γ-Orizanol protege contra dano oxidativo agudo induzido por cádmio em testículos de camundongos

Abstract

Cadmium is a non-essential heavy metal that is present at low levels mainly in food and water and also in cigar smoke. Acute cadmium exposure cause severe testicular damage in mice, which involves oxidative stress. The present study evaluated the testicular oxidative damage caused by acute cadmium exposure and verified the protective role of γ-oryzanol (ORY). Mice received a single dose of 2.5 mg/kg of CdCl 2 administrated via intraperitoneal, and then treated with ORY (50 mM in canola oil, 5 mL/kg) administrated via oral. Testes were removed after 24 hours and tested for lipid peroxidation (TBARS), protein carbonylation, DNA breakage, ascorbic acid, cadmium and non-proteic thiols contents, and for the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST) and δ-aminolevulic acid dehydratase (δ-ALA-D). Cadmium treated group presented an accumulation of this metal in testicular tissue, as well as an increase in lipid peroxidation, protein carbonylation and DNA fragmentation contents, which confirms the oxidative stress. Furthermore, it was noted a significant inhibition in SOD, GST and δ-ALA-D activities, and also a reduction in ascorbic acid and non-proteic thiols content. Therapy reduced significantly cadmium concentration in testes (around 23%). ORY restored SOD and GST activities as well as TBARS production to the control levels. Furthermore, ORY partially recovered δ-ALA-D activity inhibited by cadmium. This study provides the first evidence on the therapeutic properties of ORY in protecting against cadmium-induced testicular toxicity.