AMP活化蛋白激酶研究进展

能量代谢失衡是肥胖、糖尿病及代谢综合征的主要原因.AMP活化蛋白激酶(AMPK)是一种重要的蛋白激酶,可以调节能量代谢,开启分解代谢途径,如脂肪酸氧化和糖酵解,从而增加ATP的产生,同时关闭合成代谢途径,如多种脂类、蛋白质及糖原的合成,减少ATP的消耗.在增加骨骼肌对匍萄糖的摄取、增强胰岛素敏感性、增加脂肪酸氧化以及调节基因转录等方面发挥重要作用.AMPK不仅町以在细胞水平作为"能量调节器",在整体水平还可以通过激素和细胞因子,如瘦素、脂联素和ghrelin调节机体的能量代谢.凼而,阐明AMPK在不同组织细胞及整体水平上调节糖脂代谢的机制是今后该领域的研究热点,也是临床治疗肥胖、2型糖尿病及代谢综合征等疾病的有效靶点.     

AMP活化蛋白激酶研究进展

能量代谢失衡是肥胖、糖尿病及代谢综合征的主要原因.AMP活化蛋白激酶(AMPK)是一种重要的蛋白激酶,可以调节能量代谢,开启分解代谢途径,如脂肪酸氧化和糖酵解,从而增加ATP的产生,同时关闭合成代谢途径,如多种脂类、蛋白质及糖原的合成,减少ATP的消耗.在增加骨骼肌对匍萄糖的摄取、增强胰岛素敏感性、增加脂肪酸氧化以及调节基因转录等方面发挥重要作用.AMPK不仅町以在细胞水平作为"能量调节器",在整体水平还可以通过激素和细胞因子,如瘦素、脂联素和ghrelin调节机体的能量代谢.凼而,阐明AMPK在不同组织细胞及整体水平上调节糖脂代谢的机制是今后该领域的研究热点,也是临床治疗肥胖、2型糖尿病及代谢综合征等疾病的有效靶点.     

AMP活化蛋白激酶研究进展

能量代谢失衡是肥胖、糖尿病及代谢综合征的主要原因.AMP活化蛋白激酶(AMPK)是一种重要的蛋白激酶,可以调节能量代谢,开启分解代谢途径,如脂肪酸氧化和糖酵解,从而增加ATP的产生,同时关闭合成代谢途径,如多种脂类、蛋白质及糖原的合成,减少ATP的消耗.在增加骨骼肌对匍萄糖的摄取、增强胰岛素敏感性、增加脂肪酸氧化以及调节基因转录等方面发挥重要作用.AMPK不仅町以在细胞水平作为"能量调节器",在整体水平还可以通过激素和细胞因子,如瘦素、脂联素和ghrelin调节机体的能量代谢.凼而,阐明AMPK在不同组织细胞及整体水平上调节糖脂代谢的机制是今后该领域的研究热点,也是临床治疗肥胖、2型糖尿病及代谢综合征等疾病的有效靶点.     

腺苷酸活化蛋白激酶对糖脂代谢的影响

腺苷酸活化蛋白激酶（AMPK）是一种重要的代谢应激蛋白激酶，在运动、缺氧等应激条件下可被高浓度的腺苷酸别构激活，AMPK一旦活化就可以使许多参与葡萄糖摄取和脂肪酸氧化的蛋白磷酸化，促进葡萄糖摄取，增加脂肪酸氧化，增加能量消耗，并且可以调控葡萄糖诱导基因的转录。5-氨基-4-甲酰胺噗唑核糖核苷酸（AICAR）是AMPK的非特异性激动剂，运动的急性效应（增加骨骼肌葡萄糖撮取）和慢性效应（增加葡萄糖转运子4）都可以被AICAR所重复。AMPK可能在2型糖尿病的运动治疗中发挥了重要作用。     

α-硫辛酸对糖尿病大鼠下丘脑和骨骼肌组织腺苷酸活化蛋白激酶表达及活性影响的研究

目的 观察α-辛酸对糖尿病大鼠腺苷酸活化蛋白激酶(AMPK)的影响,探讨其改善糖尿病代谢异常的作用.方法 将大鼠分为正常对照(NC)组、T2DM (T2DM)组、糖尿病α-硫辛酸干预(LA)组.Western blot检测下丘脑及骨骼肌组织AMPKα及ph-AMPKα蛋白的表达,RT-PCR测AMPKα mRNA表达.结果 与NC组比较,T2DM组骨骼肌、下丘脑内AMPK表达水平(21％和22％)及活性(37％和21％)降低(P＜0.05),血糖、血脂水平升高;与T2DM组比较,LA组骨骼肌内AMPK表达水平(20％)及活性(49％)升高(P＜0.05),而下丘脑内AMPK表达水平(17％)及活性(36％)降低(P＜0.05),血糖、血脂水平降低.结论 α-硫辛酸可激活骨骼肌AMPK,抑制下丘脑AMPK活性,可能是其改善糖脂代谢异常的部分机制.     

老年大鼠骨骼肌腺苷酸活化蛋白激酶对胰岛素敏感性的影响

胰岛素抵抗（insulin resistanse IR）是2型糖尿病的主要发病机制和心血管疾病的危险因素。随着年龄的增长,IR和2型糖尿病的发生呈增高趋势,但年龄相关的IR发生的确切机制仍不清楚。有研究表明,腺苷酸活化蛋白激酶（AMPK）通过使其下游酶的磷酸化,在提高脂肪酸氧化方面起了关键作用。我们于2006年10月至2007年2月观察了老年大鼠骨骼肌AMPKα表达和活性，探讨其在脂质堆积和IR中的作用。     

腺苷酸活化蛋白激酶与心血管疾病

1973年,Gobson和Carlson分别报道了腺苷酸活化蛋白激酶(adenosine monophosphate-activated protein kinase,AMPK)广泛存在真核细胞生物中,通过影响细胞物质代谢的多个环节来维持细胞能量供求平衡和调节细胞功能.细胞能量不足时会激活AMPK,一方面抑制糖原、脂肪和胆固醇的合成,减少ATP的利用;另一方面,促进脂肪酸氧化、葡萄糖转运等,增加ATP的产生.反之,当细胞内存在高浓度的ATP则可以抑制该效应.……     

卒中后腺苷酸活化蛋白激酶作用的研究进展

腺苷酸活化蛋白激酶(adenosine monophosphate-activated protein kinase,AMPK)是一种代谢和应激反应的感受器和效应器,在调节能量代谢和维持机体稳态中,发挥着重要的作用。当消耗细胞能量、提高AMP/三磷酸腺苷(adenosine triphosphate,ATP)比值的生理和病理刺激时,如营养缺乏、剧烈活动、热休克、代谢性酸中毒、氧化应激和缺血、缺氧等,均能激     

下丘脑腺苷酸活化蛋白激酶与食欲和体重调节

腺苷酸活化蛋白激酶（AMPK）也称为真核细胞的“能量感受器”，下丘脑AMPK活性的下调能使摄食减少、体重降低，反之，摄食、体重增加。下丘脑AMPK能整合ghrelin等刺激食欲的信号和胰岛素、睫状神经营养因子等抑制食欲的信号，可能处于食欲、体重调节的中心环节，其机制可能在于改变了神经肽Y、刺鼠相关蛋白等的表达。对AMPK结构的阐明及对此信号通路的深入研究可能为肥胖的治疗提供新的靶点。     

磷酸化腺苷酸活化蛋白激酶α在脂肪变性人肝癌HepG2细胞中的表达及其意义

目的观察腺苷酸活化蛋白激酶(AMPK)α磷酸化在Hep G2细胞脂变模型中的表达及意义。方法 Hep G2细胞予油酸和棕榈酸组成的0.3 mmol/L游离脂肪酸(FFA)诱导24 h后,建立脂肪变性Hep G2细胞模型,并设置对照组比较。诱导成功后,采用油红O染色观察细胞内脂滴蓄积状态;采用全自动生化仪检测细胞上清丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)含量和细胞内甘油三酯(TG)含量;采用生物试剂盒检测细胞内超氧化物歧化酶(SOD)和丙二醛(MDA)含量的变化,运用Western印迹法检测各组细胞AMPKα和磷酸化AMPKα(p AMPKα)蛋白的表达。结果与对照组比较,模型组细胞内橘红色脂滴大量形成,且细胞内TG和MDA含量明显升高(P0.01),SOD含量水平明显下降(P0.01),p AMPKα蛋白表达均显著降低(P0.01)。结论 FFA诱导的脂肪变性Hep G2细胞模型可以出现脂质代谢紊乱和氧化应激状态,其机制可能与细胞内p AMPKα蛋白的激活减少有关。     

Role of AMP-activated protein kinase gamma 3 genetic variability in glucose and lipid metabolism in non-diabetic whites

Aims/hypothesis AMP-activated protein kinase (AMPK) is a heterotrimeric enzyme that acts as an intracellular fuel sensor, directing multiple metabolic pathways in a catabolic direction in times of nutrient shortage. In humans, three different γ-subunits (γ₁, γ₂, γ₃) have been identified as AMPK regulators. The AMPKγ3 (protein kinase, AMP-activated, gamma 3 non-catalytic subunit, PRKAG3) isoform plays a role in gene regulation in glucose/lipid metabolism and skeletal muscle glycogen content. We investigated whether PRKAG3, in addition to being expressed in skeletal muscle, is also expressed in human liver. We also investigated whether genetic variance in PRKAG3 is associated with glucose and/or lipid metabolism in non-diabetic whites. Materials and methods After sequencing a screening cohort (n = 50) in the PRKAG3 locus, we genotyped 1061 participants for frequently found single nucleotide polymorphisms (SNPs). Association analyses between genotypes/haplotypes and metabolic traits were carried out. Results We detected PRKAG3 expression in human liver and skeletal muscle. Two SNPs (rs692243, rs6436094) with minor allele frequencies of 0.16 and 0.26 respectively and in moderate linkage disequilibrium (D′ = 0.92; r ² = 0.47) were found. rs692243 (C/G) confers a Pro71Ala mutation, while rs6436094 (A/G) is located in the 3′ untranslated region. No associations with prediabetic traits such as body fat distribution, insulin resistance or insulin secretion were found (p > 0.15 for all). However, the minor alleles of both SNPs were significantly associated with higher serum LDL-cholesterol and apolipoprotein (Apo) B-100 levels (rs692243: CG:LDL 4.3%, ApoB-100 3.4%; GG:LDL 7.6%, ApoB-100 5.4%; p = 0.008 and p = 0.01 respectively; rs6436094: AG:LDL 3.3%, ApoB-100 1.7%; GG:LDL 11.3%, ApoB-100 11.1%; p = 0.009 and p = 0.05 respectively; dominant model). The GG/GG diplotype homozygous for both minor SNP alleles displayed the highest LDL-cholesterol among all frequent diplotypes (p = 0.059). Conclusions/interpretation While genetic variability in PRKAG3 does not seem to have a major effect on glucose metabolism, it may play an important role in lipoprotein metabolism in humans.     

Apolipoprotein A-I stimulates AMP-activated protein kinase and improves glucose metabolism

Aims/hypothesis In humans, one of the hallmarks of type 2 diabetes is a reduced plasma concentration of HDL and its major protein component, apolipoprotein A-I (APOA-I). However, it is unknown whether APOA-I directly protects against diabetes. The aim of this study was to characterise the functional role of APOA-I in glucose homeostasis. Methods The effects of APOA-I on phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-coenzyme A carboxylase (ACC), glucose uptake and endocytosis were analysed in C2C12 myocytes. Glucose metabolism was investigated in Apoa-I knockout (Apoa-I ^−/−) mice. Results APOA-I was able to stimulate the phosphorylation of AMPK and ACC, and elevated glucose uptake in C2C12 myocytes. APOA-I could be endocytosed into C2C12 myotubes through a clathrin-dependent endocytotic process. Inhibition of endocytosis abrogated APOA-I-stimulated AMPK phosphorylation. In Apoa-I ^−/− mice, AMPK phosphorylation was reduced in skeletal muscle and liver, and expression of gluconeogenic enzymes was increased in liver. In addition, the Apoa-I ^−/− mice had increased fat content and compromised glucose tolerance. Conclusions/interpretation Our data indicate that APOA-I has a protective effect against diabetes via activation of AMPK. ApoA-I deletion in the mouse led to increased fat mass and impaired glucose tolerance.     

AMP-activated protein kinase: Role in metabolism and therapeutic implications

AMP-activated protein kinase (AMPK) is an enzyme that works as a fuel gauge which becomes activated in situations of energy consumption. AMPK functions to restore cellular ATP levels by modifying diverse metabolic and cellular pathways. In the skeletal muscle, AMPK is activated during exercise and is involved in contraction-stimulated glucose transport and fatty acid oxidation. In the heart, AMPK activity increases during ischaemia and functions to sustain ATP, cardiac function and myocardial viability. In the liver, AMPK inhibits the production of glucose, cholesterol and triglycerides and stimulates fatty acid oxidation. Recent studies have shown that AMPK is involved in the mechanism of action of metformin and thiazolidinediones, and the adipocytokines leptin and adiponectin. These data, along with evidence that pharmacological activation of AMPK in vivo improves blood glucose homeostasis, cholesterol concentrations and blood pressure in insulin-resistant rodents, make this enzyme an attractive pharmacological target for the treatment of type 2 diabetes, ischaemic heart disease and other metabolic diseases.     

单磷酸腺苷活化蛋白激酶与肾脏疾病

单磷酸腺苷活化蛋白激酶(AMPK)是体内一种重要的蛋白激酶,广泛分布于全身各组织器官,发挥不同的功能.AMPK作为“细胞能量调节器”来调节糖、脂代谢及蛋白质合成,并参与调控机体炎症反应和细胞增生等过程,参与多种疾病(如动脉粥样硬化、肿瘤、糖尿病和其他代谢性疾病)的发生发展.近年来随着研究的深入,AMPK与肾脏疾病的关系逐渐受到关注.     

AMPK-能量代谢感受器与可激活AMPK相关的药物研究进展

单磷酸腺苷活化蛋白激酶（AMPK）可以感受细胞能量代谢变化,调节细胞的葡萄糖、脂肪酸的代谢过程。AMPK与细胞生长、生存和多种代谢信号途径关系密切,研究发现AMPK信号途径涉及炎症、肿瘤和代谢疾病。本文综述AMPK的功能与炎症、肿瘤、代谢类疾病的关系和诸如水杨酸、二甲双胍等药物激活AMPK的研究进展。     

二甲双胍和饮食因素对糖尿病小鼠骨骼肌AMPK活性的影响

将2型糖尿病KK-Ay小鼠分为二甲双胍／高脂饮食、二甲双胍／低脂饮食、高脂饮食和低脂饮食4组，通过测定骨骼肌中腺苷酸活化蛋白激酶（AMPK）活性，发现二甲双胍和低脂饮食均可使AMPK活性增加，二者不存在累加效应。     

腺苷酸活化蛋白激酶与胰岛素抵抗

腺苷酸活化蛋白激酶（AMP-activated protein kinase, AMPK）是一类重要的蛋白激酶,通过改变细胞代谢和调节基因转录恢复细胞ATP水平。AMPK参与了肌肉收缩介导的葡萄糖转运和脂肪酸氧化,抑制肝脏葡萄糖、胆固醇和甘油三酯产生,并具有调节食物摄取和体重的作用。AMPK信号通路是目前具有吸引力的治疗肥胖、胰岛素抵抗、2型糖尿病和其它代谢病的药理靶点。     

脂联素通过LKB1途径激活腺苷酸活化蛋白激酶

目的 探讨脂联素是否通过LKB1途径激活骨骼肌及肝脏中腺苷酸活化蛋白激酶(AMPK).方法 将28只6周龄雄性Sprague-Dawley大鼠分为普通饮食组(NC组,n=15)和高脂饮食组(HF组,n=13).喂养16 周后,取空腹静脉血测定血清游离脂肪酸(FFA)、甘油三酯(TG)、总胆固醇(TC)、空腹血糖(FPG)、空腹胰岛素(FINS)及脂联素.采用Western印迹法测定各组大鼠骨骼肌及肝脏组织中AMPKα、磷酸化的AMPKcα和LKB1蛋白的表达.将原代培养的骨骼肌细胞及肝细胞分别予以脂联素和根赤壳菌素干预,免疫荧光技术测定各组细胞中AMPKα、磷酸化AMPKα和LKB1蛋白的表达.结果 与NC组比较,HF组大鼠体重、FFA、TG、FPG、FINS均升高(均P＜0.05),脂联素水平降低(P＜0.05).骨骼肌及肝组织巾AMPKα磷酸化和LKB1蛋白表达水平降低(均P＜0.05).原代培养大鼠骨骼肌细胞及肝细胞中脂联素显著增加AMPKα磷酸化及LKB1表达水平(均P＜0.05).加入根赤壳菌素表达明显降低(均P＜0.05).结论 脂联素在大鼠骨骼肌和肝脏组织可能通过LKB1途径激活AMPK.