Posts tagged biology

I’ve been reading up on biology recently—molecular biology as it relates to cancer and aging, in particular.  I haven’t shared much about it, because I was busy getting myself up to speed for quite a while.  Today I came across an interesting aging article published a few months ago that I guess didn’t quite make it up to the mainstream press, so I thought I should share.

A group in Austria succeeded in extending the lifespan of yeast (both chronological and replicative), flies, worms, and some human lab cells with a new chemical, spermidine.  It sounds like it’s the first one to work so widely after resveratrol and rapamycin, both widely reported in the media in the last couple of years. It extends lifespan around 10-20%, on the order of but in a bit different conditions than caloric restriction.

Taken from the writeup by Matt Kaeberlein (one of the top couple dozen aging folks I keep an eye on) in Nature Cell Bio News (the mainstream media if you’re a cell biologist): His summary:

Identifying therapies to slow down ageing and delay age-associated diseases is a primary goal of ageing-related research. Resveratrol and rapamycin were first found to promote longevity in yeast, and their effects were then extended to several organisms. Spermidine is a new longevity drug that can increase life span in yeast, nematodes and flies, possibly through an effect on chromatin-mediated regulation of gene expression.

His conclusion paragraph:

What is the potential relevance of this study for human ageing? Clearly, if spermidine is found to increase life span or health span in rodents, it will join rapamycin and resveratrol as a leading candidate for treating age-associ- ated diseases in people. Of these, rapamycin is currently the only one known to enhance mouse longevity, but there are concerns that rapamycin may be of limited therapeutic value due to detrimental side effects such as immunosuppression13. No such side effects are known for spermidine. In addition, sper- midine is a natural component of our diet, and several foods are known to be rich in spermi- dine, including soy beans, tea leaf, and mush- rooms. Evidence suggests that eating a diet rich in spermidine results in increased blood spermidine levels14. Thus, it could be relatively easy for most people to obtain the benefits of spermidine through dietary modifications or by supplementation. However, there may be a darker side to spermidine with respect to mammalian ageing: oxidation of polyamines causes oxidative stress that can induce cell death, and high levels of polyamines are asso- ciated with malignancy15. Indeed, chemical inhibitors of polyamine metabolism are being studied as potential anti-cancer agents15. Thus a better understanding of the mechanistic details that underlie the pro-longevity effects of spermidine in simple eukaryotes, as well as careful long-term studies of dietary sup- plementation with spermidine in mammals, are needed before such a strategy should be pursued in humans.

The paper itself is here, behind the nature firewall: http://www.nature.com/ncb/journal/v11/n11/abs/ncb1975.html

Kaeberlein’s write-up is here, also behind the firewall: http://www.nature.com/ncb/journal/v11/n11/full/ncb1109-1277.html

As always, if you ever want any articles I reference and you can’t get access, just ask and I’ll help.

A final note: It has not escaped this author’s attention that spermidine supplementation may get a big boost just from the ridiculous name of the chemical.