Plasmalogens

Plasmalogens are glycerophospholipids (ether lipids) which are structurally similar to phosphatidylcholine or phosphattidylethanolamine. However, instead of a fatty acid, a fatty acid aldehyde is bound to the C1 atom of glycerol as enol ether. The 2nd fatty acid, bound as an ester, is usually polyunsaturated.

Plasmalogens represent up to 20% of the total phospholipid mass of humans. They are key structural phospholipids in the brain membranes (Braverman).

In the brain and serum of patients with Alzheimer's disease, plasmalogens are reduced (Wood PL et al. 2010).

Furthermore, a plasmalogen deficiency is characteristic of Zellweger syndrome and chondrodysplasia punctata (Braverman). In this syndrome mutations of the genes coding for peroxisomes (PEX-1, PEX-5) are present. This mutation leads to a severe enzyme deficiency in the peroxisomes. As a result, plasmalogens can no longer be synthesized.

1. Braverman NE et al (2012) Functions of plasmalogen lipids in health and disease. Biochim Biophys Acta 1822:1442-2452.
2. Wood PL et al (2010) Circulating plasmalogen levels and Alzheimer Disease Assessment Scale-Cognitive scores in Alzheimer patients. J Psychiatry Neurosci 35:59-62.