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1.
目的 考察右美托咪定(Dex)对脂多糖(LPS)诱导的大鼠急性肺损伤(ALI)的影响,并探讨可能与PI3K/Akt信号通路改变的相关机制。方法 将80只SD大鼠根据建模方法随机分为5组:对照组、模型组、Dex低剂量组、Dex高剂量组、Dex+LY294002组,建模24 h时处死并分离肺组织,观察组织病理切片,检查肺水肿程度及微血管通透性,采用Western blotting法检测Akt及其磷酸化蛋白以及线粒体凋亡信号相关蛋白的表达水平,检查线粒体细胞色素C、膜电位及ATP含量,并用电镜观察线粒体形态,采用流式细胞术检测肺组织细胞凋亡情况,采用DCFH-DA探针荧光显微镜法检测细胞内的活性氧(ROS)水平。结果 LPS滴注24 h后,病理切片表现有明显的ALI特征,Dex在50 μg/kg剂量时可明显改善LPS诱导的ALI病理特征;以对照组为参照,p-Akt(Thr308)与p-Akt(Ser473)的相对表达量模型组未发生明显变化,Dex组则均显著增高(P<0.001),在Dex+LY294002组的表达水平较Dex组显著降低(P<0.001);模型组的Bax与Bcl-2蛋白较对照组的相对表达量分别显著升高与降低(P<0.001),Dex组分别降低与升高至接近对照组水平,Dex+LY294002组又分别回升与回降;对照组、模型组、Dex组、Dex+LY294002组的肺组织细胞凋亡率分别为2.4%、19.5%、6.7%、13.1%;各组的ROS水平变化与肺组织细胞凋亡情况一致性良好。结论 Dex可通过激活PI3K/Akt信号通路减轻LPS诱导的肺组织细胞凋亡及线粒体凋亡信号激活,继而改善ALI,发挥肺保护作用。  相似文献   

2.
《Drug discovery today》2022,27(3):848-856
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.  相似文献   

3.
Aim: NYGGF4 is a novel gene that is abundantly expressed in the adipose tissue of obese patients. The purpose of this study was to investigate the effects of NYGGF4 on basal and insulin-stimulated glucose uptake in mature 3T3-L1 adipocytes and to understand the underlying mechanisms.
Methods: 3T3-L1 preadipocytes transfected with either an empty expression vector (pcDNA3.1Myc/His B) or an NYGGF4 expression vector were differentiated into mature adipocytes. Glucose uptake was determined by measuring 2-deoxy-D- [^3H]glucose uptake into the adipocytes. Immunoblotting was performed to detect the translocation of insulin-sensitive glucose transporter 4 (GLUT4). Immunoblotting also was used to measure the phosphorylation and total protein contents of insulin signaling proteins such as the insulin receptor (IR), insulin receptor substrate (IRS)-I, Akt, ERK1/2, p38, and JNK.
Results: NYGGF4 over-expression in 3T3-L1 adipocytes reduced insulin-stimulated glucose uptake and impaired insulinstimulated GLUT4 translocation. It also diminished insulin-stimulated tyrosine phosphorylation of IRS-1 and serine phosphorylation of Akt without affecting the phosphorylation of 1R, ERK1/2, p38, and JNK.
Conclusion: NYGGF4 regulates the functions of IRS-1 and Akt, decreases GLUT4 translocation and reduces glucose uptake in response to insulin. These observations highlight the potential role of NYGGP 4 in glucose homeostasis and possibly in the pathogenesis of obesity.  相似文献   

4.
目的研究褪黑素对游离脂肪酸(FFA)诱导的胰岛素抵抗3T3-L1脂肪细胞葡萄糖摄取能力的影响。方法 "鸡尾酒"法培养诱导3T3-L1成纤维细胞分化成脂肪细胞,油红O染色鉴定脂肪细胞形态;利用棕榈酸(300μmol/L)诱导脂肪细胞的胰岛素抵抗,采用液体闪烁法检测细胞葡萄糖摄取能力;检测褪黑素对FFA处理的3T3-L1脂肪细胞的葡萄糖摄取能力的影响。结果 3T3-L1细胞经诱导分化成脂肪细胞,油红O染色呈圆形,脂滴呈典型的"戒环样"形态;用FFA处理上述细胞6 h后,细胞的葡萄糖摄取能力明显降低;褪黑素可以促进FFA处理的3T3-L1脂肪细胞胰岛素介导的葡萄糖摄取。结论 FFA可以降低胰岛素诱导的体外培养的脂肪细胞葡萄糖摄取能力,可能是胰岛素抵抗的病因之一。褪黑素可以干预FFA的作用,增加细胞的葡萄糖摄取能力。  相似文献   

5.
In order to identify whether bisphenol A (BPA) acts as an adipogenic agent, following the hormonal induction of differentiation into adipocytes, 3T3-L1 cells were treated for six days with BPA alone. Treatment with BPA increased the triacylglycerol (TG) content of the cultures, increased the percentage of Oil Red O-staining cells in the cultures, and increased the levels of lipoprotein lipase (LPL) and adipocyte-specific fatty acid binding protein (aP2) mRNAs. These findings indicate that BPA was able to accelerate terminal differentiation of 3T3-L1 cells into adipocytes. LY294002, a chemical inhibitor of phosphatidylinositol 3-kinase (PI 3-kinase), blocked completely the increasing effect of BPA on TG accumulation and expression of LPL and aP2 mRNAs. Western blot analysis revealed that BPA increased the level of phosphorylated Akt kinase. Based on these findings, we concluded that BPA acted through the PI 3-kinase and Akt kinase pathway, resulting in increased TG accumulation and expression of adipocyte genes. The structure-activity relationship for BPA-related chemicals was examined. Eight derivatives of BPA (three diphenylalkanes with different substituents at the central carbon atom, three diphenylalkanes with ester bonds on hydroxyl groups in the phenolic rings, one bisphenol consisting of a sulphur atom at the central position, one chemical with cyanic groups, instead of hydroxyl groups, in the phenolic rings) accelerated terminal adipocyte differentiation and their potencies to increase TG accumulation were 73-97% of that of BPA. Two diphenylalkanes with ether bonds on hydroxyl groups and two alkylphenols (4-nonylphenol and 4-tert-octylphenol) did not have the ability to accelerate terminal adipocyte differentiation.  相似文献   

6.
目的 通过磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)信号通路探讨牡荆素对脑外伤大鼠的神经保护作用。方法 选用SD大鼠90只,随机分成假手术组,模型组,牡荆素假手术组(12 mg/kg牡荆素),牡荆素低(3 mg/kg牡荆素)、高剂量组(12 mg/kg牡荆素)和吡拉西坦组(20 mg/kg吡拉西坦),每组18只。采用自由落体致伤法建立脑外伤大鼠模型;采用神经功能评分法评价神经功能缺损程度;测定脑组织的含水量;苏木素伊红(HE)染色检测脑组织病理变化;TUNEL法检测脑组织神经细胞的凋亡情况;ELISA法检测脑组织丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)水平;Western blotting法检测脑组织中PI3K、p-PI3K、Akt、p-Akt、mTOR、p-mTOR蛋白水平。结果 与假手术组相比,模型组大鼠神经元变性坏死,毛细血管破裂,可见大量出血、炎性细胞浸润,神经功能受损评分、细胞凋亡指数、脑组织含水量及MDA含量显著升高(P<0.05),SOD、GSH-Px含量及p-PI3K、p-Akt、p-mTOR蛋白水平显著降低(P<0.05)。与模型组相比,牡荆素低、高剂量组和吡拉西坦组大鼠病理变化均有一定程度减轻,神经功能受损评分、细胞凋亡指数、脑组织含水量及MDA含量显著降低(P<0.05),SOD、GSH-Px含量及p-PI3K、p-Akt、p-mTOR蛋白水平均显著升高(P<0.05)。假手术组和牡荆素假手术组各项指标差异无统计学意义。牡荆素高剂量组和吡拉西坦组各项指标差异无统计学意义。结论 牡荆素可能通过激活PI3K/Akt信号通路,发挥脑外伤大鼠的神经保护作用。  相似文献   

7.
嵇莹莹  龚国清 《药学研究》2018,37(4):226-229
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。  相似文献   

8.
Acute myocardial ischaemia/reperfusion (MIR) injury leads to severe arrhythmias and has a high rate of lethality. In the present study, we aim to determine the effect of dexmedetomidine (Dex) on heart injury parameters following MIR surgery. We examined the effects of Dex on heart function parameters and infarct size following MIR surgery. Proinflammatory cytokines, oxidative products and anti‐oxidative enzymes in the myocardium were measured to evaluate the anti‐inflammatory and anti‐oxidative effects of Dex. The role of the adenosine 5′‐monophosphate (AMP)‐activated protein kinase (AMPK)/phosphatidylino‐sitol 3‐kinase (PI3k)/Akt/endothelial nitric oxide synthase (eNOS) pathway was investigated using their inhibitors. The alteration of haemodynamic parameters, histopathological results, and infarct size caused by MIR was attenuated by Dex. The interleukine‐1 beta (IL‐1β), IL‐6, tumour necrosis factor‐a (TNF‐α) and myeloperoxidase (MPO) were all significantly decreased. Anti‐oxidative enzymes superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) were restored by Dex. Oxidative products8‐OHdG, MDA and protein carbonyl were all decreased by Dex (P<.05). Dex activated AMPK expression, eNOS and Akt phosphorylation. The influence of Dex on cardiac function was reversed by the inhibitors of the eNOS, AMPK and PI3K/Akt pathways. These results indicate that Dex protected the cardiac functional, histological changes, inflammation and oxidative stress induced by MIR. Our results present a novel signalling mechanism that Dex protects MIR injury by activating an AMPK/PI3K/Akt/eNOS pathway.  相似文献   

9.
10.
目的 探讨脂肪因子Apelin-13对3T3-L1脂肪细胞水通道蛋白7(AQP7)基因表达的影响.方法 体外培养3T3-L1脂肪细胞,以油红O染色鉴定为成熟脂肪细胞后,分为阴性对照组(无干预),不同浓度(10^-9、10^-8、10^-7、10^-6nmol/L) Apelin-13干预组(均干预24 h),阳性对照组(10^-5 nmol/L罗格列酮干预24 h)和10^-7 nmol/L Apelin-13干预不同时间(0、12、24、36、48 h)组.用反转录-聚合酶链反应检测各组细胞AQP7 mRNA表达水平.结果 阴性对照组、10^-9、10^-8、10^-7、10^-6 nmol/L Apelin-13和阳性对照组AQP7表达水平分别为(0.22±0.02)、(0.29±0.07)、(0.36±0.05)、(0.43±0.05)、(0.31±0.06)、(0.32±0.08),阳性对照组与阴性对照组之间差异有统计学意义(P<0.05);与阴性对照组比较,10^-8、10^-7 nmol/L Apelin-13能明显刺激AQP7 mRNA表达(P <0.05);10^-8、10^-7 nmol/L Apelin-13组与阳性对照组比较,10^-7 nmol/L Apelin-13能明显刺激AQP7 mRNA表达(P<0.05);10^-8、10^-7 nmol/L Apelin-13组间差异无统计学意义.在时间组中,10^-7 nmol/L Apelin-13的0、12、24、36、48 h各组灰度比值分别为(0.27±0.09)、(0.43±0.07)、(0.55±0.10)、(0.42±0.08)、(0.33±0.09),12、24、36 h组AQP7 mRNA表达较0h组能明显刺激AQP7 mRNA表达(P<0.05),作用24 h表达最高;但12、24、36h3组之间AQP7mRNA表达差异无统计学意义.结论 Apelin-13在一定程度上能增加3T3-L1脂肪细胞AQP7 mRNA表达的水平,并分别以10^-7 nmol/L和24 h为最佳作用浓度和时间.  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
Isoflurane, a common volatile anesthetic, has been widely used to provide general anesthesia in operations. However, exposure to isoflurane may cause widespread neurotoxicity in the developing animal brain. Fraxetin, a natural coumarin derivative extracted from the bark of Fraxinus rhynchophylla, possesses versatile pharmacological properties including anti-oxidative, anti-inflammatory, and neuroprotective effects. However, the effect and action mechanism of fraxetin on neurotoxicity induced by isoflurane are unknown. Reactive oxygen species (ROS) generation, cell viability, lactate dehydrogenase (LDH) release, and apoptosis were estimated by 2′,7′-dichlorofluorescin-diacetate (DCFH-DA) staining, MTT, LDH release, and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) staining assays, respectively. The protein levels of light chain 3 (LC3)-I, LC3-II, p62, protein kinase B (Akt), and phosphorylated Akt (p-Akt) were detected by western blot analysis. Isoflurane induced ROS, LDH release, apoptosis, and autophagy, but inhibited the viability in HT22 cells, which were overturned by fraxetin or ROS scavenger N-acetyl-L-cysteine. Fraxetin suppressed isoflurane-induced PI3K/Akt inactivation in HT22 cells. PI3K/Akt inactivation by LY294002 resisted the effects of fraxetin on isoflurane-induced autophagy and autophagy-modulated neurotoxicity in HT22 cells. In conclusion, fraxetin suppressed ROS-dependent autophagy by activating the PI3K/Akt pathway to inhibit isoflurane-induced neurotoxicity in hippocampal neuronal cells.  相似文献   

14.
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。  相似文献   

15.

Aim:

To investigate whether nerve growth factor (NGF) induced angiogenesis of bone marrow mesenchymal stem cells (MSCs) and the underlying mechanisms.

Methods:

Bone marrow MSCs were isolated from femors or tibias of Sprague-Dawley rat, and cultured. The cells were purified after 3 to 5 passages, seeded on Matrigel-coated 24-well plates and treated with NGF. Tube formation was observed 24 h later. Tropomyosin-related kinase A (TrkA) and p75NTR gene expression was examined using PCR analysis and flow cytometry. Growth curves were determined via cell counting. Expression of VEGF and pAkt/Akt were analyzed with Western blot.

Results:

NGF (25, 50, 100 and 200 μg/L) promoted tube formation of MSCs. The tubular length reached the maximum of a 2.24-fold increase, when the cells were treated with NGF (50 μg/L). NGF (50 μg/L) significantly enhanced Akt phosphorylation. Pretreatment with the specific PI3K inhibitor LY294002 (10 μmol/L) blocked NGF-stimulated Akt phosphorylation, tube formation and angiogenesis. NGF (25–200 μg/L) did not affect the expression of TrkA and vascular endothelial growth factor (VEGF), but significantly suppressed the expression of p75NTR. NGF (50 μg/L) markedly increased the proliferation of MSCs.

Conclusion:

NGF promoted proliferation of MSCs and activated the PI3K/Akt signaling pathway, which may be responsible for NGF induction of MSC angiogenesis.  相似文献   

16.
17.
In this study, we investigated the effect of sulfated glucosamine (SGlc) on adipogenesis of 3T3-L1 adipocytes during differentiation of preadipocytes into adipocytes by measuring lipid accumulation and adipogenesis related factors. Treatment with SGlc reduced the triglyceride content in Oil-Red O staining and enhanced glycerol secretion in adipocytes in a dose-dependent manner. In addition, SGlc induced the down-regulation of adipogenesis related factors and adipocyte specific gene promoters. Moreover, treatment of 3T3-L1 adipocytes with SGlc activated the phosphorylated adenosine monophosphate-activated protein kinase (AMPK) α and β along with their substrate, acetyl-CoA carboxylase (ACC). These results suggest that inhibitory effect of SGlc on adipocyte differentiation might be mediated through the up-regulation of AMPK pathway.  相似文献   

18.
PI3K/Akt/mTOR信号通路与肿瘤   总被引:1,自引:0,他引:1  
张丹丹  李庆林 《安徽医药》2012,16(3):281-283
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。  相似文献   

19.
Dysregulated follicular development may lead to follicular atresia, and this is associated with oxidative stress in granulosa cells. Kurarinone is a natural compound possessing multiple activities, including antioxidative ability. However, the role of kurarinone in granulosa cell damage during follicular atresia remains unknown. Human ovarian granulosa KGN cells were treated with hydrogen peroxide (H2O2) to induce cellular damage. Cytotoxicity was investigated by lactate dehydrogenase (LDH) release assay. Oxidative stress was evaluated by detection of reactive oxygen species (ROS) generation and oxidative biomarker levels. Cell apoptosis was evaluated by flow cytometry, a Cell Death Detection ELISA Kit, and a Caspase-3 Assay Kit. The downstream target and related signaling pathway were analyzed by western blotting. Kurarinone attenuated H2O2-induced LDH release in KGN cells. Kurarinone relieved H2O2-induced increase in ROS generation and malondialdehyde level as well as decrease in superoxide dismutase-1 activity and heme oxygenase 1 and NAD(P)H quinone dehydrogenase 1 mRNA levels. Kurarinone inhibited H2O2-induced apoptosis in KGN cells. Kurarinone targeted insulin-like growth factor 1 (IGF1) and upregulated IGF1 expression to activate the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling. IGF1 silencing attenuated the suppressive effects of kurarinone on H2O2-induced oxidative stress and apoptosis in KGN cells. In conclusion, kurarinone attenuates H2O2-induced oxidative stress and apoptosis in KGN cells through activating the PI3K/Akt signaling by upregulating IGF1 expression, indicating the therapeutic potential of kurarinone in follicular atresia.  相似文献   

20.
目的 研究五味子乙素联合泼尼松对膜性肾病大鼠的作用及对其对PI3K/Akt信号通路的影响。方法 取15只SD大鼠作为对照组,60只大鼠采用阳离子化牛血清白蛋白(C-BSA)建立膜性肾病模型,造模完成后的大鼠随机分为模型组、泼尼松(2 mg/kg)组、五味子乙素(30 mg/kg)组、五味子乙素(30 mg/kg) +泼尼松(2 mg/kg)组。连续给药28 d后,分别测定各组大鼠24 h尿蛋白量、血清总胆固醇(TC)、三酰甘油(TG)、丙二醛(MDA)、超氧化物歧化酶(SOD)、尿素氮(BUN)及肌酐(Scr)水平,苏木精-伊红染色法进行组织病理学检查,Western blotting法检测大鼠肾脏p-Akt、Akt、PI3K-P85、PI3K-P110蛋白表达水平。结果 与模型组比较,泼尼松组、五味子乙素组、五味子乙素+泼尼松组大鼠24 h尿蛋白量和血清TC、TG、MDA、BUN及Scr水平均显著降低(P<0.05),SOD水平显著升高(P<0.05),组织病理学明显改善,肾脏p-Akt、Akt、PI3K-P85、PI3K-P110蛋白表达水平均显著降低(P<0.05),且五味子乙素+泼尼松组各项指标均优于单给药组。结论 五味子乙素联合泼尼松对大鼠膜性肾病发挥显著改善作用,作用优于单给药,其机制可能与调节PI3K/Akt信号通路有关。  相似文献   

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