Absorption of omega-3 fatty acids by biomembrane models studied by differential scanning calorimetry

Omega-3 fatty acids, contained in vegetables and fish, exert several beneficial effects on the human health. The interaction of three omega-3 fatty acids (linolenic acid, docosapentaenoic acid and docosahexaenoic acid) with and their absorption by biomembrane models (represented by dimyristoylphosphatidylcholine multilamellar and unilamellar vesicles) were studied to get possible information on how the absorption process of these compounds by the cell membranes after the intake of omega-3 fatty acids containing food could be. The differential scanning calorimetry technique was employed. The interaction of omega-3 fatty acids/vesicles was detected analysing phospholipid vesicles prepared in the presence of increasing amounts of the fatty acids. The absorption kinetics of omega-3 fatty acids absorption by biomembranes was investigated setting pure phospholipid vesicles in contact with omega-3 fatty acids dissolved in the aqueous medium. Docosapentaenoic acid and docosahexaenoic acid interact with biomembrane models stronger than linolenic acid. In the aqueous medium the absorption of omega-3 fatty acids by unilamellar vesicles was faster than that by multilamellar vesicles. The omega-3 fatty acids are absorbed by the biomembrane models gradually and almost completely. The results suggest that the transfer of omega-3 fatty acids from food to biomembranes could be influenced by the compounds structure and by the medium in which they are dissolved.