024 - Investigating the role of Perilipin-2 in successful repair of the renal proximal tubule following ischemia-reperfusion injury
Sunday, April 27, 2025
8:30am – 10:45am HST
Publication Number: 24.5792
Matthew J. Biehl, Washington University in St. Louis School of Medicine, St. Louis, MO, United States; Haikuo Li, Yale University, New Haven, CT, United States; Benjamin Humphreys, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
Clinical fellow Washington University in St. Louis School of Medicine St. Louis, Missouri, United States
Background: Acute kidney injury (AKI) is a commonly observed phenomenon in hospitalized patents and is defined as either a decrease in urine output or marked increase in serum creatinine compared to either baseline values or to expected values based on age and size. A breadth of literature has demonstrated that repeated injury can contribute to the AKI-to-chronic kidney disease (CKD) transition, and that inherent repair mechanisms exist to overcome this perpetuation. The proximal tubule of the kidney is of particular interest, as it is a highly metabolically active and is especially prone to stressors such as filtered toxic metabolites and hypoxia. Objective: Previous data from our lab has suggested that the lipid-droplet coating protein perilipin-2 (PLIN2) is strongly upregulated in mouse kidneys following ischemia reperfusion injury (IRI) or in human renal primary proximal tubule cells (RPTECs) co-treated with fatty acid. Upregulation of Plin2 mRNA coincided with alterations in oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) in RPTECs and would suggest that PLIN2 plays a critical role in energy homeostasis and repair following hypoxic injury. Currently, our goal is to understand the molecular mechanisms which PLIN2 mediates to promote successful repair. Design/Methods: In vivo studies utilized Plin2 fl/fl mice to manipulate Plin2 expression via cre-lox technology. Mice of this background were also used for rhabdomyolysis studies. Cultured mouse RPTECs were harvested from adult Plin2 fl/fl mice (males and females), and Plin2 expression was manipulated via transduction with Adenovirus-cre or fatty acid treatment. Human RPTECs were cultured from donors of different disease states, and Plin2 expression was manipulated via transfection with siRNA or with fatty acid treatment Results: Preliminarily, we have shown and upregulation of PLIN2 in the proximal tubule (PT) appears to be unique to IRI in vivo. In vitro, we have demonstrated the ability to culture primary RPTECs from both mouse and human kidneys, and that both models are able to have Plin2 expression manipulated at a protein and mRNA level.
Conclusion(s): These data have established multiple in vivo and in vitro models to explore the functional role of PLIN2 in the recovering kidney. We are hopeful these in vitro assays will serve as useful to perform functional and mechanistic studies, and that we will be able to knock out Plin2 in a select population of cells in the kidney utilizing cre-lox technology to further elucidate its role in vivo.
