Hypoglycemic mechanism of Tegillarca granosa polysaccharides on type 2 diabetic mice by altering gut microbiota and regulating the PI3K-akt signaling pathwaye

Type 2 diabetes mellitus(T2DM)is a complex metabolic disease threatening human health.We investigated the effects of Tegillarca granosa polysaccharide(TGP)and determined its potential mechanisms in a mouse model of T2DM established through a high-fat diet and streptozotocin.TGP(5.1×10^(3) Da)was composed of mannose,glucosamine,rhamnose,glucuronic acid,galactosamine,glucose,galactose,xylose,and fucose.It could significantly alleviate weight loss,reduce fasting blood glucose levels,reverse dyslipidemia,reduce liver damage from oxidative stress,and improve insulin sensitivity.RT-PCR and Western blotting indicated that TGP could activate the phosphatidylinositol-3-kinase/protein kinase B signaling pathway to regulate disorders in glucolipid metabolism and improve insulin resistance.TGP increased the abundance of Allobaculum,Akkermansia,and Bifidobacterium,restored the microbiota abundance in the intestinal tracts of mice with T2DM,and promoted short-chain fatty acid production.This study provides new insights into the antidiabetic effects of TGP and highlights its potential as a natural hypoglycemic nutraceutical.

Spi1 regulates the microglial/macrophage inflammatory response via the PI3K/AKT/mTOR signaling pathway after intracerebral hemorrhage

Preclinical and clinical studies have shown that microglia and macrophages participate in a multiphasic brain damage repair process following intracerebral hemorrhage.The E26 transformation-specific sequence-related transcription factor Spi1 regulates microglial/macrophage commitment and maturation.However,the effect of Spi1 on intracerebral hemorrhage remains unclear.In this study,we found that Spi1 may regulate recovery from the neuroinflammation and neurofunctional damage caused by intracerebral hemorrhage by modulating the microglial/macrophage transcriptome.We showed that high Spi1expression in microglia/macrophages after intracerebral hemorrhage is associated with the activation of many pathways that promote phagocytosis,glycolysis,and autophagy,as well as debris clearance and sustained remyelination.Notably,microglia with higher levels of Soil expression were chara cterized by activation of pathways associated with a variety of hemorrhage-related cellular processes,such as complement activation,angiogenesis,and coagulation.In conclusion,our results suggest that Spi1 plays a vital role in the microglial/macrophage inflammatory response following intracerebral hemorrhage.This new insight into the regulation of Spi1 and its target genes may advance our understanding of neuroinflammation in intracerebral hemorrhage and provide therapeutic targets for patients with intracerebral hemorrhage.

ROR2 promotes invasion and chemoresistance of triple-negative breast cancer cells by activating PI3K/AKT/mTOR signaling

Objective:This study aimed to investigate the role of receptor tyrosine kinase-like orphan receptor 2(ROR2)in triple-negative breast cancer(TNBC).Methods:ROR2 expression in primary TNBC and metastatic TNBC tissues was analyzed by immunohistochemical staining and PCR.ROR2 expression in TNBC cell lines was detected by PCR and Western blot analysis.The migration,invasion and chemosensitivity of TNBC cells with overexpression or knockdown of ROR2 were examined.Results:ROR2 expression was high in metastatic TNBC tissues.ROR2 knockdown suppressed the migration,invasion and chemoresistance of TNBC cells.ROR2 overexpression in MDA-MB-435 cells promoted the migration,invasion,and chemoresistance.Moreover,ROR2 knockdown in HC1599 and MDA-MB-435 adriamycin-resistant cells enhanced chemosensitivity to adriamycin.ROR2 could activate PI3K/AKT/mTOR signaling in TNBC cells.Conclusion:ROR2 is upregulated and promotes metastatic phenotypes of TNBC by activating PI3K/AKT/mTOR signaling.

彝药痹Ⅱ号介导KLF2调控PI3K/Akt/mTOR通路对类风湿性关节炎小鼠模型表达及生物学行为特性影响的机制研究

目的:探讨彝药痹Ⅱ号介导KLF2调控PI3K/Akt/mTOR通路对类风湿性关节炎小鼠模型表达及生物学行为特性影响的机制。方法:80只昆明种小鼠分为对照组、模型组、彝药痹Ⅱ号组低、高剂量组;除对照组外,其余各组通过左后足趾皮内注射弗氏完全佐剂建立小鼠RA模型;彝药痹Ⅱ号组低、高剂量组于造模成功第1天开始给予相应剂量药物灌胃,持续给予3个月,对照组和模型组给予等体积生理盐水。试验结束后测定小鼠PEL、关节炎症积分、足趾容积;RT-PCR法、蛋白印迹法、免疫组化法测定小鼠踝关节软骨KLF2、PI3K、Akt、mTOR水平。结果:模型组小鼠PEL低于对照组,关节炎症积分、足趾容积高于对照组(P<0.05);彝药痹Ⅱ号低、高剂量组小鼠PEL高于对照组,关节炎症积分、足趾容积低于对照组(P<0.05);且随着彝药痹Ⅱ号剂量的逐渐升高,各剂量组小鼠PEL逐渐升高,关节炎症积分、足趾容积逐渐降低(P<0.05)。模型组小鼠踝关节KLF2、PI3K、Akt、mTOR mRNA和蛋白表达水平高于对照组(P<0.05);与模型组比较,彝药痹Ⅱ号低、高剂量组小鼠踝关节KLF2、PI3K、Akt、mTOR mRNA和蛋白表达水平低于对照组(P<0.05);且随着彝药痹Ⅱ号剂量的逐渐升高,各剂量组小鼠踝关节KLF2、PI3K、Akt、mTOR mRNA和蛋白表达水平逐渐降低(P<0.05)。结论:彝药痹Ⅱ号对小鼠类风湿性关节炎具有明显治疗作用,能明显抑制小鼠踝关节软骨滑膜炎症反应;其机制与彝药痹Ⅱ号抑制类风湿性关节炎小鼠踝关节软骨炎症KLF2-PI3K-Akt-mTOR通路的激活有关。

Campanumoea javanica Bl. activates the PI3K/AKT/mTOR signaling pathway and reduces sarcopenia in a T2DM rat model

Objective: Sarcopenia causes loss of skeletal muscle and function, thus seriously affecting the physical function and quality of life in the elderly. This article discusses the specific molecular mechanism and ameliorating effects of Tudangshen(TDS) on sarcopenia in elderly rats with type 2 diabetes mellitus(T2DM).Methods: Elderly Sprague-Dawley(SD) rats were randomly selected and fed with a high-fat diet combined with an intraperitoneal injection of streptozotocin to establish T2DM model. The model rats were stratified and randomly divided into the model group,metformin group, TDS high-dose group, TDS medium-dose group, and TDS low-dose group according to blood glucose combined with body weight, and the same batch of old SD rats was set as the normal control group. The effects of TDS in an elderly T2DM sarcopenia rat model were evaluated by observing the body positions of the rats, analyzing blood biochemistry, testing exercise capacity, and pathologically staining sectioned gastrocnemius muscle tissues. The molecular mechanisms of the effects were analyzed using quantitative real-time polymerase chain reaction and western blotting.Results: TDS has no statistically significant effect on blood glucose, insulin and glycosylated serum protein in aged rats with T2DM, but it can reduce levels of glycosylated serum protein, total cholesterol, triglycerides, and low-density lipoprotein;it improves pathological changes in rat gastrocnemius muscle tissues, and increases muscle cell activity in elderly rats with T2DM and sarcopenia. TDS also promoted the upregulation of the expression of mammalian target of rapamycin(mTOR)/protein kinase B(PKB/AKT)/phosphatidylinositol 3-kinase(PI3K)/ribosomal protein S6 kinase/eukaryotic initiation factor 4 E binding rotein1 mRNA in rats and triggered an increase in corresponding protein levels.Conclusions: TDS alleviated muscle decline in elderly rats with T2DM by activating the PI3 K/AKT/mTOR signaling pathway and regulating the synthesis of corresponding proteins.

Melatonin improves synapse development by PI3K/Akt signaling in a mouse model of autism spectrum disorder

Autism spectrum disorders are a group of neurodevelopmental disorders involving more than 1100 genes,including Ctnnd2 as a candidate gene.Ctnnd2knockout mice,serving as an animal model of autis m,have been demonstrated to exhibit decreased density of dendritic spines.The role of melatonin,as a neuro hormone capable of effectively alleviating social interaction deficits and regulating the development of dendritic spines,in Ctnnd2 deletion-induced nerve injury remains unclea r.In the present study,we discove red that the deletion of exon 2 of the Ctnnd2 gene was linked to social interaction deficits,spine loss,impaired inhibitory neurons,and suppressed phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt) signal pathway in the prefrontal cortex.Our findings demonstrated that the long-term oral administration of melatonin for 28 days effectively alleviated the aforementioned abnormalities in Ctnnd2 gene-knockout mice.Furthermore,the administration of melatonin in the prefro ntal cortex was found to improve synaptic function and activate the PI3K/Akt signal pathway in this region.The pharmacological blockade of the PI3K/Akt signal pathway with a PI3K/Akt inhibitor,wo rtmannin,and melatonin receptor antagonists,luzindole and 4-phenyl-2-propionamidotetralin,prevented the melatonin-induced enhancement of GABAergic synaptic function.These findings suggest that melatonin treatment can ameliorate GABAe rgic synaptic function by activating the PI3K/Akt signal pathway,which may contribute to the improvement of dendritic spine abnormalities in autism spectrum disorders.

PI3K/AKT/mTOR signaling pathway inhibitors in proliferation of retinal pigment epithelial cells

AIM: To determine whether the PI3K/AKT/mTOR pathway is activated in proliferative vitreoretinopathy (PVR) in homo-sapiens. METHODS: The retina of controls and patients with PVR were collected and their levels of PI3K, phospho-AKT, phospho-mTOR, phospho-p70S6k and phospho-4EBP-1 were determined by Western blot. The cultured human retinal pigment epithelial cell line D407 was treated with a specific mTOR inhibitor, rapamycin (RAPA) or a PI3K inhibitor, LY294002, of various concentrations and durations. Cell morphology was observed by phase contrast microscopy and the proliferation and apoptosis of treated cells were determined by MTT assay and flow cytometry. RESULTS: Levels of PI3K, phospho-AKT, phospho-mTOR, phospho-P70S6K and phospho-4EBP1 was increased in the retina in PVR (P <0.05). In D407 cells, both RAPA and LY294002 significantly inhibited cell proliferation and cell cycle progression, and promoted apoptosis (P <0.05); morphologically, the cells became smaller. Both RAPA and LY294002 reduced levels of phospho-AKT, phospho-mTOR, phospho-p70S6k and phospho-4EBP1 expression (P <0.05). RAPA, but not LY294002, had no significant effect on PI3K expression. CONCLUSION: PI3K/AKT/mTOR signaling pathway is highly activated in the retinal pigment epithelial cells of PVR. The inhibitors of PI3K/AKT/mTOR signaling pathway, RAPA and LY294002, could inhibited the PI3K/AKT/mTOR signaling pathway by reducing the levels of phosphorylation of mTOR pathway components.

Alleviatory effect of isoquercetin on benign prostatic hyperplasia via IGF-1/PI3K/Akt/mTOR pathway

We evaluated the effect of isoquercetin(quercetin-O-3-glucoside-quercetin,IQ)as a functional component of Abeliophyllum disistichum Nakai ethanol extract(ADLE)on prostate cell proliferation and apoptosis and its effects on the IGF-1/PI3K/Akt/mTOR pathway in benign prostatic hyperplasia(BPH).Metabolites in ADLE were analyzed using UHPLC-qTOF-MS and HPLC.IQ was orally administered(1 or 10 mg/kg)to a testosterone propionate-induced BPH rat model,and its effects on the prostate weight were evaluated.The effect of IQ on androgen receptor(AR)signaling was analyzed in LNCaP cells.Whether IGF-1 and IQ affect the IGF-1/PI3K/Akt/mTOR pathway in BPH-1 cells was also examined.The metabolites in ADLE were identified and quantified,which confirmed that ADLE contained abundant IQ(20.88 mg/g).IQ significantly reduced the prostate size in a concentration-dependent manner in a BPH rat model,and significantly decreased the expression of AR signaling factors in the rat prostate tissue and LNCaP cells in a concentration-dependent manner.IQ also inhibited the PI3K/AKT/mTOR pathway activated by IGF-1 treatment in BPH-1 cells.In BPH-1 cells,IQ led to G0/G1 arrest and suppressed the expression of proliferation factors while inducing apoptosis.Thus,IQ shows potential for use as a pharmaceutical and nutraceutical for BPH.

Acetylshikonin Inhibits Colorectal Cancer Growth via PI3K/Akt/mTOR Signaling Pathway

Background: Acetylshikonin, a major constituent isolated from Arnebia euchroma, is a potential candidate for anti-colorectal cancer drugs. However, the potential activity and underlying mechanism of Acetylshikonin against colorectal cancer remain unclear. Methods: In this study, Acetylshikonin was isolated from the active CHCl3 extract of Arnebia euchroma using activity-guided screening, and elucidated by the extensive spectroscopic analysis and comparison with literature data. Human colorectal cancer cells HT29, DLD-1, HCT116 or Caco-2 were exposed to different concentrations of Acetylshikonin (6.25 - 100 μg/mL) for 24 or 48 h. Cell viability, cell apoptosis and cell cycle distribution were detected. The activity of Acetylshikonin and potential mechanism of the phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway were evaluated in vitro and vivo. Results: We found that Acetylshikonin exhibited remarkable anti-proliferative activity in a dose-dependent manner against HT29 cells with the IC50 values of 60.82 μg/ml and 30.78 μg/ml at 24, 48 h, respectively. Moreover, Acetylshikonin induced cell cycle arrest at G0/G1 phase and early apoptosis through inhibition of PI3K/Akt/mTOR pathway. Furthermore, the assays of cell inhibition, early apoptosis and G0/G1 phase distribution showed that suppression of the PI3K/Akt pathway using LY294002 enhanced the anti-cancer effect of Acetylshikonin. Similarly, Acetylshikonin also decreased the growth of tumour in colorectal cancer xenografts in mice through PI3K/Akt/mTOR pathway. Conclusions: To sum up, these new findings provided a framework for further exploration of Acetylshikonin which possessed the potential antitumor activity by inhibiting PI3K/Akt/mTOR pathway.

FGF2 promotes the chemotherapy resistance in colon cancer cells through activating PI3K/Akt signaling pathway

Background:To investigate the role of fibroblast growth factor 2(FGF2)in chemotherapy resistance of colon cancer.Methods:An HCT116/5-fluorouracil(5-FU)-resistant cell line was established,and FGF2 levels were detected in a sensitive cell group(HCT116)and a resistant cell group(HCT1116-R)using different methods.Fibroblast growth factor 2 levels in the medium were determined by enzyme-linked immunoassay.The protein expressions of FGF2,fibroblast growth factor receptor 1(FGFR1),and phospho-FGFR1 were assessed by Western blotting,and FGF2 mRNA levels were detected by quantitative real-time polymerase chain reaction.Fibroblast growth factor 2 recombinant protein was added to sensitive cells,and FGFR inhibitor AZD4547 was added to resistant cells,and the cell survival rate was determined using the cell counting kit-8 method and the protein expressions of PI3K(phosphatidylinositol 3 kinase),p-PI3K(phospho-PI3K),Akt(protein kinase B),p-Akt(phospho-Akt),mammalian target of rapamycin(mTOR),p-mTOR(phospho-mTOR),Bad(Bcl-xL/Bcl-2-associated death promoter),NF-κB(nuclear factorκB),GSK-3(glycogen synthase kinase-3),FKHR(forkhead box protein O1),and PTEN(phosphatase and tensin homolog deleted on chromosome ten)were detected by Western blotting.Results:Fibroblast growth factor 2 protein and mRNA expression levels in the HCT116-R group were significantly higher than those in the HCT116 group.Fibroblast growth factor 2 increased the survival rate of HCT116 cells;improved tolerance to 5-FU;upregulated p-PI3K,p-Akt,and p-mTOR;and downregulated Bad.The FGFR inhibitor AZD4547 decreased cell survival rate and tolerance to 5-FU;downregulated p-PI3K,p-Akt,and p-mTOR expression;and upregulated Bad.Conclusions:Fibroblast growth factor 2 promotes chemotherapy tolerance in colon cancer cells by activating the Akt/mTOR and Akt/Bad signaling pathways downstream of PI3K.

PKM2通过调控活性氧依赖的PI3K/Akt信号通路影响膀胱尿路上皮细胞癌细胞的侵袭能力

目的 探讨PKM2通过调控活性氧(ROS)依赖的PI3K/Akt信号通路对膀胱尿路上皮细胞癌细胞侵袭能力的影响。方法 将人膀胱癌T24细胞随机分为Control组、si-NC组、si-PKM2组和si-PKM2+IGF-1组。实时PCR检测细胞中PKM2 mRNA表达;CCK-8检测细胞增殖;Transwell小室法检测细胞侵袭和转移;Hoechst 33342荧光染色和流式细胞术检测细胞凋亡;ROS荧光探针法检测细胞中ROS水平;Western blotting检测细胞中PI3K、Akt、mTOR、caspase-3、Bax、Bcl-2蛋白表达。结果 与人正常膀胱上皮SV-HUC-1细胞相比,人膀胱癌T24细胞中PKM2 mRNA相对表达量明显增加(P <0.05)。与Control组相比,si-PKM2组T24细胞中PKM2 mRNA相对表达量、细胞增殖能力、侵袭细胞数以及细胞中p-PI3K/PI3K、p-Akt/Akt、p-mTOR/mTOR比值和Bcl-2蛋白表达水平明显降低(P <0.05),细胞凋亡率、细胞中ROS相对水平以及细胞中Bax、caspase-3蛋白表达水平明显升高(P <0.05);与siPKM2组相比,si-PKM2+IGF-1组T24细胞中PKM2 mRNA相对表达量、细胞增殖能力、侵袭细胞数以及细胞中p-PI3K/PI3K、p-Akt/Akt、p-mTOR/mTOR比值和Bcl-2蛋白表达水平明显升高(P <0.05),细胞凋亡率、细胞中ROS相对水平以及细胞中Bax、caspase-3蛋白表达水平明显降低(P <0.05)。结论 敲减PKM2可促进膀胱尿路上皮细胞癌细胞中ROS水平升高,抑制PI3K/Akt/mTOR信号通路激活,进而发挥抑制细胞侵袭和促进细胞凋亡作用。

MiR-30e-3p inhibits gastric cancer development by negatively regulating THO complex 2 and PI3K/AKT/mTOR signaling

BACKGROUND Gastric cancer(GC)is a common type of digestive cancer with high morbidity and mortality rates worldwide.Considerable effort has been expended in understanding the mechanism of GC development and metastasis.The current study therefore explores the involvement of microRNAs in the regulation of GC progression.AIM To explore the expression and function of miR-30e-3p in GC development.METHODS MiR-30e-3p was found to be downregulated in GC,with low levels thereof predicting poor outcomes among patients with GC.Functionally,we revealed that miR-30e-3p suppressed cell growth and metastatic behaviors of GC cells.Bioinformatics analysis predicted that THO complex 2(THOC2)was a direct target of miR-30e-3p,and the interaction between miR-30e-3p and THOC2 was further validated by a luciferase reporter assay.RESULTS Our findings revealed that knockdown of THOC2 inhibited the growth and metastatic behaviors of GC cells.After investigating signaling pathways involved in miR-30e-3p regulation,we found that the miR-30e-3p/THOC2 axis regulated the PI3K/AKT/mTOR pathway in GC.CONCLUSION Our findings suggest the novel functional axis miR-30e-3p/THOC2 is involved in GC development and progression.The miR-30e-3p/THOC2 axis could be utilized to develop new therapies against GC.

Effects of Liancao-Xieli capsule on intestinal mucosal inflammatory factors and TLR4/PI3K/Akt/mTOR signaling pathway in mice with ulcerative colitis

Objective:To observe the effect of Liancao-Xieli capsule on intestinal mucosal inflammatory factors and TLR4/PI3K/Akt/mTOR signaling pathway in mice with ulcerative colitis(UC);Methods:40 male C57BL/6 mice were randomly divided into the control group,model group,Liancao-Xieli group and mesalazine group,with 10 mice in each group.In addition to the control group,the remaining three groups of mice were induced by 3%dextran sulfate sodium(DSS)to induce acute UC model.During the modeling period,mice in each group were given corresponding drugs and normal saline by gavage.At the end of the experiment,HE staining was used to observe the pathological changes of colonic tissue in each group,and ELISA was used to detect the inflammatory factors(TNF-α,IL-6,IL-1β,IL-8,IL-17,and INF-γ)in serum and colonic tissue.The expression levels of TLR4/PI3K/Akt/mTOR signaling pathway related proteins were also detected by Western blot;Results:Compared with the model group,Liancao-Xieli capsule could significantly increase the colon length and decrease the score of colon histopathology in UC mice(P<0.01).In addition,the levels of TNF-α,IL-6,IL1β,IL-8,IL-17,and INF-γwere significantly reduced in serum and colon tissue,and the expressions of TLR4,PI3K,p-Akt and p-mTOR were significantly down-regulated in LiancaoXieyi group when compared with the model group(P<0.01).While the expressions of Akt and mTOR were not significantly affected in Liancao-Xieyi group(P>0.05);Conclusion:LiancaoXieli capsule can reduce the secretion of inflammatory factors,improve the intestinal mucosal damage and inflammatory response in UC by inhibiting the activation of TLR4/PI3K/Akt/mTOR signaling pathway。

A study of acupoint specificity and mechanism of electroacupuncture intervention on chronic colitis in rats based on PI3K/AKT/mTOR signaling pathway

Objective:This study aimed to elucidate the differences in effects and mechanisms of action of electric-needle therapy at Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)acupoints on chronic experimental colitis in rats through the PI3K/AKT/mTOR signaling pathway.Methods:Sixty pathogen-free SD rats were randomly assigned to six groups:the normal,model,Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)groups,each with 10 rats.Chronic colitis was induced in rats by combining immunization and local stimulation.After model establishment,electrical needle intervention combined with dispersing wave of 2 Hz/50 Hz with a current intensity of 2 mA once daily for 20 min was applied on acupoints of each group.Subsequently,the inflammation of colonic mucosa and serum levels of inflammatory factors(IL-23,IL-17,IL-10)were observed;ELISA was used to detect mRNA expressions of PI3K,Akt and mTOR in colitic tissues by RT-PCR as well as protein content of p-PI3k/PI3K,p-Akt/Akt,and p-mTOR/mTOR in colitic tissues by Western blotting.Result:Compared with the normal group,the model rats showed a poor general condition,serious damage to the colonic mucosa with a large number of inflammatory cells infiltration.The serum IL-23 and IL-17 expressions were significantly increased(P<0.01),while the serum IL-10 expression was significantly decreased(P<0.01);the mRNA and protein expressions of PI3K,Akt,mTOR and p-PI3K,p-Akt and p-mTOR were significantly increased(P<0.05,P<0.01).Compared with the model group,the pathological slices of rats in each acupoints intervention group showed obvious improvement of colitis inflammatory reaction and tissue damage;the serological levels of IL-23 and IL-17 were significantly reduced(P<0.01),while the serology level of IL-10 was significantly increased(P<0.01);the expressions of PI3K,Akt,mTOR mRNA and p-PI3K,p-Akt,p-mTOR proteins were significantly decreased(P<0.05,P<0.01).Compared with Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)groups,the recovery degree of mucosa layers in Shang Ju Xu(ST37)group was closer to that of normal group,and the curative effect was relatively the best;in terms of serological levels of IL-23 and IL-17,the Shang Ju Xu(ST37)group was significantly lower(P<0.05),while the level of IL-10 was significantly higher(P<0.01);the expressions of PI3K,Akt,mTOR mRNA and p-PI3K,p-Akt,p-mTOR proteins were significantly decreased(P<0.05,P<0.01).Conclusion:Results indicate that electrical acupuncture at Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)show similar effects in relieving the colitis-induced damage in the mucosa of chronic colitis rats,as well as inflammatory response.Among them,Shang Ju Xu(ST25)has a superior overall effect in treating chronic colitis compared to Tian Shu(ST25),Da Chang Shu(BL25)and Zu San Li(ST36).The mechanism may be related to inhibition of PI3K/Akt/mTOR signaling pathway.

Luteolin affects the EMT transformation and cell biological behavior of osteosarcoma U2OS cells via the PI3K/AKT/NF-κB signaling pathway

Objective:To investigate the effect of luteolin on the Epithelial-mesenchymal transition(EMT)of osteosarcoma cell line U2OS and its molecular mechanism by regulating phosphoinositide 3-kinase/protein kinase B/nuclear factor-kappa B(PI3K/AKT/NF-κB)signaling pathway.Methods:U2OS cells were treated in different concentrations(10,20 and 40μmol/L)of luteolin.MTT was used to detect the effect of luteolin on the proliferation of osteosarcoma U2OS cells.Transwell chamber assay was used to detect the influence of luteolin on migration of U2OS cells.qPCR was used to detect the influence of luteolin on the mRNA expression of Bax,Bcl-2 and Caspase-2 in U2OS cells.Western blot was used to observe the change of p-PI3K,p-AKT,p-IKK and NF-κB proteins.Immunofluorescence was used to detect the influence of luteolin on the protein expression of E-cadherin and vimentim.Results:Luteolin inhibited significantly the proliferation of U2OS cells(P<0.05)in a time-concentration-dependent manner.Luteolin inhibited significantly the migration of U2OS cells(P<0.05).After treatment with luteolin,the mRNA expression of Bax and Caspase-2 was increased significantly(P<0.05),but Bcl-2 was reduced significantly(P<0.05)in U2OS cells.The protein expression of p-PI3K,p-AKT,p-IKK,NF-κB,E-cadherin and vimentin was decreased significantly(P<0.05).Conclusions:Luteolin inhibits the proliferation,migration and EMT transformation of osteosarcoma U2OS cells,which may be related to the inhibition of PI3K/AKT/NF-κB signaling pathway.

Baicalin attenuates blood-spinal cord barrier disruption and apoptosis through PI3K/Akt signaling pathway after spinal cord injury

Baicalin is a natural active ingredient isolated from Scutellariae Radix that can cross the blood-brain barrier and exhibits neuroprotective effects on multiple central nervous system diseases.However,the mechanism behind the neuroprotective effects remains unclear.In this study,rat models of spinal cord injury were established using a modified Allen's impact method and then treated with intraperitoneal injection of Baicalin.The results revealed that Baicalin greatly increased the Basso,Beattie,Bresnahan Locomotor Rating Scale score,reduced blood-spinal cord barrier permeability,decreased the expression of Bax,Caspase-3,and nuclear factorκB,increased the expression of Bcl-2,and reduced neuronal apoptosis and pathological spinal cord injury.SH-SY5 Y cell models of excitotoxicity were established by application of 10 m M glutamate for 12 hours and then treated with 40μM Baicalin for 48 hours to investigate the mechanism of action of Baicalin.The results showed that Baicalin reversed tight junction protein expression tendencies(occludin and ZO-1)and apoptosis-related protein expression(Bax,Bcl-2,Caspase-3,and nuclear factor-κB),and also led to up-regulation of PI3 K and Akt phosphorylation.These effects on Bax,Bcl-2,and Caspase-3 were blocked by pretreatment with the PI3 K inhibitor LY294002.These findings suggest that Baicalin can inhibit bloodspinal cord barrier permeability after spinal cord injury and reduce neuronal apoptosis,possibly by activating the PI3 K/Akt signaling pathway.This study was approved by Animal Ethics Committee of Xi'an Jiaotong University on March 6,2014.

Eukaryotic elongation factor-1α 2 knockdown inhibits hepatocarcinogenesis by suppressing PI3K/Akt/NF-κB signaling

AIM: To assess the impact of eukaryotic elongation factor 1 alpha 2 (eEF1A2) on hepatocellular carcinoma (HCC) cell proliferation, apoptosis, migration and invasion, and determine the underlying mechanisms.METHODS: eEF1A2 levels were detected in 62 HCC tissue samples and paired pericarcinomatous specimens, and the human HCC cell lines SK-HEP-1, HepG2 and BEF-7402, by real-time PCR and immunohistochemistry. Experimental groups included eEF1A2 silencing in BEL-7402 cells with lentivirus eEF1A2-shRNA (KD group) and eEF1A2 overexpression in SK-HEP-1 cells with eEF1A2 plasmid (OE group). Non-transfected cells (control group) and lentivirus-based empty vector transfected cells (NC group) were considered control groups. Cell proliferation (MTT and colony formation assays), apoptosis (Annexin V-APC assay), cell cycle (DNA ploidy assay), and migration and invasion (Transwell assays) were assessed. Protein levels of PI3K/Akt/NF-&#x003ba;B signaling effectors were evaluated by Western blot.RESULTS: eEF1A2 mRNA and protein levels were significantly higher in HCC cancer tissue samples than in paired pericarcinomatous and normal specimens. SK-HEP-1 cells showed lower eEF1A2 mRNA levels; HepG2 and BEL-7402 cells showed higher eEF1A2 mRNA levels, with BEL-7402 cells displaying the highest amount. Efficient eEF1A2 silencing resulted in reduced cell proliferation, migration and invasion, increased apoptosis, and induced cell cycle arrest. The PI3K/Akt/NF-&#x003ba;B signaling pathway was notably inhibited. Inversely, eEF1A2 overexpression resulted in promoted cell proliferation, migration and invasion.CONCLUSION: eEF1A2, highly expressed in HCC, is a potential oncogene. Its silencing significantly decreases HCC tumorigenesis, likely by inhibiting PI3K/Akt/NF-&#x003ba;B signaling.

shRNA-interfering LSD1 inhibits proliferation and invasion of gastric cancer cells via VEGF-C/PI3K/AKT signaling pathway

BACKGROUND Histone Lysine Specific Demethylase 1(LSD1)is the first histone demethylase to be discovered,which regulates various biological functions by making lysine of histone H3K4,H3K9 and non-histone substrates demethylated.Abnormal regulation of LSD1 is closely related to the occurrence and development of gastric cancer.The change of LSD1 expression level plays an important role in the proliferation and metastasis of gastric cancer cells.The study of its function and mechanism may provide a theoretical basis for early diagnosis and targeted therapy of gastric cancer.AIM To investigate the effect of downregulation of lysine-specific demethylase 1(LSD1)expression on proliferation and invasion of gastric cancer cells and the possible regulatory mechanisms of the VEGF-C/PI3K/AKT signaling pathway.METHODS The LSD1-specific short hairpin RNA(shRNA)interference plasmid was transiently transfected,and expression of LSD1 was downregulated.The cell proliferation ability of LSD1 was observed by CCK-8 assay after downregulating expression of LSD1.Transwell invasion assay was used to observe the change of cell invasion ability after downregulating expression of LSD1.Expression of phosphorylated phosphoinositide 3-kinase(p-PI3K),PI3K,p-AKT,AKT,vascular endothelial growth factor receptor(VEGFR)-3,matrix metalloproteinase(MMP)-2 and MMP-9 in each group was detected by Western blotting.RESULTS The cell proliferation ability of transiently transfected LSD1-shRNA interference plasmid group was significantly lower than that of the control group(P<0.05).Transwell invasion assay showed that the number of cells across the membrane of the LSD1-shRNA transfection group(238.451±5.216)was significantly lower than that of the control group(49.268±6.984)(P<0.01).Western blotting showed that expression level of VEGF-C,p-PI3K,PI3K,p-AKT,AKT,VEGFR-3,MMP-2 and MMP-9 in the LSD1-shRNA group was significantly lower than that in the control group(P<0.05).CONCLUSION Downregulation of LSD1 expression inhibits metastatic potential of gastric cancer cells,and VEGF-C-mediated activation of PI3K/AKT signaling pathway,which may be an important mechanism for inhibiting lymph node metastasis in gastric cancer cells.

Scoparone inhibits pancreatic cancer through PI3K/Akt signaling pathway

BACKGROUND Pancreatic cancer is a highly malignant tumor of the gastrointestinal system whose emerging resistance to chemotherapy has necessitated the development of novel antitumor treatments.Scoparone,a traditional Chinese medicine monomer with a wide range of pharmacological properties,has attracted considerable attention for its antitumor activity.AIM To explore the potential antitumor effect of scoparone on pancreatic cancer and the possible molecular mechanism of action.METHODS The target genes of scoparone were determined using both the bioinformatics and multiplatform analyses.The effect of scoparone on pancreatic cancer cell proliferation,migration,invasion,cell cycle,and apoptosis was detected in vitro.The expression of hub genes was tested using quantitative reverse transcription polymerase chain reaction(qRT-PCR),and the molecular mechanism was analyzed using Western blot.The in vivo effect of scoparone on pancreatic cancer cell proliferation was detected using a xenograft tumor model in nude mice as well as immunohistochemistry.RESULTS The hub genes involved in the suppression of pancreatic cancer by scoparone were obtained by network bioinformatics analyses using publicly available databases and platforms,including SwissTargetPrediction,STITCH,GeneCards,CTD,STRING,WebGestalt,Cytoscape,and Gepia;AKT1 was confirmed using qRT-PCR to be the hub gene.Cell Counting Kit-8 assay revealed that the viability of Capan-2 and SW1990 cells was significantly reduced by scoparone treatment exhibiting IC50 values of 225.2μmol/L and 209.1μmol/L,respectively.Wound healing and transwell assays showed that scoparone inhibited the migration and invasion of pancreatic cancer cells.Additionally,flow cytometry confirmed that scoparone caused cell cycle arrest and induced apoptosis.Scoparone also increased the expression levels of Bax and cleaved caspase-3,decreased the levels of MMP9 and Bcl-2,and suppressed the phosphorylation of Akt without affecting total PI3K and Akt.Moreover,compared with the control group,xenograft tumors,in the 200μmol/L scoparone treatment group,were smaller in volume and lighter in weight,and the percentages of Ki65-and PCNA-positive cells were decreased.CONCLUSION Our findings indicate that scoparone inhibits pancreatic cancer cell proliferation in vitro and in vivo,inhibits migration and invasion,and induces cycle arrest and apoptosis in vitro through the PI3K/Akt signaling pathway.

化瘀祛痰方通过抑制PI3K/AKT/mTOR信号通路减轻油酸和棕榈酸引起的HepG2细胞脂质沉积

目的研究化瘀祛痰方对油酸和棕榈酸诱导HepG2细胞脂质沉积的影响及其作用机制。方法体外培养HepG2细胞,随机分为5组:正常对照组、模型组[培养液中加入终浓度为1 mmol/L的油酸和棕榈酸混合物(摩尔比为2∶1)]、20μmol/L LY294002处理组、化瘀祛痰方处理组、化瘀祛痰方联合20μmol/L LY294002处理组。采用油红O染色和细胞内甘油三酯(TG)含量测定法检测各组HepG2细胞脂质沉积情况;采用免疫荧光细胞化学染色法观察各组微管相关蛋白1轻链3(LC3)的表达;采用Western blot法检测各组磷酸化蛋白激酶B(p-AKT)、磷酸化的哺乳动物雷帕霉素靶蛋白(p-mTOR)、LC3B、胆固醇调节元件结合蛋白1c(SREBP-1c)的水平。结果与正常对照组相比,模型组细胞内脂滴形成增多、TG含量显著升高,SREBP-1c蛋白水平显著升高;模型组、化瘀祛痰方组、化瘀祛痰方联合LY294002组LC3B呈不同程度的阳性表达。与模型组相比,LY294002组、化瘀祛痰方组、化瘀祛痰方联合LY294002组p-AKT、p-mTOR蛋白水平显著降低;化瘀祛痰方组、化瘀祛痰方联合LY294002组的细胞内脂滴形成减少、TG含量显著减低,SREBP-1c蛋白水平显著降低、LC3B蛋白水平显著升高。结论化瘀祛痰方抑制PI3K/AKT/mTOR信号通路上调细胞自噬水平,减轻油酸和棕榈酸诱导的Hep G2细胞脂质沉积。