Eppur si muove: the dynamic brain pericyte

Area of Science:

• Neuroscience
• Cell Biology
• Physiology

Background:

• Brain pericytes, crucial for blood-brain barrier, neuroinflammation, cerebral blood flow (CBF), and angiogenesis, exhibit heterogeneity.
• Their roles in dynamic processes like contraction and migration are vital for brain function.

Purpose of the Study:

• To review the contractile elements of pericytes, focusing on alpha-smooth muscle actin (α-SMA) and myosin II.
• To discuss how pericyte subtypes generate mechanical forces for vascular regulation and remodeling.

Main Methods:

• Review of literature on pericyte contractile mechanisms.
• Analysis of α-SMA and myosin II isoforms (Myh11, Myh9) in pericyte function.
• Discussion of pericyte subtype roles in vasorelaxation, tone regulation, and ischemia.

Main Results:

• Distinct pericyte subtypes generate mechanical forces influencing vessel diameter and cellular processes.
• Ensheathing pericytes with high α-SMA mediate vasorelaxation during neurovascular coupling.
• α-SMA-low capillary pericytes regulate basal tone and respond to local stimuli, with differing roles in ischemic vasoconstriction.

Conclusions:

• Pericytes are dynamic cells exerting diverse mechanical forces crucial for physiological and pathological conditions.
• These findings underscore the multifaceted mechanical roles of pericytes in the brain.