Nucleoside triphosphate diphosphohydrolases (NTPDase) inhibitory activity of some medicinal plants

Nucleoside triphosphate diphosphohydrolasess (NTPDases, EC 3.6.1.5) are well characterized ectoenzymes which are involved in the hydrolysis of ATP and ADP resulting in the formation of nucleoside monophosphates and orthophosphate. By hydrolyzing circulating ATP to ADP to AMP, NTPDases play a crucial role in preventing the activation of platelets and their aggregation. NTPDase inhibitors therefore are currently target for various cardiovascular diseases and some types of cancer. In search for new enzyme inhibitors of therapeutic importance, the present study was conducted to find out the inhibitors of NTPDase from methanolic extracts of 50 medicinal plants used in folk medicine. Data shows that only 6 plants exhibited anti-NTPDase activity above 50% with crude enzyme preparation of chicken liver at 125 μg plant extract. These plants included, Cymbopogan jawarancusa, (51.16±4.81%), Asparagus officinalis (58.24±0.93%), Tribulus terrestris (50.84±6.19%), Rubia cordizolla (53.11±3.49%), Echimops echimatus (51.48±6.29%) Portulaca oleracea (52.79±0.10%). These studies are priliminary findings and further work is required to explore these plants using purified enzyme preparations.