Boron effect on articular cartilage repair in rat

Osteoarthritis is the most common joint disorder in modern societies. Elemental boron supplementation can support the influential effect of calcium, magnesium and vitamin D in the body. In that regard, the purpose of this study was to investigate the effect of boron on damaged knee joint cartilage in rats. In this study 30 adult Sprague Dawley male rats were randomly divided into five groups: Control group with no intervention, Sham group with 50 ml saline (vehicle) injection into the right knee joint space, Mono- sodium acetate (MIA) group with 3 mg MIA injection into articular space, prophylactic group with 3 mg MIA injection into articular space and 15 mg/kg boron in drinking water, receiving daily from the first day of injection and therapeutic group with 3 mg MIA injection into articular space and 15 mg/kg boron in drinking water, receiving daily from the third week after injection. Seven weeks after injections, the animals were killed, right knee joint were fixated, decalcified and processed. Five micrometer articular slides were stained with Safranin O + Fast Green. Articular cartilage injuries were assessed in accordance with the Modified Mankin's grading system based on the rate of articular cartilage staining and the number of chondrocyte colonies in the articular cartilage. Articular cartilage staining, mean number of chondrocyte colonies and cartilage chondrocytes in MIA, therapeutic and prophylactic groups significantly reduced in compare to control. On the other hand, the degree of articular cartilage staining, mean number of chondrocyte colonies and cartilage chondrocytes were significantly increased in both therapeutic and prophylactic groups in compare to MIA group (P<0.05). In the present study, boron could greatly reduce the effects of MIA and prevent cartilage damage. It also showed a good therapeutic effect in preventing the destruction of cartilage in this osteoarthritis model.