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1.
目的探讨补阳还五汤抗大鼠脑缺血/再灌注损伤的AMPK/mTOR/ULK1自噬信号通路机制。方法用改良线栓法建造大鼠左侧脑缺血模型,各组大鼠每24 h给药1次,共3次。再灌注72 h后观察大鼠神经损伤情况和脑梗死体积改变;尼氏染色法和TUNEL染色法观察神经细胞形态、数量以及凋亡情况;Western blot检测自噬蛋白和AMPK/mTOR/ULK1自噬信号通路相关蛋白表达情况。结果补阳还五汤改善大鼠神经功能缺陷,减少脑梗死体积和神经细胞凋亡,减轻脑组织病理损伤;抑制AMPK磷酸化活化,解除AMPK对下游mTOR和ULK1的抑制,促进二者磷酸化激活,抑制细胞自噬。AMPK激动剂Metformin提高细胞自噬水平,同时逆转了补阳还五汤抗大鼠脑缺血/再灌注损伤作用。结论补阳还五汤介导AMPK/mTOR/ULK1自噬信号通路对脑缺血/再灌注损伤大鼠发挥神经保护作用。  相似文献   
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目的探究丙泊酚对子宫内膜癌细胞系RL95-2增殖和凋亡的影响,以及对mTOR/S6K1信号通路的作用。方法将RL95-2细胞分为对照组和丙泊酚组(加入不同浓度的丙泊酚)。CCK-8法检测细胞增殖;克隆形成实验检测细胞克隆形成能力;流式细胞测量术检测细胞凋亡;比色法测定细胞caspase-3和caspase-9活性;蛋白质免疫印迹法(Western blot)检测细胞蛋白激酶B(Akt)、哺乳动物雷帕霉素靶蛋白(mTOR)和核糖体蛋白S6激酶1(S6K1)磷酸化水平。结果与对照组相比,丙泊酚各组RL95-2细胞增值率和细胞克隆形成能力均显著降低(P<0.05),细胞凋亡率以及细胞caspase-3和caspase-9活性均显著升高(P<0.05),细胞p-Akt、p-mTOR和p-S6K1蛋白磷酸化水平显著降低(P<0.05)。结论丙泊酚可能通过调控mTOR/S6K1通路,抑制子宫内膜癌细胞系的增殖、促进癌细胞凋亡。  相似文献   
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目的:探究基于AMP活化蛋白激酶(AMPK)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路介导的自噬途径研究黄芪多糖(APS)对急性放射性肠炎大鼠肠黏膜的保护作用。方法:对SD大鼠进行12 Gy单次照射,制备急性放射性肠炎模型,随机分为模型组、APS(2 g/kg)组、AMPK抑制剂compound C(CC,0.2 mg/kg)组和APS(2 g/kg)+CC(0.2 mg/kg)组,每组12只;另取12只大鼠不做处理,设为对照组。以药物分组干预处理后,检测大鼠一般情况,做临床症状评分;HE染色观察大鼠肠黏膜病理形态;试剂盒检测大鼠血清白细胞介素17(IL-17)、IL-1β、肿瘤坏死因子α(TNF-α)、肠型脂肪酸结合蛋白(I-FABP)、细胞间黏附分子1(ICAM-1)和二胺氧化酶(DAO)水平;Western blot法检测大鼠肠黏膜组织自噬相关蛋白(beclin-1和LC3-II/LC3-I)及AMPK/mTOR通路相关蛋白(p-AMPK/AMPK和p-mTOR/mTOR)水平。结果:与对照组相比,模型组大鼠肠黏膜组织出现严重病理损伤,肠黏膜组织beclin-1、LC3-II/...  相似文献   
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赵玉霞  陈莺倩 《中草药》2021,52(22):6897-6903
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。  相似文献   
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Arthropod-borne flaviviruses, such as Zika virus (ZIKV), Usutu virus (USUV), and West Nile virus (WNV), are a growing cause of human illness and death around the world. Presently, no licensed antivirals to control them are available and, therefore, search for broad-spectrum antivirals, including host-directed compounds, is essential. The PI3K/Akt pathway controls essential cellular functions involved in cell metabolism and proliferation. Moreover, Akt has been found to participate in modulating replication in different viruses including the flaviviruses. In this work we studied the interaction of flavivirus NS5 polymerases with the cellular kinase Akt. In vitro NS5 phosphorylation experiments with Akt showed that flavivirus NS5 polymerases are phosphorylated and co-immunoprecipitate by Akt. Polymerase activity assays of Ala- and Glu-generated mutants for the Akt-phosphorylated residues also indicate that Glu mutants of ZIKV and USUV NS5s present a reduced primer-extension activity that was not observed in WNV mutants. Furthermore, treatment with Akt inhibitors (MK-2206, honokiol and ipatasertib) reduced USUV and ZIKV titers in cell culture but, except for honokiol, not WNV. All these findings suggest an important role for Akt in flavivirus replication although with specific differences among viruses and encourage further investigations to examine the PI3K/Akt/mTOR pathway as an antiviral potential target.  相似文献   
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《Neuro-Chirurgie》2023,69(5):101480
ObjectiveUnfavorable outcomes in patients with subarachnoid hemorrhage (SAH) are mainly attributed to early brain injury (EBI). Reduction of neuronal death can improve the prognosis in SAH patients. Autophagy and apoptosis are critical players in neuronal death. Urolithin A (UA) is a natural compound produced by gut bacteria from ingested ellagitannins and ellagic acid. Here, we detected the role of UA in EBI post-SAH.MethodsWe established an animal model of SAH in rats by endovascular perforation, with administration of UA, 3-methyladenine (3-MA) and Compound C. SAH grading, neurological function, brain water content, western blotting analysis of levels of proteins related to apoptosis, autophagy and pathways, blood-brain barrier (BBB) integrity, TUNEL staining, and immunofluorescence staining of LC3 were evaluated at 24 h after SAH.ResultsSAH induction led to neurological dysfunctions, BBB disruption, and cerebral edema at 24 h post-SAH in rats, which were relieved by UA. Additionally, cortical neuronal apoptosis in SAH rats was also attenuated by UA. Moreover, UA restored autophagy level in SAH rats. Mechanistically, UA activated the AMPK/mTOR pathway. Furthermore, inhibition of autophagy and AMPK limited UA-mediated protection against EBI post-SAHConclusionUA alleviates neurological deficits, BBB permeability, and cerebral edema by inhibiting cortical neuronal apoptosis through regulating the AMPK/mTOR pathway-dependent autophagy in rats following SAH.  相似文献   
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TP53 is the most frequently mutated gene in head and neck squamous cell carcinoma (HNSCC). Patients with HPV-negative TP53 mutant HNSCC have the worst prognosis, necessitating additional agents for treatment. Since mutant p53 causes sustained activation of the PI3K/AKT/mTOR signaling pathway, we investigated the effect of rapalogs RAD001 and CCI-779 on HPV-negative mutTP53 HNSCC cell lines and xenografts. Rapalogs significantly reduced cell viability and colony formation. Interestingly, rapalogs-induced autophagy with no effect on apoptosis. Pretreatment with autophagy inhibitors, 3-methyladenine (3-MA) and ULK-101 rescued the cell viability by inhibiting rapalog-induced autophagy, suggesting that both RAD001 and CCI-779 induce non-apoptotic autophagy-dependent cell death (ADCD). Moreover, rapalogs upregulated the levels of ULK1 and pULK1 S555 with concomitant downregulation of the mTORC1 pathway. However, pretreatment of cells with rapalogs prevented the ULK-101-mediated inhibition of ULK1 to sustained autophagy, suggesting that rapalogs induce ADCD through the activation of ULK1. To further translate our in vitro studies, we investigated the effect of RAD001 in HPV-negative mutTP53 (HN31 and FaDu) tumor cell xenograft model in nude mice. Mice treated with RAD001 exhibited a significant tumor volume reduction without induction of apoptosis, and with a concomitant increase in autophagy. Further, treatment with RAD001 was associated with a considerable increase in pULK1 S555 and ULK1 levels through the inhibition of mTORC1. 3-MA reversed the effect of RAD001 on FaDu tumor growth suggesting that RAD001 promotes ACDC in HPV-negative mutTP53 xenograft. This is the first report demonstrating that rapalogs promote non-apoptotic ADCD in HPV-negative mutTP53 HNSCC via the ULK1 pathway. Further studies are required to establish the promising role of rapalogs in preventing the regrowth of HPV-negative mutTP53 HNSCC.  相似文献   
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目的 研究GLP-1通过调控mTOR信号通路诱导的自噬对糖尿病大鼠视网膜病变是否存在保护作用。 方法 建立符合要求的糖尿病视网膜病变大鼠模型,分为模型组、胰岛素组和GLP-1组,每组6只,于造模后即刻、4周、8周、12周测定大鼠空腹血糖水平,12周后处死,取视网膜组织行HE染色,免疫组化法测LC3、P53的表达,超氧化物歧化酶法测定血清氧化应激产物ROS、MDA的含量,Western blotting法测定mTOR蛋白表达。 结果 与模型组相比,胰岛素组和GLP-1组可以明显降低空腹血糖,差异有统计学意义,而两组内比较差异无统计学意义。HE染色显示模型组视网膜神经节细胞排列紊乱,细胞减少或缺失,而胰岛素组和GLP-1组视网膜神经节细胞排列较规整,数量无明显减少,接近正常。免疫组化显示GLP-1组LC3、P53蛋白表达较其他组升高分别为(2.34±0.13,0.46±0.03),与各组比较差异均有统计学意义(P<0.05)。GLP-1组氧化应激产物ROS、MDA含量分别为(74.68±4.08,55.60±1.50),较其他组减少,各组间比较差异均有统计学意义(P<0.05)。Western blotting法测定GLP-1组mTOR蛋白含量下降(0.43±0.04),与各组间比较差异有统计学意义(F=105.447,P<0.05)。 结论 GLP-1可能通过调控mTOR信号通路,激活自噬,减少视网膜氧化应激损伤,从而达到保护视网膜的作用。  相似文献   
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