Fig. 7
From: Activation of the Keap1/Nrf2 stress response pathway in autophagic vacuolar myopathies
CQ-induced autophagy inhibition leads to Nrf2 pathway activation in C2C12 muscle cells. a. Treatment of differentiated C2C12 myotubes with autophagy inhibitor CQ increased the sarcoplasmic level of LC3-II and SQSTM1 proteins in a dose- and time-dependent manner, indicating effective inhibition of the autophagic flux. Autophagy inhibition was accompanied by a slight decrease in the sarcoplasmic level of the soluble Keap1 protein (possibly reflecting its sequestration into insoluble protein aggregates) and an increase in the nuclear level of Nrf2 protein. GAPDH and lamin B were used as loading controls for sarcoplasmic and nuclear protein-enriched fractions, respectively; a representative of 3 independent experiments is shown. b. Treatment of C2C12 myotubes with 15 μM CQ for 24 h led to a statistically significant increase in mRNA levels of the Nrf2-regulated genes Nqo1, Hmox1, Gsr, G6pd, and Gclm (but not Gclc). (mean ± SEM; *, p < 0.05; **, p < 0.01; n = 5-8, unpaired t-test)