RESUMEN
This study investigated the antitumoral, anti-inflammatory and oxidative effects of polysaccharides from tucum (Bactris setosa, TUC) using the Ehrlich carcinoma as a tumor model. Additionally, the glycogen content, cytochrome P levels, and gluconeogenesis from lactate were assessed in the liver of healthy animals. Tumor-bearing female mice were orally treated with 50 and 100 mg.kg-1 of TUC or vehicle, once a day, or with 1.5 mg.kg-1 methotrexate via i.p., every 3 days, along 21 days. Both doses of TUC reduced the tumor weight and volume. In the tumor tissue, it decreased GSH and IL-1ß levels, and increased LPO, NAG, NO and TNF-α levels. The tumor histology showed necrosis and leukocytes infiltration. The metabolic effects of TUC were investigated by measurement of total cytochrome P (CYP) and glycogen in tumor-bearing mice, and by ex vivo liver perfusion on non-bearing tumor male mice, using lactate as gluconeogenic precursor. Metabolically, the hepatic glucose and pyruvate productions, oxygen uptake, and the total CYP concentration were not modified by TUC. Thus, tucum-do-cerrado polysaccharides have antitumor effects through the modulation of oxidative stress and inflammation, without impairing glucose production from lactate in the liver, the main organ responsible for the metabolism of organic and xenobiotic compounds.