The role of fatty acid oxidation in the epidermis

Using cultured epidermal cells from guinea pig ears, we have determined that the epidermis has a consistenly low respiratory quotient which is indicative of lipid metabolism. When the tissue was supplied with an exogenous source of free fatty acid, the rate of oxidation was quite large. Inhibition of fatty acid oxidation by alpha-bromopalmitate, an inhibitor of fatty acid oxidation in other mammalian cells, was associated with a decrease in both the rate of respiration and a decrease in the total pool of adenosine triphosphate (ATP). These data indicate that alpha-bromopalmitate, through its inhibtory effect on fatty acid oxidation, decreases the amount of substrate entering the tricarboxylic acid cycle which in turn decreases the rate of both oxygen uptake and ATP production. A consequence of this lowered ATP level is a decreased rat of DNA synthesis, an effect which may be beneficial in controlling hyperproliferative diseases of the skin.