Digging For the Roots of Longevity in Other Species
A logical extension of the metabolic engineering school of longevity science - researchers who seek to slow aging by changing human metabolism - is to find out how extremely long-lived animals manage to be extremely long-lived. Is there something we can learn from their biochemistry that can then be back-ported into the human model via drugs, gene engineering, or other methodologies?
Setting aside my thoughts on the practicality of changing human metabolism to slow aging (hard, complex, worthless for those already old) versus repairing the metabolism we have to reverse aging (less challenging, useful for those already old), I think that the answer is yes, there is much of worth in the varied biochemistries of the animal kingdom:
- Let's Sequence the Exceptionally Long-Lived Mammals
- Naked Mole-Rats and Negligible Senescence
- Ageless Animals, the Lobster Edition
How is it that a whale can resist cancer effectively enough to live for two centuries in the wild, bearing in mind a whale has so many, many more cells than we humans that might become cancerous. How does the construction of naked mole-rat cellular membranes allow them to shrug off oxidative damage and live nine times longer than similar rodent species? Why do lobsters - and possibly some species of clam - seem not to age at all?
A thousand other questions exist. Chris Patil at Ouroboros is thinking along these lines today:
Some species appear not to age, in the sense that they become no more likely to die as time passes - take, for example, Arctic quahogs, the longest-lived animals on record. How does such negligible senescence evolve?...
The first step in understanding the cellular and molecular basis of negligible senescence is to look at factors that are known to influence lifespan in other organisms - oxidized proteins, antioxidant defense systems, heat shock proteins - and see whether any of them show unusual patterns in long-lived animals. Ivanina et al. did just that with the mollusks, looking at aging-related molecular pathways in one clam and one oyster species. Unfortunately, shaking down the "usual suspects" didn't reveal any hints
...
Another possibility is that molluscs are different enough from the more traditional (though less delicious) model organisms of biogerontology that our list of usual suspects won’t be useful - we might need a whole different lineup. Certainly, something is different about particular species of clams, trees, insects and possibly even rodents - it’s up to us to figure out what. The difference between "conventionally" aging species and negligibly senescent ones is one of quality rather than degree, and it may be that the mechanisms explaining (theoretically) infinite lifespans are wholly unrelated to those explaining finite ones. In order to reveal them, we may have to venture outside the warm glow of the lamppost.