β-Conglycinin-Induced Intestinal Porcine Epithelial Cell Damage via the Nuclear Factor κB/Mitogen-Activated Protein Kinase Signaling Pathway

Soybean allergy is a serious health risk to humans and animals; β-conglycinin is the primary antigenic protein in soybean. Intestinal porcine epithelial (IPEC-J2) cells were used as an in vitro physiological model of the intestinal epithelium to study the effects of different concentrations of soybean antigen protein β-conglycinin to identify the involved signaling pathways. The cells were divided into eight groups and either untreated or treated with different concentrations of β-conglycinin, pyrrolidine dithiocarbamate (PDTC), N_ω-nitro-l-arginine methyl ester hydrochloride (l-NAME), SP600125, and SB202190 either alone or in combination. The cells were incubated with 1, 5, and 10 mg·mL^-1 β-conglycinin or 5 mg·mL^-1 β-conglycinin and 1 μmol·L^-1 nuclear factor κB (NF-κB) inhibitor (PDTC), inducible nitric oxide synthase inhibitor (l-NAME), c-Jun N-terminal kinase (JNK) inhibitor (SP600125), and p38 inhibitor (SB202190) for 24 h, separately; controls were left untreated. The mRNA, protein, and phosphorylation levels of NF-κB, p38, and JNK were higher in the treated groups than in the control group. β-Conglycinin decreased tight junction distribution, destroyed the Cytoskeleton of IPEC-J2 cells, and caused cell death. After the addition of the inhibitors, β-conglycinin-induced IPEC-J2 cell damage was significantly reduced. β-Conglycinin caused damage to IPEC-J2 cells via the mitogen-activated protein kinase/NF-κB signaling pathway. The results of this study are crucial for exploring the mechanisms underlying allergic reactions caused by soybean antigen proteins.