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Unformatted text preview: ORIGINAL PAPER An involvement of BDNF and PI3-K/Akt in the anti-apoptotic effect of memantine on staurosporine-evoked cell death in primary cortical neurons D. Jantas Æ M. Szymanska Æ B. Budziszewska Æ W. Lason Published online: 12 June 2009 Ó Springer Science+Business Media, LLC 2009 Abstract Memantine, a clinically used NMDA receptor antagonist possesses neuroprotective properties, but the exact mechanisms of its beneficial action on neuronal survival are poorly recognized. In the present study, some intracellular mechanisms of memantine effects on stauro- sporine-evoked cell death were investigated in primary cortical neurons. Memantine (0.1–2 l M) suppressed neu- ronal apoptosis evoked by staurosporine in 7 DIV cortical neurons, whereas other antagonists of NMDA receptor, MK-801 (1 l M) and AP-5 (100 l M) were ineffective. The anti-apoptotic effects of memantine were not connected with any changes in cytoplasmic calcium concentration or reactive oxygen species level. The immunoblot analysis showed that the staurosporine induced a decrease in p-Akt protein kinase level and that this effect was reversed by memantine treatment. Moreover, the PI3-K inhibitors, wortmannin and LY 294002 attenuated the anti-apoptotic action of memantine on staurosporine-induced cell dam- age. Furthermore, the ELISA studies showed increased cellular and released BDNF protein level after combined treatment with memantine and staurosporine. There was no effect of memantine on the activation and expression of other protein kinases involved in the mechanism of cellular survival, i.e. ERK1/2, JNK and GSK3- b . The obtained data suggest an NMDAR-independent action of memantine in attenuation of neuronal apoptosis and point to the engagement of BDNF and PI3-K/Akt pathway in these processes. Keywords Neuronal apoptosis Neurotoxicity NMDA receptor antagonist Wortmannin Intracellular calcium level JC-1 Abbreviations Akt Protein kinase Akt, protein kinase B AP-5 2-Amino-5-phosphopentanoic acid BDNF Brain-derived neurotrophic factor CREB cAMP response element-binding protein DIV Day in vitro ERK1/2 Extracellularly regulated protein kinase 1/2 GSK3- b Glycogen synthase kinase 3- b JC-1 5 ,6,6-Tetrachloro-1,1,3,3- tetraethylbenzimidazolcarbocyanine iodide JNK c-Jun NH(2)-terminal kinase LDH Lactate dehydrogenase MAPK Mitogen-activated protein kinase MMP Mitochondrial membrane potential MTT 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide NMDA N-Methyl- D-aspartic acid PI3-K Phosphatidylinositol-3 kinase St Staurosporine Introduction Memantine (3,5-dimethyl-1-adamantanamine), a clinically used neuroprotectant has been shown to inhibit neuronal apoptosis in a plethora of in vitro and in vivo studies [ 1 – 10 ]....
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- Spring '10
- memantine, NMDA receptor, Cortical Neurons, NMDA Receptor Antagonist