A Novel non-invasive optical framework for simultaneous analysis of contractility and calcium in single-cell cardiomyocytes.

The use of a video method based on the Digital Image Correlation (DIC) algorithm from experimental mechanics to estimate the displacements, strain field, and sarcolemma length in a beating single-cell cardiomyocyte is proposed in this work. The obtained deformation is then correlated with the calciu...

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Detalles Bibliográficos
Autores: Marimon X, Esquinas F, Ferrer M, Cerrolaza M, Portela A, Benítez R
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Fundació Sant Joan de Déu
Repositorio:r-FSJD. Repositorio Institucional de Producción Científica de la Fundació Sant Joan de Déu
OAI Identifier:oai:fsjd.fundanetsuite.com:p27209
Acceso en línea:https://fsjd.fundanetsuite.com/Publicaciones/ProdCientif/PublicacionFrw.aspx?id=27209
Access Level:acceso abierto
Palabra clave:Calcium imaging
Cardiomyocyte
Cellular biomechanics
Continuum mechanics
Digital image correlation
Image processing
Strain analysis
Descripción
Sumario:The use of a video method based on the Digital Image Correlation (DIC) algorithm from experimental mechanics to estimate the displacements, strain field, and sarcolemma length in a beating single-cell cardiomyocyte is proposed in this work. The obtained deformation is then correlated with the calcium signal, from calcium imaging where fluorescent dyes sensitive to calcium Ca(2+) are used. Our proposed video-based method for simultaneous contraction and intracellular calcium analysis results in a low-cost, non-invasive, and label-free method. This technique has shown great advantages in long-term observations because this type of intervention-free measurement neutralizes the possible alteration in the beating cardiomyocyte introduced by other techniques for measuring cell contractility (e.g., Traction Force Microscopy, Atomic Force Microscopy, Microfabrication or Optical tweezers). Three tests were performed with synthetically augmented data from cardiomyocyte images to validate the robustness of the algorithm. First, a simulated rigid translation of a referenced image is applied, then a rotation, and finally a controlled longitudinal deformation of the referenced image, thus simulating a native realistic deformation. Finally, the proposed framework is evaluated with real experimental data. To validate contraction induced by intracellular calcium concentration, this signal is correlated with a new deformation measure proposed in this article, which is independent of cell orientation in the imaging setup. Finally, based on the displacements obtained by the DIC algorithm, the change in sarcolemma length in a contracting cardiomyocyte is calculated and its temporal correlation with the calcium signal is obtained.