INS and Insulin resistance: The increased abundance of Butyricimonas has been reported to relate to improved metabolic parameters (including insulin resistance) in mice treated with metformin, which was associated with the downregulation of pro-inflammatory cytokine IL-6 in epididymal fat, and IL-6 levels in adipose tissue reportedly increased with age and attenuated insulin signaling in adipocytes [66,67,68,69].