For more than a decade, Hans-Ulrich Demuth and his team at a small biotech firm in eastern Germany had been researching protein deposits in the brain, deposits that have long been associated with Alzheimer's disease.

“Our question was what are the harmful components of the protein deposits, and is there a way to reduce or eliminate them by blocking the enzyme we know is part of its characteristics?" Demuth said.

As it turns out, there was.

Demuth's team at Probiodrug found the enzyme that was responsible for an extremely small, but extremely harmful part of the deposits. It's known as Glutaminyl Cyclase (QC) and the researchers devised a method they believed would block its function in lab mice.

Stunning results

Stefan Rossner of the Paul Flechsig Institute at the University of Leipzig was contracted to study the brains of the mice. He discovered stunning results.

"The protein deposits typical of Alzheimer's disease were reduced in the brains of the mice by up to 80 percent," he said.

Dirk Montag of the Leibniz Institute for Neurobiology in Magdeburg sought to find out the practical results of the reduced instance of protein deposits, performing behavioral and cognitive tests on the mice.

"In general performance, reflexes and the like, the treated mice were the same as the untreated control mice," he said, adding, "with the exception of mental functioning, that is, which was improved."

Montag also said that he had found no behavioral side effects.

If success on that scale were to be repeated in human trials, the discovery could prove to be a very big one.

Alzheimer's is the most common form of dementia and is triggered when nerve cells in the brain die. Up to a million people in Germany are estimated to be afflicted by the disease which remains incurable and causes loss of memory, orientation and recognition.

Scientists plan a new study to monitor potential side effects more closely. But the results of this study are nothing sort of a sensation. The treatment given to the mice to inhibit the QC enzyme reduced not just the particularly harmful matter within protein deposits in brain cells, rather the size and instance of protein deposits altogether.

Holding back from 'breakthrough'

The finding has many in the research community excited, and has earned the study's results a place in the respected journal Nature Medicine. But some say the treatment still has much to prove.

Lutz Froehlich of Mannheim's Central Institute of Mental Health told the Associated Press that he believed a causal relationship between protein deposits and the death of neural cells had yet to be established. Any treatment that focuses on the deposits may end up missing the target of keeping brain cells alive, he said.

Of the positive results in cognitive tests of the learning capabilities of the mice, Froehlich said, "Animal models can never provide us the whole picture of a disease's effects, just isolated aspects." He added that he'd seen too many studies with great results from animal testing produce underwhelming results from humans.

Human testing on its way

The researchers' next challenge will be to take what they know and develop a treatment suitable for humans -- that is, one that is both non-toxic and still effective at blocking the enzyme.

Demuth said, however, that getting toward such a compound shouldn't take more than a year.

While there's no telling as to whether the enzyme blocker will work nearly as well on humans as on mice, Demuth was hopeful, saying he thought that "the generations that are now 30, 40, or 50 years old should definitely benefit from this discovery."

If tests do succeed, researches say a legitimate anti-Alzheimer's drug could be available to the public within five to eight years.