Objective To investigate the effect of type 2 dengue virus(DENV-2)infection on autophagy in human umbilical vein endothelial cells(HUVECs)and the mechanism mediating the inhibitory effect of baicalin against DENV-2 infection.Methods Cultured HUVECs with DENV-2 infection were treated with different concentrations of baicalin,and the changes in autophagy of the cells were detected using transmission electron microscopy.Lyso Tracker Red staining was used to examine pH changes in the lysosomes of the cells,and the expressions of ATG5,beclin-1,LC3,P62,STX17,SNAP29,VAMP8,and PI3K/AKT signaling pathway-related proteins were detected by Western blotting.DENV-2 replication in the cells were evaluated using RT-qPCR.The differentially expressed proteins in DENV-2-infected HUVECs were identified by proteomics screening.Results Treatment with baicalin did not significantly affect the viability of cultured HUVECs.Proteomic studies suggested that the PI3K-AKT pathway played an important role in mediating cell injury induced by DENV-2 infection.The results of RT-qPCR demonstrated that baicalin dose-dependently inhibited DENV-2 replication in HUVECs and produced the strongest inhibitory effect at the concentration of 50 μg/mL.Transmission electron microscopy,Lyso Tracker Red staining,RT-qPCR,and Western blotting all showed significant inhibitory effect of baicalin on DENV-2-induced autophagy in HUVECs.DENV-2 infection of HUVECs caused increased cellular expressions of LC3 and P62 proteins,which were significantly lowered by treatment with LY294002(a PI3K inhibitor).Conclusion Baicalin inhibits DENV-2 replication in HUVECs and suppresses DENV-2-induced cell autophagy by inhibiting the PI3K/AKT signaling pathway.

Objective To investigate the effect of type 2 dengue virus(DENV-2)infection on autophagy in human umbilical vein endothelial cells(HUVECs)and the mechanism mediating the inhibitory effect of baicalin against DENV-2 infection.Methods Cultured HUVECs with DENV-2 infection were treated with different concentrations of baicalin,and the changes in autophagy of the cells were detected using transmission electron microscopy.Lyso Tracker Red staining was used to examine pH changes in the lysosomes of the cells,and the expressions of ATG5,beclin-1,LC3,P62,STX17,SNAP29,VAMP8,and PI3K/AKT signaling pathway-related proteins were detected by Western blotting.DENV-2 replication in the cells were evaluated using RT-qPCR.The differentially expressed proteins in DENV-2-infected HUVECs were identified by proteomics screening.Results Treatment with baicalin did not significantly affect the viability of cultured HUVECs.Proteomic studies suggested that the PI3K-AKT pathway played an important role in mediating cell injury induced by DENV-2 infection.The results of RT-qPCR demonstrated that baicalin dose-dependently inhibited DENV-2 replication in HUVECs and produced the strongest inhibitory effect at the concentration of 50 μg/mL.Transmission electron microscopy,Lyso Tracker Red staining,RT-qPCR,and Western blotting all showed significant inhibitory effect of baicalin on DENV-2-induced autophagy in HUVECs.DENV-2 infection of HUVECs caused increased cellular expressions of LC3 and P62 proteins,which were significantly lowered by treatment with LY294002(a PI3K inhibitor).Conclusion Baicalin inhibits DENV-2 replication in HUVECs and suppresses DENV-2-induced cell autophagy by inhibiting the PI3K/AKT signaling pathway.

AIM:To study the expression of glucose transporters(GLUTs)and silent information regulators(SIRTs/sirtuins)in the liver of diabetic rats and human hepatocytes(LO2 cells)treated with high glucose.METHODS:(1)Twenty male SD rats were randomly divided into normal control(NC)group and diabetes mellitus(DM)group.The rats in DM group were given single intraperitoneal injection of streptozotocin(STZ,60 mg/kg)to establish the DM model,while the rats in NC group were intraperitoneally injected with equal volume of solvent once.Fasting blood glucose(FBG)and body mass were measured every 2 weeks.After 12 weeks of rearing,the blood and liver tissues of the rats were ob-tained after anesthesia with 1%sodium pentobarbitone,the biochemical indicators of blood were detected,and the liver in-dex was calculated.Hematoxylin-eosin(HE)staining and periodic acid-Schiff(PAS)staining were used to observe liver histopathological changes.Lipid accumulation in liver tissues was detected by oil red O staining.The expression levels of GLUTs and SIRTs family member proteins were detected in rat liver tissues.(2)The LO2 cells were treated with different concentrations of glucose for 48 h.The viability of the cells in each group was measured by CCK-8 assay,and Western blot was used to detected the protein expression levels of GLUTs and SIRTs in the cells.RESULTS:(1)Compared with NC group,the rats in DM group were depressed,lost weight,and the FBG and liver index were significantly increased(P＜0.05).The results of HE staining showed that the hepatic sinuses were dilatated and congested near the central vein in DM rats,and mild edema and scattered infiltration of inflammatory cells were found in liver cells.The results of oil red O staining showed the red fat droplets were diffusely scattered within liver cells in DM group.The results of PAS staining showed that there were numerous diffuse light purple circular droplets in the cytoplasm of the liver cells in the central ve-nous area of the DM rats.Western blot showed that the protein levels of GLUTs were higher and the protein levels of SIRTs were lower than those in NC group(P＜0.01).(2)The results of CCK-8 assay showed that the viability of LO2 cells was increased in 50 mmol/L glucose group(P＜0.01),without significant difference in 75,100 and 125 mmol/L glucose groups(all P＞0.05),and decreased in 150,175 and 200 mmol/L glucose groups(all P＜0.01).Later,150 mmol/L glu-cose was used as the high-glucose intervention condition.Western blot showed that the protein levels of GLUTs and SIRTs in LO2 cells under high glucose intervention were consistented with the results in animal experiments.CONCLUSION:High concentration of glucose can cause liver damage in SD rats and reduce the viability of human hepatocytes(LO2 cells).It can also increase the expression of GLUTs and decrease the expression of SIRTs in rat liver tissues and LO2 cells.Therefore,GLUTs and SIRTs family members may be the target proteins of diabetes-induced liver injury.

Background:Previous studies have proved that neutrophil gelatinase-associated lipocalin(NGAL)plays an important role in the progression of Crohn's disease(CD),and may serve as a potential biomarker for disease activity prediction,severity assessment,treatment response evaluation and prognosis monitoring.However,the diagnostic value of NGAL in perianal fistulizing Crohn's disease(pfCD)is still unclear.Aims:To investigate the serum level of NGAL and its diagnostic value in patients with active pfCD.Methods:A total of 66 patients diagnosed as pfCD from July 2021 to June 2023 at Longhua Hospital,Shanghai University of Traditional Chinese Medicine were enrolled,including 36 active pfCD patients and 30 inactive pfCD patients.The disease activity and perianal fistula activity were assessed by Crohn's disease activity index(CDAI)and perianal disease activity index(PDAI),respectively.Serum NGAL,fecal calprotectin(FC),C-reactive protein(CRP),erythrocyte sedimentation rate(ESR),as well as CDAI score and PDAI score were compared between the active and inactive pfCD patients,and the correlations of NGAL with the other parameters in active pfCD patients were analyzed.ROC curve was drawn to evaluate the values of serum NGAL,FC,CRP and ESR for diagnosis of active pfCD.Results:The serum NGAL,FC,CRP,ESR,CDAI score and PDAI score in active pfCD patients were significantly higher than those in inactive pfCD patients(all P＜0.001).NGAL was positively correlated with FC(r=0.64,P＜0.001),CRP(r=0.55,P＜0.001),ESR(r=0.53,P＜0.001),CDAI score(r=0.59,P＜0.001)and PDAI score(r=0.54,P＜0.001)in active pfCD patients.The optimal cut-off values of NGAL,FC,CRP and ESR were 220.5 μg/L,146.0 μg/g,7.9 mg/L and 23.5 mm/h,respectively,for the diagnosis of active pfCD,and the area under the curve were 0.922(95％CI:0.850-0.995),0.888(95％CI:0.806-0.970),0.853(95％CI:0.763-0.944)and 0.830(95％CI:0.731-0.930),respectively.Conclusions:Serum NGAL level is associated with the disease activity of pfCD,and can be used as a non-invasive biomarker for the clinical diagnosis of active pfCD.