1Department of Clinical Nutrition， Daping Hospital， Army Medical University， Chongqing 400042， China; 2No.75220 Force， Chinese People’s Liberation Army， Huizhou 516133， Guangdong， China; 3Institute of Hepatopancreatobiliary Surgery， Southwest Hospital， Army Medical University， Chongqing 400042， China
Abstract：Objective To explore the underlying mechanisms of L-carnitine on improving cancer cachexia. Methods 100ng/ml TNF-α was used in murine myoblast cell-line C2C12 to induce cell atrophy. Cell model of cancer cachexia associated skeletal muscle loss was established. Differentiation status of skeletal muscle fiber treated by different doses of L-carnitine was observed under microscope after stained by crystal violet. Lipid metabolism related protein expressions in C2C12 were analyzed using Western Blot to explore the underlying mechanisms of L-carnitine on improving cancer cachexia. Results 100μg/ml and 1000μg/ml L-carnitine treatments induced differentiation of C2C12 and increased the diameter of skeletal muscle fiber (P<0.001). TNF-α group compared with the control group， the expression of CPT-I and PGC-1α decreased， while FOXO1， CD36 and PDK4 elevated. L-carnitine induced PGC1-α and CPT-I expressions but inhibited FOXO1 and CD36 expressions. L-carnitine had no effects on PDK4 expression. Conclusion L-carnitine improves cancer associated cachexia and increases skeletal muscle protein via regulating lipid metabolism capacity.
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