Zinc-α2-glycoprotein(ZAG), encoded by the AZGP1 gene, is a major histocompatibility complex I molecule and a lipid-mobilizing factor. ZAG has been demonstrated to promote lipid metabolism and glucose utilization, and...Zinc-α2-glycoprotein(ZAG), encoded by the AZGP1 gene, is a major histocompatibility complex I molecule and a lipid-mobilizing factor. ZAG has been demonstrated to promote lipid metabolism and glucose utilization, and to regulate insulin sensitivity. Apart from adipose tissue, skeletal muscle, liver, and kidney, ZAG also occurs in brain tissue, but its distribution in brain is debatable. Only a few studies have investigated ZAG in the brain. It has been found in the brains of patients with Krabbe disease and epilepsy, and in the cerebrospinal fluid of patients with Alzheimer disease, frontotemporal lobe dementia, and amyotrophic lateral sclerosis. Both ZAG protein and AZGP1 m RNA are decreased in epilepsy patients and animal models, while overexpression of ZAG suppresses seizure and epileptic discharges in animal models of epilepsy, but knowledge of the specific mechanism of ZAG in epilepsy is limited. In this review, we summarize the known roles and molecular mechanisms of ZAG in lipid metabolism and glucose metabolism, and in the regulation of insulin sensitivity, and discuss the possible mechanisms by which it suppresses epilepsy.展开更多
Objective To explore the effects of zinc-0t2-glycoprotein （ZAG） on body weight and body fat in high-fat-diet （HF1））-induced obesity in mice and the possible mechanism. Methods Thirty-six male mice were fed with ...Objective To explore the effects of zinc-0t2-glycoprotein （ZAG） on body weight and body fat in high-fat-diet （HF1））-induced obesity in mice and the possible mechanism. Methods Thirty-six male mice were fed with standard food （SF） （n=9） and HFD （n=27）, respectively. Five weeks later, 9 mice fed with HFD were subjected to ZAG expression plasmid DNA transfection by liposome transfection method, and another 9 mice to negative control plasmid transfection. Two weeks later, serum ZAG level in the mice was assayed by Western blot, and the effects of ZAG over-expression on body weight, body fat, serum biochemical indexes, and adipose tissue of obese mice were evaluated. The mRNA expressions of fatty acid synthase （FAS） and hormone sensitive lipase （HSL） in liver tissue were deterlnined by reverse transcription-polymerase chain reaction. Results Serum ZAG level significantly lowered in simple HFD-fed mice in comparison to SF-fed mice （0.51±0.10 AU vs. 0.75±0.07 AU, P〈0.01）. Further statistical analysis demonstrated that ZAG level was negatively correlated with body weight （r =-0.56, P〈0.001）, epididymal fat mass （r=-0.67, P〈O. 001）, percentage of epididymal fat （r= 0.65, P〈0.001）, and increased weight （r= 0.57, P〈0.001） in simple SF- and HFD fed mice. ZAG over-expression in obese mice reduced body weight and the percentage of epididyreal fat. Furthermore, FAS mRNA expression decreased （P〈0.01） and HSL mRNA expression increased （P〈0.001） in the liver in ZAG over-expressing mice. Conclusions ZAG is closely related to obesity. Serum ZAG level is inversely correlated with body weight and percentage of body fat. The action of ZAG is associated with reduced FAS expression and increased HSL expression in the liver of obese mice.展开更多
BACKGROUND Zinc-α2-glycoprotein 1 (AZGP1) plays important roles in metabolism-related diseases. The underlying molecular mechanisms and therapeutic effects of AZGP1 remain unknown in non-alcoholic fatty liver disease...BACKGROUND Zinc-α2-glycoprotein 1 (AZGP1) plays important roles in metabolism-related diseases. The underlying molecular mechanisms and therapeutic effects of AZGP1 remain unknown in non-alcoholic fatty liver disease (NAFLD). AIM To explore the effects and potential mechanism of AZGP1 on NAFLD in vivo and in vitro. METHODS The expression of AZGP1 and its effects on hepatocytes were examined in NAFLD patients, CCl4-treated mice fed a high fat diet (HFD), and human LO2 cells. RESULTS AZGP1 levels were significantly decreased in liver tissues of NAFLD patients and mice. AZGP1 knockdown was found to activate inflammation;enhance steatogenesis, including promoting lipogenesis [sterol regulatory elementbinding protein (SREBP)-1c, liver X receptor (LXR), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and stearoyl CoA desaturase 1 (SCD)-1], increasing lipid transport and accumulation [fatty acid transport protein (FATP), carnitine palmitoyl transferase (CPT)-1A, and adiponectin], and reducing fatty acid β-oxidation [farnesoid X receptor (FXR) and peroxisome proliferator-activated receptor (PPAR)-α];accelerate proliferation;and reverse apoptosis in LO2 cells. AZGP1 overexpression (OV-AZGP1) had the opposite effects. Furthermore, AZGP1 alleviated NAFLD by blocking TNF-α-mediated inflammation and intracellular lipid deposition, promoting proliferation, and inhibiting apoptosis in LO2 cells. Finally, treatment with OV-AZGP1 plasmid dramatically improved liver injury and eliminated liver fat in NAFLD mice. CONCLUSION AZGP1 attenuates NAFLD with regard to ameliorating inflammation, accelerating lipolysis, promoting proliferation, and reducing apoptosis by negatively regulating TNF-α. AZGP1 is suggested to be a novel promising therapeutic target for NAFLD.展开更多
基金supported by the National Natural Science Foundation of China(81771391,81401073)Chongqing Municipal Public Health Bureau,Chongqing People’s Municipal Government(20142026)the Program for Innovative Research Team of Chongqing Kuanren Hospital,China
文摘Zinc-α2-glycoprotein(ZAG), encoded by the AZGP1 gene, is a major histocompatibility complex I molecule and a lipid-mobilizing factor. ZAG has been demonstrated to promote lipid metabolism and glucose utilization, and to regulate insulin sensitivity. Apart from adipose tissue, skeletal muscle, liver, and kidney, ZAG also occurs in brain tissue, but its distribution in brain is debatable. Only a few studies have investigated ZAG in the brain. It has been found in the brains of patients with Krabbe disease and epilepsy, and in the cerebrospinal fluid of patients with Alzheimer disease, frontotemporal lobe dementia, and amyotrophic lateral sclerosis. Both ZAG protein and AZGP1 m RNA are decreased in epilepsy patients and animal models, while overexpression of ZAG suppresses seizure and epileptic discharges in animal models of epilepsy, but knowledge of the specific mechanism of ZAG in epilepsy is limited. In this review, we summarize the known roles and molecular mechanisms of ZAG in lipid metabolism and glucose metabolism, and in the regulation of insulin sensitivity, and discuss the possible mechanisms by which it suppresses epilepsy.
基金Supported by the National Natural Science Foundation of China (30771026)Beijing Natural Science Foundation (7082079)
文摘Objective To explore the effects of zinc-0t2-glycoprotein （ZAG） on body weight and body fat in high-fat-diet （HF1））-induced obesity in mice and the possible mechanism. Methods Thirty-six male mice were fed with standard food （SF） （n=9） and HFD （n=27）, respectively. Five weeks later, 9 mice fed with HFD were subjected to ZAG expression plasmid DNA transfection by liposome transfection method, and another 9 mice to negative control plasmid transfection. Two weeks later, serum ZAG level in the mice was assayed by Western blot, and the effects of ZAG over-expression on body weight, body fat, serum biochemical indexes, and adipose tissue of obese mice were evaluated. The mRNA expressions of fatty acid synthase （FAS） and hormone sensitive lipase （HSL） in liver tissue were deterlnined by reverse transcription-polymerase chain reaction. Results Serum ZAG level significantly lowered in simple HFD-fed mice in comparison to SF-fed mice （0.51±0.10 AU vs. 0.75±0.07 AU, P〈0.01）. Further statistical analysis demonstrated that ZAG level was negatively correlated with body weight （r =-0.56, P〈0.001）, epididymal fat mass （r=-0.67, P〈O. 001）, percentage of epididymal fat （r= 0.65, P〈0.001）, and increased weight （r= 0.57, P〈0.001） in simple SF- and HFD fed mice. ZAG over-expression in obese mice reduced body weight and the percentage of epididyreal fat. Furthermore, FAS mRNA expression decreased （P〈0.01） and HSL mRNA expression increased （P〈0.001） in the liver in ZAG over-expressing mice. Conclusions ZAG is closely related to obesity. Serum ZAG level is inversely correlated with body weight and percentage of body fat. The action of ZAG is associated with reduced FAS expression and increased HSL expression in the liver of obese mice.
基金Supported by the National Natural Science Foundation of China,No.81570547 and No.81770597the Development Program of China during the 13~(th) Five-year Plan Period,No.2017ZX10203202003005
文摘BACKGROUND Zinc-α2-glycoprotein 1 (AZGP1) plays important roles in metabolism-related diseases. The underlying molecular mechanisms and therapeutic effects of AZGP1 remain unknown in non-alcoholic fatty liver disease (NAFLD). AIM To explore the effects and potential mechanism of AZGP1 on NAFLD in vivo and in vitro. METHODS The expression of AZGP1 and its effects on hepatocytes were examined in NAFLD patients, CCl4-treated mice fed a high fat diet (HFD), and human LO2 cells. RESULTS AZGP1 levels were significantly decreased in liver tissues of NAFLD patients and mice. AZGP1 knockdown was found to activate inflammation;enhance steatogenesis, including promoting lipogenesis [sterol regulatory elementbinding protein (SREBP)-1c, liver X receptor (LXR), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and stearoyl CoA desaturase 1 (SCD)-1], increasing lipid transport and accumulation [fatty acid transport protein (FATP), carnitine palmitoyl transferase (CPT)-1A, and adiponectin], and reducing fatty acid β-oxidation [farnesoid X receptor (FXR) and peroxisome proliferator-activated receptor (PPAR)-α];accelerate proliferation;and reverse apoptosis in LO2 cells. AZGP1 overexpression (OV-AZGP1) had the opposite effects. Furthermore, AZGP1 alleviated NAFLD by blocking TNF-α-mediated inflammation and intracellular lipid deposition, promoting proliferation, and inhibiting apoptosis in LO2 cells. Finally, treatment with OV-AZGP1 plasmid dramatically improved liver injury and eliminated liver fat in NAFLD mice. CONCLUSION AZGP1 attenuates NAFLD with regard to ameliorating inflammation, accelerating lipolysis, promoting proliferation, and reducing apoptosis by negatively regulating TNF-α. AZGP1 is suggested to be a novel promising therapeutic target for NAFLD.
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。
