EVALUATION OF HOMOCYSTEINE BINDING WITH A FRACTION OF PLASMA PROTEINS ASSOCIATED WITH VASCULAR REMODELING

Abstract

Elevated levels of homocysteine (Hcy) in tissues cause cytotoxic effects. Increase in the overall conсentration of the various Hcy chemical forms above 12 μM is called hyperhomocysteinemia. The term «total homocysteine» of plasma (tHcy) is the sum of concentrations of aminothiol in reduced (-SH) and oxidized (-SS-) forms. It was suggested that the S- and, partially, N-homocysteinylation of proteins plays a major role in the toxic effects of Hcy. The rate of tHcy in plasma is not closely related to pathological process with remodeling of the vascular wall and not entirely suitable for prospective evaluation of the pathologic process. The paper presents the method of evaluation of the tHcy and its fraction after ultrafiltration, allowing cut off proteins with mass above 300 kDa. Proteins in this fraction which can form a mixing disulfides of Hcy include apoB protein and activated alpha-2-macroglobulin. The proposed Hcy estimation in plasma preparations prior and after ultrafiltration may be performed in any laboratory with kits for tHcy evaluation in plasma. Evaluation of Hcy fraction associated with > 300 kDa plasma proteins by means of centrifugal device Vivaspin 300 000 MWCO PES «Sartorius» provides information about Hcy transport by an additional way in macrophages, endothelial cells, smooth muscle cells and others in vascular wall by receptorial endocytosis.