RESUMO
Pancreatic ß-cell death or dysfunction mediated by oxidative stress underlies the development and progression of diabetes mellitus. In the present study, we tested extracts from the edible mushroom Lactarius deterrimus and the chestnut Castanea sativa, as well as their mixture (MIX Ld/Cs), for potential beneficial effects on streptozotocin (STZ)-induced pancreatic ß-cell death. Analysis of chelating effects, reducing power and radical-scavenging assays revealed strong antioxidant effects of the C. sativa extract and MIX Ld/Cs, while the L. deterrimus extract displayed a weak to moderate effect. The antioxidative effect of the chestnut extract corresponds with the high content of phenolics and flavonoids identified by HPLC analysis. In contrast, the mushroom extract contains relatively small amounts of phenols and flavonoids. However, both extracts, and especially their combination MIX Ld/Cs, increased cell viability after the STZ treatment as a result of a significant reduction of DNA damage and improved redox status. The chestnut extract and MIX Ld/Cs significantly lowered the STZ-induced increases in superoxide dismutase and catalase activities, while the mushroom extract had no impact on the activities of these antioxidant enzymes. However, the L. deterrimus extract exhibited good NO-scavenging activity. Different mechanisms that underlie antioxidant effects of the mushroom and chestnut extracts were discussed. When combined as in the MIX Ld/Cs, the extracts exhibited diverse but synergistic actions that ultimately exerted beneficial and protective effects against STZ-induced pancreatic ß-cell death.
Assuntos
Agaricales/química , Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Fagaceae/química , Células Secretoras de Insulina/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Bósnia e Herzegóvina , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Croácia , Dano ao DNA/efeitos dos fármacos , Flavonoides/análise , Frutas/química , Carpóforos/química , Células Secretoras de Insulina/enzimologia , Células Secretoras de Insulina/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Óxido Nítrico/antagonistas & inibidores , Oxirredutases/antagonistas & inibidores , Oxirredutases/metabolismo , Fenóis/análise , Ratos , Estreptozocina/antagonistas & inibidores , Estreptozocina/toxicidadeRESUMO
The aim of this explorative study was to investigate how effective drying preservation methods are in reducing mycotoxin content in figs. Dried autochthonous varieties of white and dark figs (Petrovaca Bijela and Saraguja, respectively) were analysed for mycotoxins using an LC-MS/MS "dilute and shoot" method capable of determining 295 fungal and bacterial secondary metabolites. Before drying in a cabinet dryer the figs were preserved with 0.5 % citric acid solution or 0.5 % ascorbic acid solution or 0.3 % L-cysteine solution or 0.2 % chestnut extract solution or 0.15 % Echinacea extract solution by immersion. We found nine metabolites: aflatoxin B1 (AFB1), ochratoxin A, ochratoxin alpha, kojic acid, emodin, altenuene, alternariol methyl ether, brevianamide F, and tryptophol. The most efficient preserver was L-cysteine (15 % reduction), while ascorbic acid favoured mycotoxin production (158 % increase). However, all pretreatment solutions reduced AFB1, which is a major fig contaminant.