Nearsightedness, also known as myopia, is one of the most common vision-related issues that people experience. The condition results when the light that shines through an eye focuses in front of the retina instead of on it, making faraway objects appear blurry. Research published in the paper “Biophysical properties of corneal cells reflect high myopia progression” in the August 17 issue of Biophysical Journal characterized corneal cells in eyes with myopia and found unique biophysical properties that could be related to nearsightedness.

By studying the corneal cells of young chicks, the researchers found that cells in the myopic condition had less F-actin and fewer microtubules than corneal cells without the condition. F-actin and microtubules are both abundant proteins that are important for cell movement and shape by interlinking to create the cytoskeleton. Various diseases can cause cells to remodel their cytoskeleton, which the results suggested could be the case for myopia as well. The lower levels of F-actin and microtubules revealed by immunofluorescence staining could mean that corneal cells in eyes with severe myopia also have a remodeled cytoskeleton.

If the cytoskeleton of a cell is remodeled, it could also affect the cell’s stiffness. Using atomic force microscopy, the authors observed that corneal cells in the myopic condition also appeared to be stiffer. Traction force microscopy experiments found that those cells had higher traction forces as well, which also affects the cells’ ability to move and maintain their structure.

In the study, the authors confirmed  that cytoskeleton remodeling in corneal cells is involved in myopia. They reported that once cells recovered to a healthy state, they had an amount of F-actin that was very similar to that in the control cells, which were cells from eyes that had not experienced any past myopia at all. Microtubules and cell stiffness appeared to partially recover back to the levels of the control cells, although not to the same levels. The recovered cells also had reduced cellular traction forces, resembling those in the control cells.

Diseased conditions can also result from dysregulated gene expression caused by processes such as irregular chromatin structures and condensation. The authors also found that cells in the myopic condition had more condensed chromatin, which was also restored to previous levels once the cells recovered to a healthy state.

A growing amount of research suggests that corneal tissues change when myopia progresses. By expanding the understanding of the relationship between cytoskeleton remodeling and nearsightedness, these biophysical changes could serve as an indicator or marker for myopia progression.