BACKGROUND Uncarboxylated osteocalcin(GluOC)has been reported to improve glucose metabolism,prevent type 2 diabetes,and decrease the severity of obesity in mice with type 2 diabetes.GluOC can increase glucose uptake i...BACKGROUND Uncarboxylated osteocalcin(GluOC)has been reported to improve glucose metabolism,prevent type 2 diabetes,and decrease the severity of obesity in mice with type 2 diabetes.GluOC can increase glucose uptake in a variety of cells.Glucose metabolism is the main source of energy for osteoblast proliferation and differentiation.We hypothesized that decarboxylated osteocalcin(dcOC),a kind of GluOC,can increase glucose uptake in MG63 cells(osteoblast-like osteosarcoma cells)and influence their proliferation and differentiation.AIM To investigate the effects of dcOC on glucose uptake in human osteoblast-like osteosarcoma cells and the possible signaling pathways involved.METHODS MG63 cells(human osteoblast-like osteosarcoma cells)were treated with dcOC(0,0.3,3,10,or 30 ng/mL)for 1 and 72 h,and glucose uptake was measured by flow cytometry.The effect of dcOC on cell proliferation was measured with a CCK-8 assay,and alkaline phosphatase(ALP)enzyme activity was measured.PI3K was inhibited with LY294002,and hypoxia-inducible factor 1 alpha(HIF-1α)was silenced with siRNA.Then,GPRC6A(G protein-coupled receptor family C group 6 subtype A),total Akt,phosphorylated Akt,HIF-1α,and glucose transporter 1(GLUT1)levels were measured by Western blot to elucidate the possible pathways by which dcOC modulates glucose uptake.RESULTS The glucose uptake of MG63 cells was significantly increased compared with that of the paired control cells after short-term(1 h)treatment with dcOC at different concentrations(0.3,3,and 10 ng/mL groups,P<0.01;30 ng/mL group,P<0.05).Glucose uptake of MG63 cells was significantly increased compared with that of the paired control cells after long-term(72 h)treatment with dcOC at different concentrations(0.3,3,and 10 ng/mL groups,P<0.01;30 ng/mL group,P<0.05).DcOC triggered Akt phosphorylation in a dose-dependent manner,and the most effective stimulatory concentration of dcOC for short-term(1 h)was 3 ng/mL(P<0.01).LY294002 abolished the dcOC-mediated(1 h)promotion of Akt phosphorylation and glucose uptake without affecting GLUT1 protein expression.Long-term dcOC stimulation triggered Akt phosphorylation and increased the protein levels of HIF-1α,GLUT1,and Runx2 in a dose-dependent manner.Inhibition of HIF-1αwith siRNA abolished the dcOC-mediated glucose uptake and substantially decreased GLUT1 protein expression.DcOC interven-tion promoted cell proliferation in a time-and dose-dependent manner as determined by the CCK-8 assay.Treatment with both 3 ng/mL and 10 ng/mL dcOC affected the ALP activity in MG63 cells after 72 h(P<0.01).CONCLUSION Short-and long-term dcOC treatment can increase glucose uptake and affect proliferation and ALP activity in MG63 cells.This effect may occur through the PI3K/Akt,HIF-1α,and GLUT1 signaling factors.展开更多
The objective of this paper was to evaluate the effect of vanadium(V)in high-fat diets sourced from egg yolk on body weight gain,feed intake,blood characteristics and antioxidative status of Wistar rats.A total of 72 ...The objective of this paper was to evaluate the effect of vanadium(V)in high-fat diets sourced from egg yolk on body weight gain,feed intake,blood characteristics and antioxidative status of Wistar rats.A total of 72 female Wistar rats were allocated according to a 2 x 4 factorial design throughout a 5-wk trial,including 2 levels of dietary fat(normal and high;ether extract 40.3 and 301.2 g/kg;fat sourced from egg yolk)and 4 levels of dietary V(0,3,15 and 30 mg/kg).Vanadium decreased(P<0.05)body weight gain(V at 30 mg/kg during wk 1 and 2;V at 15 and 30 mg/kg during the overall phase),feed intake(V at30 mg/kg during wk 3 and the overall phase;V at 15 and 30 mg/kg during wk 4),but increased the relative weight of liver(V at 30 mg/kg,P<0.05).Moreover,increasing dietary V significantly increased(P<0.05)plasma aspartate aminotransferase,alanine aminotransferase and malondialdehyde levels and decreased triglyceride level,and V at 30 mg/kg in high-fat treatment had the highest or lowest values(interaction,P<0.05).Under the same dietary V dose,V residual content in liver(dietary V at 15 and30 mg/kg)and kidney(dietary V at 15 mg/kg)was higher in high-fat diet treatment compared with normal-fat diet treatment(P<0.05).In conclusion,it is suggested that V could decrease the body weight together with the feed intake,and the high fat could enhance oxidative stress induced by V of Wistar rats.展开更多
基金Supported by Provincial Science and Technology Department Natural Fund Guidance Project,No.2019-ZD-0774National Natural Science Foundation of China,No.81470998+1 种基金Liaoning Ministry of Education,No.LQNK201715and Liaoning Provincial Doctor Start up Fund,No.20180540008.
文摘BACKGROUND Uncarboxylated osteocalcin(GluOC)has been reported to improve glucose metabolism,prevent type 2 diabetes,and decrease the severity of obesity in mice with type 2 diabetes.GluOC can increase glucose uptake in a variety of cells.Glucose metabolism is the main source of energy for osteoblast proliferation and differentiation.We hypothesized that decarboxylated osteocalcin(dcOC),a kind of GluOC,can increase glucose uptake in MG63 cells(osteoblast-like osteosarcoma cells)and influence their proliferation and differentiation.AIM To investigate the effects of dcOC on glucose uptake in human osteoblast-like osteosarcoma cells and the possible signaling pathways involved.METHODS MG63 cells(human osteoblast-like osteosarcoma cells)were treated with dcOC(0,0.3,3,10,or 30 ng/mL)for 1 and 72 h,and glucose uptake was measured by flow cytometry.The effect of dcOC on cell proliferation was measured with a CCK-8 assay,and alkaline phosphatase(ALP)enzyme activity was measured.PI3K was inhibited with LY294002,and hypoxia-inducible factor 1 alpha(HIF-1α)was silenced with siRNA.Then,GPRC6A(G protein-coupled receptor family C group 6 subtype A),total Akt,phosphorylated Akt,HIF-1α,and glucose transporter 1(GLUT1)levels were measured by Western blot to elucidate the possible pathways by which dcOC modulates glucose uptake.RESULTS The glucose uptake of MG63 cells was significantly increased compared with that of the paired control cells after short-term(1 h)treatment with dcOC at different concentrations(0.3,3,and 10 ng/mL groups,P<0.01;30 ng/mL group,P<0.05).Glucose uptake of MG63 cells was significantly increased compared with that of the paired control cells after long-term(72 h)treatment with dcOC at different concentrations(0.3,3,and 10 ng/mL groups,P<0.01;30 ng/mL group,P<0.05).DcOC triggered Akt phosphorylation in a dose-dependent manner,and the most effective stimulatory concentration of dcOC for short-term(1 h)was 3 ng/mL(P<0.01).LY294002 abolished the dcOC-mediated(1 h)promotion of Akt phosphorylation and glucose uptake without affecting GLUT1 protein expression.Long-term dcOC stimulation triggered Akt phosphorylation and increased the protein levels of HIF-1α,GLUT1,and Runx2 in a dose-dependent manner.Inhibition of HIF-1αwith siRNA abolished the dcOC-mediated glucose uptake and substantially decreased GLUT1 protein expression.DcOC interven-tion promoted cell proliferation in a time-and dose-dependent manner as determined by the CCK-8 assay.Treatment with both 3 ng/mL and 10 ng/mL dcOC affected the ALP activity in MG63 cells after 72 h(P<0.01).CONCLUSION Short-and long-term dcOC treatment can increase glucose uptake and affect proliferation and ALP activity in MG63 cells.This effect may occur through the PI3K/Akt,HIF-1α,and GLUT1 signaling factors.
基金fanatically supported by Ministry of Science and Technology Support Program(2014BAD13B04)National Natural Science Foundation of China(31402031)+1 种基金Department of Education Project of Sichuan Province(13ZB0290)Department of Science and Technology Project of Sichuan Province(2014NZ0043,2014NZ0002,2013NZ0054)
文摘The objective of this paper was to evaluate the effect of vanadium(V)in high-fat diets sourced from egg yolk on body weight gain,feed intake,blood characteristics and antioxidative status of Wistar rats.A total of 72 female Wistar rats were allocated according to a 2 x 4 factorial design throughout a 5-wk trial,including 2 levels of dietary fat(normal and high;ether extract 40.3 and 301.2 g/kg;fat sourced from egg yolk)and 4 levels of dietary V(0,3,15 and 30 mg/kg).Vanadium decreased(P<0.05)body weight gain(V at 30 mg/kg during wk 1 and 2;V at 15 and 30 mg/kg during the overall phase),feed intake(V at30 mg/kg during wk 3 and the overall phase;V at 15 and 30 mg/kg during wk 4),but increased the relative weight of liver(V at 30 mg/kg,P<0.05).Moreover,increasing dietary V significantly increased(P<0.05)plasma aspartate aminotransferase,alanine aminotransferase and malondialdehyde levels and decreased triglyceride level,and V at 30 mg/kg in high-fat treatment had the highest or lowest values(interaction,P<0.05).Under the same dietary V dose,V residual content in liver(dietary V at 15 and30 mg/kg)and kidney(dietary V at 15 mg/kg)was higher in high-fat diet treatment compared with normal-fat diet treatment(P<0.05).In conclusion,it is suggested that V could decrease the body weight together with the feed intake,and the high fat could enhance oxidative stress induced by V of Wistar rats.
