Serum osteocalcin levels in hyperthyroidism before and after antithyroid therapy.

Hyperthyroidism is characterized by accelerated bone turnover, caused from direct stimulation of bone cells by increased thyroid hormones. In this study, we aimed to investigate serum osteocalcin levels as a bone formation marker, before antithyroid (propylthiouracil) therapy at hyperthyroid stage and after antithyroid therapy at euthyroid stage of the patients. Twenty four hyperthyroid patients (18 females, 6 males) and 20 (13 females, 7 males) healthy controls were included into this study. Blood and urine samples were taken before medical treatment at hyperthyroid state, and after the antithyroid therapy until the patients reached the euthyroid state. Serum alkaline phosphatase, osteocalcin, calcium, phosphorus, Free T3, Free T4, TSH and urine calcium/creatinine levels were assessed. We found a significant decrease in serum osteocalcin (p=0.006), urinary calcium/creatinine (p=0.004), and serum phosphorus (p=0.038) levels in euthyroid state in comparison to hyperthyroid state. The increases in serum bone formation marker osteocalcin and bone resorption marker urinary calcium/creatinine levels in hyperthyroid state compared to euthyroid state in our study confirmed that hyperthyroid patients have high bone turnover. We conclude that, hyperthyroid patients has high bone turnover of formation and resorption even after attainment of euthyroidism. Osteocalcin and urine calcium/creatinine are sensitive markers in documenting bone remodeling during treatment of hyperthyroidism.

Glycemic control, oxidative stress, and lipid profile in children with type 1 diabetes mellitus.

BACKGROUND: In diabetes mellitus, persistence of hyperglycemia was reported to cause increased production of oxidative parameters including malondialdehyde (MDA). In the present study, the effect of glycemic control on oxidative stress and the lipid profile of pediatric type 1 diabetes mellitus (DM) patients were investigated. METHODS: Serum total cholesterol, HDL cholesterol, VLDL cholesterol, apolipoprotein A, apolipoprotein B, lipoprotein a, HbA(1c), and MDA levels were assessed in 96 children with type 1 DM. Study cases were evaluated in two groups in view of their mean HbA(1c) values, as metabolically well controlled (HbA(1c) < or =8%) and poorly controlled (HbA(1c) >8%) patients with DM. Fifty healthy children were included as normal controls. RESULTS: Total cholesterol, LDL cholesterol, apolipoprotein A, apolipoprotein B, and MDA levels of total diabetic patients were significantly (p<0.05) higher than those of the control group. Serum MDA levels and MDA/LDL cholesterol index were significantly increased in metabolically poorly controlled in relation to metabolically well-controlled DM patients and were similar in metabolically well-controlled DM patients with relation to control group and in metabolically poorly controlled patients with relation to control group. CONCLUSIONS: In the present study, increased levels of MDA, MDA/LDL index, and dyslipoproteinemia showed that especially metabolically poorly controlled DM children are at high risk of atherosclerosis and vascular complications of DM and that there is a significant relationship between the lipid profile and oxidative stress. Thus, it may be appropriate to evaluate MDA in addition to routine laboratory assessments in evaluation of type 1 DM pediatric patients.