RESUMEN
Aim To investigate whether endoplasmic reticulum stress is involved in the neurotoxicity of sodi¬um arsenite and clarify whether over-expression of 3-mercaptopyruvate sulfurtransferase (MPST) regulates endoplasmic reticulum stress induced by arsenic. Methods The SH-SY5Y cell line stably expressing the exogenous MPST gene was obtained by constructing the lentiviral vector of MPST gene. The SH-SY5Y cells were randomly divided into six groups, the SR-MPST over-expression group stably expressing the exogenous MPST gene, SH-PEB control group transfected with empty vector, the arsenite treatment group ( NaAs02 group ), TUDC A treatment group ( blocker of endoplasmic reticulum stress ) and TUDC A + NaAs02 group. Western blot was used to examine the protein expression of GRP78 and CHOP after different treatment. Results Although MPST overexpression had no significant effects on the expression of GRP78 and CHOP proteins, NaAs02 could significantly increased the protein levels of GRP78 and CHOP ( P < 0. 01 ) and the up-regulation of GRP78 and CHOP proteins caused by NaAs02 could be blocked by the treatment of TUDC A. In addition, the inhibition by MPST overexpression on the arsenic-induced increase of GRP78 and CHOP proteins (P <0. 01 ) could also be reversed by the TUDC A treatment significantly. Conclusions The GRP78/ CHOP endoplasmic reticulum stress pathway is involved in the neurotoxic damage induced by arsenic; MPST overexpression may decrease arsenic-induced endoplasmic reticulum stress.