Biochemical characterization of chitotriosidase enzyme: comparison between normal individuals and patients with Gaucher and with Niemann–Pick diseases

Abstract

Objectives: The aim of the present study was to establish the range of chitotriosidase (CT) activity in normal individuals, patients with Gaucher disease (GD) and Niemann–Pick disease (NPD), types A or B. The kinetics of CT in these three groups was also investigated . Design and methods: CT activity, as well as K m, V max, optimum pH, and thermal stability of the enzyme were determined in the plasma of control, GD, and NPD subjects. Results: CT activity in GD and NPD patients was, respectively, around 600-fold and 30-fold greater than in normal individuals. We observed significant differences in optimum pH, V max, and thermal stability between the various groups. K m was different in normal individuals relative to GD and NPD patients. However, there was no significant difference between K m values in patients with GD and with NPD. Conclusions: Based on the differences found in the biochemical parameters studied, our results may be important to help the identification of patients not only with GD but also with NPD.