Background:In diabetes mellitus because of the absence or insufficient sensitivity to insulin, glucose transporter protein in cell membrane, glucose transporter 4, is decreased. GLUT4 is the major glucose transporter in skeletal muscle and adipose tissue, which is under control of insulin. It remains, however, unclear whether cinnamaldehyde plays a regulatory role(s) or not.Objectives:The objective of this study was to investigate the effects of cinnamaldehyde on GLUT4 gene expression.Materials and Methods:This study was an experimental trial. Tests were performed in triplicates. This study examined effects of cinnamaldehyde on Glut4 gene expression in C2C12 skeletal muscle cells by using Real Time PCR. C2C12 myoblasts were cultured in DMEM + 10 % FBS. After differentiation of myoblasts to myotubes, the cells were serum deprived for 5 hours and then treated with 10, 20, or 50 µM of cinnamaldehyde for 1 hour.Results:Our data revealed a significant increase in the expression of Glut4 in cinnamaldehyde treated cells. In addition, GLUT4 mRNA level was increased in a dose dependent manner. Analyses were performed using the SPSS 16 for Windows software. Differences between the groups were determined by one-way ANOVA.Conclusions:These results demonstrate that cinnamaldehyde up regulates the expression of mouse skeletal muscle GLUT4 gene expression.