Cellular fatty acid uptake: the contribution of metabolism : Current Opinion in Lipidology (original) (raw)

Lipid metabolism

Department of Nutrition, University of North Carolina, Chapel Hill, NC 27599, USA

Correspondence to Rosalind A. Coleman MD, University of North Carolina at Chapel Hill, School of Public Health, 2301 Michael Hooker Research Center, CB#7461, Chapel Hill, NC 27599-7461, USA Tel: +1 919 966 7213; fax: +1 919 843 8555; e-mail: [email protected]

Sponsorship: This work was supported by grants from the National Institutes of Health, DK56598, DK59935, and DK68993.

Abstract

Purpose of review

The aim of this review is to highlight the importance of fatty acid metabolism as a major determinant in fatty acid uptake. In particular, we emphasize how the activation, intracellular transport and downstream metabolism of fatty acids influence their uptake into cells.

Recent findings

Studies examining fatty acid entry into cells have focused primarily on the roles of plasma membrane proteins or the question of passive diffusion. Recent studies, however, strongly suggest that a driving force governing fatty acid uptake is the metabolic demand for fatty acids. Both gain and loss-of-function experiments indicate that fatty acid uptake can be modulated by activation at both the plasma membrane and internal sites, by intracellular fatty acid binding proteins, and by enzymes in synthetic or degradative metabolic pathways. Although the mechanism is not known, it appears that converting fatty acids to acyl-CoAs and downstream metabolic intermediates increases cellular fatty acid uptake, probably by limiting efflux.

Summary

Altered fatty acid metabolism and the accumulation of triacylglycerol and lipid metabolites has been strongly associated with insulin resistance and diabetes, but we do not fully understand how the entry of fatty acids into cells is regulated. Future studies of cellular fatty acid uptake should consider the influence of fatty acid metabolism and the possible interactions between fatty acid metabolism or metabolites and fatty acid transport proteins.