I have a grand daughter, who is just about 4 years old. She obviously has absolutely no knowledge about life or death. Yet she finds nothing wrong with the facts that old people look wrinkled, weak and hunch backed or eventually they are likely to die. She seems almost nonchalant about the entire aging process and thinks unemotionally about it as a matter of fact. Most of us, as adults, surprisingly have the same attitude towards old age and death; as long as the subject is someone else. But when somewhere in our forties, the first signs of aging, such as menopause or diabetes or high cholesterol hit us, our nonchalant thinking undergoes a rapid change and we get scared for the first time of the old age and eventual death.
Much later, after crossing sixties or seventies, most of us accept it as a fact of life and try to cope up with it, in our individual ways. We still remain scared of death. However, the fear is no longer about the inevitability of loss of our one’s own life: now it is mostly centered about the last painful days, months or years of mental or physical debility and how best it could be avoided
The concept that aging is an uncontrolled natural process set up or triggered by nature in our bodies is being challenged by a group of scientists led by Professor Dongsheng Cai, at Albert Einstein College of Medicine in the United States. Writing in the journal Nature, Prof. Cai and others claim that their research has led them to, what appears to be the body’s control centre for aging. They suggest that it is the body that in fact controls the aging instead of aging occurring independently in the body’s various tissues.
In a series of experiments, the researchers found they could extend the lives of mice by a fifth, without the animals suffering from muscle weakness, bone loss or memory problems common in old age. They claim that they have found a biological command centre for the aging process in a lump of brain the size of a nut. This mechanism is identified in the hypothalamus portion of brain, which sits deep inside the brain. In fact the hypothalamus area of the brain controls many key functions of the body like hunger, thirst, body temperature and fatigue.
When we grow old, the first changes that occur is an increase in inflammatory changes in various tissues of the body. Prof Cai says that: “Inflammation is also involved in various age-related diseases, such as metabolic syndrome, cardiovascular disease, neurological disease and many types of cancer,” he suspects that the hypothalamus might also play a key role in aging through the influence it exerts throughout the body and it could be the real fountain of aging.
To find out how the hypothalamus might be affecting the aging process, they decided to study hypothalamic inflammation by focusing on one protein complex. Prof Cai says that “Inflammation involves hundreds of molecules, and this one sits right at the centre of that regulatory map.” He and his team have now proved that activating the protein complex pathway in the hypothalamus of mice significantly accelerated the development of aging, as shown by various physiological, cognitive and behavioural tests. The mice showed a decrease in muscle strength and size, in skin thickness, and in their ability to learn – all indicators of aging and shortened life span. In a reverse process blocking a pathway in the hypothalamus increased longevity in mice by about 20 per cent.
The scientists also found that activating the pathway in the hypothalamus causes declines in levels of gonadotropin-releasing hormone (GnRH), which is made in the hypothalamus. Suspecting that reduced release of GnRH from the brain might contribute to whole-body ageing, the researchers injected the hormone into aged mice and made the striking observation that the hormone injections protected them from the impaired neurogenesis – creation of new neurons – associated with aging. When aged mice received daily GnRH injections for a prolonged period, the therapy exerted benefits that included the slowing of age-related cognitive decline.
Prof. Cai writes in his article in the magazine Nature:
“They found that a chemical called NF-kB became more active in the hypothalamus of mice as they got older. When the researchers blocked the substance mice lived up to 1,100 days, compared with 600 to 1,000 days for normal healthy mice. When they boosted NF-kB in mice, they all died within 900 days. Further work showed that NF-kB lowered levels of a hormone called GnRH, which is better known for the central role it plays in fertility and the development of sperm and eggs. When the scientists gave old mice daily jabs of GnRH they found that this, too, extended the animals’ lives, and even caused fresh neurons to grow in their brains. “
According to Professor Cai, preventing the hypothalamus from causing inflammation and increasing neurogenesis via GnRH therapy are two potential strategies for increasing lifespan and treating age-related diseases.
This research is certainly going to open new lines of thinking and treatment of life threatening diseases such as metabolic syndrome, cardiovascular disease, neurological disease and many types of cancer for patients of young age. Most of us, including me, might not understand the technicalities of this report, but that is hardly necessary to get the message. Still, I feel that there may not be many takers for increasing the life span by undergoing this treatment. If you ask anyone in his seventies and eighties and who has lived a fairly normal life, a question whether he or she wants to live longer; the chances are that for majority of the people, the answer is likely to be negative. Who really wants to live longer?
Definitely not me!
I found some very interesting readers comments on the news of this new discovery. Here are few examples, which according to me are perhaps typical of thinking of people.
You only go through life once and if you work it right ,once is enough!
– Jack , London,
What’s this, a longer life of cynicism and work? I’d rather not. Death isn’t a punishment; it’s a reward.
– F.Petrov , Novosibirsk
Stop tampering with nature already!
– Mrs Cullen, A town afar
Sleep a little less, eat a lot less, drink less, smoke less, laugh more. There’s your 20% lifespan increase right there. Or perhaps a wiser person would accept the continuity of existence, and do more with the time they have left..? I’ll have another smoke and think about that one….
– Sensei , Surrey
(First published in Akshardhool on 4th May 2013)