Fig. 4

Potential effect of CLA to counteract expression of endoplasmic reticulum stress markers induced by palmitic acid in C2C12 myotubes. Fully differentiated myotubes were incubated at day 9 with a CLA mixture (20 μM) and/or palmitic acid (0.5 mM), in the absence or in the presence of insulin (100 nM) for 24 h in serum-free differentiation media. CLA mixture was an equimolar solution (50:50) of both active isomers trans-10, cis-12 and cis-9, trans-11 CLA. The ER stress markers analyzed are Atf3 (a), CHOP (b), Xbp1s (c), and Xbp1 (d). Data are expressed as mean ± SEM of three independent experiments (n = 4–5 data in each experiment). Mean values with unlike letters are significantly different (P < 0.05); ANOVA followed by LSD test