Necroptosis activates NLRP3 inflammasome to drive necroinflammation in T-2 toxin-induced cartilage damage

As a highly toxic mycotoxin present in contaminated food sources, T-2 toxin disrupts skeletal development by inducing cartilage injury. However, the underlying molecular mechanisms remain unclear. Following four weeks of gavage administration of T-2 toxin (200 ng/g body weight/day) to three-week-old male C57BL/6 mice, chondrocyte death in articular cartilage was accompanied by increased levels of p-RIPK3, p-MLKL, NLRP3, cleaved caspase-1, and IL-1β. In C28/I2 chondrocytes, T-2 toxin decreased cell viability and increased LDH release, accompanied by enhanced NLRP3 inflammasome-related inflammatory responses. Pharmacological inhibition of NLRP3 by MCC950 partially reduced T-2 toxin-induced LDH release. In contrast, RIPK3 inhibition by GSK-872 significantly alleviated high-dose T-2 toxin-induced loss of C28/I2 chondrocyte viability and partially suppressed LDH release. Furthermore, GSK-872 markedly attenuated T-2 toxin-induced upregulation of NLRP3, caspase-1, and IL-1β expression. Mlkl^-/- mice exhibited reduced chondrocyte loss and matrix degradation, accompanied by decreased expression of NLRP3, cleaved caspase-1, and IL-1β following T-2 toxin exposure. Collectively, these findings demonstrate that RIPK3/MLKL-driven necroptotic signaling promotes T-2 toxin-induced chondrocyte death and contributes to NLRP3-associated necroinflammation in cartilage. Targeting the RIPK3/MLKL-NLRP3 necroinflammatory signaling axis may represent a promising therapeutic strategy against T-2 toxin-induced articular cartilage injury.