Pediococcus acidilactici Y01 reduces HFD-induced obesity via altering gut microbiota and metabolomic profiles and modulating adipose tissue macrophage M1/M2 polarization†

Obesity-related metabolic syndrome is intimately associated with infiltrated adipose tissue macrophages (ATMs), gut microbiota, and metabolic disorders. Pediococcus acidilactici holds the potential to mitigate obesity; however, there exist strain-specific functionalities and diverse mechanisms, which deserve extensive exploration. This study aims to explore the potential of P. acidilactici Y01, isolated from traditional sour whey, in alleviating HFD-induced metabolic syndrome in mice and elucidating its underlying mechanism. The results showed that P. acidilactici Y01 could inhibit the increase of body weight gain, the deposition of fat, lipid disorders and chronic low-grade inflammation, improve glucose tolerance and insulin resistance, and could reduce adipose tissue inflammation by decreasing M1-type ATMs and increasing M2-type ATMs. Meanwhile, P. acidilactici Y01 significantly increased the abundance of potentially beneficial intestinal bacteria, such as Akkermansia, Alistipes, Bifidobacterium, Lachnospiraceae_NK4A136_group, Lactobacillus, norank_f__Muribaculaceae, and Parabacteroides, and partially restored the levels of metabolites, such as phosphatidylcholines, glycerophosphocholines, sphingolipids and unsaturated fatty acids. The fecal microbiota transplantation experiment demonstrated that P. acidilactici Y01 ameliorated obesity-related metabolic syndrome by modulating the polarization of M1/M2 ATMs mediated by gut microbiota. Overall, as a dietary supplement, P. acidilactici Y01 has good potential in the prevention and treatment of obesity.