For Dr. Aaron Polichnowski, the journey to the forefront of medical research began not in a laboratory, but on the baseball diamond at East Tennessee State University. The former Buccaneer athlete has since traded his spikes for a lab coat, returning to his alma mater to shape the next generation of physicians and tackle the complexities of renal disease at the Quillen College of Medicine.
Dr. Polichnowski, who earned his Bachelor of Science in Exercise Science from ETSU in 1999, was a member of the university’s baseball team during his undergraduate years. Today, his contributions to the university extend far beyond his athletic legacy. He was recently honored with the 2025 ETSU Distinguished Faculty Award, a testament to his excellence in both the classroom and the research wing. He serves as a primary instructor for cardiovascular and renal physiology, a role he believes is inseparable from his scientific inquiry.
“I think it makes me a better researcher,” Dr. Polichnowski said, “and being a researcher makes me a better teacher, too.”
His commitment to education is further evidenced by his role as the director of the summer medical school research program. By leading this initiative, he provides future doctors with the opportunity to understand the rigorous process of how research directly impacts medical practice. This mentorship ensures that the next wave of healthcare providers appreciates the scientific foundations of the treatments they will eventually prescribe.
According to Dr. Polichnowski, most developed countries consume salt at levels well above recommended limits, which carries a significant risk of stroke, myocardial infarction, and kidney disease. The importance of this research cannot be overstated for the Appalachian region and the United States, where high-sodium diets are a significant public health challenge.
With the American Heart Association recently lowering the threshold for hypertension to 130/80, roughly 50 percent of the U.S. population is now considered hypertensive, and about half of this group exhibits “salt-sensitive” hypertension, where blood pressure spikes further following a high-salt meal. Because the kidney is the dominant long-term regulator of blood pressure by regulating blood volume, his lab is focused on finding ways to protect the body from these dietary habits.
“It’s really hard to tell people to not eat salt,” he admitted. “Most people like a little salt in their food. So, I look at mechanisms that may help mitigate some of the effects of salt on blood pressure.”
The Polichnowski Lab is currently supported by three grants, allowing his team to spearhead investigations.
“I study renal hemodynamic mechanisms of acute and chronic kidney disease,” Dr. Polichnowski explained. “That encompasses a lot of diseases… acute kidney injury, chronic kidney disease, hypertension, obesity, diabetes. The mechanisms I look at certainly are applicable to all these.”
His team is exploring the molecular reasons behind high blood pressure, specifically the interplay between dietary salt and immune factors. By identifying how certain biological models fail to dilate their vasculature in response to salt, his lab hopes to develop therapies that target downstream pathways rather than relying solely on difficult-to-maintain dietary restrictions.
In a highly innovative move, Dr. Polichnowski’s team is also utilizing machine learning to develop algorithms that can accurately predict a patient’s susceptibility to chronic kidney disease based on raw blood pressure and renal blood flow data. This marriage of physiology and artificial intelligence represents a shift toward “precision medicine,” allowing for earlier and more accurate interventions.
Beyond salt and hypertension, Polichnowski is pivoting toward a modern environmental crisis involving polyfluorinated carbons, commonly known as “forever chemicals” or PFAS. These substances, found in nonstick cookware and water-resistant clothing, are notorious for contaminating waterways and remaining in the human body.
“Everybody has them in them,” Dr. Polichnowski said, referencing the legacy contamination that inspired the film “Dark Waters.”
A new two-year R21 grant is currently supporting research into the mechanisms by which these chemicals cause kidney injury and hypertension. By returning to the campus where he once competed as an athlete, Dr. Polichnowski has come full circle, leading a team that combines physiology, immunology, and machine learning to solve some of the most pressing health crises facing the local community and the nation.
Jargon Buster:
Renal Hemodynamics: The study of how blood flows through the kidneys and is needed for proper waste filtration and blood pressure maintenance.
Hypertension: High blood pressure.
Glomerular Filtration: The process the kidneys use to filter excess fluid and waste from blood.
