Figure 8From: Integrated analysis of chronic lipotoxicity on muscle metabolism and stress and its reversal by antioxidantsScavenging oxidative stress protects myotubes from lipotoxicity. Myotubes were cultured under control or lipotoxic conditions or lipotoxic conditions containing N-acetyl cysteine (NAC). NAC, a ROS scavenger, reduced lipotoxicity induced ROS levels in myotubes (A, *** P < 0.001). (B) Stress signaling as measured by JNK phosphorylation and ER stress as measured by CHOP levels were reduced by NAC. (C) This antioxidant also reduced IMTG levels (*** P < 0.001; ** P < 0.01) and increased mitochondrial DNA copy number (D, * P < 0.05). Expression of PGC1α (E), MEF2C (F) and CPT1β (G) genes was found to be increased by NAC (* P < 0.05, ** P < 0.01, *** P < 0.001). NAC treatment also increased cellular viability (H, *** P < 0.001; * P < 0.05) and ATP levels (I, ** P < 0.01). (J) Lipotoxic conditions decreased and NAC treatment restored SDH activity (*** P < 0.001). (K) Insulin stimulated glucose uptake was decreased under lipotoxic conditions and was restored by NAC treatment (* P < 0.05). ANOVA with Newman-Keuls post test was performed for statistical analyses.Back to article page