The title of this book,” How Selegiline Slows Brain Aging “, certainly stirs my interest. However as indicated above, this book is really a summary of Prof. Knoll’s  distinguished career relating  selegiline to depression, Alzheimer's disease, and Parkinson's disease. This is in the context of his ingenious basic work.

In particular, the idea that selegiline, alias ((-)deprenyl), this specific MAO B inhibitor, has an even more important role as a Catecholamine Activity Enhancer was news to me. However, a PubMed review indicates that for the past 20 years this notion has been the exclusive property of the Hungarians and the Japanese, but has little intellectual traction in the USA. Peculiar.

Obviously, conducting a  life extending trial in humans is a far from easy task. Almost all of the longevity studies that Knoll lists use rats or mice, although there is a study each of Syrian hamsters, Beagle dogs, and Drosophila.

Interestingly, the early studies were primarily devoted to studies of sexual functioning, using this as a surrogate for striatal functioning. The effects on longevity seem quite substantial."In the saline-treated group (n = 66) the last signs of sexual activity vanished to the 33rd week of treatment. (-)Deprenyl treatment restored full scale sexual activity in 64 out of 66 rats. The longest living rat in the saline-treated group lived 164 weeks. The average lifespan of the group was 147.05 +/- 0.56 weeks. The shortest living animal in the (-) deprenyl-treated group lived 171 weeks and the longest living rat died during the 226th week of its life. The average lifespan was 197.98 +/- 2.36 weeks, i.e. higher than the estimated maximum age of death in the rat (182 weeks). This is the first instance that by the aid of a well-aimed medication, members of a species lived beyond the known lifespan maximum".  Other studies showed that rodents with a naturally low sexual drive do not live as long as the high functioning group, but that this difference is remedied by selegiline.

There is some peculiar problem here, probably due to economics and patent rights, although I don’t rule out the endemic narrow focus on molecular biology.  One would think that a group of drugs that possibly lead to living longer, while preserving sexual potency, would have substantial appeal. Certainly, the lack of clinical sexual investigation of Selegiline--which has the virtue of being on the American market is surprising--in fact dumfounding.

Donald F. Klein

April 3, 2014