After coming to USC with an MD from Beijing Medical University, Dr. Li Yang joined Dr. Alicia McDonough’s lab and chose to work on one of the most common, yet daunting problems in clinical medicine – blood pressure regulation, specifically how the kidneys adjust sodium transport: 1) when blood pressure is elevated, 2) when the kidneys are injured, and 3) in response to anti-hypertensive medication. Dr. Yang aimed to determine the molecular explanation for the natriuresis/diuresis that accompanies a rapid change in blood pressure. This response is critical to the setting and maintaining of baseline blood pressure and is altered in hypertension. She discovered that certain salt transporters were rapidly retracted out of the renal proximal tubule microvilli to a domain where they were unavailable for sodium transport during hypertension. Li Yang’s work has contributed significantly to the understanding of how the kidney senses and responds to hypertension and may identify candidate genes that contribute to the generation and maintenance of hypertension. This is a prerequisite to understanding the genesis of this disease. To accomplish these findings, Li also became an expert at confocal microscopy techniques as applied to the kidney. She studied and learned this method at the University of Indiana Division of Nephrology O’Brien Center and further explored applying techniques to whole animals with Dr. Janos Peti-Peterdi at USC. She was invited to present her work at “Experimental Biology 2000,” and her presentation was awarded the very competitive and prestigious Aventis Pharma Excellence in Renal Research Award from the American Physiologic Society.
Dr. Yang’s next project was in collaboration with Dr. Vito Campese, Chief of the Division of Nephrology and Hypertension at USC and concerned how an acute renal injury provokes chronic hypertension. Dr. Yang applied the cellular and biochemical analysis techniques she developed in her previous work to this question and conducted a proteomic analysis of how all the sodium transporters along the nephron were affected by renal injury. Her work established that acute injury activates sympathetic nervous system inputs to the kidney which provoke rapid redistribution of proximal tubule transporters to the apical cell surface along with increased salt and volume reabsorption and the generation of hypertension. Her research is the first study of this kind to prove that activation of the sympathetic nervous system moves sodium transporters to a location where they are more active in the kidney. She has presented her research findings at the ASN World Congress of Nephrology and EB 2002 where she received the Caroline tum Suden Career Development Award.
Dr. Li Yang received the John McKay Fellowship award in 2008, which allowed her to investigate various diets containing sodium and potassium and their effects upon blood pressure, renal disease, and metabolic syndrome. Read more about her fellowship research project.