College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, PR China.
Food Funct. 2024 Feb 5;15(3):1443-1459. doi: 10.1039/d3fo04916g.
As important components of the mammalian diet and tissues, fats are involved in a variety of biological processes in addition to providing energy. In general, the increase in basal metabolism and health risks under cold temperature conditions causes the host to need more energy to maintain body temperature and normal biological processes. The intestine and its microbiota are key components in orchestrating host metabolic homeostasis and immunity, and respond rapidly to changing environmental conditions. However, the role of dietary-fat supplementation in regulating host homeostasis of metabolism and barrier functions through gut microbiota at cold temperatures is incompletely understood. Our results showed that dietary-fat supplementation alleviated the negative effects of cold temperatures on the alpha-diversity of both ileal and colonic microbiota. Cold temperatures altered the ileal and colonic microbiota of pigs, and the extent of changes was more pronounced in the colonic microbiota. Translocation of the gut microbiota was restored after supplementation with a high-fat diet. In addition, cold temperatures exacerbated ileal mucosal damage and inflammation, and disrupted barrier function, which may be associated with decreased concentrations of butyrate and isobutyrate. Cold temperature-induced metabolic dysbiosis was manifested by altered hormone levels and upregulation of expression of multiple metabolites involved in metabolism (lipids, amino acids and minerals) and the immune response. Supplementation with a high-fat diet restored metabolic homeostasis and barrier function by improving gut-microbiota composition and increasing SCFAs concentrations in pigs. In conclusion, cold temperatures induced severe translocation of microbiota and barrier damage. These actions increased the risk of metabolic imbalance. Dietary-fat supplementation alleviated the adverse effects of cold temperatures on host metabolism by remodeling the gut microbiota.
脂肪作为哺乳动物饮食和组织的重要组成部分，除了提供能量外，还参与了多种生物过程。一般来说，低温条件下基础代谢的增加和健康风险会导致宿主需要更多的能量来维持体温和正常的生物过程。肠道及其微生物群是协调宿主代谢稳态和免疫的关键组成部分，能够迅速对环境条件的变化做出反应。然而，膳食脂肪补充剂通过肠道微生物群在低温下调节宿主代谢和屏障功能的稳态的作用尚不完全清楚。我们的结果表明，膳食脂肪补充剂缓解了低温对回肠和结肠微生物群 α 多样性的负面影响。低温改变了猪的回肠和结肠微生物群，而结肠微生物群的变化更为明显。高脂肪饮食补充后，肠道微生物群的易位得到了恢复。此外，低温加剧了回肠黏膜损伤和炎症，并破坏了屏障功能，这可能与丁酸和异丁酸浓度降低有关。低温诱导的代谢失调表现为激素水平改变和参与代谢（脂质、氨基酸和矿物质）和免疫反应的多种代谢物的表达上调。高脂肪饮食补充通过改善肠道微生物群组成和增加 SCFAs 浓度来恢复猪的代谢稳态和屏障功能。总之，低温会引起严重的微生物群易位和屏障损伤。这些作用增加了代谢失衡的风险。膳食脂肪补充通过重塑肠道微生物群缓解了低温对宿主代谢的不利影响。
