August 30, 2017

Health Roundup: Alzheimer's edition

Huge increase in Alzheimer's-related deaths in the first few months of 2017, CDC report reveals  In the first quarter of 2017 there were 1.13 as many deaths from the disease as in the first quarter of 2016.

'Ground zero' of Alzheimer's 

Researchers from the UNC Medical School may have discovered how brain cells go bad in Alzheimer's patients. They found bead-like structures that form and indicate the disease are caused by two proteins -MMP-9 and HDAC6.

Alzheimer's disease causes abnormal deposits of amyloid beta protein and tau protein in the brain, as well as swarms of activated immune cells. The team of researchers used different experiments to look at how the proteins and activated immune cells attack the brain and cause Alzheimer's-related symptoms. They also found that one medicine currently in development that blocks a specific protein - HDAC6, which originates from within neurons - show progress in preventing the damage that causes those symptoms.  The drug, called tubastatin A, is currently undergoing late stage clinical trials at a number of hospitals around the United States. 

Led by Dr Todd Cohen, assistant professor of neurology, UNC scientists used human cell cultures to show how amyloid beta can trigger a dramatic inflammatory response in immune cells and how that interaction damages neurons. The team then showed how that kind of neuron damage leads to the formation of bead-like structures filled with abnormal tau protein.  Similar bead-like structures are known to form in the brain cells of people with Alzheimer's disease.

The UNC researchers also identified two proteins - MMP-9 and HDAC6 - that help promote this harmful, amyloid-to-inflammation-to-tau cascade. These proteins and others associated with them could become drug targets to treat or prevent Alzheimer's.'It's exciting that we were able to observe tau - the major Alzheimer's protein - inside these beaded structures,' said Dr Cohen, who is also a member of the UNC Neuroscience Center. 'We think that preventing these structures from forming would leave people with healthier neurons that are more resistant to Alzheimer's.'

Higher risk of Alzheimer's associated with:

1. Bad sleep could raise the risk of dementia by 10%

Deep sleep - also called rapid eye movement sleep - could fight off dementia Scientists believe that the dreaming stage of sleep boosts connections in the brain, helping to protect it against the onset of the disease... The authors of the study said it did not show cause and effect – so it was not possible to confirm whether a lack of REM sleep was causing dementia or whether it was simply an early predictor of the disease.

2. Adults with bad eyesight have higher risk of dementia

A significant link between vision loss and a decline in cognitive function has been uncovered by researchers at Stanford University.  The team of researchers analyzed two sets of data covering about 33,000 people to connect the dots between poor sight and dementia risks. The link wasn't weakened even after scientists adjusted for demographics, health and other factors....The researchers said their study was observational and could not establish exactly why vision loss is linked to cognitive decline. However, both symptoms are known to occur as people become older - suggesting they may both go hand-in-hand.

3. Lower serotonin levels are linked to dementia according to brain scan study.

Results suggest serotonin loss may be a key player in cognitive decline, not just a side-effect of Alzheimer's disease.  In a study looking at brain scans of people with mild loss of thought and memory ability, Johns Hopkins researchers report evidence of lower levels of the serotonin transporter -- a natural brain chemical that regulates mood, sleep and appetite....."Now that we have more evidence that serotonin is a chemical that appears affected early in cognitive decline, we suspect that increasing serotonin function in the brain could prevent memory loss from getting worse and slow disease progression," says Gwenn Smith, Ph.D., director of geriatric psychiatry and neuropsychiatry at Johns Hopkins University School of Medicine.

4. Spinach may cause Alzheimer's disease in at-risk people, research suggests.

The salad leaf's iron-rich content may damage the brain similar to how the compound causes metal to rust, according to new research. People with high levels of iron alongside the protein amyloid, which has previously been associated with Alzheimer's, are more likely to experience rapid cognitive decline, a study found while those with high amyloid but low iron levels are less at-risk of the disease.

Removing such 'rust' from the brain could prevent or delay the degenerative condition, the researchers add. Although iron is important for energy, it can cause cellular stress and their subsequent death. The researchers plan to conduct a five-year trial investigating whether an anti-iron drug could treat Alzheimer's.  Do not cut back on dietary iron. The researchers do not recommend people cut back on their dietary iron intake to reduce their Alzheimer's risk. This is because the amount of the iron in the brain appears unrelated to levels in the blood or a person's food intake.

5. Women face a greater risk of developing dementia during a crucial 10-year span, between 65 and 75

The team of researchers from the Keck School of Medicine of the University of Southern California, analyzed 27 independent studies, featuring data on a total of 57,979 individuals diagnosed with Alzheimer's from North America and Europe. They found women are more at risk during the crucial 10-year span from 65-75. But contrary to past studies, there is no difference between the sexes from 55-85...Study co-author Dr Judy Pa,  said: 'The bottom line is women are not little men. A lot more research needs to target women because gender-specific variations can be so subtle that scientists often miss them. Most research today is ignoring a big part of the equation.'

Draper develops technique to predict cognitive decline in Alzheimer's

When patients are diagnosed with Alzheimer’s, it is often difficult to know how rapidly the disease will progress. But researchers at Cambridge-based Draper say that they can help researchers answer that very question, using artificial intelligence to study MRI data from Alzheimer’s patients....“This is one step forward to making better use of the biological data we have in order to obtain more informed insights into the mechanisms of Alzheimer’s disease.” ....The technique is intended for researchers more than clinicians, and likely won’t be available to patients anytime soon

New eye test could spot Alzheimer's disease 20 YEARS before symptoms emerge  Retinal scan

Researchers at Cedars-Sinai developed an eye test as a non-invasive method. Comparing their results to brain scans, the eye test was just as successful at spotting those with twice the amount of plaque build-up in their brains....

For the study, the researchers conducted a clinical trial on 16 AD patients who drank a solution that includes curcumin, a natural component of the spice turmeric. The curcumin causes amyloid plaque in the retina to "light up" and be detected by the scan. The patients were then compared to a group of younger, cognitively healthy individuals.

The researchers found their results were as accurate as those found via standard invasive methods.  Until about a decade ago, the only way to officially diagnose someone with Alzheimer's disease was to analyze their brain posthumously. In recent years, physicians have been able to use positron emission tomography (PET) scans of the brains of living people, to identify markers of the disease. However, the technology is expensive, and the test is invasive, since the patient needs to be injected with radioactive tracers. Experts say the finding is one of the biggest breakthroughs in Alzheimer's research to date, offering the first sign of a cost-effective and non-invasive test.
'This study adds to existing evidence pointing to the possibility of detecting this feature of Alzheimer's in the retina, by using equipment that already helps ophthalmologists diagnose problems like glaucoma or macular degeneration.

Blocking enzyme HDAC2, which is linked to Alzheimer's may reverse memory loss

In the brains of Alzheimer's patients, many of the genes required to form new memories are shut down by a genetic blockade, contributing to the cognitive decline seen in those patients.  MIT researchers have now shown that they can reverse that memory loss in mice by interfering with the enzyme that forms the blockade. The enzyme, known as HDAC2, turns genes off by condensing them so tightly that they can't be expressed.

Scientists believe they have found a drug that could treat childhood Alzheimer's

The disease is called Niemann-Pick type C (NPC) and causes enlarged organs, dementia and difficulty speaking. The study shows that a sugar molecule called cyclodextrin slows progression and can return some brain function in NPC patients.
Posted by Jill Fallon at August 30, 2017 7:48 PM | Permalink