Thyroid Gland Alterations in Old-Aged Wistar Rats: A Comprehensive Stereological, Ultrastructural, Hormonal, and Gene Expression Study
2021
Authors:
Miler, MarkoAjdžanović, Vladimir
Živanović, Jasmina
Marković Filipović, Jelena
Šošić-Jurjević, Branka
Milošević, Verica
Document Type:
Article (Published version)
,
© 2021 by the author(s). Published by Cambridge University Press on behalf of the Microscopy Society of America.
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Show full item recordAbstract:
The aim of the present study was to determine and elaborate on all changes in old-aged (OA) versus young-aged (YA) rat thyroids by using
stereological, ultrastructural, hormonal, and gene expression analyses. We used 4- and 24-month-old male Wistar rats in our evaluation,
presenting all changes in comparison with YA rats. Results showed that the thyroid parenchyma was characterized by higher absolute
volumes of the gland, colloid, epithelium, and interstitium by 135, 135, 140, and 142% ( p < 0.05) respectively, while the relative volumes
of colloid and glands were unchanged. Ultrastructural analysis revealed less active glands, with smaller amounts of lysosomes, thyroglobulin
(Tg) granules, and microvilli in the luminal colloid. Optical density values for thyroid peroxidase (TPO), Tg, and vascular-endothelial
growth factor immunostaining remained unchanged; however, TPO and Tg exhibited visually stronger expression in small active follicles.
Thyroxine (T4)-Tg, the relative intensity of fluorescence (RIF), serum T4, and the sodium-iodide symporter immunohistochemical and gene
expressions decreased by 20, 40, 29, and 31% ( p < 0.05), respectively, in OA thyroids. Pituitary thyroid-stimulating hormone (TSH) RIF
increased by 44% ( p < 0.05), but the TSH serum concentration remained unchanged. In conclusion, the obtained results indicate depression
of the thyroid gland synthetic and secretory capacity with advanced age.
Keywords:
NIS; T4-Tg; Tg; TPO; TSHSource:
Microscopy and Microanalysis, 2021Funding / projects:
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200007 (University of Belgrade, Institute for Biological Research 'Siniša Stanković') (RS-MESTD-inst-2020-200007)
DOI: 10.1017/S1431927621000064
ISSN: 1431-9276
PubMed: 33586646
WoS: 000700414000021
Scopus: 2-s2.0-85100831764
URI
https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/abs/thyroid-gland-alterations-in-oldaged-wistar-rats-a-comprehensive-stereological-ultrastructural-hormonal-and-gene-expression-study/4C35B9A6AFED404C65272C08C8C2DC27https://radar.ibiss.bg.ac.rs/handle/123456789/4143