Fatty aldehyde dehydrogenase, the enzyme downstream of tetrahydrobiopterin-dependent alkylglycerol monooxygenase

Abstract

The tetrahydrobiopterin-dependent degradation of ether lipids by alkylglycerol monooxygenase (AGMO) produces fatty aldehydes, which are toxic to cells. Therefore, it is of great physiological importance that these harmful compounds are converted into their corresponding, less toxic fatty acids by fatty aldehyde dehydrogenase (FALDH). Dysfunction of this enzyme causes Sjögren-Larsson syndrome. This severe inherited disorder is accompanied by symptoms such as ichthyosis, mental retardation and spasticity. Surprisingly, fatty alcohols and not fatty aldehydes were found to accumulate in fibroblasts of Sjögren-Larsson syndrome patients, suggesting that there can be wide-ranging alterations in the lipid composition of patient cells. In particular, this has to be considered when searching for possible treatment options for patients suffering from Sjögren-Larsson syndrome. For example, inhibition of fatty aldehyde producing ether lipid degradation would have multiple implications on ether lipid- and fatty alcohol-mediated signalling pathways.

Keywords

• alkylglycerol monooxygenase
• fatty aldehyde dehydrogenase
• sjögren-larsson syndrome
• sphingosine-1-phosphate
• tetrahydrobiopterin
• enzymes: alkylglycerol monooxygenase (e.c. 1.14.16.5); fatty aldehyde dehydrogenase (long-chain aldehyde dehydrogenase, e.c. 1.2.1.48); lysoplasmalogenase (alkenylglycerophosphocholine hydrolase, e.c. 3.3.2.2); lysoplasmalogenase (alkenylglycerophosphoethanolamine hydrolase, e.c. 3.3.2.5); sphingosine-1-phosphate lyase (sphinganine-1-phosphate aldolase, e.c. 4.1.2.27)