Researchers have identified nine genes that might make people more likely to develop Alzheimer’s disease. They confirmed earlier reports that a variation in the vitamin D3 receptor gene, on chromosome 12, might also increase risk for Alzheimer’s. Low levels of vitamin D have been found in people with Alzheimer’s and other dementias, leading researchers to suspect a link.In their study, the researchers compared 550,000 genetic variations in about 500 people with Alzheimer’s and 500 people without the disease
Their findings are published in the January issue of The American Journal of Human Genetics,
New study supports statin’s anti-dementia effects
NEW YORK (Reuters Health January 8, 2009) – In the largest cohort study to date, treatment with a cholesterol-lowering statin drug was found to reduce new cases of Alzheimer’s disease, regardless of the specific type of statin used or a person’s genetic risk for the disease. Numerous studies have looked at the relationship between statin use and the development of Alzheimer’s disease, with conflicting results. One explanation for the inconsistencies is that only the fat soluble or “lipophilic” statins, which could get into the brain more easily than water soluble or “hydrophilic” statins, were included in the studies. Dr. M. M. B. Breteler and colleagues at the Erasmus Medical Centre in Rotterdam, the Netherlands, analyzed data from the prospective, population-based Rotterdam Study. The analysis included 6992 subjects, 55 years old or older, who were free of dementia when examined between 1990 and 1993.
During follow-up until 2005 (an average of 9.2 years), 582 subjects were diagnosed with Alzheimer’s. After controlling for social, demographic and clinical factors that might raise a person’s risk of getting the disease, statin users had a significant 43 percent reduced risk of Alzheimer’s disease compared with those who never used statins. The protective effect was similar for fat soluble and water soluble statins.
The protective effect of statin use against Alzheimer’s disease was also similar for persons with and without the major gene mutation associated with Alzheimer,s disease ( the apolipoprotein E-epsilon-4 allele)
Journal of Neurology, Neurosurgery and Psychiatry, January 2009.
SRF (serum response factor) and myocardin — lessen blood flow in the brain and reduce the rate at which the brain is able to remove amyloid beta, the protein that accumulates in damaging quantities in the brains of Alzheimer’s patients. Two processes are believed to play a role in Alzheimer’s: a reduction in blood flow and a buildup of amyloid beta. These two proteins known for their role in the cardiovascular system were major factors in the development of Alzheimer’s disease. The study was published online Dec. 21 in the journal Nature Cell Biology.
- Martin Eastwood