Dimethyl sulfide, a metabolite of the marine microorganism, protects SH-SY5Y cells against 6-hydroxydopamine and MPP+-induced apoptosis

摘要

Dimethyl sulfide (DMS) has been historically recognized as a metabolite of the marine microorganism or a disgusting component for the smell of halitosis patients. In our recent study, DMS has been identified as a cytoprotectant that protects against oxidative-stress induced cell death and aging. We found that at near- physiological concentrations, DMS reduced reactive oxygen species (ROS) in cultured PC12 cells and alleviated oxidative stress. The radical-scavenging capacity of DMS at near-physiological concentration was equivalent to endogenous methionine(Met)-centered antioxidant defense. Methionine sulfoxidereductase A (MsrA), the key antioxidant enzyme in Met-centered defense, bound to DMS and promoted its antioxidant capacity via facilitating the reaction of DMS with ROS through a sulfonium intermediate at residues Cys72, Tyr103, Glu115, followed by the release of dimethyl sulfoxide (DMSO). MTT assay and trypan blue test indicated that supplement of DMS exhibited cytopro?tection against 6-hydroxydopamine and MPP + induced cell apoptosis. Furthermore, MsrA knockdown abolished the cytoprotective effect of DMS at near- physiological concentrations. The present study reveals new insight into the potential therapeutic value of DMS in Parkinson disease.