Methotrexate Induces Astrocyte Cells Apoptosis By Disruption Of Folate Metabolism In Adolescent Mice

Methotrexate(MTX)is a structural analog of folic acid and dihydrofolatereductase inhibitor.MTX is frequently used to treat rheumatological,oncological,inflammatory and dermatological diseases.It is also an effective and basic drug in childhood acute lymphoblastic leukemia(ALL)treatment.MTX is associated with acute,subacute and chronic neurotoxicity,but the exact mechanisms are still not fully understood.Our recent study demonstrates the mechanism of MTX-induced apoptosis in adolescent mice astrocytes through disruption of folate metabolism.Sulforhodamine B(SRB)assay was performed to measure cell proliferation.TUNEL apoptosis assay kit and flow cytometry were used to analyze the cell apoptosis.Furthermore,the expression of GFAP,DHFR,PARPand-caspase-3 were examined by western blotting assay.MTX showed severe cytotoxicity to C6 and primary astrocytes in a dose-dependent manner.MTX significantly decreased the expression of pro-Caspase-3 and total poly ADP-ribose polymerase(PARP)in C6 and primary astrocytes.In addition,the expression of GFAP was obviously down-regulated in 2spinal cord and brain after treating the mice with MTX.Notably,we demonstrate that over-expression of DHFR or exogenous addition of folate markedly reversed the effect of MTX.Taken together,our studies provided evidence for the neurotoxic effect of MTX-induced astrocytes apoptosis both in vitro and in vivo with disruption of folate metabolism,and additional supplement of folate might provide novel approaches for alleviating the astrocyte toxicity induced by MTX in the clinic.