基于SIRT1/AMPK/SREBP-1c通路探讨加味二陈汤对非酒精性脂肪性肝病小鼠肝脏脂质代谢的影响

目的探讨加味二陈汤对非酒精性脂肪性肝病(NAFLD)小鼠肝脏脂质代谢的影响及机制。方法将40只C57BL/6小鼠随机分为正常组、模型组、阿托伐他汀组(0.05 g·kg^(-1))及加味二陈汤低、高剂量组(12、24 g·kg^(-1))。采用连续10周高脂饲料饲养复制NAFLD小鼠模型。从第11周开始灌胃给药(10 mL·kg^(-1)),每日1次,连续给药6周。第16周结束给药前,小鼠禁食12 h后腹腔注射1 g·kg^(-1)葡萄糖溶液,于0、15、30、60、90、120 min测定小鼠血糖值。测定并记录各组小鼠体质量、肝脏质量,计算肝脏系数;检测血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、谷草转氨酶(AST)、谷丙转氨酶(ALT)、超氧化物歧化酶(SOD)、总谷胱甘肽(TGSH)及肝脏组织TC、TG的含量或活性。采用HE染色法及油红O染色法观察肝组织病理变化;采用RT-qPCR及Western Blot法检测肝组织沉默信息调节因子1(SIRT1)、腺苷酸活化蛋白激酶(AMPK)及甾醇调节元件结合蛋白1c(SREBP-1c)mRNA及蛋白表达情况。结果造模结束后,与正常组比较,各造模组小鼠体质量显著升高(P<0.01,P<0.001)。给药结束后,与正常组比较,模型组小鼠的体质量、肝质量及肝脏系数显著升高(P<0.05,P<0.001);血清TC、TG及LDL-C水平显著升高(P<0.001),HDL-C水平显著降低(P<0.001);肝组织TC、TG及血清ALT、AST水平显著升高(P<0.05,P<0.001);血清SOD、TGSH水平显著降低(P<0.05,P<0.001),空腹及注射葡萄糖后(15、30、60、90、120 min)的血糖水平明显升高(P<0.05,P<0.01);肝组织细胞质可见大量的空泡,胞质出现大量红染的脂滴;肝组织SIRT1、AMPK mRNA及蛋白表达显著下调(P<0.01),SREBP-1c mRNA及蛋白表达显著上调(P<0.01,P<0.001)。与模型组比较,阿托伐他汀组及加味二陈汤低、高剂量组小鼠的体质量、肝质量、肝脏系数显著降低(P<0.05,P<0.01,P<0.001);血清TC、TG及LDL-C水平显著降低(P<0.05,P<0.01,P<0.001),HDL-C水平显著升高(P<0.001);肝组织TC、TG及血清ALT、AST水平显著降低(P<0.05,P<0.01,P<0.001);血清SOD、TGSH水平明显升高(P<0.05,P<0.01),空腹及注射葡萄糖后(15、30、60、90、120 min)的血糖水平明显降低(P<0.05,P<0.01);肝细胞胞质内橘红色脂滴显著减少,脂质蓄积显著改善;肝组织SIRT1、AMPK mRNA及蛋白表达显著上调(P<0.05,P<0.01,P<0.001),SREBP-1c mRNA及蛋白表达显著下调(P<0.01,P<0.001)。结论加味二陈汤对NAFLD小鼠肝脏脂质代谢有显著改善作用,其机制可能与调控SIRT1/AMPK/SREBP-1c通路有关。

Effect and Mechanism of Dicliptera chinensis Polysaccharide on miR-141/AMPK/SIRT1 Signaling Pathway in Rats with NAFLD

[Objectives]Non-alcoholic fatty liver disease(NAFLD)rat model was established by feeding high-fat and high-sugar fodder to rats,and the protective effect of Dicliptera chinensis polysaccharide(DCP)on NAFLD rats was studied to explore its potential mechanism.[Methods]45 SD rats were randomly divided into 4 groups:normal control group,model control group and DCP treatment groups(100 and 300 mg/kg).The rats in the normal control group were fed with ordinary fodder,and the rats in other groups were fed with high-fat and high-sugar diet for 14 weeks to establish NAFLD model.From the 9^(th)week,the rats in the DCP treatment groups were given different doses of DCP by intragastric administration(5 mL/kg)for 6 weeks.After the last intragastric administration,the rats fasted for 16 h,and the serum and liver of rats were collected for detection.Hematoxylin-eosin(HE)staining was conducted to observe the histopathological changes of rat liver,and alanine aminotransferase(ALT),aspartate aminotransferase(AST),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA),triglyceride(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),and high density lipoprotein cholesterol(HDL-C)were detected by biochemical method.Interleukin-6(IL-6),interleukin-1β(IL-1β),tumor necrosis factor(TNF-α)and micrornA-141(micro RNA-141)were detected by reverse transcription-polymerase chain reaction(RT-PCR).The expression of SIRT1 and adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)in rat liver was detected by western blot.[Results]Compared with the model control group,the inflammatory damage and steatodegeneration of rats in the DCP groups were relieved to varying degrees,and the number of lipid vacuoles significantly reduced.The ALT,AST,TC,TG and LDL-C content in the serum and MDA content in the liver tissue decreased to varying degrees,while the HDL-C,SOD and GSH-Px content increased.The expression of SIRT1 and AMPK increased,while the expression of miR-141,TNF-α,IL-6 and IL-1βdeclined,and the DCP 300 mg/kg treatment group had better improvement effect.[Conclusions]DCP had a certain protective effect on NAFLD rats,which may be related to the regulation of miR-141/AMPK/SIRT1 signaling pathway.

中药复方益糖康对2型糖尿病大鼠肝脏AMPK/SREBP-1C/FAS的影响

目的 通过观察中药复方益糖康对2型糖尿病大鼠血脂水平、肝脏形态学变化及肝脏中单磷酸腺苷活化的蛋白激酶(AMP-activated protein kinase, AMPK)/固醇调节元件结合蛋白1C(sterol regulatory element binding protein 1C,SREBP-1C)/脂肪酸合成酶(fatty acid synthetase, FAS) mRNA与蛋白表达的影响,探究益糖康对2型糖尿病大鼠脂代谢的干预作用及机制。方法 SPF级Wistar大鼠32只,随机选取8只为正常对照组予正常饲料喂养,其余大鼠予高脂饲料喂养。4周后,高脂喂养的大鼠予链脲佐菌素(streptozocin, STZ)腹腔注射造模,并随机分为模型组、益糖康组与二甲双胍组(n=8),正常对照组大鼠腹腔注射等量缓冲溶液。益糖康组与二甲双胍组分别予相应药物日1次灌胃治疗,正常对照组与模型组大鼠同期给予等体积生理盐水灌胃。给药6周后,检测大鼠血清总胆固醇(total cholesterol, TC)、甘油三酯(triglyceride, TG)、高密度脂蛋白胆固醇(high-density lipoproteincholesterol, HDL-C)、低密度脂蛋白胆固醇(low-density lipoprotein cholesterol, LDL-C)水平以及空腹血糖(fasting blood glucose, FBG)和空腹胰岛素(fasting insulin, FINS)水平,HE与油红O染色观测大鼠肝脏形态学变化与脂质沉积情况,RT-qPCR与Western blot分别检测AMPK/SREBP-1C/FAS mRNA与蛋白的表达情况。结果 与正常对照组相比,模型组大鼠肝脏可见脂肪空泡与炎性细胞浸润,油红着色脂滴沉积,血清FBG、FINS、TC、TG与LDL-C水平显著升高,HDL-C水平显著下降(P<0.01);肝脏AMPK mRNA与蛋白表达显著降低,SREBP-1C、FAS mRNA与蛋白表达显著升高(P<0.05,P<0.01);与模型组相比,益糖康、二甲双胍组肝脏脂肪空泡与炎性细胞浸润减轻,油红着色脂滴减少,血清FBG、FINS、TC、TG与LDL-C水平显著降低,HDL-C水平显著升高(P<0.05,P<0.01);肝脏AMPK mRNA与蛋白表达显著升高,SREBP-1C、FAS mRNA与蛋白表达显著降低(P<0.05,P<0.01)。结论 中药复方益糖康可能通过调控脂代谢相关通路AMPK/SREBP-1C/FAS,上调AMPK,下调SREBP-1C/FAS mRNA与蛋白表达改善2型糖尿病大鼠脂代谢紊乱。

基于AMPK/SREBP-1c通路探讨降糖三黄片防治2型糖尿病合并非酒精性脂肪肝的作用机制

【目的】观察降糖三黄片(由桃仁、大黄、芒硝、桂枝等组成)对2型糖尿病(T2DM)合并非酒精性脂肪肝(NAFLD)大鼠糖脂代谢、胰岛素抵抗、肝脏组织病理和腺苷酸活化蛋白激酶(AMPK)/甾醇调节元件结合蛋白1c(SREBP-1c)通路蛋白表达的影响。【方法】将30只SD大鼠随机分成空白对照组6只和造模组24只。采用高糖高脂饮食结合链脲佐菌素(STZ)一次性腹腔注射建立T2DM合并NAFLD大鼠模型。造模成功后,再将成模大鼠随机分成模型组、二甲双胍组(0.2 g·kg^(-1)·d^(-1))、降糖三黄片低剂量组(0.675 g·kg^(-1)·d^(-1))、降糖三黄片高剂量组(2.7 g·kg^(-1)·d^(-1)),每组6只。灌胃治疗4周后,检测糖脂代谢指标空腹血糖(FBG)、甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、游离脂肪酸(FFA)及空腹胰岛素(FINS),并计算胰岛素抵抗指数(HOMA-IR),检测肝功能指标谷草转氨酶(AST)、谷丙转氨酶(ALT),炎症因子白细胞介素(IL)-6、肿瘤坏死因子(TNF)-α、IL-1β,苏木素-伊红(HE)染色及油红O染色法观察肝脏组织形态变化,蛋白免疫印迹(Western Blot)法检测肝组织AMPK/SREBP-1c信号通路相关蛋白的表达。【结果】与空白对照组比较,模型组血清FBG、TG、TC、LDL-C、FFA水平升高,HDL-C水平降低,FINS、HOMA-IR水平升高,AST、ALT水平升高,IL-6、TNF-α、IL-1β水平升高,差异均有统计学意义(P<0.01或P<0.001),肝脏明显脂肪变,肝脏组织AMPK、SREBP-1c表达水平显著升高及p-AMPK表达水平下降(P<0.01或P<0.001);与模型组比较,降糖三黄片高剂量组的FBG、TG、TC、LDL-C水平降低,HDL-C水平升高,FINS和HOMA-IR水平降低,AST、ALT水平降低,IL-6、TNF-α、IL-1β水平降低,差异均有统计学意义(P<0.05或P<0.01或P<0.001),肝脏脂肪变现象明显改善,p-AMPK、SREBP-1c在肝脏内的表达水平得到改善(P<0.001);与二甲双胍组比较,降糖三黄片高剂量组的FBG、TG、TC、LDL-C、HDL-C、FFA,FINS、HOMA-IR,AST、ALT,IL-6、TNF-α、IL-1β、SREBP-1c水平均无显著性差异(P>0.05)。【结论】降糖三黄片可有效治疗T2DM合并NAFLD大鼠,其作用机制可能与通过调节AMPK-SREBP-1c途径减少大鼠肝脏脂质蓄积,进而提高胰岛素敏感性,改善肝脏代谢有关。

黄芪总皂苷配伍荷叶总生物碱对高脂血症大鼠肝脏AMPK/SREBP-1c/ACC通路的影响

目的 探讨黄芪总皂苷配伍荷叶总生物碱对高脂血症大鼠的防治作用及机制。方法 将60只SD雄性大鼠随机分为正常组、模型组、阳性药(辛伐他汀,2.1 mg·kg^(-1))组和黄芪总皂苷+荷叶总生物碱低(17+40 mg·kg^(-1))、中(34+80 mg·kg^(-1))、高(68+160 mg·kg^(-1))剂量组;采用高脂饲料喂养复制高脂血症大鼠模型,同时给予药物灌胃治疗,每日1次,连续4周。检测大鼠血清总胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(FFA)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、天门冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)水平;采用HE染色法观察肝脏组织病理形态学变化;qRT-PCR法检测肝组织中腺苷酸活化蛋白激酶(AMPK)、固醇调节元件结合蛋白1c(SREBP-1c)、乙酰辅酶A羧化酶(ACC)、肉碱棕榈酰转移酶1(CPT-1)m RNA表达情况;免疫荧光法检测肝组织中p-AMPK、SREBP-1c、ACC、CPT-1蛋白表达情况;Western Blot法检测肝组织中AMPK、p-AMPK、SREBP-1c、ACC、p-ACC、CPT-1蛋白表达情况。结果 与正常组比较,模型组大鼠血清TG、TC、FFA、LDL-C、AST、ALT水平显著升高(P<0.01),HDL-C水平显著下降(P<0.01);大鼠肝细胞内有大量的脂滴聚集,胞浆疏松,出现了大量脂滴空泡和气球样变,细胞核偏移;大鼠肝组织AMPK、CPT-1 mRNA表达显著下调(P<0.01),ACC、SREBP-1c mRNA表达显著上调(P<0.01);大鼠肝脏中p-AMPK、CPT-1蛋白阳性表达明显减少(P<0.05,P<0.01),SREBP-1c、ACC蛋白阳性表达显著增加(P<0.01);大鼠肝组织中AMPK蛋白表达未见明显变化(P>0.05),p-AMPK、p-ACC、CPT-1蛋白表达水平明显下降(P<0.01),SREBP-1c、ACC蛋白表达水平显著升高(P<0.01)。与模型组比较,各给药组大鼠血清TG、TC、FFA、LDL-C、AST、ALT水平明显下降(P<0.05,P<0.01),HDL-C水平明显升高(P<0.01);大鼠肝细胞内的脂肪沉积均有明显减轻,仅见少量的脂滴空泡;大鼠肝组织AMPK、CPT-1mRNA的表达明显上调(P<0.05,P<0.01),SREBP-1c、ACC mRNA表达明显下调(P<0.05,P<0.01);大鼠肝脏中p-AMPK、CPT-1蛋白阳性表达明显增加(P<0.05,P<0.01),SREBP-1c、ACC蛋白阳性表达显著减少(P<0.01);大鼠肝组织中AMPK蛋白表达未见明显变化(P>0.05),p-AMPK、p-ACC、CPT-1蛋白表达水平均明显升高(P<0.05,P<0.01),SREBP-1c、ACC蛋白表达水平显著降低(P<0.01)。结论 黄芪总皂苷配伍荷叶总生物碱可能通过调节AMPK/SREBP-1c/ACC信号通路,抑制脂肪合成,促进脂肪酸氧化分解来防治高脂血症。

黄芪散有效部位群对Ⅱ型糖尿病大鼠肝脏AMPK/SREBP-1c通路的影响

目的观察黄芪散有效部位群(HQS)对Ⅱ型糖尿病(T2DM)大鼠肝脏单磷酸腺苷活化蛋白激酶/固醇调控元件结合蛋白-1c(AMPK/SREBP-1c)通路的影响。方法采用低剂量链脲佐菌素(STZ)腹腔注射联合高脂饲料喂养建立T2DM大鼠模型,造模同时给予HQS(2.4 g·kg^(-1))灌胃给药,连续16周。测定大鼠血浆总胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(NEFA)及肝脏TC、TG含量;HE、油红O染色法观察肝脏病理变化;Western Blot法检测肝组织中AMPK(Thr172)、乙酰辅酶A羧化酶1(ACC1)(Ser79)、SREBP-1c(Ser372)、胰岛素受体底物-2(IRS-2)(Ser731)、蛋白激酶B(Akt)(Ser473)磷酸化蛋白以及AMPKα、SREBP-1c核蛋白(nSREBP-1c)、ACC1、脂肪酸合成酶(FAS)、IRS-2、Akt蛋白的表达;qPCR法检测肝组织中SREBP-1c、ACC1、FAS、硬脂酰辅酶A去饱和酶(SCD1)、IRS-2、Akt mRNA的表达。结果与正常组比较,模型组大鼠血浆TC、TG、NEFA及肝脏TC、TG水平均显著升高(P <0.05);肝组织存在明显的脂肪变性;p-SREBP-1c、IRS-2蛋白的表达和p-AMPK/AMPKα、p-ACC1/ACC1、p-Akt/Akt比值显著降低(P <0.05,P <0.01),AMPKα、n SREBP-1c、ACC1、FAS蛋白表达和p-IRS-2/IRS-2比值显著升高(P <0.05,P <0.01);SREBP-1c、ACC1、FAS、SCD1 mRNA表达水平明显上调(P <0.05,P <0.01),IRS-2、Akt mRNA表达下降(P <0.05)。与模型组比较,HQS组大鼠血浆TC、TG、NEFA及肝脏TC、TG水平显著降低(P <0.05);肝组织脂肪变性明显减轻;p-SREBP-1c、IRS-2蛋白表达和p-AMPK/AMPKα、p-ACC1/ACC1、p-Akt/Akt比值显著升高(P <0.05,P <0.01),nSREBP-1c、ACC1、FAS蛋白表达和p-IRS-2/IRS-2比值显著降低(P <0.05,P <0.01);SREBP-1c、ACC1、FAS、SCD1 mRNA表达水平明显下调(P <0.05),IRS-2 mRNA表达显著上调(P <0.05)。结论 HQS可能通过调节AMPK/SREBP-1c通路,减少脂质合成,改善T2DM大鼠肝脏胰岛素抵抗。

CHANGES IN NEUROPEPTIDES AFTER MUSIC EXPOSURE 429Cardioprotective effect of ivabradine via the AMPK/SIRT1/PGC-1αsignaling pathway in myocardial ischemia/reperfusion injuryinduced in H9c2 cell

Post-resuscitation myocardial dysfunction(PRMD)is the most severe myocardial ischemia-reperfusion injury(MIRI)and is characterized by difficult treatment and poor prognosis.Research has shown the protective effects of the rational use of ivabradine(IVA)against PRMD,however,the molecular mechanisms of IVA remain unknown.In this study,an ischemia-reperfusion injury(IRI)model was established using hypoxic chambers.The results demonstrated that pretreatment with IVA reduced IRI-induced cytotoxicity and apoptosis.IVA attenuated mitochondrial damage,eliminated excess reactive oxygen species(ROS),suppressed IRI-induced ATP and NAD+,and increased the AMP/ATP ratio.We further found that IVA increased the mRNA levels of sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α)and upregulated the expression levels of phosphorylated AMP-activated protein kinase(p-AMPK)/AMPK,SIRT1,and PGC-1αproteins.Interestingly,no change in AMPK mRNA levels was observed.Cardiomyocyte energy metabolism significantly changed after IRI.The aim of this study was to demonstrate the cardioprotective effect of Ivabradine via the AMPK/SIRT1/PGC-1αsignaling pathway in myocardial ischemia/reperfusion injury-induced in H9c2 cell.

基于AMPK/SREBP-1c信号通路探讨益气健脾汤对非酒精性脂肪性肝病小鼠糖脂代谢的影响

目的探讨益气健脾汤对非酒精性脂肪性肝病小鼠腺苷单磷酸活化蛋白激酶(AMPK)/固醇调节元件结合蛋白-1c(SREBP-1c)信号通路的影响。方法将40只C57BL/6J小鼠随机分为空白组、模型组、二甲双胍组、益气健脾汤组,每组10只。除空白组外,其他组均使用高脂饮食喂养建立非酒精性脂肪性肝病模型,造模周期为12周,从第9周开始,二甲双胍组给予二甲双胍100 mg/(kg·d)灌胃,益气健脾汤组给予益气健脾汤0.5 mL/d(生药浓度2.34 g/mL)灌胃,空白组和模型组给予蒸馏水0.5 mL/d灌胃。灌胃4周后,经腹主动脉采血,ELISA法检测血脂指标[三酰甘油(TG)、总胆固醇(TC)、游离脂肪酸(FFA)]、肝功能指标[丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)]、空腹血糖(FPG)、空腹胰岛素(FINS)水平,计算胰岛素抵抗指数(HOMA-IR);取肝脏,计算肝指数,使用HE染色和油红O染色观察肝脏组织病理学改变,分别采用Western blot法和RT-qPCR法检测肝组织中p-AMPK、SREBP-1c蛋白及mRNA表达情况。结果模型组小鼠血清TG、TC、FFA、ALT、AST、FPG、FINS水平及HOMA-IR、肝指数、NAS评分和油红O染色面积均明显高于空白组(P均<0.05),二甲双胍组和益气健脾汤组各指标均明显低于模型组(P<0.05)。HE染色及油红O染色显示,模型组小鼠肝组织可见肝细胞明显肿胀、气球样变性,大泡样脂滴形成并融合;二甲双胍组和益气健脾汤组肝细胞肿胀、气球样病变、脂肪变性均较模型组轻。各组小鼠肝组织中AMPK蛋白和mRNA相对表达量比较差异均无统计学意义(P均>0.05);与空白组比较,模型组小鼠p-AMPK蛋白相对表达量明显降低(P<0.05),SREBP-1c蛋白和mRNA相对表达量均明显升高(P均<0.05);与模型组比较,二甲双胍组及益气健脾汤组p-AMPK蛋白相对表达量均明显升高(P均<0.05),SREBP-1c蛋白和mRNA相对表达量均明显降低(P均<0.05),并且益气健脾汤组SREBP-1c蛋白和mRNA相对表达量均明显低于二甲双胍组(P均<0.05)。结论益气健脾汤可以通过调控AMPK/SREBP-1c信号通路改善非酒精性脂肪性肝病小鼠的胰岛素抵抗,抑制脂质合成,进而改善糖脂代谢。

Yiqi Yangyin and Huatan Quyu granule can improve skeletal muscle energy metabolism in a type 2 diabetic rat model by promoting the AMPK/SIRT/PGC-1α signalling pathway

Objective:To investigate how Yiqi Yangyin and Huatan Quyu granule (YYHO) improves skeletal muscle insulin resistance in a type 2 diabetic rat model and to discover whether the molecular mechanism is related to the promotion of the AMPK/SIRT/PGC-1α signalling pathway.Methods:Rats were randomly divided into 4 groups:the normal group,the model group,the YYHQ granule group,and the pioglitazone group.The type 2 diabetic rat model was established by feeding a high-fat diet for 5 weeks along with a single intraperitoneal injection of 30 mg/kg streptozotocin (STZ).After modelling successfully,the appropriate drug was intragastrically administered to diabetic rats for 2 weeks,once per day.The YYHQ granule group was given a dose of 4.8 g/kg body weight per day,the pioglitazone group was given a dose of 1.35 mg/kg body weight per day.The doses for both groups were equivalent to the clinical equivalent dose based on a previous study.Other groups were gavaged with the same amount of saline water.Body weight,food intake,water intake,urine volume and grip strength were recorded weekly.The fasting blood glucose(FBG) was determined weekly using blood glucose test strips.The related glucose and lipid metabolism indexes,e.g.,fasting insulin (Fins),glycated haemoglobin (GHb),HOMA-IR,ISI,triglycerides (TG),total cholesterol (TC),high-density lipoprotein cholesterol (HDL-C),low-density lipoprotein cholesterol (LDL-C) and free fatty acid (FFA),were determined using biochemical method.The mRNA expression levels of adenosine monophosphate-activated protein kinase (AMPK),peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α),carnitine palmitoyl transterase-1 (CPT-1),Sirtuin 1 (SIRT1),and Sirtuin 3 (SIRT3) were assessed using quantitative real-time PCR (qRT-PCR).The protein expression levels of creatine kinase (CK),Ca2+ ATPase,α-Actin,AMPK,PGC-1α and CPT-1 were determined using enzyme-linked immunosorbent assay method (ELISA).Results:Body weight decreased significantly (P <.01),food intake,water intake and urine volume increased significantly (P <.01),and grip strength decreased significantly (P <.01) in the model group compared with the normal group.The levels of FBG,Fins,GHb and HOMA-IR increased significantly (P <.01),and the ISI decreased significantly (P <.01) in the model group.The levels of TG,TC,LDL-C and FFA increased significantly (P <.05 or P <.01),and the level of HDL-C decreased significantly (P <.05) in the model group.These changes were reversed after treatment with YYHQ granule or pioglitazone.Compared with the model group,the YYHQ granule and pioglitazone groups significantly improve body weight,water intake and urine volume (P <.05 or P <.01),however,both treatments had no significant effect on food intake (P >.05).The levels of FBG,Fins,GHb,HOMA-IR and ISI were improved significantly (P <.01) and the levels of TG,TC and LDL-C were improved significantly (P <.05 or P <.01),however,both treatments had no significant effect on the levels of HDL-C and FFA (P >.05).Further results indicated that YYHQ granule significantly decreased the mRNA expression of AMPK,PGC-1α,CPT-1,SIRT1 and SIRT3 in skeletal muscle (P <.01) and the pioglitazone group showed similar effects;moreover,the protein expression levels of CK,Ca2+ATPase,α-Actin,AMPK,PGC-1α and CPT-1 in skeletal muscle significantly decreased (P <.01),however,pioglitazone had no significant effect on CK and α-Actin (P >.05).Conclusion:The possible molecular mechanism of YYHQ granule improving skeletal muscle insulin resistance in a type 2 diabetic rat model may be related to the stimulation of energy metabolism in skeletal muscle via the AMPK/SIRT/PGC-1α signalling pathway.

萆薢总皂苷调控AMPK/SREBP-1c/ACC信号通路改善小鼠非酒精性脂肪性肝炎

目的:研究萆薢总皂苷(TSD)改善小鼠非酒精性脂肪性肝炎(NASH)的作用及机制。方法:将48只C57BL/6J小鼠随机分为正常组和造模组,采用高脂高胆固醇饲料+20%果糖水喂养16周,将造模组小鼠随机分为模型组、阿托伐他汀组(4 mg·kg^(-1)·d^(-1))、TSD高、中、低剂量组(200、60、20 mg·kg^(-1)·d^(-1)),灌胃给药,连续8周。测定小鼠活动度、肝脏系数、肝脏总胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(FFA)及血清TC、TG、天冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、γ-谷氨酰转移酶(GGT)、白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)水平;苏木素-伊红(HE)染色、Masson染色、油红O染色和透射电子显微镜观察肝组织和肝细胞病理变化、脂质蓄积情况和肝脏超微结构形态学变化;蛋白免疫印迹法(Western blot)检测肝脏组织AMP活化蛋白激酶(AMPK)、固醇调节元件结合蛋白-1c(SREBP-1c)、乙酰辅酶A羧化酶(ACC)及其磷酸化形式的蛋白表达。结果:与正常组比较,模型组小鼠活动度明显降低(P<0.05,P<0.01),小鼠肝脏TC、TG、FFA和血清TC、TG、ALT、AST、GGT、IL-1β、TNF-α水平、肝脏系数、肝脏病理评分均明显升高,肝脏组织p-AMPK/AMPK、p-ACC蛋白表达明显降低,SREBP-1c、ACC蛋白表达明显升高(P<0.05,P<0.01)。与模型组比较,阿托伐他汀组小鼠活动度明显增加(P<0.05),TSD各剂量组小鼠活动度无明显改变;TSD及阿托伐他汀组小鼠肝脏TC、TG、FFA和血清TC、TG、ALT、AST、GGT、IL-1β、TNF-α水平、肝脏系数、肝脏病理评分均明显降低,肝脏组织p-AMPK/AMPK、p-ACC蛋白表达明显升高,SREBP-1c、ACC蛋白表达明显降低(P<0.05,P<0.01)。结论:TSD可能通过调控AMPK/SREBP-1c/ACC信号通路减少脂质合成,从而改善小鼠NASH。

丹酚酸B调节SIRT1信号途径抑制H_(2)O_(2)诱导的NLRP3炎症小体激活

目的基于沉默信息调节因子1(SIRT1)/NOD样受体蛋白3(NLRP3)炎症小体途径探讨丹酚酸B(Sal B)抗氧化应激致细胞损伤的作用机制,以期阐明丹酚酸B抗心肌缺血的作用机制。方法采用体外构建H_(2)O_(2)诱导的氧化应激细胞模型,将H9c2细胞分为6组,分别为正常组、模型组(600μmol·L^(-1)H_(2)O_(2)刺激)、H_(2)O_(2)+丹酚酸B(5、10、20μmol·L^(-1))组和H_(2)O_(2)+丹酚酸B(20μmol·L^(-1))+EX527(10μmol·L^(-1))组。采用MTT法测定细胞活性;Hoechst染色法测定细胞凋亡;比色法及ELISA法分别测定乳酸脱氢酶(LDH)、白细胞介素(IL)-1β水平;采用DCFH-DA荧光探针检测细胞内活性氧(ROS)水平;采用JC-1荧光探针测定线粒体膜电位;Western Blot法测定H9c2细胞中NLRP3、半胱氨酸天冬氨酸蛋白酶1(Caspase-1)、凋亡相关斑点样蛋白(ASC),以及SIRT1信号通路相关的SIRT1、磷酸化AMP蛋白活化激酶α(p-AMPKα)、AMP蛋白活化激酶α(AMPKα)、过氧化物酶体增殖物激活受体γ共激活因子1α(PGC-1α)蛋白表达。结果与正常组比较,模型组细胞活力及线粒体膜电位明显降低(P<0.01),细胞凋亡程度及细胞内ROS、LDH和炎症因子IL-1β水平明显升高(P<0.01);与NLRP3炎症小体相关的NLRP3、Caspase-1和ASC蛋白表达显著上调(P<0.01),SIRT1、p-AMPKα/AMPKα和PGC-1α蛋白表达明显下调(P<0.01)。与模型组比较,丹酚酸B组的细胞活力以及线粒体膜电位显著升高(P<0.05,P<0.01),细胞凋亡程度及细胞内ROS、LDH及炎症因子IL-1β释放水平明显降低(P<0.01)。丹酚酸B能够明显上调SIRT1信号通路中SIRT1、p-AMPKα/AMPKα、PGC-1α蛋白表达(P<0.05,P<0.01),下调NLRP3炎症小体相关的NLRP3、Caspase-1和ASC蛋白表达(P<0.05,P<0.01),且呈一定量效关系。在应用SIRT1特异性抑制剂EX527干预后,丹酚酸B抑制H_(2)O_(2)诱导的NLRP3炎症小体激活作用被明显逆转。结论丹酚酸B可能通过激活SIRT1/AMPK/PGC-1α信号通路,抑制氧化应激诱导的NLRP3炎症小体的激活,继而发挥抗心肌缺血作用。

黄芩苷对高脂诱导HepG2细胞脂肪沉积及SIRT1相关因子表达的影响

目的研究黄芩苷(Baicalin,BA)对游离脂肪酸(FFA)诱导HepG2细胞脂肪沉积的影响及机制研究。方法选用0.75 mmol/L的FFA体外诱导HepG2细胞24 h,建立体外脂肪沉积模型。将细胞分为正常组、模型组、黄芩苷低、中、高剂量组。利用油红O染色及GPO-PAP酶法检测各组细胞内甘油三酯(TG)含量的变化,ELISA法检测各组细胞上清液炎症因子TNF-α、IL-6分泌量。Western Blot检测各组细胞内沉默信息调节因子1(SIRT1)、碳水化合物应答元件结合蛋白(ChREBP)、胆固醇调节元件结合蛋白-1c(SREBP-1c)以及脂肪酸合成酶(FAS)的蛋白含量。结果FFA诱导的HepG2细胞内脂质积聚明显,细胞内TG含量显著上升;药物干预后,3个药物组细胞内脂滴较模型组均有减少,且呈药物浓度依赖性;细胞内TG含量呈下降趋势,其中中剂量和高剂量药物组与模型组相比,差异具有统计学意义(P<0.05);Western Blot检测结果显示,与空白组相比,模型组SIRT1蛋白表达显著降低,SREBP-1c以及FAS的蛋白表达显著上升,与模型组相比,中、高剂量黄芩苷组细胞SIRT1蛋白表达显著上升,SREBP-1c、ChREBP以及FAS蛋白表达显著下降(P<0.05)。结论黄芩苷可以改善FFA诱导的HepG2细胞的脂肪沉积,减低细胞内TG的含量,其机制可能与调节SIRT1/SREBP-1c通路相关。

miR-132诱导动脉粥样硬化中血管内皮细胞的促炎症过程

目的:探讨miR-132能否调控动脉粥样硬化的促炎性过程。方法:用miR-132模拟物和抑制剂转染人脐静脉内皮细胞,然后根据实验要求用或不用肿瘤坏死因子α(TNFα)处理,分从mRNA和蛋白水平检测SIRT1及其下游基因的表达量。结果:与对照组相比,转染miR-132的内皮细胞中,3′UTR荧光素酶活性(0.338±0.036)显著下降(P=0.000)。在人脐静脉内皮细胞中,miR-132能在mRNA水平及蛋白水平抑制SIRT1的表达(P<0.01)。同样,SREB、脂肪酸合酶及HMGCR的表达均出现下降。结论:miR-132直接作用于SIRT1的mRNA。在人脐静脉内皮细胞中,miR-132通过抑制SIRT1、SREBP-1c及其下游调控基因包括FASN和HMGCR的表达,控制脂肪生成和胆固醇生成。miR-132抑制SIRT1的表达,参与内皮细胞中脂质代谢依赖性的促炎性过程。miR-132可能是种新型的靶向治疗AS的方法。

AMPK参与调节大鼠脂肪肝相关性肝癌前病变的形成

目的探讨单磷酸腺苷活化蛋白激酶(adenosine monophosphate-activated protein kinase,AMPK)在低剂量二乙基亚硝胺(diethylnitrosamine,DEN)合并高脂饮食诱导的大鼠肝癌前病变发生中的作用及其机制。方法体内实验采用腹腔注射DEN(30 mg/kg)合并高脂饮食饲喂大鼠16周诱导肝癌前病变模型,通过HE染色、Western blotting、Real-time PCR、免疫组织化学等方法观察谷胱甘肽S转移酶(glutathione S-transferase-π,GST-π)、固醇调节元件结合蛋白1c(sterol regulatory element binding protein-1c,SREBP-1c)、脂肪酸合成酶(fatty acid synthase,FAS)、乙酰辅酶A羧化酶(acetyl-Co A carboxylase,ACC)、硬脂酰辅酶A去饱和酶1(stearoyl-Co A desaturase 1,SCD1)及AMPK、p-AMPK的表达变化;体外实验观察AMPK对棕榈酸(palmitic acid,PA)诱导的大鼠H4IIE细胞脂质代谢的影响。结果与单纯DEN处理组比较,DEN+高脂组大鼠肝细胞脂肪变性、气球样变、伴有炎性细胞浸润及小灶性坏死;GST-π表达水平增高;三酰甘油(triglyceride,TG)及SREBP-1c、FAS、ACC、SCD1表达水平上升;p-AMPK水平下降。AMPK通过抑制SREBP-1c的表达水平降低棕榈酸诱导的H4IIE细胞内脂质合成。结论 AMPK可能通过抑制SREBP-1c的表达水平参与大鼠肝癌前病变的形成。

Regulation effects of rosemary(Rosmarinus officinalis Linn) on hepatic lipid metabolism in OA induced NAFLD rats

OBJECTIVE To highlight the pharmacological effects of rosemary and its active compounds and eluci⁃date its related mechanisms in nonalcoholic fatty liver disease(NAFLD)management both in vitro and in vivo.METHODS In orotic acid induced NAFLD rats model,rats were administrated with 100,200 and 400 mg·kg^-1 rosemary ethanol extract(RO),10,25 and 50 mg·kg^-1 rosemary acid(RA),and 5,10 and 25 mg·kg^-1 carnosic acid(CA)for three weeks respec⁃tively.Sodium oleate induced HepG2 cell model was used to study the regulation effect of rosemary ethanol extract and its main metabolites on fat accumulation.lipid metabolism related gene expression was analyzed by Western blotting and real-time PCR to clarify the specific molecular mechanism of RO,RA and CA in lipid accumulation.RESULTS RO,RA and CA significantly reduced the contents of liver triglyceride(TG),total cholesterol(TC),free fatty acids(FFA)and improved cell hypertrophy,vacuolation,and cell necrosis in liver of orotic acid induced NAFLD model rats.The mecha⁃nism and related pathways of RO and its main metabolites against lipid disorder was related to the up-regulation of the phosphorylation of adenosine 5′-monophosphate(AMP)-activated protein kinase(AMPK)and inhibition of the sterol regu⁃latory element binding protein-1c(SREBP-1c)cracking into the nuclear,following down-regulation of fatty acid synthesis.CONCLUSION The rosemary has effectively function to regulate lipid metabolism through AMPK/SREBP1c signaling pathway.

Novel nervous and multi-system regenerative therapeutic strategies for diabetes mellitus with mTOR

Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin（m TOR） is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1（m TORC1） and m TOR Complex 2（m TORC2） and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase（PI 3-K）,protein kinase B（Akt）,AMP activated protein kinase（AMPK）,silent mating type information regulation 2 homolog 1（Saccharomyces cerevisiae）（SIRT1）,Wnt1 inducible signaling pathway protein 1（WISP1）,and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.

A soy glycinin derived octapeptide protects against MCD diet induced non-alcoholic fatty liver disease in mice

Soy glycinin derived octapeptide(SGP8)is a peptide obtained from degradation of the soy glycinin,whose amino acid sequence is IAVPGEVA.To determine the effect of SGP8 on non-alcoholic fatty liver disease(NAFLD),steatosis Hep G2 cells were induced by 1 mmol/L free fatty acid(FFA)and C57 BL/6 J mice were fed with methionine-choline defi cient(MCD)diet for 3 weeks to establish NAFLD model.The results of oil red O staining and total cholesterol(TC)/triglyceride(TG)contents showed that SGP8 could signifi cantly reduce the lipid content of steatosis Hep G2 cells.In vivo,SGP8 lowered plasma alanine aminotransferase(ALT)and low density lipoprotein(LDL)content,normalized hepatic superoxide dismutase(SOD)and malondialdehyde(MDA)production,and reduced the severity of liver infl ammation.The results of Western blotting showed that SGP8 increased expression of Sirtuin-1(SIRT1)and phosphorylation level of AMP activated protein kinase(AMPK)in hepatocytes.Through activation of SIRT1/AMPK pathway,SGP8 downregulated the expression of sterol regulatory element binding protein 1 c(SREBP-1 c)and its target genes ACC and FAS expression levels,and increased the phosphorylation level of acetyl Co A carboxylase(ACC).Furthermore,SGP8 also upregulated the expression of transcription factor peroxisome proliferator activated receptorα(PPARα),which was regulated by SIRT1/AMPK pathway,and its target gene CPT1 level.In conclusion,SGP8 might improve NAFLD by activating the SIRT1/AMPK pathway.Our data suggest that SGP8 may act as a novel and potent therapeutic agent against NAFLD.

Fanlian Huazhuo Formula alleviates high-fat diet-induced nonalcoholic fatty liver disease by modulating autophagy and lipid synthesis signaling pathway

BACKGROUND Fanlian Huazhuo Formula(FLHZF)has the functions of invigorating spleen and resolving phlegm,clearing heat and purging turbidity.It has been identified to have therapeutic effects on type 2 diabetes mellitus(T2DM)in clinical application.Non-alcoholic fatty liver disease(NAFLD)is frequently diagnosed in patients with T2DM.However,the therapeutic potential of FLHZF on NAFLD and the underlying mechanisms need further investigation.AIM To elucidate the effects of FLHZF on NAFLD and explore the underlying hepatoprotective mechanisms in vivo and in vitro.METHODS HepG2 cells were treated with free fatty acid for 24 hours to induce lipid accumulation cell model.Subsequently,experiments were conducted with the different concentrations of freeze-dried powder of FLHZF for 24 hours.C57BL/6 mice were fed a high-fat diet for 8-week to establish a mouse model of NAFLD,and then treated with the different concentrations of FLHZF for 10 weeks.RESULTS FLHZF had therapeutic potential against lipid accumulation and abnormal changes in biochemical indicators in vivo and in vitro.Further experiments verified that FLHZF alleviated abnormal lipid metabolism might by reducing oxidative stress,regulating the AMPKα/SREBP-1C signaling pathway,activating autophagy,and inhibiting hepatocyte apoptosis.CONCLUSION FLHZF alleviates abnormal lipid metabolism in NAFLD models by regulating reactive oxygen species,autophagy,apoptosis,and lipid synthesis signaling pathways,indicating its potential for clinical application in NAFLD.

表没食子儿茶素没食子酸酯对小鼠非酒精性脂肪肝的干预作用

本文研究了表没食子儿茶素没食子酸酯(EGCG)对小鼠非酒精性脂肪性肝病(NAFLD)的干预作用。应用高脂饲料喂养Apo E-/-小鼠建立NAFLD小鼠模型,研究EGCG对NAFLD小鼠血液和肝组织中糖脂代谢、脂肪酸氧化、氧化应激水平、肝组织结构以及AMPK/SIRT1/SREBP-1c/PPARγ信号通路相关基因表达的影响。结果表明EGCG治疗后肝组织病理学变化明显改善,小鼠体质量、肝质量、肝质量指数较模型组显著降低至110.98%、115.01%,115.64%、136.48%和104.20%、118.70%(p<0.01);血液和肝组织中糖脂代谢、脂肪酸氧化、氧化应激水平改善幅度在11.85%~86.06%之间,与模型组比较具有显著性差异(p<0.05或p<0.01);升高肝组织中AMPKα、SIRT1 mRNA及p-AMPKα、SIRT1蛋白表达幅度在13.21%~75.82%之间,降低肝组织FASN、ACC-1、SREBP-1c、SCD-1、PPARγm RNA和FASN、p-ACC-1、p-SREBP-1c、SCD-1、PPARγ蛋白表达幅度在19.59%~92.07%之间,改善p-AMPKα/AMPKα、p-ACC-1/ACC-1和p-SREBP-1c/SREBP-1c比率在39.20%~93.07%之间,与模型组比较具有显著性差异(p<0.05或p<0.01)。本研究表明EGCG可通过调控AMPK/SIRT1/SREBP-1c/PPARγ信号通路相关基因的表达来改善NAFLD小鼠糖脂代谢、脂肪酸氧化和氧化应激状态。

金黄地鼠高脂血症模型甘油三酯代谢紊乱的生物标志物的研究

目的建立金黄地鼠高脂血症模型,并研究甘油三酯代谢紊乱的分子机制。方法金黄地鼠随机分为正常组和模型组,正常组饲常规饲料,模型组饲高脂饲料,连续诱导4周。于第2、4周检测血清TG、TC、LDL-C、FFA水平和LPL活性,应用荧光实时定量PCR技术探讨甘油三酯代谢紊乱的分子机制。同时观察阳性药非诺贝特对金黄地鼠高脂血症模型血脂的影响。结果金黄地鼠造模2周时,血清TG、TC、LDL-C、FFA与对照组比较分别升高2.57、1.93、2.49和1.25倍;造模4周时分别升高3.93、1.90、2.27和2.29倍。阳性药对TG和FFA升高有明显的抑制作用。机制研究表明,金黄地鼠造模后,肝脏AMPK、PPARα、CPT-1 mRNA表达降低,SREBP-1c、ACC、SCD-1、AGPAT2、DGAT2 mRNA表达上调。ApoB表达有上调趋势,MTTP和LPL表达有下调趋势,血浆LPL活性明显降低。这些酶、蛋白、受体的表达变化是金黄地鼠甘油三酯代谢紊乱的主要原因。结论金黄地鼠经高脂饲料诱导4周后形成了具有高甘油三酯血症特征的高脂血症模型,AMPK、SREBP-1c、ACC、SCD1、DGAT2、AGPAT2、PPARα、CPT-1、LPL既是金黄地鼠甘油三酯代谢紊乱的生物标志物,也是降甘油三酯药物的作用靶标。