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Posts Tagged ‘alzheimer’s’

Families shed light on likely causative gene for Alzheimer’s

The genetic profile of two large Georgia families with high rates of late-onset Alzheimer’s disease points to a gene that may cause the disease, researchers say.

Genetic variations called single nucleotide polymorphisms, or SNPs, are common in DNA, but this pattern of SNPs shows up in nine out of 10 affected family members, says Dr. Shirley E. Poduslo, neuroscientist in the Medical College of Georgia Schools of Medicine and Graduate Studies and the Charlie Norwood Veterans Affairs Medical Center in Augusta. … Continue Reading »

Model shows how mutation tips biochemistry to cause Alzheimer’s

Your fate can be determined by tiny events. Imagine you live in the city and you walk everywhere to get exercise – you are healthy and not afraid of getting mugged. You almost never eat breakfast so you don’t stop at the donut shop on the way to work, until one day the manager replaces the girl at the counter with her pretty red-haired younger sister. This seemingly unimportant change in your world is just enough to overcome your ability to resist high-fat temptation. A million donuts later, your cholesterol level surges and then your heart gives out. Curse you, little red-haired girl!

Like staff change at the donut shop, subtle, seemingly inconsequential differences in human genetic design can lead to some unexpected tipping points in cellular chemistry that can lead to disaster. Cellular processes, like all the routines of life, are unfathomably complex, constantly evolving, and are sometimes dramatically sensitive to the smallest of changes. Consider the case of Alzheimer’s disease… … Continue Reading »

Seeing Alzheimer’s amyloids

A-beta Peptide FibrilIn an important step toward demystifying the role protein clumps play in the development of neurodegenerative disease, researchers have created a stunning three-dimensional picture of an Alzheimer’s peptide aggregate using electron microscopy. The study, in this week’s issue of the Proceedings of the National Academy of Sciences, reports that researchers from Brandeis University in Waltham, Mass., and the Leibniz Institut in Jena, Germany, have shown—for the first time—how A-beta peptide, found in the brains of Alzheimer’s patients, forms a spaghetti-like protein mass called an amyloid fibril.

“This study is a significant advance regarding our understanding of how these fibrils are built from the A-beta peptide (Alzheimer’s peptide),” said co-author Nikolaus Grigorieff, a biophysicist at Brandeis University and an investigator with the Howard Hughes Medical Institute. “People have been guessing for decades what these fibrils look like, but now we have an actual 3D image.” … Continue Reading »

Ground-breaking new insight into the development of Alzheimer’s disease

According to estimates there are 85,000 Alzheimer patients in our country and approximately 20,000 new cases every year. This spectacular increase is due to the increasing aging population. Unfortunately it is still unclear precisely which aging process forms the basis of this spectacular rise in the occurrence of the disease. VIB scientists affiliated to K.U.Leuven have discovered an important molecular link between Alzheimer’s disease and the development of the typical plaques in the brains of Alzheimer patients. This discovery is an important breakthrough in the fundamental research into the cause of Alzheimer’s disease. … Continue Reading »

Vitamin E may help Alzheimer’s patients live longer

People with Alzheimer’s disease who take vitamin E appear to live longer than those who don’t take vitamin E, according to research that will be presented at the American Academy of Neurology 60th Anniversary Annual Meeting in Chicago, April 12–19, 2008.

For the study, researchers followed 847 people with Alzheimer’s disease for an average of five years. About two-thirds of the group took 1,000 international units of vitamin E twice a day along with an Alzheimer’s drug (a cholinesterase inhibitor). Less than 10 percent of the group took vitamin E alone and approximately 15 percent did not take vitamin E.

The study found people who took vitamin E, with or without a cholinesterase inhibitor, were 26 percent less likely to die than people who didn’t take vitamin E. … Continue Reading »

Alzheimer’s vaccine clears plaque but has little effect on learning and memory impairment

A promising vaccine being tested for Alzheimer’s disease does what it is designed to do — clear beta-amyloid plaques from the brain — but it does not seem to help restore lost learning and memory abilities, according to a University of California, Irvine study.

The findings suggest that treating the predominant pathology of Alzheimer’s disease — beta-amyloid plaques — by itself may have only limited clinical benefit if started after there is significant plaque growth. However, a combination of vaccination with therapies that also target related neuron damage and cognitive decline may provide the best treatment opportunity for people with this neurodegenerative disease. Study results appear in the April 2 issue of the Journal of Neuroscience. … Continue Reading »

A coffee with your doughnut could protect against Alzheimer’s disease

A daily dose of caffeine blocks the disruptive effects of high cholesterol that scientists have linked to Alzheimer’s disease. A study in the open access publication, Journal of Neuroinflammation revealed that caffeine equivalent to just one cup of coffee a day could protect the blood-brain barrier (BBB) from damage that occurred with a high-fat diet.

The BBB protects the central nervous system from the rest of the body’s circulation, providing the brain with its own regulated microenvironment. Previous studies have shown that high levels of cholesterol break down the BBB which can then no longer protect the central nervous system from the damage caused by blood borne contamination. BBB leakage occurs in a variety of neurological disorders such as Alzheimer’s disease. … Continue Reading »

No benefit found from continuing neuroleptic drugs in Alzheimer’s patients

Results of a randomised trial published in PLoS Medicine show no benefit in cognitive or neuropsychiatric outcomes from continuing neuroleptic drugs in patients with Alzheimer’s disease.

The researchers, led by Clive Ballard from King’s College hospital, London, recruited 165 patients from across the UK who were already being treated with neuroleptic drugs. They randomised half of the patients to continue treatment and half to discontinue treatment. At 6 and 12 months the patients that remained in each group were assessed for their cognitive status and neuropsychiatric symptoms. The researchers found that there were no differences between the two groups in terms of cognitive decline. They also found no overall differences between the two groups in the change in the number of neuropsychiatric symptoms. Patients with severe neuropsychiatric problems at the outset of the trial may have had some benefit from continued neuroleptic therapy, but this difference was not statistically significant. … Continue Reading »