Potentially preventing pericyte contraction in low-oxygen environments

Pericytes are busy cells. Their responsibilities include sustaining the blood-brain barrier and regulating capillary blood flow by constricting and dilating. As such, their health is paramount for delivering nutrients and oxygen to brain tissue.

In some diseases like Alzheimer’s or in low-oxygen environments, pericytes needlessly contract, limiting blood flow. Islam et al. used a contraction cytometer to investigate pericyte behavior under these conditions.

“When a stroke is caused by a clot or obstruction, pericytes can become injured and die from the low-oxygen environment,” said author David Richard Myers. “The low-oxygen environment causes pericytes to constrict and remain constricted even after death. This is problematic because the dead pericyte will also be causing reduced blood flow through the vessel, potentially worsening tissue damage.”

Myers originally developed the contraction cytometer to investigate platelets but found it a useful instrument for studying pericyte constriction. The device consists of pairs of protein dots attached to a flexible substrate. When cells adhere to the dots and contract, the dots move in proportion to the applied force.

They confirmed that the pericytes were likely to experience injury or death in a low-oxygen environment, but their other results were more surprising.

“If pericytes were on a stiff surface, they could live longer, suggesting that somehow, the mechanical environment plays a role in modulating a pericyte’s survival in low-oxygen environments,” said Myers. “Although it is very preliminary, our work suggests that it may be possible to treat these dead pericytes and cause them to stop contracting.”

This platform may be helpful for screening treatments for pericytes injured by ischemic strokes or even preventatively reducing injury.

Source: “Single-pericyte nanomechanics measured by contraction cytometry,” by Md. Mydul Islam, Ignas Gaska, Oluwamayokun Oshinowo, Adiya Otumala, Shashank Shekhar, Nicholas Au Yong, and David R. Myers, APL Bioengineering (2024). The article can be accessed at https://doi.org/10.1063/5.0213761 .