Curcuma longa L. extract exhibits anti-inflammatory and cytoprotective functions in the articular cartilage of monoiodoacetate-injected rats

Background: Osteoarthritis (OA), the most prevalent form of arthritis, is a degenerative joint disease marked by the progressive deterioration of articular cartilage, leading to clinical manifestations such as joint pain. Objective: This study investigated the effects of Curcuma longa L. extract (CL) containing curcumin, deme-thoxycurcumin, and bisdemethoxycurcumin on monosodium iodoacetate (MIA)-induced OA rats. Design: Sprague–Dawley rats with MIA-induced OA received CL supplementation at doses of 5, 25, and 40 mg/kg body weight. Results: CL extract administration suppressed mineralisation parameters and morphological modifications and decreased arachidonate 5-lipoxygenase and leukotriene B4 levels in articular cartilage. Additionally, it decreased serum prostaglandin E2, NO, and glycosaminoglycan levels as well as the protein expression of phosphorylated inhibitor kappa B-alpha, phosphorylated p65, cyclooxygenase-2, and inducible nitric oxide synthase in the cartilage of MIA-injected rats. Furthermore, it also reduced matrix metalloproteinases and elevated SMAD family member 3 phosphorylation, tissue inhibitor of metalloproteinases, aggrecan, collagen type I, and collagen type II levels in the articular cartilage of MIA-induced OA rats. Conclusions: This study’s findings suggest that CL supplementation helps prevent OA development and is an effective therapy for OA.