International Journal of Endocrinology and Metabolism
Volume:2 Issue: 3, sep 2004

It has previously been demonstrated that circulating levels of leptin show ethnic ifferences when controlled for the confounding influence of adiposity. This study examined leptin levels in non-obese and obese subjects with type 2 diabetes of Africanversus Caucasian origin. Non-obese and obese subjects with type 2 diabetes of either African origin living in Dar es Salaam, Tanzania (n=22) or Caucasian origin living in Malmö, Sweden (n=24) were studied by taking a fasting sample for analysis of insulin and leptin after an overnight fast. All subjects were treated with metformin alone or with sulfonylurea with or without addition of metformin. It was found that age, BMI, waist circumference, blood pressure and fasting glucose or insulin did not differ between Africans and Caucasians, when divided into obese and nonobese subjects. However, leptin levels were 50% higher in the African subjects than in the Caucasians, when controlled for gender and BMI (P=0.01). We conclude that both in non-obese and obese subjects with type 2 diabetes, leptin levels are higher among subjects of African origin than of Caucasian origin. This may be related to higher risk of cardiovascular diseases in these subjects.

soluble vascular cell adhesion molecule-1 (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1) have been shown to be elevated in patients with Graves’ disease and may play significant roles in the pathogenesis of the disease. The objective of this study was to measure the levels of sVCAM-1, sICAM-1, IL-6 and thyroid receptor stimulating antibodies (TRAb) in a cohort of hyperthyroid patients and determine their associations to thyroidhormones status, before and after 3 months therapy with carbimazole. Patients were given fixed daily dose of 20 mg arbimazole for 3 months and blood samples were collected at baseline and end of the study. Thirty-eight patients were recruited from the Endocrine Clinic, Hospital Universiti Kebangsaan Malaysia, consisting of 26 females and 12 males, age ranging from 16 to 65 years. Blood samples collected before and at end of study were analysed for TSH, Free T3, Free T4, thyroid receptor stimulating antibodies (TRAb), sVCAM-1, sICAM-1 and IL-6. TRAb level of ≤10 U/L was taken to be negative, while TRAb level of >10 U/L was considered as positive. Twenty-six patients (68%) were TRAb positive (TRAb+) and 12 patients (30%) were TRAb negative (TRAb-). Median TRAb in TRAb+ patients was 23 U/L at baseline, declining to 16.7 U/L (p<0.001) in the third 3 month. Serum sVCAM-1 levels were significantly elevated in TRAb+ patients compared to TRAb- (860 versus 499 ng/mL, p<0.001). The level decreased significantly to 537 ng/mL with treatment but remained higher than in TRAb- patients (p=0.003). Irrespective of TRAb status, all but one patient had elevated serum sICAM-1 levels that remained unaffected by carbimazole therapy. In contrast, IL-6 levels of hyperthyroid patients were within the reference range of 1.4-14.1 pg/mL. Baseline and post-treatment sVCAM-1, and not TRAb levels, were significantly correlated to thyroid hormones. Compared to other inflammatory markers, sVCAM-1 showed significant correlation to thyroid stimulating antibodies and was most sensitive to changes in thyroid status. The significance of these findings in relation to Graves’ disease warrants further investigation.

The dexamethasone test has been widely used for diagnosing hypercortisolism. We assessed the relationship between the basal and suppressed cortisol values in urine and plasma during a low-dose dexamethasone test inpatients with proved Cushing’s disease. A statistically highly significant correlation was found (for urine cortisol: r = 0.66, p <0.0001; for plasma cortisol: r = 0.94, p <0.003). These findings imply that the lower the pretest cortisol values, the lower are the suppressed values. In patients with suspected Cushing’s syndrome and only slightly elevated cortisol excretion or low plasma concentration, the outcome might easily be considered normal. This point is particularly pertinent when assessing the post-treatment status.

Turner syndrome is the most common chromosomal abnormality in females. Girls with Turner syndrome have an abmormal or missing X choromosme that causes short stature, ovarian failure, renovascular and cardiac anomalies. It has been shown that there is a endency to obesity in the Turner syndrome. This prospective study has been done to evaluate whether body mass index (BMI) is different in girls with Turner syndrome as compared to normal girls and also whether it is affected by growth hormone (GH) therapy. BMI (kg/m2) was calculated for 21 girls with Turner syndrome at baseline (at the diagnosis), and after 6 months treatement with GH 0.1 IU/kg/day subcutaneously at bedtime. The results were analyzed with the SPSS and the statistical significance was established at a p<0.05. The mean age at diagnosis was 11.2±2.9 years. Height and weight were reduced in Turner syndrome as compared to those of normal girls. BMI’s was 18.44±3.32 and 18.78±4.21 kg/m2 before and after 6-month period of GH therapy, respectively. No significant change in BMI was observed (p=0.334). This study documented that shortterm hGH administration was not associated with changes in BMI in girls with Turner syndrome.

Although thyroid nodules are usually benign, malignancy must always be ruled out. Many efforts have been made to find malignant nodules and reduce the number of nnecessary operations. In this study, our aim was to examine, after the more extensive use of fine needle aspiration (FNA), whether the incidence of cancer finding has been increased. We studied retrospectively the medical records of the patients who were operated during 1991 through 1999 in the university hospital setting. Age, sex, FNA and complete pathologic reports, and whether the lesion was multinodular or a solitary nodule, were studied. The results were then compared with those of a previous study performed in the same center a decade earlier. Patients'' age was 39±12.7 year with benign nodules, and 45±15 year with malignant lesions (P<0.001). The frequencies of pathologic lesions were: multinodular goiter, 59.5%; thyroid cancer, 30.5%; thyroid adenoma, 7.7%; and thyroiditis, 2.3%. There was no relationship between being multinodular or single nodule on one hand, and malignancy on the other. The prevalence of colloid nodular goiter in a study performed a decade earlier was 81.8%; thyroid cancer 10.2%; adenomas 6.5%; and thyroiditis 1.5%. FNAs were done for 50% in the present study, whereas this was done only in 10% of patients in the earlier study. It seems that the more widespread use of FNA is an important reason of significant increase in cancer finding.

Regular intake of n-3 fatty acids of marine origin have desirable effects on serum lipoproteins and reduce coronary vascular disease (CVD). n-3 fatty acid supplementation decreased serum triglyceride concentrations in studies in which most of the subjects were male. The effects of n-3 fatty acids supplementation in fat women especially postmenopausal fat women have received little attention. The aim of this study was to determine whether purified n-3 fatty acids have desirable effects on serum lipoproteins, malondialdehyde (MDA) and lipoprotein risk factors for CVD in postmenopausal fat women receiving hormone replacement therapy (HRT). In a double-blind, placebo- controlled trial of parallel design, 35 postmenopausal women receiving hormone replacement therapy were randomly allocated to receive 2 g purified n-3 fatty acids or placebo for 10 weeks. Serum lipoproteins and MDA were determined on days 0 and 70. Serum levels of triglycerides (TG) decreased significantly in the n-3 fatty acids group at the end of study compared to the initial values, and also compared to control group (26%, p< 0.003 and 29%, p< 0.01, respectively). In the n-3 fatty acids group, serum levels of TG/HDL-C decreased significantly at the end of the study comparedto initial values and, at the end of the study, compared to control group as well (23 %, p<0.05 and 28%, p< 0.05) Supplementation with purified n-3 fatty acids can favorably influence selected CHD risk factors, particulary by achieving marked reduction in serum TG and TG/HDL–C levels in postmenopausal fat women receiving HRT.

Abnormalities in cholesterol and homocysteine metabolism have been reported in thyroid diseases. Since elevated levels of both parameters are involved in atherogenesis, and thyroid hormones are modulators of oxidative stress. In this study, the correlation between serum levels of cholesterol, and homocysteine, and oxidative stress was assessedin patients with thyroid dysfunction. A total of 60 patients with thyroid dysfunction (30 with hypothyroidism and 30 with hyperthyroidism) were included in this study. Thirty pparently healthy sex and age-matched individuals were selected as control group. The mean age of hypothyroid, hyperthyroid and control groups were 43±7.7, 39±12 and 40±7.9 years, respectively. Serum levels of homocysteine were measured by HPLC and those of thyroid hormones (T3, T4, T3 R. uptake and TSH) by radioimmunoassay techniques. Levels of total antioxidant capacity, lipid profiles and creatinine were determined by standard methods in Cobas Mira Autoanalyzer. The mean±SD levels of homocysteine in hyperthyroid, hypothyroid and control groups were 7.79±1.44, 17.09±6.93 and 8.08±1.92 μmol/L, respectively. Comparing with control group significant elevation was noted in hypothyroid patients(p=0.0001). Significant correlation between serum levels of creatinine and that of homocysteine was observed (r=0.86, p= 0.0001). Singnificant elevation in the levels of total cholesterol and LDL-C were observed in hypothyroid patients (p<0.05). Significant reduction in the serum antioxidant capacity was found in patients suffering from hypothyroidism (p=0.01). But not in hyperthyroid subjects. Significant inverse correlationwas observed between serum levels of antioxidant capacity and those of homocysteine(r=-0.79, p=0.02), total cholesterol (r=-0.93, p= 0.02) and LDL-C (r=-0.83, p=0.001) in hypothyroid patients. This correlations were not significant in the hyperthyroid and control groups (p > 0.05). The correlation between serum levels of homocysteine, total cholesterol and LDL-C with total antioxidant capacity in hypothyroidism suggests that there is an overproduction of free radicals in these patients. It is concluded that the enhanced production of free radicals might be an important contributing factor in abnormalities seen in homocysteine and cholesterol metabolism.