Where Alzheimer's starts and how it spreads

A new study involving 96 older adults initially free of dementia at the time of enrollment, of whom 12 subsequently developed mild Alzheimer’s, has clarified three fundamental issues about Alzheimer's: where it starts, why it starts there, and how it spreads.

Specifically, it begins in the lateral entorhinal cortex (LEC), a gateway to the hippocampus. Over time, Alzheimer's spreads from the LEC directly to other areas of the cerebral cortex, in particular the parietal cortex. It’s thought that it spreads by compromising the function of neurons in the LEC, which then compromises the integrity of neurons in adjoining areas.

Mouse models comparing the effects of elevated levels of tau in the LEC with elevated levels of APP, and with elevated levels of both, found that LEC dysfunction occurred only in the mice with high levels of both tau and APP. The LEC normally accumulates tau, making it more vulnerable to the accumulation of APP.

http://www.eurekalert.org/pub_releases/2013-12/cumc-ssw121713.php

[3582] Khan, U. A., Liu L., Provenzano F. A., Berman D. E., Profaci C. P., Sloan R., et al.
(2014).  Molecular drivers and cortical spread of lateral entorhinal cortex dysfunction in preclinical Alzheimer's disease.
Nature Neuroscience. 17(2), 304 - 311.

Related News

A study involving 74 older adults (70+), of whom 3 had mild dementia, 33 were cognitively normal and 38 had mild cognitive impairment, has found that high levels of "good" cholesterol and low levels of "bad" cholesterol correlated with lower levels of the amyloid-beta plaques in the brain (a hal

Data from 11 different cohort studies, involving more than 600,000 people from around the world, has found that:

Data from AREDS2, involving 4,203 older adults with age-related macular degeneration, has found that daily dietary supplements of either omega-3 polyunsaturated fatty acids (also found in fish) or lutein and zeaxanthin (nutrients found in green leafy vegetables) were not associated with reduced

A small trial involving seven older adults with insomnia has found that when they consumed 8 ounces of tart cherry juice twice daily for two weeks, they were able to sleep more than an hour longer each night (averaging 84 minutes) compared to when they took the placebo, and their sleep tended to

A study in which 136 older couples (average age 63) filled out questionnaires measuring their overall marriage quality and their perceived support from their spouse, has found that calcification in the coronary arteries was highest when both partners in the relationship viewed each other as offe

Previous research has indicated that about a quarter of older adults who become mildly depressed will go on to become seriously depressed within a year or two.

Two studies help explain why kidney disease increases the risk of cardiovascular diseases such as high blood pressure and vascular calcification. The mediator seems to be a hormone called FGF23, which is sensitive to the level of phosphates in the body.

A study in which 157 healthy adult volunteers were asked to regulate their emotional reactions to unpleasant pictures, has found that those who showed greater brain activation when regulating their negative emotions also had higher blood levels of interleukin-6 (a marker for inflammation) and in

A finding that free radicals promote longevity in the roundworm challenges the theory that free radicals (oxidants) are damaging and cause aging.

A study involving 614 patients with type 2 diabetes (mean age 62) has found that longer duration of diabetes was associated with more brain volume loss, particularly in the gray matter.

Pages

Subscribe to Latest newsSubscribe to Latest newsSubscribe to Latest health newsSubscribe to Latest news
Error | About memory

Error

The website encountered an unexpected error. Please try again later.