Endocrine Abstracts

Introduction and aims: TGF-β1 participates in the pathogenesis of autoimmune diseases e.g. diabetes, Hashimoto disease, autoimmune digestive system disorders. The aim of our study was to evaluate TGF-β1 levels during pregnancy and after childbirth in women who developed postpartum thyroiditis (PPT) in comparison to the healthy control group (CG) and women with positive anti-thyroid antibodies (ATA+) who did not develop PPT.

Material and method: 96 women were examined in 1st and 3rd trimester of pregnancy (T1, T3) and 3.6 months postpartum (3MPP, 6MPP): 47 ATA+ without Hashimoto disease (28 with PPT, 19 ATA+ without PPT) and 49 controls. We measured TGF-β1 (ELISA), TSH, FT3, FT4, ATG, ATPO with the clinical chemistry analyzer Architect Chemistry System, TRAbs (RIA), fasting glucose, OGTT (enzymatic method with hexokinaze) and HbA1c (HPLC). All women underwent thyroid USG.

Results: 28 ATA+ developed PPT. Median levels of TGF-β1 were highest in ATA+ who did not develop PPT but no significant differences were found between the levels in pregnancy and postpartum period. The lowest levels of TGF-β1 were observed in CG and also did not differ significantly between trimesters and postpartum period. Only in PPT group TGF-β1 levels increased significantly at 3MPP in comparison to T1 (T1=15.2±6.6 ng/ml vs 3MPP=18.4±9.3 ng/ml; P<0.01 after Bonferroni correction). Significantly higher TGF-β1 levels were observed at 3MPP between PPT and CG (P=0.02), in T1 and T3 between ATA+ without PPT and CG (P=0.049; P=0.017, respectively). We found significantly higher TGF-β1 levels between all ATA+ and CG in T3, 3MPP and 6MPP (P=0.012; P=0.015; P=0.034, respectively).

Conclusions: Our results may suggest that TGF-β1 plays an important role in the pathogenesis of PPT. Significantly higher TGF-β1 levels between ATA+ women and CG suggest that this cytokine may play a crucial role in autoimmune thyroid disorders. This is the second study on the role of TGF-β1 in PPT and it confirms that TGF-β1 increases in postpartum period in women with PPT.