槲皮苷通过抑制PI3K/AKT信号通路诱导胃癌SGC7901细胞凋亡

目的:探讨槲皮苷是否通过抑制PI3K/AKT信号通路诱导人胃癌SGC7901细胞凋亡。方法:选取SGC7901细胞作为研究对象,采用MTT法检测槲皮苷对SGC7901细胞的毒性作用并测定IC50值。实验分为对照组(不加药处理)、槲皮苷组(采用200μmol/L槲皮苷处理)、PI3K/AKT通路激动剂胰岛素样生长因子1(IGF-1)组(采用100μg/L IGF-1处理)和槲皮苷+IGF-1组(采用200μmol/L槲皮苷+100μg/L IGF-1共处理)。处理48 h后,采用流式细胞术检测细胞凋亡,Western blot法检测cleaved caspase-3、p-AKT(Ser473)、AKT、p-PI3K(Tyr508)和PI3K的蛋白水平。结果:从100μmol/L开始,随着槲皮苷处理浓度的逐渐升高,SGC7901细胞活力显著降低(P 0. 05),槲皮苷作用48 h的IC50值为275. 40μmol/L。200μmol/L槲皮苷作用SGC7901细胞48 h后,与对照组比较,细胞凋亡率和cleaved caspase-3蛋白水平显著上升(P 0. 05),p-AKT和p-PI3K蛋白水平显著降低(P 0. 05),然而IGF-1与槲皮苷共同作用时,IGF-1可逆转槲皮苷对SGC7901细胞的作用效果。结论:槲皮苷能够诱导胃癌SGC7901细胞凋亡,其作用机制可能与抑制PI3K/AKT信号通路的激活有关。     

乌骨藤提取物通过调控PI3K/AKT/mTOR信号通路抑制黑色素瘤细胞的活力并诱导细胞凋亡

目的:探究乌骨藤提取物(Marsdenia tenacissima extract,MTE)对黑色素瘤细胞活力及凋亡的作用及机制。方法:用不同浓度(0、50、100和200 mg/L) MTE处理小鼠皮肤黑色素瘤B16-F10细胞24 h或不同浓度MTE处理不同时间(0、24、48、72和96 h),MTT法检测细胞活力。流式细胞术检测细胞凋亡情况,Western blot法检测细胞增殖、凋亡和PI3K/AKT/mTOR通路相关蛋白的表达,同时检测通路激动剂胰岛素样生长因子1(IGF-1)处理细胞后p-PI3K及细胞增殖和凋亡相关蛋白的表达。结果:根据预实验结果,选择MTE作用时间为72 h。MTE浓度为100 mg/L和200 mg/L时能明显抑制B16-F10细胞活力及增殖相关蛋白Ki67和PCNA的表达,并且还可诱导B16-F10细胞凋亡,提高凋亡相关蛋白cleaved caspase-3和cleaved caspase-9的蛋白水平;同时,MTE还可显著降低p-PI3K、p-AKT和mTOR的蛋白水平;此外,激动剂IGF-1可明显减弱MTE抑制细胞活力及诱导细胞凋亡的作用。结论:MTE可通过下调PI3K/AKT/mTOR通路活性抑制黑色素瘤细胞活力,诱导细胞凋亡。     

LINC00323 mediates the role of M1 macrophage polarization in diabetic nephropathy through PI3K/AKT signaling pathway

ObjectiveTo explore the effect of LINC00323 on the polarization of M1 macrophages in diabetic nephropathy. To study the effect and biological mechanism of LINC00323 on the occurrence and development of diabetic nephropathy.MethodsWe used clinical samples to analyze the correlation between macrophage polarization and the occurrence and development of diabetic nephropathy. In addition, we used bioinformatics to analyze the key molecules of macrophage polarization. We then verified the key pathways that promote the M1 polarization of macrophages at the level of cell biology. And we verify the effectiveness of treatment against this target in animal experiments.ResultsWe analyzed in clinical samples that the expression of inflammatory factors (TNF-α and IL-6) increased in patients with diabetic nephropathy. In addition, we found that the expression of M1 marker protein CD86 increased through PCR and western blot analysis. We found a key target (LINC00323) through bioinformatics. The expression of LINC00323 in patients' blood samples is also at a high level. We further explored the mechanism of LINC00323 involved in the polarization of M1 macrophages at the level of cellular molecular biology, and found that it is closely related to the PI3K/AKT signaling pathway. In animal models, we found that inhibiting the expression of LINC00323 can reduce the damage of diabetic nephropathy.ConclusionWe found that LINC00323 mediates the polarization of M1 macrophages through the PI3K/AKT signaling pathway. LINC00323 plays an important role in the occurrence and development of diabetic nephropathy.     

钙敏感受体通过PI3K/AKT通路对缺氧诱导的A549细胞增殖的影响

目的:探讨钙敏感受体(calcium-sensing receptor,CaSR)在缺氧诱导的A549及A549/DDP细胞增殖中的信号转导途径。方法:通过缺氧培养箱内(93%N_2、2%O_2、5%CO_2)培养24 h的方法复制细胞缺氧模型。应用Western blot技术分析PCNA及p-AKT蛋白不同处理情况下的表达水平;采用流式细胞技术检测不同处理因素对细胞周期及增殖指数的影响,应用BrdU掺入法分析不同处理因素对细胞DNA合成的影响。结果:缺氧引起A549及A549/DDP细胞PCNA及p-AKT蛋白水平上调,增加BrdU掺入量、S期细胞数量和细胞增殖指数,GdCl_3能够增强缺氧的作用,但上述效应可以被LY294002抑制。结论:PI3K/AKT信号通路在缺氧活化CaSR并促进A549及A549/DDP细胞增殖中起重要作用。     

lncRNAPVT1 targets miR-152 to enhance chemoresistance of osteosarcoma to gemcitabine through activating c-MET/PI3K/AKT pathway

Background: LncRNA PVT1 has been reported to be involved in a variety of biological processes, including cell proliferation, cell differentiation and cancer progression. However, the mechanism by which LncRNA PVT1 contributes to chemoresistance of osteosarcoma cell, has not been fully elucidated.Methods: We first generatedLncRNA PVT1-overexpressed MG63 cells and LncRNA PVT1 knockdown MG63/DOX cells. Then, we examined the effect of LncRNA PVT1 on cell viability and colony formation ability by MTT assay and soft agar assay, respectively. In addition, we performed flow cytometry analysis to detect apoptosis induced by GEM. Dual luciferase reporter assay and RIP were used to confirmed the interaction between LncRNA PVT1 and miR-152. Finally, we determined protein level of c-MET, p-PI3K, and p-AKT by westernblot.Results: LncRNA PVT1 overexpression promoted cell proliferation and exhibited the anti-apoptotic property in LncRNA PVT1-overexpressing MG63 cells treated with gemcitabine. While, LncRNA PVT1-depleted MG63/DOX cells treated with gemcitabine exhibited significant lower survival rate and high percentage of apoptosis. Next, we found that LncRNA PVT1 could target and downregulated the level of miR-152. Interestingly, miR-152 greatly rescued the biological outcomes of LncRNA PVT1 not only in MG63 but also in MG63/DOX cells. We observed that LncRNA PVT1 markedly induced PI3K/AKT pathway activation, which was abolished by miR-152 mimics overexpression. Finally, c-MET inhibitor was used to confirm the essential role of c-MET in LncRNA PVT1 and miR-152-regulated PI3K/AKT signaling.Conclusion: We showed thatlncRNA PVT1 played a contributory role in chemoresistance of osteosarcoma cells through c-MET/PI3K/AKT pathway activation, which was largely dependent on miR-152. Our findings advance our understanding of how lncRNA PVT1 promotes chemoresistance of osteosarcoma cells and facilitate development of novel strategies for treating osteosarcoma.     

M3R激动剂通过激活PI3K/AKT信号途径促进肺癌细胞A549的上皮间质转化

目的:探讨毒蕈碱胆碱受体3(muscarinic receptor 3,M3R)激动剂卡巴胆碱促进人肺癌A549细胞上皮间质转化的可能信号通路。方法:用400μmol/L卡巴胆碱刺激人肺癌A549细胞,在倒置相差显微镜下观察细胞形态的变化,应用划痕愈合实验和Transwell实验观察细胞迁移和侵袭能力;应用q PCR技术检测上皮间质转化相关蛋白波形蛋白(vimentin)和E钙黏蛋白(E-cadherin)m RNA水平的变化;应用Western blot技术检测p-AKT、vimentin和E-cadherin蛋白水平的变化。结果:卡巴胆碱刺激人肺癌A549细胞后,细胞形态发生明显改变,由不规则多边形逐渐向梭形转化、细胞间紧密结合逐渐变得松散,细胞迁移和侵袭能力增强;vimentin的m RNA和蛋白表达量明显增加,E-cadherin的m RNA和蛋白水平降低,磷酸化的AKT蛋白水平增加,且这些变化均可被M3R特异性抑制剂4-DAMP所抑制(P0.05)。结论:卡巴胆碱可通过激活PI3K/AKT信号途径促进人肺癌A549细胞发生上皮间质转化。     

PI3K/AKT信号通路在SjCystatin诱导M2巨噬细胞分化过程中的影响

目的:进一步确定日本血吸虫半胱氨酸蛋白酶抑制剂(Sj Cystatin)诱导M2巨噬细胞分化的亚型及相关机制。方法:用ELISA、RT-q PCR或Western blot法测定IL-10、IL-12、巨噬细胞亚型表面标志物LIGHT(M2b)及Arg-1(M2a+M2c)的表达;用Western blot法测定AKT的磷酸化水平。结果:Sj Cystatin处理组在6 h、12 h和24h时IL-10表达量持续增加;处理12 h,LIGHT的mRNA和蛋白表达量增加但Arg-1的mRNA和蛋白表达量降低;AKT磷酸化水平增加。PI3K/AKT抑制剂处理组IL-10的释放量在12 h和24 h持续降低;24 h,LIGHT的mRNA和蛋白表达量降低但Arg-1的mRNA和蛋白表达量增加;AKT的磷酸化水平减少。结论:Sj Cystatin促进了活化的M2巨噬细胞分化为M2b亚型巨噬细胞,并且PI3K/AKT信号通路参与了这一过程。     

MicroRNA-129-5p suppresses proliferation,migration and invasion of retinoblastoma cells through PI3K/AKT signaling pathway by targeting PAX6

BackgroundRetinoblastoma (RB) is the most common primary intraocular malignancy in children. Accumulating evidences have clarified that microRNAs (miRNAs) modulated signaling molecules by acting as oncogenes or tumor-suppressor genes in RB. Thus, in our study, we aimed to investigate the function of miR-129-5p in RB cells through PI3K/AKT signaling pathway by targeting PAX6. Two RB cell lines, Y79 and WERI-Rb-1, were selected in our study, followed by transfection of miR-129-5p inhibitor or si-PAX6 to explore the regulatory role of miR-129-5p in RB cell proliferation, invasion and migration.Material and methodsDual-luciferase assay was used for the detection of targeting relationship between miR-129-5p and PAX6. Besides, western blot analysis was applied to detect expression of cell cycle-related factors (CDK2 and Cyclin E) and PI3K/AKT signaling pathway-related factors (p-AKT and AKT). Nude mice tumorigenesis experiment was used to evaluate the effect of miR-129a-5p on RB growth in vivo.ResultsmiR-129-5p was down-regulated in RB cell lines. miR-129-5p directly targeted the 3′-untranslated region of PAX6. Artificial down-regulation of miR-129-5p promoted cell proliferation, migration and invasion in RB cell lines Y79 and WERI-Rb-1, and promoted RB growth in vivo via PI3K/AKT signaling pathway, which could be reversed by transfection with silencing PAX6.ConclusionThis study provides evidences that RB progression was suppressed by overexpressed miR-129-5p via direct targeting of PAX6 through PI3K/AKT signaling pathway, which may provide a molecular basis for better treatment for RB.     

PI3K/AKT signaling pathway plays a role in enhancement of eNOS activity by recombinant human angiotensin converting enzyme 2 in human umbilical vein endothelial cells

The aim of this study was to investigate the effect of PI3K/AKT signaling pathway in the activity of recombinant human angiotensin converting enzyme 2 (rhACE2) promoted the activity of endothelial nitric oxide synthase (eNOS). The human umbilical vein endothelial cells (HUVEC) were cultured in vitro. Then treated with Ang II (1×10^-6 mol/L) for 24 h. The rhACE2 (100 μmol/L) was added and incubated for 5, 10, 15, 30, 60 min respectively which was based on Ang II intervention. The effect of rhACE2 on phosphorylation eNOS level was also observed in the presence of {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002 (10 μmol/L) (PI3K/AKT inhibitors). Griess reagent method was applied to measure NO contents in cell culture supernatant, RT-PCR to detect the expression of eNOSmRNA in HUVEC, and Western blot to detect the expression of eNOS and phosphorylated eNOS. In Ang II intervention group, NO contents were significantly lower than control group (P < 0.05). Through rhACE2 treatment, the NO contents in cell culture medium and the expression level of phosphorylated eNOS were significantly higher than in Ang II intervention group (P < 0.05), but eNOSmRNA and non-phosphorylated eNOS protein expression level showed no significant difference (P > 0.05). After HUVEC was intervened by PI3K/AKT pathway inhibitor {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002, the expression level of phosphorylated eNOS was significantly lower than that in the rhACE2 30 min treatment group (P < 0.05). rhACE2 may reduce the activity of Ang II inhibited endothelial cell eNOS, which can be blocked by PI3K/AKT pathway inhibitor {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002, suggesting PI3K/AKT signaling pathway plays an important role in rhACE2’s promotion of the activity of endothelial cell eNOS.     

Prostaglandin transporter,SLCO2A1, mediates the invasion and apoptosis of lung cancer cells via PI3K/AKT/mTOR pathway

Treatment of lung cancer involves regulation of various key factors in many signaling pathways. The prostaglandin transporter, solute carrier organic anion transporter family member 2A1 (SLCO2A1), is a promising regulatory factor of cancer cells. By analyzing the invasion and apoptosis status of lung cancer cells, and detecting the expression changes of key factors in PI3K/AKT/mTOR pathway after overexpression and knockdown of SLCO2A1 in vitro, this study intended to investigate the function of SLCO2A1 in mediating lung cancer cells. Results showed overexpression of SLCO2A1 could induce the invasion of lung cancer cells, and its knockdown inhibited the invasion and induced the apoptosis of cells. mTOR, AKT and S6 in PI3K/AKT/mTOR pathway were not affected by SLCO2A1. But the expression levels of p-mTOR, p-AKT and p-S6 were up-regulated or down-regulated with the overexpression or knockdown of SLCO2A1. Thus SLCO2A1 was inferred to mediate the invasion and apoptosis of lung cancer cells via PI3K/AKT/mTOR pathway. These results implied SLCO2A1 could be a regulatory factor of the invasion and apoptosis of lung cancer cells and serve as a promising target for lung cancer therapy.     

参慈胶囊联合顺铂通过PI3K/AKT/mTOR信号通路逆转人肺腺癌顺铂耐药的机制研究

目的:探讨参慈胶囊联合顺铂是否通过PI3K/AKT/mTOR信号通路逆转接种人肺腺癌A549/DDP细胞的裸鼠体内的顺铂耐药。方法:建立裸鼠人肺腺癌移植瘤模型,随机分为对照组、参慈胶囊组、顺铂组和参慈胶囊+顺铂组。对照组予生理盐水,其余各组荷瘤裸鼠均用药21 d,断颈处死,取肿瘤组织,采用流式细胞术检测细胞周期与细胞凋亡;采用FQ-PCR技术检测A549/DDP肺癌组织PTEN、P-糖蛋白、PI3K、AKT和mTOR的mRNA表达情况。结果:参慈胶囊组、顺铂组和参慈胶囊+顺铂组与对照组比较,对人肺腺癌A549/DDP细胞的增殖均有抑制作用,其中参慈胶囊+顺铂组较其它治疗组能够进一步将人肺腺癌A549/DDP细胞阻滞于G_2/M期,促进细胞凋亡,增加PTEN的表达,抑制P-糖蛋白、PI3K、AKT和mTOR的表达。结论:参慈胶囊可能通过阻断PI3K/AKT/mTOR信号通路,促进PTEN的表达,或者抑制P-糖蛋白介导的耐药途径,增强裸鼠体内人肺腺癌A549/DDP耐药细胞对顺铂的敏感性。     

芝麻素改善自发性高血压大鼠肾损伤的作用及与PI3K/AKT/mTOR信号通路的关系

 目的: 观察芝麻素对自发性高血压大鼠(spontaneously hypertensive rats,SHR)肾脏损伤的作用及与PI3K/AKT/mTOR信号通路之间的关系。方法: 雄性SHR随机分成模型组、芝麻素低剂量(80 mg/kg)、高剂量(160 mg/kg)组及卡托普利(30 mg/kg)组。同时选取同周龄WKY大鼠作为正常对照组。每日灌胃1次,模型组、正常对照组给予0.5%羧甲基纤维素钠(CMC-Na),给药组给予CMC-Na溶解的上述剂量药物,给药前及给药后每隔2周测量1次血压。12周后,检测血尿素氮(BUN)、肌酐(SCr)及尿微量白蛋白(U-mAlb)含量;测定肾脏丙二醛(MDA)和超氧化物歧化酶(SOD)水平;HE、Masson染色观察肾组织病理学变化;TUNEL法检测肾组织细胞凋亡率;Western blot法检测肾脏p-AKT、p-mTOR、4EBP1、S6K1、Bcl-2和Bax的蛋白水平。结果: 芝麻素能降低SHR舒张压,明显改善肾组织的病理学变化,降低肾脏BUN、SCr、U-mAlb、MDA含量及细胞凋亡率,提高SOD活性,显著减少p-AKT、p-mTOR、4EBP1、S6K1和Bax的蛋白水平,增加Bcl-2的蛋白表达。结论: 芝麻素减轻SHR大鼠肾脏损伤的作用机制可能与降低血压、对抗氧化应激、抑制细胞凋亡、阻滞过度活化的PI3K/AKT/mTOR信号通路有关。     

Lycopene alleviates food allergy by modulating the PI3K/AKT pathway in peanut-sensitized BALB/c mice

Food allergies, which lead to life-threatening acute symptoms, are considered an important public health problem. Therefore, it is essential to develop efficient preventive and treatment measures. We developed a crude peanut protein extract (PPE)–induced allergy mouse model to investigate the effects of lycopene on peanut allergy. Mice were divided into four groups: 5 mg/kg lycopene, 20 mg/kg lycopene, no treatment, and control groups. Serum inflammatory factors were detected using enzyme-linked immunosorbent assay. In addition, pathology and immunohistochemistry analyses were used to examine the small intestine of mice. We found that lycopene decreased PPE-specific immunoglobulin E (IgE) and IL-13 levels in the serum, relieved small intestine inflammation, attenuated the production of histamine and mouse mast cell protease-1, and downregulated PI3K and AKT1 expression in the small intestine tissues of mice allergic to peanuts. Our results suggest that lycopene can ameliorate allergy by attenuating the PI3K/AKT pathway and the anaphylactic reactions mediated by PPE-specific IgE.     

Role of TM4SF1 in regulating breast cancer cell migration and apoptosis through PI3K/AKT/mTOR pathway

Purpose: The purpose of this study was to investigate the effect of transmembrane-4-l-six-family-1 (TM4SF1) on breast cancer cell line MDA-MB-231 invasion and apoptosis and its mechanism through PI3K/AKT/mTOR pathway. Methods: siRNA-TM4SF1 and pcDNA-TM4SF1 plasma were constructed and then transfected into MDA-MB-231 cells respectively. Real time (RT)-PCR was used to measure the mRNA expression of TM4SF1 in each group. Also, matrigel method and Annexin V-FITC were used to detect the effect of TM4SF1 expression on MDA-MB-231 cell migration and apoptosis respectively. Besides, western blotting analyze was used to assay the effects of TM4SF1 expression on PI3K/AKT/mTOR pathway associated proteins expressions. Results: The results showed that after being transfected with siRNA-TM4SF1, TM4SF1 expression was significantly declined, while it was significantly increased after cells were transfected with pcDNA-TM4SF1 (P<0.05). Compared with the controls, TM4SF1 overexpression significantly contributed MDA-MB-231 cell migration but decreased apoptotic cells (P<0.05), which were opposite to the results when TM4SF1 was sliced in cells. Moreover, TM4SF1 slicing significantly decreased the expressions of phosphorylated (p)-AKT, p-mTOR, and p-P70 (P<0.05). Conclusion: Our study suggested that TM4SF1 may be a therapeutic target for breast cancer treatment and may loan insight into the mechanisms behind the development and metastasis of advanced breast cancer.     

BTG2 inhibits the proliferation and metastasis of osteosarcoma cells by suppressing the PI3K/AKT pathway

B cell translocation gene 2 (BTG2) has been reported to be a potential tumor suppressor in many types of tumors. However, the roles and molecular mechanisms of BTG2 in osteosarcoma progression are still unknown. In this study, we investigated the role of BTG2 in proliferation and metastasis of osteosarcoma and the underlying mechanism. BTG2 expression levels were measured in fresh osteosarcoma tissues and cell lines. The effects of BTG2 on cell proliferation, migration and invasion were explored by MTT, transwell assays, western blot, and in vivo tumorigenesis in nude mice. We found that BTG2 was down-regulated in human osteosarcoma tissues and cell lines. Overexpression of BTG2 inhibited the proliferation and migration/invasion of human osteosarcoma cells in vitro, it also markedly inhibited xenograft tumor growth in vivo. Furthermore, BTG2 significantly decreased the expression of phosphorylated PI3K and AKT in osteosarcoma cells. Taken together, our data indicate that BTG2 might suppress the tumor growth and metastasis via PI3K/AKT signaling pathway, implying that BTG2 may serve as a potential molecular target for the treatment of osteosarcoma.     

Immunohistochemical and molecular analysis of PI3K/AKT/mTOR pathway in esophageal carcinoma

Among the numerous signaling pathways involved in tumorigenesis, PI3K‐AKT‐mTOR is a key one that regulates diverse cellular functions. However, its prognostic value in esophageal carcinoma remains unclear. In our study, we examined the immunohistochemical expression of phosphorylated (p‐) AKT, mTOR, p70S6K and 4E‐BP1 along with the mutational status of PIK3CA and AKT1 genes by High Resolution Melting Analysis and Pyrosequencing in 44 esophageal carcinomas. The results were correlated with the clinicopathological characteristics of the patients in an effort to define their possible prognostic significance. Total p‐mTOR cytoplasmic expression, assessed in 10 random areas, was positively correlated with tumor stage (Kruskal–Wallis ANOVA, I/II vs III/IV, p = 0.0500). Μoreover, maximum p‐mTOR cytoplasmic immunoexpression, estimated in hot spot areas, was positively associated with tumor grade (Mann–Whitney U test, I/II vs III, p = 0.0565). Interestingly, p‐4E‐BP1 immunoreactivity was negatively correlated with tumor histological grade (Mann–Whitney U test, I/II vs III, p = 0.0427). No mutation was observed in exons 9 and 20 of PIK3CA gene and in exon 4 of AKT1 gene. In conclusion, our findings depict the presence of activated PI3K/AKT/mTOR pathway in esophageal cancer bringing forward p‐mTOR and p‐4E‐BP1 for their potential role in esophageal carcinogenesis. Additional studies are warranted to validate our findings.     

PI3K/AKT通路介导H_2O_2预处理减轻PC12细胞氧化损伤

目的探讨PI3K/AKT信号通路是否参与H2O2预处理诱导的适应性细胞保护作用。方法体外培养PC12细胞,建立H2O2预处理对抗高浓度H2O2诱导细胞损伤的实验模型。应用甲氮甲唑蓝(MTT)法测定细胞的存活率,比色法测定乳酸脱氢酶(LDH)的活性,碘化丙啶(PI)染色流式细胞术检测细胞凋亡率,免疫印迹法(Westernblot)测定AKT的表达。结果 100μmol H2O2预处理PC12细胞90 min可显著地抑制300μmol H2O2引起的损伤,使细胞存活率从50.2%±4.6%升高至83.8%±3.5%,LDH活性由103%±10.2%下降至68.5%±5.3%,细胞凋亡率由65.5%±4.1%下降至37.1%±2.3%(P<0.01)。100μmol H2O2预处理诱导p-AKT的表达,PI3K抑制剂ly294002阻断了H2O2预处理引起的p-AKT表达。同时ly294002拮抗了H2O2预处理诱导的抗细胞损伤和凋亡作用。结论 H2O2预处理通过PI3K途径引起AKT的活化,PI3K/AKT通路的活化介导了H2O2预处理诱导的适应性细胞保护作用。     

1-磷酸鞘氨醇受体2介导PI3K/AKT/eNOS通路抑制甲型流感病毒诱导的病毒性肺炎

目的:探讨1-磷酸鞘氨醇受体2(S1PR2)对甲型流感病毒诱导的病毒性肺炎的作用及机制。方法:采用甲型流感病毒鼠肺适应株FM1滴鼻感染野生C57BL/6小鼠和S1pr2~(-/-)小鼠,建立甲型流感病毒性肺炎动物模型。病毒感染4和6 d时观察比较对照组(模型组的野生小鼠)、JTE-013(S1PR2高效拮抗剂)处理的小鼠及S1pr2~(-/-)小鼠肺组织的病理改变,检测支气管肺泡灌洗液(BALF)中的蛋白浓度、细胞总数及细胞因子[白细胞介素(IL)-1β、IL-6和肿瘤坏死因子α(TNF-α)]的表达,Western blot法检测小鼠肺组织的AKT和e NOS的磷酸化水平。结果:与模型对照组的野生鼠比较,JTE处理组和S1pr2~(-/-)组甲型流感病毒性肺炎更加严重;BALF中的蛋白浓度,总细胞数及炎性细胞因子表达显著增加;且PI3K下游靶点AKT和e NOS磷酸化显著增高(P0.01)。结论:S1PR2通过介导PI3K/AKT/e NOS信号转导通路,调节NO生成,抑制血管通透性和炎性细胞因子释放,从而减轻甲型流感病毒诱导的病毒性肺炎。