High triiodothyronine levels induce myocardial hypertrophy via BAFF overexpression

Autor: Guo‐Qing Li, Xiao‐Mei Liu, Bing‐Li Liu, Yi Zhong, Qing‐Wei Gu, Jing‐Jing Miao, Jie Wang, Shu Liu, Xiao‐Ming Mao
Rok vydání: 2022
Předmět:
Zdroj: Journal of cellular and molecular medicine. 26(16)
ISSN: 1582-4934
Popis: Activated B cells contribute to heart diseases, and inhibition of B-cell activating factor (BAFF) expression is an effective therapeutic target for heart diseases. Whether activated B cells participate in the development and progression of hyperthyroid heart disease, and what induces B cells activation in hyperthyroidism are unknown. The present study aimed to determine the roles of BAFF overexpression induced by high concentrations of triiodothyronine (T3) in the pathogenesis of hyperthyroid heart disease. Female C57BL/6J mice were subcutaneously injected with T3 for 6 weeks, and BAFF expression was inhibited using shRNA. Protein and mRNA expression of BAFF in mouse heart tissues evaluated via immunohistochemistry, western blotting and polymerase chain reaction (PCR). Proportions of B cells in mouse cardiac tissue lymphocytes were quantified via flow cytometry. Morphology and left ventricle function were assessed using pathological sections and echocardiography, respectively. Here, we demonstrate that compared with the control group, the proportion of myocardial B cells was larger in the T3 group; immunohistochemistry, western blotting and PCR analyses revealed increased protein and mRNA expression levels of TNF-α and BAFF in heart tissues of the T3 group. Compared with the normal controls group, in the T3 group, the diameter of myocardial cells and some echocardiographic values significantly increased and hypertrophy and structural disorder were noticeable. Our results revealed that elevated levels of circulating T3 can promote the expression of BAFF in myocardial cells and can lead to B-cell activation, an elevated inflammatory response and ventricular remodelling.
Databáze: OpenAIRE