Dietary Luffa cylindrica (L.) Roem promotes branched-chain amino acid catabolism in the circulation system via gut microbiota in diet-induced obese mice.

High circulating branched-chain amino acid (BCAA) levels can be diagnosis indicators for obesity. Luffa cylindrica (luffa) is one of vegetables against obesity. However, whether the anti-obesity of luffa is associated with BCAA metabolism and gut microbiota remains unknown. Here, we used conventionally raised diet-induced obese (DIO) mice to prove dietary luffa could reduce higher circulating BCAA levels and upregulate the tissue-specific expressions of BCAA-catabolizing enzymes. Meanwhile, dietary luffa selectively decreased the relative abundances of g_Enterortabdus, g_Eubacterium_xylanophilum_group and g_Butyricicoccus that exhibited significantly positive correlations with BCAA levels, BMI and HOMA-IR. Bacterial functionality prediction indicated dietary luffa potentially inhibited bacterial BCAA biosynthesis for reducing BCAAs supplementation. More importantly, dietary luffa had no impacts on BCAA catabolism in germ-free-mimic DIO mice. Thus, dietary luffa improved BCAA dysfunction via gut microbiota to attenuate obesity. This study offers a novel insight into dietary intervention against obesity from the aspect of gut microbiota-amino acid metabolism.

Zhang L ，Yue Y ，Shi M ，Tian M ，Ji J ，Liao X ，Hu X ，Chen F ... -  《-》

The modulation of Luffa cylindrica (L.) Roem supplementation on gene expression and amino acid profiles in liver for alleviating hepatic steatosis via gut microbiota in high-fat diet-fed mice: insight from hepatic transcriptome analysis.

Luffa cylindrica is a nutrient-dense vegetable with medical properties and can alleviate metabolic diseases. Numerous evidences demonstrated gut microbiota impacted the progress of nonalcoholic fatty liver disease (NAFLD). This study was to investigate the underlying mechanism of L. cylindrica supplementation against NALFD via gut microbiota from hepatic transcriptional and metabolic analysis. In diet-induced obese mice, we observed L. cylindrica supplementation (2 g/kg body weight) effectively alleviated high-fat diet-induced obese symptoms such as body weight, fat deposition, and insulin resistance. Notably, L. cylindrica supplementation significantly relieved hepatic steatosis and inflammation infiltration to decrease hepatic toxicity. RNA-sequencing analysis showed that 130 hepatic genes in total significantly altered responding to L. cylindrica supplementation. And signaling pathway analysis revealed that L. cylindrica supplementation down-regulated the transcriptional expressions of CD36 and Rxrg to inhibit hepatic lipid synthesis. Moreover, L. cylindrica supplementation increased the transcriptional expressions of Ass1, Cps1, Cth, Got1, Tat, and Gls2 to enhance amino acid levels (Gly, Ala, Pro, Val, Ile, Asn, Met, and Phe) and improve hepatic abnormal gluconeogenesis. Furthermore, in antibiotic-treated obese mice, L. cylindrica supplementation did not change these gene expressions along with the hepatic levels of lipid and amino acids. Taken together, L. cylindrica supplementation could effectively suppress hepatic steatosis in diet-induced obese mice through inhibiting lipid synthesis and enhancing amino acid levels in liver, which depended on gut microbiota. Thus, L. cylindrica might be one promising dietary supplementation targeting at gut microbiota to reduce NAFLD risk.

Zhang L ，Wang P ，Shi M ，Fang Z ，Ji J ，Liao X ，Hu X ，Chen F ... -  《-》

Gut microbiota determines the prevention effects of Luffa cylindrica (L.) Roem supplementation against obesity and associated metabolic disorders induced by high-fat diet.

Zhang L ，Shi M ，Ji J ，Hu X ，Chen F ... -  《-》

Dietary Folic Acid Supplementation Inhibits HighFat DietInduced Body Weight Gain through Gut Microbiota-Associated Branched-Chain Amino Acids and Mitochondria in Mice.

Han W ，Li M ，Yang M ，Chen S ，Lu Y ，Tang T ，Wang R ，Zhang C ，Qi K ... -  《-》

Berberine alleviates insulin resistance by reducing peripheral branched-chain amino acids.

Yue SJ ，Liu J ，Wang AT ，Meng XT ，Yang ZR ，Peng C ，Guan HS ，Wang CY ，Yan D ... -  《-》