Effects of resveratrol in a dopaminergic cell culture model for excitotoxicity
The stilben resveratrol is a phytoalexin found in red wine grapes and is discussed as an antioxidative and anti-inflammatory neuroprotective compound. Resveratrol interacts with the complex III of the respiratory chain and is therefore not just a radical scavenger, but also a substance suppressing radical formation in the mitochondria. In this study, resveratrol was used to investigate its effects on glutamate damages. Excitotoxicity leads to increased formation of superoxide radicals. Therefore, in mesencephalic cell cultures of mice, we studied the influence of trans-resveratrol on the survival rate of dopaminergic neurons and propidium iodide uptake (uPI) after glutamate exposure. On the 10th DIV, glutamate (0, 0.5, or 5mM) was added to the cultures for 15min, and then the cultures were incubated further (48h) in resveratrol-containing (0, 0.01, 0.1, or 1µM) medium. The number of dopaminergic cells remained unaltered when cultures were exposed to resveratrol alone. The compound did not alter the dopaminergic cell number in cultures that were treated with 0.5mM of glutamate, but after exposure to 5mM of the amino acid, resveratrol nearly doubled the number of surviving dopaminergic neurons. At lower concentrations of resveratrol (0.1µM), the uPI was decreased by 28% (0.5mM glutamate) or by 16% (5mM glutamate), respectively. In this study, partial beneficial action of resveratrol (to a concentration up to 0.1µM) in a mesencephalic culture system after glutamate affection could be shown.