In a model of Porphyromonas gingivalis-induced periodontitis in HFD-fed mice, infection with the wild-type organism, but not with a mutant deficient in branched-chain amino acid (BCAA) aminotransferase, resulted in elevated serum levels of BCAAs (such as leucine, isoleucine, and valine) and insulin resistance, compared to uninfected HFD-fed mice [105]. Here, INS is linked to periodontitis.