Blocking Brain Protein Stops Alzheimer's - AND - Watchdog: Cancerous Chemical in Soda

Scientists for the first time explained the role of a protein in the slow destruction of brain cells in Alzheimer’s disease, pinpointing a potential new target for treatments. The protein, called Dkk1, appears in the brains of Alzheimer’s patients at higher levels than in healthy brains. Dkk1 is produced by beta amyloid plaque, a defining feature of the illness, and spurs the breakdown of nerve-fiber connections in the area of the brain linked to learning and memory, scientists at University College London found. People with Alzheimer’s show signs of cognitive decline well before beta amyloid manifests into a detectable build-up of plaque. The researchers were able to identify Dkk1 and block it in mice, raising the possibility of stopping the destruction of brain tissue before irreversible dementia sets in. There is no cure for Alzheimer’s, and approved therapies only mitigate symptoms. “The key thing here is to develop therapies to tackle this molecule before people exhibit a substantial loss of memory,” Patricia Salinas, leader of the study at the University College London’s Department of Cell & Developmental Biology, said in an interview. “That’s the great hope.” Alzheimer's is a degenerative neurological condition with no approved treatment to slow brain-cell death. As many as 5 million Americans have the disease, according to the Centers for Disease Control and Prevention in Atlanta. Using brain slices from mice, scientists monitored how many nerve cells survived in the presence of the antibody that blocks Dkk1 compared with how many survived without the antibody. Brain cells exposed to the antibody remained healthy, with no signs of disintegration, they wrote in the Journal of Neuroscience. Antibodies are molecules produced by the immune system as part of the body’s defenses. The research was funded by Alzheimer’s Research UK, a British dementia research charity, and the Biotechnology and Biological Sciences Research Council. ************************************************************************************* _________________________________________________________________________________ _________________________________________________________________________________ ************************************************************************************* U.S. regulators said soft drinks from PepsiCo Inc and Coca-Cola Co posed no health risk, contrary to a U.S. watchdog group that reported several popular brands contain high levels of a chemical linked to cancer in animals. The Center for Science in the Public Interest (CSPI) said it found unsafe levels of a chemical used to make caramel color in cans of Coca-Cola, Pepsi-Cola, Dr Pepper Snapple Group Inc's Dr. Pepper, and Whole Foods' 365 Cola. The group asked the Food and Drug Administration to ban caramel coloring agents that contain the chemical known as 4-methylimidazole, or 4-MI. This follows a similar plea last year. "Coke and Pepsi, with the acquiescence of the FDA, are needlessly exposing millions of Americans to a chemical that causes cancer," said CSPI executive director Michael Jacobson. The FDA said it was reviewing the group's petition, but the drinks were still safe. "A consumer would have to consume well over a thousand cans of soda a day to reach the doses administered in the studies that have shown links to cancer in rodents," said Doug Karas, an FDA spokesman, in a statement. The cans were all taken from stores in the Washington, D.C. area, and some had levels of 4-MI near 140 micrograms in each 12-ounce can, the watchdog group said. The state of California has a legal limit of 29 micrograms of 4-MI, it added. The FDA's limit for 4-MI in caramel coloring is 250 parts per million (ppm). That caramel would then be diluted when it is put in soda. The highest levels of 4-MI, also known as 4-MEI, found by CSPI were about 0.4 ppm, according to Reuters calculations. "Unlike CSPI, the Coca-Cola Company deals in hard facts," said Coca-Cola spokesman Ben Sheidler in an emailed statement. "Fact: The body of science about 4-MEI in foods or beverages does not support the erroneous allegations that CSPI would like the public to believe. The 4-MEI levels in our products pose no health or safety risks." Sheilder added: "The caramel color in all of our ingredients has been, is and always will be safe. That is a fact." The American Beverage Association said in a statement: "This is nothing more than CSPI scare tactics. In fact, findings of regulatory agencies worldwide ... consider caramel coloring safe for use in foods and beverages."