Alzheimer's drug builds new brain cell connections in rats

A new potential Alzheimer's drug developed at Washington State University helped build new brain cell connections in impaired rats. The drug is drawing notice, in part because it appears to work differently from other treatments.

Principal researchers Joe Harding and Jay Wright say they are pursuing further development of the drug, dubbed Dihexa, through their startup company--M3 Biotechnology--and are also seeking pharmaceutical company development collaborators. Details of the discovery are in The Journal of Pharmacology and Experimental Therapeutics.

Often, the researchers note, drug developers design Alzheimer's treatments to slow cell death or block cholinesterase, an enzyme thought to damage learning and memory in Alzheimer's patients by destroying a crucial neurotransmitter. And drugs tested so far have had mixed results at best, with many, profound disappointments.

The Washington State University research team's approach differs. They developed a drug candidate based on the peptide angiotensin IV that's designed to reverse learning deficits in Alzheimer's or other forms of dementia rather than simply stop the decline. Among their assertions: The drug can cross the blood-brain barrier and can be taken in pill form.

For their trial, the research team tested their drug on rats with Alzheimer's-like mental impairment created by the chemical scopolamine (it jams up a neurotransmitter involved with both learning and memory). The drug, taken orally or by injection, helped reverse befuddlement so the rats could learn the location of a submerged platform in a water tank. Interestingly, the team obtained similar but more moderate results testing on older rats. Overall, however, they believe that Dihexa was much stronger than brain-derived neurotrophic factor (BDNF) in creating new neuronal connections. BDNF drops in the brains of Alzheimer's patients.

While the results are promising in rats, they don't guarantee success down the line. The researchers must verify that it is safe with subsequent testing in more animals and in people. But they must also confront the risk that positive results in rodents may not be repeatable in human trials, which are likely years away. Still, they are pushing ahead, with more studies to come, pending new funding or partnerships.

- read the release
- here's the journal abstract