@conference{
author = "Lužajić, Tijana and Milošević, Ivan and Danilović Luković, Jelena and Marković, Danica and Milošević, Sandra and Kovačević Filipović, Milica and Radovanovic, Anita",
year = "2017",
abstract = "Thyroid hormones (TH) play a pivotal role in the development of mammalian skin, and
are necessary for both the initiation and maintenance of hair growth. Adult hypothyroid rats
showed impaired epidermal proliferation, hair growth and wound healing. Stem cells (SCs)
located at the bulges of the hair follicles are responsible for hair cycling, and contribute to
the regeneration of the new epidermis after wounding. Therefore a reduction in the number or
function of bulge stem cells could be a cause of disturbed skin reepithelization and hair follicle
maintenance. We hypothesized that a decrease in TH during prenatal development would affect
the bulge stem cell population.
Subclinical hypothyroidism was induced with propylthiouracil through drinking water
in a dose of 1.5 mg/l in pregnant Albino Oxford rats, from the first day of gravidity and during
lactation. The control group was untreated. Five, seven-day-old pups were euthanized and
skin samples were taken from the dorsal part of their bodies. The number of hair follicles was
estimated on an area of 1mm2 of dermis. For the immunohistochemical study, proliferating cell
nuclear antigen (PCNA) (Santa Cruz Biotechnology) and NANOG (Thermo Scientific) antibodies
were used. The number of PCNA and NANOG positive cells was estimated on the area of 1mm2
of hair follicle.
The number of hair follicles was reduced and the expression of PCNA was decreased
in the cells of the inner and outer sheath of hair follicles in the hypothyroid pups compared to the
controls. They also had an increased number of NANOG positive bulge cells which we presume
are multipotent SCs.
Decreased expression of PCNA demonstrates low proliferation and increased
expression of NANOG, which may be explained in two ways: 1) the inhibited differentiation of
putative SCs and/or 2) the reduction of mobilization of these cells to the epidermis or sebaceous
gland. Our results confirm that the lack of TH influences the formation of hair follicles in early
infantile rat pups.",
publisher = "Faculty of Veterinary Medicine, University of Zagreb",
journal = "7th International Congress Veterinary science and proffesion, October 5th-7th 2017, Zagreb",
title = "Thyroid hormones affect the proliferation and/or mobilization of bulge stem cell population",
pages = "152-152",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2734"
}