Searching for solutions to the impacts of climate change on human health

Chuan He, PhD, is the first director of the Pritzker Plant Biology Center at UChicago, housed in the greenhouse atop the Biological Sciences Learning Center
Chuan He, PhD, is the first director of the Pritzker Plant Biology Center at UChicago, housed in the greenhouse atop the Biological Sciences Learning Center.
The links between climate change and human health are becoming increasingly obvious: Pollution. Extreme weather events. Food scarcity. Pathogen spread.

Meet the University of Chicago researchers who are tackling this monumental issue, one challenge at a time.

New plants for a new world: targeting food insecurity with plant biology

Achieving tenure as a Professor of Chemistry at the University of Chicago gave Chuan He, PhD, the freedom to start something new. “I decided to not just be a chemist,” he said. “And I started to think about what I could work on, and landed on RNA modifications. When we started in this field there was very little research in this arena at the time, but recently the field has exploded, because it turns out to be vital to all kinds of biological processes.”

In 2021, He and collaborators published a groundbreaking study showing that by inserting the FTO gene, which affects RNA modification, into rice, the plants grew three times more rice in the lab — and 50% more rice in the field. The rice plants also grew longer roots, were better able to withstand stress from drought, and photosynthesized more efficiently. Additional experiments in potato plants yielded similar results.

Now He is the director of the Pritzker Plant Biology Center, a new space to expand his RNA modification work and the research of other scientists searching for innovative ways to promote plant growth and resilience and increase crop yield.

“We’re considering many layers of pathways for modulating plant growth,” he said. “RNA modification is one aspect, but we’re also looking at temperature sensing, because agriculture may have to move north as the climate warms, but northern regions will still be hit by extreme cold fronts, so we’ll need to develop plants that can resist the cold and grow fast. We also need crop plants that can better withstand warm weather. We could even modulate photosynthesis to increase biomass and yield.

“In the last several decades we’ve seen a huge amount of resources being put into human biology and health, and rightfully so,” He said. “But until now we have not paid enough attention to plant biology, and with climate change, this type of research is just as important.”

‘An existential issue’: wealth, race and health inequities exacerbated by climate change

Elizabeth Tung, PhD, works in the urgent care clinic at UChicago Medicine’s Hyde Park campus, providing care for members of the South Side community.
Elizabeth Tung, PhD, works in the urgent care clinic at UChicago Medicine’s Hyde Park campus, providing care for members of the South Side community.
Elizabeth Tung, MD, Assistant Professor of Medicine, focuses her research primarily on how race and wealth contribute to health inequities. The line to climate change may not be immediately obvious, but the relationship is there. She points to a recent lettuce shortage: “Lettuce got more expensive because of issues related to climate change,” she said. “As the climate changes, who will be able to afford nutritious food, and what does that mean for the health of our communities? There’s a real connection there.”

She studies health disparities caused by social inequity, and wonders how they can be exacerbated by the pressures of climate change. “We know that people with lower income, who are experiencing racism or violence, have much higher allostatic load than those who are not facing the same stressors,” she said. “That chronic activation of stress responses can increase stress hormones like cortisol, and over time that can directly impact health. Chronic stress contributes to a host of health problems, including cardiovascular disease, which is the largest contributor to the racial mortality gap.”

Climate change is yet another source of inequity; those with the fewest resources and who are the most vulnerable are disproportionately affected by it, in everything from the rising cost of food to a lack of secure shelter from extreme weather events to increased risk of exposure to pollution and infectious disease.

An area of particular focus for Tung is the intersection between violence and health inequity. “Violence is an outcome of inequity,” she said. “More than medical and mental healthcare, patients who are affected by violent injury will often say they need access to economic and legal resources. For example, eviction can be equally or more toxic to a person than not being able to fully rehab an injured leg. The chronicity of stress related to housing instability has major downstream effects on people’s lives and wellbeing.” Add to that the effects of climate change on housing, which have already exacerbated the affordable housing crisis and increased housing damage due to flooding and other natural disasters.

These climate challenges will not only exacerbate existing health inequities, but will increase the strain on an already struggling healthcare system, making it ever more difficult for those most burdened by the effects of climate change to access the resources they need to survive it. The question isn’t so much whether these issues will get worse in the future, but rather, how to address it.

“There’s a big movement in the health sciences to place a greater emphasis on the social determinants of health, but this is an existential issue,” said Tung. “Most of the solutions currently available to us rely on addressing the specific needs of an individual person or patient, but they don’t provide opportunities for systemic change. If wealth inequality continues to worsen, it will become even more difficult to sustain the services that we are able to offer. It’s a never-ending cycle.”

How our environment affects us: environmental exposures are changing our genes

Yu-Ying He, PhD, studies how environmental exposures change our RNA, and how those changes may increase the risk of cancer.
Yu-Ying He, PhD, studies how environmental exposures change our RNA, and how those changes may increase the risk of cancer.
When she arrived in Beijing as a new university student, Yu-Ying He, PhD, was struck by the contrast to the rural area where she grew up — and especially the amount of pollution in the air, a major issue during that time.

“It constantly made me think about how different environments can lead to differences in our health, even when we’re working with a very similar genome,” she said. “It made me wonder how the biology works when we’re exposed to certain chemicals or radiation or even biological factors, like a virus. These things can put an imprint on our bodies, but we don’t always know what the long-term effects will be.”

Her current research focus is on understanding how exposure to UVB radiation and arsenic affect the role of RNA methylation in cancer development. She studies epitranscriptomics — the modifications made to RNA that affect how and which proteins are produced within our cells.

She sees a connection between her work and climate change because it all comes back to one thing: human decisions. “Climate change and pollution are deeply connected,” He said. “The chemicals we make and release into the atmosphere are a huge contributor to climate change. Humans are very innovative. However, we humans also create these unexpected and unintended consequences, but because it takes years for the toxic response to appear, we don’t realize it right away.

Perhaps the most obvious connection between her work and climate change is one that has been mostly successfully addressed by policy change. Those who grew up in the 1990s likely remember learning about the “hole in the ozone layer,” caused by human use of chemicals such as chlorofluorocarbons. Ozone layer depletion allows more UVB rays to reach the planet’s surface, affecting everything from agriculture to marine ecosystems to cancer rates in humans. Thanks to international agreements reducing the use of chlorofluorocarbons in the 1980s, the ozone hole is slowly shrinking; but in the meantime, its effects still remain.

One of the challenges He faces is determining which RNA changes are significant. “We’ve seen RNA modifications in response to UV stress a few times, but we don’t really know what the implication of that is,” she said. “There are classical responses, such as DNA damage, but epitranscriptomics is still in its infantry. We are probably one of the few groups looking at the unique connection between epitranscriptomics and the environment, which is helping us understand how dysfunction in the machinery caused by environmental exposures contributes to diseases.”