In vitro anti-atherogenic properties of traditional Greek cheese lipid fractions

Given that platelet activating factor (PAF) is a crucial inflammatory phospholipid mediator that is implicated in the mechanism of atherogenesis, the presence of PAF inhibitors in food reinforces their nutritional value in terms of protection against cardiovascular diseases. The aim of the present study was to evaluate the anti-atherogenic (anti-inflammatory) properties of two different types of Greek cheese: Kefalotyri and Ladotyri. Total lipids (TL) of both types of cheese samples were extracted by the method of Bligh and Dyer and separated into total polar lipids (TPL) and total neutral lipids (TNL) by countercurrent distribution. TPL were further separated by preparative thin-layer chromatography (TLC). TL, TPL, TNL and the obtained polar lipid fractions after TLC separation were tested to determine their biological activity towards atherosclerosis based on the in vitro inhibition of PAF-induced platelet aggregation. Both types of cheese samples exhibited strong biological activity, and their lipids were potent PAF inhibitors. Comparing the two types of cheese samples, Ladotyri cheese polar lipid fractions were found to exhibit stronger inhibitory properties than those of Kefalotyri cheese. The fact that both types of cheese were found to contain PAF inhibitors highlights their nutritional value in terms of cardio-protection.