Taurine attenuates LPS-induced pro-inflammatory cytokine production in IPEC-J2 cells by inhibiting the TLR4-MyD88/TRIF signaling pathway.

Post-weaning diarrhea (PWD) in piglets poses a significant challenge to global swine production, primarily due to weaning stress leading to intestinal barrier dysfunction. Recent studies have identified taurine, a conditionally essential amino acid, as a crucial modulator of innate immune responses. In this study, we utilized lipopolysaccharide (LPS)-treated porcine intestinal epithelial cells (IPEC-J2) to investigate the anti-inflammatory mechanisms of taurine. Pretreatment with taurine (20 mM for 48 h) significantly reduced the LPS-induced upregulation of pro-inflammatory cytokines, including IL-1β, TNF-α, IL-6, and IFN-β (p < 0.01). Immunofluorescence, Western blotting, and qRT-PCR analyses revealed that taurine suppressed Toll-like receptor 4 (TLR4) expression, inhibited the nuclear translocation of NF-κB p65, and attenuated the phosphorylation of MAPK (p38, ERK, JNK) and IRF3. These findings indicate that taurine mitigates inflammatory cascades by targeting the TLR4-MyD88/TRIF signaling pathway, thereby protecting IPEC-J2 cells from LPS-induced damage. This study elucidates the molecular mechanisms underlying taurine's anti-inflammatory effects and supports its potential role as a nutritional immunomodulator in managing PWD.