Effect of Lipid Structure on the Capacity of Myelin Basic Protein to Alter Vesicle Properties: Potent Effects of Aliphatic Aldehydes in Promoting Basic Protein‐Induced Vesicle Aggregation

Abstract

The capacity of myelin basic protein or of poly-L-lysine to promote leakage of carboxyfluorescein from vesicles or the aggregation of vesicles was studied. The vesicles were composed of phosphatidylcholine as the sole or major lipid component. Addition of 10% sphingomyelin, 10% phosphatidylglycerol, 10% egg or bovine brain phosphatidylethanolamine, or 30% dodecanal had relatively little effect on the extent of carboxyfluorescein release in the presence of either myelin basic protein or poly-L-lysine. In contrast with these results, the extent of vesicle aggregation was very sensitive to lipid composition. Addition of 10% phosphatidylglycerol induced more aggregation than the other phospholipids tested. Admixing 10% of a partially degraded sample of bovine brain phosphatidylethanolamine also led to a large amount of aggregation induced by the myelin basic protein. This latter aggregation appeared more specific for the basic protein, as it occurred to a much smaller extent with poly-L-lysine. In general, the effects of the myelin basic protein on either carboxyfluorescein release or vesicle aggregation were similar to, although somewhat greater than, that of poly-L-lysine. The aggregation of vesicles containing degradation products of phosphatidylethanolamine can be ascribed largely to the presence of aliphatic aldehydes. The effect of aliphatic aldehydes was specific in that the aliphatic alcohol, hexadecanol, or the short-chain aldehydes, acetaldehyde or butyraldehyde, did not promote myelin basic protein-induced vesicle aggregation. In addition, poly-L-lysine was less effective than the basic protein in aggregating vesicles containing aliphatic aldehydes. (ABSTRACT TRUNCATED AT 250 WORDS)

Plasmalogen deficiency in early Alzheimer's disease subjects and in animal models: molecular characterization using electrospray ionization mass spectrometry

“…This result is in agreement with the observation that the content of plasmalogen in human brain varies as a function of age; the maximum of the plasmalogen content is reached by an age of about 30 years (Rouser and Yamamoto 1968). Although the oxidative products of plasmalogen were known to induce vesicle aggregation (Epand et al 1984) and an oxidative burst reaction in stimulated neutrophils (Weisser et al 1997), their effects on the pathogenesis of AD remain to be further studied. In addition to oxidative damage, other enzymatic or non-enzymatic factors, which have been demonstrated to induce membrane defects, may also play an important role in causing a plasmalogen de®ciency (e.g.…”

“…This result is in agreement with the observation that the content of plasmalogen in human brain varies as a function of age; the maximum of the plasmalogen content is reached by an age of about 30 years (Rouser and Yamamoto 1968). Although the oxidative products of plasmalogen were known to induce vesicle aggregation (Epand et al . 1984) and an oxidative burst reaction in stimulated neutrophils (Weisser et al .…”

Salt-Triggered Intermembrane Exchange of Phospholipids and Hemifusion by Myelin Basic Protein

“…Myelin basic protein (MBP 1 ), a major cytoplasmic component of the myelinated cells of the central nervous system, is believed to be responsible for the tight association of the cytoplasmic surfaces in compact myelin (Boggs et al, 1982). MBP binds preferentially to anionic bilayer surfaces (Gould & London, 1972;Boggs et al, 1977) and promotes aggregation and increase in permeability of vesicles (Epand et al 1984;Papahadjopoulos et al, 1973). Since MBP has 24% hydrophobic and 19% positively charged residues at physiological pH, both electrostatic and hydrophobic interactions with the membrane are important (Boggs et al, 1980(Boggs et al, , 1982.…”

Genetics and prospective therapeutic targets for Sjögren-Larsson Syndrome

“…MBP has been shown to interact in vitro with artificial membrane vesicles containing hexadecanal. [69] A potential metabolic source of long-chain aldehydes in myelin includes plasmalogen forms of PE, which comprise up to 90% of the total phospholipids of myelin. [70] Long-chain aldehydes are produced during the enzymatic degradation of plasmalogens.…”