Resveratrol attenuates intestinal injury in irradiated rats via PI3K/Akt/mTOR signaling pathway

Radiation‐induced enteritis is one of the greatest challenges in radiotherapy. The current study was designed to evaluate the ameliorative effect of resveratrol, which exhibits anti‐inflammatory property, against radiation‐induced intestinal injury in rats and to explore the underlying mechanism. Rats were exposed to a single dose of 5 Gy. Resveratrol (20 mg/kg/day) was orally administered to irradiated rats over 3 weeks. Results showed that resveratrol ameliorated the intestinal oxidative stress parameters; malondialdehyde (MDA) content, glutathione (GSH) level, and catalase (CAT) activity compared to irradiated group. Furthermore, resveratrol reduced the contents of inflammatory cytokines; tumor necrosis factor α (TNF‐α), nuclear factor‐kappa (NF‐κB), and interleukin 1β (IL‐1β) in intestine. Western blotting analysis revealed that resveratrol down‐regulated the proteins expression of phosphoinositide 3‐kinases (PI3K), protein kinase B (Akt) as well as the mammalian target of rapamycin (mTOR) in intestinal tissues of irradiated rats and thus reduced the inflammatory mediator production. These results were confirmed by histopathological investigation. In conclusion, resveratrol attenuated intestinal inflammation following irradiation via modulating PI3K/Akt/mTOR pathway and thereby could be a promising adjuvant in radiotherapy.     

BAFF/BAFF-R通过PI3K/Akt/mTOR信号转导通路调节B淋巴细胞功能在类风湿关节炎发病机制中的意义

B淋巴细胞活化和生存在类风湿关节炎(RA)病程中起关键作用。肿瘤坏死因子家族B细胞活化因子(BAFF)是维持B细胞功能的重要细胞因子。BAFF与其受体BAFF-R结合(BAFF/BAFF-R),能够激活PI3K/Akt/mTOR信号通路,调节B淋巴细胞的增殖、存活和活化。该文就B淋巴细胞、BAFF/BAFF-R以及PI3K/Akt/mTOR信号通路参与RA的发病机制加以综述。     

PI3K/Akt/mTOR信号通路与肿瘤

在近年来的肿瘤治疗中,靶向生物治疗逐渐成为研究的热点。该文就磷脂酰肌醇3-激酶/蛋白激酶B/哺乳动物雷帕霉素靶蛋白[phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt)/the mammalian target of Rapamycin(mTOR),PI3K/Akt/mTOR]信号通路予以综述,重点包括PI3K/Akt/mTOR信号转导在肿瘤机制中作用以及肿瘤治疗过程中耐药性方面的关系等。     

The PI3K/Akt/mTOR pathway: A potential pharmacological target in COVID-19

Coronavirus disease 2019 (COVID-19) has emerged as a serious threat to global health. The disregulation of the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) cell signaling pathway observed in patients with COVID-19 has attracted attention for the possible use of specific inhibitors of this pathway for the treatment of the disease. Here, we review emerging data on the involvement of the PI3K/Akt/mTOR pathway in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the clinical studies investigating its tailored inhibition in COVID-19. Current in silico, in vitro, and in vivo data convergently support a role for the PI3K/Akt/mTOR pathway in COVID-19 and suggest the use of specific inhibitors of this pathway that, by a combined mechanism entailing downregulation of excessive inflammatory reactions, cell protection, and antiviral effects, could ameliorate the course of COVID-19.     

Urolithin A suppresses tumor progression and induces autophagy in gastric cancer via the PI3K/Akt/mTOR pathway

Urolithin A (UA) is a microbial metabolite of natural polyphenols ellagitannins and ellagic acid with well-established antitumor properties against various malignancies. However, the exact role of UA in gastric cancer (GC) progression remains largely unclear. In the present study, we investigated the effects and potential mechanisms of UA in GC in vitro and in vivo. Our results revealed that UA could suppress GC cell proliferation, inhibit migration and invasion, promote apoptosis, and induce autophagy via the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathway in vitro. The autophagy inhibitors 3-methyladenine and chloroquine augmented the inhibitory effect of UA on proliferation and promoted apoptosis, implying that UA mediated the cytoprotective role of autophagy. Meanwhile, the in vivo experiments showed that UA effectively suppressed tumor growth, enhanced the therapeutic effects, and alleviated chemotherapy toxicity in xenograft models. Overall, these findings offer novel insights into the role of UA in tumor therapy and suggest that UA may possess potential therapeutic applications for GC.     

PI3K/Akt/mTOR通路在炎症相关疾病中分子机制研究进展

炎症是一种机体应对感染、组织损伤或者细胞应激的反应,并且可以通过修复机制恢复组织功能。炎症发生时会引起多条信号通路的激活,包括核转录因子-κB（NF-κB）通路、Janus激酶/信号转导与转录激活子（JAK/STAT）通路、丝裂原活化蛋白激酶（MAPK）通路以及磷脂酰肌醇-3-激酶/蛋白激酶B /雷帕霉素靶蛋白（PI3K/Akt/mTOR）通路等。本文综述了近年来磷脂酰肌醇-3-激酶/蛋白激酶B /雷帕霉素靶蛋白通路在炎症相关疾病中的分子作用机制,为研发以磷脂酰肌醇-3-激酶/蛋白激酶B /雷帕霉素靶蛋白为靶点的药物提供理论依据。     

PI3K/Akt/mTOR信号传导通路与前列腺癌关系的研究进展

前列腺癌是威胁中老年男性健康的常见肿瘤,成为男性癌症死因的第二位。 PI3K/Akt/mTOR信号通路能够通过维持细胞生存、抑制细胞凋亡、促进细胞周期运行及血管生成等促进前列腺癌病程发展。本文综合国内外文献,阐述PI3K/Akt/mTOR信号通路在前列腺癌发生发展中的作用以及和通路相关的药物治疗进展。     

基于ROS/PI3K/Akt/mTOR信号通路探讨玫瑰花甲醇提取物对前列腺癌PC-3细胞凋亡的影响

目的：探讨玫瑰花甲醇提取物（RE）对前列腺癌PC-3细胞增殖和凋亡的影响及潜在作用机制。方法：采用CCK8法检测不同浓度RE对PC-3细胞增殖的影响;采用Hoechst染色法和Annexin V/PI双染法检测细胞凋亡;DCFH-DA检测细胞ROS水平;Western blot法检测Bax、Bcl-2、cleaved caspase-3、Cyt-C、PI3K、p-PI3K、Akt、p-Akt、mTOR、p-mTOR的蛋白表达。结果：RE呈浓度依赖性抑制前列腺癌PC-3细胞增殖,24 h和48 h后的IC₅₀值分别为31.30 mg·mL^-1和16.76 mg·mL^-1;RE能显著诱导PC-3细胞凋亡（P<0.05,P<0.01）,且呈现浓度依赖性;RE可显著提高PC-3细胞ROS水平（P<0.05,P<0.01）,且具有浓度依赖性;RE能显著上调PC-3细胞Bax、cleaved caspase-3、Cyt-C的蛋白表达及Bax/Bcl-2的比值（P<0.05,P<0.01）,显著下调Bcl-2、p-PI3K、p-Akt、p-mTOR的蛋白表达（P<0.05,P<0.01）,以上均呈现浓度依赖性。结论：本研究表明RE在体外有明显抑制前列腺癌细胞PC-3的增殖作用,并可能通过调控ROS/PI3K/Akt/mTOR信号通路诱导其凋亡,研究结果可为玫瑰花及其组方临床治疗前列腺癌提供实验依据。     

紫草素抑制PI3K/Akt/mTOR信号通路诱导人结肠癌SW480细胞凋亡和自噬的作用研究

目的 探讨紫草素对人结肠癌SW480细胞凋亡和自噬的影响及其机制。方法 取对数生长期人结肠癌SW480细胞,设对照组（DMSO）、紫草素（0.3、0.5、0.7 μg/mL）和LY294002（PI3K特异性抑制剂,5 μg/mL）组。药物干预48 h后,四甲基偶氮唑盐（MTT）法检测SW480细胞增殖抑制率,Annexin V-FITC流式细胞术分析细胞凋亡状况,蛋白免疫印迹法（Western blotting）检测p-PI3K、p-Akt、p-mTOR、Caspase-3、cleaved Caspase-3、Bcl-2、Bax、LC3蛋白表达并计算Bax/Bcl-2和LC3-II/LC3-I值。结果 与对照组比较,经紫草素0.3、0.5、0.7 μg/mL或LY294002 5 μg/mL干预能够显著提高人结肠癌SW480细胞增殖抑制率和凋亡率（P<0.01）;经紫草素0.5、0.7 μg/mL或LY294002 5 μg/mL干预能够显著下调p-PI3K、p-Akt、p-mTOR、Bcl-2蛋白表达,并上调Caspase-3、cleaved Caspase-3、Bax蛋白表达（P<0.05、0.01）,提高Bax/Bcl-2和LC3-II/LC3-I值（P<0.01）。与LY294002组比较,经紫草素0.7 μg/mL干预能够显著提高SW480细胞增殖抑制率和凋亡率（P<0.05、0.01）,下调p-PI3K、p-Akt、p-mTOR蛋白表达并上调Caspase-3、cleaved Caspase-3、Bax蛋白表达（P<0.05、0.01）,提高Bax/Bcl-2和LC3-II/LC3-I值（P<0.01）。结论 紫草素能够促进人结肠癌SW480细胞凋亡和自噬,作用机制可能与抑制PI3K/Akt/mTOR信号通路活化有关。     

PI3K/Akt/mTOR,a Pathway Less Recognized for Staphylococcal Superantigen-Induced Toxicity

Immunostimulating staphylococcal enterotoxin B (SEB) and related superantigenic toxins cause diseases in humans and laboratory animals by activating cells of the immune system. These toxins bind directly to the major histocompatibility complex (MHC) class II molecules on antigen-presenting cells and specific Vβ regions of T-cell receptors (TCR), resulting in hyperactivation of both T lymphocytes and monocytes/macrophages. Activated host cells produce excessive amounts of proinflammatory cytokines and chemokines, especially tumor necrosis factor α, interleukin 1 (IL-1), IL-2, interferon γ (IFNγ), and macrophage chemoattractant protein 1 causing clinical symptoms of fever, hypotension, and shock. The well-explored signal transduction pathways for SEB-induced toxicity downstream from TCR/MHC ligation and interaction of cell surface co-stimulatory molecules include the mitogen-activated protein kinase cascades and cytokine receptor signaling, culminating in NFκB activation. Independently, IL-2, IFNγ, and chemokines from activated T cells signal via the phosphoinositide 3-kinase (PI3K), the serine/threonine kinases, Akt and mammalian target of rapamycin (mTOR) pathways. This article reviews the signaling molecules induced by superantigens in the activation of PI3K/Akt/mTOR pathways leading to staphylococcal superantigen-induced toxicity and updates potential therapeutics against superantigens.     

补骨脂素对绝经后大鼠骨质疏松及PI3K/Akt/mTOR信号通路的影响

目的:研究补骨脂素对绝经后大鼠骨质疏松及磷脂酰肌醇3激酶(PI3K)/蛋白激酶B(Akt)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路的影响。方法:将60只健康雌性SD大鼠随机分为正常组、模型组、阳性对照组(0.09 mg/kg雌二醇)和补骨脂素低、中、高剂量组(22、44、88 mg/kg),每组10只。除正常组外,其余各组大鼠均采用卵巢摘除去势法建立绝经后骨质疏松模型。术后正常饲养2个月,正常组和模型组大鼠灌胃等体积生理盐水,各药物组大鼠灌胃相应药液;灌胃体积均为0.005 mL/g,每天1次,连续98天。末次给药24 h后,测定大鼠右侧下肢股骨和椎骨的骨密度,血清中钙离子、骨钙素、Ⅰ型前胶原N端前肽(P1NP)含量和骨形态发生蛋白2(BMP2)、血管内皮生长因子(VEGF)水平,以及股骨组织中PI3K、Akt、mTOR mRNA及蛋白的表达水平。结果:与正常组比较,模型组大鼠股骨和椎骨的骨密度以及血清中钙离子、骨钙素、P1NP含量和BMP2、VEGF水平均显著降低,PI3K、Akt、mTOR mRNA及蛋白的表达水平均显著升高(P<0.05或P<0.01)。与模型组比较,补骨脂素中、高剂量组和阳性对照组大鼠股骨和椎骨的骨密度以及血清中钙离子、骨钙素、P1NP含量和BMP2(补骨脂素中剂量组除外)、VEGF(补骨脂素中剂量组除外)水平均显著升高,各药物组PI3K、Akt、m TOR mRNA(补骨脂素低剂量组除外)及蛋白表达水平均显著降低(P<0.05或P<0.01),且高剂量组股骨骨密度和钙离子、BMP2水平以及PI3K蛋白表达水平均显著高于阳性对照组(P<0.05),mTOR mRNA表达水平显著低于阳性对照组(P<0.05)。结论:补骨脂素可改善绝经后大鼠的骨质疏松,其机制可能与抑制PI3K/Akt/mTOR信号通路有关。     

磷脂酰肌醇-3磷酸激酶/AKT/雷帕霉素靶蛋白信号通路参与中枢神经损伤保护与修复的研究进展

中枢神经细胞对各种损伤刺激耐受差,损伤后神经修复困难.因此促进神经保护增强神经再生能力已成为神经治疗关键.磷脂酰肌醇-3磷酸激酶/AKT/雷帕霉素靶蛋白(PI3K/AKT/mTOR)信号通路是调节细胞周期的重要通路,在细胞增殖、生长、分化过程中起中心调控作用,在神经损伤过程中通过激活PI3K/AKT/mTOR信号通路可减少神经细胞死亡,促进神经修复.该文对PI3K/AKT/mTOR信号通路在中枢神经损伤保护作用、修复机制及可能风险作一综述,探讨将PI3K/AKT/mTOR信号通路作为靶点治疗中枢神经疾病.     

丹参酮IIA通过调控PI3K/Akt/mTOR信号通路对食管癌细胞放疗敏感性的影响

目的 研究丹参酮II_A对人食管癌细胞放疗敏感性的影响,并基于磷脂酰肌醇3激酶/蛋白激酶B/哺乳动物雷帕霉素靶蛋白（PI3K/Akt/mTOR）信号通路探讨其潜在机制。方法 以人食管癌Eca-109细胞为受试细胞,分别采用不同浓度丹参酮II_A和不同放射剂量处理Eca-109细胞,48 h后MTT法检测细胞增殖活力,计算丹参酮II_A半数抑制浓度（IC₅₀）和放射的IC₅₀,分别作为后续实验丹参酮II_A浓度和放射剂量。取对数生长期Eca-109细胞,设对照组、丹参酮II_A组、放射组、丹参酮II_A＋放射组、丹参酮II_A＋放射＋PI3K抑制剂（LY294002）组。通过平板克隆实验、MTT法、流式细胞术、荧光质粒转染法检测细胞克隆形成能力、增殖活力、凋亡率和自噬状况,RT-PCR、Western blotting法检测细胞中PI3K/Akt/mTOR信号通路相关mRNA和蛋白表达。结果 丹参酮Ⅱ_A和放射对人食管癌Eca-109细胞增殖活力的抑制作用均呈现剂量相关性,丹参酮II_A IC₅₀为8.75 mmol/L,放射量IC₅₀为4.63 Gy。与对照组相比,丹参酮II_A组、放射组、丹参酮II_A＋放射组、丹参酮II_A＋放射＋LY294002组细胞克隆形成能力和增殖活力明显降低,凋亡率和自噬体数量明显升高（P＜0.05）;PI3K、Akt、mTOR mRNA和蛋白表达量明显降低（P＜0.05）;Bcl-2、Bax、cleaved Caspase-3、LC3-I、LC3-II蛋白表达量及Bax/Bcl-2、Cleaved Caspase-3/Caspase-3、LC3-II/LC3-I明显升高（P＜0.05）。与丹参酮II_A组或放射组相比,丹参酮II_A＋放射组和丹参酮II_A＋放射＋LY294002组对各检测指标的调控作用明显增强（P＜0.05）。与丹参酮II_A＋放射组相比,丹参酮II_A＋放射＋LY294002组对各指标的调控作用明显增强（P＜0.05）。结论 丹参酮II_A可能通过下调PI3K/Akt/mTOR信号通路,抑制细胞增殖并促进其凋亡与自噬,进而增强人食管癌细胞放疗敏感性。     

Targeting the PI3K/AKT/mTOR signaling network in acute myelogenous leukemia

Background: The PI3K/Akt/mammalian target of rapamycin (mTOR) signaling pathway plays a central role in cell growth, proliferation and survival not only under physiological conditions but also in a variety of tumor cells. Therefore, the PI3K/Akt/mTOR axis may be a critical target for cancer therapy. Objective: This review discusses how PI3K/Akt/mTOR signaling network is constitutively active in acute myelogenous leukemia (AML), where it strongly influences proliferation, survival and drug-resistance of leukemic cells, and how effective targeting of this pathway with pharmacological inhibitors, used alone or in combination with existing drugs, may result in suppression of leukemic cell growth, including leukemic stem cells. Methods: We searched the literature for articles dealing with activation of this pathway in AML and highlighting the efficacy of small molecules directed against the PI3K/Akt/mTOR signaling cascade. Conclusions: The limit of acceptable toxicity for standard chemotherapy has been reached in AML. Therefore, new therapeutic strategies are needed. Targeting the PI3K/Akt/mTOR signaling network with small molecule inhibitors, alone or in combinations with other drugs, may result in less toxic and more efficacious treatment of AML patients. Efforts to exploit selective inhibitors of the PI3K/Akt/mTOR pathway that show effectiveness and safety in the clinical setting are currently underway.     

MicroRNA-141通过PI3K/Akt/mTOR信号通路促进PCOS卵巢颗粒细胞增殖的机制研究

目的　研究microRNA-141（miR-141）对卵巢颗粒细胞增殖的影响,并探讨其在多囊卵巢综合征（PCOS）发生发展中的作用机制。方法　采用实时荧光定量PCR检测20例PCOS患者的卵巢组织、20例对照组的正常卵巢组织、人卵巢颗粒细胞KGN及人正常卵巢上皮细胞IOSE80中miR-141 mRNA表达水平;KGN细胞分为miR-141 minics组、LY294002+miR-141 minics组、雷帕霉素（rapamycin）+miR-141 minics组、NC组、对照组。采用MTT法和平板克隆实验检测各组细胞增殖和克隆形成能力,采用Western blot法检测各组细胞磷脂酰肌醇3-激酶（PI3K）/蛋白激酶（Akt）/哺乳动物雷帕霉素靶蛋白（mTOR）信号通路相关蛋白表达水平。结果　PCOS卵巢组织miR-141 mRNA表达水平显著高于正常卵巢组织,人卵巢颗粒细胞KGN miR-141 mRNA表达水平高于人正常卵巢上皮细胞IOSE80（P＜0.05）;miR-141 minics组、LY294002+miR-141 minics组及rapamycin+miR-141 minics组miR-141 mRNA表达水平均高于NC组和对照组（P＜0.05）;LY294002+miR-141 minics组及rapamycin+miR-141 minics组转染后24、48、72、96 h OD值和克隆形成率均低于miR-141 minics组,但高于NC组和对照组（P＜0.05）;LY294002+miR-141 minics组转染后p-Akt、p-mTOR蛋白表达水平低于miR-141 minics组,但高于NC组、对照组（P＜0.05）。rapamycin+miR-141 minics组转染后p-mTOR蛋白表达水平低于miR-141 minics组,高于NC组、对照组（P＜0.05）。结论　miR-141可通过激活PI3K/Akt/mTOR信号通路促进卵巢颗粒细胞的增殖。     

PI3K/AKT/mTOR信号通路抑制剂在卵巢癌治疗中的研究进展

卵巢癌是女性生殖系统最致命的恶性肿瘤。目前,针对卵巢癌的规范治疗方案是肿瘤细胞减灭术辅以紫杉醇/铂类联合化疗,然而大多数晚期卵巢癌患者最终因对化疗药物耐药而复发。PI3K/AKT/m TOR信号通路作为一条重要的原癌基因通路,在卵巢癌中激活并在卵巢癌的增殖、侵袭、细胞周期进程、血管形成及耐药中发挥着重要的作用,抑制该通路是卵巢癌的一个潜在治疗方法。对PI3K/AKT/m TOR信号通路抑制剂在卵巢癌治疗中的研究进展进行综述。     

Urantide对大鼠心肌缺血/再灌注后心肌细胞凋亡的作用及机制研究

目的观察urantide对大鼠缺血/再灌注心肌组织氧化应激损伤的作用和心肌细胞凋亡的影响及其与PI3K/Akt及PKC信号通路的关系。方法可逆性冠脉左前降支结扎造成心肌缺血/再灌注模型,给予大鼠心脏缺血30 min再灌注90 min。80只大鼠随机分为假手术组、缺血/再灌注(I/R)组、urantide低、中、高剂量组(3,10,30μg.kg-1)、维拉帕米对照组(1.6 mg.kg-1)、urantide+CHE组(30μg.kg-1+1 mg.kg-1)、urantide+LY294002组(30μg.kg-1+0.3 mg.kg-1)。Urantide低、中、高剂量组中urantide于缺血前5 min舌下静脉1 min内一次性推注,urantide+CHE组与urantide+LY294002组中,在穿线稳定后舌下静脉分别快速推注CHE与LY294002,5 min后舌下静脉快速推注uran-tide 30μg.kg-1,稳定10 min后再行缺血/再灌注操作。实验结束后测定大鼠血清中超氧化物歧化酶(SOD)、一氧化氮合酶(NOS)活力和丙二醛(MDA)含量以及一氧化氮(NO)含量。TUNEL法检测凋亡细胞指数(AI),免疫组化法检测心肌组织Bcl-2、Bax的蛋白表达。结果与I/R组相比,urantide 30μg.kg-1能明显升高SOD活性(P<0.01),明显减少血清中MDA的含量(P<0.05),明显提高NOS活力(P<0.01),使NO含量增加(P<0.01);Bax蛋白表达和心肌细胞凋亡指数降低(P<0.01),Bcl-2蛋白表达增加(P<0.05);urantide+CHE组与urantide+LY294002组与urantide30μg.kg-1组相比,SOD活力和NO含量下降,MDA含量上升,心肌组织中Bax蛋白表达和心肌细胞凋亡指数上升,而Bcl-2蛋白表达下降,与I/R组比较差异无统计学意义(P>0.01)。结论 Urantide能够通过激活PKC和PI3K/Akt信号转导通路,减少心肌组织氧自由基的含量,进一步调控Bcl-2和Bax蛋白的表达,抑制心肌缺血/再灌注大鼠心肌细胞的凋亡,从而对大鼠心肌缺血/再灌注具有一定保护作用。     

Investigational PI3K/AKT/mTOR inhibitors in development for endometrial cancer

Introduction: Endometrial cancer (EC) is the most common neoplasm of the female genital tract in developed countries. Despite the progress in early detection and treatment, a significant number of cases of advanced ECs are still diagnosed. These patients have few treatment options and a poor prognosis. Our understanding of EC pathogenesis and progression has been enhanced by recent genomic studies. Among the relevant biological pathways, phosphatidylinositol 3-kinase/AKT (PIK3/AKT)-mammalian target of rapamycin (mTOR) signaling is frequently upregulated in this cancer.

Areas covered: This review covers investigational EC therapeutics acting on the PI3K/AKT/mTOR pathway. The authors review the results of clinical studies and highlight ongoing trials.

Expert opinion: Several new agents are under evaluation for treating patients with metastatic, recurrent, and persistent EC. Clinical trials investigating PI3K/AKT/mTOR inhibitors have yielded controversial results. In the near future, new studies with dual inhibitors or multi-pathways inhibitors as mono or combination therapies with conventional chemotherapy (CT) or other targeted drugs may provide more promising data. Moreover, the evaluation of new serum and histological biomarkers is an attractive strategy for patient selection.     

姜黄素通过抑制PI3K/Akt/mTOR通路增强自噬保护帕金森病细胞模型的研究

目的 观察姜黄素对帕金森病（Parkinson’s disease,PD）细胞模型中磷脂酰肌醇-3-激酶（phosphatidylinositol-3-kinase,PI3K）/蛋白激酶B （protein kinase B,Akt）/哺乳动物雷帕霉素靶蛋白（mammalian target of rapamycin,mTOR）通路的影响,并探讨其是否通过抑制此通路来增强自噬而发挥神经保护作用。方法 采用1-甲基-4-苯基-四氢吡啶离子处理人神经母细胞瘤SH-SY5Y细胞建立PD细胞模型,设立对照组、模型组、姜黄素组、姜黄素+胰岛素样生长因子1（insulin-like growth factor 1,IGF-1）组、姜黄素+LY294002组,分别应用姜黄素、姜黄素联合PI3K通路激活剂IGF-1、姜黄素联合PI3K通路抑制剂LY294002进行干预处理。各组细胞在药物处理24 h后分别于光学显微镜下观察细胞形态,细胞计数试剂盒检测细胞活力,酪氨酸羟化酶免疫荧光染色观察多巴胺（dopamine,DA）能神经元存活数目,Western blotting检测PI3K、磷酸化-Akt （phospho-Akt,p-Akt）、磷酸化-mTOR （phospho-mTOR,p-mTOR）、α-突触核蛋白（α-synuclein,α-Syn）和微管相关蛋白1轻链3B （microtubule-associated protein 1 light chain 3 beta,LC3B）的蛋白表达。结果 与模型组比较,姜黄素组细胞皱缩、空泡变性的状态得到改善,细胞存活率提高（P<0.05）,DA能神经元存活数目增加（P<0.01）,LC3B-II/LC3B-I比值增加（P<0.05）,α-Syn蛋白表达减少（P<0.01）,p-Akt、p-mTOR的蛋白表达显著下调（P<0.01）。添加PI3K通路激活剂IGF-1,姜黄素的上述作用基本被抵消;添加PI3K通路抑制剂LY294002后,与单一姜黄素干预比较,虽然LC3B-II/LC3B-I比值进一步增加（P<0.05）,但α-Syn蛋白表达增加（P<0.05）,DA能神经元存活数减少（P<0.01）。结论 在PD细胞模型中姜黄素可抑制PI3K/Akt/mTOR信号通路的活化,从而增强细胞自噬功能,继而促进α-Syn的清除是其发挥神经保护作用的主要机制之一。     

PI3K/AKT/mTOR信号通路参与脊髓损伤后神经元自噬的研究进展

PI3K/AKT/mTOR信号通路是脊髓损伤后的一条经典的自噬途径,脊髓损伤后导致的神经元细胞凋亡、轴 突脱髓鞘和炎症反应等受 PI3K/AKT/mTOR 信号通路的调控,并和神经元自噬相关。介绍脊髓损伤后 PI3K/AKT/ mTOR信号通路在神经元自噬过程中的主要作用,为进一步研究脊髓损伤提供参考。