Effects of lycopene on skeletal muscle fiber type and high fat diet induced oxidative stress.
J Nutr Biochem. 2020 Oct 8:108523. Epub 2020 Oct 8. PMID: 33039582
Increasing studies report that many natural products can participate in formation of muscle fibers. This study aimed to investigate the effect of lycopene on skeletal muscle fiber type in vivo and in vitro. C2C12 myoblasts were used in vitro study, and the concentration of lycopene was 10μM; In vivo, eight weeks old male C57/BL6 mice were used and divided into four groups (n=8): 1) ND: normal-fat diet; 2) ND+Lyc: normal-fat diet mixed with 0.33% w/w lycopene; 3) HFD: high-fat diet; and 4) HFD+Lyc: high-fat diet mixed with 0.33% w/w lycopene. The mice tissue samples were collected after 8 weeks feeding. We found that lycopene supplementation enhanced the protein expression of slow-twitch fiber, succinate dehydrogenase, and malic dehydrogenase enzyme activities, whereas lycopene reduced the protein expression of fast-twitch fibers, lactate dehydrogenase, pyruvate kinase enzymeactivities. Moreover, lycopene can promote skeletal muscle triglyceride deposition, enhanced the mRNA expression of genes related to lipid synthesis, reduced the mRNA expression of genes related to lipolysis. And high fat diet induced dyslipidemia and oxidative stress were attenuated after lycopenesupplementation. Additionally, lycopene supplementation reduced the glycolytic reserve but enhanced mitochondrial ATP production in C2C12 cells. These results demonstrated that lycopene affects the activities of metabolic enzymes in muscle fibers, promotes the expression of slow-twitch fibers and enhanced mitochondrial respiratory capacity. We speculated that lycopene affects the muscle fiber type through aerobic oxidation, suggesting that lycopene exerts potential beneficial effects on skeletal muscle metabolism.