Rotundic acid alleviates hyperlipidemia in rats by regulating lipid metabolism and gut microbiota

Disturbances in lipid metabolism and dysbiosis of the gut microbiota play an important role in the progression of hyperlipidemia. Previous study indicated that Ilicis Rotundae Cortex possesses anti-hyperlipidemic activity, and rotundic acid (RA) identified as a key active compound to be incorporated into the body. The study aimed to evaluate the anti-hyperlipidemia effects of RA and explored its impact on gut microbiota and lipid metabolism, as well as its possible mechanisms for improving hyperlipidemia. The study methodology included a comprehensive evaluation of the effects of RA on steatosis markers of hyperlipidemia, lipid metabolism, and gut microbiota by assessing biochemical parameters and histopathology, lipidomics, 16S rRNA gene sequencing, and short-chain fatty acid (SCFA) assays. The results showed that RA effectively reduced body weight and the steatosis markers in serum and liver. Moreover, the lipidomic analysis revealed significant changes in plasmatic and hepatic lipid levels, and these were restored by RA. According to the results of 16S rRNA gene sequencing, RA supplementation raised the relative abundance of Bacteroidetes and Proteobacteria while decreasing the relative abundance of Firmicutes. RA significantly boosted the relative abundance of SCFAs by increasing SCFAs-producing bacteria such as Bacteroides, Alloprevotella, Desulfovibrio, etc. In summary, RA could regulate triglyceride metabolism and glycerophospholipid metabolism, restore gut microbiota structure, and increase the relative abundance of SCFAs-producing bacteria to exert its hypolipidemic effects. These findings suggest RA to be a promising therapeutic agent for hyperlipidemia.