Evaluation of laser induced sarcomere micro-damage: Role of damage extent and location in cardiomyocytes

PLoS One. 2021 Jun 4;16(6):e0252346. doi: 10.1371/journal.pone.0252346. eCollection 2021.

Abstract

Whereas it is evident that a well aligned and regular sarcomeric structure in cardiomyocytes is vital for heart function, considerably less is known about the contribution of individual elements to the mechanics of the entire cell. For instance, it is unclear whether altered Z-disc elements are the reason or the outcome of related cardiomyopathies. Therefore, it is crucial to gain more insight into this cellular organization. This study utilizes femtosecond laser-based nanosurgery to better understand sarcomeres and their repair upon damage. We investigated the influence of the extent and the location of the Z-disc damage. A single, three, five or ten Z-disc ablations were performed in neonatal rat cardiomyocytes. We employed image-based analysis using a self-written software together with different already published algorithms. We observed that cardiomyocyte survival associated with the damage extent, but not with the cell area or the total number of Z-discs per cell. The cell survival is independent of the damage position and can be compensated. However, the sarcomere alignment/orientation is changing over time after ablation. The contraction time is also independent of the extent of damage for the tested parameters. Additionally, we observed shortening rates between 6-7% of the initial sarcomere length in laser treated cardiomyocytes. This rate is an important indicator for force generation in myocytes. In conclusion, femtosecond laser-based nanosurgery together with image-based sarcomere tracking is a powerful tool to better understand the Z-disc complex and its force propagation function and role in cellular mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Animals
  • Cell Differentiation
  • Cells, Cultured
  • Image Processing, Computer-Assisted / methods
  • Lasers / adverse effects*
  • Myocardial Contraction / radiation effects
  • Myocytes, Cardiac / radiation effects*
  • Rats
  • Rats, Sprague-Dawley
  • Sarcomeres / radiation effects*

Grants and funding

This study was funded by the REBIRTH Research Center for Translational Regenerative Medicine (ZN3440, State of Lower Saxony, Ministry of Science and Culture (Nieders. Vorab)). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.