Alzheimer’s study on mice promising

By Elizabeth Allen – Express-News

Rapamycin, which drew attention last summer for extending the lives of mice, now is showing promise in treating mice with the mouse equivalent of Alzheimer’s.

Mice with human genes that developed Alzheimer’s symptoms were able to learn and remember as well as normal mice when fed the drug, according to a University of Texas Health Science Center study published Feb. 23 in the Journal of Biological Chemistry.

The new study, led by physiology Professor Salvatore Oddo, is one of nine offshoots from a study that extended the lives of female mice by 14 percent and of males by 9 percent. Those results, produced by the health science center’s Barshop Institute for Longevity and Aging Studies and two other labs, were published in July in the journal Nature.

The normal mouse life span is up to 24 months. The experiment began when the mice were 6 months old, just beginning to develop the lesions associated with Alzheimer’s, Oddo said.

The 57 mice were drilled four times a day, five days a week, on learning and memory. Researchers used a mouse-sized heated swimming pool with a small platform in part of it, just below the surface where the mice couldn’t see it. They then placed a couple of visual cues around the pool to help the mice orient themselves.

Since mice don’t like water, even warm water, they swam around looking for a way out until they bumped into the platform. After the mice climbed up on it, researchers left them there a few seconds to look around and see the visual cues before plucking them out and warming them on a heating pad.

“We try to keep the stress as low as possible, because that may alter the results,” Oddo said.

After four or five days of drills, normal mice swam straight to the platform. The mice with the Alzheimer’s-like brains that were given rapamycin did as well as the normal mice, Oddo said, reversing the Alzheimer’s-like effects.

The normal mice that were given rapamycin, however, did no better than the normal mice that had none, Oddo said.

After that, “we sacrifice the mice and we take their brains out,” Oddo said. Brains of the transgenic mice that ate rapamycin had fewer and smaller lesions than the transgenic mice that had none.

What that may mean for humans will require further research.

“A mouse is a mouse, of course,” Oddo said. “How much you can extrapolate that to humans depends on who you talk to.”

Alzheimer’s advocates also warned that the results are preliminary.

Whenever a new study hits the news, relatives of Alzheimer’s patients start calling, said Ginny Funk, spokeswoman for the regional chapter of the Alzheimer’s Association.

“We know that truly the only thing that is going to stop this dreadful disease is research,” Funk said, “but we also have to explain to families that it can also take a long time.”

Oddo has launched his next study, raising 80 mice to the age of 15 months, when the Alzheimer’s-like symptoms would be more advanced, and researchers will try to understand exactly how the rapamycin helps the mouse brain.

Rapamycin, which was originally discovered in soil from Easter Island, is used as an immune-suppression drug to help people’s bodies accept organ transplants. The original Barshop Institute longevity study, led by molecular medicine Professor Dave Sharp and pharmacology Professor Randy Strong, was listed as a runner-up for “breakthrough of the year” by Science Magazine and garnered the health science center a $5.2 million federal stimulus grant to fund a cascade of follow-up studies on rapamycin.

SOURCE: mysanantonio.com