Extra Virgin Olive Oil alleviates articular cartilage damage and reduces ox-LDL and oxidative stress in monosodium iodoacetate-induced osteoarthritis in rats.

Objective: This study aimed to evaluate the therapeutic effects of extra virgin olive oil (EVOO), known for its antioxidant and cytoprotective properties, in a monosodium iodoacetate (MIA)-induced rat model of osteoarthritis (OA).

Methods: Twenty-one male Wistar rats were randomly divided into three groups: Control, OA, and EVOO-treated. OA was induced via intra-articular injection of MIA. The EVOO Group received a diet supplemented with EVOO for 21 days post-induction. Histopathological, immunohistochemical, biochemical, and radiological analyses were performed to evaluate cartilage damage, inflammation, apoptosis and oxidative stress.

Results: Histopathological evaluation revealed moderate cartilage destruction and synovitis in the OA Group, which were reduced in the EVOO-treated Group. Safranin-O staining confirmed higher proteoglycan preservation with EVOO supplementation. Immunohistochemistry demonstrated low intensity of oxidized low-density lipoprotein (ox-LDL) in the EVOO-treated Group compared to the OA Group. TUNEL staining indicated a significant reduction in chondrocyte apoptosis in EVOO-fed rats. Biochemically, ox-LDL and other oxidative stress markers, including total oxidative status (TOS) and oxidative stress index (OSI), were significantly reduced in the EVOO Group compared to the OA Group (p < 0.05). In contrast, the antioxidant capacity (TAC) level was significantly higher in the EVOO Group (p < 0.05). A positive correlation was observed between ox-LDL and TOS (p = 0.005).

Conclusions: Our findings suggest that EVOO may contribute to cartilage preservation and reduce synovitis in rats with MIA-induced OA. Additionally, EVOO exhibits significant antioxidant effects by reducing ox-LDL and oxidative stress markers and enhancing antioxidant capacity. These results may highlight EVOO as a potential adjuvant therapy for managing OA. Key Points • This study evaluates the therapeutic effects of extra virgin olive oil (EVOO) in a monosodium iodoacetate (MIA)-induced rat model of osteoarthritis (OA). • EVOO supplementation reduced cartilage destruction, synovitis, and chondrocyte apoptosis, while preserving proteoglycan content in the cartilage matrix, as demonstrated by histopathological and immunohistochemical findings. • Significant reductions in oxidized low-density lipoprotein (ox-LDL) and other oxidative stress markers, including total oxidative status (TOS), and oxidative stress index (OSI), were observed in EVOO-fed rats, as confirmed by biochemical analyses. • EVOO shows potential as an adjuvant therapy for managing osteoarthritis due to its antioxidant and cartilage-protective properties.