Can Supplementation with Vitamin D Modify Thyroid Autoantibodies (Anti-TPO Ab, Anti-Tg Ab) and Thyroid Profile (T3, T4, TSH) in Hashimoto's Thyroiditis? A Double Blind, Randomized Clinical Trial

Hashimoto's thyroiditis (HT) is the most prevalent autoimmune disorder characterized by the destruction of thyroid cells caused by leukocytes and antibody-mediated immune processes accompanied by hypothyroidism. In recent years, evidence has emerged pointing to various roles for vitamin D, including, proliferation and differentiation of normal and cancer cells, cardiovascular function, and immunomodulation. Vitamin D deficiency has been especially demonstrated in HT patients. The aim of this study was to investigate the effect of vitamin D on circulating thyroid autoantibodies and thyroid hormones profile (T4, T3, and TSH) in females with HT. Forty-two women with HT disease were enrolled in this randomized clinical trial study and divided into vitamin D and placebo groups. Patients in the vitamin D and placebo groups received 50 000 IU vitamin D and placebo pearls, weekly for 3 months, respectively. The serum levels of 25-hydroxy vitamin D [25(OH) D], Ca⁺⁺ion, anti-thyroperoxidase antibody (anti-TPO Ab), anti-thyroglobulin antibody (anti-Tg Ab), T4, T3, and TSH were measured at the baseline and at the end of the study using enzyme-linked immunosorbent assays. The results of this study showed a significant reduction of anti-Tg Ab and TSH hormone in the Vitamin D group compared to the start of the study; however, there was a no significant reduction of anti-TPO Ab in the Vitamin D group compared to the placebo group (p=0.08). No significant changes were observed in the serum levels of T3 and T4 hormones. Therefore, vitamin D supplementation can be helpful for alleviation of the disease activity in HT patients; however, further well controlled, large, longitudinal studies are needed to determine whether it can be introduced in clinical practice.

Western dietary pattern increases risk of cardiovascular disease in Iranian adults: a prospective population-based study

Limited data are available regarding the association of major dietary patterns and risk of cardiovascular disease (CVD) in Middle Eastern countries. We aimed to evaluate the association of major dietary patterns, using factor analysis, with the risk of CVD. Participants without CVD (n = 2284) were recruited from the Tehran Lipid and Glucose Study and were followed for a mean of 4.7 years. Dietary intake of participants was assessed at baseline (2006-2008); biochemical variables were evaluated at baseline and follow-up examination. Multivariate Cox proportional hazard regression models, adjusted for potential confounders, were used to estimate risk of CVD across tertiles of dietary pattern scores. Linear regression models were used to indicate association of dietary pattern scores with changes of CVD risk factors over the study period. Two major dietary patterns, Western and traditional, were identified. During a mean 4.7 ± 1.4 years of follow-up, 57 participants experienced CVD-related events. In the fully adjusted model, we observed an increased risk of CVD-related events in the highest compared to the lowest tertile category of Western dietary pattern score (HR = 2.07, 95% CI = 1.03-4.18, P for trend = 0.01). Traditional dietary pattern was not associated with incidence of CVD or CVD risk factors. A significant association was observed between the Western dietary pattern and changes in serum insulin (β = 5.88, 95% CI = 0.34-11.4). Our findings confirm that the Western dietary pattern, characterized by higher loads of processed meats, salty snacks, sweets, and soft drinks, is a dietary risk factor for CVD in the Iranian population.

Antimullerian hormone and its receptor gene expression in prenatally androgenized female rats

BACKGROUND

Anti-mullerian hormone (AMH) levels reflect the number of small antral follicles in ovaries and expression changes of AMH and its receptor are suspected to be involved in the pathogenesis of polycystic ovary syndrome (PCOS).

OBJECTIVES

The aim of this study was to evaluate gene expression of AMH and its receptor in immature and adult rats prenatally exposed to androgen excess.

MATERIALS AND METHODS

Six pregnant Wistar rats in the experimental group were treated by subcutaneous injection of 5 mg free testosterone on day 20 of pregnancy, while controls (n = 6) received only 500 mL of solvent. Female pups of each mother were randomly divided into three groups as day 0 (newborn), 10-day old and days 75-85 (adult). RNAs were extracted from ovarian tissues and relative expression levels for AMH and its receptor genes were measured using TaqMan Real-Time PCR. Serum AMH and testosterone levels were measured using ELISA method.

RESULTS

Relative AMH expression decreased in newborns, 10-day olds and adults (0.806, 0.443 and 0.809 fold, respectively). AMHR expression was higher in newborns and adults (1.432 and 1.057 fold, respectively), while it decreased by 0.263 fold in 10-day olds, although none of them were significant (P > 0.05). In addition, AMH levels were consistent with the results of gene expression. Testosterone hormone levels from 10 day-olds to adults were significantly increased in both study groups (P = 0.016).

CONCLUSIONS

While AMH receptor expression was higher in experimental rats, their serum concentrations of AMH were decreased. Further researches with greater sample sizes and measurement of bioactive forms of hormones are recommended to confirm the findings of this study.