科學家：哺乳動物已實現“逆生長” 十年內將進行人體試驗

返老還童是人類永恆的夢想，如今科學家已經向這一夢想邁進了一步，成功實現了老鼠的“逆生長”。科學家表示，進行人體試驗大概需要10年的時間。也就是說，十年以後，人類也將有望實現真正的“逆生長”。

An end to grey hair and crows-feet could be just 10 years away after scientists showed it is possible to reverse ageing in animals.
科學家發現，動物的衰老過程有可能逆轉。從此以後，可能僅需10年，人類就可以告別白髮叢生，滿臉皺紋的命運。

Using a new technique which takes adult cells back to their embryonic form, US researchers at the Salk Institute in California, showed it was possible to reverse ageing in mice, allowing the animals to not only look younger, but live for 30 percent longer.
加利福尼亞索爾克研究所的美國研究員利用一項新技術讓成年鼠細胞重新回到胚胎狀態，向人們展示，在老鼠身上可以實現逆生長，不僅能讓老鼠看上去更年輕，而且還能使其壽命延長30%。

The technique involves stimulating four genes which are particularly active during development in the womb. It was also found to work to turn the clock back on human skin cells in the lab, making them look and behave younger.
該技術會刺激在子宮內發育階段特別活躍的四種基因。實驗發現該技術可以讓人類的皮膚細胞逆齡生長，讓皮膚細胞的狀態更年輕。

Scientists hope to eventually create a drug which can mimic the effect of the found genes which could be taken to slow down, and even reverse the ageing process. They say it will take around 10 years to get to human trials.
科學家們希望最終可以發明與這四種基因具有相同效用的藥，減緩細胞衰老，甚至逆轉衰老的過程。他們表示，進行人體試驗大概需要10年的時間。

"Our study shows that ageing may not have to proceed in one single direction," said Dr Juan Carlos Izpisua Belmonte, a professor in Salk's Gene Expression Laboratory. "With careful modulation, aging might be reversed."
“我們的研究表明，衰老不一定是一個單向的過程，”索爾克基因表現試驗室的專家胡安•卡洛斯•貝爾蒙特博士說道，“通過小心謹慎的調節，衰老的過程可能逆轉。”

"Obviously, mice are not humans and we know it will be much more complex to rejuvenate a person. But this study shows that ageing is a very dynamic and plastic process, and therefore will be more amenable to therapeutic interventions than what we previously thought."
“顯然，老鼠與人類不同，我們知道讓一個人重返年輕要複雜得多。但是該研究表明衰老是一個動態性和可塑性極強的過程，因此要比我們之前認爲的更加經受得住醫療的干預。”

Scientists have known for some time that the four genes, which are known collectively as the Yamanaka factors, could turn adult cells back to their stem cell state, where they can grow into any part of the body.
科學家們對這四種基因的瞭解已有多時，它們被集體稱爲山中因子，可以讓成人細胞重新回到幹細胞的狀態，在這種狀態下，可以分化形成人體的任何部位。

But it was always feared that allowing that to happen could damage organs made from the cells, and even trigger cancer.
但一直令人擔心的是，這樣做可能會損害由這些細胞組成的器官，甚至會引發癌症。

However, it was discovered that stimulating the genes intermittently reversed ageing, without causing any damaging side effects.
然而研究發現，間歇性地刺激這四種基因，逆轉衰老過程，並不會引起任何破壞性的副作用。

In mice with a premature ageing disease, the treatment countered signs of ageing and increased their lifespan by 30 percent. If it worked similarly in humans it could allow people to live until more than 100 years old. In healthy mice it also helped damaged organs to heal faster.
對患有早衰疾病的老鼠進行的治療消除了衰老的跡象，並將它們的壽命延長了30%。如果在人類身上也會產生類似的效果，人們就可能會活到100歲以上。在健康的老鼠身上進行治療有利於較快治癒損壞的器官。

"In other studies scientists have completely reprogrammed cells all the way back to a stem-cell-like state," says co-first author Pradeep Reddy, also a Salk research associate.
“在其他研究中，科學家們已經對細胞進行了完全重組，讓成人細胞重回類似幹細胞的狀態。”共同第一作者兼索爾克助理研究員普拉迪普•雷迪如是說。

"But we show, for the first time, that by expressing these factors for a short duration you can maintain the cell's identity while reversing age-associated hallmarks."
“但我們首次展示了，通過短時間地重組這些因素，你可以既保持細胞的身份，也能逆轉與衰老相關的印記。”

The breakthrough could also help people stay healthier for longer. The ageing population means that the risk of developing age-related diseases, such as dementia, cancer and heart disease also rises. But if the body could be kept younger for longer then it could prevent many deadly diseases for decades.
這一突破可能會有助於人們更加健康，活得更久。人在衰老的同時，患癡呆症、癌症和心臟病等老年疾病的風險也會增高。但是如果身體可以持久地保持年輕狀態，人們就可能幾十年內不得致命性的疾病。