title: Effect of high glucose levels in human platelet NTPDase and 5'-nucleotidase activities.
abstract: OBJECTIVE
  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). Pre-incubation times of 10, 120 min and 24h were used.
  
  
  RESULTS
  NTPDase and 5'-nucleotidase activities increased with increasing glucose and fructose concentrations (P<0.001) and the different times of pre-incubation did not interfere in ectonucleotidases activities (P>0.5). NTPDase and 5'-nucleotidase activities demonstrated a positive correlation between serum glucose levels and ATP and ADP hydrolysis in DM-2 and DM-2/HT patients. CD39 expression demonstrated that DM-2, HT and DM-2/HT groups presented a significant increase when compared to the control group (P<0.004).
  
  
  CONCLUSIONS
  The hydrolysis of adenine nucleotides is enhanced in platelets of patients with diabetes and hypertension. We observed that an increasing glucose concentration had a direct effect on ATP, ADP and AMP hydrolysis. Furthermore, CD39 expression was enhanced in all patients groups, indicating that these enzyme activities are related with diabetes and hypertension.
authors.affiliation: Departamento de Química, Centro de Ciências Naturais e Exatas, Programa de Pós-Graduação em Bioquímica Toxicológica, Universidade Federal de Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Gilberto Inácio
authors.initials: GI
authors.lastname: Lunkes
authors.forename: Daniéle Sausen
authors.initials: DS
authors.lastname: Lunkes
authors.forename: Daniela
authors.initials: D
authors.lastname: Leal
authors.forename: Maria do Carmo
authors.initials: Mdo C
authors.lastname: Araújo
authors.forename: Maísa
authors.initials: M
authors.lastname: Corrêa
authors.forename: Lara
authors.initials: L
authors.lastname: Becker
authors.forename: Cintia Saydelles da
authors.initials: CS
authors.lastname: Rosa
authors.forename: Vera Maria
authors.initials: VM
authors.lastname: Morsch
authors.forename: Maria Rosa Chitolina
authors.initials: MR
authors.lastname: Schetinger
mesh_terms: D015720:5'-Nucleotidase / Q000097:blood*; D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000378:metabolism; D015703:Antigens, CD / Q000097:blood; D001081:Apyrase / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D001792:Blood Platelets / Q000187:drug effects / Q000201:enzymology*; D002097:C-Reactive Protein / Q000378:metabolism*; D002784:Cholesterol / Q000097:blood; D048909:Diabetes Complications / Q000097:blood / Q000201:enzymology; D003920:Diabetes Mellitus / Q000097:blood* / Q000201:enzymology; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000201:enzymology; D008875:Middle Aged; D043583:Nucleoside-Triphosphatase / Q000097:blood*
chemical_list: D015703:Antigens, CD; D001786:Blood Glucose; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D002097:C-Reactive Protein; D002784:Cholesterol; D015720:5'-Nucleotidase; D043583:Nucleoside-Triphosphatase; D001081:Apyrase; C067869:CD39 antigen; D005947:Glucose