AIM: To investigate the molecular mechanism for regulation of cholesterol metabolism by hepatitis C virus(HCV) core protein in Hep G2 cells.METHODS: HCV genotype 1b core protein was cloned and expressed in Hep G2 cell...AIM: To investigate the molecular mechanism for regulation of cholesterol metabolism by hepatitis C virus(HCV) core protein in Hep G2 cells.METHODS: HCV genotype 1b core protein was cloned and expressed in Hep G2 cells. The cholesterol content was determined after transfection. The expression of sterol regulatory element binding protein 2(SREBP2) and the rate-limiting enzyme in cholesterol synthesis(HMGCR) was measured by quantitative real-time PCR and immunoblotting after transfection. The effects of core protein on the SREBP2 promoter and 3'-untranslated region were analyzed by luciferase assay. We used different target predictive algorithms, micro RNA(mi RNA) mimics/inhibitors, and site-directed mutation to identify a putative target of a particular mi RNA.RESULTS: HCV core protein expression in Hep G2 cells increased the total intracellular cholesterol level(4.05 ± 0.17 vs 6.47 ± 0.68, P = 0.001), and this increase corresponded to an increase in SREBP2 and HMGCR m RNA levels(P = 0.009 and 0.037, respectively) and protein expression. The molecular mechanism studyrevealed that the HCV core protein increased the expression of SREBP2 by enhancing its promoter activity(P = 0.004). In addition, mi R-185-5p expression was tightly regulated by the HCV core protein(P = 0.041). Moreover, overexpression of mi R-185-5p repressed the SREBP2 m RNA level(P = 0.022) and protein expression. In contrast, inhibition of mi R-185-5p caused upregulation of SREBP2 protein expression. mi R-185-5p was involved in the regulation of SREBP2 expression by HCV core protein. CONCLUSION: HCV core protein disturbs the cholesterol homeostasis in Hep G2 cells via the SREBP2 pathway; mi R-185-5p is involved in the regulation of SREBP2 by the core protein.展开更多
BACKGROUND Diabetic kidney disease(DKD),characterized by increased urinary microalbumin levels and decreased renal function,is the primary cause of end-stage renal di-sease.Its pathological mechanisms are complicated ...BACKGROUND Diabetic kidney disease(DKD),characterized by increased urinary microalbumin levels and decreased renal function,is the primary cause of end-stage renal di-sease.Its pathological mechanisms are complicated and multifactorial;Therefore,sensitive and specific biomarkers are needed.Urinary exosome originate from diverse renal cells in nephron segments and partially mirror the pathological changes in the kidney.The microRNAs(miRNAs)in urinary exosome are remark-ably stable and highly tissue-specific for the kidney.METHODS Type 2 diabetic mellitus(T2DM)patients were recruited from the Second Hospital of Hebei Medical University and were divided into two groups:DM,diabetic pa-tients without albuminuria[urinary albumin to creatinine ratio(UACR)<30 mg/g]and DKD,diabetic patients with albuminuria(UACR≥30 mg/g).Healthy subjects were the normal control(NC)group.Urinary exosomal miR-145-5p,miR-27a-3p,and miR-29c-3p,were detected using real-time quantitative polymerase chain reaction.The correlation between exosomal miRNAs and the clinical in-dexes was evaluated.The diagnostic values of exosomal miR-145-5p and miR-27a-3p in DKD were determined using receiver operating characteristic(ROC)analysis.Biological functions of miR-145-5p were investigated by performing RESULTS Urinary exosomal expression of miR-145-5p and miR-27a-3p was more upregulated in the DKD group than in the DM group(miR-145-5p:4.54±1.45 vs 1.95±0.93,P<0.001;miR-27a-3p:2.33±0.79 vs 1.71±0.76,P<0.05)and the NC group(miR-145-5p:4.54±1.45 vs 1.55±0.83,P<0.001;miR-27a-3p:2.33±0.79 vs 1.10±0.51,P<0.001).The exosomal miR-145-5p and miR-27a-3p positively correlated with albuminuria and serum creatinine and negatively correlated with the estimated glomerular filtration rate.miR-27a-3p was also closely related to blood glucose,gly-cosylated hemoglobin A1c,and low-density lipoprotein cholesterol.ROC analysis revealed that miR-145-5p had a better area under the curve of 0.88[95%confidence interval(CI):0.784-0.985,P<0.0001]in diagnosing DKD than miR-27a-3p with 0.71(95%CI:0.547-0.871,P=0.0239).Bioinformatics analysis revealed that the target genes of miR-145-5p were located in the actin filament,cytoskeleton,and extracellular exosome and were involved in the pathological processes of DKD,including apoptosis,inflammation,and fibrosis.CONCLUSION Urinary exosomal miR-145-5p and miR-27a-3p may serve as novel noninvasive diagnostic biomarkers or promising therapeutic targets for DKD.展开更多
BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patie...BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patients with diabetes are unknown.In this study,we investigated the regulation of BMSC-exo on hyperglycemia-induced neuroinflammation.AIM To study the mechanism of BMSC-exo on nerve function damage after diabetes complicated with cerebral hemorrhage.METHODS BMSC-exo were isolated from mouse BMSC media.This was followed by transfection with microRNA-129-5p(miR-129-5p).BMSC-exo or miR-129-5poverexpressing BMSC-exo were intravitreally injected into a diabetes mouse model with ICH for in vivo analyses and were cocultured with high glucoseaffected BV2 cells for in vitro analyses.The dual luciferase test and RNA immunoprecipitation test verified the targeted binding relationship between miR-129-5p and high-mobility group box 1(HMGB1).Quantitative polymerase chain reaction,western blotting,and enzyme-linked immunosorbent assay were conducted to assess the levels of some inflammation factors,such as HMGB1,interleukin 6,interleukin 1β,toll-like receptor 4,and tumor necrosis factorα.Brain water content,neural function deficit score,and Evans blue were used to measure the neural function of mice.RESULTS Our findings indicated that BMSC-exo can promote neuroinflammation and functional recovery.MicroRNA chip analysis of BMSC-exo identified miR-129-5p as the specific microRNA with a protective role in neuroinflammation.Overexpression of miR-129-5p in BMSC-exo reduced the inflammatory response and neurological impairment in comorbid diabetes and ICH cases.Furthermore,we found that miR-129-5p had a targeted binding relationship with HMGB1 mRNA.CONCLUSION We demonstrated that BMSC-exo can reduce the inflammatory response after ICH with diabetes,thereby improving the neurological function of the brain.展开更多
基金Supported by Medical Specialty Development Projects of Beijing Municipal Administration of Hospitals,No.ZYLX201402Ministry of Education of The People’s Republic of China,No.20121107110012+1 种基金Beijing Municipal Commission of Education,No.11320016Collaborative Innovation Center of Infectious Diseases and Beijing Key Laboratory of Emerging Infectious Diseases,Beijing,China
文摘AIM: To investigate the molecular mechanism for regulation of cholesterol metabolism by hepatitis C virus(HCV) core protein in Hep G2 cells.METHODS: HCV genotype 1b core protein was cloned and expressed in Hep G2 cells. The cholesterol content was determined after transfection. The expression of sterol regulatory element binding protein 2(SREBP2) and the rate-limiting enzyme in cholesterol synthesis(HMGCR) was measured by quantitative real-time PCR and immunoblotting after transfection. The effects of core protein on the SREBP2 promoter and 3'-untranslated region were analyzed by luciferase assay. We used different target predictive algorithms, micro RNA(mi RNA) mimics/inhibitors, and site-directed mutation to identify a putative target of a particular mi RNA.RESULTS: HCV core protein expression in Hep G2 cells increased the total intracellular cholesterol level(4.05 ± 0.17 vs 6.47 ± 0.68, P = 0.001), and this increase corresponded to an increase in SREBP2 and HMGCR m RNA levels(P = 0.009 and 0.037, respectively) and protein expression. The molecular mechanism studyrevealed that the HCV core protein increased the expression of SREBP2 by enhancing its promoter activity(P = 0.004). In addition, mi R-185-5p expression was tightly regulated by the HCV core protein(P = 0.041). Moreover, overexpression of mi R-185-5p repressed the SREBP2 m RNA level(P = 0.022) and protein expression. In contrast, inhibition of mi R-185-5p caused upregulation of SREBP2 protein expression. mi R-185-5p was involved in the regulation of SREBP2 expression by HCV core protein. CONCLUSION: HCV core protein disturbs the cholesterol homeostasis in Hep G2 cells via the SREBP2 pathway; mi R-185-5p is involved in the regulation of SREBP2 by the core protein.
基金Supported by the Nature Science Foundation of Hebei Province,No.H2023104011.
文摘BACKGROUND Diabetic kidney disease(DKD),characterized by increased urinary microalbumin levels and decreased renal function,is the primary cause of end-stage renal di-sease.Its pathological mechanisms are complicated and multifactorial;Therefore,sensitive and specific biomarkers are needed.Urinary exosome originate from diverse renal cells in nephron segments and partially mirror the pathological changes in the kidney.The microRNAs(miRNAs)in urinary exosome are remark-ably stable and highly tissue-specific for the kidney.METHODS Type 2 diabetic mellitus(T2DM)patients were recruited from the Second Hospital of Hebei Medical University and were divided into two groups:DM,diabetic pa-tients without albuminuria[urinary albumin to creatinine ratio(UACR)<30 mg/g]and DKD,diabetic patients with albuminuria(UACR≥30 mg/g).Healthy subjects were the normal control(NC)group.Urinary exosomal miR-145-5p,miR-27a-3p,and miR-29c-3p,were detected using real-time quantitative polymerase chain reaction.The correlation between exosomal miRNAs and the clinical in-dexes was evaluated.The diagnostic values of exosomal miR-145-5p and miR-27a-3p in DKD were determined using receiver operating characteristic(ROC)analysis.Biological functions of miR-145-5p were investigated by performing RESULTS Urinary exosomal expression of miR-145-5p and miR-27a-3p was more upregulated in the DKD group than in the DM group(miR-145-5p:4.54±1.45 vs 1.95±0.93,P<0.001;miR-27a-3p:2.33±0.79 vs 1.71±0.76,P<0.05)and the NC group(miR-145-5p:4.54±1.45 vs 1.55±0.83,P<0.001;miR-27a-3p:2.33±0.79 vs 1.10±0.51,P<0.001).The exosomal miR-145-5p and miR-27a-3p positively correlated with albuminuria and serum creatinine and negatively correlated with the estimated glomerular filtration rate.miR-27a-3p was also closely related to blood glucose,gly-cosylated hemoglobin A1c,and low-density lipoprotein cholesterol.ROC analysis revealed that miR-145-5p had a better area under the curve of 0.88[95%confidence interval(CI):0.784-0.985,P<0.0001]in diagnosing DKD than miR-27a-3p with 0.71(95%CI:0.547-0.871,P=0.0239).Bioinformatics analysis revealed that the target genes of miR-145-5p were located in the actin filament,cytoskeleton,and extracellular exosome and were involved in the pathological processes of DKD,including apoptosis,inflammation,and fibrosis.CONCLUSION Urinary exosomal miR-145-5p and miR-27a-3p may serve as novel noninvasive diagnostic biomarkers or promising therapeutic targets for DKD.
基金Supported by the National Natural Science Foundation of China,No.81900743Heilongjiang Province Outstanding Young Medical Talents Training Grant Project,China,No.HYD2020YQ0007.
文摘BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patients with diabetes are unknown.In this study,we investigated the regulation of BMSC-exo on hyperglycemia-induced neuroinflammation.AIM To study the mechanism of BMSC-exo on nerve function damage after diabetes complicated with cerebral hemorrhage.METHODS BMSC-exo were isolated from mouse BMSC media.This was followed by transfection with microRNA-129-5p(miR-129-5p).BMSC-exo or miR-129-5poverexpressing BMSC-exo were intravitreally injected into a diabetes mouse model with ICH for in vivo analyses and were cocultured with high glucoseaffected BV2 cells for in vitro analyses.The dual luciferase test and RNA immunoprecipitation test verified the targeted binding relationship between miR-129-5p and high-mobility group box 1(HMGB1).Quantitative polymerase chain reaction,western blotting,and enzyme-linked immunosorbent assay were conducted to assess the levels of some inflammation factors,such as HMGB1,interleukin 6,interleukin 1β,toll-like receptor 4,and tumor necrosis factorα.Brain water content,neural function deficit score,and Evans blue were used to measure the neural function of mice.RESULTS Our findings indicated that BMSC-exo can promote neuroinflammation and functional recovery.MicroRNA chip analysis of BMSC-exo identified miR-129-5p as the specific microRNA with a protective role in neuroinflammation.Overexpression of miR-129-5p in BMSC-exo reduced the inflammatory response and neurological impairment in comorbid diabetes and ICH cases.Furthermore,we found that miR-129-5p had a targeted binding relationship with HMGB1 mRNA.CONCLUSION We demonstrated that BMSC-exo can reduce the inflammatory response after ICH with diabetes,thereby improving the neurological function of the brain.
