COPD-Like Phenotypes in TBC-Treated Mice Can be Effectively Alleviated via Estrogen Supplement.

Tris(2,3-dibromopropyl) isocyanurate (TBC), recognized as an endocrine disruptor, can cause inflammatory injury to the lung tissue of mice. To investigate the specific respiratory effects of TBC, male C57BL/6J mice were administered a daily dose of 20 mg/kg of TBC over 14 days. Postexposure, these mice developed chronic obstructive pulmonary disease (COPD)-like symptoms characterized by inflammatory lung damage and functional impairment. In light of the antiestrogenic properties of TBC, we administrated estradiol (E2) to investigate its potential protective role against TBC-induced damage and found that the coexposure of E2 notably mitigated the COPD-like phenotypes. Immunohistochemical analysis revealed that TBC exposure reduced estrogen receptor alpha (ERα) expression and increased nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression, while E2 treatment rebalanced the expression levels of ERα and NF-κB to their normative states. Our findings indicate that TBC, as an antiestrogenic agent, may contribute to the pathogenesis of COPD through an ERα-mediated inflammatory pathway, but that E2 treatment could reverse the impairment, providing a potentially promising remedial treatment. Given the lung status as a primary target of air pollution, the presence of antiestrogenic compounds like TBC in atmospheric particulates presents a significant concern, with the potential to exacerbate respiratory conditions such as COPD and pneumonia.