Nrf2 overexpression attenuates TGF-β-induced EMT-like changes and ferroptosis-related stress in lung epithelial cells

Transforming growth factor-β (TGF-β) is a key mediator of epithelial responses associated with pulmonary fibrotic remodeling. This study examined how nuclear factor erythroid 2-related factor 2 (Nrf2) manipulation affects EMT-like responses and ferroptosis-related stress in TGF-β-treated lung epithelial cells.

A549 and BEAS-2B cells were treated with TGF-β. Fer-1 treatment and stable Nrf2 overexpression or knockdown were used to examine changes in EMT-associated and ferroptosis-related proteins. Additional measurements included CCK-8 absorbance, intracellular Fe²⁺, ROS, MDA, and Nrf2 localization.

TGF-β reduced E-cadherin and increased N-cadherin and vimentin in both cell lines. These changes coincided with higher Fe^2 +, ROS and MDA levels and altered abundance of ferroptosis-related proteins. Fer-1 partly attenuated the EMT-marker response. TGF-β also increased nuclear Nrf2. Nrf2 overexpression reduced iron accumulation, oxidative stress and several EMT-associated changes, whereas knockdown enhanced the changes in EMT-associated and ferroptosis-related proteins.

Nrf2 overexpression attenuated several EMT-associated and ferroptosis-related responses to TGF-β in cultured lung epithelial cells. The findings support a link between Nrf2-regulated redox responses and EMT-like changes, but do not establish that ferroptosis is required for these changes.