Reassessing triglyceride synthesis in adipose tissue

The synthesis and breakdown of triglycerides in adipose tissue and muscle is a crucial element of energy metabolism because it ensures that adequate fuel is available during starvation. Triglyceride turnover determines the availability of fatty acids for utilization by mammalian tissues, and any dysfunction in this process can lead to alterations in glucose metabolism, insulin resistance and type 2 diabetes. Our understanding of the reactions involved in triglyceride synthesis is currently being reassessed, primarily because of the recently identified role that re-esterification of fatty acids plays in triglyceride deposition and, thus, in controlling fatty-acid availability. Here, we review recent information on triglyceride synthesis and introduce the pathway of glyceroneogenesis as an important and highly regulated source of glyceride-glycerol in adipose tissue.