Effect of bovine lactoferrin supplementation on intestinal inflammatory factor expression in premature rats model of necrotizing enterocolitis

Objective To investigate the protective effects of bovine lactoferrin (bLF) supplementation on intestinal mucosal tissue and its influence on of inflammatory factors in the premature rats model of necrotizing enterocolitis(NEC), and to provide the theoretical basis for prevention of NEC by bLF supplementation. Methods Premature SD rats were randomly divided into 4 groups, 25 cases in each group.Control group: oral feeding; model group : oral feeding with lipopolysaccharides(LPS) gavage + hypoxic stimulation; high dose bLF intervention group: daily bLF (7 g/L) + oral feeding with LPS gavage + hypoxic stimulation; low dose bLF intervention group: daily bLF (2 g/L) + oral feeding with LPS gavage + hypoxic stimulation.Histopathological analysis was performed by HE staining.The expression levels of interleukin-1β(IL-1β)and interleukin-6(IL-6)in intestinal mucosa were detected by enzyme linked immunosorbent assay (ELISA). Results (1) Morphological observation: the intestinal wall of model group was thin, and there were different degrees of pneumoconiosis and effusion in intestinal cavity.Under the microscopy, it could be observed that the intestinal tissue necrosis was serious, the intestinal villi fell off, glands arranged disorderly, epithelial edema was significant, the lamina propria and submucosa had severely edema and were separated, and there were a large number of inflammatory cells infiltrated.The above-mentioned manifestations were alleviated in the high-dose and low-dose bLF intervention groups, and no significant abnormalities were found in the control group.(2) The expression of IL-1β and IL-6 in intestinal tissue: the tissue concentration of IL-1β and IL-6 in the model group rats [(380.89±20.25) ng/L, (485.12±31.44) ng/L]were significantly higher than those in the control group[(270.69±45.58) ng/L, (212.62±89.46) ng/L](q =9.785, 14.030, all P 0.05; IL-6: q=-1.140, P>0.05). Conclusion Enteral bLF supplementation can alleviate the damage of intestinal tissue in NEC model of premature SD rats, inhibit the expression of IL-1β and IL-6 inflammatory factors in intestinal tissue, and have a protective effect on intestinal tissue. Key words: Bovine lactoferrin; Necrotizing enterocolitis; Interleukin-1β; Interleukin-6