The time Anna stayed up all night

Almost precisely a decade ago, a young Atlanta lawyer named Anna was returning to work, after being treated for an extraordinary sleep disorder. Her story has been told here at Emory and by national media outlets. Fast forward a decade to Idiopathic Hypersomnia Awareness Week 2018 (September 3-9), organized by Hypersomnolence Australia. What this post deals with is essentially the correction of a date at the tail end of Anna’s story, but one with long-term implications Read more

Mini-monsters of cardiac regeneration

Jinhu Wang’s lab is not producing giant monsters. They are making fish with fluorescent hearts. Lots of cool Read more

Why is it so hard to do good science?

Last week, Lab Land put out a Twitter poll, touching on the cognitive distortions that make it difficult to do high-quality science. Lots of people (almost 50) responded! Thank you! We had to be vague about where all this came from, because it was before the publication of the underlying research paper. Ray Dingledine, in Emory’s Department of Pharmacology, asked us to do the Twitter poll first, to see what answers people would give. Dingledine’s Read more

norepinephrine

The blue spot: where seeds of destruction begin

Neuroscientist and geneticist David Weinshenker makes a case that the locus coeruleus (LC), a small region of the brainstem and part of the pons, is among the earliest regions to show signs of degeneration in both Alzheimer’s and Parkinson’s disease. You can check it out in Trends in Neurosciences.

The LC is the main source of the neurotransmitter norepinephrine in the brain, and gets its name (Latin for “blue spot”) from the pigment neuromelanin, which is formed as a byproduct of the synthesis of norepinephrine and its related neurotransmitter dopamine. The LC has connections all over the brain, and is thought to be involved in arousal and attention, stress responses, learning and memory, and the sleep-wake cycle.

Cells in the locus coeruleus are lost in mild cognitive impairment and Alzheimer’s. From Kelly et al Acta Neuropath. Comm. (2017) via Creative Commons

The protein tau is one of the toxic proteins tied to Alzheimer’s, and it forms intracellular tangles. Pathologists have observed that precursors to tau tangles can be found in the LC in apparently healthy people before anywhere else in the brain, sometimes during the first few decades of life, Weinshenker writes. A similar bad actor in Parkinson’s, alpha-synuclein, can also be detected in the LC before other parts of the brain that are well known for damage in Parkinson’s, such as the dopamine neurons in the substantia nigra.

“The LC is the earliest site to show tau pathology in AD and one of the earliest (but not the earliest) site to show alpha-synuclein pathology in PD,” Weinshenker tells Lab Land. “The degeneration of the cells in both these diseases is more gradual. It probably starts in the terminals/fibers and eventually the cell bodies die.” Read more

Posted on by Quinn Eastman in Neuro Leave a comment

Explainer: the locus coeruleus

The locus coeruleus is a part of the brain that has been getting a lot of attention recently from Emory neuroscience researchers.

The locus coeruleus is the biggest source of the neurotransmitter norepinephrine in the brain. Located deep in the brainstem, it has connections all over the brain, and is thought to be involved in arousal and attention, stress, memory, the sleep-wake cycle and balance.

Researchers interested in neurodegenerative disease want to look at the locus coeruleus because it may be one of the first structures to degenerate in diseases such as Alzheimer’s and Parkinson’s. In particular, the influential studies of German neuro-anatomist Heiko Braak highlight the locus coeruleus as a key “canary in the coal mine” indicator of neurodegeneration.

That’s why neurologist Dan Huddleston, working with biomedical imaging specialists Xiangchuan Chen and Xiaoping Hu and colleagues at Emory, has been developing a method for estimating the volume of the locus coeruleus by magnetic resonance imaging (MRI). Their procedure uses MRI tuned in such a way to detect the pigment neuromelanin (see panel), which accumulate in both the locus coeruleus and in the substantia nigra. Read more

Posted on by Quinn Eastman in Neuro Leave a comment

Study: Regular aerobic exercise and prevention of drug abuse relapse

Exercise provides health benefits

Researchers at Emory University and the University of Georgia have received funding from the National Institutes of Health to study the neurobiological mechanisms for how regular aerobic exercise may prevent drug abuse relapse. The grant is for $1.9 million over the next five years.

David Weinshenker, PhD, associate professor of human genetics, Emory School of Medicine, is a co-principal investigator on the project.

David Weinshenker, PhD

“This research will provide new insight into how regular exercise may attenuate drug abuse in humans,” Weinshenker says “More importantly, it may reveal a neural mechanism through which exercise may prevent the relapse into drug-seeking behavior.”

During the study, Weinshenker and UGA co-investigator Philip Holmes, professor of psychology in the Franklin College of Arts and Sciences, will measure exercise-induced increases of the galanin gene activity in the rat brain.

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Posted on by sgoodwin in Uncategorized Leave a comment