Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin, China.
School of Life Science, Huzhou University, Huzhou, China.
Front Immunol. 2022 Jun 2;13:915657. doi: 10.3389/fimmu.2022.915657. eCollection 2022.
To investigate the effects of alpha-ketoglutarate (AKG) supplementation in a low protein (LP) diet on the growth performance, immune response, and intestinal health of common carp (), 600 carp were randomly divided into five dietary groups: a normal protein (NP) diet containing 32% crude protein, an LP diet formulated with 28% crude protein, and LP with AKG at 0.4%, 0.8%, and 1.2% (dry matter). After an 8-week trial period, the results demonstrated that an LP diet led to a decrease in performance, immune response, and intestinal barrier function. Compared with the LP group, the final body weight and weight gain rate in the LP+0.4% AKG group were significantly higher, the feed conversion ratio was significantly decreased with the addition of 0.4% and 0.8% AKG. The supplementation with 0.4% and 0.8% AKG markedly increased the activities of T-SOD and GSH-Px, as well as the expression levels of and relative to the LP group, whereas the MDA content was significantly decreased in the LP+0.4% AKG group. In addition, the expression levels of tight junctions including , , , and were significantly up-regulated in the LP+0.4% AKG group, and the relative expression levels of the pro-inflammatory factors and were significantly lower with the addition of 0.4%, 0.8%, and 1.2% AKG. Moreover, the abundance of in the LP+0.4% AKG group was lower than that in the LP group, and the abundance of and was higher at the phylum level. The abundance of in the LP+0.4% AKG group was decreased compared to the LP group, while the abundance of was increased at the genus level. In short, the effects of AKG on the intestinal health of the common carp were systematically and comprehensively evaluated from the perspectives of intestinal physical barrier, chemical barrier, biological barrier, and immune barrier. We found that an LP diet supplemented with 0.4% AKG was beneficial to the growth performance and intestinal health of common carp.
为了研究在低蛋白（LP）饮食中添加α-酮戊二酸（AKG）对鲤鱼生长性能、免疫反应和肠道健康的影响，将 600 条鲤鱼随机分为 5 个饮食组：含 32%粗蛋白的正常蛋白（NP）饮食、含 28%粗蛋白的 LP 饮食和 LP+AKG 组（分别为 0.4%、0.8%和 1.2%干物质）。经过 8 周的试验期，结果表明 LP 饮食导致性能、免疫反应和肠道屏障功能下降。与 LP 组相比，LP+0.4%AKG 组的末重和增重率显著提高，饲料转化率显著降低，添加 0.4%和 0.8%AKG 时，0.4%和 0.8%AKG 组的 T-SOD 和 GSH-Px 活性显著升高，而 LP+0.4%AKG 组的 MDA 含量显著降低。此外，LP+0.4%AKG 组紧密连接相关基因、、、和的表达水平显著上调，添加 0.4%、0.8%和 1.2%AKG 时促炎因子和的相对表达水平显著降低。此外，LP+0.4%AKG 组的丰度低于 LP 组，而门水平的和丰度较高。与 LP 组相比，LP+0.4%AKG 组的丰度降低，而属水平的丰度增加。总之，从肠道物理屏障、化学屏障、生物屏障和免疫屏障的角度系统全面地评价了 AKG 对鲤鱼肠道健康的影响。我们发现，在 LP 饮食中添加 0.4%AKG 有利于鲤鱼的生长性能和肠道健康。
