Efecto de los PUFAs dietarios sobre la actividad de enzimas oxidativas en c¨¦lulas tumorales y espl¨¦nicas de un adenocarcinoma de mama

VARA MESSLER M; COMBA A; SORIA EA; QUIROGA PL; SILVA R; PASQUALINI ME; VALENTICH MA

Cordoba

Jornada; XIII Jornada de Investigacion Cientifica de la Facultad de Ciencias Medicas; 2012

FCM-UNC

Effect of dietary PUFAs on oxidative enzymes activity in tumor and spleen cells of a breast adenocarcinoma Vara Messler M, Comba A, Elio Andres S, Quiroga P, Silva R, Pasqualini M, Valentich M. Instituto de Biologia Celular UNC, Hospital Nacional de Clinicas UNC, Doctorado en Ciencias Biom¨¦dicas UNR., C¨¢tedra de Histologia, Embriolog¨ªa y Biologia Molecular UNC, CONICET   Background: Cancer is a multicausal disease. It has shown that a third of cancers are related to food. The consumption of diets enriched with polyunsaturated fatty acids (PUFAs) produce changes in lipid composition of cell membrane fluidity and changes altering the kinetic parameters of enzymes that modify the activity of cyclooxygenases (COXs), lipoxygenases (LOXs) and other enzymes as Gamma-glutamyltranspeptidase (GGTP), peroxidases and nitric oxide synthase (NOS). The incorporation into the membranes of dietary PUFAs-substrates of these enzymes-, and the generation of lipid derivatives, would play an important role in the modulation of carcinogenesis. The aim of this study was to determine the effect of dietary PUFAs on the activity of oxidative enzymes in tumor and spleen cells from mice with mammary tumors. Methods: We isolated tumor and spleen cells of BALB / C and underwent to different diets: 1) experimental diet enriched with Chia oil source of omega-3 and 2) control diet with corn oil, a source of omega-6. The fatty acid profile was analyzed by GC. LOXs and COXs activity was evaluated through eicosanoid generation by HPLC and activity of enzymes GGTP, peroxidases and NOS production of ROS was assesed by spectrophotometry. Results: Mice fed chia diet had a higher percentage of omega-3 in cell membranes compares to those fed with corn diet. Chia treatment resulted in a significant GGTP activity compared with the values for corn (p ¡Ü 0.05). This decrease was associated with increased activity of NOS, and peroxidases. The activity of the enzyme 15-LOX-2, generating 15-HETE (antitumorigenic) was higher in spleen cells from mice treated with chia diet. In contrast, tumor cells from the group chia, generate lower pro-inflammatory eicosanoids (13-HODE, 15-HETE and 5-HETE) than in the control diet (p ¡Ü 0.05). These parameters were correlated with lower weight and tumor volume in the same guests. Conclusion: The omega-3 incorporation to cell membranes modifies the activity of enzymes that produce ROS and eicosanoids, known mediators of the carcinogenic process that may increase the antitumor immune response. Key words: dietary fatty acids, cancer, immunomodulation