Avaliação Da Atividade De Nucleotidases E Parâmetros De Estresse Oxidativo Em Pacientes Com Esclerose Múltipla E Em Modelo Experimental De Desmielinização Em Ratos

Content Provider	Semantic Scholar
Author	Spanevello, Roselia M.
Copyright Year	2009
Abstract	Multiple sclerosis (MS) is the main demyelinating disease of the central nervous system (CNS). It is the most common cause of neurological disability among young adults. Immune, neurological and vascular alterations are found in MS and it has been postulated that oxidative stress may be involved in the pathogenesis of this disease. The nucleotides ATP, ADP and nucleoside adenosine are important molecules that modulate several biological processes including thromboregulation, inflammation and neurotransmission. The control of extracellular levels of these molecules and consequent purinergic signaling induced by them is controlled by a variety of enzymes such as NTPDases (Nucleotide Triphosphates Diphosphohydrolase), E-NPPs (Ecto-Nucleotide Pyrophosphatase Phosphodiesterases), 5'-nucleotidase and adenosine deaminase (ADA). Therefore, the objective of this study was to evaluate the activity of these ectoenzymes in lymphocytes and platelets of patients with the relapsing remitting form of MS (RRMS) as well as the role of NTPDase and 5'nucleotidase in synaptosomes and platelets and oxidative stress parameters in rats subjected to experimental demyelination with ethidium bromide (EB) and treated with vitamin E. The results showed changes in ectoenzyme activities in lymphocytes and platelets of RRMS patients. In lymphocytes, an increase in NTPDase activity and expression along with a decrease in ADA activity was observed in patients with RRMS when compared with the control group. A decrease in NTPDase activity and expression and a decrease in E-NPP, 5'nucleotidase and ADA activities was observed in platelets of RRMS patients when compared with healthy subjects. As for the experimental model, the results showed that rats subjected to demyelination by EB demonstrated increased NTPDase and 5'-nucleotidase activities in both synaptosomes and platelets. When demyelinated rats were treated with vitamin E this increase in NTPDase was reversed, however 5'-nucleotidase activity remained increased in synaptosomes and platelets when compared with the control group. Furthermore, we observed that oxidative stress parameters such as TBARS content and non-protein thiols were increased and catalase activity was decreased in demyelinated rats and that treatment with vitamin E reversed these changes in the control group. The results reported here suggest that ectoenzymes are involved in the modulation of immune, vascular and neurological responses, thus having an important role both in MS and in experimental models of demyelination. Moreover, vitamin E may interfere with the hydrolysis of adenine nucleotides and oxidative stress during a demyelinating event which suggests that this compound could be important in the treatment of demyelinating diseases such as MS.
File Format	PDF HTM / HTML
Alternate Webpage(s)	https://lume.ufrgs.br/bitstream/handle/10183/17418/000716951.pdf;jsessionid=B41532B79D2A3220968606FB8C3B5074?sequence=1
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article