Journal of Microbial & Biochemical Technology

Abstract

Bacterial Lipopolysaccharides Change Membrane Fluidity with Relevance to Phospholipid and Amyloid Beta Dynamics in Alzheimer's Disease

Ian James Martins

Bacterial lipopolysaccharides (LPS) and their increase in plasma in individuals in the developing world has become of major concern. LPS can transform cells by their rapid insertion into cell membranes that partition into cholesterol/sphingomyelin domains. LPS alter cell phospholipid dynamics associated with the recruitment of the Alzheimer’s disease amyloid beta (Aβ) peptide with the promotion of toxic Aβ oligomer formation. The common pattern of naturally occurring phospholipids such as1-palmitoyl-2-oleolyl-phosphatidylcholine in cells confers cells with the rapid transfer of Aβ and phospholipids. Phospholipids such as dipalmitoylphosphatidylcholine (DPPC), dimyristoylphosphatidylcholine (DMPC) and dioleoylphosphatidylcholine (DOPC) are poorly transported with delayed metabolism of Aβ oligomers. LPS can alter cells with POPC cell membrane characteristics by insertion of itself and promotion of ganglioside GM1-cholesterol as the seed for Aβ oligomerization. LPS modification of cell membrane fluidity in neurons involves the phospholipid transfer protein that affects vitamin E, phospholipid and Aβ metabolism. Healthy diets that contain olive oil, canola oil and vegetable oil promote membrane fluidity and Aβ metabolism but in the developing world increased LPS levels interfere with healthy diets and their regulation of phospholipid and Aβ dynamics. Unhealthy diets that contain palmitic acid should be avoided that promote DPPC cell membrane contents with poor phospholipid and Aβ metabolism. Nutritional therapy may improve metabolic disease and Alzheimer’s disease by the delay of LPS toxic induced Aβ interactions that involve various proteins such as albumin (Aβ selfassociation) with reduced toxic effects of LPS to astrocyte-neuron crosstalk in the brain.