Antioxidative capacity in the fat body of Bombyx mori is increased following oral administration of 4-methylumbelliferone

Abstract

Plant sources of umbelliferones have tumor-inhibitory effects at the cellular level. However, their physiological functions in animals are largely unresolved. In this study, we provide evidence to show that 4-methylumbelliferone (4-MU) participates in the regulation of antioxidative capacity in the fat body of Bombyx mori, a tissue similar to mammalian liver in this model invertebrate. Larvae (3rd day of the 5th instar) were orally exposed to 4 mM 4-MU, an umbelliferone, which swiftly induced the generation of a large number of ROS (e.g. H2O2 increased 6 to 8-fold), and 4-MU was detected in the fat body 8 min after administration. In addition, the activities of CAT and GPx were up-regulated 4 to 11-fold and 2 to 16-fold, respectively, and were helpful in defending fat body cells against oxidative injury in combination with NADPH. Furthermore, significant increases in the contents of T-AOC (up to approx. 2-fold), antioxidants of ASAFR (by 2 to 4-fold) and GSH were detected.

Keywords: 4-Methylumbelliferone; 4-methylumbelliferone; 4MU; ASAFR; Anti-oxidant; Bombyx mori; CAT; DEPC; Fat body; Fb; GCL; GPx; GR; GSH; GSSG; NADH oxidase; NOX-1; Oxidative stress response; ROS; Reactive oxygen species; SOD; T-AOC; anti-superoxide anion free radical; catalase; diethyl pyrocarbonate; fat body; glutathione peroxidase; glutathione reductase; oxidized glutathione; reactive oxygen species; reduced glutathione; superoxide dismutase; total antioxidant capacity; γ-glutamate-cysteine ligase.