“…Old mice showed a significant reduction in the genera Faecalibaculum, which counteracts inflammatory state and negatively associates with major proinflammatory cytokines TNF-a, IL-1b, and IL-6 (Zhu et al, 2020a(Zhu et al, , 2020b, Rikenellaceae_RC9_gut_group, a taxonomic group which is associated with a healthy metabolic state (Zheng et al, 2018;Ijaz et al, 2018;Lippert et al, 2017), and in the butyrate-producing and anti-inflammatory Oscillospiraceae (Intestinimonas) (Li et al, 2020;Bui et al, 2015). Importantly, lactic acid bacteria Lactococcus, known as a probiotic to correlate with anti-inflammatory and health benefits, decreased in old compared with young mice (Cook et al, 2018;Luerce et al, 2014). In similar analyses, the genus iScience Article Peptococcaceae, identified to both negatively contribute to TMAO levels and in vivo clot formation, was remarkably decreased in old mice versus young mice (Zhu et al, 2016).…”