title: Microsomal glutathione transferase 1 is not S-nitrosylated in rat liver microsomes or in endotoxin challenged rats.
abstract: In vitro activation of purified rat microsomal glutathione transferase 1 (MGST1) by S-nitrosylation has been recently reported. This study was designated to explore its in vivo relevance. Unexpectedly, we failed to detect S-nitrosylated MGST1 in rat liver microsomes treated with S-nitrosoglutathione (GSNO); neither did we observe MGST1 S-nitrosylation in endotoxin challenged rats. However, by using matrix-assisted laser dissociation/ionization time-of-flight mass spectrometry (MALDI-TOF MS), we identified several other proteins which are susceptible to S-nitrosylation in liver microsomes, including retinol dehydrogenase type I (RODH I), aldolase B, cytochrome P4502C11, and peroxiredoxin 1. Our results suggest that MGST1 S-nitrosylation is unlikely to be involved in the protection mechanism against nitrosative stress caused by endotoxin challenge. Further studies on the novel S-nitrosylable microsomal proteins are also warranted.
authors.affiliation: Department of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310031, PR China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Shi
authors.forename: Yi-jia
authors.initials: YJ
authors.lastname: Lou
mesh_terms: D000818:Animals; D005982:Glutathione Transferase / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000008:administration & dosage* / Q000633:toxicity; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D026422:S-Nitrosoglutathione / Q000494:pharmacology*
chemical_list: D008070:Lipopolysaccharides; D026422:S-Nitrosoglutathione; C122107:microsomal glutathione S-transferase-I; D005982:Glutathione Transferase