Up to now, stem cell-based interventions (SCBI)

have still been in an immature state. Only a few trials are currently under way, and are so far mostly in a preclinical phase. Current focuses include Duchenne’s disease, Parkinson s disease, and Alzheimer’s disease.1 The major concept of all these experiments is to create Inhibitors,research,lifescience,medical a treatment scheme similar to that in bone-marrow diseases where hematopoietic stem cells are regularly used as a cure for certain types of leukemia – in this case, the issue of the appropriate stem cell type used has been solved. For SCBI in neurodegenerative disease there is an ongoing debate Selleckchem Paclitaxel regarding which cell type might be suitable for transplantation – embryonic versus fetal versus adult stem cells. Furthermore, the question of stem-cell Inhibitors,research,lifescience,medical homing needs to be addressed, since one may not need to transplant the cells by neurosurgical procedures. Instead, it could be sufficient to inject these

cells into the cubital vein only,2 since the plasticity of these cells enables them to find the niche where they are needed – even within the central nervous system (CNS). Apart from technical aspects, ethical problems arise. Inhibitors,research,lifescience,medical Even without touching on the debate of using human embryonic stem cells, there is plenty of groundwork for bioethicists to do. When the ethical and technical issues have been resolved, we may proceed from neurodegenerative to psychiatric illnesses such as affective disorders and schizophrenia. We still face a substantial lack of proof as to whether Inhibitors,research,lifescience,medical these psychoses are the cause or the correlate of disturbed adult neurogenesis.3 If so, we may consider these severe illnesses as being neurodegenerative,

as there is some compelling data for this, at least in the field of depression. Inhibitors,research,lifescience,medical There may be some clinical trials of grafting stem cells, in a long and cumbersome process, into the brains of diseased patients. In our opinion, this will only be the case for very severe cases of depression, after having tried nearly all the available medication options and from unsuccessful electroconvulsive therapy (ECT). Past and current status In the past, psychiatric diseases have been treated pharmacologically with broad-profile medication – the socalled “shotgun method.” In the same way that a shotgun fires many pellets at once, psychiatric medication can impact on many different neurotransmitter systems. Due to this profile, many of these drugs, such as tricyclic antidepressants (TCAs) or first-generation antipsychotics (FGAs) caused severe undesirable side effects, which were held responsible for poor compliance and discontinuation of the prescribed medication. During the last two decades, new drugs have surfaced with fewer shotgun side effects because of their particular pharmacodynamic design targeted against one single and very specific molecule.