Vitamin D protects against necrotising enterocolitis in newborn mice by activating the ERK signalling pathway

Abstract

necrotising enterocolitis (nec) is a serious intestinal disease that occurs in the neonatal period. The present study aimed to investigate the protective effect of vitamin d on NEC and the underlying mechanisms. Artificial feeding and hypoxia-cold stimulation were used to establish a mouse nec model. iec-6 cells were treated with lipopolysaccharide (lPS) to establish the in vitro nec model. changes in the levels of interleukin (il)-6, il-1β and tumour necrosis factor (TnF)-α, and activities of malondialdehyde (Mda) and glutathione peroxidase (GPx) were investigated via eliSa kits. in addition, mrna expression of il-6, il-1β and TnF-α and protein expression of phosphorylated (p)-erK1/2, Ki67, cleaved caspase-3 and Bcl-2 in intestinal tissues were determined via reverse transcription-quantitative Pcr and western blotting. cell proliferation and apoptosis were also analysed via MTT assay and flow cytometry. In NEC mice, vitamin D reduced intestinal tissue damage, decreased the mrna expression of il-6, il-1β and TnF-α, and decreased the protein expression of cleaved caspase-3 and Mda. Whereas, vitamin d increased the protein expression of Bcl-2 and Ki67 and GPx, as well as the p-erK1/2/erK1/2 ratio, in nec mice. Furthermore, vitamin d improved cell viability, increased the ratio of p-erK1/2/erK1/2, inhibited apoptosis, and decreased the mrna expression of il-6, il-1β and TnF-α in lPS-treated IEC-6 cells. The dual-specificity mitogen-activated protein kinase kinase inhibitor Pd98059 reversed the effects of vitamin D on the proliferation, apoptosis and inflammation of lPS-treated iec-6 cells. overall, vitamin d relieved nec in mice. Vitamin d promoted proliferation, and inhibited apoptosis and inflammation of LPS-treated IEC-6 cells by activating the erK signalling pathway.

Enteral Feeding Interventions in the Prevention of Necrotizing Enterocolitis: A Systematic Review of Experimental and Clinical Studies

“…Moreover, ATRA supplementation prevented NEC induced loss of Treg (preserved Foxp3 mRNA expression) and induction of Th17 cells (reduced IL17 mRNA expression) in CD4+ T cells isolated from the intestinal lamina propria [109]. In a mouse model of NEC, vitamin D decreased intestinal protein and mRNA expression of IL6, IL1β and TNFα [112].…”

“…Lactadherin [51] CGMP [129] OPN [129] Hormone/growth factor/vitamin based interventions EGF [54] HB-EGF [58] IGF1 [65] Vitamin D [112] Relaxin [107] Probiotic interventions…”

“…In addition, oral administration of the hormone relaxin increases ileal blood flow measured by laser Doppler flowmetry in a rat NEC model [107]. In a mouse NEC model, enteral vitamin D administration decreased MDA protein expression (reduced lipid oxidation) and increased GSH-Px protein expression [112].…”

“…One study investigating the effects of enteral ATRA administration found decreased levels of apoptosis in the terminal ileum intestinal crypts and preserved proliferative capacity of crypt intestinal epithelial cells in NEC protocol exposed mice [109]. In addition, vitamin D was shown to reduce cleaved caspase 3 protein expression, whereas Bcl-2 and Ki67 protein expression were increased, suggesting reduced apoptosis and increased proliferation [112].…”

Neurologic Consequences of Neonatal Necrotizing Enterocolitis

“…In addition, insulin-like growth factor (IGF-1), when administered enterally, can reduce the incidence of NEC in neonatal rats, possibly by downregulating TLR4 mRNA [112, 113]. The administration of vitamin D, often deficient in newborns with NEC, can inhibit TLR4 expression, diminishing intestinal inflammation in NEC mouse models [114]. Vitamin A and retinoic acid also appear to diminish gut inflammation, while enhancing the intestinal epithelial barrier in a murine model of NEC through the increased expression of tight junction proteins, such as occludin, claudin-1, and ZO-1 [115].…”