Wang Helin, Xie Linlin, Liu Shufan, Dai Anna, Chi Xiaoxing, Zhang Dongjie
Food Science and Technology, Heilongjiang Bayi Agricultural University, Daqing, China.
Front Nutr. 2023 Jan 11;9:1095483. doi: 10.3389/fnut.2022.1095483. eCollection 2022.
To study the prevention and mechanism of oat antimicrobial peptides (AMPs) on enteritis. Oat protein was hydrolyzed by alkaline protease and isolated to obtain oat antimicrobial peptides. Rat enteritis models were constructed using dextran sodium sulfate (DSS), and a blank group, a negative control group, a positive control group, and an experimental group (low dose, medium dose, and high dose) were established. Through pathological test, antioxidant test, intestinal microbial and metabolite determination, it was found that AMPS can improve the antioxidant capacity of colon, reduce the production of inflammatory cells, and have the effect of preventing enteritis. In addition, the AMPS group is able to change and reduce the abundance of and , increase the abundance of probiotics such as and and the diversity of intestinal microorganisms. Then, the combined analysis of microorganism and metabolites showed that and reduced the contents of amino acid and glucose and promoted the production of phospholipid, while promoted the synthesis of amino acid in the body. From the above, it can be seen that DSS causes damage to the mechanical barrier of the gut. Oat antimicrobial peptides provide a microbial barrier for the gut microbes, which produce acetic acid and succinic acid with small amounts of isobutyric acid, isovaleric acid, and lactic acid. The acidic metabolites produced reduce the pH of the gut and produce substances with antibacterial effects (such as lipophilic molecules, antibiotics, and hydroperoxides). Inhibit the growth and reproduction of other harmful bacteria, , from adhering to and colonizing the intestinal mucosa. Secreted short-chain fatty acids, such as acetate and butyric acid, maintain tight connections between the epithelial cells of the intestinal mucosa, thus protecting the mechanical barrier of the intestinal mucosa. Moreover, amino acids are converted into phospholipid metabolism through protein digestion and absorption to promote the production of phospholipid in the intestine and repair damaged cell membranes.
研究燕麦抗菌肽对肠炎的预防作用及机制。用碱性蛋白酶水解燕麦蛋白并分离得到燕麦抗菌肽。采用葡聚糖硫酸钠（DSS）构建大鼠肠炎模型，设立空白组、阴性对照组、阳性对照组和实验组（低剂量、中剂量和高剂量）。通过病理检测、抗氧化检测、肠道微生物及代谢产物测定发现，燕麦抗菌肽能提高结肠抗氧化能力，减少炎性细胞产生，具有预防肠炎的作用。此外，燕麦抗菌肽组能够改变并降低 和 的丰度，增加 、 和 等益生菌的丰度以及肠道微生物的多样性。然后，微生物与代谢产物的联合分析表明， 和 降低了氨基酸和葡萄糖含量，促进了磷脂的产生，而 促进了体内氨基酸的合成。由此可见，DSS对肠道机械屏障造成损伤。燕麦抗菌肽为肠道微生物提供微生物屏障，这些微生物产生乙酸、琥珀酸以及少量异丁酸、异戊酸和乳酸。产生的酸性代谢产物降低肠道pH值，并产生具有抗菌作用的物质（如亲脂性分子、抗生素和氢过氧化物）。抑制其他有害细菌 黏附并定植于肠黏膜。分泌的短链脂肪酸，如乙酸和丁酸，维持肠黏膜上皮细胞之间的紧密连接，从而保护肠黏膜的机械屏障。此外，氨基酸通过蛋白质消化吸收转化为磷脂代谢，促进肠道磷脂产生并修复受损细胞膜。
