Effects of pasteurized Akkermansia muciniphila on lipid metabolism disorders induced by high-fat diet in zebrafish (Danio rerio)

Akkermansia muciniphila (Akk) is an important probiotic that can help alleviate metabolic disorders. Recent research indicates that pasteurized Akkermansia muciniphila (P-Akk) is even more effective. To investigate the effect of P-Akk on improving lipid metabolism disorders caused by a high-fat diet (HFD) in fish, zebrafish were fed two HFDs containing 0 (HFD group, as control) and 1 × 10 9 CFU/g P-Akk (P-Akk group) for 28 days. The addition of P-Akk significantly decreased the number of lipid droplets in the liver and improved the mitochondrial structure in the intestine, while also altering gene expression related to lipid metabolism in HFD-fed zebrafish. Furthermore, intestinal transcriptomic network analysis and results from primary intestinal cells indicated that P-Akk may enhance mitochondrial function by activating the AMPK/PGC1α pathway. Although P-Akk did not significantly alter the composition of the gut microbiota, it did increase the steady-state index of intestinal microbiota. Moreover, P-Akk upregulated the abundance of beneficial probiotics, ( Plesiomonas , Cetobacterium , and Bacillus ), while downregulating the abundance of pathogens ( Aeromonas , Pseudomonas , Acinetobacter , and Streptococcus ). Collectively, these findings indicate that P-Akk has the potential to serve as a green and safe feed additive for improving HFD-induced lipid metabolism disorders in fish. • P-Akk supplementation significantly improves lipid metabolism disorders in zebrafish fed a high-fat diet. • P-Akk alters gut mitochondrial function potentially through activation of the AMPK/PGC1α pathway. • P-Akk promotes gut microbiota homeostasis by increasing the abundance of beneficial bacteria, particularly Cetobacterium and Bacillus .