ACTA ENDOCRINOLOGICA (BUC)

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune polymorphous disease that primarily affects women of reproductive age. This gender disparity has suggested the importance of investigating the role of reproductive hormones in the pathogenesis of the disease. Estradiol, the most potent form of estrogen, plays a key role in shaping the immune system including the production of lymphocytes, the peripheral differentiation of regulatory T cells (T-regs), antibody production, and the complement and interferon systems, and has been studied in the pathogenesis of systemic lupus erythematosus (SLE). It operates by binding to estrogen receptors (ERs) α and β, initiating cellular responses including alterations in gene expression. Regulatory T cells are instrumental in preserving immunological self-tolerance and moderating immune responses. Estradiol’s serum levels correlate with the expansion of CD4+CD25+ and FoxP3+ in healthy females. However, this response is reduced in lupus patients. Estradiol also interacts with microRNAs (miRNAs) in gene regulation. Hsa-miR-10b-5p, a miRNA targeting SRSF1, is overexpressed in SLE patients and its levels increase with exposure to estrogens. Other miRNAs also show correlation with plasma Estradiol levels. The precise role of Estradiol in the pathogenesis of SLE remains complex and multifaceted and is a topic for further research.

The aim of the study was to evaluate the prevalence of hyperhomocysteinemia in hypothyroid patients and the effect of folic acid supplementation when serum homocysteine\r\n(Hcy) was over risk level.\r\nPatients and methods. Patients with moderate (Group1) and severe hypothyroidism (Group 2) were evaluated before any therapy and after 6 months of combined folic acid and\r\nlevothyroxine substitution, versus control subjects. Hcy, folic acid, thyroid hormones and lipids were measured for all subjects. Thyroglobulin and antithyroglobulin antibodies were measured only for Group 2.\r\nResults. Only 17 % of the cases had basal Hcy at non risk level (<10 mmol/L). Both groups had higher Hcy levels than control (p <0.0001). In Group 1 basal folic acid was lower\r\nthan in control and group 2 (p<0.001). No correlation was found between high levels of Hcy (> 12 mmol/L ) and positive thyroglobulin. After 3 months of combined therapy, significant decrease of Hcy (p<0.0001) was observed compared with the basal level. Normalization of\r\nHcy appears during next 3 months even with reducing the folic acid supplementation.\r\nConclusion. Our results report moderate hyperhomocysteinemia in hypothyroid patients. This may exacerbate the cardiovascular risk traditionally attributed to lipid changes. Six months of combined therapy (L-thyroxine and folic acid) corrected hyperhomocysteinemia excluding the additional risk.