Alisol B acetate induces apoptosis of SGC7901 cells via mitochondrial and phosphatidylinositol 3-kinases/Akt signaling pathways

AIM： To examine the effect of alisol B acetate on the growth of human gastric cancer cell line SGC7901 and its possible mechanism of action.METHODS： The cytotoxic effect of alisol B acetate on SGC7901 cells was measured by 3-（4,5-dimethylthiazol- 2-yl）-2,5-diphenyltetrazolium bromide （MI-I-） assay. Phase-contrast and electron microscopy were used to observe the morphological changes. Cell cycle and mitochondrial transmembrane potential （A^Pm） were determined by flow cytometry. Western blotting was used to detect the expression of apoptosis-regulated gene Bcl-2, Bax, Apaf-1, caspase-3, caspase-9, Akt, P-Akt and phosphatidylinositol 3-kinases （PI3K）.RESULTS： Alisol B acetate inhibited the proliferation of SGC7901 cell line in a time- and dose-dependent manner. PI staining showed that alisol B acetate can change the cell cycle distribution of SGC7901, increase the proportion of cells in G0-G1 phase and decrease the proportion of S phase cells and G2-M phase cells. Alisol B acetate at a concentration of 30 pmol/L induced apoptosis after 24, 48 and 72 h incubation, with occurrence rates of apoptotic cells of 4.36%, 14.42% and 21.16%, respectively. Phase-contrast and electron microscopy revealed that the nuclear fragmentation and chromosomal condensed, cells shrank and attachment loss appeared in the SGC7901 treated with alisol B acetate. Apoptosis of SGC7901 cells was associated with cell cycle arrest, caspase-3 and caspase-9 activation, loss of mitochondrial membrane potential and up-regulation of the ratio of Bax/Bcl-2 and inhibition of the PI3K/Akt.CONCLUSION： Alisol B acetate exhibits an antiproliferative effect in SGC7901 cells by inducing apoptosis. Apoptosis of SGC7901 cells involves mitochondria-caspase and PI3K/Akt dependent pathways.

Herbal cake-partitioned moxibustion inhibits colonic autophagy in Crohn’s disease via signaling involving distinct classes of phosphatidylinositol 3-kinases

BACKGROUND Autophagy is an evolutionarily conserved biological process in eukaryotic cells that involves lysosomal-mediated degradation and recycling of related cellular components.Recent studies have shown that autophagy plays an important role in the pathogenesis of Crohn’s disease(CD).Herbal cake-partitioned moxibustion(HM)has been historically practiced to treat CD.However,the mechanism by which HM regulates colonic autophagy in CD remains unclear.AIM To observe whether HM can alleviate CD by regulating colonic autophagy and to elucidate the underlying mechanism.METHODS Rats were randomly divided into a normal control(NC)group,a CD group,an HM group,an insulin+CD(I+CD)group,an insulin+HM(I+HM)group,a rapamycin+CD(RA+CD)group,and a rapamycin+HM(RA+HM)group.2,4,6-trinitrobenzenesulfonic acid was administered to establish a CD model.The morphology of the colonic mucosa was observed by hematoxylin-eosin staining,and the formation of autophagosomes was observed by electron microscopy.The expression of autophagy marker microtubule-associated protein 1 light chain 3 beta(LC3B)was observed by immunofluorescence staining.Insulin and rapamycin were used to inhibit and activate colonic autophagy,respectively.The mRNA expression levels of phosphatidylinositol 3-kinase class I(PI3KC1),Akt1,LC3B,sequestosome 1(p62),and mammalian target of rapamycin(mTOR)were evaluated by RT-qPCR.The protein expression levels of interleukin 18(IL-18),tumor necrosis factor-α(TNF-α),nuclear factorκB/p65(NF-κB p65),LC3B,p62,coiled-coil myosin-like BCL2-interacting protein(Beclin-1),p-mTOR,PI3KC1,class III phosphatidylinositol 3-kinase(PI3KC3/Vps34),and p-Akt were evaluated by Western blot analysis.RESULTS Compared with the NC group,the CD group showed severe damage to colon tissues and higher expression levels of IL-18 and NF-κB p65 in colon tissues(P<0.01 for both).Compared with the CD group,the HM group showed significantly lower levels of these proteins(PIL-18<0.01 and Pp65<0.05).There were no significant differences in the expression of TNF-αprotein in colon tissue among the rat groups.Typical autophagic vesicles were found in both the CD and HM groups.The expression of the autophagy proteins LC3B and Beclin-1 was upregulated(P<0.01 for both)in the colon tissues of rats in the CD group compared with the NC group,while the protein expression of p62 and p-mTOR was downregulated(P<0.01 for both).However,these expression trends were significantly reversed in the HM group compared with the CD group(PLC3B<0.01,PBeclin-1<0.05,Pp62<0.05,and Pm-TOR<0.05).Compared with those in the RA+CD group,the mRNA expression levels of PI3KC1,Akt1,mTOR,and p62 in the RA+HM group were significantly higher(PPI3KC1<0.01 and PAkt1,mTOR,and p62<0.05),while those of LC3B were significantly lower(P<0.05).Compared with the RA+CD group,the RA+HM group exhibited significantly higher PI3KC1,p-Akt1,and pmTOR protein levels(PPI3KC1<0.01,Pp-Akt1<0.05,and Pp-mTOR<0.01),a higher p62 protein level(P=0.057),and significantly lower LC3B and Vps34 protein levels(P<0.01 for both)in colon tissue.CONCLUSION HM can activate PI3KC1/Akt1/mTOR signaling while inhibiting the PI3KC3(Vps34)-Beclin-1 protein complex in the colon tissues of CD rats,thereby inhibiting overactivated autophagy and thus exerting a therapeutic effect.

Tumor-related factor complement Clq/TNF-related protein 6 affects the development of digestive system tumors through the phosphatidylinositol 3-kinase pathway

In this editorial,we review the work of Razali et al published in World J Gas-troenterology,with a particular focus on the effect of rs10889677 variation in the phosphatidylinositol 3-kinase(PI3K)pathway and buparlisib on colitis-associated cancer.The role of PI3K in promoting cancer progression has been widely recognized,as it is involved in regulating the survival,differentiation,and prolif-eration of cancer cells.The complement Clq/TNF-related protein 6(CTRP6)is a newer tumor-associated factor.Recent studies have revealed the pro-tumor effect of CTRP6 in gastric cancer,hepatocellular carcinoma,colorectal cancer,and other gastrointestinal tumors through the PI3K pathway.This article attempts to reveal the mechanism through which the CTRP6 affects the development of digestive system tumors through the PI3K pathway by summarizing recent research.

Roles of phosphatidylinositol-3-kinases signaling pathway in inflammation-related cancer:Impact of rs10889677 variant and buparlisib in colitis-associated cancer

BACKGROUND Phosphatidylinositol-3-kinases(PI3K)is a well-known route in inflammationrelated cancer.Recent discovery on PI3K-related genes revealed a potential variant that links ulcerative colitis(UC)and colorectal cancer(CRC)with colitisassociated cancer(CAC).PI3K/AKT pathway has been recommended as a potential additional therapeutic option for CRC due to its substantial role in modifying cellular processes.Buparlisib is a pan-class I PI3K inhibitor previously shown to reduce tumor growth.AIM To investigate the regulation of rs10889677 and the role of buparlisib in the PI3K signaling pathway in CAC pathogenesis.METHODS Genomic DNA from 32 colonic samples,including CAC(n=7),UC(n=10)and CRC(n=15),was sequenced for the rs10889677 mutation.The mutant and wildtype fragments were amplified and cloned in the pmirGLO vector.The luciferase activity of cloned vectors was assessed after transfection into the HT29 cell line.CAC mice were induced by a mixture of a single azoxymethane injection and three cycles of dextran sulphate sodium,then buparlisib was administered after 14 d.The excised colon was subjected to immunohistochemistry for Ki67 and Cleaved-caspase-3 markers and quantitative real-time polymerase chain reaction analysis for Pdk1 and Sgk2.RESULTS Luciferase activity decreased by 2.07-fold in the rs10889677 mutant,confirming the hypothesis that the variant disrupted miRNA binding sites,which led to an increase in IL23R expression and the activation of the PI3K signaling pathway.Furthermore,CAC-induced mice had a significantly higher disease activity index(P<0.05).Buparlisib treatment significantly decreased mean weight loss in CAC-induced mice(P<0.05),reduced the percentage of proliferating cells by 5%,and increased the number of apoptotic cells.The treatment also caused a downward trend of Pdk1 expression and significantly decreased Sgk2 expression.CONCLUSION Our findings suggested that the rs10889677 variant as a critical initiator of the PI3K signaling pathway,and buparlisib had the ability to prevent PI3K-non-AKT activation in the pathophysiology of CAC.

Osteopontin promotes gastric cancer progression via phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway

BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors.Osteopontin(OPN)is thought to be closely related to the occurrence,metastasis and prognosis of many types of tumors.AIM To investigate the effects of OPN on the proliferation,invasion and migration of GC cells and its possible mechanism.METHODS The mRNA and protein expression of OPN in the GC cells were analyzed by realtime quantitative-reverse transcription polymerase chain reaction and western blotting,and observe the effect of varying degree expression OPN on the proliferation and other behaviors of GC.Next,the effects of OPN knockdown on GC cells migration and invasion were examined.The short hairpin RNA(shRNA)and negative control shRNA targeting OPN-shRNA were transfected into the cells according to the manufacturer’s instructions.Non transfected cells were classified as control in the identical transfecting process.24 h after RNA transfection cell proliferation activity was detected by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay,and cell invasiveness and migration were detected by Trans well assay.Meanwhile,the expression of protein kinase B(AKT),matrix metalloproteinase 2(MMP-2)and vascular endothelial growth factor(VEGF)in the human GC cell lines was detected by reverse transcription polymerase chain reaction and western blotting.RESULTS The results of this study revealed that OPN mRNA and protein expression levels were highly expressed in SGC-7901 cells.OPN knockdown by specific shRNA noticeably reduced the capabilities of proliferation,invasion and migration of SGC-7901 cells.Moreover,in the experiments of investigating the underlying mechanism,results showed that OPN knockdown could down-regulated the expression of MMP-2 and VEGF,it also decreased the phosphorylation of AKT.Meanwhile,the protein expression levels of MMP-2,VEGF and phosphorylated AKT was noticeable lower than that in control group in the GC cells after they were added to phosphatidylinositol-3-kinase(PI3K)inhibitor(LY294002).CONCLUSION These results suggested that OPN though PI3K/AKT/mammalian target of rapamycin signal pathway to upregulate MMP-2 and VEGF expression,which contribute SGC-7901 cells to proliferation,invasion and migration.Thus,our results demonstrate that OPN may serve as a novel prognostic biomarkers as well as a potential therapeutic targets for GC.

Glycine-extended gastrin activates two independent tyrosine-kinases in upstream of p85/p110 phosphatidylinositol 3-kinase in human colonic tumour cells

AIM： To investigate whether Src, JAK2 and phosphatidylinositol 3-kinase （PI3K） pathways are involved in the proliferation of human colonic tumour cells induced by glycine-extended gastrin （G-gly）, the precursor of the mature amidated gastrin and to elucidate the molecular interaction between these three kinases in response to this peptide. METHODS： Using the human colonic tumour cell line HCT116 as a model, we first measured the activation of PI3K, p60-Src and JAK2 in response to G-gly by in vitro kinase assays. Then we investigated the involvement of these kinases in G-gly-induced cell proliferation by MTT test. RESULTS： G-gly stimulation induced p60-Src, JAK2 and PI3K activation in HCT116. The different pathways were involved in proliferation of human colon cancer cells induced by G-gly. Furthermore, we found that both Src and JAK2 were necessary to PI3K regulation by this peptide. However, we did not find any cross-talk between the two tyrosine kinases. CONCLUSION： Our results suggest that the p60-Src/ PI3K and JAK2/PI3K pathways act independently to mediate G-gly proliferative effect on human colonic tumour cells.

Efficacy of self-made Gengnian decoction on phosphatidylinositol 3-kinases/protein kinase B/mammalian target of rapamycin signaling pathway in perimenopausal rats

OBJECTIVE:To investigate the efficacy of self-made Gengnian decoction on expressions of phosphatidylinositol 3-kinase(PI3 K),protein kinase B(Akt)and mammalian target of rapamycin(m TOR)in ovarian tissues of perimenopausal rats.They were identified with symptom pattern of kidney-Yang deficiency in terms of Traditional Chinese Medicine.METHODS:Female Sprague-Dawley rats aged10-12 months were selected.Estrous cycle was observed by vaginal smears of keratinocytes to screen the perimenopausal model rats.The chosen rats were randomly divided into five groups,including perimenopausal model of kidney-Yang deficiency group(24 rats),self-made Gengnian decoction of high-dose group(24 rats),self-made Gengnian decoction of middle-dose group(24 rats),self-made Gengnian decoction of low dose group(24 rats)and tibolone control group(24 rats).In addition,rats aged 4-6 months were selected as young control group.The perimenopausal model rats of kidney-Yang deficiency were prepared by alternative intramuscular injection of hydrocortisone 5 mg·kg^-1·d^-1The successfully prepared models in self-made Gengnian decoction of high-dose,middle-dose and low-dose groups and tibolone control group were given self-made Gengnian decoction 26.4,13.2 and 6.6 mg·kg^-1·d^-1,and tibolone tablets solvent 0.22 mg·kg^-1·d^-1,respectively,through intragastric administration.Models group and young control group were given the same dose of normal saline,1 time a day for 15 consecutive days.24 h after the last administration,blood and ovarian tissues were collected after anesthesia with 20%ethyl carbamate.The follicles of different levels in ovarian tissue were observed and counted by histopathological hematoxylin-eosin staining.Enzyme linked immunosorbent assay was applied to test insulin-like growth factor-1(IGF-1)level in the serum of experimental rats.The expression levels of PI3 K,phosphorylated-Akt(p-Akt)and phosphorylated-m TOR(p-m TOR)m RNA in ovarian tissue were detected by quantitative real-time polymerase chain reaction.RESULTS:The total follicle counts of perimenopausal model rats with kidney-Yang deficiency were significantly reduced,and the number of follicles(mainly increased in preantral follicles and antral follicles)in perimenopausal model rats with kidney-Yang deficiency was significantly increased after intervention of high and middle doses of Gengnian decoction and tibolone(P<0.05).Compared with normal rats in young control group,the levels of IGF-1 in serum of perimenopausal rats with kidney-Yang deficiency were significantly decreased(P<0.01),and those intervened by high dose of Gengnian decoction and tibolone were significantly up-regulated.The relative expression levels of PI3 K,p-Akt,p-m TOR m RNA in ovarian tissues of perimenopausal rats with kidney-Yang deficiency were significantly lower than those of young rats(P<0.01),and those intervened by high dose of Gengnian decoction and tibolone were significantly up-regulated(P<0.05).CONCLUSION:Self-made Gengnian decoction can increase the levels of IGF-1,PI3 K,Akt and m TOR m RNA expression in serum.

黄芪阳和汤调控PI3K/AKT/NF-κB信号通路促进糖尿病足溃疡大鼠创面愈合

目的基于磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/核因子-κB(NF-κB)信号通路探究黄芪阳和汤对糖尿病足溃疡(DFU)大鼠创面愈合的影响。方法构建DFU大鼠模型,将建模成功的48只大鼠随机分为模型组,黄芪阳和汤低(8.5 g/kg)、高(17 g/kg)剂量组,黄芪阳和汤高剂量(17 g/kg)+LY294002(PI3K/AKT通路抑制剂,0.3 mg/kg)组;每组12只;另取12只大鼠为对照组。各组大鼠给予对应药物干预,连续4周。第14、28天给药后,观察大鼠一般状态及创面变化,计算创面愈合率,检测大鼠空腹血糖(FBG)水平和大鼠创面周围组织经皮氧分压(TcpO2);酶联免疫吸附试验检测大鼠血清血管内皮生长因子(VEGF)、缺氧诱导因子-1α(HIF-1α)、C反应蛋白(CRP)、白细胞介素(IL)-6水平;苏木素-伊红染色观察大鼠创面组织病理学变化;免疫组织化学染色测定大鼠创面组织微血管密度;蛋白免疫印迹法检测大鼠创面组织中PI3K、磷酸化PI3K(p-PI3K)、AKT、磷酸化AKT(p-AKT)、NF-κB p65、磷酸化NF-κB p65(p-NF-κB p65)、NF-κB抑制蛋白α(IκB-α)蛋白表达。结果对照组大鼠毛色光滑,饮食、饮水、排泄均正常,较活跃,创面愈合快,创面组织炎症反应较轻,新生血管较多,肉芽组织中成纤维细胞及胶原基质丰富;模型组大鼠毛色暗淡无光泽,活动减少,且出现多饮、多食、多尿症状,创面颜色较深,且周围组织出现水肿、溃疡,创面组织可见大量炎性细胞浸润,伴组织坏死、渗出,新生血管及成纤维细胞较少,创面愈合率、创面周围组织TcpO2、血清VEGF、HIF-1α、创面组织微血管密度、p-PI3K、p-AKT、IκB-α蛋白表达水平降低,FBG、血清CRP、IL-6、创面组织p-NF-κB p65蛋白表达升高(P<0.05);与模型组相比,黄芪阳和汤低、高剂量组大鼠状态逐渐改善,创面组织病变程度依次减轻,创面愈合率、创面周围组织TcpO2、血清VEGF、HIF-1α、创面组织微血管密度、p-PI3K、p-AKT、IκB-α蛋白表达水平依次升高,FBG、血清CRP、IL-6、创面组织p-NF-κB p65蛋白表达依次降低(P<0.05);LY294002能部分逆转高剂量黄芪阳和汤对DFU大鼠的治疗作用(P<0.05)。结论黄芪阳和汤能调控PI3K/AKT/NF-κB信号通路,抑制DFU大鼠炎症反应,促进血管新生,从而促进创面愈合。

栀子苷调节PI3K/AKT/mTOR信号通路在动脉粥样硬化形成过程中对Th17/Treg功能的影响

目的:观察栀子苷对载脂蛋白E缺乏(ApoE^(-/-))小鼠Th17/调节性T(Treg)细胞失衡的影响及其作用机制。方法:将50只纯合子ApoE^(-/-)雌性小鼠随机分为对照组、模型组和栀子苷低剂量组、栀子苷中剂量组、栀子苷高剂量组。对照组小鼠喂养普通饲料,模型组和栀子苷组小鼠喂养高脂饲料。从第8周开始,栀子苷各剂量组每日灌胃栀子苷(25、50、100 mg/kg),连续8周。试验结束时,采用油红O染色评估主动脉及其根部动脉粥样硬化(AS)病变面积比。采用定量逆转录聚合酶链式反应(RT-PCR)分析主动脉组织肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-17A和IL-10 mRNA表达;采用流式细胞仪分析脾脏中Th17和Treg细胞百分比;蛋白免疫印迹法(Western Blot)检测主动脉组织磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路相关蛋白表达。结果:油红O染色病变显示,栀子苷中剂量组、栀子苷高剂量组病变百分比低于模型组(P<0.05)。与对照组比较,模型组主动脉TNF-α、IL-6和IL-17A mRNA表达水平升高(P<0.05);栀子苷各剂量组主动脉TNF-α、IL-6和IL-17A mRNA表达水平降低(P<0.05)。与对照组比较,模型组主动脉抗炎细胞因子IL-10 mRNA表达水平降低(P<0.05);栀子苷各剂量组主动脉抗炎细胞因子IL-10 mRNA表达水平升高(P<0.05)。与对照组比较,模型组小鼠脾脏中Th17细胞百分比升高,Treg细胞百分比降低(P<0.05)。栀子苷处理恢复了AS小鼠Th17和Treg细胞的平衡。栀子苷抑制PI3K的表达及AKT和mTOR的磷酸化,MHY1485(mTOR活化剂)减弱了栀子苷对T细胞分化的影响。结论:栀子苷抗AS作用机制可能与抑制PI3K/AKT/mTOR信号引起的Treg细胞增多和Th17细胞减少有关。

葛根芩连汤通过IRS-1/PI3K/AKT通路对胃肠湿热型2型糖尿病大鼠糖脂代谢的影响

目的探究葛根芩连汤通过胰岛素受体底物-1(IRS-1)/磷脂酰肌醇3激酶(PI3K)/蛋白激酶B(AKT)通路对胃肠湿热型2型糖尿病大鼠糖脂代谢的影响。方法将40只SD大鼠随机分为正常组(2 mL生理盐水灌胃)、造模组(2 mL生理盐水灌胃)、二甲双胍组(4.17 mg/100 g二甲双胍灌胃)和葛根芩连汤组(1 g/100 g葛根芩连汤灌胃),每组10只。采用高脂高糖饲料加腹腔注射链脲佐菌素(STZ)构建2型糖尿病大鼠模型,随后喂食油脂、42°白酒及蜂蜜水构建胃肠湿热型2型糖尿病大鼠模型。测量各组大鼠不同时间节点体质量,血糖仪测定空腹血糖(FBG);ELISA检测空腹胰岛素(FINS)、三酰甘油(TG)、总胆固醇(TC)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平变化、计算胰岛素抵抗指数(HOMA-IR);HE染色检测肝组织病理学变化;检测肝组织过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)及丙二醛(MDA)含量变化。Western blot检测肝组织IRS-1、PI3K、p-PI3K、AKT及p-AKT蛋白变化。结果与正常组比较,造模组大鼠体质量、FBG、FINS及HOMA-IR、GSH-Px、CAT、SOD、IRS-1、p-PI3K/PI3K及p-AKT/AKT水平均明显下降(P<0.05)、TG、TC、IL-6、TNF-α及MDA含量均显著升高(P<0.05),可见局灶性肝实质损失。与造模组比较,二甲双胍组及葛根芩连汤组大鼠体质量、FBG、FINS及HOMA-IR、GSH-Px、CAT、SOD、IRS-1、p-PI3K/PI3K及p-AKT/AKT水平均明显升高(P<0.05)、TG、TC、IL-6、TNF-α及MDA含量均显著降低(P<0.05),显示正常的肝实质。结论葛根芩连汤可明显改善胃肠湿热型2型糖尿病糖脂紊乱,可能是通过IRS-1/PI3K/AKT通路发挥作用。

PI3K信号过度活化引发免疫病理机制研究进展

目前少数研究发现磷脂酰肌醇3-激酶(PI3K)基因PIK3CD(编码p110δ)发生功能获得性(GOF)变异后,可导致活化的PI3Kδ综合征(APDS)。该突变可通过诱导T细胞减少/衰老/耗竭、B细胞发育受阻、NK细胞毒性降低等多种免疫系统内部缺陷机制导致机体内免疫缺陷、免疫失调甚至肿瘤发生。本文主要对PI3Kδ GOF诱导APDS发生的相关临床疾病特点及免疫缺陷分子机制展开综述,重点阐述该突变导致淋巴细胞发育、分化及功能缺陷的分子机制。

基于转录组学分析PI3K/AKT通路对冷却滩羊肉贮藏期间肌肉代谢稳态的影响

为揭示磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinase,PI3K)/蛋白激酶B(protein kinase B,AKT)信号通路在冷却滩羊肉贮藏期间代谢调控中的作用,采用高通量测序技术研究冷却滩羊肉经PI3K抑制剂LY294002注射处理后分别在贮藏期为0、4、8 d时转录组的变化。在对照组和LY294002处理组之间,0、4、8 d时被鉴定为显著差异表达基因(differentially expressed genes,DEGs)数分别为474、96、13。功能富集分析表明,DEGs主要与代谢稳态有关,如氨基酸的生物合成、糖酵解/糖异生、甘油脂类代谢过程。此外,组织切片分析显示,与对照组相比,LY294002组肌纤维间距增加,肌纤维直径显著减小,表明肌肉发生萎缩。结果表明,PI3K/AKT信号通路在维持滩羊肉贮藏过程中代谢平衡方面起着至关重要的作用,反过来又确保了肌肉的正常生长。研究为进一步阐明冷却滩羊肉贮藏中PI3K/AKT信号代谢稳态的分子机制提供了方向。

基于PI3K/AKT/GSK-3β信号通路探讨EA改善APP/PS1双转基因小鼠认知功能障碍的内在机制

目的探讨鞣花酸(ellagicacid,EA)对APP/PS1双转基因小鼠认知功能的影响,并基于磷脂酰肌醇3-激酶/蛋白激酶B/糖原合成酶激酶-3(PI3K/AKT/GSK-3β)信号通路探讨鞣花酸对双转基因小鼠海马氧化应激水平的调节机制。方法将32只SPF级6月龄APP/PS1双转基因小鼠随机分为4组,即APP/PS1组、APP/PS1+EA组、APP/PS1+LY294002组、APP/PS1+EA+LY294002组,每组8只,另外选取8只SPF级C57BL/6J野生型小鼠(Wildtype)作为空白对照组,即WT组。APP/PS1+EA组给予50mg·kg^(-1)·d^(-1)灌胃EA;APP/PS1+LY294002组予以1.5mg·kg^(-1)·d^(-1)腹腔注射PI3K抑制剂LY294002;APP/PS1+EA+LY294002组予以50mg·kg^(-1)·d^(-1)灌胃EA,同时按1.5mg·kg^(-1)·d^(-1)腹腔注射LY294002;WT组和APP/PS1组于相同时间点灌胃等体积10%二甲基亚砜(DMSO)。每日给药1次,连续给药60天。Morris水迷宫检测小鼠学习和记忆能力,免疫组化、蛋白免疫印迹法检测PI3K、AKT、GSK-3β相关蛋白的表达,透射电镜观察小鼠海马组织超微结构变化。结果与WT组相比,其他四组的逃避潜伏期均增长(P<0.05),穿越平台次数明显减少(P<0.01);APP/PS1组、APP/PS1+LY294002组和APP/PS1+EA+LY294002组中的PI3K、AKT蛋白表达量显著降低(P<0.01),GSK-3β表达量显著升高(P<0.01);APP/PS1+EA组的PI3K表达量降低(P<0.05),AKT表达量显著降低(P<0.01),GSK-3β表达量升高(P<0.05);与WT组相比,APP/PS1组海马神经元细胞数目较少,线粒体结构破坏,大部分线粒体出现肿胀,线粒体的内膜和外模不完整,部分线粒体嵴消失,微管、微丝缠结,排列紊乱,而APP/PS1+EA组神经元细胞数较APP/PS1组增多,线粒体结构较清晰,可见清楚的线粒体嵴,线粒体轻度水肿。微管、微丝排列较整齐有序。结论鞣花酸改善AD模型小鼠的学习和记忆能力、减少海马神经元细胞损伤和凋亡,其作用机制可能是通过调节PI3K、AKT、GSK-3β等相关蛋白降低AD模型小鼠海马氧化应激水平。

右美托咪定下调PI3K/AKT信号通路改善脂多糖诱导的结肠炎结肠上皮细胞损伤

为研究右美托咪定对脂多糖(LPS)诱导的人结肠上皮NCM-460细胞的炎症、增殖和凋亡的影响及磷脂酰肌醇-3-激酶/丝氨酸-苏氨酸激酶(PI3K/AKT)信号通路的调控作用,本研究体外培养人结肠上皮NCM-460细胞,将其分为对照组、LPS组(1μg/mL LPS)和不同质量浓度右美托咪定组(1μg/mL LPS+1.25、2.50、5.00和10.00μg/mL右美托咪定),干预24 h,筛选出合适的右美托咪定作用质量浓度用于后续试验。随后,将人结肠上皮NCM-460细胞分为对照组、LPS组、右美托咪定组(1μg/mL LPS+5.00μg/mL右美托咪定)、LY294002组(1μg/mL LPS+10μmol/L PI3K/AKT通路抑制剂LY294002)、抑制剂组(1μg/mL LPS+5.00μg/mL右美托咪定+10μmol/L LY294002)和激活剂组(1μg/mL LPS+5.00μg/mL右美托咪定+10μmol/L PI3K/AKT通路激动剂SC79),干预24 h。用细胞计数试剂盒-8(CCK-8)检测细胞活力;通过酶联免疫吸附试验(ELISA)检测肿瘤坏死因子-α(TNF-α)和白细胞介素-8(IL-8)的表达水平;用5-乙炔基-2'脱氧尿嘧啶核苷(EdU)测定细胞增殖率;用Hoechst 33258染色法测定细胞凋亡率;用蛋白免疫印迹(WB)法测定细胞周期蛋白D1(Cyclin D1)、剪切的半胱氨酸蛋白酶-3(cleaved Caspase 3)和PI3K/AKT信号通路关键蛋白的表达水平。根据细胞活力和炎症因子TNF-α的表达水平选择5.00μg/mL右美托咪定用于后续试验。结果显示,与对照组相比,LPS组细胞增殖率和Cyclin D1的表达水平显著降低(P<0.05),细胞凋亡率、TNF-α、IL-8、cleaved Caspase 3的表达水平、p-PI3K/PI3K及p-AKT/AKT的比值显著升高(P<0.05);右美托咪定组和LY294002组中的右美托咪定和LY294002扭转了LPS对人结肠上皮NCM-460细胞的上述作用(P<0.05);与右美托咪定组相比,抑制剂组中的LY294002增强了右美托咪定对LPS诱导的人结肠上皮NCM-460细胞的作用(P<0.05),激活剂组中的SC79则削弱了右美托咪定对LPS诱导的人结肠上皮NCM-460细胞的作用(P<0.05)。研究表明,右美托咪定能促进LPS诱导的人结肠上皮NCM-460细胞增殖,抑制其炎症和凋亡,其作用机制可能与阻滞PI3K/PI3K信号通路信号转导有关。本研究为结肠炎的治疗提供了新的方向。

miR-93-5p通过PI3K/AKT通路调控HepG2细胞自噬

目的:探究miR-93-5p对HepG2细胞增殖、自噬、葡萄糖消耗以及磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinases,PI3K)/蛋白激酶B(protein kinase B,AKT)通路的影响。方法:高浓度葡萄糖诱导构建胰岛素抵抗(insulin resistance,IR)细胞模型,设计合成miR-93-5p inhibitor和NC,结合自噬抑制剂3-MA,将细胞分为Control组、IR组、IR+inhibitor NC组、IR+inhibitor组、IR+3-MA+inhibitor组。CCK8法检测各组细胞增殖活力,试剂盒检测各组细胞葡萄糖消耗量和细胞糖原合成情况,Western-Blot法检测细胞自噬基因微管相关蛋白1轻链3(autophagy genes microtubule-associated protein 1 light chain 3,LC3)-I、LC3-II、肝细胞生长因子(hepatocyte growth factor,HGF)蛋白、PI3K/AKT通路蛋白(AKT、p-AKT)的表达。结果:与对照组相比,IR组细胞增殖活力、葡萄糖消耗量和细胞糖原合成量、HGF蛋白、LC3-II蛋白表达下降(P<0.01),LC3-I蛋白和p-AKT/AKT值表达均增加(P<0.01)。与IR组和IR+inhibitor NC组相比,IR+inhibitor组细胞增殖活力、葡萄糖消耗量和细胞糖原合成量、HGF蛋白、LC3-II蛋白表达增加(P<0.01),LC3-I蛋白和p-AKT/AKT值表达均下降(P<0.01)。与IR+inhibitor组相比,3-MA能逆转miR-93-5p inhibitor的作用。结论:miR-93-5p通过PI3K/AKT通路促进HepG2细胞自噬,进而抑制胰岛素抵抗,缓解糖尿病造成的机体损伤。

积雪草酸调节PI3K/AKT信号通路对七氟烷诱导的海马神经元HT-22细胞凋亡的影响

目的探讨积雪草酸(AA)通过调节磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/AKT)信号通路对七氟烷(SEVO)诱导的HT-22细胞凋亡的影响。方法使用不同浓度(0、5、10、15、20、30μmol/L)AA处理七氟烷诱导HT-22细胞24 h,CCK-8检测HT-22细胞活力;将HT-22细胞分为对照(Control)组、七氟烷(SEVO)组、AA低浓度(AA-L,10μmol/L)组、AA中浓度(AA-M,15μmol/L)组、AA高浓度(AA-H,20μmol/L)组和AA高浓度+PI13K通路抑制剂LY294002(AA-H+LY294002,20μmol/L AA+5μmol/L LY294002)组。显微镜下观察各组细胞形态变化,ELISA检测炎性因子肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)及氧化应激指标超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和丙二醛(MDA)水平,活性氧(ROS)试剂盒检测ROS水平,TUNEL试剂盒检测HT-22凋亡,JC-1法检测线粒体膜电位,三磷酸腺苷(ATP)含量检测试剂盒检测ATP含量,Western blot检测B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)、p-PI3K、PI3K、p-AKT和AKT蛋白表达。结果与0μmol/L相比,5~30μmol/L AA处理的HT-22细胞活力呈浓度依赖性升高(P<0.05),选择浓度为10、15、20μmol/L的AA用于后续实验。与SEVO组相比,AA-L组、AA-M组和AA-H组TNF-α、IL-6、MDA和ROS水平、细胞凋亡率、Bax和Caspase-3蛋白表达降低,SOD和GSH-Px水平、红/绿JC-1荧光比、ATP含量、Bcl-2蛋白表达、PI3K和AKT磷酸化水平增加(P<0.05),且呈浓度依赖性。LY294002可逆转AA对七氟烷诱导的HT-22细胞损伤的保护作用(P<0.05)。结论AA通过激活PI3K/AKT信号通路保护七氟烷诱导的HT-22细胞损伤,为新型减轻七氟烷诱导的神经毒性的药物开发提供了一定的理论参考。

PI3K/Akt信号通路通过上调HKDC1促进人肝癌HepG2细胞糖酵解、增殖及迁移

目的探讨磷脂酰肌醇-3-激酶/蛋白激酶B(PI3K/Akt)通过调节含己糖激酶结构域的蛋白1(HKDC1)对人肝癌HepG2细胞糖酵解、增殖和迁移的影响及机制。方法将体外培养的对数期人肝癌HepG2细胞,分为对照组、LY294002组和MK-2206组,RT-qPCR法检测各组细胞HKDC1 mRNA的表达水平,western blotting法分析各组细胞HKDC1蛋白的表达水平。将细胞分为si-NC组(转染si-NC)、si-HKDC1组(转染si-HKDC1),western blotting法分析各组细胞HKDC1蛋白的表达水平,CCK-8、5-乙炔基-2′-脱氧尿苷(EdU)实验检测各组细胞增殖活力和划痕,Transwell实验检测各组细胞迁移率,细胞外酸化率(ECAR)实验检测分析各组细胞的糖酵解和糖酵解能力,葡萄糖及乳酸含量测定实验检测各组细胞内葡萄糖及乳酸含量。将细胞分为对照组、LY294002组、过表达HKDC1+LY294002组、MK-2206组、过表达HKDC1+MK-2206组,葡萄糖及乳酸含量测定实验检测各组细胞内葡萄糖及乳酸含量。结果与对照组比较,LY294002组细胞HKDC1 mRNA表达明显降低(P<0.001),HKDC1蛋白表达降低(P<0.01);MK-2206组细胞HKDC1 mRNA表达降低(P<0.01),HKDC1蛋白表达明显降低(P<0.001)。与si-NC组相比,si-HKDC1组细胞HKDC1蛋白表达降低(P<0.001);与si-NC组相比,si-HKDC1组细胞增殖活力降低(P<0.05),EdU阳性细胞数明显减少(P<0.01);与si-NC组相比,si-HKDC1组细胞划痕愈合率明显降低(P<0.001),迁移细胞数明显减少(P<0.001);与si-NC组相比,si-HKDC1组细胞糖酵解和糖酵解能力明显减弱(P<0.01);与si-NC组相比,si-HKDC1组细胞内葡萄糖和乳酸含量明显降低(P<0.05)。与LY294002组相比,过表达HKDC1+LY294002组细胞内葡萄糖和乳酸含量明显升高(P<0.01);与MK-2206组相比,过表达HKDC1+MK-2206组细胞内葡萄糖和乳酸含量明显升高(P<0.001,P<0.01)。结论PI3K/Akt信号通路通过HKDC1促进人肝癌HepG2细胞糖酵解、增殖和迁移。

Yes相关蛋白(YAP)通过激活PI3K/AKT通路促进皮肤鳞状细胞癌细胞侵袭和迁移

目的探讨Yes相关蛋白(YAP)在皮肤鳞状细胞癌(cSCC)中表达及与cSCC侵袭和迁移中的作用。方法通过免疫组织化学染色法检测cSCC、鲍温病(BD)、癌旁正常皮肤组织中YAP的表达水平,并分析与临床病理参数之间的关系;利用慢病毒转染构建YAP基因敲低的A431稳定细胞株,利用四甲基罗丹明标记的鬼笔环肽检测A431细胞微丝分布和数量,Transwell TM实验检测细胞侵袭能力,划痕实验检测A431细胞的迁移能力;免疫荧光细胞化学染色法观察敲低YAP后上皮间质转化(EMT)相关标志物上皮钙黏素(E-cadherin)、锌指转录因子Snail的表达;Western blot法检测E-cadherin、Snail、β-catenin、磷脂酰肌醇3激酶(PI3K)、蛋白激酶B(AKT)、磷酸化的蛋白激酶B(p-AKT)、核糖体蛋白S6(S6)、磷酸化S6(p-S6)、4E结合蛋白1(4EBP1)、磷酸化的4EBP1(p-4EBP1)的表达。结果YAP在cSCC和BD中表达显著高于癌旁正常皮肤组织;cSCC中YAP高表达与肿瘤大小、分化程度、侵袭程度密切相关,与患者的性别、年龄、发病部位、形态类型、是否神经脉管侵犯不相关;敲低A431细胞中YAP后,肿瘤细胞的侵袭、迁移能力降低,细胞微丝变细、伪足变少;E-cadherin表达增加,Snail和β-catenin蛋白表达降低,p-AKT、p-S6及p-4EBP1蛋白表达降低。结论YAP在cSCC中高表达,YAP激活PI3K/AKT信号通路促进cSCC的侵袭、迁移及EMT过程。

黄芩素对人乳腺癌细胞系MDA-MB-231侵袭、迁移、上皮间充质转化的调控作用及其机制

目的观察黄岑素对人乳腺癌细胞系MDA-MB-231的侵袭、迁移及上皮间充质转化(EMT)的调控作用,探讨其可能作用机制。方法取对数生长期MDA-MB-231细胞分为一组、二组、三组及对照组,一组、二组、三组分别加入2.5、5、10μmol/L的黄岑素,对照组不做任何处理。培养48 h时采用划痕修复实验观察四组细胞迁移能力、采用Transwell侵袭实验观察四组细胞侵袭能力,采用Western Blotting法检测细胞EMT标志物波形蛋白(vimentin)及E-钙黏蛋白(E-cadherin)、整合素αv、β3、磷酸化黏着斑激酶(p-FAK)、磷酸化磷脂酰肌醇3激酶(整合素p-PI3K)。结果与对照组相比,黄岑素组细胞迁移率降低、侵袭细胞数少,细胞E-cadherin相对表达量高,vimentin、整合素αv、整合素β3、p-FAK、p-PI3K蛋白相对表达量低,且呈剂量依赖性(P均<0.05)。结论黄芩素抑制MDA-MB-231细胞的侵袭、迁移及EMT。黄岑素可能通过抑制整合素αv、整合素β3表达,进一步抑制p-FAK、p-PI3K蛋白表达,抑制MDA-MB-231的侵袭、迁移及EMT。

秋水仙碱通过激动PI3K/AKT/eNOS信号通路对急性心肌梗死大鼠心功能的影响

目的:探究秋水仙碱通过调节磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/内皮型一氧化氮合酶(eNOS)信号通路对急性心肌梗死(AMI)大鼠心功能的影响。方法:78只大鼠中随机选取12只作为假手术组,剩余大鼠构建AMI模型,造模成功大鼠分为模型组、秋水仙碱组[4 mg/(kg·d)]、秋水仙碱[4 mg/(kg·d)]+LY294002(20 mg/mL)组、秋水仙碱[4 mg/(kg·d)]+MK-2206(60μg/mL)组、秋水仙碱[4 mg/(kg·d)]+L-NAME(1.6 mg/mL)组,每组12只。超声心动图检测大鼠左心室舒张末期内径(LVEDD)、左心室收缩末期内径(LVESD)、射血分数(EF)及短轴缩短率(FS)。处死大鼠,苏木素-伊红(HE)染色检测大鼠心肌组织石蜡切片病理学变化;末端脱氧核苷酸转移酶介导的dUTP缺口末端标记(TUNEL)法检测心肌细胞凋亡率;酶联免疫吸附实验(ELISA)测定大鼠血清肿瘤坏死因子α(TNF-α)、白细胞介素-6(IL-6)、肌酸激酶同工酶(CK-MB)以及心肌组织匀浆中超氧化物歧化酶(SOD)、丙二醛(MDA)、过氧化氢酶(CAT)水平;免疫印迹法(Western Blot)测定大鼠心肌组织PI3K/AKT/eNOS通路蛋白表达。结果:与假手术组相比,模型组大鼠LVESD、LVEDD,血清CK-MB、TNF-α、IL-6水平,心肌匀浆MDA、心肌细胞凋亡率升高,EF、FS水平,心肌匀浆SOD、CAT,心肌组织磷酸化PI3K(p-PI3K)/PI3K、磷酸化AKT(p-AKT)/AKT、磷酸化eNOS(p-eNOS)/eNOS降低(P<0.05);与模型组相比,秋水仙碱组大鼠LVESD、LVEDD,血清CK-MB、TNF-α、IL-6水平,心肌匀浆MDA、心肌细胞凋亡率降低,EF、FS水平,心肌匀浆SOD、CAT,心肌组织p-PI3K/PI3K、p-AKT/AKT、p-eNOS/eNOS升高(P<0.05);与秋水仙碱组相比,秋水仙碱+LY294002组、秋水仙碱+MK-2206组、秋水仙碱+L-NAME组大鼠LVESD、LVEDD,血清CK-MB、TNF-α、IL-6水平,心肌匀浆MDA、心肌细胞凋亡率升高,EF、FS水平,心肌匀浆SOD、CAT,心肌组织p-PI3K/PI3K、p-AKT/AKT、p-eNOS/eNOS降低(P<0.05)。结论:秋水仙碱可能通过激活PI3K/AKT/eNOS信号通路对AMI大鼠发挥心功能保护作用。