The Role of Protein Loss and Denaturation in Determining Outcomes of Heating, Cryotherapy, and Irreversible Electroporation on Cardiomyocytes

This study was designed to help guide treatment thresholds and compare mechanism of action across heating, cryo, and IRE. Testing was undertaken on HL-1 cells, a well-established cardiomyocyte cell line, to assess injury thresholds for each treatment method. Cell viability, as assessed by Hoechst and propidium iodide (PI) staining, was found to be minimal after exposure to temperatures ≤−40 °C (cryo), ≥60 °C (heating), and when field strengths ≥1500 V/cm (IRE) were used. Viability was then correlated to protein denaturation fraction (PDF) as assessed by Fourier transform infrared (FTIR) spectroscopy, and protein loss fraction (PLF) as assessed by bicinchoninic acid ( BCA) assay after the three treatments. These protein changes were assessed both in the supernatant and the pellet of cell suspensions post-treatment. We found that dramatic viability loss (≥50%) correlated strongly with ≥12% protein change (PLF, PDF or a combination of the two) in every focal tr eatment. These studies help in defining both cellular thresholds and protein-based mechanisms of action that can be used to improve focal therapy application for AF.
Source: Journal of Biomechanical Engineering - Category: Biomedical Engineering Source Type: research