Biological Activity of Phytoestrogens

Subcutaneous administration of β-sitosterol, isolated from Glycyrrhiza glabra, into ovariectomized mice induced: — 1) An increase in the epithelial cell height of the thyroid vesicles, as well as a decrease in the surface area of the vesicular colloid when both were compared with the ovariectomized controls. 2) A stimulation of iodine uptake by the thyroid glands of treated animals. Phytoestrogen treatment showed no linear relationship between the dosage of β-sitosterol and the thyroid uptake of I 3) A rise in the level of thyroid and thyrotrophic hormones in the blood of mice injected with β-sitosterol. This increase in hormone levels parallels the thyroid activity.