Could a rat hold the key to a longer life?

Scientists working on an experimental anti-ageing therapy claim to have broken a record by extending the lifespan of a lab rat called Sima.

The 47-month-old rat is the last remaining survivor from a group of rodents that received infusions of blood plasma taken from young animals to see if the treatment prolonged their lives.

Sima, a female Sprague-Dawley rat, has outlived her closest rival, who died at the age of 45.5 months, by almost six months. She is now at the centre of much attention as researchers rush to produce and trial therapies based on young blood plasma after experiments found that infusions could reinvigorate ageing organs and tissues.

However, while the studies have found benefits for rodents, there is no evidence that the approach to youthfulness will help humans dodge the passage of time.

The final results will be written up when Sima dies, but, to date, the data gathered suggests that eight rats that received placebo infusions of saline lived for 34 to 38 months. Eight rats that received a purified and concentrated form of blood plasma, called E5, lived for 38 to 47 months, and also had improved grip strength.

Results from such small studies are tentative at best, but some scientists believe the work, and similar efforts by others, has potential.

A preliminary study has found that infusions of young blood plasma wound back the biological clock on rat liver, blood, heart and a brain region called the hypothalamus.

A patent filing on the potential therapy describes how plasma from young mammals is purified and concentrated before use. Some components, such as platelets, are removed, as they can trigger immune reactions.

The patent names pigs, cows, goats, sheep and humans as possible donors. The amount of plasma needed to produce a single concentrated dose is at least as much as the recipient has in their entire body, it states.

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