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04:39
Generation of a Mouse Spontaneous Autoimmune Thyroiditis Model
Published on: March 17, 2023
Polychlorinated biphenyls affect thyroid function and induce autoimmunity in Sprague-Dawley rats
1Department of Endocrinology, First Affiliated Hospital, Nanjing Medical University, Nanjing, P. R. China.
Hormone and Metabolic Research = Hormon- Und Stoffwechselforschung = Hormones Et Metabolisme
|June 17, 2009
Summary
Polychlorinated biphenyls (PCBs) disrupt thyroid function by inducing an autoimmune response, unlike antithyroid drugs. This study reveals PCBs elevate thyroid peroxidase antibodies and cause distinct histopathological changes, indicating a unique mechanism of thyroid toxicity.
Area of Science:
- Environmental Toxicology
- Endocrinology
Background:
- Polychlorinated biphenyls (PCBs) are known environmental contaminants with diverse toxic effects.
- The impact of PCBs on thyroid function and the potential for autoimmune induction require further investigation.
Purpose of the Study:
- To assess thyroid function following PCB exposure.
- To determine if PCBs trigger autoimmune processes in the thyroid gland.
Main Methods:
- Sprague-Dawley rats were administered Aroclor 1,254 (PCBs) or propylthiouracil (PTU).
- Serum levels of thyroid hormones (FT3, FT4, T4), TSH, and TPOAb were measured.
- Thyroid histopathology was examined.
Main Results:
- PCBs and PTU significantly reduced FT3, FT4, and T4, and increased TSH.
- TPOAb levels were significantly elevated in the PCB group but not the PTU group.
- PCBs induced thyroid hyperplasia, reduced colloid, vascularization, and lymphocytic infiltration; PTU caused follicle shrinkage.
Conclusions:
- PCBs impair thyroid function through the induction of autoimmunity.
- This autoimmune mechanism differs from the direct effects of antithyroid drugs like PTU on the thyroid gland.
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