Using the Rise and Fall of Oxidative Stress and Inflammation Post-Exercise to Evaluate the Effect of Methylsulfonylmethane Supplementation on Immune Response mRNA

<b>Background:</b> Long-duration aerobic exercise results in a similar, albeit transient rise and fall in oxidative stress and inflammation, making it a useful model to evaluate nutritional supplements targeting these physiological processes. <b>Objective:</b> To evaluate the impact of MSM supplementation on post-exercise immune response-related mRNA expression. <b>Methods:</b> In the present study, we enrolled healthy, experienced runners (five MSM and five placebo) who were supplemented with Methylsulfonylmethane (MSM; 1.0 g/d) or placebo for 30 days prior to a 21.1 km running event (120 to 150 min). Venous blood samples were collected prior to (PRE) the event, as well as 2 h and 4 h after the event to measure the expression of 700 mRNAs associated with generalized immune response. <b>Results:</b> This study is the first to demonstrate significant effects with lower MSM doses (0.5-1.0 g/d) compared to previous work using higher doses (3 g/d). We identified 29 mRNAs in four distinct immune response pathways (peripheral tissue inflammatory response, myeloid immune cell invasion, NK cell invasion/activity, and notch signaling) whose response was statistically changed with MSM at 2 h and/or 4 h. <b>Conclusions:</b> Based on the physiologic actions of the mRNA that changed, some logical potential health effects of MSM may be that it helps with the following: (1) supports muscle recovery by improving macrophage response to exercise, (2) speeds up recovery and restoration of damaged muscle tissue, (3) supports innate immune responsiveness to DAMP, and (4) reduces and/or improves resistance to oxidative stress after exercise. Future research should seek to validate how the changes observed with exercise may model to various chronic inflammatory states.