Las células se ‘ablandan y fluidizan’ ante estímulos con altas frecuencias. / ICMM

Characterizing the mechanical behavior of a mammalian cell to better treat it when it is sick, or to prevent it from becoming ill. This is what a research team from the Institute of Materials Science of Madrid (ICMM-CSIC) has done, which has just discovered how cells have a different response when subjected to high or low frequency. This study, published in the journal Small, is an essential step for the advancement of nanomedicine in diseases such as spinal cord injuries.

"In physiology and medicine, they aim to develop nanomechanical markers at the cellular level, which is the smallest biological unit," explains Ricardo García, a researcher at ICMM-CSIC and the study's lead author. "But to know which marker to use, you need to understand which elements of the cell react when you interact with it."

Therefore, the work has used atomic force microscopy technology (which has the ability to study elements at the smallest level, the atom) and has observed how when a force is applied to a cell at a low frequency (1 hertz), its response is dominated by its solid elements - the membrane and cortex. However, when this force is applied at a high frequency of 100 hertz, the mechanical response of the cell is dominated by liquid elements, the cytosol.

In addition, this team has observed that this 'softening and fluidization' of cells in response to high-frequency stimuli does not seem to indicate any change in their structure: "A physical process occurs between solid and liquid elements, but it does not necessarily have to be related to the health of that cell," clarifies García.

The study is part of the Piezo4Spine project, which aims to cure spinal cord injuries and is coordinated by ICMM-CSIC researcher Conchi Serrano and funded by the European Union. Now, knowing that the solid elements of cells are more related to the development of diseases, and that these solid elements dominate the cell's response to interactions at low frequencies, this working team will be able to focus the development of nanomechanical markers much more precisely.

"These findings provide the most fundamental description of the mechanical response of a mammalian cell based on the frequency or speed of deformation," concludes García, adding that any mechanobiological analysis of a cell based on mechanical stimulus "must explicitly consider the interaction between the solid and liquid components of the cell." 

Scientific Reference:
Victor G. Gisbert, Francisco M. Espinosa, Juan G. Sanchez, Maria Concepcion Serrano, Ricardo Garcia: Nanorheology and Nanoindentation Revealed a Softening and an Increased Viscous Fluidity of Adherent Mammalian Cells upon Increasing the Frequency. Small. DOI: 10.1002/smll.202304884

Wednesday, November 22, 2023 - 12:32