Background Endothelial dysfunction is a key event in the onset and progression of atherosclerosis in diabetic patients. Apoptosis may lead to endothelial dysfunction and contribute to vascular complications. However, ...Background Endothelial dysfunction is a key event in the onset and progression of atherosclerosis in diabetic patients. Apoptosis may lead to endothelial dysfunction and contribute to vascular complications. However, no study has addressed apoptosis in human umbilical vein endothelial cells (HUVECs) induced by an intermittent high-glucose media and its association with adiponectin receptor 1 (adipoR1), adipoR2, or adenosine monophosphate (AMP)-activated protein kinase (AMPK). Methods HUVECs were cultured in continuous normal glucose (5.5 mmol/L), continuous high glucose (25 mmol/L), alternating normal and high glucose and mannitol. In the alternating normal and high-glucose media, HUVECs were treated under different conditions. First, cells were transfected with the adipoRl-specific small-interfering RNA (siRNA) and then stimulated with globular adiponectin (gAD). Second, cells were cultured in both gAD and the AMPK activator 5-aminoimidazole-4-carboxamide-l-13-D-ribofuranoside (AICAR). Third, cells were cultured in the AMPK inhibitor adenine-9-13-D-arabino-furanoside (araA), gAD, and in AICAR. Results HUVEC apoptosis increased more significantly in an intermittent high-glucose medium than in a constant high-glucose medium. HUVEC apoptosis induced by an intermittent high-glucose medium was inhibited when the cells were pretreated with 3 pg/ml gAD, which rapidly activated AMPK and adipoR1 in HUVECs. However, adipoR2 was not activated. Conclusions We found that adipoR1, not adipoR2, is involved in mediating intermittent high-concentration glucose- evoked apoptosis in endothelial cells, gAD activated AMPK through adipoR1, leads to the partial inhibition of HUVEC apoptosis. A fluctuating glucose medium is more harmful than a constant high-glucose medium to endothelial cells.展开更多
AIM: To determine circulating and hepatic adiponectin in rodents with fatty liver disease or liver cirrhosis and investigate expression of the adiponectin receptors AdipoR1 on the mRNA and protein level and AdipoR2 on...AIM: To determine circulating and hepatic adiponectin in rodents with fatty liver disease or liver cirrhosis and investigate expression of the adiponectin receptors AdipoR1 on the mRNA and protein level and AdipoR2 on the mRNA level. METHODS: Fat fed rats were used as a model for fatty liver disease and bile duct ligation in mice to investigate cirrhotic liver. Expression of AdipoR1 and AdipoR2 mRNA was determined by real time RT-PCR. AdipoR1 protein was analysed by immunoblot. Adiponectin was measured by ELISA. RESULTS: Systemic adiponectin is reduced in fat- fed rats but is elevated in mice after bile duct ligation (BDL). Hepatic adiponectin protein is lower in steatotic liver but not in the liver of BDL-mice when compared to controls. Adiponectin mRNA was not detected in human liver samples or primary human hepatocytes nor in rat liver but recombinant adiponectin is taken up by isolated hepatocytes in-vitro. AdipoR1 mRNA and AdipoR1 protein levels are similar in the liver tissue of control and fat fed animals whereas AdipoR2 mRNA is induced. AdipoR2 mRNA and AdipoR1 mRNA and protein is suppressed in the liver of BDL-mice. CONCLUSION: Our studies show reduced circulating adiponectin in a rat model of fatty liver disease whereas circulating adiponectin is elevated in a mouse model of cirrhosis and similar fi ndings have been described in humans. Diminished hepatic expression of adiponectinreceptors was only found in liver cirrhosis.展开更多
基金Acknowledgments This study was funded by the National Natural Science Foundation of China (81570323, 30972709, 81061120527, 81241082) and the 12th Five-Year National Program of the Ministry of Scientific Technology (2012BAI10B01). We thank Liu M and Zhou L from Beijing Hospital for providing experimental data, the nurses from Beijing Anzhen Hospital for collecting specimens, and the study volunteers.
文摘编码 adiponectin 受体 1 的基因( ADIPOR1 )和小象ubiquitin一样修饰词( SUMO4 ) 4 被连接了到 anti-atherogenic 效果,但是很少对是否被知道在二基因的多型性,独立行动或交往,没有 diabetes.MethodsWe genotyped ,影响冠的动脉疾病( CAD )的风险没有糖尿病的 200 个 CAD 病人和没有 CAD 的 200 控制,它被选择基于前一个没有 diabetes.ResultsRisk 等位基因,协会也是的潜力在 ADIPOR1 (rs7539542-G, rs7514221-C 和 rs3737884-G ) 在三 SNP 在这些 SNP 和 CAD 的临床的特征之间探索了,没有糖尿病,在在 SUMO4 的 SNP rs237025 的 G 等位基因显著地增加了 CAD 的风险,与从 1.79 ~ 4.44 的 ORs。任何这四风险等位基因的搬运人出现了类似不利 ? 临床的特征。与有 CC 或 GC 遗传型的个人相比,有在 rs3737884 的 GG 遗传型的那些在影响了左前面的下降冠的动脉的 CAD 的显著地更高的风险(或:6.77, P = 0.009 ) ,恰好冠的动脉(或:4.81, P = 0.028 ) 或容器的一个相对大的数字(P = 0.04 ) 。没有糖尿病,在 SUMO4 在 SNP 象风险等位基因一样在 ADIPOR1 在三 SNP 中的至少一个带风险等位基因的个人比不带任何风险等位基因的个人在 CAD 的显著地更高的风险(或:5.82, 95% CI:1.2327.7, P = 0.013 ) 没有糖尿病,在 ADIPOR1 和 SUMO4 的 .ConclusionsSNPs 与 CAD 的提高的风险被联系,并且在二基因的 SNP 可以交往联合影响疾病风险。
文摘Background Endothelial dysfunction is a key event in the onset and progression of atherosclerosis in diabetic patients. Apoptosis may lead to endothelial dysfunction and contribute to vascular complications. However, no study has addressed apoptosis in human umbilical vein endothelial cells (HUVECs) induced by an intermittent high-glucose media and its association with adiponectin receptor 1 (adipoR1), adipoR2, or adenosine monophosphate (AMP)-activated protein kinase (AMPK). Methods HUVECs were cultured in continuous normal glucose (5.5 mmol/L), continuous high glucose (25 mmol/L), alternating normal and high glucose and mannitol. In the alternating normal and high-glucose media, HUVECs were treated under different conditions. First, cells were transfected with the adipoRl-specific small-interfering RNA (siRNA) and then stimulated with globular adiponectin (gAD). Second, cells were cultured in both gAD and the AMPK activator 5-aminoimidazole-4-carboxamide-l-13-D-ribofuranoside (AICAR). Third, cells were cultured in the AMPK inhibitor adenine-9-13-D-arabino-furanoside (araA), gAD, and in AICAR. Results HUVEC apoptosis increased more significantly in an intermittent high-glucose medium than in a constant high-glucose medium. HUVEC apoptosis induced by an intermittent high-glucose medium was inhibited when the cells were pretreated with 3 pg/ml gAD, which rapidly activated AMPK and adipoR1 in HUVECs. However, adipoR2 was not activated. Conclusions We found that adipoR1, not adipoR2, is involved in mediating intermittent high-concentration glucose- evoked apoptosis in endothelial cells, gAD activated AMPK through adipoR1, leads to the partial inhibition of HUVEC apoptosis. A fluctuating glucose medium is more harmful than a constant high-glucose medium to endothelial cells.
基金Supported by a grant from the Deutsche Forschungsgemeinschaft (BU 1141/3-2)
文摘AIM: To determine circulating and hepatic adiponectin in rodents with fatty liver disease or liver cirrhosis and investigate expression of the adiponectin receptors AdipoR1 on the mRNA and protein level and AdipoR2 on the mRNA level. METHODS: Fat fed rats were used as a model for fatty liver disease and bile duct ligation in mice to investigate cirrhotic liver. Expression of AdipoR1 and AdipoR2 mRNA was determined by real time RT-PCR. AdipoR1 protein was analysed by immunoblot. Adiponectin was measured by ELISA. RESULTS: Systemic adiponectin is reduced in fat- fed rats but is elevated in mice after bile duct ligation (BDL). Hepatic adiponectin protein is lower in steatotic liver but not in the liver of BDL-mice when compared to controls. Adiponectin mRNA was not detected in human liver samples or primary human hepatocytes nor in rat liver but recombinant adiponectin is taken up by isolated hepatocytes in-vitro. AdipoR1 mRNA and AdipoR1 protein levels are similar in the liver tissue of control and fat fed animals whereas AdipoR2 mRNA is induced. AdipoR2 mRNA and AdipoR1 mRNA and protein is suppressed in the liver of BDL-mice. CONCLUSION: Our studies show reduced circulating adiponectin in a rat model of fatty liver disease whereas circulating adiponectin is elevated in a mouse model of cirrhosis and similar fi ndings have been described in humans. Diminished hepatic expression of adiponectinreceptors was only found in liver cirrhosis.