Centenarian-Sourced Lactobacillus casei Combined with Dietary Fiber Complex Ameliorates Brain and Gut Function in Aged Mice

Dietary intervention could modulate age-related neurological disorders via the gut-brain axis. The potential roles of a probiotic and the dietary fiber complex (DFC) on brain and gut function in aged mice were investigated in this study. Lactobacillus casei LTL1361 and DFC were orally administrated for 12 weeks, and the learning and memory ability, as well as the oxidative parameters, inflammatory markers, gut barrier function and microbial metabolite short-chain fatty acids (SCFAs), were investigated. LTL1361 and DFC supplementation ameliorated cognitive ability, attenuated oxidative stress in brain and inflammation in serum and colon, ameliorated gut barrier function, and increased the SCFA concentrations and gene expression of SCFA receptors. The protective effect was more significantly enhanced in aged mice treated with the combination of LTL1361 and DFC than treated with LTL1361 or DFC alone. These results could be associated with the protected morphology of pyramidal nerve cells in hippocampus of mice brain and the downregulation of apoptosis marker caspase-3 in brain and upregulation of tight junction proteins in small intestine and colon. The results indicated that Lactobacillus casei LTL1361 and DFC alleviated age-related cognitive impairment, as well as protected brain and gut function. Lactobacillus casei LTL1361 and DFC might be used as novel and promising antiaging agents in human.

Automated summary

This study found that supplementation of Lactobacillus casei LTL1361 and dietary fiber complex (DFC) can improve cognitive ability, alleviate oxidative stress and inflammation in the brain, improve gut barrier function, and increase short-chain fatty acid (SCFA) concentrations and gene expression of SCFA receptors. The protective effect was enhanced when LTL1361 and DFC were used together. These results suggest that Lactobacillus casei LTL1361 and DFC may be promising anti-aging agents.