Yearly Archives: 2014

Research implicates new player in Alzheimer’s and other dementias.

More than a century of research into the causes of dementia has focused on the clumps and tangles of abnormal proteins that appear in the brains of people with neurodegenerative diseases. However, scientists know that at least one piece of the puzzle has been missing because some people with these abnormal protein clumps show few or no signs of cognitive decline.

A new study offers an explanation for these longstanding mysteries. Researchers have discovered that a gene regulator active during fetal brain development, called REST, switches back on later in life to protect aging neurons from various stresses, including the toxic effects of abnormal proteins. The researchers also showed that REST is lost in critical brain regions of people with Alzheimer’s and mild cognitive impairment.

“Our work raises the possibility that the abnormal protein aggregates associated with Alzheimer’s and other neurodegenerative diseases may not be sufficient to cause dementia; you may also need a failure of the brain’s stress response system,” said Bruce Yankner, Harvard Medical School professor of genetics and leader of the study.

The results were published in the Mar 19th edition of Nature Magazine.

Source: Medical Express (Stephanie Dutchen)

Quality of life (QoL) improves under subthalamic deep brain stimulation (STN-DBS) in Parkinson’s disease (PD), whereas social functioning may be disrupted. This disruption could negatively influence the family dynamic, leading to different perceptions of the STN-DBS outcome by patients and caregivers.

A recent study, published in the March 17th edition of Parkinsonism & Related Disorders, demonstrated unequal perception of QoL between patients and caregivers under STN-DBS. The fact that social functioning did not improve longitudinally iin the study was suggested to be due to patient’s higher levels of apathy and reduced motivation following surgery. These findings stress the importance of considering caregiver’s input in DBS patients’ outcomes and the need for pre-operative preparation.

Source: European Parkinson’s Disease Association

Researchers have long been searching for a blood-based test that could predict Alzheimer’s disease. In the March 9 Nature Medicine, researchers report that a panel of 10 lipids could one day fit the bill.

In a small study, plasma levels of these lipids distinguished, with 90 percent accuracy, who would develop cognitive impairment over the next two to three years. If the results are confirmed in larger samples, it would encourage hopes for a blood test for Alzheimer’s. However, the authors stress that is still years away.

Numerous questions remain, including whether the observed lipid changes are specific to AD, or represent a more general marker for neurodegeneration. Despite this, the findings have generated excitement in the popular press, with numerous outlets touting the test as a potential AD diagnostic

Source: AlzForum

The latest research from the Alzheimer’s Association shows a woman’s lifetime risk of developing the neurodegenerative disease is one in six, compared with one in 11 for men.

Women are also shouldering the responsibility for caring for parents affected by Alzheimer’s. More than twice as many women as men provide 24-hour care for a loved one with the disease, and twice as many women as men gave up working full time in order to do so. The full 2014 Alzheimer’s Disease Facts and Figures report can be downloaded at the link below.

Source: Alzheimer Association

A new ADI report highlights that undernutrition is a major problem among people with dementia and stresses the importance of recognising nutrition as a potential key factor in the wellbeing of people with dementia.

Research reviewed in the report finds that 20-45% of those with dementia in the community experience clinically significant weight loss over one year. The report reviews existing research on dietary factors across the life course that might increase or decrease the risk of developing dementia in later life. While obesity in mid-life may be a risk factor for developing dementia in late life, weight loss tends to become a more significant issue in the decade leading up to the clinical onset of the disease and accelerates thereafter.

The report also details actions that could improve the nutrition of people with dementia through diet and external factors such as modifying the mealtime environment, and supporting and training carers. Given the evidence for effective interventions, there is much untapped potential to improve the food intake and nutritional status of people with dementia.

Source: Alzheimer Disease International

A more intensive exercise program specifically designed for people in hospital with dementia has been shown to add benefits over normal rehabilitation.

The study was published in theFebruary 2014 issue of the Journal of Alzheimer’s Disease (requires subscription to view full article).

A pre-press version of “An Intensive Exercise Program Improves Motor Performances in Patients with Dementia: Translational Model of Geriatric Rehabilitation at the links below:

The underlying genetics of neurodegenerative disorders tend not to be well understood. This study links HSP to other neurodegenerative disorders and can potentially facilitate further gene discovery and mechanistic understanding of neurodegenerative diseases.

Hereditary spastic paraplegias (HSPs) are neurodegenerative motor neuron diseases characterized by progressive age-dependent loss of corticospinal motor tract function.

In this study, researchers investigated the underlying genetics of hereditary spastic paraplegia (HSP), a human neurodegenerative disease, by sequencing the exomes of individuals with recessive neurological disorders. Loss-of-function gene mutations in both novel genes and genes previously implicated for this condition were identified, and several were functionally validated. 

Source:  Science Magazine (requires subscription to view full article)

The word “chaperone” refers to an adult who keeps teenagers from acting up at a dance or overnight trip. It also describes a type of protein that can guard the brain against its own troublemakers: misfolded proteins that are involved in several neurodegenerative diseases.

Researchers at Emory University School of Medicine have demonstrated that as animals age, their brains are more vulnerable to misfolded proteins, partly because of a decline in chaperone activity.

The researchers were studying a model of spinocerebellar ataxia, but the findings have implications for understanding other diseases, such as Alzheimer’s, Parkinson’s and Huntington’s.

They also identified targets for potential therapies: bolstering levels of either a particular chaperone or a growth factor in brain cells can protect against the toxic effects of misfolded proteins.

The results were published in the journalNeuron.

Source:  Medical Express

A number of studies have shown that exercise can remodel the brain by prompting the creation of new brain cells and inducing other changes. Now it appears that inactivity, too, can remodel the brain, according to a new report.

The study, which was conducted in rats but likely has implications for people too, the researchers say, found that being sedentary changes the shape of certain neurons in ways that significantly affect not just the brain but the heart as well. The findings may help to explain, in part, why a sedentary lifestyle is so bad for us.

Source: New York Times Blogs

The phase 3 trial results of Eli Lilly and Co.’s solanezumab and Janssen/Pfizer’s bapineuzumab appeared in the January 23rd edition of the New England Journal of Medicine.

In an accompanying editorial in NEJM, JPND Scientific Advisory Board members Eric Karran of Alzheimer’s Research U.K., and John Hardy of University College London (neither of whom were involved in the trials), gave their insights into the results.

Both monoclonal antibodies failed to slow cognitive or functional decline in patients with mild to moderate Alzheimer’s disease. However, each drug hinted at smaller benefits and bolstered the idea that amyloid-related treatments, if they are to work, must be applied early in the disease process, perhaps before cognitive symptoms emerge.

Source:  AlzForum