Maternal Subclinical and Clinical Hypothyroidism Effects on Rat Offspring: A Story of the Skin and its Derivatives

Epidermis stem cells have a crucial role through the processes of proliferation and differentiation, to replace cells that are constantly lost during tissue turnover or following injury. On the other hand, thyroid hormones regulate the proliferation and differentiation of epidermal cells and thus significantly influence the homeostasis of the skin. It is well known that maternal hypothyroidism during pregnancy leads to impaired development of many organ systems in their offspring. However, there is a lack of data about the influence of maternal subclinical hypothyroidism during pregnancy and lactation on the development of the skin and its derivatives in the litter. The aim of this study was to investigate the effects of maternal thyroid dysfunction on the development of the skin and its derivatives in their offspring in the early postnatal period. Antithyroid substance 6-n-propyl-2-thiouracil was added into the drinking water to female Albino Oxfords rats from the beginning of pregnancy and during lactation, with the aim to induce subclinical and overt form of hypothyroidism. Skin samples were taken from male pups within twenty-four hours and seven days after birth. The main findings of this investigation were that both forms of maternal hypothyroidism lead to serious damage of the epidermis in pups in terms of pronounced hyperkeratosis and reduction of the germinal layer along with a reduced number of hair follicles and their delayed morphogenesis. Epidermal impairments were more pronounced in pups with the overt form of hypothyroidism while offspring with the subclinical form had impairments that were less pronounced and delayed in occurrence.