X-Message-Number: 14400 Date: Sat, 2 Sep 2000 07:09:54 -0400 From: Thomas Donaldson <> Subject: lifespan experiments with drugs Hi everyone! While the drug isn't given explicitly, there's not much I can say to the note in Cryonet #14394. However ALL readers should know that the discovery of drugs which prolong life by various amounts is hardly new. The main problem with these drugs, which SOME have found important, is that in some cases the prolonged lifespan seemed not to deal with anything essential to aging. However I will point out first that the statistics involved in working out the resulting lifespan with the relatively few animals that attain relatively high ages does not work out as easily as with showing that average lifespan overall does not increase (or put more bluntly, with some of these drugs the fact that no animal lived longer than the normal max lifespan does not prove that the drug did not influence aging: we need many more animals to prove that). Second, a number of different drugs do have experiments showing increases in maximum lifespan. And here is a list: 2-ME, procaine, deprenyl, levodopa, melatonin, dilantin CoQ10, HGH, EGb 761. In some cases the experiments used relatively few animals and (correctly) did not try to work out maximum lifespans. These include pantothenic acid (B5), pyridoxine (B6), and several antioxidants. To repeat: with only a small number of animals and a relatively small effect on lifespan, the maximum lifespans have much less statistical significance than average lifespans. Since the worms used in the above experiment live relatively short lifespans, it may easily be the case that treatments which prolong their lifespans may not work so well on human beings. We have a higher level of natural antioxidants than shorter-lived animals, and that may mean that other factors than simply oxidation may play a bigger role in us than in them. Best wishes and long long life to all, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=14400