By Fatima Salinas
Two new faculty members in the Department of Biology in CLAS are advancing research on how the body develops and responds to disease, from the brain to the inner ear (cochlea) Cathy Yea Won Sung studies how immune cells contribute to hearing loss caused by certain medications that can affect hearing as a side effect, while Anne Martin examines how the brain forms early connections and their link to neurodevelopmental disorders.
Together, their work highlights the department’s growing focus on understanding complex biological systems and improving human health.
Cathy Yea Won Sung, a new faculty member in the College of Liberal Arts and Sciences Department of Biology, is studying how immune cells in the cochlea contribute to hearing loss caused by certain medications that are effective in treating diseases but can also have hearing-related side effects. One of the drugs she studies is cisplatin, a widely used anti-cancer drug treatment.
Sung was drawn to the University of Iowa for its environment for auditory research, with strong interdisciplinary connections across neuroscience, communication sciences, and medicine, along with its clinical trial infrastructure and support from the Holden Comprehensive Cancer Center.
“I was excited about the opportunity to be part of a collaborative environment that connects basic, translational, and clinical research,” Sung said, referring to Iowa’s network of labs and clinical programs that allow discoveries in the lab to move more efficiently toward patient care.
Before joining Iowa, Sung earned her undergraduate degree in microbiology at Iowa State University and completed her Ph.D. at the University of Alabama at Birmingham, where she studied how viral infections affect brain development and hearing. She later completed postdoctoral research at the National Institutes of Health, where she studied how immune cells in the body contribute to hearing loss caused by cisplatin. Cisplatin is a highly effective anti-cancer drug widely used in the clinic, but one of its side effects is permanent hearing loss.
Using an animal model, one of her major findings as a postdoctoral researcher was that Pexidartinib, a drug that removes macrophages (a type of immune cell), completely prevented cisplatin-induced hearing loss. This suggests that macrophages are important contributors to developing hearing loss following cisplatin treatment.
Sung now continues these studies in her independent laboratory at the University of Iowa to better understand how macrophages contribute to cisplatin-induced hearing loss.
“The immune cells act as gatekeepers, helping control how much of the drug gets into the inner ear,” she said.
The cochlea contains specialized macrophages called perivascular macrophages that sit around the blood barrier in the cochlea. Cisplatin is known to cross this barrier and enter the cochlea, where it can cause damage that leads to hearing loss.
One direction in her lab is to study whether these perivascular macrophages can regulate how much cisplatin enters the cochlea through this blood barrier. This is important because when cisplatin enters the cochlea and accumulates in cells essential for hearing, it can cause significant damage or even cell death, leading to permanent hearing loss.
“The perivascular macrophages act as gatekeepers, helping control what enters the cochlea from the blood, including how much of the drug gets into the cochlea,” she said.
Her previous research found that removing macrophages, including the perivascular macrophages, reduced the amount of cisplatin entering and accumulating in the cochlea, and these animals were fully protected from cisplatin-induced hearing loss and maintained normal hearing. These findings are promising and suggest a potential strategy to reduce hearing damage following cisplatin treatment.
Sung recently received funding from the National Institutes of Health to support this research.
Looking ahead, Sung hopes her research will lead to strategies that protect hearing in patients receiving chemotherapy without reducing treatment effectiveness.
“Cisplatin saves lives, but hearing loss can affect people long after treatment,” she said.
“We want to keep using cisplatin to effectively treat cancer patients while preserving the benefits of the drug.”
Anne Martin, studies how the brain forms its earliest connections and how those processes may relate to neurodevelopmental disorders.
Martin’s research focuses on neurodevelopment, specifically on how neurons decide to build and organize the connections that allow the brain to function. Her lab studies the molecular overlap between the two ways brain cells communicate. One uses chemicals (like dopamine and glutamate) to send messages, and the other connects cells directly so signals can move quickly.
Martin started her research career at the University of Georgia where she double majored in science and art. However, after gaining admission to a prestigious graphic design program, she focused on design, earned her degree, and worked in the design field for seven years before shifting to back to biology to study neuroscience. She later earned her Ph.D. in neurobiology and anatomy from the University of Utah and completed a postdoctoral fellowship at the University of Oregon. She joined the UI faculty in May 2025, where she runs her lab and teaches Neurobiology.
“It turns out having a background in design is very useful as a scientist. You are constantly needing to visually communicate your work and no one really teaches that to researchers,” she says. To mediate that, Martin has made part of her career providing that missing training to students as well as fellow colleagues.
Her work explores how neurons choose between building chemical or electrical synapses and how they manage shared molecular components.
“We’re really curious about how a neuron chooses to build a chemical synapse or an electrical synapse, and the molecular mechanisms used to drive that process,” Martin said.
These questions are important for understanding conditions such as epilepsy, autism, and intellectual disability, as these disorders are thought, in part, to be synaptopathies, or disorders of the synapse, and many of the proteins involved in synapse formation are found to be mutated in patients.
Martin recently received her first grant from the Roy J. Carver Charitable Trust to support her research. The funding will allow her lab to study the mechanisms used by a protein called Neurobeachin, which is necessary for both types of synapse formation, to orchestrate the formation of balanced connections across a neural circuit using larval zebrafish.
“It takes a weight off my shoulders knowing that I’ll be able to continue to support my growing lab and focus on the really cool science we’re doing,” she said. “The grant will also fund efforts to uncover new shared molecules between these two types of synapses, a fast-growing area of research that could transform how scientists understand brain development.”
Looking ahead, Martin hopes her work will help uncover the basic rules of how the brain wires itself and contributes to future therapies.
“Learning how the brain connects is fundamental biology that we don’t yet understand,” she said. “It is basic knowledge that is crucial for us to create targeted future therapies for patients with these disorders.”