Anti-ageing compound set for human trials after turning clock back for mice
  Researchers injected a chemical called nicotinamide adenine
  dinucleotide, or NAD, which reduces in the body as we age.
  The addition of this compound led to the radical reversal
  in the ageing of the mice.

While this is pretty cool, it seems that the most immediate effect would be a higher availability of adenosine triphosphate (ATP), meaning more energy "currency" for the body's machinery to work with [1] [2] (someone please comment if my understanding is incomplete). Used as a general lifestyle drug †, grandma isn't suddenly going to look like a sorority girl, but she may feel like one - a scary thought indeed!Anti-aging technologies are going to introduce many philosophical questions; although, that doesn't quite seem to be the case in this specific instance since this compound will probably just improve the quality of the last couple decades of a person's life rather than drastically extend it. What's the difference between curing disease/prolonging natural life vs unnatural "anti-aging" technologies? At what point do we start grappling with the issues of immortality? Personally, I believe that the mentally-deteriorating effects of everyday life, including what one may call "sin," will be too much for the modern human to retain his/her sanity after a certain point. I for one would rather face death.[1] http://www.genome.jp/dbget-bin/www_bget?C00003[2] http://www.genome.jp/kegg-bin/show_pathway?map00190+C00003† I say "lifestyle drug" here to denote elective treatment, although the effects of natural aging and death dying probably do not fit in the technical definition, which is to treat "non-life threatening and non-painful conditions such as baldness, impotence, wrinkles, erectile dysfunction, or acne"