Avaliação dos efeitos in vivo e in vitro de ácidos graxos poli-insaturados ômega-3 sobre os efeitos do quimioterápico, ciclofosfamida

Abstract

This study investigated the effects of the long-term dietary fish oil supplementation or the acute administration of the omega-3 fatty acid docosahexaenoic acid (DHA) in the mouse hemorrhagic cystitis (HC) induced by the anti-cancer drug cyclophosphamide (CYP). HC was induced in mice by a single CYP injection (300 mg/kg i.p.). Animals received four different diets containing 10% and 20% of corn or fish oil, during 21 days. Separated groups received DHA by i.p. (1 μmol/kg) or i.t. (10 μg/site) routes, 1 h or 15 min before CYP. The behavioral tests (spontaneous nociception and mechanical allodynia) were carried out from 1 h to 6 h following CYP injection. Bladder inflammatory changes, blood cell counts, and serum cytokines were evaluated after euthanasia (at 6 h). Immunohistochemistry analysis was performed for assessing spinal astrocyte and microglia activation, or GPR40/FFAR1 expression. In vitro studies were conducted to determine the potential effects of DHA on CYP-induced cytotoxicity in human breast cancer cells. Either fish oil supplementation or DHA treatment (i.p. and i.t.) markedly prevented visceral pain, without affecting CYP-evoked bladder inflammatory changes. Moreover, systemic DHA significantly prevented the neutrophilia/lymphopenia caused by CYP, with a partial effect on serum IL-6 levels. DHA also modulated the spinal astrocyte activation and the GPR40/FFAR1 expression. Finally, the pre-incubation of DHA increased the anti-tumor effects of CYP in human breast cancer cells. The supplementation with omega-3 fatty acids-enriched fish oil or parenteral DHA might be interesting nutritional approaches for cancer patients under chemotherapy schemes with CYP