Alzheimer's
Researchers have found a way of stimulating the immune systems of mice to fight against amyloid proteins that cause the devastating plaques that are characteristic of Alzheimer's disease. For years scientists have examined the possibility of using a protein-based vaccine to slow the progression of the disease in its early stages. Researchers have created a gene-based vaccine aimed at stimulating the immune systems of mice to potentially fight off plaque-causing amyloid protein in the brain.
Could the same actions that help prevent a heart attack or stroke also prevent or slow the memory loss, confusion and thinking problems of dementia? A new study suggests that for many people, the answer could be yes. And for some, the impact of steps like controlling blood pressure and cholesterol might be greater than the effect of high-priced memory-preserving drugs.
To get a better look at how proteins gather into clusters called amyloid fibrils -- which are associated with important human diseases such as Alzheimer's, Parkinson's and the so-called prion diseases like Mad Cow -- researchers at North Carolina State University decided to make movies. They used a computer simulation technique, discontinuous molecular dynamics, to visualize the meanderings of small proteins called peptides. Movies of the simulation show that 96 randomly placed peptides spontaneously aggregate into what Hall calls a ''sandwich'' of layered protein sheets, similar to the amyloid fibrils discovered in diseased people and animals.
A potent antioxidant abundant in apples and some other fruits and vegetables appears to protect brain cells against oxidative stress, a tissue-damaging process associated with Alzheimer's and other neurodegenerative disorders, according to a new study in rat brain cells conducted by researchers at Cornell University in New York.
The cholesterol-lowering drug atorvastatin slowed down mental decline and improved depressive symptoms in people with Alzheimer's disease, according to a small pilot study reported at the American Heart Association's Scientific Sessions 2004. ''This is the first off-label use of a drug tested in Alzheimer's patients in the last 10 years that has shown promise of benefit.''
Results of laboratory tests by a team from the University of Newcastle upon Tyne found that green and black tea inhibit the activity of certain enzymes in the brain which are associated with memory. The findings, which are published in the academic journal, Phytotherapy Research, may lead to the development of a new treatment for a form of dementia which affects an estimated ten million people worldwide, Alzheimer's Disease.
New findings explaining the complicated process by which the ''energy substations'' of human cells split apart and recombine may lay the groundwork for new treatment approaches to a wide range of diseases, including some cancers and neurodegenerative diseases such as Parkinson's and Alzheimer's.
Certain blood pressure drugs may slow the deterioration of Alzheimer's disease, according to a study published in the October 12 issue of Neurology, the scientific journal of the American Academy of Neurology. Called angiotensin-converting enzyme inhibitors, or ACE inhibitors, the drugs are used to treat high blood pressure. Only ACE inhibitors that can penetrate the blood-brain barrier were shown to have the effect on Alzheimer's. The blood-brain barrier is a natural protective mechanism that shields the brain from foreign substances.
Certain brain changes that are common in normal aging are not the beginnings of Alzheimer's disease. Recent research by cognitive aging experts suggests that changes related to Alzheimer's disease appear in distinct regions of the brain and reflect unique pathology compared with changes that occur in older adults without dementia.
Like estrogen loss in older women, decreased levels of testosterone may put aging men at risk for Alzheimer's disease, according to a new study. The findings bolster sparse research on the adverse effects of age-related testosterone depletion in the brain and may lead to future development of hormone replacement therapies. ''Our findings strongly suggest that normal age-related testosterone depletion is one of the important changes that promote Alzheimer?s disease in men.''
Immunoglobulins which are already being used to treat multiple sclerosis may also be able to help patients with Alzheimer's. This, at least, is the finding of a pilot study on five patients at the University of Bonn. Immunoglobulins contain, among other things, anti-bodies against a protein which is the 'main suspect' thought to trigger off Alzheimer's. After six months of immuno-globulin doses the concentration of this protein in the patients' cerebrospinal fluid was reduced by one third. The patients' cognitive abilities improved slightly.
In a finding that may cause a dramatic shift in the way scientists and researchers search for a therapy for Alzheimer's disease, a team of researchers led by Jeff Johnson, an associate professor at the School of Pharmacy, has discovered that increased expression of a protein called transthyretin in the brain appears to halt the progression of the disease. The findings appear in the current issue of The Journal of Neuroscience. ''This work shows convincingly that if we can intervene in Alzheimer's pathology by introducing molecules and drugs into the brain and increase transthyretin levels, we could slow the progression of the pathology.''
There may be new treatments for stroke, migraine, Alzheimer's and other brain disorders, thanks to the discovery of a mechanism for regulating brain blood flow made by researchers at the University of British Columbia. Scientists found that astrocytes -- cells that surround nerve cells and all blood vessels in the brain -- have a primary role in regulating blood flow within the brain, and hold promise as a target for new therapies.
UCLA neuroscientists have shown for the first time that a diet high in the omega-3 fatty acid DHA helps protect the brain against the memory loss and cell damage caused by Alzheimer's disease. The new research suggests that a DHA-rich diet may lower one's risk of Alzheimer's disease and help slow progression of the disorder in its later stages. ''This is the first proof that our diets affect how our brain cells communicate with each other under the duress of Alzheimer's disease,'' said Greg Cole, senior author and a professor of neurology at the David Geffen School of Medicine at UCLA. ''We saw that a diet rich in DHA, or docosahexaenoic acid, dramatically reduces the impact of the Alzheimer's gene.
When a protein misfolds, the results can be disastrous. An incorrect change in the molecule's shape can lead to diseases including Alzheimer's and Huntington's. But scientists have discovered that misfolded proteins can have a positive side in yeast, helping cells navigate the dicey current of natural selection by expressing a variety of hidden genetic traits. What's more, at the center of this process is a prion, a protein that changes shape in a self-perpetuating way--much like the prion in mammals that is responsible for certain neurological conditions such as Mad Cow disease.
