Posted on 05/01/2003 5:35:52 PM PDT by FairOpinion
The slowdown of the brain with old age is due to the lack of a brain chemical which helps neurons to be selective about what they respond to, reveals research involving the world's oldest monkeys.
Higher brain functions, such as visual recognition or understanding language, require the processing of information in the brain but decline as people get older. This decline appears to be due to a reduction in a neurotransmitter called GABA, say researchers, which means neurons with specific tasks become more easily fired by some other stimulus.
Macaque monkeys, with an age equivalent to 90-years in humans, were not as sharp as their younger counterparts in visual tests despite having perfect eyesight. But when they were given drugs to increase levels of GABA in the brain they improved vastly, say the team.
Delivering GABA calms the neurons down and they become more selective, says neuroscientist Audie Leventhal, at the University of Utah School of Medicine, who led the study. "They look the same as they did 20 years ago," he says.
Importantly, this suggests that mental decline could be easily treated, says Leventhal. "The fact is all the cells are still there and functioning, it's a transmitter problem - it's treatable," he told New Scientist.
Tranquillise and sharpen
The study is the first to show that increasing GABA or its effects can reverse mental decline, says Leventhal. But drugs that boost GABA's effects, such as benzodiazepines, are normally used to tranquillise brain activity not sharpen it.
"It is counterintuitive to say that in order to make Grandpa faster, slow down his brain. Nobody was really thinking about giving tranquillisers to an 85-year-old to perk him up - which is the implication of the study," he says. But he cautions that the team has done no research in human and that people should start taking the drugs themselves.
Peter Tyrer, a community psychiatrist at Imperial College London, thinks the findings are "very interesting and novel". He adds that doctors have sometimes observed a paradoxical effect of benzodiazepine drugs in which rather than calming down, people had become more alert and aggressive.
Making sense
The reason GABA is so important in the brain is that it works as a "gating" mechanism, explains Leventhal. By helping neurons to respond only to specific stimuli, it enables the brain to make sense of the vast quantity of incoming information.
However, as people get older the neurons in their brains increasingly fire non-selectively. Interpreting information then becomes like listening to "whispering in the discotheque as opposed to shouting in a quiet room," Leventhal says.
In the work with the young and old monkeys, his team examined neurons in the part of the brain's vision cortex associated with orientation and shape. He says this is analogous to the region used for vision in humans.
The researchers measured the neuronal responses in monkeys watching computer screens displaying various stimuli, such as moving horizontal lines or flashing dots. Certain neurons should only have been activated in response to specific stimuli - but this was not the case in the oldest monkeys.
When GABA and a GABA-enhancing drug were delivered to the brain cells, the team saw an improvement in the selectivity of neurons in the older animals within a couple of minutes.
Leventhal believes a lack of GABA as people age will not just affect vision but all higher brain functions. The team is now exploring the effects of GABA further and has filed patent applications for this new role of GABA-enhancing drugs in humans.
Journal reference: Science: (vol 300, p 812)
Shaoni Bhattacharya
http://www.msnbc.com/news/907940.asp?0cv=HB10&cp1=1
"Aging brains may be sharpened and, in effect, made young again briefly by increasing the levels of a neurochemical called GABA, a study suggests.
TRANQUILIZERS INCREASE GABA Some tranquilizers, such as Valium, Xanax and Librium, increase the levels of GABA in the brain of human patients. This suggests that these drugs might sharpen aged minds, but that is an idea that first must be carefully tested, Leventhal said. “The idea is counterintuitive,” he said. “The idea that to get grandpa to move faster you have to tranquilize him isn’t something that makes a lot of sense without these results.”
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Interesting. That is not to say that people should rush out and stuff themselves with tranquilizers.
I remember seeing GABA mentioned in some health/nutrition publications. I don't remember, whether it's something you can actually get as a supplement, or get things which turn into GABA in the body, or what normal food items may have it.
But this surely looks very promising, according to the article.
The blood-brain barrier is pretty strict about what gets into the brain. Doubt a dietary supplement would help.
Great place for a typo. I think I might caution the author to start taking the drugs himself.
Gabba gabba, we accept you, we accept you, one of us!
Gabba gabba hey! Gabba gabba hey! Gabba gabba hey!
type louder; my hearing's not what it used to be....
Oh Duh! I almost forgot, it was DABA! DABA! DABA!.
I need some of that GABA stuff. <;-)
As walkingman mentioned in post 4, that while ordinary GABA doesn't cross the blood-brain barrier, but you can get some with some transporter which does. "The "Good" GABA is linked to a lipid soluable 'transporter' (usually hydropyridine)"
This may or may not be worth it to people in general, but if your Mother's condition is specifically related to lack of GABA, I personally would consider trying it.
Human Growth Hormone. It helps rejuvente people in appropriate amounts ( too much is not good for you either).
Most effective taken by injection, but aside from requiring a prescription, it is also very expensive. There are some claims, that by taking certain supplements, you can stimulate your body to make it, but I am personally skeptical about that.
I don't know whether sublingual HGH is really HGH or not, but it's interesting that it produces good results, according to a personal testimony here.
(But anyone considering HGH should check with their doctor, for example, people with diabetes or glucose tolerance problems should not take it, because HGH makes it worse)
For others it is supposed to be helpful in giving more energy, help muscle tone, skin, etc.
But, repeat, anyone considering it should do serious research and check with the doctor, before doing so.
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