Can Intra-articular 1α, 25-Dihydroxyvitamin D3 Administration Be Therapeutical in Joint Cartilage Damage?

: INTRODUCTION Vitamin D-deficiency is known to cause nerve conduction impairments, cancer and chronic diseases, as well as the pathogenesis of osteoarthritis. Our goal with this study is to evaluate the cartilage healing by applying intraarticular 1α, 25 (OH) 2D3 at different doses in rats with normal vitamin D levels and metabolism, which we made focal chondral damage model in the knee joint. MATERIAL AND METHODS 35 male Sprague-Dawley rats aged 20-24 weeks were used in our study. Both knees of rats were cartilage defected surgically on day 0. Joint injections performed at 06:00 am on 0th and 2nd days and after second injection others performed on days 9-16 and 23 following a weekly period. RESULTS In the fourth week, hematoxylin eosin staining measurements showed statistically significant difference according to the groups (p < 0.01) Metalloproteinase-13 (MMP-13) in histological staining for evaluating cartilage healing and healing levels showed statistically significant differences between the groups at first week and fourth week (p < 0.05). DISCUSSION Vitamin D, which affects many tissues through its receptors, is believed to be chondroprotective and neuroprotective by decreasing the expression of MMP in cartilage fibroblast, macrophage, lymphocyte through its intracellular receptors. To the best of our knowledge, this is the first study known to be intraarticular use of 1α, 25-dihydroxyvitamin D3. Our study has been found to be safe and successful in terms of weight, systemic PTH and 1α, 25-dihydroxyvitamin D3 levels in rats during treatment as well as better healing of cartilage damage. Key words: vitamin D3 receptor, articular cartilage, orthopedics, nerve conduction.