Testing of plant extracts for neuroprotective effects in hippocampal slice cultures

Activity: Talks and presentationsTalks and presentations in private or public companies

Description

*J. ZIMMER1, J. NORABERG1, K. B. CHRISTENSEN2, K. GREVSEN3, J. SINDBERG1;
1Neurobiol. Res., Univ. Southern Denmark, DK-5000 Odense C, Denmark; 2Chem. Engineering, Biotech. and Envrn. Technol., Univ. Southern Denmark, Odense C, Denmark; 3Dept. of Horticulture,Aarhus Univ., Aarhus, Denmark
Abstract: Plants are a major source of known and potentially new health promoting, neuroprotectivecompounds. Plant compounds with such properties are therefore attractive as natural components or supplements in functional food and as leads for novel drugs in treatment or prevention of neurodegene-rative disorders.
Taking advantage of a sensitive, hippocampal slice culture-based model for glutamate receptor mediated, ischemia-induced neurodegene-ration, we started to screen extracts of selected plant species for neuroprotec-tive (or neurotoxic) effects, measured against a standardized excitotoxic NMDA lesion. Hippocampal slice cultures derived from 8 day old rat pups (Sprague Dawley strain) were grown for 2-3 weeks before exposed for 24 hrs to 10 μM of the glutamate receptor agonist NMDA, known to induce 50% CA1 pyramidal cell death, with and without addition of plant extracts. Induced neuronal cell death was quantified by recording cellular uptake of the fluorescent dye propidium iodide before and after exposure. Plant extracts examined with positive effect so far include the medicinal plant Rhodiola rosea (golden root), the herb Salvia officinalis (sage) and the vegetable Brassica oleracea var. italic (broccoli). Crude methanolic extracts of these plants displayed a significant and dose-dependent protection of hippocampal CA1 pyramidal cells against NMDA excitotoxicity. Neuroprotection by golden root was observed for concentrations ranging from 50-500 μg/ml with maximal reduction in cell death to 47% of lesion-only cultures. Broccoli extracts at 50-100 μg/ml conc. provided a maximal reduction of 37%, while sage extracts in 100-250 μg/ml conc. reduced cell death to 32%. Ongoing experiments, using standards of major metabolites present in the extracts as well as bioassay-guided chromatographic fractionations, aim to identify the bioactive compounds in these extracts. Investigations of mechanisms of action will include test for anti-inflammatory effects, effects on glutamate transporters and selected gene expression analyses by real time PCR of microdissected samples of the CA1 pyramidal cell layer.
We conclude that screening for neuroprotective effects of crude plants extracts in a brain slice culture model of cerebral ischemia is feasible for first level selection of plants species and extracts, in this case golden root, sage and broccoli

Period13. Nov 201017. Nov 2010
Event titleNanosymposium at 40th Annual Meeting of the Society for Neuroscience
Event typeConference
LocationSan Diego, United States