diabetes and capsiacin

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(forwarded from my SCA-biologist list..)

 

Diabetes breakthrough

Toronto scientists cure disease in mice

 

Tom Blackwell, National Post

Published: Friday, December 15, 2006

 

In a discovery that has stunned even those behind it, scientists at a

Toronto hospital say they have proof the body's nervous system helps

trigger diabetes, opening the door to a potential near-cure of the

disease that affects millions of Canadians.

 

Diabetic mice became healthy virtually overnight after researchers

injected a substance to counteract the effect of malfunctioning pain

neurons in the pancreas.

 

" I couldn't believe it, " said Dr. Michael Salter, a pain expert at

the Hospital for Sick Children and one of the scientists. " Mice with

diabetes suddenly didn't have diabetes any more. "

The researchers caution they have yet to confirm their findings in

people, but say they expect results from human studies within a year

or so. Any treatment that may emerge to help at least some patients

would likely be years away from hitting the market.

 

But the excitement of the team from Sick Kids, whose work is being

published today in the journal Cell, is almost palpable.

 

" I've never seen anything like it, " said Dr. Hans Michael Dosch, an

immunologist at the hospital and a leader of the studies. " In my

career, this is unique. "

 

Their conclusions upset conventional wisdom that Type 1 diabetes, the

most serious form of the illness that typically first appears in

childhood, was solely caused by auto-immune responses -- the body's

immune system turning on itself.

 

They also conclude that there are far more similarities than

previously thought between Type 1 and Type 2 diabetes, and that

nerves likely play a role in other chronic inflammatory conditions,

such as asthma and Crohn's disease.

 

The " paradigm-changing " study opens " a novel, exciting door to

address one of the diseases with large societal impact, " said Dr.

Christian Stohler, a leading U.S. pain specialist and dean of

dentistry at the University of Maryland, who has reviewed the work.

 

" The treatment and diagnosis of neuropathic diseases is poised to

take a dramatic leap forward because of the impressive research. "

 

About two million Canadians suffer from diabetes, 10% of them with

Type 1, contributing to 41,000 deaths a year.

 

Insulin replacement therapy is the only treatment of Type 1, and

cannot prevent many of the side effects, from heart attacks to kidney

failure.

 

In Type 1 diabetes, the pancreas does not produce enough insulin to

shift glucose into the cells that need it. In Type 2 diabetes, the

insulin that is produced is not used effectively -- something called

insulin resistance -- also resulting in poor absorption of glucose.

 

The problems stem partly from inflammation -- and eventual death --

of insulin-producing islet cells in the pancreas.

 

Dr. Dosch had concluded in a 1999 paper that there were surprising

similarities between diabetes and multiple sclerosis, a central

nervous system disease. His interest was also piqued by the presence

around the insulin-producing islets of an " enormous " number of

nerves, pain neurons primarily used to signal the brain that tissue

has been damaged.

 

Suspecting a link between the nerves and diabetes, he and Dr. Salter

used an old experimental trick -- injecting capsaicin, the active

ingredient in hot chili peppers, to kill the pancreatic sensory

nerves in mice that had an equivalent of Type 1 diabetes.

 

" Then we had the biggest shock of our lives, " Dr. Dosch said. Almost

immediately, the islets began producing insulin normally " It was a

shock ? really out of left field, because nothing in the literature

was saying anything about this. "

 

It turns out the nerves secrete neuropeptides that are instrumental

in the proper functioning of the islets. Further study by the team,

which also involved the University of Calgary and the Jackson

Laboratory in Maine, found that the nerves in diabetic mice were

releasing too little of the neuropeptides, resulting in a " vicious

cycle " of stress on the islets.

 

So next they injected the neuropeptide " substance P " in the

pancreases of diabetic mice, a demanding task given the tiny size of

the rodent organs. The results were dramatic.

 

The islet inflammation cleared up and the diabetes was gone. Some

have remained in that state for as long as four months, with just one

injection.

 

They also discovered that their treatments curbed the insulin

resistance that is the hallmark of Type 2 diabetes, and that insulin

resistance is a major factor in Type 1 diabetes, suggesting the two

illnesses are quite similar.

 

While pain scientists have been receptive to the research,

immunologists have voiced skepticism at the idea of the nervous

system playing such a major role in the disease. Editors of Cell put

the Toronto researchers through vigorous review to prove the validity

of their conclusions, though an editorial in the publication gives a

positive review of the work.

 

" It will no doubt cause a great deal of consternation, " said Dr.

Salter about his paper.

 

The researchers are now setting out to confirm that the connection

between sensory nerves and diabetes holds true in humans. If it does,

they will see if their treatments have the same effects on people as

they did on mice.

 

Nothing is for sure, but " there is a great deal of promise, " Dr.

Salter said.

 

 

for article, click link...

 

http://tinyurl.com/yxo3bt

 

Cynthia