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 o...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 fatfed 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 BE)L-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 findings have been described in humans. Diminished hepatic expression of adiponectin receptors was only found in liver cirrhosis.展开更多
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 fatfed 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 BE)L-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 findings have been described in humans. Diminished hepatic expression of adiponectin receptors was only found in liver cirrhosis.
文摘目的:阐明锌-α2-糖蛋白(Zinc-α2-glycoprotein,ZAG)与胰岛素抵抗的关系以及胰升糖素样肽1(glucagon-like peptide-1,GLP-1)受体激动剂治疗的影响。方法:新发2型糖尿病(newly diagnosed T2DM,n T2DM)患者120例随机分为利拉鲁肽组(n=45,利拉鲁肽0.6~1.8 mg,i H qd)、利拉鲁肽+二甲双胍组(n=45,利拉鲁肽0.6~1.8 mg,i H qd+二甲双胍0.5g bid)、安慰剂组(n=30,生理盐水150μl i H qd+二甲双胍0.5g bid),治疗12周,同期选取年龄、性别相匹配的健康体检者作为健康对照组(n=30)。治疗前后分别行75g OGTT、胰岛素钳夹试验并检测血浆ZAG、脂联素(adiponectin,ADI)水平及相关代谢指标。结果:n T2DM患者基础血浆ZAG水平明显低于健康对照组(P<0.01),通过利拉鲁肽、利拉鲁肽+二甲双胍治疗后12周,患者的糖化血红蛋白,空腹血糖,糖负荷后2 h血糖,甘油三酯和稳态模型评估胰岛素抵抗指数均较治疗前明显下降(P<0.05),通过安慰剂治疗后上述指标明显高于利拉鲁肽治疗组(P<0.05);而在钳夹过程中,M值明显升高(P<0.01)。此外,与治疗前相比,利拉鲁肽治疗后血浆ZAG、ADI水平明显增加(P<0.01)。结论:n T2DM患者经GLP-1受体激动剂治疗后,糖代谢及胰岛素敏感性得到明显改善,血浆ZAG水平也明显升高,提示ZAG将可能被作为代谢综合征或者T2DM的一个新的生物标志物。