By 2022, UC Berkeley researcher Markita Landry thinks she will have developed the technology to X-ray brain tissue of live mice — a feat that would help doctors, scientists and pharmaceutical companies better understand the way antidepressants affect human brains.
It is an ambitious goal, but one that could help revolutionize the way drugs for depression, schizophrenia and other psychiatric disorders are studied and developed. The project received a five-year, $750,000 grant in February from the Biohub research initiative backed by Facebook founder Mark Zuckerberg and his wife, Dr. Priscilla Chan.
Landry, a biophysicist, and her team are building a microscope that can see in the infrared wavelength range, where tissue and bone are transparent. At the same time, they are developing a nanosensor that, when injected into the brain, will cause spots deep in the brain where dopamine is present to fluoresce. Dopamine is one of the major neurotransmitters — molecules in the brain that drive mood — that scientists and pharmaceutical companies target when developing drugs for psychiatric disorders.
Ironically, this technology of the future has been used to unlock secrets of the distant past: Art historians use a similar method to see through layers of paint to glimpse the original pencil sketches of artists from centuries ago.
Right now, Landry is studying slices of brain tissue from mice that can be preserved for seven hours after death. The tipping point, she says, will be when she can examine the brain tissue of mice while they’re still alive.
Doing so would represent a significant leap from current models for testing the efficacy of antidepressants, which involve dosing mice and rats with the drug and dropping them into a tank of water for a “forced swim test.” The vigor with which they swim indicates how well the drug is working.
Being able to track the way antidepressants affect human brain chemistry in real time — as opposed to relying on questionnaires and observations about patients who are taking antidepressants — would give researchers more insight into how the brain reacts to the drugs.
UC Berkeley has filed for a patent on the nanosensor, and Landry has spoken to some pharmaceutical firms that are interested in the technology because they are seeking better ways to test their antidepressants than swimming mice.
“What we need to do is demonstrate that we can measure dopamine in awake and behaving animals,” Landry said. “That will be the tipping point where this technology might provide a much better readout and more quantitative assessment of how antipsychotics and antidepressants work. Linking behavior to what happens in the brain will be really informative.”
Catherine Ho is a San Francisco Chronicle staff writer. Email: email@example.com Twitter: @Cat__Ho