Diabetes drug holds promise of being developed into new treatment for Alzheimer's

A drug developed for diabetes could be used to treat Alzheimer's after scientists found it "significantly reversed memory loss" in mice through a triple method of action.

The research, published in Brain Research, could bring substantial improvements in the treatment of Alzheimer's disease through the use of a drug originally created to treat type 2 diabetes.

Lead researcher Professor Christian Holscher of Lancaster University in the UK said the novel treatment "holds clear promise of being developed into a new treatment for chronic neurodegenerative disorders such as Alzheimer's disease."

Alzheimer's disease is the most common cause of dementia and the numbers are expected to rise to two million people in the UK by 2051 according to Alzheimer's Society, who part- funded the research.

Dr Doug Brown, Director of Research and Development at Alzheimer's Society, said: ""With no new treatments in nearly 15 years, we need to find new ways of tackling Alzheimer's. It's imperative that we explore whether drugs developed to treat other conditions can benefit people with Alzheimer's and other forms of dementia. This approach to research could make it much quicker to get promising new drugs to the people who need them."

Although the benefits of these 'triple agonist' drugs have so far only been found in mice, other studies with existing diabetes drugs such as liraglutide have shown real promise for people with Alzheimer's, so further development of this work is crucial."

This is the first time that a triple receptor drug has been used which acts in multiple ways to protect the brain from degeneration. It combines GLP-1, GIP and Glucagon which are all growth factors. Problems with growth factor signaling have been shown to be impaired in the brains of Alzheimer's patients.

The study used APP/PS1 mice, which are transgenic mice that express human mutated genes that cause Alzheimer's. Those genes have been found in people who have a form of Alzheimer's that can be inherited. Aged transgenic mice in the advanced stages of neurodegeneration were treated.

In a maze test, learning and memory formation were much improved by the drug which also:-

• enhanced levels of a brain growth factor which protects nerve cell functioning
• reduced the amount of amyloid plaques in the brain linked with Alzheimer's
• reduced both chronic inflammation and oxidative stress
• slowed down the rate of nerve cell loss

Professor Holscher said: "These very promising outcomes demonstrate the efficacy of these novel multiple receptor drugs that originally were developed to treat type 2 diabetes but have shown consistent neuro- protective effects in several studies."

"Clinical studies with an older version of this drug type already showed very promising results in people with Alzheimer's disease or with mood disorders"

"Here we show that a novel triple receptor drug shows promise as a potential treatment for Alzheimer's but further dose-response tests and direct comparisons with other drugs have to be conducted in order to evaluate if this new drugs is superior to previous ones."

Type 2 diabetes is a risk factor for Alzheimer's and has been implicated in the progression of the disease. Impaired insulin has been linked to cerebral degenerative processes in type 2 diabetes and Alzheimer's disease. Insulin desensitisation has also been observed in the Alzheimer's disease brain. The desensitisation could play a role in the development of neurodegenerative disorders as insulin is a growth factor with neuroprotective properties.

Ref : http://www.research.lancs.ac.uk/portal/en/publications/-(ccd64550-72ab-4d4b-9e42-986da99f7b36).html

Diabetes drug holds promise of being developed into new treatment for Alzheimer's

Study first to show pharmacological chaperone therapy prevents Alzheimer's in mice

Like pieces of tape that crumple, stick together, and can be turned into a ball, proteins that begin to lose their shape become sticky and tend to clump together. When this happens, rather than being transported to recycling sites within cells, old or dysfunctional proteins instead become trapped within cellular compartments. Eventually, they accumulate to the point that they gum up cellular machinery, causing major problems.

Fortunately, cells are equipped with molecular machinery that detects defective proteins, sorts them out, and then either removes or stabilizes them, preventing them from accumulating and causing harm. In recent years, scientists have developed small drug molecules, known as pharmacological chaperones, that can help in this process.

Now, scientists at the Lewis Katz School of Medicine at Temple University show that pharmacological chaperones could fill a critical role in Alzheimer's disease therapy. In a new study published online January 21 in the journal Molecular Neurodegeneration, they describe a novel pharmacological chaperone capable of preventing Alzheimer's disease in animals prone to developing the condition.

The study is the first to show that a pharmacological chaperone drug can effectively disrupt the abnormal processes that damage neurons in the brain, fuel memory loss, and ultimately give rise to Alzheimer's disease.

"Our chaperone drug specifically restored levels of a sorting molecule known as VPS35, which helps move proteins out of endosomes, compartments inside cells where proteins are sorted for degradation," explained Domenico Praticò, MD, the Scott Richards North Star Charitable Foundation Chair for Alzheimer's Research, Professor in the Departments of Pharmacology and Microbiology, and Director of the Alzheimer's Center at Temple in the Lewis Katz School of Medicine. Dr. Praticò was a senior investigator on the new study.

The trafficking of proteins from endosomes to the cell membrane or to another cellular compartment known as the Golgi apparatus is fundamental for normal cell function. VPS35 is of particular importance to this trafficking system since it separates out dysfunctional and old proteins and sends them off for recycling.

In previous work, Dr. Praticò and colleagues found that VPS35 actively clears the brain of potentially harmful proteins such as amyloid-beta and tau. However, in Alzheimer's disease, VPS35 levels are reduced. This reduction is associated with the formation of tau tangles inside neurons, as well as the accumulation of amyloid-beta outside neurons. Eventually, these deposits of abnormal proteins interrupt neuron activity and contribute to neurodegenerative disorders, including Alzheimer's disease.

In the new study, the researchers investigated the effects of a pharmacological chaperone on protein sorting in mice engineered to develop Alzheimer's disease as they age. Mice were treated from a young age, before they began to show signs of disease. As the animals grew older, they were tested for effects on memory and learning.

Dr. Praticò's team found that, compared to untreated mice destined for Alzheimer's disease, the treated animals had much better memory and behaved just like normal, or wild-type, mice. When the researchers examined neurons from treated mice, they observed significant decreases in tau tangles, as well as decreases in amyloid-beta plaques—another type of protein aggregate that contributes to Alzheimer's disease. The researchers further noticed that VPS35 levels were restored and the junctions where neurons come together to exchange information, known as synapses, were fully functional following the pharmacological chaperone therapy.

"Relative to other therapies under development for Alzheimer's disease, pharmacological chaperones are inexpensive, and some of these drugs have already been approved for the treatment of other diseases," Dr. Praticò said. "Additionally, these drugs do not block an enzyme or a receptor but target a cellular mechanism, which means that there is much lower potential for side effects. All these factors add to the appeal of pursuing pharmacological chaperone drugs as novel Alzheimer's treatments."

Before moving to trials in human patients, however, Dr. Praticò plans to next investigate the effects of pharmacological chaperone therapy in older mice. "Because our most recent investigation was a preventative study, we want to know now whether this therapy could also work as a treatment for patients already diagnosed with Alzheimer's disease," he added.

https://molecularneurodegeneration.biomedcentral.com/articles/10.1186/s13024-019-0350-4

https://en.wikipedia.org/wiki/Pharmacological_chaperone

https://en.wikipedia.org/wiki/VPS35

Study first to show pharmacological chaperone therapy prevents Alzheimer's in mice

Trends in drug discovery for Alzheimer's disease.....

In continuation of my update on Alzheimer' disease and drug discovery...

We  know that Alzheimer’s disease(named after Dr. Alois Alzheimer. In 1906) is an irreversible, progressive brain disease that slowly destroys memory and thinking skills, and eventually even the ability to carry out the simplest tasks. In most people with Alzheimer’s, symptoms first appear after age 60. 

Alzheimer’s disease is the most common cause of dementia(loss of cognitive functioning—thinking, remembering, and reasoning to such an extent that it interferes with a person’s daily life and activities) among older people. Dementia is the  Estimates vary, but experts suggest that as many as 5.1 million Americans may have Alzheimer’s and Alzheimer's is predicted to affect 1 in 85 people globally by 2050. 

Future drugs for Alzheimer’s disease : 

Thirty years ago, we knew very little about Alzheimer’s disease (with four medications approved so for...). Since then, scientists have made many important advances. Research supported by NIA and other organizations has expanded knowledge of brain function in healthy older people, identified ways we might lessen normal age-related declines in mental function, and deepened our understanding of the disease. Many scientists and physicians are now working together to untangle the genetic, biological, and environmental factors that, over many years, ultimately result in Alzheimer’s. This effort is bringing us closer to the day when we will be able to manage successfully or even prevent this devastating disease.

A recent research survey claim that, symptomatic market will remain active in this disease. New symptomatic entrants to the market will include Aricept patch and the first-in-class 5-HT6 receptor antagonist SB-742457.  Datamonitor forecasts that the current late-stage pipeline will yield three blockbusters, but this is by no means guaranteed considering the high risk of failure in Phase III Alzheimer’s disease trials. Of the pipeline drugs, Datamonitor believes that bapineuzumab(an antibody to the beta-amyloid (Aβ) plaques) and solanezumab (a humanized antibody that binds to soluble ß-amyloid and thereby may draw the peptide away from the brain through the blood and this could reduce the formation of amyloid plaque)have the most commercial and clinical potential. Research survey conclude that value of the Alzheimer’s disease market across the seven major markets was $4.7bn in 2009 and is forecast to reach $11.9bn by 2019. More....

 

FDA-approved blood pressure drug reduces cell damage linked to Alzheimer's disease

In laboratory neuronal cultures, an FDA-approved drug used to treat high blood pressure reduced cell damage often linked to Alzheimer's disease, say researchers at Georgetown University Medical Center (GUMC) and the National Institutes of Health.

They say their work, published online Jan. 28 in the journal Alzheimer's Research and Therapy, provides information supporting the potential effect of the drug candesartan -- as well as other Angiotensin receptor blockers (ARBs) for the early treatment of Alzheimer's disease.

"Our findings make sense in many ways," says the study's senior author Juan M. Saavedra, MD, from GUMC's Department of Pharmacology and Physiology. "Hypertension reduces blood flow throughout the body and brain and is a risk factor of Alzheimer's disease. Previous epidemiological studies found that Alzheimer's progression is delayed in hypertensive patients treated with ARBs."

Using neuronal cultures, the researchers explored the action of candesartan on the neurotoxic effects of exposure to excessive glutamate, a demonstrated injury factor in the early stages of Alzheimer's disease.

The scientists found that candesartan prevented glutamate-induced neuronal death. They conducted in-depth gene analyses of the laboratory results, demonstrating that candesartan prevented neuronal inflammation and many other pathological processes, including alterations in amyloid metabolism, a hallmark of Alzheimer's disease.

The study's first author, Abdel G. Elkahloun, PhD, from the Comparative Genomics and Cancer Genetics Branch of the National Human Genome Research Institute, then compared gene expression in the neuronal cultures with published gene databases of autopsy samples from Alzheimer's disease patients. "The correlations were impressive -- the expression of 471 genes that were altered by excess glutamate in our cultures were also altered in brain autopsy samples from patients who suffered from Alzheimer's disease. Candesartan normalized expression of these genes in our cultures," Elkahloun says.

"We hypothesize that candesartan, or other members of the ARB group, may not only slow progression of Alzheimer's but also prevent or delay its development," Saavedra says.

FDA-approved blood pressure drug reduces cell damage linked to Alzheimer's disease: In laboratory neuronal cultures, an FDA-approved drug used to treat high blood pressure reduced cell damage often linked to Alzheimer's disease, say researchers at Georgetown University Medical Center and the National Institutes of Health.

Study: Antioxidant flavonol linked to lower risk of Alzheimer's dementia

In continuation of my update on kaempferol, myricetin and  quercetin

 

                                                                 kaempferol

                                                                       

                                                                      myricetin

                                                 

                                                                          Quercetin

        

People who eat or drink more foods with the antioxidant flavonol, which is found in nearly all fruits and vegetables as well as tea, may be less likely to develop Alzheimer's dementia years later, according to a study published in the January 29, 2020, online issue of Neurology, the medical journal of the American Academy of Neurology.

"More research is needed to confirm these results, but these are promising findings," said study author Thomas M. Holland, MD, of Rush University in Chicago. "Eating more fruits and vegetables and drinking more tea could be a fairly inexpensive and easy way for people to help stave off Alzheimer's dementia. With the elderly population increasing worldwide, any decrease in the number of people with this devastating disease, or even delaying it for a few years, could have an enormous benefit on public health."

Flavonols are a type of flavonoid, a group of phytochemicals found in plant pigments known for its beneficial effects on health.

The study involved 921 people with an average age of 81 who did not have Alzheimer's dementia. The people filled out a questionnaire each year on how often they ate certain foods. They were also asked about other factors, such as their level of education, how much time they spent doing physical activities and how much time they spent doing mentally engaging activities such as reading and playing games.

The people were tested yearly to see if they had developed Alzheimer's dementia. They were followed for an average of six years. The researchers used various tests to determine that 220 people developed Alzheimer's dementia during the study.

The people were divided into five groups based on how much flavonol they had in their diet. The average amount of flavonol intake in US adults is about 16 to 20 milligrams per day. In the study, the lowest group had intake of about 5.3 mg per day and the highest group consumed an average of 15.3 mg per day.

The study found that people in the highest group were 48 percent less likely to later develop Alzheimer's dementia than the people in the lowest group after adjusting for genetic predisposition and demographic and lifestyle factors. Of the 186 people in the highest group, 28 people, or 15 percent, developed Alzheimer's dementia, compared to 54 people, or 30 percent, of the 182 people in the lowest group.

The results were the same after researchers adjusted for other factors that could affect the risk of Alzheimer's dementia, such as, diabetes, previous heart attack, stroke and high blood pressure.

The study also broke the flavonols down into four types: isorhamnetin, kaempferol, myricetin and quercetin. The top food contributors for each category were: pears, olive oil, wine and tomato sauce for isorhamnetin; kale, beans, tea, spinach and broccoli for kaempferol; tea, wine, kale, oranges and tomatoes for myricetin; and tomatoes, kale, apples and tea for quercetin.

People who had high intake of isorhamnetin were 38 percent less likely to develop Alzheimer's. Those with high intake of kaempferol were 51 percent less likely to develop dementia. And those with high intake of myricetin were also 38 percent less likely to develop dementia. Quercetin was not tied to a lower risk of Alzheimer's dementia.

Holland noted that the study shows an association between dietary flavonols and Alzheimer's risk but does not prove that flavonols directly cause a reduction in disease risk.

Other limitations of the study are that the food frequency questionnaire, although valid, was self-reported, so people may not accurately remember what they eat, and the majority of participants were white people, so the results may not reflect the general population.

https://en.wikipedia.org/wiki/Myricetin

https://en.wikipedia.org/wiki/Quercetin

https://medicalxpress.com/news/2019-07-high-hemoglobin-linked-dementia.html

New compound prevents amyloid formation to fight Alzheimer’s disease

It is known that Alzheimer’s disease is caused by the formation of amyloid plaques and tau tangles in the brain. A novel compound shows promise in preventing amyloid formation, fighting Alzheimer’s disease development.

       

Alzheimer’s disease (AD) is the most common form of dementia, affecting about 50 million people worldwide. In the United States, 5.5 million people are living with neurodegenerative diseases, making it the 6th leading cause of death in the country.

AD is caused by the abnormal build-up of proteins, amyloid, and tau, in and around the brain. These proteins form plaques and tangles in brain cells, leading to memory loss and other symptoms. Abnormal proteins form toxic clumps, dubbed as fibrils, inside the brain, affecting brain regions that are vital for brain processes.

In the study published in the journal Chemical Communications by the Royal Society of Chemistry, reveals that the new compound, known as “C1”, can prevent the enzyme gamma-secretase from producing amyloids.

What is the role of C1?

Amyloid fibrils are made of peptide amyloid-beta, produced when certain enzymes make cuts to the amyloid precursor protein, which is found in the brain cell membrane. A type of covalent gamma-secretase inhibitor, the compound works by blocking the active site of the enzyme, hence, preventing the formation of amyloid.

The team of researchers at the Center for Biotechnology and Interdisciplinary Studies (CBIS) at Rensselaer Polytechnic Institute noted that there were samples of gamma-secretase inhibitors in the past, but these failed since they have severe side effects. What happened is, the inhibitors used stopped all the functions of gamma-secretase.

“Our compound binds to the cleavage site of the precursor protein instead of the enzyme itself, which may avoid many problems associated with traditional enzyme inhibitors,” Chunyu Wang, a professor of biological sciences and author of the study, said.

The team started to screen drugs to determine a potential compound that can target the amyloid precursor protein substrate, blocking the gamma-secretase activity that is tied to amyloid production. Using a computer model, they tested millions of compounds in the hopes of finding the one that can show promise in battling Alzheimer’s disease.

Though there were several candidates found, C1 showed high accuracy and effectiveness in cell cultures and test tubes. The patent for the compound is still pending but the researchers hope that the new drug can be studied more to determine its efficacy in people at a high risk of developing Alzheimer’s disease.

Implications of the compound

The discovery of the novel compound can pave the way for the development of new drugs that can prevent and treat Alzheimer’s disease. The new approach targets the disease, based on tis principal pathology.

Currently, there is no cure for Alzheimer’s disease and the treatment revolves around providing a safe environment for patients. Therapy is also effective in providing support, but scientists are racing to finally find a medicine for the condition.

What is Alzheimer’s disease?

Alzheimer’s disease is a type of dementia, which is a neurodegenerative disease. The disease is irreversible and progressive, which means that it worsens over time. The condition affects brain sections responsible for memory, thinking skills, and cognitive ability. In time, the symptoms worsen, often causing the inability to carry out the simplest tasks or activities of daily living.

The disease first appears in people who are in their mid-60s but can emerge earlier in some cases. Scientists don’t fully understand the exact cause of Alzheimer’s disease, but it may be a combination of various factors. These include age, since older adults are mostly affected, and hereditary because it can run in families. There is also evidences that changes in the brain starting even years before the start of the symptoms may have occurred.

https://pubs.rsc.org/en/Content/ArticleLanding/2020/CC/C9CC09170J#!divAbstract

New compound prevents amyloid formation to fight Alzheimer’s disease

Commonly used anti-inflammatory drug shows potential to treat Alzheimer's disease

A research project has shown that an experimental model of Alzheimer's disease can be successfully treated with a commonly used anti-inflammatory drug.

A team led by Dr David Brough from The University of Manchester found that the anti-inflammatory drug completely reversed memory loss and brain inflammation in mice.

Nearly everybody will at some point in their lives take non-steroidal anti-inflammatory drugs; mefenamic acid, a common Non-Steroidal Anti Inflammatory Drug (NSAID), is routinely used for period pain.

The findings are published today in a paper authored by Dr Brough and colleagues, in the respected journal Nature Communications. Dr Brough and Dr Catherine Lawrence supervised PhD student Mike Daniels, and postdoc Dr Jack Rivers-Auty who conducted most of the experiments.

Though this is the first time a drug has been shown to target this inflammatory pathway, highlighting its importance in the disease model, Dr Brough cautions that more research is needed to identify its impact on humans, and the long-term implications of its use.

The research, funded by the Medical Research Council and the Alzheimer's Society, paves the way for human trials which the team hope to conduct in the future.

Around 500,000 people in the UK have Alzheimer's disease which gets worse over time, affecting many aspects of their lives, including the ability to remember, think and make decisions.

In the study transgenic mice that develop symptoms of Alzheimer's disease were used. One group of 10 mice was treated with mefenamic acid, and 10 mice were treated in the same way with a placebo.

The mice were treated at a time when they had developed memory problems and the drug was given to them by a mini-pump implanted under the skin for one month.

Memory loss was completely reversed back to the levels seen in mice without the disease.

Dr Brough said: "There is experimental evidence now to strongly suggest that inflammation in the brain makes Alzheimer's disease worse.

"Our research shows for the first time that mefenamic acid, a simple Non-Steroidal Anti Inflammatory Drug can target an important inflammatory pathway called the NLRP3 inflammasome , which damages brain cells."

He added: "Until now, no drug has been available to target this pathway, so we are very excited by this result.

"However, much more work needs to be done until we can say with certainty that it will tackle the disease in humans as mouse models don't always faithfully replicate the human disease."Because this drug is already available and the toxicity and pharmacokinetics of the drug is known, the time for it to reach patients should, in theory, be shorter than if we were developing completely new drugs.

"We are now preparing applications to perform early phase II trials to determine a proof-of-concept that the molecules have an effect on neuroinflammation in humans."

Dr Doug Brown, Director of Research and Development at Alzheimer's Society, said: "Testing drugs already in use for other conditions is a priority for Alzheimer's Society - it could allow us to shortcut the fifteen years or so needed to develop a new dementia drug from scratch.

"These promising lab results identify a class of existing drugs that have potential to treat Alzheimer's disease by blocking a particular part of the immune response. However, these drugs are not without side effects and should not be taken for Alzheimer's disease at this stage - studies in people are needed first."

Commonly used anti-inflammatory drug shows potential to treat Alzheimer's disease

Experimental Alzheimer's drug reverses genetic changes thought to spur the disease

After treatment with riluzole, the brains of old rats showed more of a transporter molecule that removes excess glutamate, (green fluorescence, right) as compared to untreated rats (left).

Aging takes its toll on the brain, and the cells of the hippocampus--a brain region with circuitry crucial to learning and memory--are particularly vulnerable to changes that can lead to Alzheimer's disease or cognitive decline. With the hope of counteracting the changes that can lead to these two conditions, researchers at Rockefeller University and their colleagues have begun examining the effects of a drug known to affect this circuitry.

In new research described recently in Molecular Psychiatry, a team led by Ana Pereira, Instructor in Clinical Medicine in Bruce McEwen's laboratory found that the drug, riluzole, is capable of reversing key genetic changes associated with these conditions.

 riluzole

"In aging and Alzheimer's, the chemical signal glutamate can accumulate between neurons, damaging the circuitry," Pereira says. "When we treated rats with riluzole, we saw a suite of changes. Perhaps most significantly, expression of molecules responsible for clearing excess glutamate returned to more youthful levels."

Previous work in McEwen's lab by Pereira has shown that the drug prompted structural changes in rats' neurons that prevent the memory loss often seen in old animals. Pereira is currently testing riluzole for the first time in Alzheimer's patients in a clinical trial at the Rockefeller University Hospital.

Glutamate clean up

Generally, glutamate is released to excite other neurons and doesn't linger in the spaces between them. As we age, though, the system gets a little leaky and glutamate can build up in these intercellular spaces. This happens in part when neurons make less and less of the transporter molecule responsible for removing excess glutamate. When it accumulates, this essential neurotransmitter can cause big problems, damaging or killing neurons and so contributing to Alzheimer's disease, and other disorders.

Pereira and co-first author Jason Gray, a postdoc in the lab sought to better understand the molecular vulnerabilities of an aging glutamate system and riluzole's effect on it.

"The essence is we used a drug known to modulate glutamate, and when we gave it to old rats, we saw it reversed many of the changes that begin in middle age in the hippocampus," Gray says. "We saw a similar pattern when we compared the riluzole-induced changes to data from Alzheimer's patients--in a number of key pathways in the hippocampus, the drug produced an effect opposing that of the disease."

The drug, it turns out, modifies the activity of certain genes in an aged animal to resemble that of a younger rat. For example, the researchers found that the expression of a gene called EAAT2, which has been linked to Alzheimer's and is known to play a role in removing excess glutamate from nerve fibers, declines as the animals age. However, in rats treated with riluzole this gene's activity was brought back to its youthful levels.

New targets for treatments?

In addition to its potential ability to allay memory loss and cognitive decline, riluzole is attractive as a potential treatment for Alzheimer's. The drug is already being used to treat another neurological disease, amyotrophic lateral sclerosis, and is therefore considered relatively safe. In Pereira's ongoing clinical trial, patients with Alzheimer's disease have thus far been treated with either the drug or a placebo, and have been undergoing tests to help determine whether their brain functions have been improved.

"We hope to use a medication to break the cycle of toxicity by which glutamate can damage the neurons that use it as a neurotransmitter, and our studies so far suggest that riluzole may be able to accomplish this," Pereira says. "We found that in addition to recovering the expression of EAAT2, the drug restored genes critical for neural communication and plasticity, both of which decline with aging and even more significantly in Alzheimer's disease."

The findings also help to lay the groundwork for further study of glutamate transporters as potential targets for treating both conditions.

Ref : http://newswire.rockefeller.edu/2016/05/02/an-experimental-alzheimers-drug-reverses-genetic-changes-thought-to-spur-the-disease/

Ref : http://www.nature.com/mp/journal/vaop/ncurrent/full/mp201633a.html

Experimental Alzheimer's drug reverses genetic changes thought to spur the disease  

New key factor (ßCTF, a small protein found in APP) identified in the development of Alzheimer's disease...

Inheritance of an extra copy of the gene- β -amyloid precursor protein, APP, in individuals with Down syndrome leads to the inevitable development of early onset Alzheimer's disease, known to be linked to the deposition of Amyloid β peptide or Aβ in the brain. However, a new study published online by Proceedings of the National Academy of Sciences identifies βCTF, a small protein found in APP, as a novel factor for the development of Alzheimer's disease related endosome abnormalities, which have also been tied previously to the loss of brain cells in Alzheimer's disease.

In their study, using the cells from individuals with Down syndrome that are genetically predisposed to developing Alzheimer's disease, the researchers showed that elevated levels of ßCTF, independent of Aß, cause a specific pattern of endosome defects with similar pathology of brain cells in Alzheimer's disease. As per the claim by Dr. Ying Jiang, (Department of Psychiatry at NYU Langone Medical Center. they were successfully able to pinpoint that ßCTF causes Alzheimer's disease-related endosome defects and successfully reverse these endosome defects by lowering ßCTF levels in the cells. Hope this study demonstrating an alternative protein factor, ßCTF, derived from the gene APP, is also unequivocally involved in Alzheimer's disease and may be of additional importance for the development of future effective therapies in the days to come...

New drug appears to decrease inflammation in the brain linked to Alzheimer's disease

An experimental drug shows promise in treating Alzheimer's disease by preventing inflammation and removing abnormal protein clumps in the brain that are associated with the disease, suggests a study in mice presented at the ANESTHESIOLOGY® 2016 annual meeting.

A key characteristic of Alzheimer's disease is the development of abnormal protein clumps called amyloid plaques and tangled bundles of fibers in the brain. These changes cause inflammation in the brain and damage to the neurons. This progressive damage leads to memory loss, confusion and dementia. The new drug, known as NTRX-07, appears to decrease this inflammation in the brain, while preserving neurons and regenerative cells in the brain.

"This drug may reduce inflammation in the brain, which is linked to Alzheimer's disease," said lead researcher Mohamed Naguib, M.D., a physician anesthesiologist in the Department of General Anesthesiology at the Cleveland Clinic and professor of anesthesiology at the Cleveland Clinic Lerner College of Medicine. "NTRX-07 uses a different mechanism than many other Alzheimer's drugs currently available, as it targets the cause of the disease, not just the symptoms."

The authors discovered NTRX -07's memory-restoring abilities while studying the drug's potential to treat a complex, chronic pain condition called neuropathic pain. "Patients who have neuropathic pain have chronic neuroinflammation," said Dr. Naguib. "This is a compound that blunts that inflammation."

Researchers tested NTRX -07 on mice bred to have similar brain neurodegenerative issues as seen in Alzheimer's. They found that inflammation produced in response to the disease caused changes in the brain's microglia cells - immune cells that typically remove dangerous amyloid plaques (protein clumps) in the brain. As the amyloid plaques accumulated in the mice, the microglia (immune cells) were unable to remove them, leading to inflammation and damage to nerve cells, which caused decreased cognitive ability.

Microglia cells have receptors on the surface called CB2 receptors, which when activated can produce an anti-inflammatory response. NTRX -07 targets CB2 receptors, which leads to decreased inflammation and prevents damage to the brain tissue. The new drug improved removal of abnormal amyloid plaques and improved memory performance and other cognitive skills.

The drug also increased levels of a protein called SOX2, which has been shown to help new brain cells develop and protect the brain in people with Alzheimer's disease. The study found in mice treated with NTRX-07, the levels of SOX2 were restored to normal levels. In contrast, mice treated with a placebo showed decreased levels of SOX2, active inflammation in the brain, poor removal of amyloid plaques, and poor memory performance.

Compound prevents neurological damage, shows cognitive benefits in mouse model of Alzheimer’s disease

The supplement nicotinamide riboside (NR) – a form of vitamin B3 – prevented neurological damage and improved cognitive and physical function in a new mouse model of Alzheimer’s disease. The results of the study, conducted by researchers at the National Institute on Aging (NIA) part of the National Institutes of Health, suggest a potential new target for treating Alzheimer’s disease. The findings appear in the Feb. 5, 2018, issue of Proceedings of the National Academy of Sciences.

NR acts on the brain by normalizing levels of nicotinamide adenine dinucleotide (NAD+), a metabolite vital to cellular energy, stem cell self-renewal, resistance to neuronal stress and DNA repair. In Alzheimer’s disease, the brain’s usual DNA repair activity is impaired, leading to mitochondrial dysfunction, lower neuron production, and increased neuronal dysfunction and inflammation.

“The pursuit of interventions to prevent or delay Alzheimer’s and related dementias is an important national priority,” said Richard J. Hodes, M.D., director of the NIA. “We are encouraging the testing of a variety of new approaches, and this study’s positive results suggest one avenue to pursue further.”

The international team of scientists was led by Vilhelm A. Bohr, M.D., Ph.D., senior investigator and chief of the Laboratory of Molecular Gerontology of the NIA’s Intramural Research Program, with Dr. Yujun Hou, a postdoctoral investigator in the laboratory.

Based on their studies in human postmortem brain, they developed a new strain of mice mimicking major features of human Alzheimer’s such as tau pathology, failing synapses, neuronal death and cognitive impairment. Using this animal model, the researchers tested the effects of an NR supplement by adding it to the drinking water of the mice. Over a three-month period, researchers found that mice who received NR showed reduced tau in their brains, but no change in amyloid-beta.

The NR-treated mice also had less DNA damage, higher neuroplasticity (activity and reorganization of brain cells associated with learning or memory), increased production of new neurons from neuronal stem cells, and lower levels of neuronal damage and death. In the hippocampus area of the brain – in which damage and loss of volume is found in people with dementia – NR seemed to either clear existing DNA damage or prevent it from spreading further.

The NR-treated mice also performed better than control mice on multiple behavioral and memory tests, such as water mazes and object recognition. NR mice also showed better muscular and grip strength, higher endurance, and improved gait compared to their control counterparts. The research team believes that these physical and cognitive benefits are due to a rejuvenating effect NR had on stem cells in both muscle and brain tissue.

“We are encouraged by these findings that see an effect in this Alzheimer’s disease model,” said Dr. Bohr. “We are looking forward to further testing of how NR or similar compounds might be pursued for their possible therapeutic benefit for people with dementia.”

Next steps for the research team include further studies on the underlying mechanisms and preparations towards intervention in humans.

The team’s work also included contributions from researchers at the Danish Aging Research Center at the University of Aarhus, and the Center for Healthy Aging at the University of Copenhagen. The Bohr lab has a Cooperative Research and Development Agreement -- which allows NIH investigators to join colleagues from industry and academia to pursue common research goals -- with ChromaDex Corp.

Compound prevents neurological damage, shows cognitive benefits in mouse model of Alzheimer’s disease

First patients screened in Axovant's phase 3 study of RVT-101

Axovant Sciences Ltd. (NYSE: AXON), a leading clinical-stage biopharmaceutical company focused on the treatment of dementia, recently announced the first patients screened in MINDSET, a confirmatory global phase 3 study of Axovant's lead product candidate, RVT-101. Axovant also announced that the company and the U.S. Food and Drug Administration (FDA) have agreed to a Special Protocol Assessment (SPA) supporting this phase 3 program.

MINDSET is an international, multi-center, double blind, placebo-controlled study designed to evaluate the safety, tolerability and efficacy of RVT-101 in patients with mild-to-moderate Alzheimer's disease. The 24-week trial will compare 35-mg, once-daily oral doses of RVT-101 to placebo in approximately 1,150 patients with mild-to-moderate Alzheimer's disease on a stable background of donepezil therapy. The primary efficacy evaluations are the Alzheimer's Disease Assessment Scale – cognitive subscale (ADAS-cog) and the Alzheimer's Disease Cooperative Study – Activities of Daily Living scale (ADCS-ADL), each of which have been used as endpoints to obtain regulatory approval of currently-marketed Alzheimer's disease treatments in the United States and Europe.

The MINDSET trial is designed to confirm the results of a 684-patient international, multi-center, double-blind placebo-controlled study in which patients on a stable background of donepezil therapy receiving 35 mg RVT-101 demonstrated statistically significant improvements on the ADAS-cog and ADCS-ADL as compared to patients receiving donepezil alone.

"I am grateful for the unwavering efforts of the entire development team that has so rapidly advanced RVT-101 into this final stage of the drug development process," said Axovant Chief Development Officer Dr. Lawrence Friedhoff, who is leading the RVT-101 development program and previously led the development program for donepezil (brand name Aricept®), the most widely used Alzheimer's treatment.

"No new compounds have been approved for Alzheimer's disease in over a decade, and physicians are scrambling to do more for their patients," said Dr. Gary Small, President of the American Association for Geriatric Psychiatry. "We need well-tolerated, once-daily oral treatments that provide clinically meaningful benefits. The start of the MINDSET study is an important milestone for the field of Alzheimer's drug development."

First patients screened in Axovant's phase 3 study of RVT-101

Donepezil hydrochloride for Dementia Related to Alzheimer's Disease...

We know that, ARICEPT® [donepezil hydrochloride, see structure  (source-chemSpider) ] is a reversible inhibitor of the enzyme acetylcholinesterase, known chemically as (±)-2,3-dihydro-5,6-dimethoxy-2 -[[1-(phenylmethyl)-4-piperidinyl]- methyl]-1H-inden-1-one hydrochloride. Donepezil hydrochloride is commonly referred to in the pharmacological literature as E2020.

Acetylcholinesterase is the target of many Alzheimer's Dementia drugs , nerve gases, particularly the organophosphates (e.g. Sarin) and insecticides (e.g. carbaryl). These agents — known as cholinesterase inhibitors — block the function of acetylcholinesterase and thus cause excessive acetylcholine to accumulate in the synaptic cleft. The excess acetylcholine causes neuromuscular paralysis (i.e. interminable muscle contractions) throughout the entire body, leading to death by asphyxiation.

The U.S. Food and Drug Administration approved the first generic versions of Aricept (donepezil hydrochloride) orally disintegrating tablets on Dec. 11. Donepezil hydrochloride is indicated for the treatment of dementia related to Alzheimer's disease. Orally disintegrating tablets dissolve on the tongue, without having to be swallowed whole. This may make it easier to take the medication for older or disabled patients who have difficulty swallowing.

Alzheimer's disease :

Alzheimer's disease is an irreversible, progressive brain disease that slowly destroys memory and thinking skills and, eventually, the ability to carry out the simplest tasks of daily living. In most people with Alzheimer's disease, symptoms first appear after age 60. Alzheimer's disease is the most common cause of dementia among older people, but it is not a normal part of aging...

Ref : http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm194173.htm

New small-molecule drug restores brain function, memory in mouse model of Alzheimer's disease

In continuation of my update  on canola oil

An international team of researchers has shown that a new small-molecule drug can restore brain function and memory in a mouse model of Alzheimer's disease. The drug works by stopping toxic ion flow in the brain that is known to trigger nerve cell death. Scientists envision that this drug could be used to treat Alzheimer's and other neurodegenerative diseases such as Parkinson's and ALS.

"This is the first drug molecule that can regulate memory loss by directly blocking ions from leaking through nerve cell membranes," said Ratnesh Lal, a professor of bioengineering at the University of California San Diego and co-senior author of the study.

Various studies have linked Alzheimer's disease to the accumulation of two particular proteins in the brain called amyloid-beta and tau. One theory is that these protein clusters create pores in nerve cell membranes that allow ions to travel in and out uncontrollably. This would alter ion levels inside the cells and in turn trigger neuronal dysfunction and cell death.

The new drug, a small molecule called anle138b, blocks these pores from moving ions in and out of nerve cells. Anle138b attaches to both amyloid-beta and tau protein clusters and deactivates the pores created by these clusters.

Researchers administered anle138b to mice with a genetic predisposition for developing an Alzheimer's-like condition. The mice had symptoms such as abnormal brain function, impaired memory and high levels of either amyloid-beta or tau proteins in the brain. Treatment with anle138b normalized brain activity and improved learning ability in mice.

The study was led by the German Center for Neurodegenerative Diseases, the University Medical Center Göttingen, the Braunschweig University of Technology, the Max Planck Institute for Biophysical Chemistry, the Center for Nanoscale Microscopy and Molecular Physiology of the Brain in Göttingen, Germany, and the University of California San Diego. Researchers published their findings on Dec. 5 in EMBO Molecular Medicine.

Christian Griesinger, a professor at the Max Planck Institute for Biophysical Chemistry and co-senior author of the study, noted, "The drug is able to reach the brain when taken orally. Therefore, it is easy to administer, and we are currently performing toxicology studies to eventually be able to apply anle138b to humans."

The team cautions that since the drug has so far only been tested in mice, it is unclear how well it would perform in humans. "I would like to emphasize that none of the current animal models fully recapitulate the symptoms seen in Alzheimer's patients. Thus, care has to be taken when interpreting such data. However, our study offers evidence that anle138b has potential for neuroprotection," said André Fischer, a senior researcher at the German Center for Neurodegenerative Diseases and the University Medical Center Göttingen, who is also a co-senior author of the study.

While collaborators in Germany will be pursuing clinical studies in human patients with neurodegenerative diseases, Lal and his research group at the UC San Diego Jacobs School of Engineering are particularly interested in testing anle138b on a variety of other diseases that are linked to toxic ion flow caused by amyloid proteins, including diabetes, tuberculosis and certain types of cancer. Lal's group has performed extensive research on amyloid ion channels and their roles in these diseases. "Blocking the ion leakiness of amyloid channels using anle138b could be an effective therapy for various diseases," Lal said.

Lal serves as co-director for the Center of Excellence for Nanomedicine and Engineering, a subcenter of the Institute of Engineering in Medicine at UC San Diego. His research group will also work on targeted delivery of the drug using their patent pending "nanobowls," which are magnetically guided nanoparticles that can be packed with drugs and diagnostic molecules, deliver them to particular sites in the body and release them on demand. Future studies will focus on using these nanobowls to deliver anle138b to the brain, as well as other diseased tissues and organs affected by toxic amyloid-beta ion channels.

http://ucsdnews.ucsd.edu/pressrelease/experimental_drug_block_toxic_ion_flow_linked_to_alzheimers_disease

New small-molecule drug restores brain function, memory in mouse model of Alzheimer's disease

FDA's approval of phase II clinical trials of Bryostatin ( Alzheimer's disease)...

Bryostatins are a group of macrolide lactones first discovered in the late 1960s in a species of bryozoan, Bugula neritina. It is believed to be produced by symbiont bacteriato protect the bryozoan larva from predation or infection, they have cytotoxic properties and are under investigation as anti-cancer agents and as a memory enhancement agent. Bryostatin in sub-nanomolar concentrations has been shown to be a potent activator of protein kinase C.

Bryostatin has appeared very promising enhancing memory in animal models. Bryostatin was able to increase the duration of memory retention of the marine slug Hermissenda crassicornis by over 500%, and was able to dramatically increase the rate of learning in rats. Bryostatin is thought to potentiate memory by activating PKC. Animal tests suggest it may alleviate brain damage after stroke if administered within 24hrs.

Bryostatin was originally created as an anti-cancer chemotherapy. When BRNI scientists extensively tested PKC activators against Alzheimer's disease models, they discovered the drug's hidden potential to stop Alzheimer's disease. Over the past six years, the drug has shown remarkable possibilities. In preclinical testing, BRNI scientists experimented with Bryostatin on three species of Alzheimer's disease transgenic mice, each species based on different human Alzheimer's disease genes. The test results revealed that Bryostatin, and a related class of drugs discovered at BRNI, can reduce the toxic Alzheimer's disease protein A Beta, restore lost synapses, and protect against the loss of memory functions. In related preclinical testing, Bryostatin has been shown to enhance and restore memory by rewiring connections in the brain previously destroyed by stroke, head trauma, or aging itself. With FDAs approval for the phase II clinical trials, this will go a long way in the history of drug research. Bryostatin trial on Alzheimer's disease patients represents a new direction for the treatment of a disease with no current cure. Congrats Dr. Daniel Alkon (Scientific Director of BRNI) and his group...

New heart failure drug may increase patients' risk of Alzheimer's disease, macular degeneration

In continuation of my update on sacubitril and Valsartan

Patients with mild heart failure stand to benefit from a new drug that can halt the progression of their disease and reduce their risk of cardiovascular-related death. But the drug -- a tablet that combines the agents valsartan and sacubitril, sold under the trade name Entresto by drugmaker Novartis -- may be too good to be true, according to Arthur M. Feldman, MD, PhD, Executive Dean of the Lewis Katz School of Medicine at Temple University (LKSOM), Chief Academic Officer of the Temple University Health System, and Laura H. Carnell Professor of Medicine at LKSOM.

In an article published online December 7th in the Journal of the American Medical Association, Dr. Feldman and colleagues at Thomas Jefferson University and the University of Florida warn that valsartan/sacubitril could theoretically increase patients' risk of Alzheimer's disease and macular degeneration, a blinding condition affecting the retina of the eye. The article raises these concerns about the drug, which was approved by the U.S. Food and Drug Administration in July 2015.

"Basic science data has caused us to speculate that off-target effects of valsartan/sacubitril may cause an exacerbation of Alzheimer's disease and could also exacerbate the course of macular degeneration," Dr. Feldman explained.

Dr. Feldman went on to note that "doctors are prescribing these drugs without knowledge of these theoretical risks."

Valsartan/sacubitril works by inhibiting an enzyme known as neprilysin, which normally plays a critical role in breaking down a wide array of peptides in cells. Among those substances are the so-called natriuretic peptides, which function in regulating scarring and cell growth in the heart when neprilysin is blocked. Because of those activities, valsartan/sacubitril can delay the progression of heart failure in some patients.

Neprilysin, however, also normally degrades amyloid beta, a peptide that can accumulate in the brain, where it contributes to Alzheimer's disease, as well as in the eye, where it is implicated in macular degeneration. The balance between the production and clearance of amyloid beta is crucial to the pathogenesis of Alzheimer's disease and is suspected to influence the development of macular degeneration. In animal models, blocking neprilysin disturbs that balance and exacerbates the development of Alzheimer's pathology.

New heart failure drug may increase patients' risk of Alzheimer's disease, macular degeneration