As a 19-year-old education major, Rochelle Hines’ career ambition was to work with schoolchildren who have special needs. Then she enrolled in an elective course called “Brain and Behavior.”
“I was captivated,” Hines says. “By the second week of this class, I had changed my major and started working in the lab of my professor.”
The undergraduate research experience that followed enabled Hines to use various advanced technologies — electron microscopy among them — to gain a thrilling view of cerebral structures at the molecular level. From there, she went on to explore sites of communication between brain cells, called synapses, falling “in love with their incredible intricacy.
“I became focused on wanting to understand how we build billions of these complex structures so reliably during normal development, and how a failure in this process may lead to developmental disorders like those that I observed working with children with special needs.”
Her early fascination with neuroscience has spawned a career rich in research. Today, Rochelle Hines, along with her husband and collaborator, Dustin Hines, is rapidly expanding our understanding of how, for better or worse, neuronal activity patterns guide human behavior and ultimately contribute to pathology.
“Patterned activity in the brain is achieved through a balanced relationship between ‘on’ signals originating from excitatory cells and ‘off’ signals from inhibitory cells that act to modulate the activity of the excitatory cells,” she says. Her focus, she adds, tends toward the inhibitory cells, cellular “dimmer switches” that finely tune levels of excitation in the brain.
“Rochelle and I have a common thread, in that we both study cells in the brain that modulate brain activity patterns,” says Dustin, noting that he focuses more on the brain’s abundant glial cells, which surround neurons and provide support for and insulation between them.
Both professors in UNLV’s psychology department, they share an interest in this area of neuroscience for a number of reasons.
“The subject of modulatory cells has been attractive to us, as many studies are now pointing to this area as the most likely avenue for therapeutic advancement,” says Dustin, noting that pharmaceutical companies have been interested in his research. “We also enjoy working in these areas because, to date, they are largely under-studied in neuroscience. So it’s exciting to work on topics where there are a lot of new discoveries and advancements to be made.”
The two researchers, who met early in their careers, work synergistically. Both explore the functioning of these modulatory systems in the brain, but each has a specialty area. Rochelle uses a molecular and cellular approach to focus on interneurons, also called “relay neurons,” cells that modulate communication between other neurons. Dustin’s work with glial cells, specifically astrocytes and microglia, involves a cellular physiological and behavioral approach to understand how glia modulate neuronal communication.
His research has implications for degenerative maladies such as depression and stroke. For example, one of his studies examined how the chemicals activated in sleep deprivation may be used to help diminish depression. His research team used an animal model to examine how a certain compound that affects adenosine receptors in the brain mimics sleep deprivation and improves mood and behavior.
He believes glial cells have been largely overlooked in brain research and provide an oasis for novel therapeutics.
“The tools that were needed to study glial cells were not available early on in neuroscience research,” he says. “After World War II, many electrical technologies used to detect submarines, like oscilloscopes, drove the research; consequently, the electrical properties of neurons became the focus of the field. In the late 1980s, the development of new microscopes and genetic tools allowed us to see how glial cells contribute to brain function by modulating neurons.”
Rochelle’s research, meanwhile, examines how interneurons and inhibitory synapses affect neurodevelopmental disorders such as autism and schizophrenia. By investigating the activities of inhibitory cells in the brain — those “dimmer-switch” cells that finely tune levels of excitation — she seeks to learn more about the development of signaling in the nervous system.
“Excitatory signaling can be thought of as a typical light switch, either fully on or fully off,” she says, adding that inhibitory signaling modulates this activity, allowing for subtler variations of brain activity.
Like her husband, Rochelle chose to study a research area that has abundant potential for discovery.
“The role of inhibitory signaling is becoming increasingly apparent, and much of it is based on the symptoms associated with these disorders as well as studies in postmortem tissue from human subjects with these disorders,” she says.
She recently authored an article describing a study of inhibitory receptors in the brain and how certain inhibitory synapses might contribute to the symptoms of schizophrenia.
“These receptors are the target for many drugs that are in wide clinical use, including anesthetics and anti-anxiety and sleep drugs, so we know that they are a powerful target,” she says. Her work has also garnered the interest of pharmaceutical companies.
The couple has more than 50 scholarly journal articles between them. By the end of the year, they expect to submit their first jointly authored article emanating from their UNLV research. It will focus on how the brain regulates sleep.