Scientists Enhance Technology for Brain Circuit Study
Scientists have bioengineered, in neurons cultured from rats, an enhancement to a cutting-edge technology that provides instant control over brain circuit activity with a flash of light.
Scientists have bioengineered, in neurons cultured from rats, an enhancement to a cutting-edge technology that provides instant control over brain circuit activity with a flash of light. The research, funded by NIH, adds the same level of control over turning neurons off that, until now, had been limited to turning them on.
“What had been working through a weak pump can now work through a highly responsive channel with many orders of magnitude more impact on cell function,” said Dr. Karl Deisseroth of Stanford University. It is like going from a squirt to a gushing hose.
Deisseroth and colleagues reported on what is being hailed as a marvel of genetic engineering in the Apr. 25 issue of the journal Science.
“This latest discovery by the Deisseroth team is the type of neurotechnology envisioned by President Obama when he launched the BRAIN Initiative a year ago,” said NIMH director Dr. Thomas Insel, whose institute helped fund the study, along with NIDA. “It creates a powerful tool that allows neuroscientists to apply a brake in any specific circuit with millisecond precision, beyond the power of any existing technology. This will be vital for understanding brain circuits involved in behavior, thinking and emotion.”
Muscle Weakness in Alcoholism Linked to Mitochondrial Repair Issues
Muscle weakness from long-term alcoholism may stem from an inability of mitochondria, the powerhouses of cells, to self-repair, according to a study funded by NIH.
In research conducted with rats, scientists found evidence that chronic heavy alcohol use affects a gene involved in mitochondrial repair and muscle regeneration.
“The finding gives insight into why chronic heavy drinking often saps muscle strength and it could also lead to new targets for medication development,” said NIAAA director Dr. George Koob, whose institute funded the study.
The study is available online in the April issue of the Journal of Cell Biology.
Glaucoma Drug Helps Women with Blinding Disorder Linked to Obesity
An inexpensive glaucoma drug, when added to a weight loss plan, can improve vision for women with a disorder called idiopathic intracranial hypertension (IIH), according to a study funded by NIH.
IIH, also called pseudotumor cerebri, predominantly affects overweight women of reproductive age. An estimated 100,000 Americans have it and the number is rising with the obesity epidemic. The most common symptoms are headaches and visual problems, including blind spots, poor side vision, double vision and temporary episodes of blindness. About 5-10 percent of women with IIH experience disabling vision loss.
“Our results show that acetazolamide can help preserve and actually restore vision for women with IIH, when combined with a moderate but comprehensive dietary and lifestyle modification plan,” said Dr. Michael Wall, professor of neurology and ophthalmology at the University of Iowa.
The trial was funded by NEI. The results were published Apr. 23 in the Journal of the American Medical Association.
Jump-Starting Natural Resilience Reverses Stress Susceptibility
Scientists have traced vulnerability to depression-like behaviors in mice to out-of-balance electrical activity inside neurons of the brain’s reward circuit and experimentally reversed it—but there’s a twist.
Instead of suppressing it, researchers funded by NIH boosted runaway neuronal activity even further, eventually triggering a compensatory self-stabilizing response. Once electrical balance was restored, previously susceptible animals were no longer prone to becoming withdrawn, anxious and listless following socially stressful experiences.
“To our surprise, neurons in this circuit harbor their own self-tuning, homeostatic mechanism of natural resilience,” said NIMH grantee Dr. Ming-Hu Han of Icahn School of Medicine at Mount Sinai, New York City.
Han and colleagues reported on their discovery Apr. 18 in the journal Science.