The pathogenetic role of stress in the course of thyroid gland cellular renewal
prev
next
prev
next
Author(s)
Author(s)
The pathogenetic role of stress in the course of thyroid gland cellular renewal Evgenia Bessalova
The goal of the study was to identify the relationship between external stressors of different origin and the development of proliferative - apoptotic changes in the thyroid gland at the cellular-molecular level in the experiment, taking to account the gender.
The study were carried out on 40 white Wistar rats of 130-150 g. body weight. Immunohistochemical method was used to study the dynamics of proliferative thyrocytes index and the severity of apoptosis reactions in the cell population after the influence of alimentary and immobilization stress in males and females rats separately.
At the age of 3-3.5 months, the thyroid gland of the White rat had a low degree of differentiation due to the significant rate of the inter-follicular epithelium. This corresponds to the normal value of the age-related structure in small laboratory rodents and reflects ontogenetic patterns. The active growth and development of the organ is
reflected by Ki-67 marker of proliferation. Rats of the control group fed with normal diet, showed the level of Ki-67 expression onaverage 2.4% in females and 4.25% in males. In females rats, that were within a month on a special diet (alimentary stress), the level of Ki-67 increased up to 3.4%, but that value could be estimated as low. In males, on the contrary, the level of glandular epithelial cell proliferation decreased up to 2.75%. Animals exposed to immobilization stress within 7 days, had significant (p≤0.05) changes in Ki-67 expression with the opposite vector depending on gender. The expression of Ki-67 in stressed females reached on average 11.25%, which is 5 times
higher than the control. In males, on the contrary, its value fell up to 1.5%.In the group of animals with combined stress, females did not survive until the end of the experiment, and in males the Ki-67 index fell up to 1.3%.The determination of the apoptosis marker expression FAS-R on thyrocytes revealed certain regularities. Multiple
comparisons between groups of animals showed significant differences between the group of females exposed to stress and on a normal diet, from all groups, except for a similar group of males (by the Kraskel-Uollis method at a value of p≤0.05). Multivariative analysis ANOVA showed a high degree of influence (96.7%) of animal gender on the proliferation of glandular epithelium, as well as stress (54.28%).
There is a direct link between external stressors and the development of functional and organic compensatory changes in the thyroid gland, which indicates the leading pathogenetic role of adaptation syndrome in the development of organ pathology. Changes in Ki-proliferation index and CD- 95 or FAS-R in experimental animals significantly indicates the role of multiple stress in the development of thyroid disease.There is a sexual dimorphism of the studied parameters, which can cause different morbidity of males and females in the population under stress.
DOI: https://ysmu.am/v2/wp-content/uploads/2023/09/7.-Zima-NAMJ-Vol-13-No-2.pdf The New Armenian Medical Journal Vol.13 (2019), Nо 2 52-58
