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.

Liqi Huoxue dripping pill protects against myocardial ischemia-reperfusion injury via the PI3K/Akt/GSK-3β signaling pathway in rats

Background:Liqi Huoxue dripping pill(LQHXDP),a traditional Chinese drug for coronary heart disease,has a protective effect on the heart of rats with myocardial ischemia-reperfusion injury(MIRI)in previous studies;however,its mechanism of action remains unclear.The purpose of this study was to investigate the protective mechanism of LQHXDP on MIRI in rats and its relationship with the PI3K/Akt signaling pathway.Methods:In this study,Sprague-Dawley rats were pre-infused with LQHXDP(175 mg/kg/d)for 10 days.PI3K inhibitor LY294002(0.3 mg/kg)was intravenously injected 15 minutes before ischemia.The rat model of MIRI was established by ligating the left anterior descending coronary artery.Subsequently,cardiac hemodynamics,serum myocardial injury markers,inflammatory factors,myocardial infarct size,antioxidant indexes,myocardial histopathology,and phosphorylation levels of key proteins of PI3K/Akt signaling pathway were assessed in rats.Results:LQHXDP was found to improve cardiac hemodynamic indexes,reduce serum creatine kinase MB isoenzyme activity and cardiac troponin and heart-type fatty acid binding protein levels,lower serum interleukin-1 beta,interleukin-6 and tumour necrosis factorαlevels,reduce the myocardial infarct size and enhance the antioxidant capacity of myocardial tissue in MIRI rats.Pathological analysis revealed that LQHXDP attenuated the extent of myocardial injury and protected mitochondria from damage in MIRI rats.Immunoblot analysis revealed that LQHXDP increased the expression levels of p-Akt and p-GSK-3βin MIRI rat cardiomyocytes.PI3K inhibitor LY294002 could impair these effects of LQHXDP.Conclusion:LQHXDP attenuated myocardial injury,attenuated oxidative stress injury and reduced inflammatory response in MIRI rats,and its protective effects were mediated by activating of PI3K/Akt/GSK-3βsignaling pathway.

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.

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.

Zuo Gui Wan Promotes Osteogenesis via PI3K/AKT Signaling Pathway:Network Pharmacology Analysis and Experimental Validation

Objective Osteogenesis is vitally important for bone defect repair,and Zuo Gui Wan(ZGW)is a classic prescription in traditional Chinese medicine(TCM)for strengthening bones.However,the specific mechanism by which ZGW regulates osteogenesis is still unclear.The current study is based on a network pharmacology analysis to explore the potential mechanism of ZGW in promoting osteogenesis.Methods A network pharmacology analysis followed by experimental validation was applied to explore the potential mechanisms of ZGW in promoting the osteogenesis of bone marrow mesenchymal stem cells(BMSCs).Results In total,487 no-repeat targets corresponding to the bioactive components of ZGW were screened,and 175 target genes in the intersection of ZGW and osteogenesis were obtained.And 28 core target genes were then obtained from a PPI network analysis.A GO functional enrichment analysis showed that the relevant biological processes mainly involve the cellular response to chemical stress,metal ions,and lipopolysaccharide.Additionally,KEGG pathway enrichment analysis revealed that multiple signaling pathways,including the phosphatidylinositol-3-kinase/protein kinase B(PI3K/AKT)signaling pathway,were associated with ZGW-promoted osteogensis.Further experimental validation showed that ZGW could increase alkaline phosphatase(ALP)activity as well as the mRNA and protein levels of ALP,osteocalcin(OCN),and runt related transcription factor 2(Runx 2).What’s more,Western blot analysis results showed that ZGW significantly increased the protein levels of p-PI3K and p-AKT,and the increases of these protein levels significantly receded after the addition of the PI3K inhibitor LY294002.Finally,the upregulated osteogenic-related indicators were also suppressed by the addition of LY294002.Conclusion ZGW promotes the osteogenesis of BMSCs via PI3K/AKT signaling 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.

XB130 inhibits healing of diabetic skin ulcers through the PI3K/Akt signalling pathway

BACKGROUND Diabetic skin ulcers,a significant global healthcare burden,are mainly caused by the inhibition of cell proliferation and impaired angiogenesis.XB130 is an adaptor protein that regulates cell proliferation and migration.However,the role of XB130 in the development of diabetic skin ulcers remains unclear.AIM To investigate whether XB130 can regulate the inhibition of proliferation and vascular damage induced by high glucose.Additionally,we aim to determine whether XB130 is involved in the healing process of diabetic skin ulcers,along with its molecular mechanisms.METHODS We conducted RNA-sequencing analysis to identify the key genes involved in diabetic skin ulcers.We investigated the effects of XB130 on wound healing using histological analyses.In addition,we used reverse transcription-quantitative polymerase chain reaction,Western blot,terminal deoxynucleotidyl transferasemediated dUTP nick end labeling staining,immunofluorescence,wound healing,and tubule formation experiments to investigate their effects on cellular processes in human umbilical vein endothelial cells(HUVECs)stimulated with high glucose.Finally,we performed functional analysis to elucidate the molecular mechanisms underlying diabetic skin ulcers.RESULTS RNA-sequencing analysis showed that the expression of XB130 was up-regulated in the tissues of diabetic skin ulcers.Knockdown of XB130 promoted the healing of skin wounds in mice,leading to an accelerated wound healing process and shortened wound healing time.At the cellular level,knockdown of XB130 alleviated high glucose-induced inhibition of cell proliferation and angiogenic impairment in HUVECs.Inhibition of the PI3K/Akt pathway removed the proliferative effects and endothelial protection mediated by XB130.CONCLUSION The findings of this study indicated that the expression of XB130 is up-regulated in high glucose-stimulated diabetic skin ulcers and HUVECs.Knockdown of XB130 promotes cell proliferation and angiogenesis via the PI3K/Akt signalling pathway,which accelerates the healing of diabetic skin ulcers.

Anti-diabetic potential of apigenin,luteolin,and baicalein via partially activating PI3K/Akt/GLUT-4 signaling pathways in insulin-resistant HepG2 cells

Dietary flavonoids are abundant in natural plants and possess multiple pharmacological and nutritional activities.In this study,apigenin,luteolin,and baicalein were chosen to evaluate their anti-diabetic effect in high-glucose and dexamethasone induced insulin-resistant(IR)HepG2 cells.All flavonoids improves the glucose consumption and glycogen synthesis abilities in IR-HepG2 cells via activating glucose transporter protein 4(GLUT4)and phosphor-glycogen synthase kinase(GSK-3β).These fl avonoids signifi cantly inhibited the production of reactive oxygen species(ROS)and advanced glycation end-products(AGEs),which were closely related to the suppression of the phosphorylation form of NF-κB and P65.The expression levels of insulin receptor substrate-1(IRS-1),insulin receptor substrate-2(IRS-2)and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)pathway in IR-HepG2 cells were all partially activated by the fl avonoids,with variable effects.Furthermore,the intracellular metabolic conditions of the fl avonoids were also evaluated.

Simiao Wan alleviates obesity-associated insulin resistance via PKCε/IRS-1/PI3K/Akt signaling pathway based on network pharmacology analysis and experimental validation

Background:The purpose of the study was to investigatethe active ingredients and potential biochemicalmechanisms of Simiao Wan(SMW)in obesity-associated insulin resistance.Methods:An integrated network pharmacology method to screen the active compoundsand candidate targets,construct the protein-protein-interaction network,and ingredients-targets-pathways network was constructed for topological analysis to identify core targets and main ingredients.To find the possible signaling pathways,enrichment analysis was performed.Further,a model of insulin resistance in HL-7702 cells was established to verify the impact of SMW and the regulatory processes.Results:An overall of 63 active components and 151 candidate targets were obtained,in which flavonoids were the main ingredients.Enrichment analysis indicated that the PI3K-Akt signaling pathway was the potential pathway regulated by SMW in obesity-associated insulin resistance treatment.The result showed that SMW could significantly ameliorate insulin sensitivity,increase glucose synthesis and glucose utilization and reduce intracellular lipids accumulation in hepatocytes.Also,SMW inhibited diacylglycerols accumulation-induced PKCεactivity and decreased its translocation to the membrane.Conclusion:SMW ameliorated obesity-associated insulin resistance through PKCε/IRS-1/PI3K/Akt signaling axis in hepatocytes,providing a new strategy for metabolic disease treatment.

The role and research progress of PI3K/AKT signaling pathway in non-traumatic osteonecrosis of the femoral head

Non-traumatic osteonecrosis of the femoral head(NONFH)is one of the most common orthopedic diseases,influenced by multiple signaling pathways and inflammatory factors.The PI3K/AKT signaling pathway is closely related to various biological processes such as apoptosis,autophagy,and metabolism in cells.Increasing evidence suggests that it plays an important role in the development of femoral head necrosis.This paper aims to explore the mechanism of the PI3K/AKT signaling pathway in the pathogenesis of NONFH by analyzing its regulation of lipid metabolism,cell apoptosis and autophagy,and intravascular coagulation.This study provides new insights for the research of NONFH.

Downregulation of LncRNAH19 and MiR-675 Promotes Migration and Invasion of Human Hepatocellular Carcinoma Cells through AKT/GSK-3β/Cdc25A Signaling Pathway

Summary： LncRNAH19 has been implicated as having both oncogenic and tumor suppression properties in cancer. LncRNAH19 transcripts also serve as a precursor for miR-675. However, it is unknown whether LncRNAH19 and miR-675 are involved in the migration and invasion of hepatocellular carcinoma （HCC） cells. The purpose of this study was to investigate the effect and mechanism of LncRNAH19 and miR-675 on migration and invasion of HCC cells. The migration and invasion of HCC cells were measured by Transwell migration and invasion assays after transfection of HCC cells with miR-675 inhibitors and LncRNAH19siRNA. The levels of LncRNAH19 and miR-675 were detected by quantitative reverse transcriptase real-time polymerase chain reaction （qRT-PCR）, and the protein expression of AKT, GSK-3[3 and Cdc25A by Western blotting analysis. The expression levels of LncRNAHI9 and miR-675 were higher in MHCC-97H cells than in L02, Huh-7 and HepG2 cells. Transwell migration assay revealed that the miR-675 inhibitor and LncRNAH19siRNA could significantly increase the migration of HCC cells （P〈0.01） as compared with the control group. Transwell invasion assay demonstrated that the miR-675 inhibitor and LncRNAH19siRNA could significantly increase the invasion of HCC cells （P〈0.01） as compared with the control group. Western blotting analy- sis showed that the expression levels of AKT and Cdc25A were significantly increased （P〈0.05）, and the expression level of GSK-313 was significantly decreased （P〈0.05） after treatment with miR-675 inhibitors and LncRNAH19siRNA as compared with the control group. These findings suggested that inhibition of LncRNAH 19 and miR-675 expression can promote migration and invasion of HCC cells via AKT/GSK-3[3/Cdc25A signaling pathway.

Antitumor activity of miR-188-3p in gastric cancer is achieved by targeting CBL expression and inactivating the AKT/mTOR signaling

BACKGROUND Altered miR-188-3p expression has been observed in various human cancers.AIM To investigate the miR-188-3p expression,its roles,and underlying molecular events in gastric cancer.METHODS Fifty gastric cancer and paired normal tissues were collected to analyze miR-188-3p and CBL expression.Normal and gastric cancer cells were used to manipulate miR-188-3p and CBL expression through different assays.The relationship between miR-188-3p and CBL was predicted bioinformatically and confirmed using a luciferase gene reporter assay.A Kaplan-Meier analysis was used to associate miR-188-3p or CBL expression with patient survival.A nude mouse tumor cell xenograft assay was used to confirm the in vitro data.RESULTS MiR-188-3p was found to be lower in the plasma of gastric cancer patients,tissues,and cell lines compared to their healthy counterparts.It was associated with overall survival of gastric cancer patients(P<0.001),tumor differentiation(P<0.001),lymph node metastasis(P=0.033),tumor node metastasis stage(I/II vs III/IV,P=0.024),and American Joint Committee on Cancer stage(I/II vs III/IV,P=0.03).Transfection with miR-188-3p mimics reduced tumor cell growth and invasion while inducing apoptosis and autophagy.CBL was identified as a direct target of miR-188-3p,with its expression antagonizing the effects of miR-188-3p on gastric cancer(GC)cell proliferation by inducing tumor cell apoptosis and autophagy through the inactivation of the Akt/mTOR signaling pathway.The in vivo data confirmed antitumor activity via CBL downregulation in gastric cancer.CONCLUSION The current data provides ex vivo,in vitro,and in vivo evidence that miR-188-3p acts as a tumor suppressor gene or possesses antitumor activity in GC.

Expression and correlation of pyroptosis-related markers and PI3K/AKT pathway in endometriosis

Objective:The expression of pyroptosis related factors GSDMD,Caspase-1,NLRP3,IL-1β,IL-18 and PI3K/AKT signaling pathways in ovarian endometriosis was investigated and their correlations analyzed.Methods:A total of 50 patients with endometriosis who underwent ovarian cystectomy in the Department of Gynecology,the First Affiliated Hospital of Bengbu Medical College from January 2022 to January 2023 were enrolled as endometriosis group.In addition,55 patients with normal endometrial tissue who underwent hysteroscopic surgery in the hospital during the same period were selected as the control group,and patients with endometriosis were excluded during the operation.RT-qPCR,Western Blot was used to detect the expression of pyroptosis-related factor and PI3K/AKT signaling pathway mRAN,protein in the above tissues,and the correlation between the expression of the two was analyzed by Pearson correlation test.Results:The expression of pyroptosis-related factors and mRAN of PI3K/AKT signaling pathway in ectopic ovarian cyst tissues was significantly higher than that in the control group,and the difference was statistically significant(P<0.05).Pearson correlation analysis showed that pyroptosis-related factors in ectopic ovarian cysts were positively correlated with the mRNA expression levels of PI3K/AKT signaling pathway(P<0.05).Conclusion:The pyroptosis correlation factors GSDMD,Caspase-1,NLRP3,IL-1β,IL-18 and PI3K/AKT signaling pathways are highly expressed in ovarian endometriosis,and the pyroptosis-related factors are positively correlated with the expression of PI3K/AKT signaling pathway,suggesting that the regulation of endometriosis by activating the PI3K/AKT signaling pathway is likely to be achieved by activating the PI3K/AKT 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.

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.

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.

Panax notogiseng saponin inhibits ischemia-induced apoptosis by activating PI3K/Akt signal pathway in cardiomyocytes

The panax notoginseng saponin(PNS) had been clinically used for the treatment of cardiovascular diseases and stroke in China.It had been demonstrated that PNS could protect cardiomyocytes from injury induced by ischemi- a,but the underlying molecular mechanisms of this protective effect were still unclear.This study was aimed to investigate the protective effect and molecular mechanisms of PNS on apoptosis in H9c2 cells in vitro and rat myocardial ischemia injury model in vivo.Annexin-V/PI assay shew that PNS could protect H9c2 cells from apoptosis induced by serum, glucose and oxygen deprivation(SGOD) in a dose-dependent manner.However,the anti-apoptotic effect of PNS was reversed by LY294002,a specific PI3K inhibitor.This antiapoptotic effect of PNS was confirmed by JC-1,a specific probe of mitochondrial membrane potential staining.PNS could significantly increase phos-Akt in H9c2 cells by Western blot assays and its effect could be inhibited by LY294002.Furthermore,PNS could improve ischemic-induced left ventricular function as reflected by EF,LVDd and LVDs.PNS could also inhibited cellular apoptosis in myocardial tissues in ischemic rats by TUNEL assay.PNS administration also increased the expression of phos-Akt in rat ischemic myocardial tissues.These results suggested that PNS could protect myocardial cells from apoptosis induced by ischemia in vitro model and in vivo model through activating-PI3K/Akt signal pathway which may be meaningful for further understanding the molecular mechanisms of cardiac protection of PNS.And the results might be useful in treatment of myocardial ischemia in future.

Ezetimibe Protects Endothelial Cells against Oxidative Stress through Akt/GSK-3β Pathway

Ezetimibe was reported to pharmacologically defend against oxidative stress. This study was designed to investigate whether ezetimibe can protect against the oxidative stress induced by oxidized low-density lipoprotein （oxLDL） in vitro and the underlying mechanism. Human umbilical vein endothelial cells （HUVECs） were pretreated with ezetimibe and then exposed to oxLDL for 24 h. TUNEL assay and detection for the protein levels of cleaved caspase-3, Bcl-xl and Bcl-2 were employed to assess the oxLDL-induced endothelial apoptosis. Intracellular reactive oxygen species （ROS） generation was evaluated by measuring dichlorofluorescein （DCF） fluorescence. The activities of endothelial antioxidant enzymes [superoxide dismutase （SOD） and catalase] were tested via an enzymatic assay. The mitochondrial membrane potential （MMP） was monitored by flow cytometry using JC-I staining. Phosphorylation levels of glycogen synthase kinase-3β （p-GSK-3β） and Akt （p-Akt）, as well as total GSK-3β and Akt were determined by Western blotting. The results showed that ezetimibe treatment inhibited HUVECs apoptosis, intracellular ROS production, and enhanced antioxidant enzyme activities elicited by oxLDL. HUVECs exposed to oxLDL alone had reduced mitochondrial function, while ezetimibe pre-intervention could significantly rescue the MMP. Furthermore, the protein levels of p-GSK-3β and p-Akt in ezetimibe-pretreated HUVECs were markedly increased as compared with those in oxLDL-induced HUVECs. However, no significant effect on total GSK- 3β and Akt was found in ezetimibe-pretreated HUVECs. Taken together, it was concluded that ezetimibe protects against oxLDL-induced oxidative stress through restoring the MMP, which may be mediated by Akt-dependent GSK-3β phosphorylation.