RELATIONSHIP OF OXIDATIVE STRESS WITH THE INDICATORS OF BONE METABOLISM IN PATIENTS WITH TYPE 2 DIABETES MELLITUS AND OSTEOPOROSIS

The literature data indicate that there is a close relationship between carbohydrate metabolism and bone metabolism in patients with type 2 diabetes mellitus (DM). It is important to find the factors that lead to changes in bone turnover in patients with type 2 DM. One of these factors may be oxidative stress (OS). The purpose of the study analysis of the relationship between the parameters of bone metabolism and oxidative stress in patients with a combined course of diabetes mellitus type 2 and osteoporosis (OP). Materials and methods. Study of 94 patients, of which 1-st group – 22 patients with OP, 2-nd group – 22 patients with type 2 DM, 3-rd group – 50 patients with combined course of these diseases. An ultrasound densitometry on an Omnisense 7000 ultrasound densitometer (BeamMedLtd, Israel) was performed for all patients. The bone tissue assessment been performed according to the WHO criteria. The levels of osteocalcin (OK), parathyroid hormone, calcitonin in blood serum, the level deoxypyridinoline (DPD) was determined in morning urine for all patients. The OS intensity was assessed by the nitrotyrosine level in the serum. Results. In patients with a combined course of type 2 diabetes and OP bone metabolism, there is a significant reduction in the levels of OC and DPD by 44 % and 24 % compared to patients who did not have type 2 DM (p < 0.05). In patients with a combined course of type 2 DM and OP, the severity of the OS increases, which is confirmed by a significant increase in the level of nitrotyrosine in 2.8 times compared with patients with OP and 2.1 times – with type 2 DM (p < 0,05). In patients with combined course of type 2 DM and OP recorded negative relationship between bone metabolism and OS, as evidenced by the presence of significant association between levels nitrotyrosine, OC, DPD, parathyroid hormone and calcitonin. Conclusion. The relationship between nitrotyrosine and indicators of bone metabolism may indicate the significant role of reactive oxygen species in decreasing bone turnover in patients with combined course of type 2 DM and OP.