30 Going On 13: Researchers Renew Youthfulness in Adult Brains


Joanne Rhee
Staff Writer

It seems that every day we’re getting closer and closer to the fountain of youth—except this time it’s for our brains, not our appearances. Researchers at the University of California, Irvine have found a way to revert brains to their former, youthful stage.

Neurologist and assistant professor of neurobiology and behavior, Sunil Gandhi, and his colleagues have found a way to increase plasticity in the brain, which allows the brain to make new, quick connections. In a sense, it’s reverting the brain back to its younger self, making it more receptive to development.

Brain development is accelerated in the first three years of life. Young children learn to talk, walk, and throw tantrums, and the brain continues to develop and grow over the next 20 years. During this time, the brain remains pliable, allowing for new connections to be made. Learning and experience sculpt the brain during this important period of brain development.

Learning new instruments and picking up new languages isn’t as easy when you age. The brain slows down like the rest of the body. It loses plasticity and the ability to make quick, new connections through its receptors. Gandhi’s study transplants gamma-Aminobutyric acid (GABA) neurons and creates a new period of heightened plasticity that allowed vigorous rewiring of the adult brain. GABA is an important inhibitory transmitter that assists in vision, motor control, and other brain-related activities.

Research has been conducted on mice, who have very similar brains to humans. Scientists transplanted GABA neurons into the visual cortices of the brains of mice that suffered from amblyopia, which occurs during the normal development of vision and is characterized by partial or total loss of vision in one eye, commonly called “lazy eye.” This recreates what Gandhi calls the “juvenile critical period,” which is when the brain is most receptive to development.

“Several weeks after transplantation, when the donor animal’s visual system would be going through its critical period, the amblyopic mice started to see with normal visual acuity,” said Melissa Davis, lead researcher of the study.

Findings point to the use of GABA cell transplantation to enhance retraining of the adult brain after injury. Researchers have cleared the trail for further study that may lead to new treatments for developmental brain disorders, such as autism and schizophrenia. Furthermore, this work sparks new questions as to how GABA neurons reactivate plasticity.

“These experiments make clear that developmental mechanisms located within these GABA cells control the timing of the critical period,” said Gandhi.

Previous research on brain plasticity at Emory University led researchers to believe that progesterone, a steroid hormone that plays a role in menstruation and pregnancy in women, aided in brain damage recovery. Scientists found that female mice recovered faster than male mice, and attributed this to the hormone. However, further experiments involving placebos proved that progestin did not play a big role in acute brain injuries.

Dario Figueroa Velez, Roblen Guevarra, Michael Yang, Mariyam Habeeb, and Mathew Carathedathu of UCI contributed to the study, which was supported by a National Institutes of Health Director’s New Innovator Award, a Searle Scholars award, a Klingenstein Fellowship and a postdoctoral training grant from the California Institute for Regenerative Medicine.