Brain’s ‘insulation’ continues to form throughout life
Myelin acts as insulation for millions of brain cells, allowing for swift and efficient transmission of signals across brain regions. Despite its crucial role, little is known about how stable this structure is in the adult brain and what impact aging has on its maintenance. Yale neurologists Robert Hill, Alice Li, and Jaime Grutzendler devised techniques to track and precisely image myelin throughout the lifetime of the mouse. They discovered that myelin continues to form and restructure in the adult brain — indicating the potential for lifelong change. They also learned that during aging, myelin begins to deteriorate and myelin debris accumulate over time.
Barrier Function: TREM2 Helps Microglia to Compact Amyloid Plaques
New research bolsters the case that brain-derived microglia need TREM2 to essentially wall off amyloid plaques, but exactly how they do that remains up for debate. As reported in the May 18 Neuron, scientists led by Jaime Grutzendler at Yale University, New Haven, Connecticut, used confocal and super-resolution microscopy to show that TREM2-positive microglia surround and encase amyloid fibrils, protecting neurons in the process. Yet TREM2 itself appears to lend little support to phagocytosis of Aβ. The technical caliber of the work and the quality of the microscopy led researchers in the AD field to call the study “stunning.” It comes on the heels of another paper, in the April 18 Journal of Experimental Medicine, which suggests the microglia that surround plaques are brain-derived, not peripheral myeloid cells as others had suggested previously.Source: Barrier Function: TREM2 Helps Microglia to Compact Amyloid Plaques
Immune cells may act as ‘trash compactors, protecting against Alzheimer’s
In the battle against Alzheimer’s disease, inflammation may be an ally, not a foe, a new study has found. Immune cells in the brain previously blamed for Alzheimer’s actually protect against the disease by corralling the damage-causing amyloid plaques, according to the Yale University study, published Wednesday in the journal Neuron. The findings suggest that inflammation byproducts of these immune cells, known as microglia, probably don’t cause Alzheimer’s, nor are they as effective as previously believed at “gobbling up” the plaques, both of which have been hypothesized, said Jaime Grutzendler,associate professor of neurology and neuroscience and the study’s lead author. Rather, he said, the cells act as a physicalbarrier that encloses the spiky plaques, preventing outward expansion and making them less toxic. “They’re sort of like garbage compactors,” he said. “They tightly surround the plaques and make them inert and less damaging . . . by creating a capsule.”
Research in the news: Hyperactive neurons may be culprit in Alzheimer’s
A long-term reduction in neuronal activity reduces amyloid plaques associated with Alzheimer’s disease, Yale University researchers have found. The study, using mouse models of Alzheimer’s, found the opposite is also true — triggering an increase in neuronal activity spurs creation of plaques and toxic amyloid beta peptides believed to trigger the disease.
Immune cells are an ally, not enemy, in battle against Alzheimer’s
In Alzheimer’s disease (AD), β-amyloid plaques are tightly enveloped by microglia but the significance of this phenomenon is unknown. Here the authors used confocal and in vivo two-photon imaging in AD mouse models and revealed that microglia constitute a physical barrier that prevents the formation of neurotoxic hotspots of protofibrillar β-amyloid and shields adjacent neurons and synapses from the toxic effect of amyloid plaques
Introducing New Additions to the Outreach and Engagement Core of the Alzheimer's Disease Research Center
Carmen I. Carrión, Psy.D. has joined the ORE as an Associate Core Leader, joining Isis Burgos-Chapman, MD. Dr. Carrión is an Assistant Professor and a bilingual (Spanish) neuropsychologist in the department of Neurology.
What to Do About Aducanumab? Academic Memory Programs Brace for the Tough Questions
Academic medical centers are establishing committees and workgroups to develop standards and criteria for determining eligibility for the newly-approved and controversial Alzheimer's drug, aducanumab.Source: NeurologyToday
FDA calls for federal investigation into its controversial Alzheimer’s drug approval
The head of the Food and Drug Administration has called for a wide-ranging federal investigation into the approval of Biogen’s treatment for Alzheimer’s disease just one month after a decision that sparked the ire of lawmakers, doctors, and public health advocates.Source: STAT News
SLEEP-SMART Intervention Shows Promising Results for Women Suffering from Sleeping Problems, Depression, and Anxiety
Preliminary data indicate SLEEP-SMART can improve sleep patterns, show associated reductions in symptoms of depression and anxiety, and improve the functioning of brain circuits important in emotional and cognitive health.
Research Begun by WHRY Continues to Show Possible Pathway to Derail Dementia
Research is revealing the mechanisms that underlie the role of estradiol in memory so that next generation treatments for Alzheimer's disease and other dementias can specifically target these mechanisms and avoid the potential for negative side effects of systemic estrogen therapy.