Qili Qiangxin,a compound herbal medicine formula,alleviates hypoxia-reoxygenation-induced apoptotic and autophagic cell death via suppression of ROS/AMPK/mTOR pathway in vitro

ObjectiveQili Qiangxin (QLQX), a compound herbal medicine formula, is used effectively to treat congestive heart failure in China. However, the molecular mechanisms of the cardioprotective effect are still unclear. This study explores the cardioprotective effect and mechanism of QLQX using the hypoxia-reoxygenation (H/R)-induced myocardial injury model.MethodsThe main chemical constituents of QLQX were analyzed using high-performance liquid chromatography-evaporative light-scattering detection. The model of H/R-induced myocardial injury in H9c2 cells was developed to simulate myocardial ischemia–reperfusion injury. Apoptosis, autophagy, and generation of reactive oxygen species (ROS) were measured to assess the protective effect of QLQX. Proteins related to autophagy, apoptosis and signalling pathways were detected using Western blotting.ResultsApoptosis, autophagy and the excessive production of ROS induced by H/R were significantly reduced after treating the H9c2 cells with QLQX. QLQX treatment at concentrations of 50 and 250 μg/mL caused significant reduction in the levels of LC3II and p62 degradation (P < 0.05), and also suppressed the AMPK/mTOR signalling pathway. Furthermore, the AMPK inhibitor Compound C (at 0.5 μmol/L), and QLQX (250 μg/mL) significantly inhibited H/R-induced autophagy and apoptosis (P < 0.01), while AICAR (an AMPK activator, at 0.5 mmol/L) increased cardiomyocyte apoptosis and autophagy and abolished the anti-apoptotic effect of QLQX. Similar phenomena were also observed on the expressions of apoptotic and autophagic proteins, demonstrating that QLQX reduced the apoptosis and autophagy in the H/R-induced injury model via inhibiting the AMPK/mTOR pathway. Moreover, ROS scavenger, N-Acetyl-L-cysteine (NAC, at 2.5 mmol/L), significantly reduced H/R-triggered cell apoptosis and autophagy (P < 0.01). Meanwhile, NAC treatment down-regulated the ratio of phosphorylation of AMPK/AMPK (P < 0.01), which showed a similar effect to QLQX.ConclusionQLQX plays a cardioprotective role by alleviating apoptotic and autophagic cell death through inhibition of the ROS/AMPK/mTOR signalling pathway.     

迷迭香酸通过AMPK/mTOR通路减轻新生大鼠缺血缺氧性脑损伤研究

目的 探讨迷迭香酸对新生大鼠缺血缺氧脑损伤（hypoxic-ischemic encephalopathy,HIE）的影响,及其对单磷酸腺苷活化蛋白激酶（adenosine monophosphate activated protein kinase,AMPK）/雷帕霉素靶蛋白（mammalian target of rapamycin,mTOR）通路的调控作用,初步探讨其脑保护机制。方法 取7 d龄SD新生大鼠,随机分为对照组、模型组、迷迭香酸（300 mg/kg）组、AMPK/mTOR激动剂MT6378（10 mg/kg）组、AMPK抑制剂GSK-690693（30 mg/kg）组和迷迭香酸（300 mg/kg）+MT6378（10 mg/kg）组,每组20只。建立HIE模型,给予相应药物进行干预,采用TTC染色法检测大鼠脑梗死情况;透射电镜（TEM）观察大鼠海马神经元结构损伤及自噬状况;免疫荧光法检测大鼠海马神经元自噬标记物微管相关蛋白1轻链3B（microtubule-associated protein 1 light chain 3B,LC3B）阳性表达;TUNEL法检测大鼠海马神经元凋亡率;免疫组化法检测大鼠海马神经元磷酸化AMPK（p-AMPK）阳性表达;Western blotting检测大鼠海马组织活化的半胱氨酸蛋白酶3（cleaved Caspase-3）、mTOR及其磷酸化蛋白（p-mTOR）、Unc-51样自噬激活激酶1（uncoordinated-51 like autophagy activating kinase 1,Ulk1）及其磷酸化蛋白（p-Ulk1）、LC3B表达。结果 与对照组相比,模型组大鼠脑梗死严重,海马神经元结构损伤及自噬空泡形成较多,细胞自噬及凋亡水平升高,AMPK/mTOR通路活化（P<0.05）。与模型组相比,迷迭香酸组及GSK-690693组大鼠脑梗死、海马神经元结构损伤、凋亡及自噬减弱,AMPK/mTOR通路被抑制（P<0.05）;MT6378组海马组织AMPK/mTOR通路进一步激活,大鼠脑梗死、海马神经元结构损伤、凋亡及自噬进一步加重（P<0.05）;MT6378可逆转迷迭香酸的上述作用（P<0.05）。结论 迷迭香酸可能通过抑制AMPK/mTOR通路激活,降低海马神经元自噬及凋亡进程,发挥抗HIE脑损伤作用。     

Tanshinone IIA Induces Autophagic Cell Death via Activation of AMPK and ERK and Inhibition of mTOR and p70 S6K in KBM‐5 Leukemia Cells

Although tanshinone IIA (Tan IIA) from Salviae miltiorrhizae was known to induce apoptosis in various cancers, its underlying mechanism of autophagic cell death was not reported yet. Thus, in the present study, the molecular mechanism of autophagic cell death by Tan IIA was investigated in KBM‐5 leukemia cells. Tan IIA significantly increased the expression of microtubule‐associated protein light chain 3 (LC3) II as a hallmark of autophagy in western blotting and immunofluorescence staining. Tan IIA augmented the phosphorylation of adenosine monophosphate‐activated protein kinase (AMPK) and attenuated the phosphorylation of mammalian target of rapamycin (mTOR) and p70 S6K in a dose‐dependent manner. Conversely, autophagy inhibitor 3‐methyladenine partly reversed the cytotoxicity and the phosphorylation of AMPK, mTOR and p70 S6K induced by Tan IIA in KBM‐5 leukemia cells. In addition, Tan IIA dramatically activated the extracellular signal regulated kinase (ERK) signaling pathway including Raf, ERK and p90 RSK in a dose‐dependent and time‐dependent manner. Consistently, ERK inhibitor PD184352 suppressed LC3‐II activation induced by Tan IIA, whereas PD184352 and PD98059 did not affect poly (ADP‐ribose) polymerase cleavage and sub‐G1 accumulation induced by Tan IIA in KBM‐5 leukemia cells. Furthermore, Tan IIA could induce autophagy via LC3‐II activation in various cancer cells such as prostate (PC‐3), multiple myeloma (U266), lung (NCI‐H460), and breast (MDA‐MB‐231) cells. Overall, these findings suggest that Tan IIA induces autophagic cell death via activation of AMPK and ERK and inhibition of mTOR and p70 S6K in KBM‐5 cells as a potent natural compound for leukemia treatment. Copyright © 2013 John Wiley & Sons, Ltd.     

Thymoquinone attenuates hepatic lipid accumulation by inducing autophagy via AMPK/mTOR/ULK1-dependent pathway in nonalcoholic fatty liver disease

Thymoquinone (TQ) has been proved to exert wide-ranging pharmacological activities, with anti-inflammatory, antioxidant, anticonvulsant, antimicrobial, anti-tumor, and antidiabetic properties. In this study, we investigated the beneficial effects of TQ on a high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) in C57BL/6 N mice in vivo and free fatty acid (FFA)-induced human hepatocellular carcinoma HepG2 cells in vitro. Further, the underlying mechanisms of TQ to promote hepatic autophagy were also discovered. Data showed that TQ caused (p < 0.01) body weight reduction, improved glucose homeostasis, alleviated hepatosteatosis, and decreased hepatic lipid accumulation related to the induction of autophagy in HFD-fed mice. In vitro, TQ obviously increased (p < 0.01) autophagic flux in FFA-induced HepG2 cells and consequently reduced the lipid accumulation in combination with activation of AMPK/mTOR/ULK1 signaling pathways. Moreover, pharmacological inhibition of the AMPK pathway by addition with AMPK inhibitor Compound C (CC) or silence of ULK1 by transfection with siRNA(ULK1) into HepG2 cells reversed these beneficial effects of TQ on triggering hepatic autophagy and reducing lipid accumulation (p < 0.01). Taken together, these results suggested that TQ alleviated hepatic lipid accumulation by triggering autophagy through the AMPK/mTOR/ULK1-dependent signaling pathway. Our study supports a potential role for TQ in ameliorating NAFLD.     

活血消瘿方含药血清调控AMPK/mTOR通路对脂多糖诱导的甲状腺滤泡上皮细胞自噬和凋亡的影响

目的 探讨活血消瘿方含药血清对脂多糖(LPS)诱导的甲状腺滤泡上皮细胞(TFECs)自噬和凋亡的影响以及作用机制。方法 光学显微镜观察分离培养的SD大鼠TFECs细胞的形态;免疫荧光染色鉴定TFECs中特异抗原甲状腺球蛋白(Tg)。取对数生长期的TFECs,分为对照组、LPS组、含药血清组、含药血清+compound C(AMPK抑制剂)组、含药血清+MHY1485(mTOR激活剂)组,MTT法检测各组细胞活力;绿色荧光蛋白(GFP)标记质粒转染检测各组细胞自噬小体变化;流式细胞术检测各组细胞凋亡;western blot检测各组细胞中微管相关蛋白1轻链3(LC3)I、LC3II、Beclin1、Bcl-2相关X蛋白(Bax)、B淋巴细胞瘤-2(Bcl-2)及AMP活化蛋白激酶(AMPK)/哺乳动物雷帕霉素靶蛋白(mTOR)通路相关蛋白表达。结果 光学显微镜观察显示,TFECs形态为梭形、形态均一,且可成簇生长。免疫荧光结果显示,TFECs细胞质中可见较强的Tg荧光染色。与对照组比较,LPS组TFECs细胞活力、自噬小体数量、LC3II/LC3I、Beclin1、Bcl-2、p-AMPK/AMPK蛋白相对表达量显著降低,炎性因子IL-6 、TNF-α水平、细胞凋亡率、Bax、p-mTOR/mTOR蛋白相对表达量显著升高(P< 0.05);与LPS组比较,含药血清组TFECs细胞活力、自噬小体数量、LC3II/LC3I、Beclin1、Bcl-2、p-AMPK/AMPK蛋白相对表达量显著升高,炎性因子IL-6 、 TNF-α水平、细胞凋亡率、Bax、p-mTOR/mTOR蛋白相对表达量显著降低(P< 0.05);与含药血清组比较,含药血清+compound C组、含药血清+MHY1485组TFECs中相应指标与上述趋势相反。结论 活血消瘿方含药血清对LPS诱导的TFECs自噬的促进作用及细胞凋亡的抑制作用可能与激活AMPK/mTOR通路有关。     

大黄素诱导自噬改善顺铂导致肾小管细胞损伤机制探索

目的：观察大黄素对顺铂所致的肾小管上皮细胞（NRK-52E）损伤的影响,探讨其可能分子调节机制。方法：观察大黄素对顺铂所致NRK-52E细胞形态学改变的影响;采用Western Blot方法检测顺铂单独处理和加入大黄素共同处理细胞后,凋亡相关蛋白Caspase-3和cleaved Caspase-3的表达情况;用大黄素干预细胞不同的时间点,观察微管相关蛋白1轻链3（LC3）II/I的表达和pmRFP-LC3质粒转染细胞后荧光颗粒的变化情况,同时观察雷帕霉素处理细胞不同时间点后LC3-II/I的表达情况及其对顺铂环境下细胞形态学改变的影响,并观察大黄素对自噬上游通路AMPK的活化和mTOR信号的影响。结果：顺铂可以诱导NRK-52E细胞出现形态学改变,大黄素能够改善顺铂导致的变化。另外,大黄素干预可以下调顺铂导致的cleaved Caspase-3蛋白表达的增多;大黄素处理细胞不同时间点LC3-II/LC3-I的比值明显上升,pmRFP-LC3转染观察到大黄素处理细胞后自噬颗粒明显增多。同时雷帕霉素处理细胞后LC3-II/LC3-I的比值明显上升,其与顺铂共同干预能明显改善顺铂诱导的细胞凋亡;大黄素干预时间的延长,p-mTOR蛋白表达明显下调,p-AMPK的表达明显上调。结论：大黄素可以改善顺铂诱导的NRK-52E细胞凋亡,其作用机制可能是通过调节AMPK/mTOR信号通路诱导自噬来发挥肾保护作用。     

当归多糖对糖尿病肾病KK-Ay小鼠肾脏AMPK信号通路及线粒体自噬的影响

目的 研究当归多糖对糖尿病肾病（diabetic nephropathy,DN）KK-Ay小鼠肾脏磷酸腺苷激活的蛋白激酶（AMPactivated protein kinase,AMPK）信号通路及线粒体自噬的影响。方法 SPF级雄性KK-Ay小鼠用高糖高脂饲料喂养,随机分为模型组、厄贝沙坦（25 mg/kg）组和当归多糖高、中、低剂量（400、200、100 mg/kg）组,每组10只;将10只雄性C57BL/6J小鼠作为对照组。给予药物干预4周,观察小鼠一般情况,每周称定体质量并检测血糖;末次给药后,心脏取血并处死小鼠,分离血清检测尿微量白蛋白（urine microalbuminuria,U-ALB）、肌酐（creatinine,SCr）、尿素氮（urea nitrogen,BUN）;采用苏木素-伊红（HE）染色观察肾组织病理变化;采用Western blotting检测肾组织线粒体自噬相关蛋白[微管相关蛋白1轻链3(microtubule-associated protein 1 light chain 3,LC3)、p62、Nix]和线粒体裂变蛋白[线粒体动力相关蛋白1(dy...     

养心康片通过Akt/AMPK-mTOR通路对心肌梗死后心力衰竭模型兔心肌细胞自噬的影响

目的观察养心康片通过Akt/AMPK-mTOR通路对心肌梗死后心力衰竭模型兔心肌细胞自噬的影响。方法对实验兔应用结扎冠脉的方法建立心肌梗死后心力衰竭兔模型,随机分为模型组、养心康组、AMPK抑制剂组、Akt抑制剂组和mTOR抑制剂组。并另取不造模的兔设立空白对照组。每组5只,共30只。造模后第3天开始分别给予相应的处理措施,共4周。观察养心康片对模型兔心肌beclin 1、LC3蛋白表达,心肌beclin 1和Atg5 mRNA的表达的影响,电镜检测各组心肌细胞超微结构。结果养心康组的beclin 1 mRNA的表达量、beclin 1蛋白表达量较模型组、mTOR抑制剂组降低(P<0.05或P<0.01),较空白对照组、AMPK抑制剂组升高(P<0.05或P<0.01);养心康组的LC3-Ⅱ/LC3-I比值较模型组、mTOR抑制剂组降低(P<0.05),较空白对照组、AMPK抑制剂组升高(P<0.05)。养心康组的Atg5 mRNA表达量较模型组降低(P<0.05),较空白对照组、AMPK抑制剂组升高(P<0.05或P<0.01)。电镜结果显示养心康组的自噬体、自噬体溶酶体数量较模型组、Akt抑制剂组和mTOR抑制剂组降低减少,较AMPK抑制剂组增多。结论养心康片可通过干预Akt/AMPK-mTOR通路调控心肌细胞自噬水平,改善心肌梗死后心衰模型的心肌细胞超微结构。     

知母皂苷元通过AMPK-mTOR-ULK1途径抑制肾小球系膜基质合成和激活自噬治疗糖尿病肾病的研究

目的探究知母皂苷元基于AMPK-mTOR-ULK1途径对糖尿病肾病大鼠的干预作用。方法将40只SD大鼠随机分为对照组、模型组、知母皂苷元低剂量组、知母皂苷元高剂量组和二甲双胍组,每组8只。除对照组外,其余组采用高脂饲料饲喂联合链脲佐菌素(STZ)诱导建立糖尿病模型。知母皂苷元低、高剂量组大鼠分别灌胃20 mg/(kg·d)和60 mg/(kg·d)知母皂苷元,二甲双胍组灌胃500 mg/(kg·d)二甲双胍,其余组灌胃等量生理盐水,连续8周。检测各组大鼠血糖、24 h尿蛋白、尿素氮、肌酐水平,HE染色和PAS染色观察大鼠肾脏病理组织学变化,检测肾组织中α-SMA表达情况和Ⅰ型胶原、Ⅳ型胶原、纤维连接蛋白含量,Western blot法检测肾组织中Beclin-1、LC3、AMPK、p-AMPK、mTOR、p-mTOR、ULK1和p-ULK1表达量。结果与对照组比较,模型组大鼠血糖、24 h尿蛋白、尿素氮、肌酐水平和肾重/体重均显著增高(P均<0.05);肾脏组织结构紊乱,肾小球基底膜增厚;肾小球体积、系膜基质面积、α-SMA阳性面积和Ⅰ型胶原、Ⅳ型胶原、纤维连接蛋白含量及p-mTOR/mTOR表达量均显著升高(P均<0.05),Beclin-1、LC3-Ⅱ/LC3-Ⅰ、p-AMPK/AMPK、p-ULK1/ULK1表达量均显著降低(P均<0.05)。与模型组比较,二甲双胍组大鼠血糖和知母皂苷元低剂量组、知母皂苷元高剂量组、二甲双胍组大鼠24 h尿蛋白、尿素氮、肌酐水平和肾重/体重均显著降低(P均<0.05);肾脏病理组织学变化得到明显改善;肾小球体积、系膜基质面积、α-SMA阳性面积和Ⅰ型胶原、Ⅳ型胶原、纤维连接蛋白含量及p-mTOR/mTOR表达量均显著降低(P均<0.05),Beclin-1、LC3-Ⅱ/LC3-Ⅰ、p-AMPK/AMPK、p-ULK1/ULK1表达量均显著增高(P均<0.05)。结论知母皂苷元可通过AMPK-mTOR-ULK1途径抑制肾小球系膜基质合成和激活自噬改善大鼠糖尿病肾病。     

丹参酮Ⅱa通过AMPK/mTOR通路调节自噬促进急性白血病细胞凋亡作用机制研究

目的观察丹参酮Ⅱa对HL-60的凋亡与自噬以及相关因子水平的影响,探讨丹参酮Ⅱa抗急性髓系白血病的分子机制。方法使用不同浓度的丹参酮Ⅱa处理HL-60细胞24、48 h后用CCK-8法检测增殖抑制率,吉姆萨染色观察细胞形态,Western blotting检测Caspase-3、Cleaved-Caspase-3、PARP-1、p-AMPK、pmTOR、LC3B水平变化,联用自噬抑制剂巴弗洛霉素A1以CCK-8测细胞存活率。结果以0、1、2、4、8、16、32、64、128μmol/L丹参酮Ⅱa处理HL-60细胞24、48 h后HL-60增殖被抑制,其作用随浓度增加和时间延长而加强,24、48 h的IC₅₀分别为32.87、18.4μmol/L;吉姆萨染色镜下观察见,随着药物浓度增加HL-60凋亡增加;Western blotting显示Caspase-3减少、Cleaved-Caspase-3增加,PARP-1切割增加,凋亡增强;p-AMPK增加、pmTOR减少、LC3B增加,显示AMPK/mTOR自噬通路激活,联用巴弗洛霉素A1后丹参酮Ⅱa增殖抑制作用减弱。结论丹参酮Ⅱa通过诱导HL-60凋亡和自噬发挥抗白血病作用,AMPK/mTOR可能是介导这一效应的重要信号通路。     

肝豆汤对Wilson病模型高铜诱导的SH-SY5Y细胞自噬效应的影响及其作用机制

目的:研究肝豆汤对高铜诱导的人神经母细胞瘤(SH-SY5Y)细胞自噬效应的影响及其作用机制,为中医药防治脑型Wilson病(Wilson disease,WD)提供新的治疗靶点和研究思路。方法:噻唑蓝(MTT)比色法筛选硫酸铜(CuSO_4)造模浓度(0,100,200,400,800,1 600μmol·L-1)及时间; MTT比色法筛选含药血清浓度(5%,10%,15%,20%)及时间;乳酸脱氢酶(LDH)释放实验检测细胞LDH漏出率;流式细胞法检测细胞内活性氧(ROS)的含量;荧光染料JC-1检测细胞线粒体膜电位;流式细胞仪对自噬进行定量分析。蛋白免疫印迹法(Western blot)检测肝激酶B1(LKB1),腺苷酸活化蛋白激酶(AMPK),自噬微管相关蛋白轻链3A/B(LC3A/B),哺乳动物雷帕霉素靶蛋白(mTOR),unc-51样激酶1(ULK1),磷酸化ULK(p-ULK),磷酸化AMPK(p-AMPK)蛋白的表达。结果:MTT结果显示,CuSO_4对细胞的损伤呈现一定的量效和时效关系(P 0. 01),随着CuSO_4作用浓度及时间的增加,细胞存活率呈现下降趋势; 10%含肝豆汤兔血清可显著抑制CuSO_4诱导的细胞死亡(P 0. 01)。LDH释放实验显示,与正常组比较,CuSO_4作用细胞后LDH漏出率显著增加(P 0. 01),与模型组比较,含肝豆汤兔血清明显降低CuSO_4损伤细胞的LDH漏出率(P 0. 05)。DCFH-DA荧光染色显示,与正常组比较,CuSO_4可显著增加细胞内ROS生成(P 0. 01),与模型组比较,含肝豆汤兔血清可显著抑制CuSO_4诱导的细胞内ROS产生(P 0. 01)。JC-1染色结果显示,与正常组比较,CuSO_4诱导细胞线粒体膜电位Δψm显著降低(P 0. 01),与模型组比较,含肝豆汤兔血清明显抑制CuSO_4诱导的线粒体膜电位降低Δψm(P 0. 05)。Western blot结果显示,与正常组比较,模型组细胞内LKB1,AMPK,LC3A/B,ULK1及p-AMPK蛋白的表达显著增加,mTOR及p-ULK蛋白的表达显著降低(P 0. 01)。与模型组比较,含肝豆汤兔血清组LKB1,AMPK,LC3A/B,ULK1及p-AMPK蛋白表达显著降低,mTOR及p-ULK蛋白表达显著增加(P 0. 01)。结论:高铜可通过诱导细胞内线粒体氧化应激,上调自噬相关蛋白LKB1,p-AMPK,AMPK,LC3A/B及ULK1的表达,下调自噬相关蛋白mTOR及p-ULK的表达,导致细胞发生自噬性死亡,而肝豆汤可通过调控LKB1/AMPK信号通路,下调自噬相关蛋白LKB1,p-AMPK,LC3A/B,ULK及AMPK的表达,上调自噬相关蛋白及基因mTOR及p-ULK的表达,抑制自噬的发生,阻断高铜诱导的神经元损伤,从而发挥神经保护作用。     

Resveratrol reverses TGF-β1-mediated invasion and metastasis of breast cancer cells via the SIRT3/AMPK/autophagy signal axis

Resveratrol (Resv) has antitumorigenic and antimetastatic activities; however, the molecular mechanisms underlying the inhibitory effects of Resv on the invasion and metastasis of breast cancer cells are still a subject of debate. In our study, we demonstrated that Resv inhibited tumor cell proliferation and tumor growth. It also suppressed invasion and pulmonary metastasis of breast cancer by reversing the transforming growth factor beta 1 (TGF-β1)-mediated EMT process. Meanwhile, the anticarcinogenic effects of Resv were abolished by the autophagy blocker 3-methyladenine (3-MA) or Beclin 1 small interfering RNA. Moreover, Resv upregulated autophagy-related genes and protein levels and induced the formation of autophagosomes in 4T1 breast cancer cells and xenograft mice, suggesting that autophagy was involved in the anticarcinogenic activities of Resv in both models. In addition, Resv-induced autophagy by increasing the expression of SIRT3 and phosphorylated AMPK. SIRT3 knockdown reduced AMPK phosphorylation and autophagy-related proteins levels, and suppressed the anticancer effects of Resv, demonstrating that the inhibitory effects of Resv on tumor progression were mediated via the SIRT3/AMPK/autophagy pathway. Taken together, our study provided novel insight into the anticancer effects of Resv and revealed that targeting the SIRT3/AMPK/autophagy pathway can serve as a new therapeutic target against breast cancer.     

大黄酸调控mTOR信号通路活性抑制肾小管上皮细胞自噬蛋白表达的分子机制

目的:探讨大黄酸抑制饥饿诱导的肾小管上皮(NRK-52E)细胞自噬蛋白的作用和分子机制。方法:用Hank’s平衡盐溶液(Hank’s balanced salt solution,HBSS)诱导NRK-52E细胞产生饥饿状态,在干预后的各时间点(0,0.5,1,2,6 h),首先,检测细胞自噬标志性蛋白——哺乳动物同族物微管相关蛋白1轻链3(microtubule-associated protein 1 light chain 3,LC3)I/II的表达水平;其次,检测细胞哺乳动物类雷帕霉素靶蛋白(mammalian target of rapamycin,m TOR)表达及其磷酸化水平(phosphorylated-m TOR Ser2448,p-m TOR S2448);然后,以大黄酸(5 mg·L-1)、HBSS(1 m L)以及m TOR抑制剂雷帕霉素(100 nmol·L-1)单独或联合干预,分别检测其LC3 I/II,m TOR,p-m TOR S2448蛋白表达水平的变化。结果:HBSS诱导NRK-52E细胞LC3II蛋白高表达、p-m TOR S2448蛋白低表达;大黄酸与HBSS联合干预可以逆转HBSS诱导的NRK-52E细胞LC3 II和p-m TOR S2448蛋白表达水平;雷帕霉素与大黄酸、HBSS联合干预可以恢复HBSS诱导的NRK-52E细胞LC3 II蛋白表达水平。结论:HBSS抑制m TOR信号通路活性而诱导肾小管上皮细胞发生自噬;大黄酸调控m TOR信号通路活性而抑制肾小管上皮细胞自噬蛋白的表达,这可能就是其干预细胞自噬的作用和分子机制。     

基于mTOR信号通路探讨中医药干预冠心病研究进展

雷帕霉素靶蛋白(mammalian target of rapamycin,m TOR)信号通路具有调控细胞生长、自噬、增殖和凋亡等生物学功能,在肿瘤、心脑血管疾病中发挥着重要作用。近年来mTOR信号通路的磷酸腺苷活化蛋白激酶(AMP-activated protein kinase,AMPK)/mTOR和蛋白激酶B(Akt)/mTOR通路日益受到重视。基于2条通路与冠心病关系及中医药的干预作用进行综述。     

背俞指针疗法对GERD大鼠食管下端组织的ICC内质网AMPK/mTOR自噬通路的影响

目的研究背俞指针疗法对胃食管反流病(gastroesophageal reflux disease,GERD)大鼠食管下端组织的ICC内质网中腺苷酸活化蛋白激酶(AMPK)和哺乳动物雷帕霉素靶蛋白(mTOR)mRNA及蛋白表达的影响,探讨背俞指针疗法的效应机制。方法将76只大鼠随机分为空白组、空白指针组、模型组、指针组。采用贲门钢圈固定法制作GERD动物模型,指针组予背俞指针疗法干预,疗程均为2周。干预结束后,切取大鼠食道下段组织制作标本。采用Western Blot检测食管下端组织ICC内质网中的AMPK和mTOR蛋白表达情况;采用逆转录聚合酶链反应(RT-PCR)检测食管下端组织ICC内质网的AMPK mRNA、mTOR mRNA水平。结果Western Blot检测结果表明:模型组AMPK蛋白表达低于空白组,指针组AMPK蛋白表达显著高于模型组,差异具有统计学意义(P<0.05);空白指针组AMPK蛋白表达与模型组比较,差异无统计学意义(P>0.05);mTOR蛋白表达情况组间比较差异均无统计学意义(P>0.05)。RT-PCR检测结果表明,mTOR mRNA及AMPK mRNA水平组间比较均无统计学差异(P>0.05)。结论GERD的发病机制可能与食管下段组织ICC AMPK蛋白水平下调有关,与AMPK/mTOR自噬信号通路可能不相关。背俞指针疗法治疗GERD的起效机制可能通过提高ICC细胞AMPK蛋白表达而实现。     

电针通过调节AMPK/mTOR/ULK1信号通路对衰老小鼠肝脏自噬与氧化应激的影响

目的:观察电针对衰老小鼠体力及肝脏AMP活化的蛋白激酶(AMPK)、哺乳动物雷帕霉素靶蛋白(mTOR)、unc-51样自噬激活激酶1(ULK1)、Atg5、Atg7、Atg13和Beclin1表达的影响,探索其通过激活AMPK/mTOR/ULK1通路延缓衰老的机制.方法:将30周龄雄性SAMP8小鼠随机分为模型组、雷帕...     

mTOR信号通路调控糖尿病肾病肾小球肥大的机制及中药的干预作用

肾小球肥大(glomerular hypertrophy)是糖尿病肾病(diabetic nephropathy,DN)早期阶段最主要的病理特征,其调控机制与哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号通路活性密切相关。mTOR包括mTORC1和mTORC2,其中,mTORC1上游信号通路是磷脂酰肌醇3激酶(phosphatidylinositol-3-kinase,PI3K)/丝氨酸-苏氨酸激酶(serine-threonine kinase,Akt)/5-单磷酸腺苷活性蛋白激酶(adenosine monophosphate activated protein kinase,AMPK),其代表性的下游信号分子是4E结合蛋白(4E-binding proteins,4EBP)和70 kD核糖体S6激酶(phosphoprotein 70 S6Kinase,p70S6K)。一些中药提取物可以在体外通过干预PI3K/Akt/mTOR信号通路关键上、下游信号分子的表达而改善细胞增殖。对于肾小球系膜细胞和足细胞,mTOR通过调节细胞周期、能量代谢以及相关的基质蛋白合成等多种途径对肾小球固有细胞发挥着重要的调控作用。对于DN动物模型,mTOR抑制剂——雷帕霉素可抑制肾小球固有细胞肥大、增殖以及相应的肾小球基底膜增厚和系膜基质沉积。一些中药提取物在体内外可以通过干预DN肾组织或肾脏固有细胞mTOR信号通路的活性而减轻相应的肾小球病变。     

6-Methoxydihydrosanguinarine induces apoptosis and autophagy in breast cancer MCF-7 cells by accumulating ROS to suppress the PI3K/AKT/mTOR signaling pathway

6-Methoxydihydrosanguinarine (6-MDS) is a natural benzophenanthridine alkaloid extracted from Hylomecon japonica (Thunb.) Prantl. It is the first time to explore the effect and mechanism of 6-MDS in breast cancer. Network pharmacology, molecular docking, and molecular dynamics simulation technology were adopted to identify the potential targets and pathways of 6-MDS in breast cancer. Besides, cell proliferation, apoptosis, and western blotting assays were conducted to investigate the effect of 6-MDS on MCF-7 cells. Network pharmacology, molecular docking, and molecular dynamics simulation results confirmed the effect of 6-MDS on resisting breast cancer via the PI3K/AKT/mTOR signaling pathway. In addition, the functional experiments results demonstrated that 6-MDS inhibited proliferation and induced apoptosis and autophagy. The autophagy inhibitor chloroquine and the silence of Atg5 augmented the effect of 6-MDS on promoting apoptosis. Furthermore, 6-MDS suppressed the PI3K/AKT/mTOR signaling pathway, and the PI3K inhibitor LY294002 enhanced these changes and promoted the 6-MDS pro-apoptotic and autophagy effects. 6-MDS triggered the generation of reactive oxygen species. The pretreatment with antioxidant N-acetyl-L-cysteine reversed the changes induced by 6-MDS, including increases in apoptosis and autophagy and inhibition of the PI3K/AKT/mTOR pathway. In conclusion, 6-MDS induces the apoptosis and autophagy of MCF-7 cells by ROS accumulation to suppress the PI3K/AKT/mTOR signaling pathway.     

基于AMPK/mTOR信号通路探讨左、右归丸对绝经后骨质疏松症大鼠骨吸收的影响

目的:观察左、右归丸对绝经后骨质疏松症(PMOP)大鼠骨组织AMPK/mTOR基因与蛋白表达影响,并基于此信号通路对PMOP大鼠骨吸收进行实验研究,探索其防治PMOP的作用机制。方法:将60只SD大鼠随机分为空白(KB)组、假手术(SHAM)组、模型(OVX)组、左归丸(ZGW)组、右归丸(YGW)组、补佳乐(BJL)组。经过12周治疗后,应用数字化全身骨密度仪进行腰椎骨密度(BMD)检测,以ELISA法检测大鼠血清中Ⅰ型前胶原羟基端前肽(PICP)含量,以荧光定量-PCR和Western blot检测骨组织中OPG、RANKL、AMPK、mTOR基因和蛋白的表达。结果:与KB组比较,OVX组大鼠BMD、OPG、mTOR基因和蛋白表达显著降低(P<0.01);血清中PICP含量、RANKL、AMPK基因和蛋白表达显著升高(P<0.01);与OVX组比较,各治疗组BMD、OPG、mTOR基因和蛋白表达显著升高(P<0.01,P<0.05);血清PICP含量、RANKL、AMPK基因和蛋白表达显著降低(P<0.01,P<0.05)。结论:左、右归丸基于AMPK/mTOR信号通路可影响骨组织中OPG、RANKL基因与蛋白的表达,这可能是其调控骨吸收的机制之一。     

黄芪多糖抑制缺氧/复氧损伤乳鼠心肌细胞凋亡与自噬机制研究

目的:探讨黄芪多糖(APS)对缺氧/复氧(H/R)所致乳鼠心肌细胞凋亡与自噬抑制作用的相关机制。方法:分离并体外培养乳鼠心肌细胞3 d后制备H/R损伤细胞模型,设正常对照组、H/R组、APS低、中、高剂量(20、40、80 μmol/ml)组,各组于造模前30 min给药处理。复氧2 h后,CCK-8法检测细胞增殖抑制率,Annexin V-FITC/PI染色法检测细胞凋亡水平,Western blot法检测p-Akt、Cleaved Caspase-3、Bcl-2、Bax、p-mTOR、Beclin1、LC3、P62蛋白表达。结果:与H/R组比较,APS中、高剂量细胞增殖抑制率和凋亡率显著降低(P<0.01),p-Akt、p-mTOR、Bcl-2表达量显著升高而Cleaved Caspase-3、Bax、Beclin1、LC3-Ⅰ、LC3-Ⅱ、P62表达量显著降低(P<0.05),Bcl-2/Bax比值显著升高、LC3-Ⅱ/LC3-Ⅰ比值显著降低(P<0.01)。结论:APS可能通过激活Akt/mTOR通路调控凋亡和自噬相关蛋白表达,对H/R所致乳鼠心肌细胞凋亡与自噬起到抑制作用。