Serum level of melatonin in patients with osteoarthritis and relation with 8-Hydroxy-2-deoxyguanosine and vitamin D

Introduction: This study was aimed to evaluate the relationship between the serum level of melatonin, 8-hydroxy-2-deoxy guanosine, and vitamin-D in patients with osteoarthritis (OA). Methods: This study enrolled 47 patients with OA and 40 healthy controls. Serum levels of melatonin and 8-hydroxy-2-deoxy guanosine (8-OH-dG) were assessed. In addition, the serum level of biomarkers of bone turnover such as calcium, phosphorous, vitamin D, and alkaline phosphatase (ALP) was measured in OA patients and controls. Results: Serum level of melatonin was significantly lower in OA patients than the controls (6.18±2.25 vs. 11.57±3.87 pg/ml, P 0.05). We found decreased calcium and vitamin D levels, and increased phosphor and ALP levels in OA patients in comparison with controls (P<0.05). Conclusion: Decreased levels of melatonin and elevated levels of 8-OH-dG might play a role in the pathogenesis of OA. Therefore, melatonin might be involved in the decreasing the DNA damage and exerting a preventive function in OA.