Spices and herbs often contain active phenolic substances endowed with potent antioxidative properties. We had previously shown that curcumin, the yellow pigment in curry, strongly induced HO-1 expression and activity in rat astrocytes. In the CNS, HO-1 has been reported to operate as a fundamental defensive mechanism for neurons exposed to an oxidant challenge. Treatment of astrocytes with curcumin upregulated expression of HO-1 protein at both cytoplasmic and nuclear levels, as shown by immunofluorescence analysis under laser-scanning confocal microscopy. A significant expression of quinone reductase and glutathione S-transferase, two members of phase II detoxification enzymes, was found in astrocytes exposed to 5-15 μM curcumin. Moreover, the effects of curcumin on HO-1 activity were explored in cultured hippocampal neurons. Elevated expression of HO-1 mRNA and protein were detected after 6 h incubation with 5-25 μM curcumin. Higher concentrations of curcumin (50-100 μM) caused a substantial cytotoxic effect with no change in HO-1 protein expression. Interestingly, pre-incubation (18 h) with curcumin resulted in an enhanced cellular resistance to glucose oxidase-mediated oxidative damage; this cytoprotective effect was considerably attenuated by zinc protoporphyrin IX, an inhibitor of heme oxygenase activity. This study gives additional support to the possible use of curcumin as a dietary preventive agent against oxidative stress-related diseases.
|Titolo:||Curcumin Activates Defensive Genes and Protects Neurons Against Oxidative Stress|
|Settore Scientifico Disciplinare:||Settore M-EDF/02 - Metodi e Didattiche delle Attivita' Sportive|
|Data di pubblicazione:||apr-2006|
|Digital Object Identifier (DOI):||10.1089/ars.2006.8.395|
|Appare nelle tipologie:||01 - Articolo su periodico|