[Oxidative modification of lipoprotein (a): physical chemical aspects and biologic implications]

Lipoprotein(a) [Lp(a)] is an atherogenic lipoprotein with unknown functions, consisting of a low-density lipoprotein (LDL) core and the apo(a) glycoprotein. Apo(a) shares an homology with the fibrinolytic proenzyme plasminogen; the characteristic feature of apo(a) is the presence of multiple so called "kringles" repeats which are in part identical and in part exhibit slight sequence differences with regard to plasminogen. The atherothrombogenic properties of Lp(a) appear to be related either to its similarity to LDL (i.e., a proatherogenic effect) or to the apo(a) similarity to plasminogen (i.e., a prothrombotic/antifibrinolytic effect). Oxidative modification also could explain, at least partly, the participation of Lp(a) in the development of atheromatous lesions. In this review, we expose the main characteristics of in vitro oxidation of Lp(a), and the possible consequences on Lp(a) pathogenicity.