Oxidative stress versus antioxidant defenses in patients with acute myocardial infarction.

Acute myocardial infarction (AMI) is a highly dynamic event, which is associated with increasing production of reactive oxygen species (ROS). The imbalance between ROS production and antioxidant defenses leads to the condition known as oxidative stress. The most widely recognized effect of increasing oxidative stress is the oxidation and damage of macromolecules, membranes, proteins, and DNA.

Ectonucleotidase and acetylcholinesterase activities in synaptosomes from the cerebral cortex of streptozotocin-induced diabetic rats and treated with resveratrol.

The aim of the present study was to investigate the effects of resveratrol (RV), an important neuroprotective compound on NTPDase, 5'-nucleotidase and acetylcholinesterase (AChE) activities in cerebral cortex synaptosomes of streptozotocin (STZ)-induced diabetic rats. The animals were divided into six groups (n=8): control/saline; control/RV 10mg/kg; control/RV 20mg/kg; diabetic/saline; diabetic/RV 10mg/kg; diabetic/RV 20mg/kg. After 30 days of treatment with resveratrol the animals were sacrificed and the cerebral cortex was removed for synaptosomes preparation and enzymatic assays.

Effect of high glucose levels in human platelet NTPDase and 5'-nucleotidase activities.

Objectives: The objective of this work was to evaluate the effect of different glucose levels on the ATP, ADP and AMP hydrolysis in the platelets of diabetic, hypertensive and diabetic/hypertensive participants.

Methods: The activities of the enzymes NTPDase (ATP and ADP hydrolysis) and 5'-nucleotidase (AMP hydrolysis), and CD39 expression were analyzed in human blood platelets of diabetic (DM-2), hypertensive (HT) and diabetic/hypertensive (DM-2/HT) patients. To evaluate the interference of glucose and fructose in NTPDase and 5'-nucleotidase activities, experiments were performed with glucose, fructose and mannitol concentrations ranging from 5 to 30 mM in platelet-rich plasma (PRP).

Oxidative stress and erythrocyte acetylcholinesterase (AChE) in hypertensive and ischemic patients of both acute and chronic stages.

Ischemic stroke is a leading cause of mortality and disability particularly in the elderly. Hypertension is the most important risk factor in strokes, representing roughly 70% of all cases. Oxidative stress is believed to be one of the mechanisms taking part in neuronal damage in stroke.