Betaine Enhances Skeletal Muscle Cell Lipid Accumulation By Promoting Adipogenic Genes Expression

Meat quality and the value of meat are dependent on intramuscular fat to a great extent. Therefore, enhancing intramuscular fat accumulation is particularly important. Betaine is a widely used feed additive and appears to increase intramuscular fat in growing pigs. However, the underlying regulatory mechanism of betaine on intramuscular fat deposition remains elusive. Here, we demonstrated that betaine enhanced C2C12 cellular lipid accumulation through regulating the expression of lipid metabolism related genes. We found 10mM betaine treatment significantly upregulated lipid content in C2C12 after adipogenic differentiation. Next we found that after 24h treatment betaine could markedly enhance C2C12 cellular lipid accumulation, other than 12h or 48h. Subsequently, we analysed the expression of lipid metabolism related genes by using RT-PCR. Our results showed that betaine treatment promoted adipogenic genes PPARγ, aP2 and LPL expression. Meanwhile, betaine did not affect the expression of lipidolytic genes ATGL and HSL as well as fatty acid transportation related genes FAbp3 and CD36. We also observed betaine enhanced mitochondrial function by upregulating PGC1α and PGC1β expression. Together, these results suggest that betaine enhances skeletal muscle cell lipid accumulation mainly through modulating adipogenic genes PPARγ, aP2 and LPL expression, which sheds light on the effect of betaine on intramuscular fat accumulation.