AIM: To investigate the redox dependency and promotion of downstream targets in thyroid hormone (T<sub>3</sub>)-induced AMP-activated protein kinase (AMPK) signaling as cellular energy sensor to limit meta...AIM: To investigate the redox dependency and promotion of downstream targets in thyroid hormone (T<sub>3</sub>)-induced AMP-activated protein kinase (AMPK) signaling as cellular energy sensor to limit metabolic stresses in the liver.展开更多
Background:Metabolic stress has been proposed to contribute to neuronal damage in glaucoma,but the mechanism driving this response is not understood.The adenosine monophosphate-activated protein kinase(AMPK)is a maste...Background:Metabolic stress has been proposed to contribute to neuronal damage in glaucoma,but the mechanism driving this response is not understood.The adenosine monophosphate-activated protein kinase(AMPK)is a master regulator of energy homeostasis that becomes active at the onset of energy stress.AMPK is a potent inhibitor of the mammalian target of rapamycin complex 1(mTORC1),which we showed is essential for the maintenance of retinal ganglion cell(RGC)dendrites,synapses,and survival.Here,we tested the hypothesis that AMPK is an early mediator of metabolic stress in glaucoma.Methods:Unilateral elevation of intraocular pressure was induced by injection of magnetic microbeads into the anterior chamber of mice expressing yellow fluorescent protein in RGCs.Inhibition of AMPK was achieved by administration of siRNA or compound C.RGC dendritic trees were 3D-reconstructed and analyzed with Imaris(Bitplane),and survival was assessed by counting Brn3a or RBPMS-labeled soma and axons in the optic nerve.RGC function was examined by quantification of anterograde axonal transport after intraocular administration of cholera toxinβ-subunit.Retinas from glaucoma patients were analyzed for expression of active AMPK.Results:Ocular hypertension triggered rapid upregulation of AMPK activity in RGCs concomitant with loss of mTORC1 function.AMPK inhibition with compound C or siRNA effectively restored mTORC1 activity and promoted an increase in total dendritic length,surface and complexity relative to control retinas.Attenuation of AMPK activity led to robust RGC soma and axon survival.For example,95%of RGCs(2,983±258 RGCs/mm2,mean±S.E.M.)survived with compound C compared to 77%in vehicle-treated eyes(2,430±233 RGCs/mm2)(ANOVA,P<0.001)at three weeks after glaucoma induction(n=8-10/group).Importantly,blockade of AMPK activity effectively restored anterograde axonal transport.Lastly,RGC-specific upregulation of AMPK activity was detected in human glaucomatous retinas relative to age-matched controls(n=10/group).Conclusions:Metabolic stress in glaucoma involves AMPK activation and mTORC1 inhibition promoting early RGC dendritic pathology,dysfunction and neurodegeneration.展开更多
Obesity is a worldwide epidemic. Promoting browning of white adipose tissue(WAT)contributes to increased energy expenditure and hence counteracts obesity. Here we show that cordycepin(Cpn), a natural derivative of ade...Obesity is a worldwide epidemic. Promoting browning of white adipose tissue(WAT)contributes to increased energy expenditure and hence counteracts obesity. Here we show that cordycepin(Cpn), a natural derivative of adenosine, increases energy expenditure, inhibits weight gain, improves metabolic profile and glucose tolerance, decreases WAT mass and adipocyte size, and enhances cold tolerance in normal and high-fat diet-fed mice. Cpn markedly increases the surface temperature around the inguinal WAT and turns the inguinal fat browner. Further investigations show that Cpn induces the development of brown-like adipocytes in inguinal and, to a less degree, epididymal WAT depots. Cpn also increases the expression of uncoupling protein 1(UCP1) and other thermogenic genes in WAT and3T3-L1 differentiated adipocytes, in which AMP-activated protein kinase(AMPK) plays an important role. Our results provide novel insights into the function of Cpn in regulating energy balance, and suggest a potential utility of Cpn in the treatment of obesity.展开更多
多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸...多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)及哺乳动物雷帕霉素靶蛋白(Mammalian target of rapamycin,mTOR)作为细胞能量感受器是其中两个关键靶点。二者在PCOS各个发病部位包括下丘脑-垂体-卵巢轴、子宫内膜、脂肪与骨骼肌中发挥重要的调节作用,通过影响细胞自噬、氧化应激、炎症、线粒体功能、葡萄糖摄取等,促进卵泡的发育和成熟,改善胰岛素抵抗。近年来,中医药因其成分多样、靶点众多等优势广泛应用于临床,研究人员已对PCOS的发病以及中药治疗及改善PCOS的机制进行了大量研究,结果提示AMPK与mTOR相关通路在其中发挥关键作用。通过总结中药干预AMPK与mTOR及其相关通路治疗PCOS的研究结果,为临床治疗及基础研究提供参考。展开更多
Epidemiological studies indicate that treatment with metformin, an AMP-activated protein kinase (AMPK) activator, reduces the incidence of cancers. Activation of AMPK has also been reported to oppose tumor progression...Epidemiological studies indicate that treatment with metformin, an AMP-activated protein kinase (AMPK) activator, reduces the incidence of cancers. Activation of AMPK has also been reported to oppose tumor progression in diverse types of cancers and offers promising cancer therapy. Furthermore, AMPK is a primary regulator of energy metabolism and has also been implicated in cell cycle progression, angiogenesis, cell transformation, migration, and cancer. We have recently synthesized novel flavonoids, namely, triphenylmethanol derivatives (TPMs), but the effectiveness of the TPMs on the activity of AMPK remains unclear. We hypothesized that the novel TPMs would inhibit cancer cell proliferation through the activation of AMPK isoforms in cells. The effects of TPMs on prostate cells (PC-3) were investigated. Cells were exposed to TPMs for either 12 or 24 hr. at the respective doses of 0, 25, 50 100, and 200 µM based on the cell viability studies by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) (MTT) assay. The results indicate that cells exposed to the respective doses of TPMs increased both phospho- and total-AMPKα1 in a dose- and time-dependent manner. The effects of the increases for the phospho- and total-AMPKα in cells were greater for the 24-hr than the 12-hr. incubation. Further studies are currently going on to elucidate the specificities of the said insults in increasing the phospho- and total-AMPKα activities and for the other respective isoforms.展开更多
The AMP-activated protein kinase(AMPK)is a sensor of cellular energy status that is almost universally expressed in eukaryotic cells.While it appears to have evolved in single-celled eukaryotes to regulate energy bala...The AMP-activated protein kinase(AMPK)is a sensor of cellular energy status that is almost universally expressed in eukaryotic cells.While it appears to have evolved in single-celled eukaryotes to regulate energy balance in a cell-autonomous manner,during the evolution of multicellular animals its role has become adapted so that it also regulates energy balance at the whole body level,by responding to hormones that act primarily on the hypothalamus.AMPK monitors energy balance at the cellular level by sensing the ratios of AMP/ATP and ADP/ATP,and recent structural analyses of the AMPK heterotrimer that have provided insight into the complex mechanisms for these effects will be discussed.Given the central importance of energy balance in diseases that are major causes of morbidity or death in humans,such as type 2 diabetes,cancer and inflammatory disorders,there has been a major drive to develop pharmacological activators of AMPK.Many such activators have been described,and the various mechanisms by which these activate AMPK will be discussed.A particularly large class of AMPK activators are natural products of plants derived from traditional herbal medicines.While the mechanism by which most of these activate AMPK has not yet been addressed,I will argue that many of them may be defensive compounds produced by plants to deter infection by pathogens or grazing by insects or herbivores,and that many of them will turn out to be inhibitors of mitochondrial function.展开更多
Endothelial dysfunction is caused by many factors, such as dyslipidemia, endoplasmic reticulum(ER) stress, and inflammation.It has been demonstrated that endothelial dysfunction is the initial process of atheroscleros...Endothelial dysfunction is caused by many factors, such as dyslipidemia, endoplasmic reticulum(ER) stress, and inflammation.It has been demonstrated that endothelial dysfunction is the initial process of atherosclerosis. AMP-activated protein kinase(AMPK) is an important metabolic switch that plays a crucial role in lipid metabolism and inflammation. However, recent evidence indicates that AMPK could be a target for atherosclerosis by improving endothelial function. For instance, activation of AMPK inhibits the production of reactive oxygen species induced by mitochondrial dysfunction, ER stress, and NADPH oxidase. Moreover, activation of AMPK inhibits the production of pro-inflammatory factors induced by dyslipidemia and hyperglycemia and restrains production of perivascular adipose tissue-released adipokines. AMPK activation prevents endothelial dysfunction by increasing the bioavailability of nitric oxide. Therefore, we focused on the primary risk factors involved in endothelial dysfunction, and summarize the features of AMPK in the protection of endothelial function, by providing signaling pathways thought to be important in the pathological progress of risk factors.展开更多
OBJECTIVE: To assess the effect of a mixture of five herbal extracts(FT-5) on insulin resistance, glucose/lipid metabolism, hepatic steatosis, and to investigate whether the combination of FT-5 and pioglitazone would ...OBJECTIVE: To assess the effect of a mixture of five herbal extracts(FT-5) on insulin resistance, glucose/lipid metabolism, hepatic steatosis, and to investigate whether the combination of FT-5 and pioglitazone would provide a robust effect on diabetes treatment, while may minimize undesirable side-effects of pioglitazone in diabetic Ay gene(KKAy)mice.METHODS: Seven-week-old KKAy mice were randomly divided into five groups: control(CON)group, FT-5(2.0 g/kg) group, pioglitazone(20 mg/kg)(PIO) group, pioglitazone(20 mg/kg) + FT-5(2.0 g/kg)(P + F) group. Age-matched C57 BL/6 J micewere used as the control group. After seven weeks of continuous intragastric administration of medication, the glucose metabolism, insulin sensitivity and lipid metabolism of KKAy mice were evaluated by assessing the fasting blood glucose(FBG), oral glucose tolerance test(OGTT), fasting serum insulin(FINS), insulin tolerance test(ITT), homeostasis model of assessment-insulin resistance index(HOMA-IR), total cholesterol(TC), total triglycerides(TG), and free fatty acids(FFA) in plasma and liver.Plasma and hepatic adiponectin were measured via enzyme-linked immunosorbent assays. Genes related to adipogenesis and lipolysis in white adipose tissues(WAT) and liver were examined by real-time polymerase chain reaction. Lipid metabolism-related protein expression in the liver of KKAy mice were detected by Western blotting.RESULTS: PIO treatment remarkably improved insulin resistance. However, it also showed substantial side effects. FT-5 group exhibited no significant decrease in serum glucose. However, it reduced fasting plasma TG levels and improved hepatic steatosis of KKAy mice. P + F group showed improved insulin resistance and similar body weight gain, as compared with control group. The m RNA expression of genes related to fatty acid oxidation was markedly up-regulated in the liver of P + F group.Pioglitazone administration markedly decreased the phosphorylation levels of AMPK, as compared with all other groups. Besides, even though plasma adiponectin increased in PIO, FT-5, P + F group, adipo R2 gene expression significantly decreased in the liver of PIO group.CONCLUSION: FT-5 decreased plasma TG and alleviated aggravating hepatic steatosis induced by pioglitazone in KKAy mice. FT-5's mechanism might be associated with its ability to activate the Adipo R2/AMPK pathway.展开更多
Background Recent studies on bone have shown an endocrine role of the skeleton,which could be impaired in various human diseases,including osteoporosis,obesity,and diabetes-associated bone diseases.As a sensor and reg...Background Recent studies on bone have shown an endocrine role of the skeleton,which could be impaired in various human diseases,including osteoporosis,obesity,and diabetes-associated bone diseases.As a sensor and regulator of energy metabolism,AMP-activated protein kinase (AMPK) may also play an important role in the regulation of bone metabolism.The current study aimed to establish the expression profiles and phosphorylation patterns of AMPK subunits in several mesenchymal cell types.Methods Reverse transcription-polymerase chain reaction (PCR) for relative quantification,real-time PCR for absolute quantification,and Western blotting were used to investigate the gene expression profiles and phosphorylation patterns of AMPK subunits in several mesenchymal cell types,including primary human mesenchymal stem cells (hMSCs) and hFOB,Saos-2,C3H/10T1/2,MC3T3-E1,3T3-L1,and C2C12 cells.Results AMPKα1 and AMPKβ1 mRNAs were abundantly expressed in all cell types.AMPKY1 mRNA was abundantly expressed in C3H/10T1/2,MC3T3-E1,3T3-L1,and C2C12 but not detected in human-derived cell types.AMPKY2 mRNA was mildly expressed in all cell types.AMPKα1 protein was highly expressed in all cell types and AMPKα2 protein was highly expressed only in hFOB and Saos-2 cells.AMPKβ1 protein was abundantly expressed in all cell types except for Saos-2,in which AMPKβ2 protein overwhelmed AMPKβ1 expression.AMPKy1 and AMPKY2 proteins were expressed in C3H/10T1/2,MC3T3-E1,3T3-L1,and C2C12 cells and only AMPKY2 protein was expressed in hMSCs,hFOB and Saos2 cells.AMPKα was phosphorylated at Thr172 and Ser485 and AMPKβ1 was phosphorylated at Ser108 and Ser182 in all cell types with a specific pattern in each cell type.Conclusion The combination of AMPK α,β,and Y subunits and phosphorylation of AMPKα (Thr172 and Ser485) and AMPKβ1 (Ser108 and Ser182) showed a specific pattern in each cell type.展开更多
基金Supported by National Commission for Scientific and Technological Research Grant No.1120034
文摘AIM: To investigate the redox dependency and promotion of downstream targets in thyroid hormone (T<sub>3</sub>)-induced AMP-activated protein kinase (AMPK) signaling as cellular energy sensor to limit metabolic stresses in the liver.
文摘Background:Metabolic stress has been proposed to contribute to neuronal damage in glaucoma,but the mechanism driving this response is not understood.The adenosine monophosphate-activated protein kinase(AMPK)is a master regulator of energy homeostasis that becomes active at the onset of energy stress.AMPK is a potent inhibitor of the mammalian target of rapamycin complex 1(mTORC1),which we showed is essential for the maintenance of retinal ganglion cell(RGC)dendrites,synapses,and survival.Here,we tested the hypothesis that AMPK is an early mediator of metabolic stress in glaucoma.Methods:Unilateral elevation of intraocular pressure was induced by injection of magnetic microbeads into the anterior chamber of mice expressing yellow fluorescent protein in RGCs.Inhibition of AMPK was achieved by administration of siRNA or compound C.RGC dendritic trees were 3D-reconstructed and analyzed with Imaris(Bitplane),and survival was assessed by counting Brn3a or RBPMS-labeled soma and axons in the optic nerve.RGC function was examined by quantification of anterograde axonal transport after intraocular administration of cholera toxinβ-subunit.Retinas from glaucoma patients were analyzed for expression of active AMPK.Results:Ocular hypertension triggered rapid upregulation of AMPK activity in RGCs concomitant with loss of mTORC1 function.AMPK inhibition with compound C or siRNA effectively restored mTORC1 activity and promoted an increase in total dendritic length,surface and complexity relative to control retinas.Attenuation of AMPK activity led to robust RGC soma and axon survival.For example,95%of RGCs(2,983±258 RGCs/mm2,mean±S.E.M.)survived with compound C compared to 77%in vehicle-treated eyes(2,430±233 RGCs/mm2)(ANOVA,P<0.001)at three weeks after glaucoma induction(n=8-10/group).Importantly,blockade of AMPK activity effectively restored anterograde axonal transport.Lastly,RGC-specific upregulation of AMPK activity was detected in human glaucomatous retinas relative to age-matched controls(n=10/group).Conclusions:Metabolic stress in glaucoma involves AMPK activation and mTORC1 inhibition promoting early RGC dendritic pathology,dysfunction and neurodegeneration.
基金supported financially by the National Natural Science Foundation of China (81402983, 81573436)CAMS Innovation Fund for Medical Sciences (CIFMS) 2016-I2M-3–015the National Major Scientific and Technological Special Project for "Significant New Drugs Development" (2015ZX09501005, China)
文摘Obesity is a worldwide epidemic. Promoting browning of white adipose tissue(WAT)contributes to increased energy expenditure and hence counteracts obesity. Here we show that cordycepin(Cpn), a natural derivative of adenosine, increases energy expenditure, inhibits weight gain, improves metabolic profile and glucose tolerance, decreases WAT mass and adipocyte size, and enhances cold tolerance in normal and high-fat diet-fed mice. Cpn markedly increases the surface temperature around the inguinal WAT and turns the inguinal fat browner. Further investigations show that Cpn induces the development of brown-like adipocytes in inguinal and, to a less degree, epididymal WAT depots. Cpn also increases the expression of uncoupling protein 1(UCP1) and other thermogenic genes in WAT and3T3-L1 differentiated adipocytes, in which AMP-activated protein kinase(AMPK) plays an important role. Our results provide novel insights into the function of Cpn in regulating energy balance, and suggest a potential utility of Cpn in the treatment of obesity.
文摘多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)及哺乳动物雷帕霉素靶蛋白(Mammalian target of rapamycin,mTOR)作为细胞能量感受器是其中两个关键靶点。二者在PCOS各个发病部位包括下丘脑-垂体-卵巢轴、子宫内膜、脂肪与骨骼肌中发挥重要的调节作用,通过影响细胞自噬、氧化应激、炎症、线粒体功能、葡萄糖摄取等,促进卵泡的发育和成熟,改善胰岛素抵抗。近年来,中医药因其成分多样、靶点众多等优势广泛应用于临床,研究人员已对PCOS的发病以及中药治疗及改善PCOS的机制进行了大量研究,结果提示AMPK与mTOR相关通路在其中发挥关键作用。通过总结中药干预AMPK与mTOR及其相关通路治疗PCOS的研究结果,为临床治疗及基础研究提供参考。
文摘Epidemiological studies indicate that treatment with metformin, an AMP-activated protein kinase (AMPK) activator, reduces the incidence of cancers. Activation of AMPK has also been reported to oppose tumor progression in diverse types of cancers and offers promising cancer therapy. Furthermore, AMPK is a primary regulator of energy metabolism and has also been implicated in cell cycle progression, angiogenesis, cell transformation, migration, and cancer. We have recently synthesized novel flavonoids, namely, triphenylmethanol derivatives (TPMs), but the effectiveness of the TPMs on the activity of AMPK remains unclear. We hypothesized that the novel TPMs would inhibit cancer cell proliferation through the activation of AMPK isoforms in cells. The effects of TPMs on prostate cells (PC-3) were investigated. Cells were exposed to TPMs for either 12 or 24 hr. at the respective doses of 0, 25, 50 100, and 200 µM based on the cell viability studies by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) (MTT) assay. The results indicate that cells exposed to the respective doses of TPMs increased both phospho- and total-AMPKα1 in a dose- and time-dependent manner. The effects of the increases for the phospho- and total-AMPKα in cells were greater for the 24-hr than the 12-hr. incubation. Further studies are currently going on to elucidate the specificities of the said insults in increasing the phospho- and total-AMPKα activities and for the other respective isoforms.
基金funded by a Senior Investigator Award(No.097726)from the Wellcome Trusta programme grant(No.C37030/A15101)from Cancer Research UK
文摘The AMP-activated protein kinase(AMPK)is a sensor of cellular energy status that is almost universally expressed in eukaryotic cells.While it appears to have evolved in single-celled eukaryotes to regulate energy balance in a cell-autonomous manner,during the evolution of multicellular animals its role has become adapted so that it also regulates energy balance at the whole body level,by responding to hormones that act primarily on the hypothalamus.AMPK monitors energy balance at the cellular level by sensing the ratios of AMP/ATP and ADP/ATP,and recent structural analyses of the AMPK heterotrimer that have provided insight into the complex mechanisms for these effects will be discussed.Given the central importance of energy balance in diseases that are major causes of morbidity or death in humans,such as type 2 diabetes,cancer and inflammatory disorders,there has been a major drive to develop pharmacological activators of AMPK.Many such activators have been described,and the various mechanisms by which these activate AMPK will be discussed.A particularly large class of AMPK activators are natural products of plants derived from traditional herbal medicines.While the mechanism by which most of these activate AMPK has not yet been addressed,I will argue that many of them may be defensive compounds produced by plants to deter infection by pathogens or grazing by insects or herbivores,and that many of them will turn out to be inhibitors of mitochondrial function.
基金supported by National Natural Science Foundation of China (91539126)the National Science and Technology Major Project (2017ZX09101003-003-011)CAMS Innovation Fund for Medical Sciences (2016-I2M-1-009)
文摘Endothelial dysfunction is caused by many factors, such as dyslipidemia, endoplasmic reticulum(ER) stress, and inflammation.It has been demonstrated that endothelial dysfunction is the initial process of atherosclerosis. AMP-activated protein kinase(AMPK) is an important metabolic switch that plays a crucial role in lipid metabolism and inflammation. However, recent evidence indicates that AMPK could be a target for atherosclerosis by improving endothelial function. For instance, activation of AMPK inhibits the production of reactive oxygen species induced by mitochondrial dysfunction, ER stress, and NADPH oxidase. Moreover, activation of AMPK inhibits the production of pro-inflammatory factors induced by dyslipidemia and hyperglycemia and restrains production of perivascular adipose tissue-released adipokines. AMPK activation prevents endothelial dysfunction by increasing the bioavailability of nitric oxide. Therefore, we focused on the primary risk factors involved in endothelial dysfunction, and summarize the features of AMPK in the protection of endothelial function, by providing signaling pathways thought to be important in the pathological progress of risk factors.
基金Supported by the Science and Technology Support Program of China(No.2014BAI10B04)
文摘OBJECTIVE: To assess the effect of a mixture of five herbal extracts(FT-5) on insulin resistance, glucose/lipid metabolism, hepatic steatosis, and to investigate whether the combination of FT-5 and pioglitazone would provide a robust effect on diabetes treatment, while may minimize undesirable side-effects of pioglitazone in diabetic Ay gene(KKAy)mice.METHODS: Seven-week-old KKAy mice were randomly divided into five groups: control(CON)group, FT-5(2.0 g/kg) group, pioglitazone(20 mg/kg)(PIO) group, pioglitazone(20 mg/kg) + FT-5(2.0 g/kg)(P + F) group. Age-matched C57 BL/6 J micewere used as the control group. After seven weeks of continuous intragastric administration of medication, the glucose metabolism, insulin sensitivity and lipid metabolism of KKAy mice were evaluated by assessing the fasting blood glucose(FBG), oral glucose tolerance test(OGTT), fasting serum insulin(FINS), insulin tolerance test(ITT), homeostasis model of assessment-insulin resistance index(HOMA-IR), total cholesterol(TC), total triglycerides(TG), and free fatty acids(FFA) in plasma and liver.Plasma and hepatic adiponectin were measured via enzyme-linked immunosorbent assays. Genes related to adipogenesis and lipolysis in white adipose tissues(WAT) and liver were examined by real-time polymerase chain reaction. Lipid metabolism-related protein expression in the liver of KKAy mice were detected by Western blotting.RESULTS: PIO treatment remarkably improved insulin resistance. However, it also showed substantial side effects. FT-5 group exhibited no significant decrease in serum glucose. However, it reduced fasting plasma TG levels and improved hepatic steatosis of KKAy mice. P + F group showed improved insulin resistance and similar body weight gain, as compared with control group. The m RNA expression of genes related to fatty acid oxidation was markedly up-regulated in the liver of P + F group.Pioglitazone administration markedly decreased the phosphorylation levels of AMPK, as compared with all other groups. Besides, even though plasma adiponectin increased in PIO, FT-5, P + F group, adipo R2 gene expression significantly decreased in the liver of PIO group.CONCLUSION: FT-5 decreased plasma TG and alleviated aggravating hepatic steatosis induced by pioglitazone in KKAy mice. FT-5's mechanism might be associated with its ability to activate the Adipo R2/AMPK pathway.
基金This study was supported by grants from the National Natural Science Foundation of China (No. 81000778, 81370050, and 81172549) and the Scientific Research and Innovation of Shanghai Municipal Education Commission (No. 11YZ46).
文摘Background Recent studies on bone have shown an endocrine role of the skeleton,which could be impaired in various human diseases,including osteoporosis,obesity,and diabetes-associated bone diseases.As a sensor and regulator of energy metabolism,AMP-activated protein kinase (AMPK) may also play an important role in the regulation of bone metabolism.The current study aimed to establish the expression profiles and phosphorylation patterns of AMPK subunits in several mesenchymal cell types.Methods Reverse transcription-polymerase chain reaction (PCR) for relative quantification,real-time PCR for absolute quantification,and Western blotting were used to investigate the gene expression profiles and phosphorylation patterns of AMPK subunits in several mesenchymal cell types,including primary human mesenchymal stem cells (hMSCs) and hFOB,Saos-2,C3H/10T1/2,MC3T3-E1,3T3-L1,and C2C12 cells.Results AMPKα1 and AMPKβ1 mRNAs were abundantly expressed in all cell types.AMPKY1 mRNA was abundantly expressed in C3H/10T1/2,MC3T3-E1,3T3-L1,and C2C12 but not detected in human-derived cell types.AMPKY2 mRNA was mildly expressed in all cell types.AMPKα1 protein was highly expressed in all cell types and AMPKα2 protein was highly expressed only in hFOB and Saos-2 cells.AMPKβ1 protein was abundantly expressed in all cell types except for Saos-2,in which AMPKβ2 protein overwhelmed AMPKβ1 expression.AMPKy1 and AMPKY2 proteins were expressed in C3H/10T1/2,MC3T3-E1,3T3-L1,and C2C12 cells and only AMPKY2 protein was expressed in hMSCs,hFOB and Saos2 cells.AMPKα was phosphorylated at Thr172 and Ser485 and AMPKβ1 was phosphorylated at Ser108 and Ser182 in all cell types with a specific pattern in each cell type.Conclusion The combination of AMPK α,β,and Y subunits and phosphorylation of AMPKα (Thr172 and Ser485) and AMPKβ1 (Ser108 and Ser182) showed a specific pattern in each cell type.