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Effect of Subclinical and Overt Form of Rat Maternal Hypothyroidism on Offspring Endochondral Bone Formation. ACTA VET-BEOGRAD 2018. [DOI: 10.2478/acve-2018-0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Abstract
Maternal hypothyroidism in its overt form affects skeletal development of the offspring, but these data are not available for the subclinical form which is becoming very frequent among pregnant women. We hypothesized that the subclinical form of hypothyroidism in rat dams, infl uences the process of offspring endochondral ossifi cation affecting proliferation and differentiation of chondrocytes, osteoclasts and osteoblasts in pups. Seven-day-old male pups (n=18) derived from control dams and dams treated with a low dose (1.5 mg/L) or high dose (150 mg/L) of propylthiouracil in drinking water during pregnancy and lactation were used. Histomorphometric analysis of pups’ tibia proximal growth plate, expression of mRNA, immunohistochemical and histochemical visualization of extracellular matrix components was performed. The length of the tibia was reduced in hypothyroid pups. Secretion of type 2 and 10 collagens in the subclinical and overt form were lower while the amount of glycosaminoglycans was higher when compared with controls. Down-regulated tartrate resistant acid phosphatase mRNA indicated altered osteoclasts function while lower expression of dentin matrix acid protein-1 mRNA and reduced synthesis of type 1 collagen accentuated a compromised bone formation in the overt form of hypothyroidism. The subclinical form of maternal hypothyroidism had a negative effect on the differentiation of hypertrophic chondrocytes and calcifi ed cartilage removal in 7-day-old pups. In addition, overt hypothyroidism had a negative effect on the proliferation of chondrocytes and deposition of osteoid. Both forms of hypothyroidism resulted in a decrease of tibia length due to changes in growth plate formation.
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Danilović Luković J, Korać A, Milošević I, Lužajić T, Milanović Z, Kovačević Filipović M, Radovanović A. Z-cells and oogonia/oocytes in the advanced process of autophagy are the dominant altered cells in the ovaries of hypothyroid newborn rats. ACTA VET-BEOGRAD 2017. [DOI: 10.1515/acve-2017-0009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Abstract
Induced prenatal hypothyroidism in rat pups leads to accelerated primordial follicle assembly and premature follicular atresia with ovary failure. This work investigates the influence of maternal hypothyroidism induced with 6-n-propyl-2-thyouracil (PTU) on the number and morphology of oogonia/oocytes in newborn rat pups with light and transmission electron microscopy. Expression of apoptosis and autophagy markers in oogonia/oocytes were examined using immunohistochemistry. Hypothyroid newborn pups had a decreased number of mitotic and resting oogonia, while the number of altered oogonia/oocytes was increased. Ultrastructural observations revealed the increased presence of degenerated pachytene oocytes (Z-cells) and oogonia/oocytes undergoing autophagy, apoptosis and combined apoptosis and autophagy, in this group. The most abundant altered oogonia/oocytes in the hypothyroid group were those with morphological features of advanced autophagy and Z-cells. The percentage of TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) positive oogonia/oocytes was significantly lower in the hypothyroid group. No significant difference was recorded in the expression of caspase-3, ATG7 and LC3 possibly reflecting that these proteins were not involved in the oogonia/oocyte alteration process during prenatal rat hypothyroidism. The obtained results indicate that developmental hypothyroidism in the offspring enhances the number of Z-cells and oogonia/oocytes altered with the advanced process of autophagy.
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Affiliation(s)
- Jelena Danilović Luković
- State University of Novi Pazar, Department of Biomedical Sciences, Vuka Karadžića bb, 36300 Novi Pazar, Serbia
| | - Aleksandra Korać
- University of Belgrade, Center for Electron Microscopy, Faculty of Biology, Studentski trg 16, 11000 Belgrade, Serbia
| | - Ivan Milošević
- University of Belgrade, Faculty of Veterinary Medicine, Bulevar oslobođenja 18, 11000 Belgrade, Serbia
| | - Tijana Lužajić
- University of Belgrade, Faculty of Veterinary Medicine, Bulevar oslobođenja 18, 11000 Belgrade, Serbia
| | - Zorana Milanović
- University of Belgrade, Faculty of Veterinary Medicine, Bulevar oslobođenja 18, 11000 Belgrade, Serbia
| | | | - Anita Radovanović
- University of Belgrade, Faculty of Veterinary Medicine, Bulevar oslobođenja 18, 11000 Belgrade, Serbia
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