College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
Key Laboratory of Environment Correlative Dietology, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China.
Nutrients. 2024 Jun 24;16(13):2002. doi: 10.3390/nu16132002.
(1) Background: Recently, academic studies are demonstrating that the cholesterol-lowering effects of pectin oligosaccharides (POSs) are correlated to intestinal flora. However, the mechanisms of POS on cholesterol metabolisms are limited, and the observations of intestinal flora are lacking integrative analyses. (2) Aim and methods: To reveal the regulatory mechanisms of POS on cholesterol metabolism via an integrative analysis of the gut microbiota, the changes in gut microbiota structure and metabolite composition after POS addition were investigated using Illumina MiSeq sequencing and non-targeted metabolomics through in vitro gut microbiota fermentation. (3) Results: The composition of fecal gut flora was adjusted positively by POS. POS increased the abundances of the cholesterol-related bacterial groups , and , while it decreased conditional pathogenic and , showing good prebiotic activities. POS changed the composition of gut microbiota fermentation metabolites (P24), causing significant changes in 221 species of fermentation metabolites in a non-targeted metabolomics analysis and promoting the production of short-chain fatty acids. The abundances of four types of cholesterol metabolism-related metabolites (adenosine monophosphate, cyclic adenosine monophosphate, guanosine and butyrate) were significantly higher in the P24 group than those in the control group without POS addition. (4) Conclusion: The abovementioned results may explain the hypocholesterolemic effects of POS and promotion effects on cholesterol efflux of P24. These findings indicated that the potential regulatory mechanisms of citrus POS on cholesterol metabolism are modulated by cholesterol-related gut microbiota and specific metabolites.
（1）背景：最近，学术研究表明，果胶寡糖（POS）的降胆固醇作用与肠道菌群有关。然而，POS 对胆固醇代谢的作用机制有限，对肠道菌群的观察缺乏综合分析。（2）目的和方法：为了通过对肠道微生物群的综合分析揭示 POS 对胆固醇代谢的调节机制，通过体外肠道微生物群发酵使用 Illumina MiSeq 测序和非靶向代谢组学研究了 POS 添加后肠道微生物群结构和代谢产物组成的变化。（3）结果：POS 正向调节粪便肠道菌群的组成。POS 增加了与胆固醇相关的细菌群体的丰度，而降低了条件致病菌的丰度，表现出良好的益生元活性。POS 改变了肠道微生物群发酵代谢物的组成（P24），在非靶向代谢组学分析中导致 221 种发酵代谢物发生显著变化，并促进短链脂肪酸的产生。在没有 POS 添加的对照组中，四种胆固醇代谢相关代谢物（单磷酸腺苷、环单磷酸腺苷、鸟苷和丁酸盐）的丰度在 P24 组中明显高于对照组。（4）结论：上述结果可能解释了 POS 的降胆固醇作用和 P24 促进胆固醇外排的作用。这些发现表明，柑橘 POS 对胆固醇代谢的潜在调节机制是由胆固醇相关肠道菌群和特定代谢物调节的。
