title: Altered E-NTPDase/E-ADA activities and CD39 expression in platelets of sickle cell anemia patients.
abstract: Sickle cell anemia (SCA) is a hemoglobinopathy characterized by hemolysis and vaso-occlusions caused by rigidly distorted red blood cells. Sickle cell crisis is associated with extracellular release of nucleotides and platelets, which are critical mediators of hemostasis participating actively in purinergic thromboregulatory enzymes system.This study aimed to investigate the activities of purinergic system ecto-enzymes present on the platelet surface as well as CD39 and CD73 expressions on platelets of SCA treated patients. Fifteen SCA treated patients and 30 health subjects (control group) were selected. Ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-5'-nucleotidase (E-5'-NT) and ecto-adenosine deaminase (E-ADA) activities were measured in platelets isolated from these individuals. Results demonstrated an increase of 41 % in the E-NTPDase for ATP hydrolysis, 52% for ADP hydrolysis and 60 % in the E-ADA activity in SCA patients (P<0.05); however, a two folds decrease in the CD39 expression in platelets was observed in the same group (P<0.01). The increased E-NTPDase activity could be a compensatory mechanism associated with the low expression of CD39 in platelets. Besides, alteration of these enzymes activities suggests that the purinergic system could be involved in the thromboregulatory process in SCA patients.
authors.affiliation: Departamento de Microbiologia e Parasitologia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil; Programa de Pós-Graduação em Ciências Farmacêuticas, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil. Electronic address: liviagelain@gmail.com.
authors.forename: Lívia G
authors.initials: LG
authors.lastname: Castilhos
authors.affiliation: ​Programa de Pós-Graduação em Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil.
authors.forename: Pedro H
authors.initials: PH
authors.lastname: Doleski
authors.affiliation: ​Programa de Pós-Graduação em Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil; Department of Biochemistry, Federal University of Technology, P. M. B. 704, Akure, Nigeria.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Adefegha
authors.affiliation: ​Programa de Pós-Graduação em Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil.
authors.forename: Lara V
authors.initials: LV
authors.lastname: Becker
authors.affiliation: ​Programa de Pós-Graduação em Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil.
authors.forename: Jader B
authors.initials: JB
authors.lastname: Ruchel
authors.affiliation: Departamento de Microbiologia e Parasitologia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil; Programa de Pós-Graduação em Ciências Farmacêuticas, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil; ​Programa de Pós-Graduação em Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Av. Roraima, 97105-900, Santa Maria-RS, Brazil. Electronic address: daniela.leal@ufsm.br.
authors.forename: Daniela B R
authors.initials: DB
authors.lastname: Leal
mesh_terms: D015720:5'-Nucleotidase / Q000378:metabolism*; D000243:Adenosine Deaminase / Q000378:metabolism*; D000244:Adenosine Diphosphate / Q000378:metabolism; D000249:Adenosine Monophosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000755:Anemia, Sickle Cell / Q000201:enzymology*; D015703:Antigens, CD / Q000378:metabolism*; D001081:Apyrase / Q000378:metabolism*; D001792:Blood Platelets / Q000201:enzymology* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D005434:Flow Cytometry; D058851:GPI-Linked Proteins / Q000378:metabolism; D006801:Humans; D008297:Male; D055815:Young Adult
chemical_list: D015703:Antigens, CD; D058851:GPI-Linked Proteins; D000249:Adenosine Monophosphate; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D015720:5'-Nucleotidase; C548241:NT5E protein, human; D000243:Adenosine Deaminase; D001081:Apyrase; C067869:CD39 antigen
keywords: Adenosine deaminase; CD39; CD73; Platelet; Sickle cell anemia