Antioxidant and pro-oxidant properties of boldine on hippocampal slices exposed to oxygen-glucose deprivation in vitro.
ABSTRACT Boldine is one of the most potent natural antioxidants and displays some important pharmacological activities, such as cytoprotective and anti-inflammatory activities, which may arise from its free radical scavenging properties. Given that the pathogenesis of brain ischemia/reperfusion has been associated with an excessive generation of oxygen free radicals, the aim of this study was to evaluate the neuroproperties of boldine using hippocampal slices from Wistar rats exposed to oxygen and glucose deprivation (OGD), followed by reoxygenation, to mimic an ischemic condition. The OGD ischemic condition significantly impaired cellular viability, increased lactate dehydrogenase (LDH) leakage and increased free radical generation. In non-OGD slices, incubation with 100microM boldine significantly increased LDH released into incubation media and decreased mitochondrial activity, suggesting an increase of tissue damage caused by boldine. However, slices incubated with 10microM boldine during and after OGD exposure had significantly increased cellular viability with no effect on cell damage. Total reactive antioxidant potential (TRAP) levels measured for this alkaloid showed an antioxidant potential three times higher than Trolox, which acts as a peroxyl radical scavenger. Moreover, boldine prevented the increase in lipoperoxidation levels induced by ischemia, but higher concentrations potentiated this parameter. These results confirm the potent antioxidant properties of this alkaloid, and add evidence to support the need for further investigations in order to confirm the potential pro-oxidant effects of boldine at higher doses.
Article: Catuaba (Trichilia catigua) Prevents Against Oxidative Damage Induced by In Vitro Ischemia–Reperfusion in Rat Hippocampal Slices[show abstract] [hide abstract]
ABSTRACT: Oxidative stress is implicated in brain damage associated with ischemia–reperfusion. Natural antioxidants found in some plants used in folk medicine have been indi-cated as potential neuroprotective agents. Here we investi-gated whether Trichilia catigua, a traditional Brazilian herbal medicine alleged to exhibit a variety of neurophar-macological properties (antidepressant, anti-neurasthenic, anti-inflammatory etc.), could have neuroprotective prop-erties in rat hippocampal slices subjected to 2 h oxygen and glucose deprivation (OGD) followed by 1 h reper-fusion. Ischemia–reperfusion (I/R) significantly decreased mitochondrial viability, increased dichlorofluorescein oxi-dation above control both in the incubation medium and slices homogenates, increased lactate dehydrogenase into the incubation medium and decreased non-protein thiols. T. catigua (40–100 lg/mL) protected slices from the dele-terious effects of OGD when present before OGD and during the reperfusion periods. Oxidative stress in the medium was also determined under different conditions and the results demonstrated that T. catigua could not protect slices from I/R when it was added to the medium after ischemic insult. Although the translation to a real in vivo situation of I/R is difficult to be done, the results indicated that T. catigua should be used as preventive and not as a curative agent against brain damage.Neurochemical Research 09/2012; 2.4. · 2.24 Impact Factor