Preclinical Developments

Pathway discovered to influence fat accumulation

Mon, 02 Jul 2007 20:01:39 -0400

In a remarkable breakthrough for weight research, scientists have reported the discovery of a neurochemical pathway that stimulates the accumulation of fat in animals laboring under chronically high stress and exposed to a diet of junk food. Inhibiting the pathway prevented weight gain in mice but selectively spurring the mechanism allowed for the strategic accumulation of weight--potentially opening a new pathway to mold larger breasts, firmer buttocks and younger faces.

Zofia Zukowska of Georgetown University's Department of Physiology and Biophysics led the project, which involved an international team of scientists. Researchers say their work may show that a confluence of high rates of stress and easy access to junk food has led to an epidemic of obesity. Mice in the study were left standing in cold water or exposed to an alpha mouse for part of each day and then offered either a junk food diet or standard feed. The mice receiving high fat diets swiftly added weight. An examination of their fat tissue revealed neuropeptide Y (NPY), a chemical messenger that is produced by the body's nerves. They also had extraordinarily high levels of the far higher levels of neuropeptide Y2R receptor, a molecular partner NPY needs in order to work.

- see the release on their work
- read the article from The Washington Post

ALSO: Mayo Clinic researchers have that the absence of the CD38 gene prevented mice on high-fat diets from gaining weight. Report

Related Articles:
A biologic mechanism for weight gain. Report
Scripps researchers find anti-obesity vaccine. Report
Molecular research points to new obesity therapy. Report
Scientists explore role of PYY in obesity. Report

Heart drug may help memories fade away

Mon, 02 Jul 2007 20:01:39 -0400

The heart drug propranolol can be used to interfere with the way the brain stores memories, offering a new approach to treating people with post traumatic stress disorder, according to a team of U.S. and Canadian scientists. The researchers at McGill and Harvard worked with a group of volunteers with traumatic memories of a crash or rape. They treated the victims with the drugs over a period of 10 days, during which the group related their memories. A week later the volunteers treated with the drug demonstrated fewer physical signs of stress disorder when relating the memory. The theory is that memories are originally in a fluid state and then become hard-wired into the circuitry of the brain. By recalling the memory, they become fluid and malleable again, allowing the drug to interfere with the way the brain stores them. In a separate study at NYU, researchers say they were able to completely eliminate a memory in the brains of rats.

- read the report from the BBC

Prion study points to Alzheimer's therapies

Mon, 02 Jul 2007 20:01:39 -0400

A discovery that the presence of prions interrupts the buildup of beta amyloid may point to new therapies to treat Alzheimer's. The research work was triggered by similarities between human mad cow disease and Alzheimer's. In mad cow disease, corrupted prion proteins cause brain damage. When the level of normal prions is high, the researchers noted, the presence of beta amyloids was low. When the level of prions was low, though, beta amyloids were more prevalent. To test the work, researchers used a mouse model designed to eliminate normal prions. Those mice developed new formations of beta amyloid.

Next researchers will examine whether the aging process interferes with prion proteins' ability to protect people from the build up of beta amyloids. A new therapy that mimics the effects of prions could theoretically be used to stop the development of the disease.

- see the release
- read the BBC's report

Related Articles:
Big pharma sees big payback for Alzheimer's research. Report
Anesthetics can spur brain plaque. Report
Enzyme essential to preventing Alzheimer's. Report
Gene combo dramatically increases risk of Alzheimer's. Report

Venter's latest revelation could save the world

Mon, 02 Jul 2007 20:01:39 -0400

The Times' Anjana Ahuja takes J. Craig Venter's latest revelation and breaks it down to some easily understood concepts. Venter is focused on creating synthetic life, taking 400 or so genes and making a microbe of his own design. Built properly, the microbe could be used to create a new generation of clean fuels. And his patent on the work, if granted, would give Venter control of those products and the vast riches they would produce. But the basic research could also point the way to a new generation of bioterror agents, which could have a dramatically different effect on the planet. Still, the work on life's simplest forms does also highlight the extraordinary collection of 30,000 genes that goes into creating a human.

- see the release on the work
- here's the column from The Times

New compounds in works for tuberculosis

Mon, 02 Jul 2007 20:01:39 -0400

There's new evidence to support the theory that the enzyme protein kinase G offers a promising target in the fight against tuberculosis. The enzyme is secreted by the microbe that triggers TB and is believed to provide essential protection for the bug from the host's immune system, which tracks down and kills most pathogens. Scientists say they have a compound that can block the protein, but were worried about interfering with the action of other proteins also secreted by the microbe. Using X-ray crystallography, the researchers were able to pinpoint the exact method of inhibition and determined that it was unique to that one protein.

"Since we now know exactly what the requirements should be for a good blocker and how to avoid interference with host kinases, we should now be able to rationally design compounds that are highly effective against PknG," said lead author Jean Pieters, a professor of biochemistry at the University of Basle in Switzerland.

- read the report on the TB research from AFP

Related Article:
New compounds combat bacteria's defenses. Report

Disgraced scientist back at work on cloned embryos

Mon, 25 Jun 2007 20:01:39 -0400

In what is shaping up as one of the toughest rehab jobs in science, disgraced Korean scientist Hwang Woo-suk is logging long hours in his new lab. Hwang was accused of one of the biggest frauds in scientific history when he claimed in 2005 to have cloned human embryos and developed embryonic stem cells from them. Hwang apologized for the scam but insisted that he should be allowed to go on with his work. He appears to be doing just that, after he and 30 loyal researchers made the switch from the university to a private lab outside of Seoul. Some experts like Dr. Curt Civin at Johns Hopkins say he just might pull it off--even though his work is likely to get a tremendous amount of scrutiny.

One researcher at the lab says that they have taken stem cells from cloned animal embryos. They believe that they are ready to do the same for human embryos.

- here's the article from The Washington Post

Related Articles:
Magazine retracts discredited paper on embryonic stem cells. Report
Korean scientist faked all evidence of stem cell cloning. Report
S. Korean team to attempt first monkey clone. Report

MIT scientists reverse autism, retardation in mice

Mon, 25 Jun 2007 20:01:39 -0400

Researchers from the Picower Institute for Learning and Memory at Massachusetts Institute of Technology have reversed mild retardation and severe autism in mice by inhibiting the enzyme called p21-activated kinase (PAK). Their study focused on Fragile X Syndrome (FXS)--a leading cause of retardation and autism--which is linked to a mutated X chromosome gene. The PAK enzyme controls the connections between neurons and the brain.

"Strikingly, PAK inhibition also restored electrical communication between neurons in the brains of the FXS mice, correcting their behavioral abnormalities in the process," co-author Susumu Tonegawa, 1987 Nobel laureate and Picower Professor of Biology and Neuroscience, said in a prepared statement. "Notably, due to an elegant genetic manipulation of method employed by the Picower Institute researchers, PAK inhibition in the FXS mice did not take place until a few weeks after appearance of disease symptoms. This implies that future treatment may still be effective even after symptoms are already pronounced."

- read the report from Forbes

Related Article:
Potential breakthrough made for Down syndrome. Report

Nanoparticle developed for new drug delivery system

Mon, 18 Jun 2007 20:01:39 -0400

A scientist at the University of Central Florida has helped develop a nanoparticle that apparently helps deliver high concentrations of medicine for treating glaucoma. The tiny size of the particle allows it to penetrate the blood-brain barrier that typically obstructs therapies. Sudipta Seal, an engineering professor with appointments in UCF's Advanced Materials Processing and Analysis Center and the Nanoscience Technology Center, says that only 1 percent to 3 percent of existing glaucoma therapies actually make it to the eye. Seal's team created a specialized cerium oxide nanoparticle and bound it with a compound that has been shown to block the activity of an enzyme (hCAII) believed to play a central role in causing glaucoma. Nanoparticles would also be less abrasive than complex polymers and this nano approach holds significant promise for use with other therapies.

- see the report on their work

Natural protein used to combat multiple sclerosis

Mon, 18 Jun 2007 20:01:39 -0400

Stanford University scientists have discovered a naturally occurring protein that could be used to treat multiple sclerosis. Injecting alphaB-crystallin into mice with MS, the researchers say they were able to reduce symptoms and cell death while reversing paralysis. Dr. Lawrence Steinman, a professor of neurology and neurological sciences, says that the immune system automatically attacks the protein when it finds it in the brain, even though it's a natural healing agent. "Like a runaway truck careening down a mountain and then having the brakes fall off, the immune attack against alphaB-crystallin worsens the (MS) situation," Steinman wrote.

- check out the report on the project from the CBC

Stem cells used to build new blood vessels

Mon, 18 Jun 2007 20:01:39 -0400

Pointing the way to the development of customized blood vessel grafts for heart and kidney disease, researchers have taken stem cells from muscle tissue to make the blood vessel grafts in rats. The stem cells were allowed to develop on elastic tubes within days of extraction. The researchers were able to seed millions of the stem cells on a tube that was 1.2 mm in diameter. Gaining direction from surrounding tissue on blood pressure and other physical traits, the stem cells formed a mature artery. One distinct plus: these grafts did not develop deadly clots that sometimes occur in other grafts. David Vorp at the University of Pittsburgh School of Medicine says he will next attempt to replicate these results in pigs, which bear a closer physical resemblance to humans.

- read this report on the stem cell research from The Age