group than in I/R group. CONCLUSION： Curcumin has protective effects against hepatic I/R injury. Its mechanism might be related to the overexpression of Hsp70 and antioxidant enzymes.
文摘Objective： To investigate the protective effects of acuptmcture pretreatment on ischemic myocardium, the protective mechanism of acupuncture pretreatment on ischemic myocardium was explored by observing the cardiac muscle cell apoptosis and the expression of HSP70 mRNA of ischemia-reperfusion injury rats treated with acupuncture pretreatment. Methods： Sixty-four Wistar rats were randomly divided into eight groups： control group, sham surgery group, ischemia-reperfusion group, ischemia pretreatment group, manual acupuncture pretreatment group （once a day）, electroacupuncture pretreatment group （once a day）, manual acupuncture pretreatment group （twice a day）, and electroacupuncture pretreatment group （twice a day）. The reperfusion model of rat myocardial ischemia was made. Expression of HSP70 mRNA was assayed by in situ hybridization, and cell apoptosis by TUNEL. Results： Compared with those in the control group and the sham surgery group, the apoptosis and the expression of HSP70 mRNA were increased in the ischemia-reperfusion group. Compared with those in the ischemia-reperfusion group, the cardiac muscle cell apoptosis was decreased and the HSP70 mRNA was increased in the rats treated with acupuncture pretreatment; meanwhile, acupuncture pretreatment twice a day had stronger effects than acupuncture pretreatment once a day and ischemia pretreatrnent. Conclusion： Acupuncture pretreatment can inhibit the cardiac muscle cell apoptosis, and up-regulate the expression of HSP70 mRNA in ischemia-reperfusion rats. Acupuncture pretreatment twice a day has stronger effects than pretreatment once a day.
基金The paper was supported by the National Natural Science Foundation of China，the Natural Science Foundation of Chongqing of China，the Key Projects Foundation of the Ministry of Public Security
文摘Objective： To investigate the expres- sion of Caspase-3 and Hsp70 in rabbits after severe trau- matic brain injury （TBI） and to explore the feasibility of its application in estimation of injury time in forensic medicine. Methods： Arabbit model of heavy TBI was developed by high velocity impact on the parietal bone with an iron stick. Totally 8 healthy adult New Zealand white rabbits were randomly divided into control group （n=2） and injury group （n=6）. Four hours after injury, tissue specimens from the parietal lobe, temporal lobe, occipital lobe, cerebellum and brainstem were harvested to detect the expression of Hsp70 and Caspase-3 by immunohistochemistry. Besides, the gray values of cells positive for HspT0 and Caspase-3 were analyzed with an image analyzer. Results： Immunohistochemistry staining demonstrated a low level of Caspase-3 and Hsp70 expression in normal control group. While in injury group, both the Caspase-3 and Hsp70 expression was significantly elevated （P〈0.05）. Positive cells gathered around the lesion focus. Occipital lobe and cerebellum had fewer positive cells while temporal and brainstem had the fewest. Conclusion： The expression of Caspase-3 and HspT0 at an early stage following severe TBI is characteristic and can be applied to estimate the time of injury.
