Alzheimer's drug may reduce addictive and impulsive behavior associated with binge eating

In continuation of my update on Memantine

The Alzheimer's drug memantine may perform double-duty helping binge eaters control their compulsion. Researchers have demonstrated that memantine, a neuroprotective drug, may reduce the addictive and impulsive behavior associated with binge eating.

The Boston University School of Medicine (BUSM) study, which appears online inNeuopsychopharmacology, also found that a specific area in the brain, the nucleus accumbens, which is responsible for addictive behaviors, facilitates the effects of memantine.

Binge-eating disorder is a prevalent illness in America, affecting more than 10 million people. It is characterized by periods of excessive uncontrolled consumption of food, followed by uncomfortable fullness and feelings of self-disgust. New evidence indicates that changes in brain chemistry reflecting the addictive nature of binge eating may parallel drug and alcohol addiction.

Using an experimental model to simulate binge-eating behavior, researchers were able to identify the area of the brain associated with binge-eating and then suppress the behavior by applying memantine directly into that area.

"We found that memantine, which blocks glutamate NMDA receptors, blocks binge eating of junk food, blocks the strength of cues associated with junk food and blocks the compulsivity associated with binge eating," explained senior author Pietro Cottone, PhD, an associate professor of pharmacology and psychiatry at BUSM and co-director of the Laboratory of Addictive Disorders.

This research opens new avenues for binge eating treatment especially since memantine is a drug already approved for other indications. "Individuals with binge eating disorder have a very poor quality of life and decreased lifespan. Our study gives a better understanding of the underpinning neurobiological mechanisms of the disorder," added coauthor Valentina Sabino, PhD, assistant professor of pharmacology and psychiatry at BUSM and co-director of the Laboratory of Addictive Disorders.

Alzheimer's drug may reduce addictive and impulsive behavior associated with binge eating

Memantine for Huntington's disease ?

Memantine is the first in a novel class of Alzheimer's disease medications acting on the glutamatergic system by blocking NMDA glutamate receptors. Memantine is marketed under the brands Axura and Akatinol by Merz, Namenda by Forest, Ebixa and Abixa by Lundbeck and Memox by Unipharm.

Now researchers from Burnham & University of California have found that, Memantine, which is approved to treat Alzheimer's disease, successfully treated Huntington's disease in a mouse model by preserving normal synaptic electrical activity and suppressing excessive extrasynaptic electrical activity.

Huntington's disease is a hereditary condition caused by a mutated huntingtin gene that creates a misfolded, and therefore dysfunctional, protein. The new research shows that normal synaptic receptor activity makes nerve cells more resistant to the mutant proteins. However, excessive extrasynaptic activity contributed to increased nerve cell death. The research team found that low doses of Memantine reduce extrasynaptic activity without impairing protective synaptic activity.

This finding is of great importance because of the fact that chronic neurodegenerative diseases like Huntington's, Alzheimer's and Parkinson's are all related to protein misfolding and the researchers have shown for the first time that that electrical activity controls protein folding, and if one has a drug that can adjust the electrical activity to the correct levels, one can protect against misfolding and also the research verifies that appropriate electrical activity is protective. They also found that normal synaptic activity was protective. Subsequently, they treated Huntington's disease model mice with both high and low doses of Memantine and found that the low doses were protective by blocking pathological extrasynaptic activity, while high-dose Memantine encouraged disease progression because it also blocked the protective synaptic NMDA receptor activity. Its really good achievement congratulations. After having small clinical trials, larger, international clinical trials are now being planned....


Source : http://www.eurekalert.org/pub_releases/2009-11/bi-rfp111309.php.

Memantine, Drug Shown to Improve Memory in Those With Down Syndrome

In continuation of my update on  memantine

Costa, an associate professor of medicine, and his colleagues studied 38 adolescents and young adults with Down syndrome. Half took the drug memantine, used to treat Alzheimer's disease, and the others took a placebo.

Costa's research team hypothesized that memantine, which improved memory in mice with Down syndrome, could increase test scores of young adults with the disorder in the area of spatial and episodic memory, functions associated with the hippocampus region of the brain.

Participants underwent a 16-week course of either memantine or a placebo while scientists compared the adaptive and cognitive function of the two groups.

While they found no major difference between the groups in adaptive and most measures of cognitive ability, researchers discovered that those taking memantine showed significant improvement in verbal episodic memory. One of the lowest functioning individuals in the study saw a ten-fold increase in memory skills.

"People who took the medicine and memorized long lists of words did significantly better than those who took the placebo," said Costa, a neuroscientist specializing in Down syndrome research. "This is a first step in a longer quest to see how we can improve the quality of life for those with Down syndrome."

Translational Psychiatry - Antagonism of NMDA receptors as a potential treatment for Down syndrome: a pilot randomized controlled trial

Dementia drug 'keeps patients out of nursing homes'

Donepezil is used to slow the decline of people with mild to moderate dementia.

But it tends not to be given to patients in the late stage of the disease, because of a lack of evidence that it helps.

However the study of 295 people led by University College London experts, has produced evidence that challenges that.

The participants were split into groups with some being given donepezil, some another dementia drug memantine and others a dummy pill, the journal Lancet Neurology reported.

Of those given donepezil, sold under the brand name Aricept, 20% were living in a nursing home within a year, compared to 37% of those not given it.

The study is part of a follow-up analysis of data first collected three years ago, which showed some improvement when the drug was given to people with moderate to late-stage dementia.

Benefits

Researchers said more investigation was needed to fully unpick the reasons for a nursing home admission.

But they said their study provided evidence that needed to be considered when it comes to prescribing practices.

Some 60,000 people in the UK take the drug which helps to maintain brain function and the ability to cope with everyday activities such as eating and dressing.

About 70% of older people in care homes and nursing homes have dementia - with the average cost of that care ranging between £30,732 and £34,424.

Although such care is means-tested, a large chunk of the cost is borne by the individual.

In comparison, a year's supply of donepezil can cost as little as £21.59, according to the Alzheimer's Society.

Lead researcher Prof Robert Howard said: "Our previous work showed that, even when patients had progressed to the moderate or severe stages of their dementia, continuing with donepezil treatment provided modest benefits in cognitive function and in how well people could perform their daily activities.

"Our new results show that these benefits translate into a delay in becoming dependent on residential care, an event that many people dread."

Dr Doug Brown, director of research and development at the Alzheimer's Society, which co-funded the trial together with the Medical Research Council (MRC), said: "These robust findings are of real significance to people with dementia who want to continue living at home for as long as possible. We urge clinicians to consider the implications of this research and adjust their prescribing patterns accordingly."

Ref : http://www.thelancet.com/journals/laneur/article/PIIS1474-4422(15)00258-6/abstract

Dementia drug 'keeps patients out of nursing homes'