Correlation of Plasma Neutrophil Elastase Activity and Endogenous Protease Inhibitor Levels with the Severity of Pre-eclampsia.

Abstract

Pre-eclampsia (PE) is a common maternal syndrome characterized by severe systemic inflammatory response including neutrophil activation leading to uncontrolled activity of elastase. The excessive activity of elastase would lead to destroyal of the integrity of endothelial cells and could exacerbate the pathophysiological symptoms in PE. Thus, assessment of NE activity and its control mechanisms would be of relevance in the determination of severity of PE. To correlate the activity of plasma NE and its endogenous inhibitors α1-antitrypsin (α1-AT) and α2-macroglobulin (α2-MG) with severity of PE. A comparative study was conducted between normotensive pregnant (n=50) and pre-eclamptic (n=50) women. Serum C-Reactive Protein (CRP) was estimated by rapid latex slide and uric acid by uricase method. Plasma elastase was estimated using succinyl tri- L-alanyl-p-nitroanilide as substrate. Plasma α1-AT, α2-MG and NE- α1-AT complex were quantified by ELISA. ANOVA and Pearson's correlation tests were used to analyze the data. The results were expressed as mean±SD and p-value <0.001 was considered statistically highly significant. The activity of elastase was increased significantly in severe PE (0.62±0.08) in comparison to normal (0.35±0.10) and mild pre-eclamptic subjects (0.37±0.03). The values of α1-AT were significantly less in mild (83.94±25.08) and severe PE (68.58+26.39) in comparison to normal (110.26±42.39). There was a significant rise in the levels of α2-MG in severe PE. However, the complex estimation did not evince any significant changes. The results of the present study indicate a significantly elevated elastase activity, α2-MG levels and decreased α1-AT in severe PE patients. The correlation analyses of PE severity parameters with NE, α1-AT and α2-MG further support the roles of these molecules in the assessment of severity of PE.