Although it is well known that severe exercise induces temporary immunosuppression, it remains unclear the effect of gut microbiota on this phenomenon. In this study, to investigate the effect of gut microbiota on the lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-α production immediately after the exhaustive exercise, C3H/HeN male mice were 1) treated with or without antibiotic (AB), 2) transplanted cecal content from a 5% partially hydrolyzed guar-gum (PHGG) diet, which is classified as low viscous in dietary fiber, fed mice, and 3) intake PHGG diet for 6 wk. The mice were stimulated by LPS administration immediately after loaded forced exhaustive exercise. After the exhaustive exercise, plasma TNF-α concentration in AB mice prior to response from LPS was significantly higher than that in control mice (p<0.01). On the other hand, differences in transplanted cecal contents did not affect TNF-α production by exercise prior to LPS administration. Direct intake of PHGG, however, attenuated the increase in plasma TNF-α concentration in response to LPS, compared with both non-fiber and control diet groups (p<0.01). These results suggest that LPS-induced TNF-α production immediately after intense exercise is regulated depending on both the composition of the gut microbiota and the material being fermented.
Yano et al. (2026) studied this question.