An Environment to Thrive In: For Zebrafish Embryos and Me

By Helina Asrat, Summer Research Intern, Levin Lab

My name is Helina Asrat and I am a senior chemistry major at Berea College. After previous internships with the Berea College farm store where I focused on organic methods of pest management, and with a neuroscience lab, I have grown curious about how environmental pollutants affect the brain. To learn more about these issues, I am interning at the Superfund Research Center at Duke in Dr. Ed Levin’s lab this summer. Superfund research focuses on contaminated sites and pollutant exposures which may pose a risk to human health, as well as the environment. Dr. Levin examines the neurobehavioral effects to animal models such as zebrafish, killifish, rats, and C. elegans (small worms) that are exposed to environmental pollutants.

Helina hard at work in the lab

Polycyclic aromatic hydrocarbon (PAH) contamination is common at Superfund sites, and people are frequently exposed to these pollutants which can be found all around us. Sources of PAHs include industrial emissions from burning fuels, automotive exhaust fumes, cigarette smoke, agricultural sources like wood and biomass burning, pesticides, wood preservatives, water contamination from industries and oil spills, and even grilled foods. PAH exposures may contribute to birth defects, including effects on the nervous system. Research is still needed to develop methods that reduce the harm PAHs may cause to the developing brain.

The aim of this project is to use zebrafish embryos to study whether treatments, like the natural antioxidant Vitamin E, might prevent or limit the harmful effects of a widespread PAH, benzo-a-pyrene (BaP). When BaP breaks down, what’s left can easily bind to different cellular components, which disturbs the normal functioning of a cell, and can impact health. Vitamin E can prevent some of this cell binding, thus limiting cell damage. The lab is trying to determine if adding vitamin E to the water that zebrafish embryos live in will decrease the health effects of BaP exposure.

Zebrafish embryo exposed to 10μm BaP with curved spine or scoliosis (left) vs a healthy embryo exposed to vitamin E (right). Credit: Helina Asrat

I really like how neurobehavioral toxicity research goes full circle. It is not just about how people are exposed to a certain chemical and its effect on the body and brain at a biochemical level. The research also asks how we can test for behavioral effects caused by the exposure. The attempts to assess both toxicity and treatment mechanisms is fascinating, and really important for ultimately improving human health. The limited work on therapeutic treatments for environmental exposures make me wish projects like this one were more the norm. We should continually research possible solutions for existing effects of environmental pollutants, and implement actions that limit our exposure. Superfund research centers around the country are making strides in that direction, and I am glad to be a small part of it as an intern this summer.

I’m only now beginning to realize how much of a learning and growth opportunity this internship is for me. In addition to the vitamin E project, I am also learning a lot about neurobehavioral research more generally. This includes cognitive studies in rodents, how to work with zebrafish and rats, perform brain dissections, and use a data processing software, just to name a few.

Looking at how zebrafish embryos react to different environments under a microscope on a daily basis makes me realize how environmental pollution is also inevitably cellular and bodily pollution. This makes pollution a personal issue. This is why I think it is necessary that we collectively take action to understand and reduce environmental contamination and exposure effects, as well as develop ways to protect our health.

As an international student from Ethiopia, I had to venture into a new environment. This made me realize how important it is for me to seek and understand the microenvironments that I grow in, both in the lab and in everyday life. It feels really good to contribute to work that matters. But most importantly, I get to work with people who are willing to invest their time and energy to help me thrive now and in my future endeavors. I am grateful for this opportunity and I hope to learn and grow more in different ways as the internship progresses.