title: Purinergic system ecto-enzymes participate in the thromboregulation of patients with indeterminate form of Chagas disease.
abstract: Chagas disease (CD) is a chronic and endemic illness caused by the parasite Trypanosoma cruzi. Microvascular disturbances play an important role in the progress of the disease. The purinergic signaling system participates in regulatory functions, such as immunomodulation, neuroprotection, and thromboregulation. This study aimed to investigate the activities of purinergic system ecto-enzymes present on the platelet surface and the platelet aggregation profile from patients with indeterminate form of Chagas disease (IFCD). Thirty patients diagnosed with IFCD and 30 healthy subjects were selected. Ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP), ecto-5'-nucleotidase (E-5'-NT) and ecto-adenosine deaminase (E-ADA) activities were measured in platelets isolated from these individuals as well as the platelet aggregation. Results demonstrated an increase of 21 % in the E-NPP activity and 30 % in the E-5'-NT activity in IFCD group (P < 0.05); however, a decrease of 34 % in the E-ADA activity was determined in the same group (P < 0.001). A significant decrease of 12.7 % and 12.8 % in the platelet aggregation of IFCD group in two different concentrations of ADP (5 and 10 μM) was observed, respectively (P < 0.05). Increased E-NPP and E-5-NT activities as well as decreased E-ADA activity in platelets of patients with IFCD contributed to decrease platelet aggregation, suggesting that the purinergic system is involved in the thromboregulation process in these patients, since adenosine (the final product of ATP hydrolysis) has cardioprotective and vasodilator effects that prevent the clinical progress of the disease.
authors: Departamento de Microbiologia e Parasitologia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Santa Maria, RS, 97105-900, Brazil.
authors: Viviane do Carmo Gonçalves
authors: Vdo C
authors: Souza
authors: Karine B
authors: KB
authors: Schlemmer
authors: Cristiano B
authors: CB
authors: Noal
authors: Jeandre A S
authors: JA
authors: Jaques
authors: Margarete D
authors: MD
authors: Bagatini
authors: Victor C
authors: VC
authors: Pimentel
authors: Luiz Felipe D
authors: LF
authors: Carli
authors: Cláudio A M
authors: CA
authors: Leal
authors: Juliana
authors: J
authors: Fleck
authors: Maria B
authors: MB
authors: Moretto
authors: Maria R C
authors: MR
authors: Schetinger
authors: Daniela B R
authors: DB
authors: Leal
mesh_terms: D015720:5'-Nucleotidase / Q000378:metabolism*; D000241:Adenosine / Q000378:metabolism; D000243:Adenosine Deaminase / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D001792:Blood Platelets / Q000201:enzymology / Q000378:metabolism; D014355:Chagas Disease / Q000201:enzymology* / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects; D010976:Platelet Count
chemical_list: D000255:Adenosine Triphosphate; D015720:5'-Nucleotidase; D000243:Adenosine Deaminase; D000241:Adenosine