Citoproteção do ácido kójico (AK) na morte induzida por LPS em células de Muller de retina de embrião de galinha

Abstract

5-Hydroxy-2-hydroxymethyl-γ-pyrone (AK), a known inhibitor of tyrosinase, an enzyme important for melanin synthesis and therefore used for pigmentation disorders. AK also promotes significant activation of macrophages and promotes cytoplasmic accumulation of reactive oxygen species (ROS), suggesting its role as a potentiator of the immune system and microbicide. There is no work in literature that shows the action of AK in the central nervous system (CNS) as a cellular activator and its possible protective role against infections. To test this hypothesis, it use retinal Muller glia which have similar properties to those of macrophages. Therefore, the present work evaluates the action of AK as a possible protective role in LPS-induced cell death in culture of glial cells from chicken embryos. Cultures enriched with glial cells were treated with AK (10, 25, 50 and 100 μM) and LPS (0.1, 10, 100, and 500 ng / ml) for 24 hours. After treatment, the cells did not show AK-treated cytotoxicity; however, treated with LPS, cell death occurred in a dose-dependent manner. We verified the accumulation of EROs in groups treated with AK (100 μM) and LPS (100 and 500 ng / ml). Cultures co-treated with AK and LPS in the same concentrations there was a reduction of accumulation of EROs. AK was also able to inhibit the activity of antioxidant enzymes, (catalase and Superoxide dismutase) and glutathione levels, while LPS produces an increase in the activity of these antixodants. AK was able to inhibit the antioxidant enzymes and glutathione from the increase induced by LPS. These data show that AK promotes the modulation of oxidative and antioxidative balance as a possible protective mechanism in the cell death produced by LPS in Müller's Glia enriched cells.