Effects of acylcarnitines on fatty acid oxidation in primary human skeletal muscle cells as well as soleus, extensor digitorum longus, tibialis and quadriceps muscles from mice.

<p>Oxidation of ³H-palmitate determined after 4 h in human myotubes in the presence of L-carnitine (L-C), acetylcarnitine (ActC), an equimolar mixture of C8:0-, C10:0- and C12:0-acylcarnitine (AC), or C8:0-(C8-AC), C10:0- (C10-AC) and C12:0-acylcarnitine (C12-AC) as indicated (A,B). Values of ³H-palmitate oxidation of control cells were set as 1. (C) Palmitate oxidation in the presence of 50 µM L-carnitine and 1, 5, 10 or 100 µM AC. Values of ³H-palmitate oxidation of cells solely incubated with 50 µM L-carnitine were set as 1; shown are means ± SEM from 4 independent experiments, * p<0.05 vs. L-carnitine; # p<0.05 vs acetyl-carnitine; † p<0.05 vs. C8-AC or C10-AC, respectively. (D) Oxidation of ³H-palmitate in mouse soleus, extensor digitorum longus (EDL), tibialis (tib) or quadriceps (Q) muscle from three different mice determined after 90 min in the presence of an equimolar mixture of C8:0-, C10:0- and C12:0-acylcarnitine as indicated. Shown are means ± SEM, values of ³H-palmitate oxidation in untreated tissues were set as 1, * p<0.05 vs. untreated tissues.