The decreased expression of integrin αv is involved in T-2 toxin-induced extracellular matrix degradation in chondrocytes

Abstract

T-2 toxin is one of the most toxic and common mycotoxins in grains and related products. It is considered a risk factor for Kashin-Beck disease (KBD), an endemic osteoarthritis. Both in vitro and in vivo studies have shown that T-2 toxin can cause extracellular matrix degradation; however, the underlying mechanism is unclear. Integrins have been found to regulate the expression of matrix metalloproteinases (MMPs), the ‘scissors’ of matrix proteins. In this study, we investigated whether integrin αv played a role in T-2 toxin-induced matrix degradation. Results from our study showed that the expression of integrin αv in the cartilage of rats fed T-2 toxin was reduced compared to that in rats fed a normal diet. Integrin αv was downregulated in T-2 toxin-treated C28/I2 chondrocytes, and selenium was found to have a protective effect. The expression of MMP-1, -3, -10, and −13 increased whereas that of type II collagen (Col II) protein decreased in C28/I2 cells treated with an integrin αv inhibitor. In conclusion, T-2 toxin can downregulate integrin αv expression in chondrocytes. Reduced integrin αv signalling could induce the release of MMPs, leading to matrix degradation.