BACKGROUND Antagonists of cannabinoid type 1 receptor(CB1)have been shown to promote body weight loss and improve insulin sensitivity.Cannabinoids decrease adiponectin,and CB1 blocker increase adiponectin.However,the ...BACKGROUND Antagonists of cannabinoid type 1 receptor(CB1)have been shown to promote body weight loss and improve insulin sensitivity.Cannabinoids decrease adiponectin,and CB1 blocker increase adiponectin.However,the mediators of CB1 actions are not well defined.AIM To investigate whether the beneficial effects of CB1 inhibition are,at least in part,mediated by adiponectin.METHODS We compared metabolic and inflammatory phenotypes of wild-type(WT)mice,CB1-null(CB1^(-/-))and CB1/adiponectin double-knockout(DKO)mice.We assessed the insulin sensitivity using insulin tolerance test and glucose tolerance test,and inflammation using flow cytometry analysis of macrophages.RESULTS CB1^(-/-)mice exhibited significantly reduced body weight and fat mass when compared to WT mice.While no significance was found in total daily food intake and locomotor activity,CB1^(-/-)mice showed increased energy expenditure,enhanced thermogenesis in brown adipose tissue(BAT),and improved insulin sensitivity compared to WT mice.DKO showed no difference in body weight,adiposity,nor insulin sensitivity;only showed a modestly elevated thermogenesis in BAT compared to CB1^(-/-)mice.The metabolic phenotype of DKO is largely similar to CB1^(-/-)mice,suggesting that adiponectin is not a key mediator of the metabolic effects of CB1.Interestingly,CB1^(-/-)mice showed reduced pro-inflammatory macrophage polarization in both peritoneal macrophages and adipose tissue macrophages compared to WT mice;in contrast,DKO mice exhibited increased pro-inflammatory macrophage polarization in these macrophages compared to CB1^(-/-)mice,suggesting that adiponectin is an important mediator of the inflammatory effect of CB1.CONCLUSION Our findings reveal that CB1 functions through both adiponectin-dependent and adiponectin-independent mechanisms:CB1 regulates energy metabolism in an adiponectin-independent manner,and inflammation in an adiponectin-dependent manner.The differential effects of adiponectin on CB1-mediated metabolic and inflammatory functions should be taken into consideration in CB1 antagonist utilization.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。
基金Supported by the NIH,No.DK118334 and No.AG064869and the BrightFocus,No.A2019630S(to Sun Y).
文摘BACKGROUND Antagonists of cannabinoid type 1 receptor(CB1)have been shown to promote body weight loss and improve insulin sensitivity.Cannabinoids decrease adiponectin,and CB1 blocker increase adiponectin.However,the mediators of CB1 actions are not well defined.AIM To investigate whether the beneficial effects of CB1 inhibition are,at least in part,mediated by adiponectin.METHODS We compared metabolic and inflammatory phenotypes of wild-type(WT)mice,CB1-null(CB1^(-/-))and CB1/adiponectin double-knockout(DKO)mice.We assessed the insulin sensitivity using insulin tolerance test and glucose tolerance test,and inflammation using flow cytometry analysis of macrophages.RESULTS CB1^(-/-)mice exhibited significantly reduced body weight and fat mass when compared to WT mice.While no significance was found in total daily food intake and locomotor activity,CB1^(-/-)mice showed increased energy expenditure,enhanced thermogenesis in brown adipose tissue(BAT),and improved insulin sensitivity compared to WT mice.DKO showed no difference in body weight,adiposity,nor insulin sensitivity;only showed a modestly elevated thermogenesis in BAT compared to CB1^(-/-)mice.The metabolic phenotype of DKO is largely similar to CB1^(-/-)mice,suggesting that adiponectin is not a key mediator of the metabolic effects of CB1.Interestingly,CB1^(-/-)mice showed reduced pro-inflammatory macrophage polarization in both peritoneal macrophages and adipose tissue macrophages compared to WT mice;in contrast,DKO mice exhibited increased pro-inflammatory macrophage polarization in these macrophages compared to CB1^(-/-)mice,suggesting that adiponectin is an important mediator of the inflammatory effect of CB1.CONCLUSION Our findings reveal that CB1 functions through both adiponectin-dependent and adiponectin-independent mechanisms:CB1 regulates energy metabolism in an adiponectin-independent manner,and inflammation in an adiponectin-dependent manner.The differential effects of adiponectin on CB1-mediated metabolic and inflammatory functions should be taken into consideration in CB1 antagonist utilization.
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.
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。
