Before the cardiologist goes nuclear w/ stress #AHA17

Measuring troponin in CAD patients before embarking on stress testing may provide Read more

Virus hunting season open

Previously unknown viruses, identified by Winship + UCSF scientists, come from a patient with a melanoma that had metastasized to the Read more

#AHA17 highlight: cardiac pacemaker cells

Highlighting new research on engineering induced pacemaker cells from Hee Cheol Cho's Read more

parathyroid hormone

Immune studies suggest remedies for parathyroid hormone-driven bone loss

A common cause of bone loss is an overactive parathyroid gland, which doctors usually treat with surgery. New research on how excess parathyroid hormone affects immune cells suggests that doctors could repurpose existing drugs to treat hyperparathyroidism without surgery.

The results were published October 8 in Cell Metabolism. [My apologies for not posting this in October.]

“Surgery is sometimes not an appropriate remedy for hyperparathyroidism because of the condition of the patient, and it is also expensive,” says lead author Roberto Pacifici, MD. “Also, the one pharmacological treatment that is available, cinacalcet, is not always the ideal solution. This work could potentially lead to alternatives.”

Roberto Pacifici, MD

Researchers at Emory University School of Medicine led by Pacifici teamed up with doctors from the University of Turin in Italy, combining observations of human patients with an overactive parathyroid with experiments on mice.

The drugs identified as potential treatments are: calcium channel blockers, now used to treat high blood pressure, and antibodies that block the inflammatory molecule IL-17A, under development for the skin disease psoriasis. Clinical trials would be necessary to show that these drugs are effective against parathyroid hormone-induced bone loss in humans. Read more

Posted on by Quinn Eastman in Immunology Leave a comment

Everything in moderation, especially TH17 cells

I was struck by one part of Mirko Paiardini’s paper that was published this week in Journal of Clinical Investigation. It describes a treatment aimed at repairing immune function in SIV-infected monkeys, with an eye toward helping people with HIV one day. One of the goals of their IL-21 treatment is to restore intestinal Th17 cells, which are depleted by viral infection. In this context, IL-21’s effect is anti-inflammatory.

However, Th17 cells are also involved in autoimmune disease. A recent Cell Metabolism paper from endocrinologist Roberto Pacifici and colleagues examines Th17 cells, with the goal of treating bone loss coming from an overactive parathyroid. In that situation, too many Th17 cells are bad and they need to be beaten back. Fortunately, both an inexpensive blood pressure medication and a drug under development for psoriasis seem to do just that.

Note for microbiome fans: connections between Th17 cells and intestinal microbes (segmented filamentous bacteria) are strengthening. It gets complicated because gut microbiota, together with Th17 cells, may influence metabolic disease and Th17-like cells are also in the skin — location matters.

Posted on by Quinn Eastman in Immunology 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. Threepart 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 by Quinn Eastman in Uncategorized Leave a comment

PTH for stroke: stem cells lite

I’d like to highlight a paper in PLOS One from anesthesiologists Shan Ping Yu and Ling Wei’s group that was published earlier this year. [Sorry for missing it then!] They are investigating potential therapies for stroke, long a frustrating area of clinical research. The “clot-busting” drug tPA remains the only FDA-approved therapy, despite decades of work on potential neuroprotective agents.

Yu’s team takes a different tactic. They seek to bolster the brain’s recovery powers after stroke by mobilizing endogenous progenitor cells. I will call this approach “stem cells lite.”

journal.pone.0087284.g006

PTH appears to encourage new neurons in recovery in a mouse model of ischemic stroke. Green = recent cell division, red = neuronal marker

It is similar to that taken by cardiologist Arshed Quyyumi and colleagues with peripheral artery disease: use a growth factor (GM-CSF), which is usually employed for another purpose, to get the body’s own regenerative agents to emerge from the bone marrow.

In this case, Yu’s team was using parathyroid hormone (PTH), which is an FDA-approved treatment for osteoporosis. They administered it, beginning one hour after loss of blood flow, in a mouse model of ischemic stroke. They found that daily treatment with PTH spurs production of endogenous regenerative factors in the stroke-affected area of the brain. They observed both increased new neuron formation and sensorimotor functional recovery. However, PTH does not pass through the blood-brain barrier and does not change the size of the stroke-affected area, the researchers found.

The conclusion of the paper hints at their next steps:

As this is the first report on this PTH therapy for ischemic stroke for the demonstration of the efficacy and feasibility, PTH treatment was initiated at 1 hr after stroke followed by repeated administrations for 6 days. We expect that even more delayed treatment of PTH, e.g. several hrs after stroke, can be beneficial in promoting chronic angiogenesis and other tissue repair processes. This possibility, however, remains to be further evaluated in a more translational investigation.

Posted on by Quinn Eastman in Neuro 1 Comment