Tag Archive for: Alzheimer’s Disease

loss of motivation and Alzheimers disease progression - افسردگی مقدم بر آلزایمر

Researchers from Indiana University School of Medicine are studying why neuropsychiatric symptoms, such as apathy and irritability, appear in most Alzheimer’s disease patients before the onset of memory loss.

The study, led by Yao-Ying Ma, MD, PhD, assistant professor of pharmacology and toxicology, was recently featured in the publication Molecular Psychiatry.

The investigation focused on the nucleus accumbens, a critical brain region processing motivation. Located in the ventral striatum, this region is not studied much among Alzheimer’s disease researchers, Ma said; it’s mainly researched to understand motivational and emotional processes. Previous studies, Ma said, have shown that the volume of nucleus accumbens, like the cortical and hippocampal regions in the brain, is reduced in adults with Alzheimer’s disease.

Ma, who is relatively new to the field of Alzheimer’s disease research, has a background in drug addiction studies and synaptic communication—the process by which neurons talk to each other in the brain. Some of the neuropsychiatric symptoms among people who suffer from substance abuse—apathy, mood swings, anxiety—are also found in Alzheimer’s disease patients.

The investigation focused on the nucleus accumbens, a critical brain region processing motivation. Located in the ventral striatum, this region is not studied much among Alzheimer’s disease researchers, Ma said; it’s mainly researched to understand motivational and emotional processes. Previous studies, Ma said, have shown that the volume of nucleus accumbens, like the cortical and hippocampal regions in the brain, is reduced in adults with Alzheimer’s disease.

Ma, who is relatively new to the field of Alzheimer’s disease research, has a background in drug addiction studies and synaptic communication—the process by which neurons talk to each other in the brain. Some of the neuropsychiatric symptoms among people who suffer from substance abuse—apathy, mood swings, anxiety—are also found in Alzheimer’s disease patients.

These neuropsychiatric symptoms, however, tend to occur earlier than memory loss, but no effective treatments are available, Ma said. She emphasized that there is an urgent need to understand why those symptoms exist and how they correlate with cognitive deficits. Ma said this study identified synaptic calcium permeable receptors (CP-AMPARs) in the nucleus accumbens in an Alzheimer’s disease model. The receptor, which is normally absent in that part of the brain, gives permission for calcium to enter the neurons. This leads to an overload of calcium, which leads to a breakdown of its synaptic structure. In turn, calcium accumulation triggers a cascade of intracellular changes that can be lethal to the neuron by amplifying calcium overload via a positive feedback mechanism.

Release date: 25 April 2022
Source: Indiana University School of Medicine

PHYSICAL FITNESS LINKED TO LOWER RISK OF ALZHEIMERS DISEASE - آمادگی جسمانی و کاهش خطر ابتلا به آلزایمر

“One exciting finding of this study is that as people’s fitness improved, their risk of Alzheimer’s disease decreased—it was not an all-or-nothing proposition,” said study author Edward Zamrini, MD, of the Washington VA Medical Center in Washington, D.C., and a member of the American Academy of Neurology. “So people can work toward making incremental changes and improvements in their physical fitness and hopefully that will be associated with a related decrease in their risk of Alzheimer’s years later.”

The study involved 649,605 military veterans in the Veterans Health Administration database with an average age of 61 who were followed for an average of nine years. They did not have Alzheimer’s disease at the start of the study.

Researchers determined participants’ cardiorespiratory fitness. Cardiorespiratory fitness is a measure of how well your body transports oxygen to your muscles, and how well your muscles are able to absorb oxygen during exercise.

The participants were divided into five groups, from least fit to most fit. Fitness levels were determined by how well participants did on a treadmill test. This test measures exercise capacity, the highest amount of physical exertion a person can sustain. For people who are middle-aged and older, the highest level of fitness can be achieved by walking briskly most days of the week, for two and a half hours or more per week.

The group with the lowest level of fitness developed Alzheimer’s at a rate of 9.5 cases per 1,000 person-years, compared to 6.4 cases per 1,000 person-years for the most fit group. Person-years take into account the number of people in a study as well as the amount of time spent in the study. The case rate decreased as the level of fitness increased, with a rate of 8.5 for the second least fit group, 7.4 for the middle group and 7.2 for the second most fit group.

When researchers adjusted for other factors that could affect risk of Alzheimer’s disease, they found that the people in the most fit group were 33% less likely to develop Alzheimer’s disease than those in the least fit group. The second most fit group was 26% less likely to develop the disease, while the middle group was 20% less likely and those in the second least fit group were 13% less likely to develop the disease than those in the least fit group.

Release date: 27 February 2022
Source: American Academy of Neurology

Ultrasound Stimulation as an Effective Therapy for Alzheimers Disease - امواج فراصوت درمان جدید آلزایمر

Synchronizing one’s brainwaves to ultrasound pulses could reduce the accumulation of abnormal proteins characteristic of the onset of Alzheimer’s diseaseAlzheimer’s disease affects over 50 million people worldwide and is presently incurable. A viable treatment strategy involves reducing abnormal protein accumulation in the brain with gamma waves. However, studies validating its therapeutic effects using non-focused ultrasound with gamma entrainment are lacking. Now, scientists from the Gwangju Institute of Science and Technology demonstrate reduced protein accumulation in the brain by synchronizing brain waves to external ultrasound pulses at gamma frequency, opening doors to a non-invasive therapy.With the increase in average life expectancy in many parts of the world, certain age-related diseases have become more common. Alzheimer’s disease (AD), unfortunately, is one of them, being extremely prevalent within aging societies in Japan, Korea, and various European countries. Currently there is no cure or an effective strategy to slow down the progression of AD. As a result, it causes much suffering to patients, families, and caregivers as well as a massive economic burden. Fortunately, a recent study by a team of scientists at the Gwangju Institute of Science and Technology (GIST) in Korea has just demonstrated that there might be a way to combat AD by using“ultrasound-based gamma entrainment,” a technique that involves syncing up a person’s (or an animal’s) brain waves above 30 Hz (called “gamma waves”) with an external oscillation of a given frequency. The process happens naturally by exposing a subject to a repetitive stimulus, such as sound, light, or mechanical vibrations.Previous studies on mice have shown that gamma entrainment could fight off the formation of β-amyloid plaques and tau protein accumulations—a standard hallmark of the onset of AD. In this recent paper, which was published in Translational Neurodegeneration, the GIST team demonstrated that it is possible to realize gamma entrainment by applying ultrasound pulses at 40 Hz, i.e., in the gamma frequency band, into the brain of an AD-model mice.

Release date: 20 January 2022
Source: GIST (Gwangju Institute of Science and Technology)

Stopping dementia at the nose with combination of rifampicin and resveratrol - امکان کنترل بیماری آلزایمر از راه بینی

Via drug repositioning, Osaka City University creates combination of rifampicin and resveratrol and have shown in mouse models that the nasal administration improves cognitive function without the negative liver side effects of rifampicin alone.

Researchers from Osaka City University have shown in mice models of Alzheimer’s disease, frontotemporal dementia, and dementia with Lewy bodies, that the intranasal administration of rifampicin and resveratrol in combination is safer and improves cognitive function more than rifampicin alone. The research results are expected to lead to the development of safe and effective nasal spray for the prevention of dementia.

 

The results of this study were published online in the Swiss scientific journal Frontiers in Neuroscience.

Release date: 28 December 2021
Source: Osaka City University

Supermeres may carry clues to cancer Alzheimer disease and COVID 19 -سوپرمر کلیددار ابتلا به سرطان آلزایمر و حتی کرونا

Researchers at Vanderbilt University Medical Center have discovered a nanoparticle released from cells, called a “supermere,” which contains enzymes, proteins and RNA associated with multiple cancers, cardiovascular disease, Alzheimer’s disease and even COVID-19.

The discovery, reported Dec. 9 in Nature Cell Biology, is a significant advance in understanding the role extracellular vesicles and nanoparticles play in shuttling important chemical “messages” between cells, both in health and disease.

For one thing, supermeres carry most of the extracellular RNA released by cells and which is found in the bloodstream. Among other functional properties, cancer-derived supermeres can “transfer” drug resistance to tumor cells, perhaps via the RNA cargo they deliver, the researchers reported.

Supermeres are important carriers of TGFBI, a protein that in established tumors promotes tumor progression. TGFBI thus may be a useful marker in liquid biopsies for patients with colorectal cancer, the researchers noted.

They also carry ACE2, a cell-surface receptor that plays a role in cardiovascular disease and is the target of the COVID-19 virus. This raises the possibility that ACE2 carried by supermeres could serve as a “decoy” to bind the virus and prevent infection.

Another potentially important cargo is APP, the amyloid-beta precursor protein implicated in the development of Alzheimer’s disease. Supermeres can cross the blood-brain barrier, suggesting that their analysis could improve early diagnosis or possibly even targeted treatment of the disease.

Release date: 10 December 2021
Source: Vanderbilt University Medical Center

Coffee could lower risCoffee could lower risk of Alzheimer disease - کاهش خطر ابتلا به آلزایمر خبری خوش برای دوستداران قهوهk of Alzheimer disease - کاهش خطر ابتلا به آلزایمر خبری خوش برای دوستداران قهوه

Good news for those of us who can’t face the day without their morning flat white: a long-term study has revealed drinking higher amounts of coffee may make you less likely to develop Alzheimer’s disease.

As part of the Australian Imaging, Biomarkers and Lifestyle Study of ageing, researchers from Edith Cowan University (ECU) investigated whether coffee intake affected the rate of cognitive decline of more than 200 Australians over a decade.

Lead investigator Dr Samantha Gardener said results showed an association between coffee and several important markers related to Alzheimer’s disease.

‘Higher Coffee Consumption Is Associated With Slower Cognitive Decline and Less Cerebral Aβ-Amyloid Accumulation Over 126 Months: Data From the Australian Imaging, Biomarkers, and Lifestyle Study’ was published in Frontiers in Aging Neuroscience.

Release date: 23 November 2021
Source: Edith Cowan University

Alzheimers and Covid-19 share a genetic risk factor - کرونا و آلزایمر

An anti-viral gene that impacts the risk of both Alzheimer’s disease and severe Covid-19 has been identified by a UCL-led research team.

The researchers estimate that one genetic variant of the OAS1 gene increases the risk of Alzheimer’s disease by about 3-6% in the population as a whole, while related variants on the same gene increase the likelihood of severe Covid-19 outcomes.

The findings, published in Brain, could open the door for new targets for drug development or tracking disease progression in either disease, and suggest that treatments developed could be used for both conditions. The findings also have potential benefits for other related infectious conditions and dementias.

Release date: 08 October 2021
Source: University College London

Natural compound in basil may protect against Alzheimers disease pathology - سبزی با خاصیت ضد آلزایمر

Fenchol, a natural compound abundant in some plants including basil, can help protect the brain against Alzheimer’s disease pathology, a preclinical study led by University of South Florida Health (USF Health) researchers suggests.

The new study published in the Frontiers in Aging Neuroscience, discovered a sensing mechanism associated with the gut microbiome that explains how fenchol reduces neurotoxicity in the Alzheimer’s brain.

Emerging evidence indicates that short-chain fatty acids (SCFAs)– metabolites produced by beneficial gut bacteria and the primary source of nutrition for cells in your colon — contribute to brain health. The abundance of SCFAs is often reduced in older patients with mild cognitive impairment and Alzheimer’s disease, the most common form of dementia. However, how this decline in SCFAs contributes to Alzheimer’s disease progression remains largely unknown.

Gut-derived SCFAs that travel through the blood to the brain can bind to and activate free fatty acid receptor 2 (FFAR2), a cell signaling molecule expressed on brain cells called neurons.

“Our study is the first to discover that stimulation of the FFAR2 sensing mechanism by these microbial metabolites (SCFAs) can be beneficial in protecting brain cells against toxic accumulation of the amyloid-beta (Aβ) protein associated with Alzheimer’s disease,” said principal investigator Hariom Yadav, PhD, professor of neurosurgery and brain repair at the USF Health Morsani College of Medicine, where he directs the USF Center for Microbiome Research.

Release date: 05 October 2021
Source: University of South Florida

possible link between herpes simplex and neurodegenerative diseases - ارتباط ویروس تب خال با تخریب اعصاب

A new study by researchers at University of Illinois Chicago suggests that when the protein optineurin, or OPTN, is present in cells it restricts the spread of HSV-1, the herpes simplex virus type 1.

In a “first of its kind” study, researchers also found a potential direct connection between neurodegenerative diseases, such as Alzheimer’s disease, amyotrophic lateral sclerosis (ALS), glaucoma, and the herpesvirus, said Dr. Deepak Shukla, the Marion H. Schenk Esq. Professor in Ophthalmology for Research of the Aging Eye, and vice chair for research at UIC.

The research paper, “OPTN is a host intrinsic restriction factor against neuroinvasive HSV-1 infection,” led by Shukla, was published recently in the journal Nature Communications.

Researchers sought to discover why HSV-1 can become fatal for individuals who are immunocompromised but not for healthy individuals. Herpesviruses naturally infect the central nervous system and can result in degenerative brain and eye disorders, as well as encephalitis. However, in most individuals, the virus is suppressed during a primary infection before it can significantly damage the central nervous system.

The new research suggests why HSV-1 is suppressed: OPTN, a conserved autophagy receptor, selectively targets HSV-1 proteins to degradation by autophagy, explained Tejabhiram Yadavalli, a co-author of the study and visiting scholar at UIC’s department of ophthalmology and visual science.

Release date: 13 September 2021
Source: University of Illinois at Chicago

COVID19 Linked to Alzheimers Disease like Cognitive Impairment - اختلالات شناختی کووید۱۹

A new Cleveland Clinic-led study has identified mechanisms by which COVID-19 can lead to Alzheimer’s disease-like dementia. The findings, published in Alzheimer’s Research & Therapy, indicate an overlap between COVID-19 and brain changes common in Alzheimer’s, and may help inform risk management and therapeutic strategies for COVID-19-associated cognitive impairment.

Reports of neurological complications in COVID-19 patients and “long-hauler” patients whose symptoms persist after the infection clears are becoming more common, suggesting that SARS-CoV-2 (the virus that causes COVID-19) may have lasting effects on brain function. However, it is not yet well understood how the virus leads to neurological issues.

Release date: 10 Jun 2021
Source: Cleveland Clinic