Antiapoptotic effects of the peptidergic drug cerebrolysin on primary cultures of embryonic chick cortical neurons.
Cerebrolysin (EBEWE Arzneimittel, Austria, Europe) is a widely used drug relieving the symptoms of a variety of neurological disorders, particularly of neurodegenerative dementia of the Alzheimer's type. It consists of approximately 25% of low molecular weight peptides (<10k DA) and a mixture of approximately 75% free amino acids, this being based on the total nitrogen content. In this study we used a low serum (2% serum supplement) cell stress in-vitro model to assess drug effectiveness on neuronal viability and programmed cell death (PCD). In this in-vitro model the type of cell death was previously shown to be primarly apoptotic, which was verified by DNA-laddering and TUNEL-staining. For evaluation of neuronal viability a MTT-reduction assay was performed after 4 DIV and 8 DIV and the percentage of apoptotic neurons was determined by bis-benzimide staining of nuclear chromatin. To differentiate between possible effects of the free amino acids and the peptide fraction of Cerebrolysin an artificial amino acid mixture (AA-mix) was used as a control. Cerebrolysin, the AA-mix and 10% foetal calf serum (FCS) caused a similar increase in viability after 4 DIV, whereas the effects of the growth factors BDNF and FGF-2 were less pronounced. After 8 DIV Cerebrolysin, but not the AA-mix, was able to ameliorate neuronal viability, which could reflect a neuro-protective effect or an increased activity of the mitochondrial dehydrogenase measured in a MTT-reduction assay. The percentage of cells showing apoptotic chromatin changes was significantly reduced (p < 0.01) in cultures treated with Cerebrolysin, whereas the AA-mix failed to decrease the percentage of cells showing apoptotic chromatin changes. These findings ascertain an anti-apoptotic effect of the peptide fraction of Cerebrolysin and reveal a transient viability promoting effect of the amino acid fraction, which is most likely due to improved nutritional supply.
Hartbauer
M
M
Institute of Zoology, Department of Neurobiology, Karl-Franzens University, Graz, Austria. harbaue@e-mail.kfunigraz.ac.at
Hutter-Paier
B
B
Skofitsch
G
G
Windisch
M
M
D000596:Amino Acids / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001798:Blood Proteins / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D020287:In Situ Nick-End Labeling; D009474:Neurons / Q000166:cytology* / Q000187:drug effects; D018696:Neuroprotective Agents / Q000494:pharmacology*
D000596:Amino Acids; D001798:Blood Proteins; D018696:Neuroprotective Agents; C006952:cerebrolysin