Study suggests how high blood pressure might contribute to Alzheimer’s
Monday, January 28, 2019
The brain’s system for removing waste is driven primarily by the pulsations of adjoining arteries, University of Rochester neuroscientists and mechanical engineers report in a new study. They also show that changes in the pulsations caused by high blood pressure slow the removal of waste, reducing its efficiency.
This might explain the association between high blood pressure and Alzheimer’ disease, the researchers say. Alzheimer’s, the most common cause of dementia among older adults, is characterized by abnormal clumps and tangled bundles of fibers in the brain.
The study, reported in Nature Communications, builds upon groundbreaking discoveries about the brain’s waste removal system by Maiken Nedergaard, co-director of the University’s Center for Translational Neuromedicine. Nedergaard and her colleagues were the first to describe how cerebrospinal fluid is pumped into brain tissue and flushes away waste. Subsequent research by her team has shown that this glymphatic waste removal system is more active while we sleep and can be damaged by stroke and trauma.
This latest research shows “in much greater depth and much greater precision than before” how the glymphatic system functions in the perivascular spaces that surround arteries in the outer brain membrane, says Douglas Kelley, an assistant professor of mechanical engineering and an expert in fluid dynamics. His lab is collaborating with Nedergaard’s team as part of a $3.2 million National Institute on Aging grant.
For this study, Humberto Mestre, a PhD student in Nedergaard’s lab, injected minute particles in the cerebrospinal fluid of mice, and then used two-photon microscopy to create videos showing the particles as they moved through the perivascular spaces.Read More: Study suggests how high blood pressure might contribute to Alzheimer’s
How to Get Enough Sleep in 2019
Friday, January 18, 2019
What really happens when you sleep? You may be taking a break from consciousness when you snooze, but not all of your neurons are resting, Veasey says. While you rest, your brain solidifies the synapses involved in the important memories you want to keep (like the name of your new dentist) while pruning the synapses involved in less important memories (such as where you put your keys two nights ago).
Sleep also gives your brain a chance to clear out debris that accumulated during the day. In 2014, a team of scientists led by Maiken Nedergaard at the University of Rochester Medical Center published research suggesting that the brain rids itself of metabolic waste through a kind of plumbing system that works mainly while we sleep. Just as the lymphatic system clears unwanted waste from the rest of the body, what’s called the glymphatic system eliminates debris and toxins from the brain and the central nervous system. Skimp on sleep, and this janitorial service can’t keep up, so the rubbish starts to accumulate in your noggin.Read More: How to Get Enough Sleep in 2019