LPS-induced TNF-α production is attenuated by intake with PHGG via gut microbial fermentation in mice.

Objectives: Intake of dietary fibers promotes the production of short-chain fatty acids (SCFAs), which can affect host inflammation via gut microbial fermentation. Although partially hydrolyzed guar-gum (PHGG) is a water-soluble dietary fiber with lower viscosity, its benefits in acute inflammation are yet to be determined. The aim of this study was to investigate the effect of PHGG intake on the lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-α production.

Methods: Nine-wk-old male C3 H/HeN mice were used in this study, and they were randomly divided into control diet (CD) and CD + 5% PHGG (GGCD) groups. After a dietary intervention of 6 wk, LPS (1 mg/kg) was injected into the orbital vein. Plasma TNF-α concentration and SCFAs in cecum contents were then measured. Also, the effect of gut microbiota on LPS-induced TNF-α production was evaluated in PHGG-fed mice before and after antibiotic treatment.

Results: PHGG intake accelerated a dramatic suppression of LPS-induced TNF-α production (P < 0.01). PHGG-induced low pH in feces (P < 0.05) indicates that the gut microbiota induced high fermentation. Indeed, SCFAs in cecum contents of GGCD mice were significantly higher than in the CD group (P < 0.05). Furthermore, PHGG intake after antibiotic treatment did not induce the suppression of TNF-α.

Conclusion: These results demonstrated that inflammation was inhibited by habitual PHGG ingestion, suggesting that this phenomenon might be associated with changes in gut microbiota-induced SCFAs production.