PRMT4 promotes ferroptosis to aggravate doxorubicin-induced cardiomyopathy via inhibition of the Nrf2/GPX4 pathway

Doxorubicin (DOX), a commonly used antitumor agent, is often accompanied by its dosage-dependent cardiotoxicity, which incorporates ferroptosis in its pathogenesis. Protein arginine methyltransferase 4 (PRMT4) is a transcription regulator involved in the modulation of oxidative stress and autophagy, but its role in DOX-induced cardiomyopathy (DIC) and ferroptosis remains elusive. Herein, we aimed to investigate the involvement and the underlying mechanisms of PRMT4 in the pathogenesis of DIC. Our present study revealed that the expression level of PRMT4 was markedly decreased in DOX-treated cardiomyocytes. Interestingly, it is noted that PRMT4 overexpression accelerated ferroptosis to aggravate DIC, while its gene disruption or pharmaceutical inhibition exhibited the opposite effect. Mechanistically, our observation demonstrated that PRMT4 interacted with the nuclear factor erythroid 2-related factor 2 (Nrf2) to promote its enzymatic methylation, which restricted the nuclear translocation of Nrf2 and subsequently suppressed the transcription of glutathione peroxidase 4 (GPX4). Importantly, the detrimental role of PRMT4 in DOX-induced cardiomyocyte ferroptosis was abolished by Nrf2 activation or Fer-1 administration. Collectively, our data reveal that PRMT4 inhibits Nrf2/GPX4 signaling to accelerate ferroptosis in DIC, suggesting that targeting PRMT4 may present as a potential preventive strategy against the development of DIC.