Effect Of Ketamine On Glucose Uptake In Astrocytes And Its Machanism

Backgroud and objective:Related studies have shown that ketamine rapidly alleviates depression symptoms,while increases glucose metabolism in neurons and astrocytes.However,it has still remained elusive how ketamine could increase brain glucose metabolism.This study aimed to investigate the effect of ketamine on glucose uptake in astrocytes and its mechanism.Methods:The normal human astrocyte cell line（HA1800）was cultured as research object:（1）Effect of ketamine on glucose uptake in HA1800 cells:after the treatment of 50μmol/L ketamine for 0,0.5,3,6,12,24 h respectively and the treatment with 0μmol/L,10μmol/L,25μmol/L,50μmol/L,100μmol/L,200μmol/L ketamine for 6h respectively,2-[N-（7-Nitrobenz-2-oxa-1,3-diazol-4-yl）Amino]-2-Deoxyglucose（2-NBDG）,as a fluorescence probe,was added to detect the glucose uptake in cells.（2）Effect of ketamine on the expression of glucose transporters（GLUTs）and related signal pathway proteins:after the treatment with 0μmol/L,10μmol/L,25μmol/L,50μmol/L,100μmol/L ketamine for 6h respectively,the expression levels of GLUTs,ERK1/2,AKT and AMPK proteins were measured by western blot analysis.（3）Effect of ketamine on intracellular location of P-ERK1/2 in astrocytes:after the treatment with 0μmol/L and 50μmol/L ketamine for 6h respectively,immunostaining was used to detect location of P-ERK1/2 in astrocytes.（4）Effect of ketamine on glucose uptake and the expression of GLUT3 and ERK1/2 after inhibition of ERK1/2 activity（FR180204）:after the treatment with 0μmol/L ketamine,50μmol/L ketamine,10μmol/L FR180204+50μmol/L ketamine and 10μmol/L FR180204 for 6h respectively,glucose uptake and the expression of GLUT3 and ERK1/2 were measured.（5）Effect of ketamine on the lactate contents in cells medium:after the treatment with 0μmol/L ketamine,50μmol/L ketamine,10μmol/L FR180204+50μmol/L ketamine and 10μmol/L FR180204 for 6h respectively,lactate contents in cells medium was measured by a lactic acid detection kit.Results:（1）Compared with control（0h）,50μmol/L ketamine for 6h increased the glucose uptake(P_6h=0.018).Compared with control（0μmol/L）,the treatment with 25μmol/L,50μmol/L,100μmol/L ketamine significantly increased the glucose uptake(P_25μmol/L=0.0033,P_50μmol/L=0.0001,P_100μmol/L=0.0074).（2）Compared with control（0μmol/L）,50μmol/L ketamine for 6h significantly increased the expression levels of GLUT3(P_50μmol/L=0.014)and P-ERK1/2(P_50μmol/L=0.0069).（3）Compared with control（0μmol/L）,50μmol/L ketamine for 6h induced translocation of P-ERK1/2 into nucleus from cytoplasm.（4）Compared with 50μmol/L ketamine group,10μmol/L FR180204+50μmol/L ketamine group reduced the glucose uptake(P_{ketamine+FR180204}=0.0379)and the expression of GLUT3(P_ketamine=0.0025)and P-ERK1/2(P_{ketamine+FR180204}=0.0042)in astrocytes.（5）Compared with control（0μmol/L）,50μmol/L ketamine significantly increased lactate contents in cells medium(P_ketamine=0.0315).Compared with 50μmol/L ketamine group,there was no statistical significance in 10μmol/L FR180204+50μmol/L ketamine group(P_{ketamine+FR180204}=0.6867).Conclusion:Ketamine increases the glucose uptake and expression of GLUT3 through ERK1/2 signaling pathway,and ketamine still promotes the product of lactate in astrocytes.