Dietary cholesterol intervention could alleviate the intestinal injury of Oreochromis niloticus induced by plant-based diet via the intestinal barriers

Jiayuan Jiang; Xing Lu; Li-Xue Dong; Di Peng; Jian-Min Zhang; Juan Tian; Hua Wen; Ming Jiang

doi:10.1016/j.fsi.2024.109621

Dietary cholesterol intervention could alleviate the intestinal injury of Oreochromis niloticus induced by plant-based diet via the intestinal barriers

Fish Shellfish Immunol. 2024 May 11:150:109621. doi: 10.1016/j.fsi.2024.109621. Online ahead of print.

Authors

Jiayuan Jiang¹, Xing Lu², Li-Xue Dong³, Di Peng³, Jian-Min Zhang³, Juan Tian³, Hua Wen³, Ming Jiang⁴

Affiliations

¹ Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China.
² Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China.
³ Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China.
⁴ Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China. Electronic address: jiangming@yfi.ac.cn.

PMID: 38740230
DOI: 10.1016/j.fsi.2024.109621

Abstract

This study aims to explore the effects of supplementing cholesterol in plant-based feed on intestinal barriers (including physical barrier, chemical barrier, immune barrier, biological barrier) of GIFT strain tilapia (Oreochromis niloticus). Four isonitrogenous and isolipidic diets were prepared as follows: plant-based protein diet (Con group) containing corn protein powder, soybean meal, cottonseed meal, and rapeseed meal, with the addition of cholesterol at a level of 0.6 % (C0.6 % group), 1.2 % (C1.2 % group), and 1.8 % (C1.8 % group), respectively. A total of 360 fish (mean initial weight of (6.08 ± 0.12) g) were divided into 12 tanks with 30 fish per tank, each treatment was set with three tanks and the feeding period lasted 9 weeks. Histological analysis revealed that both the C0.6 % and C1.2 % groups exhibited a more organized intestinal structure, with significantly increased muscle layer thickness compared to the Con group (P < 0.05). Furthermore, in the C1.2 % group, there was a significant up-regulation of tight junction-related genes (claudin-14, occludin, zo-1) compared to the Con group (P < 0.05). 5-ethynyl-2'-deoxyuridine staining results also demonstrated a notable enhancement in intestinal cell proliferation within the C1.2 % group (P < 0.05). Regarding the intestinal chemical barrier, trypsin and lipase activities were significantly elevated in the C1.2 % group (P < 0.05), while hepcidin gene expression was considerably down-regulated in this group but up-regulated in the C1.8 % group (P < 0.05). In terms of the intestinal immune barrier, inflammation-related gene expression levels (tnf-α, il-1β, caspase 9, ire1, perk, atf6) were markedly reduced in the C1.2 % group (P < 0.05). Regarding the intestinal biological barrier, the composition of the intestinal microbiota indicated that compared to the Con group, both the 0.6 % and 1.2 % groups showed a significant increase in Shannon index (P < 0.05). Additionally, there was a significant increase in the abundance of Firmicutes and Clostridium in the C1.2 % group (P < 0.05). In summary, supplementation of 1.2 % cholesterol in the plant-based diet exhibits the potential to enhance intestinal tight junction function and improve the composition of intestinal microbiota, thereby significantly promoting tilapia's intestinal health.

Keywords: Cholesterol; Dietary intervention; Intestinal health; Plant-based feed; Tilapia.