Zhang Yanan, Li Xuan, Huang Guowen, Wang Haifeng, Chen Huizi, Su Yong, Yu Kaifan, Zhu Weiyun
Laboratory of Gastrointestinal Microbiology, Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
National Center for International Research on Animal Gut Nutrition, Nanjing Agricultural University, Nanjing, 210095, China.
Anim Nutr. 2022 Jun 17;10:390-398. doi: 10.1016/j.aninu.2022.06.003. eCollection 2022 Sep.
Short-chain fatty acids (SCFA) can regulate appetite by stimulating the secretion of satiety hormones. However, the impact of short-chain fatty acid propionate on the release of gut satiety hormones and appetite regulation in pigs is not completely understood. In this study, 16 pigs were infused with saline or sodium propionate through a fistula in the caecum during a 28-day experimental period. We characterized the effects of propionate administration on peptide YY (PYY) and glucagon-like peptide 1 (GLP-1) secretion from colonic tissue, and investigated the role of propionate infusion on the expression of appetite-related genes in the colon and hypothalamus. Further, the direct impact of propionate administration on the expression of orexigenic neuropeptide agouti-related protein () in hypothalamic N38 cells was also examined. The results showed that intra-cecal infusion of propionate reduced the short-term feed intake ( < 0.05) but not the long-term feed intake in pigs ( > 0.05). Propionate administration stimulated PYY and GLP-1 release from colon tissue in vivo and ex vivo ( < 0.05). It also upregulated expression in the colonic mucosa ( < 0.05). Meanwhile, the GLP-1 and PYY levels in the blood were increased after intra-cecal infusion of propionate at d 28 ( < 0.05). Additionally, intra-cecal infusion of propionate upregulated the mRNA and protein expression of free fatty acid receptor 2/3 (FFAR2/FFAR3) in the colonic mucosa ( < 0.05). Propionate infusion also downregulated the orexigenic mRNA expression ( < 0.05) and upregulated the anorexigenic cocaine-and amphetamine-regulated transcript () mRNA expression ( = 0.09) in the hypothalamus. Moreover, propionate administration directly downregulated expression in hypothalamic N38 cells in a dose-dependent manner ( < 0.05). Collectively, these findings demonstrated that cecal propionate stimulated colonic secretion of satiety hormones and suppressed appetite to reduce the short-term feed intake in pigs. This study highlights that microbial-derived propionate exerts an important role in regulating the physical functions of the host.
短链脂肪酸(SCFA)可通过刺激饱腹感激素的分泌来调节食欲。然而,短链脂肪酸丙酸酯对猪肠道饱腹感激素释放及食欲调节的影响尚未完全明确。在本研究中,16头猪在为期28天的实验期内通过盲肠瘘管输注生理盐水或丙酸钠。我们表征了丙酸盐给药对结肠组织中肽YY(PYY)和胰高血糖素样肽1(GLP-1)分泌的影响,并研究了丙酸盐输注对结肠和下丘脑中食欲相关基因表达的作用。此外,还检测了丙酸盐给药对下丘脑N38细胞中促食欲神经肽刺鼠相关蛋白(AgRP)表达的直接影响。结果表明,盲肠内输注丙酸盐可降低猪的短期采食量(P<0.05),但对长期采食量无影响(P>0.05)。丙酸盐给药在体内和体外均刺激结肠组织释放PYY和GLP-1(P<0.05)。它还上调了结肠黏膜中AgRP的表达(P<0.05)。同时,在第28天盲肠内输注丙酸盐后,血液中的GLP-1和PYY水平升高(P<0.05)。此外,盲肠内输注丙酸盐上调了结肠黏膜中游离脂肪酸受体2/3(FFAR2/FFAR3)的mRNA和蛋白表达(P<0.05)。丙酸盐输注还下调了下丘脑中促食欲的AgRP mRNA表达(P<0.05),并上调了厌食的可卡因和苯丙胺调节转录物(CART)mRNA表达(P=0.09)。此外,丙酸盐给药以剂量依赖的方式直接下调下丘脑N38细胞中AgRP的表达(P<0.05)。总的来说,这些发现表明盲肠丙酸盐刺激结肠饱腹感激素的分泌并抑制食欲,从而降低猪的短期采食量。本研究强调微生物衍生的丙酸盐在调节宿主生理功能中发挥重要作用。