Syndicate content

Archive - Jul 16, 2011

Date
  • All
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31

New Gene Mutation Discovered for Familial Parkinson’s Disease

Researchers have discovered a new gene mutation they say causes Parkinson's disease. The mutation was identified in a large Swiss family with Parkinson's disease, using advanced DNA sequencing technology. The study, published July 15, 2011, in the American Journal of Human Genetics, was led by neuroscientists at the Mayo Clinic campus in Florida and included collaborators from the U.S., Canada, Europe, United Kingdom, Asia, and the Middle East. "This finding provides an exciting new direction for Parkinson's disease research," says co-author Dr. Zbigniew Wszolek, a Mayo Clinic neuroscientist. "Every new gene we discover for Parkinson's disease opens up new ways to understand this complex disease, as well as potential ways of clinically managing it." The team found that mutation in VPS35, a protein responsible for recycling other proteins within cells, caused Parkinson's disease in the Swiss family. Mutated VPS35 may impair the ability of a cell to recycle proteins as needed, which could lead to the kind of errant buildup of protein seen in some Parkinson's disease brains and in other diseases like Alzheimer's disease, says co-author Dr. Owen Ross, a neuroscientist at Mayo Clinic in Florida. "In fact, expression of this gene has been shown to be reduced in Alzheimer's disease, and faulty recycling of proteins within cells has been linked to other neurodegenerative diseases," he says. So far, mutations in six genes have been linked to familial forms of Parkinson's disease, with many mutations identified as a direct result of Mayo Clinic's collaborative research efforts. Dr. Wszolek has built a worldwide network of Parkinson's disease investigators, many of whom have conducted research at Mayo Clinic. The study's first author, Dr. Carles Vilariño-Güell, and the senior investigator, Dr.

Scientists Discover New Role for Vitamin C in Retina, Posssibly Brain

Nerve cells in the eye require vitamin C in order to function properly — a surprising discovery that may mean vitamin C is required elsewhere in the brain for its proper functioning, according to a study by scientists at Oregon Health & Science University, and collaborators, published in the June 29, 2011 issue of the Journal of Neuroscience. "We found that cells in the retina need to be 'bathed' in relatively high doses of vitamin C, inside and out, to function properly," said Dr. Henrique von Gersdorff, a senior scientist at OHSU's Vollum Institute and a co-author of the study. "Because the retina is part of the central nervous system, this suggests there's likely an important role for vitamin C throughout our brains, to a degree we had not realized before." The brain has special receptors, called GABA-type receptors, that help modulate the rapid communication between cells in the brain. GABA receptors in the brain act as an inhibitory "brake" on excitatory neurons in the brain. The OHSU researchers found that these GABA-type receptors in the retinal cells stopped functioning properly when vitamin C was removed. Because retinal cells are a kind of very accessible brain cell, it's likely that GABA receptors elsewhere in the brain also require vitamin C to function properly, Dr. von Gersdorff said. And because vitamin C is a major natural antioxidant, it may be that it essentially 'preserves' the receptors and cells from premature breakdown, Dr. von Gersdorff said. The function of vitamin C in the brain is not well understood. In fact, when the human body is deprived of vitamin C, the vitamin stays in the brain longer than anyplace else in the body. "Perhaps the brain is the last place you want to lose vitamin C," Dr. von Gersdorff said.