Pubdate: Sat, 19 Apr 2003
Source: Hamilton Spectator (CN ON)
Copyright: The Hamilton Spectator 2003
Contact:  http://www.hamiltonspectator.com/
Details: http://www.mapinc.org/media/181
Author: Jeremy Laurance, The Independent, London
Bookmark: http://www.mapinc.org/pot.htm (Cannabis)
Bookmark: http://www.mapinc.org/mmj.htm (Cannabis - Medicinal)

MARIJUANA MAY SLOW EFFECTS OF AGING

Cannabis, the third most popular recreational drug after alcohol and 
tobacco, could become as widely used as Aspirin in the 21st century.

There is growing evidence that its compounds may protect the brain against 
the damaging effects of aging.

Although the drug distorts perception and affects short-term memory, it may 
also help prevent degenerative diseases such as Alzheimer's, Parkinson's, 
Huntington's and motor neurone diseases.

Scientists at the Institute of Neurology in London, say the "huge 
potential" of cannabis compounds is emerging, as understanding of its 
biological and pharmacological properties improves.

Professor Alan Thompson and his colleagues wrote in Lancet Neurology:

"Basic research is discovering interesting members of this family of 
compounds that have previously unknown qualities, the most notable of which 
is the capacity for neuroprotection."

The results of two trials in patients with multiple sclerosis (MS) are 
expected this summer and the first cannabis-based medicines are being 
considered for licensing.

None of them will have the psychoactive properties of the raw drug when 
smoked or ingested.

Thompson's team says: "Even if the results of these studies are not as 
positive as many expect them to be, the fact that we are only just 
beginning to appreciate the huge therapeutic potential of this family of 
compounds is clear."

Cannabis was thought to affect the cells like alcohol by seeping through 
the cell membrane. But in 1990 the first cannabinoid receptor was found, 
which revolutionized the study of cannabinoid biology.

The discovery revealed an endogenous system of cannabinoid receptors, 
similar to the opioid system, to which the drug bound when it was ingested.

Just as endorphins are the body's natural equivalent of heroin, a fatty 
acid called anandamide (Sanskrit for "inner bliss") is the natural 
equivalent of cannabis.

The natural system of cannabinoid receptors plays a role in maintaining the 
balance of chemicals in the brain, which regulate the rate at which neurons 
fire.

By altering this system, scientists believe it may be possible to slow or 
prevent the process of brain decay.

David Baker, lead author of the Lancet review and senior lecturer at the 
Institute of Neurology, said: "Alzheimer's disease is the result of very 
slow degeneration caused by the death of nerve cells. We probably don't see 
symptoms until 30 to 40 per cent of the nerve cells have died.

"Something regulates this decay and if we could slow it by even a small 
fraction we might delay by a decade the point where someone loses their 
memory."

But cannabis is a double-edged sword, with potentially damaging side effects.

"It may be possible to develop drugs that allow selective targeting of 
different areas of the brain and spinal cord and there may be a way of 
limiting the negative effects," Baker said.

A study by Baker and colleagues, in which the natural system of cannabinoid 
receptors was removed in mice, showed that the rate of nerve loss was 
increased, indicating its role in preserving brain function. The study, 
accepted for publication in a medical journal, "really clinches the 
argument," Baker said.

He added: "Cannabis has gone from the drawing board into trials in record 
time, largely because of patient pressure. Hopefully it will work and be 
acceptably safe."
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MAP posted-by: Jackl