Researchers here demonstrate that a specific lactic acid bacteria species administered as a probiotic can improve immune function in aged mice by reducing chronic inflammation. Further work may isolate exactly which molecular interactions are involved, and thus move the research aim from a potential probiotic treatment to a potential small molecule drug or supplement, but for now the probiotic is the near term outcome.
Lactic acid bacteria (LABs) are present in various foods. Long-term administration of LABs to aged mice suppresses systemic and T cell-specific aging by inhibiting inflammasome activation. In particular, certain kefir-derived LAB strains, such as Lentilactobacillus kefiri DH5, exhibits anti-inflammatory activity. Notably, the potential effect of L. kefiri YRC2606, a strain isolated from kefir, on immunosenescence has not yet been evaluated.
We hypothesized that YRC2606 attenuates immunosenescence via IL-6/STAT3 suppression. Therefore, we examined changes in organ indices, cellular senescence, and age-associated chronic inflammation following the oral administration of YRC2606 to aged mice. YRC2606 treatment significantly increased the thymus index, reduced senescence marker expression in the spleen and kidney, and decreased proinflammatory cytokine levels in serum and tissues. Furthermore, phosphorylation of STAT3, a key mediator of inflammation and senescence, was notably suppressed in the YRC2606 group. The results of this study suggest that orally administered YRC2606 regulates immunosenescence by attenuating age-related chronic inflammation.
