In vitro and in vivo influence of plant preparations on dipeptidyl peptidase IV and adenosine deaminase activities

Abstract

Dipeptidyl peptidase IV (DPPIV) and adenosine deaminase (ADA) are multifunctional enzymes, involved in different physiological processes. Often a problem of their regulation appears. Particularly, the inhibition of both enzymes considered beneficial at type 2 diabetes. This work describes the influence of ethanol extracts and constituents from several plants on DPPIV and ADA activities. The IC50 values of extracts from pellicles of walnut kernel, rose petals, melilot, leaves of pistacia, grape, sorrel and blackberry in the in vitro inhibition of ADA from bovine lung were in the range of 0.23-1.25 mg/ml. In inhibition of DPPIV from bovine kidney, the IC50 values of the extracts from blackberry leaves, pellicles of walnut kernel and rose petals were between 0.13 and 0.63 mg/ml. The IC50 values of phenol glycoside fractions from rose petals and grape leaves in DPPIV inhibition (0.029 mg/ml) were by one order smaller than for ADA (0.34 mg/ml). In the in vivo experiments, the increasing of ADA and DPPIV activities in the blood plasma of the streptozotocin injected rats (40 mg/kg of body weight) was proved. In these animals the extract from walnut kernel pellicles effectively inhibited the activities of both enzymes.Dipeptidyl peptidase IV (DPPIV) and adenosine deaminase (ADA) are multifunctional enzymes, involved in different physiological processes. Often a problem of their regulation appears. Particularly, the inhibition of both enzymes considered beneficial at type 2 diabetes. This work describes the influence of ethanol extracts and constituents from several plants on DPPIV and ADA activities. The IC50 values of extracts from pellicles of walnut kernel, rose petals, melilot, leaves of pistacia, grape, sorrel and blackberry in the in vitro inhibition of ADA from bovine lung were in the range of 0.23-1.25 mg/ml. In inhibition of DPPIV from bovine kidney, the IC50 values of the extracts from blackberry leaves, pellicles of walnut kernel and rose petals were between 0.13 and 0.63 mg/ml. The IC50 values of phenol glycoside fractions from rose petals and grape leaves in DPPIV inhibition (0.029 mg/ml) were by one order smaller than for ADA (0.34 mg/ml). In the in vivo experiments, the increasing of ADA and DPPIV activities in the blood plasma of the streptozotocin injected rats (40 mg/kg of body weight) was proved. In these animals the extract from walnut kernel pellicles effectively inhibited the activities of both enzymes.