Thursday November 21, 2019

A Landmark Study Links Herpes 6 and 7 with Alzheimer’s Disease

The findings also showed multiple points of overlap between virus-host interactions and genes associated with Alzheimer's risk

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For the study, published in the journal Nature, the team engineered a hydrogel that can swell those lymphatic vessels.
For the study, published in the journal Nature, the team engineered a hydrogel that can swell those lymphatic vessels. (IANS)

Scientists have found up to two times higher level of human herpes virus among people with Alzheimer’s disease, suggesting the potential role of the viruses in the development of the progressive brain disorder.

Herpes virus causes contagious sores, most often around the mouth or on the genitals.

The study found unusually increased level of human herpesvirus named human herpesvirus 6A (HHV-6A) and human herpesvirus 7 (HHV-7 ) in the brains of the people with Alzheimer’s than those without the disorder.

“The hypothesis that viruses play a part in brain disease is not new, but this is the first study to provide strong evidence,” said Richard J. Hodes, Director from the US National Institutes of Health.

“Our work identified specific biological networks that offer new testable hypotheses regarding the role of microbial defense and innate immune function in the pathophysiology of Alzheimer’s,” said Joel Dudley from the Institute for Next Generation Healthcare at the Icahn School of Medicine at Mount Sinai.

alzheimers
Patient of Alzheimer’s. Pixabay

The findings also showed multiple points of overlap between virus-host interactions and genes associated with Alzheimer’s risk. Multiple viruses impact the biology of Alzheimer’s disease across domains such as DNA, RNA and proteins.

“If it becomes evident that specific viral species directly contribute to an individual’s risk of developing Alzheimer’s or their rate of progression once diagnosed, then this would offer a new conceptual framework for understanding the emergence and evolution of Alzheimer’s at individual, as well as population, levels,” Dudley explained.

In the study, published in the journal Neuron, the team initially performed RNA sequencing on four brain regions in more than 600 samples of postmortem tissue from people with and without Alzheimer’s to quantify which genes were present in the brain, and whether any were associated with the onset and progression of Alzheimer’s.

Also Read: Parkinson’s Identified Gene to Combat Alzheimer’s

Using different computational approaches, the team uncovered a complex network of unexpected associations, linking specific viruses with different aspects of Alzheimer’s biology.

They examined the influence of each virus on specific genes and proteins in brain cells, and identified associations between specific viruses and amyloid plaques, neurofibrillary tangles, and clinical dementia severity.

Further, they incorporated 800, RNA sequencing samples and observed a persistent increase of HHV-6A and HHV-7 in samples from individuals with Alzheimer’s. (IANS)

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Exposure to Air Pollution May Trigger Alzheimer’s in Aged Women, Reveals Research

"Our hope is that by better understanding the underlying brain changes caused by air pollution, researchers will be able to develop interventions to help people with or at risk for cognitive decline," Petkus added

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A lady suffering from Alzheimer's. Flickr

Women in their 70s and 80s who were exposed to higher levels of air pollution experienced greater declines in memory and more Alzheimer’s-like brain atrophy than their counterparts who breathed cleaner air, new research has revealed.

“This is the first study to really show, in a statistical model, that air pollution was associated with changes in people’s brains and that those changes were then connected with declines in-memory performance,” said study researcher Andrew Petkus, the Assistant Professor University of South California in the US.

Previous research has suggested that fine particle pollution exposure increases the risk for Alzheimer’s disease and related dementias.

What scientists haven’t known is whether PM2.5 alters brain structure and accelerates memory decline.

For the study, published in the journal Brain, researchers used data from 998 women, aged 73 to 87, who had up to two brain scans five years apart as part of the landmark Women’s Health Initiative launched in 1993 by the US National Institutes of Health and enrolled more than 160,000 women to address questions about heart disease, cancer, and osteoporosis.

"The question for us now is not how to eliminate cholesterol from the brain, but about how to control cholesterol's role in Alzheimer's disease through the regulation of its interaction with amyloid-beta," Vendruscolo said.
In Alzheimer’s disease, patients start losing memory. Pixabay

Those brain scans were scored on the basis of their similarity to Alzheimer’s disease patterns by a machine learning tool that had been “trained” via brain scans of people with Alzheimer’s disease.

The researchers also gathered information about where the 998 women lived, as well as environmental data from those locations to estimate their exposure to fine particle pollution.

When all that information was combined, researchers could see the association between higher pollution exposure, brain changes and memory problems — even after adjusting to taking into account differences in income, education, race, geographic region, cigarette smoking, and other factors.

Also Read: Facebook, Google Performing an Assault on the Right to Privacy

“This study provides another piece of the Alzheimer’s disease puzzle by identifying some of the brain changes linking air pollution and memory decline. Each research study gets us one step closer to solving the Alzheimer’s disease epidemic,” Petkus said.

“Our hope is that by better understanding the underlying brain changes caused by air pollution, researchers will be able to develop interventions to help people with or at risk for cognitive decline,” Petkus added. (IANS)