The Effect of Zinc-Selenium Green Tea(<i>Camellia sinensis</i>) on Thyroid Functionin Male Rats After Long-TermExposure to Nonylphenol

The aim of this work was to determine whether chronic exposure to nonylphenol (NP) at environmental concentration would have toxic effects on thyroid function and thyroid hyperplasia disease and whether zinc-selenium green tea has a protective effect on thyroid damage induced by NP in male rats.B-ultrasound revealed that there were thyroid nodules in both the zinc-selenium green tea group and the NP group.The group exposed to NP showed irregular follicle shapes, an increased number of small follicles, and increased follicular epithelial thickness.The epithelial thickness of the tea groups was significantly lower than that of the NP group (H = 38.85,P≤0.001).Exposure to NP could induce the increased protein levels of ERα, ERβ, TRα, and TRβ in thyroid tissues.The expression of ERα (F = 20.75,P≤0.001), ERβ (F = 32.32,P≤0.001), TRα (F = 13.81,P≤0.001), and TRβ (F = 13.92,P≤0.001) proteins in the zinc-selenium green tea group was decreased compared with that in the NP group.Chronic NP exposure could cause pathological damage to the thyroid tissue.Zinc selenium tea could provide protective effects for the thyroid damage caused by NP.