The Potential Effect of Simvastatin on Regulatory T cells in Experimentally Induced Autoimmune Thyroiditis in Female Rats


  • Yaqeen Talib Mohammed Department of Pharmacology and Toxicology, College of Pharmacy, University of Mustansiriyah, Iraq
  • Nadia Hameed Mohammed Department of Microbiology and Immunology, College of Medicine, University of Mustansiriyah, Iraq
  • Inam Sameh Arif Department of Microbiology and Immunology, College of Medicine, University of Mustansiriyah, Iraq



Autoimmune thyroiditis; Hashimoto’s Thyroiditis; Statins; pleotropic effects; simvastatin; Tregs; TGF-ß


Autoimmune thyroiditis also named Hashimoto's thyroiditis: is an inflammatory disorder of the thyroid gland. It is characterized by circulating antibodies to thyroid antigens, and enlargement of the gland with lymphocytic infiltration.

Regulatory T cells (Tregs), a particular subset of CD4+ T cells that express CD25 at a markedly increased level. they can regulate immune response in order to preserve homeostasis and self-tolerance. T cell expansion and cytokine production are restricted by Tregs. The development of this autoimmune disease is influenced by TGF-ß1 shortage. Management of HT is usually a symptomatic therapy that concentrates on HT's symptoms rather than its underlying cause. Statins, the lipid lowering medications have pleotropic effects. they can alter immunological reactions. Twenty-four female rats were used for this experiment divided into four groups (n=6), the disease was induced in all groups except group1 (control) where rats only received phosphate buffer saline, group 2 (induction group), group 3 received Prednisolone 2mg\kg orally for 30 days and group 4 received Simvastatin (4mg\kg) orally for 30 days too. Hashimoto’s thyroiditis was induced experimentally by subcutaneous injection of porcine thyroglobulin in Freund’s adjuvant emulsion (4mg/ml). Results showed an increase in Tregs and serum TGF-ß level in rats treated with simvastatin.

In conclusion, simvastatin improves the number of functioning Tregs and increases TGF-ß signaling to suppress the autoimmune reaction. Therefore, simvastatin can be a promising approach in the treatment of this disease.


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How to Cite

Yaqeen Talib Mohammed, Nadia Hameed Mohammed, & Inam Sameh Arif. (2023). The Potential Effect of Simvastatin on Regulatory T cells in Experimentally Induced Autoimmune Thyroiditis in Female Rats. Al Mustansiriyah Journal of Pharmaceutical Sciences, 23(4), 443–453.

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