Warren symposium follows legacy of geneticist giant

If we want to understand how the brain creates memories, and how genetic disorders distort the brain’s machinery, then the fragile X gene is an ideal place to start. That’s why the Stephen T. Warren Memorial Symposium, taking place November 28-29 at Emory, will be a significant event for those interested in neuroscience and genetics. Stephen T. Warren, 1953-2021 Warren, the founding chair of Emory’s Department of Human Genetics, led an international team that discovered Read more

Mutations in V-ATPase proton pump implicated in epilepsy syndrome

Why and how disrupting V-ATPase function leads to epilepsy, researchers are just starting to figure Read more

Tracing the start of COVID-19 in GA

At a time when COVID-19 appears to be receding in much of Georgia, it’s worth revisiting the start of the pandemic in early 2020. Emory virologist Anne Piantadosi and colleagues have a paper in Viral Evolution on the earliest SARS-CoV-2 genetic sequences detected in Georgia. Analyzing relationships between those virus sequences and samples from other states and countries can give us an idea about where the first COVID-19 infections in Georgia came from. We can draw Read more
•••

dopamine

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 July 3, 2018 by Quinn Eastman in Neuro Leave a comment

More pieces in Parkinson’s puzzle: VMAT2 and SV2C

The drug target VMAT2 has appeared in biomedical news lately because of a pair of FDA approvals. One medicine treats the iatrogenic movement disorder tardive dyskinesia, the first approved to do so, and the other is for symptoms of Huntington’s disease.

Gary Miller, PhD

When Emory folks see VMAT2, they should think of two things: the neurotransmitter dopamine, and Parkinson’s research conducted by Gary Miller and his colleagues. They have made a case that activators of VMAT2 would be beneficial in Parkinson’s, but the drugs in the news were inhibitors, and presumably would make Parkinson’s worse.

VMAT2 (vesicular monoamine transporter 2) is responsible for transporting dopamine into synaptic vesicles, tiny packages for delivery. As Miller’s lab has shown, mice deficient in VMAT2 can be a model for the non-motor and motor aspects of Parkinson’s. In these mice, not only are certain nervous system functions impaired, but the dopamine packaging problem inflicts damage on the neurons.

Miller’s more recent work on a related molecule called SV2C is puzzling, but intriguing. The gene encoding SV2C had attracted attention because of its connection to the striking ability of cigarette smoking to reduce Parkinson’s risk, possibly mediated by nicotine’s effect on dopamine in the brain.

I say puzzling because SV2C’s role in brain cells can’t be described as easily as VMAT2’s. Read more

Posted on May 10, 2017 by Quinn Eastman in Neuro Leave a comment

Insecticide-ADHD link, with caveats

Gary Miller’s lab at Emory was the launching pad for this study from Rutgers, published last week in the FASEB Journal, showing a potential connection between a common type of insecticide used at home and in agriculture, pyrethroids, and attention deficit hyperactivity disorder (ADHD).  Read more

Posted on February 4, 2015 by Quinn Eastman in Neuro Leave a comment

Lab Land looking back: Top ten themes for 2014

It is a privilege to work at Emory and learn about and report on so much quality biomedical research. I started to make a top 10 for 2014 and had too many favorites. After diverting some of these topics into the 2015 crystal ball, I corralled them into themes.
1. Cardiac cell therapy
PreSERVE AMI clinical trial led by cardiologist Arshed Quyyumi. Emory investigators developing a variety of approaches to cardiac cell therapy.
2. Mobilizing the body’s own regenerative potential
Ahsan Husain’s work on how young hearts grow. Shan Ping Yu’s lab using parathyroid hormone bone drug to mobilize cells for stroke treatment.
3. Epigenetics
Many colors in the epigenetic palette (hydroxymethylation). Valproate – epigenetic solvent (anti-seizure –> anti-cancer). Methylation in atherosclerosis model (Hanjoong Jo). How to write conservatively about epigenetics and epigenomics.
4. Parkinson’s disease therapeutic strategies
Container Store (Gary Miller, better packaging for dopamine could avoid stress to neurons).
Anti-inflammatory (Malu Tansey, anti-TNF decoy can pass blood-brain barrier).
5. Personal genomics/exome sequencing
Rare disease diagnosis featured in the New Yorker. Three–part series on patient with GRIN2A mutation.
6. Neurosurgeons, like Emory’s Robert Gross and Costas Hadjpanayis, do amazing things
7. Fun vs no fun
Fun = writing about Omar from The Wire in the context of drug discovery.
No fun (but deeply moving) = talking with patients fighting glioblastoma.
8. The hypersomnia field is waking up
Our Web expert tells me this was Lab Land’s most widely read post last year.
9. Fine-tuning approaches to cancer
Image guided cancer surgery (Shuming Nie/David Kooby). Cancer immunotherapy chimera (Jacques Galipeau). Fine tuning old school chemo drug cisplatin (Paul Doetsch)
10. Tie between fructose effects on adolescent brain (Constance Harrell/Gretchen Neigh) and flu immunology (embrace the unfamiliar! Ali Ellebedy/Rafi Ahmed)
Posted on January 7, 2015 by Quinn Eastman in Uncategorized Leave a comment

Parkinson’s drug discovery: visit the dopamine container store

In a recent PNAS paper, Gary Miller and colleagues at Rollins School of Public Health outline a potential therapeutic approach to Parkinson’s disease that I’m going to call the Container Store approach.

If you have a mess in your kitchen or basement workshop, you might need more or better containers to hold your tools. Analogously, problems in Parkinson’s disease can be traced back to a lack of effective containers for the brain communication chemical dopamine.

Read more

Posted on June 18, 2014 by Quinn Eastman in Neuro Leave a comment

Eyes on dopamine

Dopamine-restoring drugs already used to treat Parkinson’s disease may also be beneficial for the treatment of diabetic retinopathy, a leading cause of blindness in adults, researchers have discovered. The results were published recently in Journal of Neuroscience.

Diabetic retinopathy affects more than a quarter of adults with diabetes and threatens the vision of more than 600,000 people in the United States. Doctors had previously thought most of the impairment of vision in diabetic retinopathy came from damage to the blood vessels induced by high blood sugar, but had known that dopamine, a vital neurotransmitter in the brain, was also important in the retina.

“There was some evidence already that dopamine levels were reduced in diabetic retinopathy, but what’s new here is: we can restore dopamine levels and improve visual Ray Ban outlet function in an animal model of diabetes,” says Machelle Pardue, PhD, associate professor of ophthalmology at Emory University School of Medicine and research career scientist at the Atlanta VA Medical Center. Read more

Posted on January 22, 2014 by Quinn Eastman in Neuro 1 Comment