A Single Bout of Physical Exercise Mimicking a Motor Seizure Increases Serum MMP-9, but Not S100B

MMP-9 and S100B, the proteins involved in blood-brain barrier integrity, are widely studied as biomarkers in many diseases, including epilepsy. They are elevated in epilepsy patients both interictally and following motor seizures. To determine whether motor activity influences their serum concentrations, we investigated the effects of brief, seizure-like physical exercise on serum MMP-9 and S100B levels in healthy individuals. Participants performed two different 5-min exercise protocols mimicking the motor activity of bilateral tonic-clonic seizures, one of the sets of exercises that contribute to to muscle failure. Serum samples were collected before exercise, 3 h after exercise, and the next day (time points 0, 3 h, and 24 h). Our results demonstrated that both sets of motor exercises led to a similar increase in MMP-9 levels, while neither affected S100B levels. No significant differences in MMP-9 levels were observed due to muscle failure. We suggest that the increase in MMP-9 seen after seizures is induced partially by peripheral mechanisms, such as muscle contraction. S100B appears to be a promising biomarker in epilepsy, as it is not induced by physical activity but does increase following seizures. Further research is needed to fully elucidate the mechanisms underlying biomarker release in epilepsy and to determine the specific contributions of muscle contractions versus other seizure-related processes.