Effect of bisphenol S and bisphenol A on morphometric and hormonal changes of thyroid gland and iodine concentration in urine of Wistar rats /Efekt Bisfenolu S a Bisfenolu A na morfometricke parametry stitne zlazy, zmeny hormonu a koncentrace jodu v moci potkanu Wistar

Bisphenol S (BPS) is the major substitute of the endocrine disruptor bisphenol A (BPA). Due to the presence of strong double bonds, BPS is more resistant to biodegradation and therefore more BPS remains in the environment. Numerous studies show that BPS disrupts the reproductive, nervous, and cardiovascular systems and could have an impact on thyroid hormones. The study aimed to analyze the effects of a 10-week exposition of BPS and BPA on lipid markers, morphometric parameters of the rat thyroid gland, the thyroid stimulating hormone (TSH) levels and the influence of BPS on urine iodine concentration. Male Wistar rats received BPS in sunflower oil daily by gavage. The control group (GI) received only the vehicle. The BPS experimental group two (GII) received 4 ug/kg/day, group three (GIII) received 50 ug/kg/day, and group four (GIV) received 100 mg BPS/kg/day. Group five (GV) received 100 mg BPA/kg/day. Groups four and five were made to compare the influence of high concentration between BPS and BPA. Results show the influence of BPS and BPA on body weight, triacylglycerols, cholesterol and total protein concentration. Morphometric changes in the size of thyroid gland follicles show a bigger influence of BPS than BPA. Results show also increasing in TSH concentrations in all groups with bisphenols up to physiology standards of Wistar rats (GI 3.14 [+ or -] 1.28 ng/ml, GII 5.12 [+ or -] 1.16 ng/ml, GIII 5.55 [+ or -] 2.39 ng/ml, GIV 5.56 [+ or -] 1.98 ng/ml, GV 4.47 [+ or -] 1.09 ng/ml) and influence of BPA and BPS on higher iodine concentrations in urine.