Influence of diet manipulation on RBC membrane. Part I: variations of lipid constituents

Functional membranes are 2-dimentional oriented viscous solutions of globular integral proteins dispersed in a fluid phospholipid matrix. Membranes act as a barrier, with selective permeabilities to material and information, thereby maintaining the difference between inside and outside of cells and/or intercellular compartments. The phase changes and thus the fluidity of membranes are highly dependent upon the lipid composition which include the content of phospho- and glycolipids, the ratio between the different molecular species of these compounds and their fatty acids distribution and finally the amount of cholesterol. The lipid composition of membranes may be changed by different factors including temperature, cell development, aging and diet. In order to further substantiate the influence of this last parameter two groups of cows were fed with a normal diet (control) and with a fat supplemented diet containing an increasing high proportion of C16:0, C18:0 and mainly of C18:1 n-9 and a low proportion of C18:2 n-6 and C18:3 n-3 fatty acids: after 63 days the two groups returned to the same diet.