Metabolism of dolichol, dolichoic acid and nordolichoic acid in cultured cells

Abstract The uptake and metabolism of [1- 14 C]-labelled dolichol, dolichoic acid and nordolichoic acid were investigated in MDCK and HepG2 cells. Each of the three isoprenoids, bound to human serum albumin, was taken up effectively. None of the compounds was broken down in HepG2 cells, although these converted dolichol into fatty acid esters. In MDCK cells dolichoic acid gave rise to the formation of [ 14 C]CO 2 and radiolabelled formic acid, indicating that dolichoic acid can be broken down by α -oxidation. Dolichoic acid was also converted to a mixture of polar compounds, possibly polyols. MDCK cells generated radiolabelled CO 2 from nordolichoic acid, presumably through β -oxidation, although we could not find any labelled propionic acid. No oxidative breakdown of dolichol was found, apparently due to the lack of or very low conversion to dolichoic acid.