Unraveling Nausea and Emesis Mechanisms through Hands-On Exploration

Allaha Mohiby, COL ’25, Pomona, NY

This summer, I had the opportunity to work in the lab of Professor DeJonghe. I had an amazing experience working alongside postdoctoral researcher Dr. Tito Borner and lab technician Allison Pataro. The lab focuses on understanding the neuronal mechanisms that mediate the side effects of nausea and emesis occurring as consequences of various treatments. Virtually all cancer patients experience emesis and nausea when receiving chemotherapy. Additionally, treatments for metabolic diseases, such as diabetes and obesity, are also characterized by severe nausea and emesis. These side effects have a negative impact on patients’ nutrition, quality of life, and treatment success. Nausea and emesis are controlled by the central nervous system, specifically by the area postrema and nucleus of the solitary tract, two nearby hindbrain structures. Despite scientific advances in the last decades, the underlying neuronal circuitry and its projections remain to be fully investigated.

During the summer, I studied the growth differentiation factor 15 (GDF15) and its involvement in nausea and emesis. GDF15 is a cytokine whose circulating levels significantly increase in conditions associated with nausea and emesis, including chemotherapy. Recent work from the lab discovered that GDF15 reduces food intake through nausea and emesis via the activation of hindbrain GFRAL receptors, which are exclusively expressed in the hindbrain. In some of the experiments I assisted with, a transgenic line (GFRAL-cre) was used in combination with site-specific viral (AAV) injections to selectively activate or inhibit GFRAL neurons and assess their role in the modulation of homeostatic and sickness behaviors.

The laboratory experience allowed me to assist with multiple in vivo pharmacological and behavioral studies in the context of nausea and emesis using various animal models and different paradigms of malaise. I had the opportunity to learn and master how to accurately measure food intake and kaolin consumption in rats (a proxy for nausea in rodents), various methods of drug administration (via intraperitoneal injection and gavage for oral delivery), and how to perform brain fixation, collection, and sectioning for further microscopy analysis. I also began learning the basics of microscopy and image processing. Importantly, I also learned how to critically read research papers at a level that would enable me to present them to the other members of the laboratory. My time management skills improved as maintenance tasks took less time the more I performed them. I also refined tasks such as data entry and statistical analysis.

I had worked in this lab in Spring 2023, but being in the lab all day during the summer allowed me to witness the complete process of experiments. Seeing the next step in the process helped me understand the importance of the previous step even more and gave each part of the experiment more purpose. I learned how to deal with issues along the way and prevent errors from arising. The experience has given me a newfound appreciation for research, and I look forward to conducting more research during my undergraduate years.

This is part of a series of posts by recipients of the 2023 Career Services Summer Funding Grant. We’ve asked funding recipients to reflect on their summer experiences and talk about the industries in which they spent their summer. You can read the entire series here.

By Career Services
Career Services