Resumen de Alterations in the extracellular catabolism of nucleotides and platelet aggregation induced by high-fat diet in rats: effects of ?-tocopherol
Jessié M. Gutierres, Fabiano B. Carvalho, Maria Rosa Chitolina Schetinger, Marília V. Rodrigues, Juliano M. Vieira, Paula Maldonado, Maria do Carmo S. Araújo, Roberta Schmatz, Naiara Stefanello, Jeandre A. S. Jaques, Marcio Machado Costa, Vera Maria Morsch, Cinthia M. Mazzanti, Victor Pimentel, Sonia Terezinha dos Anjos Lopes, Roselia M. Spanevello
The aim of this study was to assess whether ?-tocopherol administration prevented alterations in the ectonucleotidase activities and platelet aggregation induced by high-fat diet in rats. Thus, we examined four groups of male rats which received standard diet, high-fat diet (HFD), ?-tocopherol (?-Toc), and high-fat diet plus ?-tocopherol. HFD was administered ad libitum and ?-Toc by gavage using a dose of 50 mg/kg. After 3 months of treatment, animals were submitted to euthanasia, and blood samples were collected for biochemical assays. Results demonstrate that NTPDase, ectonucleotide pyrophosphatase/phosphodiesterase, and 5?-nucleotidase activities were significantly decreased in platelets of HFD group, while that adenosine deaminase (ADA) activity was significantly increased in this group in comparison to the other groups (P < 0.05). When rats that received HFD were treated with ?-Toc, the activities of these enzymes were similar to the control, but ADA activity was significantly increased in relation to the control and ?-Toc group (P < 0.05). HFD group showed an increased in platelet aggregation in comparison to the other groups, and treatment with ?-Toc significantly reduced platelet aggregation in this group. These findings demonstrated that HFD alters platelet aggregation and purinergic signaling in the platelets and that treatment with ?-Toc was capable of modulating the adenine nucleotide hydrolysis in this experimental condition.
