Collectins, C3 complement protein, annexin V and C-reactive protein in acute ischemic stroke: interrelation and implication to upregulated apoptosis and inflammation

Abstract

Upregulated inflammatory response and apoptosis, both triggered by ischemia, are the most destructive pathologic processes developed after acute ischemic stroke (IS) at both central and peripheral levels. Identification of molecular mediators of these processes and understanding of their pathomechanisms will support the development of therapies, which can significantly improve outcomes of IS-affected subjects.Mannan-binding lectin (MBL), ficolin L (FL), ficolin H (FH) and C3 complement proteins participate in apoptotic cells recognition and clearance through various mechanisms. In the present study we performed comparative determination of the blood levels of MBL, FL and FH, and hemolytic activity of C3 protein (C3H50) as well as apoptosis marker protein, circulating annexin V (cANXV), and inflammatory marker C-reactive protein (CRP) in 99 patients with acute IS on the first day of stroke onset and 110 healthy subjects. Potential correlation between all measured parameters was analyzed. Methods included enzyme-linked immunosorbent, hemolytic, and immunonephelometric assays; statistics were performed by Student's t-test and Pearson's correlation analysis. The obtained data demonstrated significantly increased and correlated with each other blood levels of MBL and C3H50, cANXV and CRP in patients compared to controls. Slight, while significant, changes in the blood levels of FL and FH were also observed. We concluded that post-ischemic response at the first day of IS onset is characterized by sufficiently elevated and positively correlated with each other blood levels of MBL, C3H50, cANXV and CRP as well as by slightly increased blood levels of FH and FL. The obtained results suggest that MBL and C3 protein are implicated in upregulated inflammatory response and apoptosis developed after IS onset at a peripheral level, and that these pathological processes are interrelated and interdependent.