Abstract:Stearoyl-CoA desaturase (SCD) is a key enzyme that catalyzes the saturated fatty acyl-CoAs to unsaturated fatty acyl-CoAs and several SCD isoforms were found in different tissues and organisms. SCD mRNA expression level can be regulated by many factors, such as high calorie diet, excise, and hormones. Regulation of expression and activity of SCD can alter the ratio of monosaturaed fatty acid (MUFA) to saturated fatty acid (SFA), which can regulate lipid metabolism and further affect cellular stress response and insulin sensitivity. Taken together, accumulated evidence suggests that SCD could be a therapeutic target of metabolic syndrome. Key words: stearoyl-CoA desaturase-1; lipid metabolism; cellular stress response; insulin sensitivity