The Clinical Significance Of Von Willebrand Factor Cleaving Protease (ADAMTS13) And Thrombospondin1 In Acute Ischemic Stroke

Objective Ischemic stroke is an arterial thrombosis disease,with a 75% incidence among acute cerebrovascular diseases.The incidence is increasing with age.The pathogenesis is ischemic necrosis of local brain tissue due to lack of blood supply.The most common cause of ischemic stroke is the formation of atherosclerotic plaque on the blood vessel wall,the fracture of the plaques and secondary thrombosis formation. Von Willebrand factor(vWF) is the main ingredient of the arterial thrombosis,especially microvascular thrombosis.It's been proved that the larger of vWF multimer molecular weight,the stronger of the ability of inducing the platelet gathering to form thrombosis.It is known now that there is a variety of enzymes adjusting the size of vWF multimers in human body.Among the enzymes which could affect the ability of vWF inducing aggregation of the platelet are von Willebrand factor-cleaving protease(vWF-CP)and thrombospondinl (TSP1).VWF-CP is also known as ADAMTS13 which is a metalloprotease that can regulate structure and function of vWF,and its activity is changing in many physiological or pathologic state.TSP1 is a member of the glycoprotein family in extracellular matrix which includes many functional structure domains,and it gradually becomes a research hotspot for its function in the hemostasis and the relationship between thrombotic diseases and TSP1.This study mainly investigates the possible role of vWF,ADAMTS13,TSP1 in the pathogenesis of acute ischemic stroke.Methods 30 hospitalized patients with acute ischemic stroke were randomly selected in neurology department from May 2010 to January 2011.30 healthy controls matched for sex and age with the study population were voluntary blood donors.The expression of plasma vWF and the concentration of TSP1 in patients and controls were measured by enzyme linked immunosorbent assay(ELISA);the activity of ADAMTS13 was measured by residual-collagen binding assay(R-CBA).The results were showed in a way of x±s,the index have been compared with t test,and the correlation was analysed with Pearson correlation analysis.Results (1).The activity of ADAMTS13 was significantly lower in patients with acute ischemic stroke compated to normal controls(p<0.01),the level of vWF and the concentration of TSP1 were significantly higher in patients with acute ischemic stroke compated with normal controls(P<0.01).(2).Negative correlation was observed betwee the activity of ADAMTS13 and the concentration of TSP1 in patients with acute ischemic stroken(r=-0.61, P<0.05).Conclusion (1).There may exist a relationship between the decreased activity of plasma AD AMTS13 and the arterial thrombosis of ischemic stroke, and the increased level of vWF and TSP1 may be related with the formation of arterial thrombosis in acute ischemic stroken.(2).The negative correlation between ADAMTS13 and TSP1 in patients with acute ischemic stroke suggests there may be a competitive mechanism between TSP1 and ADAMTS13 in the degradation of vWF.