Objective Obesity-induced kidney injury contributes to the development of diabetic nephropathy(DN).Here,we identified the functions of ubiquitin-specific peptidase 19(USP19)in HK-2 cells exposed to a combination of hi...Objective Obesity-induced kidney injury contributes to the development of diabetic nephropathy(DN).Here,we identified the functions of ubiquitin-specific peptidase 19(USP19)in HK-2 cells exposed to a combination of high glucose(HG)and free fatty acid(FFA)and determined its association with TGF-beta-activated kinase 1(TAK1).Methods HK-2 cells were exposed to a combination of HG and FFA.USP19 mRNA expression was detected by quantitative RT-PCR(qRT-PCR),and protein analysis was performed by immunoblotting(IB).Cell growth was assessed by Cell Counting Kit-8(CCK-8)viability and 5-ethynyl-2′-deoxyuridine(EdU)proliferation assays.Cell cycle distribution and apoptosis were detected by flow cytometry.The USP19/TAK1 interaction and ubiquitinated TAK1 levels were assayed by coimmunoprecipitation(Co-IP)assays and IB.Results In HG+FFA-challenged HK-2 cells,USP19 was highly expressed.USP19 knockdown attenuated HG+FFA-triggered growth inhibition and apoptosis promotion in HK-2 cells.Moreover,USP19 knockdown alleviated HG+FFA-mediated PTEN-induced putative kinase 1(PINK1)/Parkin pathway inactivation and increased mitochondrial reactive oxygen species(ROS)generation in HK-2 cells.Mechanistically,USP19 stabilized the TAK1 protein through deubiquitination.Importantly,increased TAK1 expression reversed the USP19 knockdown-mediated phenotypic changes and PINK1/Parkin pathway activation in HG+FFA-challenged HK-2 cells.Conclusion The findings revealed that USP19 plays a crucial role in promoting HK-2 cell dysfunction induced by combined stimulation with HG and FFAs by stabilizing TAK1,providing a potential therapeutic strategy for combating DN.展开更多
Objective To reveal the effects and related mechanisms of chlorogenic acid(CGA)on intestinal glucose homeostasis.Methods Forty male Sprague-Dawley rats were randomly and equally divided into four groups:normal chow(NC...Objective To reveal the effects and related mechanisms of chlorogenic acid(CGA)on intestinal glucose homeostasis.Methods Forty male Sprague-Dawley rats were randomly and equally divided into four groups:normal chow(NC),high-fat diet(HFD),HFD with low-dose CGA(20 mg/kg,HFD-LC),and HFD with high-dose CGA(90 mg/kg,HFD-HC).The oral glucose tolerance test was performed,and fast serum insulin(FSI)was detected using an enzyme-linked immunosorbent assay.The m RNA expression levels of glucose transporters(Sglt-1 and Glut-2)and proglucagon(Plg)in different intestinal segments(the duodenum,jejunum,ileum,and colon)were analyzed using quantitative real-time polymerase chain reaction.SGLT-1 protein and the morphology of epithelial cells in the duodenum and jejunum was localized by using immunofluorescence.Results At both doses,CGA ameliorated the HFD-induced body weight gain,maintained FSI,and increased postprandial 30-min glucagon-like peptide 1 secretion.High-dose CGA inhibited the HFD-induced elevation in Sglt-1 expression.Both CGA doses normalized the HFD-induced downregulation of Glut-2 and elevated the expression of Plg in all four intestinal segments.Conclusion An HFD can cause a glucose metabolism disorder in the rat intestine and affect body glucose homeostasis.CGA can modify intestinal glucose metabolism by regulating the expression of intestinal glucose transporters and Plg,thereby controlling the levels of blood glucose and insulin to maintain glucose homeostasis.展开更多
Candida antarctica lipase B (CAL-B) was used as a catalyst in the synthesis of palmitolyglucose ester in the ionic liquids, 1-butyl-3-methylimidazolium triflu- oromethanesulfonate ([Bmim][TfO]), with glucose as a subs...Candida antarctica lipase B (CAL-B) was used as a catalyst in the synthesis of palmitolyglucose ester in the ionic liquids, 1-butyl-3-methylimidazolium triflu- oromethanesulfonate ([Bmim][TfO]), with glucose as a substrates and palmitic acid vinyl ester as the acyl donor. The effect of substrate ratio, lipase content, and temperature on the activity and stability of lipase was studied. The reaction conditions in [Bmim][TfO] re- sulting in the highest yield of the sugar ester were a temperature of 50?C, enzyme concentration of 50 mg/ mL, and a molar ratio of glucose/vinyl palmitate of 1:3. The major reaction product was purified and char- acterized by FT-IR, HPLC, MS and NMR, as being 6-O-palmitolyglucose ester. The advantages of ionic liquid vs. organic solvent were noted.展开更多
s To investigate the effects of glucose and free fatty acids (FFAs) on the proliferation and cell cycle of human vascular endothelial cells in vitro , and to examine whether the combined presence of elevated FFAs ...s To investigate the effects of glucose and free fatty acids (FFAs) on the proliferation and cell cycle of human vascular endothelial cells in vitro , and to examine whether the combined presence of elevated FFAs and glucose may cross amplify their individual injurious effects Methods Cultured human vascular endothelial cells (ECV304) were incubated with various concentrations of glucose and/or FFAs (palmitate and/or oleate) for 24-96 h Morphologic alterations were observed using a phase contrast microscope and an electron microscope Inhibition of proliferation was measured by a colorimetric 3 [4, 5 dimethyl thiazol 2 yl] 2, 5 diphenyltetrazolium bromide (MTT) assay Cell viability was determined using trypan blue exclusion Distribution of cells along phases of the cell cycle was analyzed by flow cytometry Results Glucose 15 or 30 mmol/L, palmitate (PA) 0 25 or 0 5 mmol/L, and oleate (OA) 0 5 mmol/L inhibited proliferation and accelerated death of endothelial cells in a dose and time dependent manner After treatment with elevated glucose and/or FFAs, the G 0/G 1 phase cells increased, whereas S phase cells decreased, suggesting that high glucose and/or FFAs mainly arrested endothelial cells at G 0/G 1 phase The inhibitive rates of proliferation and population of dead cells in endothelial cells incubated with glucose plus FFAs (glucose 30 mmol/L+PA 0 25 mmol/L, glucose 30 mmol/L+OA 0 5 mmol/L, glucose 30 mmol/L+PA 0 25 mmol/L+OA 0 5 mmol/L) increased more markedly than those treated with high glucose or FFAs (PA and/or OA) alone Conclusion Both high ambient glucose and FFAs can inhibit proliferation and accelerate death of endothelial cells in vitro These changes were cross amplified in the combined presence of high levels of glucose and FFAs展开更多
基金supported by Natural Science Foundation of Shaanxi Province(No.2023-JC-YB-743 and No.2021JQ-905).
文摘Objective Obesity-induced kidney injury contributes to the development of diabetic nephropathy(DN).Here,we identified the functions of ubiquitin-specific peptidase 19(USP19)in HK-2 cells exposed to a combination of high glucose(HG)and free fatty acid(FFA)and determined its association with TGF-beta-activated kinase 1(TAK1).Methods HK-2 cells were exposed to a combination of HG and FFA.USP19 mRNA expression was detected by quantitative RT-PCR(qRT-PCR),and protein analysis was performed by immunoblotting(IB).Cell growth was assessed by Cell Counting Kit-8(CCK-8)viability and 5-ethynyl-2′-deoxyuridine(EdU)proliferation assays.Cell cycle distribution and apoptosis were detected by flow cytometry.The USP19/TAK1 interaction and ubiquitinated TAK1 levels were assayed by coimmunoprecipitation(Co-IP)assays and IB.Results In HG+FFA-challenged HK-2 cells,USP19 was highly expressed.USP19 knockdown attenuated HG+FFA-triggered growth inhibition and apoptosis promotion in HK-2 cells.Moreover,USP19 knockdown alleviated HG+FFA-mediated PTEN-induced putative kinase 1(PINK1)/Parkin pathway inactivation and increased mitochondrial reactive oxygen species(ROS)generation in HK-2 cells.Mechanistically,USP19 stabilized the TAK1 protein through deubiquitination.Importantly,increased TAK1 expression reversed the USP19 knockdown-mediated phenotypic changes and PINK1/Parkin pathway activation in HG+FFA-challenged HK-2 cells.Conclusion The findings revealed that USP19 plays a crucial role in promoting HK-2 cell dysfunction induced by combined stimulation with HG and FFAs by stabilizing TAK1,providing a potential therapeutic strategy for combating DN.
基金supported by the National Natural Science foundation of China(No.31071531)the Scientific Research Fund of the Hunan Provincial Education Department(No.14A071)the China National Tobacco Corp Hunan Branch(15-17Aa04)
文摘Objective To reveal the effects and related mechanisms of chlorogenic acid(CGA)on intestinal glucose homeostasis.Methods Forty male Sprague-Dawley rats were randomly and equally divided into four groups:normal chow(NC),high-fat diet(HFD),HFD with low-dose CGA(20 mg/kg,HFD-LC),and HFD with high-dose CGA(90 mg/kg,HFD-HC).The oral glucose tolerance test was performed,and fast serum insulin(FSI)was detected using an enzyme-linked immunosorbent assay.The m RNA expression levels of glucose transporters(Sglt-1 and Glut-2)and proglucagon(Plg)in different intestinal segments(the duodenum,jejunum,ileum,and colon)were analyzed using quantitative real-time polymerase chain reaction.SGLT-1 protein and the morphology of epithelial cells in the duodenum and jejunum was localized by using immunofluorescence.Results At both doses,CGA ameliorated the HFD-induced body weight gain,maintained FSI,and increased postprandial 30-min glucagon-like peptide 1 secretion.High-dose CGA inhibited the HFD-induced elevation in Sglt-1 expression.Both CGA doses normalized the HFD-induced downregulation of Glut-2 and elevated the expression of Plg in all four intestinal segments.Conclusion An HFD can cause a glucose metabolism disorder in the rat intestine and affect body glucose homeostasis.CGA can modify intestinal glucose metabolism by regulating the expression of intestinal glucose transporters and Plg,thereby controlling the levels of blood glucose and insulin to maintain glucose homeostasis.
文摘Candida antarctica lipase B (CAL-B) was used as a catalyst in the synthesis of palmitolyglucose ester in the ionic liquids, 1-butyl-3-methylimidazolium triflu- oromethanesulfonate ([Bmim][TfO]), with glucose as a substrates and palmitic acid vinyl ester as the acyl donor. The effect of substrate ratio, lipase content, and temperature on the activity and stability of lipase was studied. The reaction conditions in [Bmim][TfO] re- sulting in the highest yield of the sugar ester were a temperature of 50?C, enzyme concentration of 50 mg/ mL, and a molar ratio of glucose/vinyl palmitate of 1:3. The major reaction product was purified and char- acterized by FT-IR, HPLC, MS and NMR, as being 6-O-palmitolyglucose ester. The advantages of ionic liquid vs. organic solvent were noted.
文摘s To investigate the effects of glucose and free fatty acids (FFAs) on the proliferation and cell cycle of human vascular endothelial cells in vitro , and to examine whether the combined presence of elevated FFAs and glucose may cross amplify their individual injurious effects Methods Cultured human vascular endothelial cells (ECV304) were incubated with various concentrations of glucose and/or FFAs (palmitate and/or oleate) for 24-96 h Morphologic alterations were observed using a phase contrast microscope and an electron microscope Inhibition of proliferation was measured by a colorimetric 3 [4, 5 dimethyl thiazol 2 yl] 2, 5 diphenyltetrazolium bromide (MTT) assay Cell viability was determined using trypan blue exclusion Distribution of cells along phases of the cell cycle was analyzed by flow cytometry Results Glucose 15 or 30 mmol/L, palmitate (PA) 0 25 or 0 5 mmol/L, and oleate (OA) 0 5 mmol/L inhibited proliferation and accelerated death of endothelial cells in a dose and time dependent manner After treatment with elevated glucose and/or FFAs, the G 0/G 1 phase cells increased, whereas S phase cells decreased, suggesting that high glucose and/or FFAs mainly arrested endothelial cells at G 0/G 1 phase The inhibitive rates of proliferation and population of dead cells in endothelial cells incubated with glucose plus FFAs (glucose 30 mmol/L+PA 0 25 mmol/L, glucose 30 mmol/L+OA 0 5 mmol/L, glucose 30 mmol/L+PA 0 25 mmol/L+OA 0 5 mmol/L) increased more markedly than those treated with high glucose or FFAs (PA and/or OA) alone Conclusion Both high ambient glucose and FFAs can inhibit proliferation and accelerate death of endothelial cells in vitro These changes were cross amplified in the combined presence of high levels of glucose and FFAs
