Nrf2 Deficiency Exaggerates Doxorubicin-Induced Cardiotoxicity and Cardiac Dysfunction
Figure 6
Effects of Nrf2 overexpression and knockdown on Dox-induced impairment of autophagy in cardiomyocytes. (a) Dox-induced impairment of autophagic flux. Rat neonatal cardiomyocytes were treated with Dox (1 μM) in serum-free DMEM for 24 h and bafilomycin A1 (BafA1, 5 nM) was added during the last 4 h. Left panel: representative immunoblots of Dox-induced LC3-II expression with or without BafA1 treatment. Middle panel: quantified densitometric analysis of Dox-induced LC3-II expression. , versus vehicle control (−). Right panel: representatives of immunoblots of Dox-induced accumulation of ubiquitinated proteins in soluble (Sol) and insoluble (Insol) fractions. Cells were treated with or without Dox (1 μM) for 24 h. (b) Overexpression of Nrf2 on Dox-induced LC3-II expression and accumulation of ubiquitinated proteins in rat neonatal cardiomyocytes. Infected cells were subjected to Western blot analysis of LC3 and insoluble (Insol) ubiquitinated protein levels. Cells were treated with Dox (1 μM) for 24 h. , versus Ad-Gfp (−). Inserted blots: confirming the infection efficiency of Ad-Nrf2. (c) Overexpression of miNrf2 on Dox-induced LC3-II expression and accumulation of ubiquitinated proteins in rat neonatal cardiomyocytes. Infected cells were subjected to Western blot analysis of LC3 and insoluble (Insol) ubiquitinated protein levels. Cells were treated with Dox (1 μM) for 24 h. , versus Ad-Scramble (−). Inserted blots: confirming the infection efficiency of Ad-Nrf2.
