Vanillic acid attenuates cartilage degeneration by regulating the MAPK and PI3K/AKT/NF-κB pathways.

Osteoarthritis (OA) is a frequently seen arthropathy that features cartilage loss and destruction. Vanillic acid (VA), is a well-known flavonoid, which possesses various pharmacological activities. However, the effects of Vanillic acid on articular cartilage destruction and the pathogenesis of OA remain unknown. The present study observed that VA attenuated OA progression in vivo and vitro. VA inhibited the expression of inflammation responses, including cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), matrix metalloproteinases (MMPs) and aggrecanase -2(ADAMTS5). Moreover, the major markers of hypertrophic chondrocytes such as Collagen X, Runt related transcription factor 2 (Runx2) and Vascular endothelial growth factor (VEGFA) were also reduced by VA. In addition, the interleukin-1β (IL-1β) -stimulated collagen 2 and aggrecan destruction were suppressed by VA. Moreover, VA concentration -dependently inhibited IL-1β induced production of High-mobility group box 1 (HMGB1), a classic damage-associated molecular pattern (DAMP) molecule with strong pro-inflammatory effects in OA. Meanwhile, we revealed that VA suppressed the IL-1β induced activation of MAPK and PI3K/AKT/NF-κB pathways. In vivo, VA alleviated osteoarthritis progression in a rat OA model. Collectively, our results demonstrate that VA could potentially be a new candidate for OA therapy.