Calcium signalling in wound-responsive normal human urothelial cell monolayers

Area of Science:

• Cell Biology
• Wound Healing Research
• Calcium Signaling

Background:

• Epithelial tissue repair necessitates coordinated cell migration and proliferation.
• The precise mechanisms of calcium signaling in this process remain largely unknown.
• Understanding calcium's role is crucial for elucidating tissue regeneration.

Purpose of the Study:

• To characterize the calcium signal in normal human urothelial (NHU) cells following scratch wounding.
• To correlate specific calcium signaling patterns with localized cellular responses.
• To identify key mediators involved in calcium wave propagation and sustained signaling.

Main Methods:

• Scratch wounding of confluent NHU cell monolayers.
• Measurement of intracellular calcium concentration ([Ca(2+)](i)) changes.
• Investigation of calcium release mechanisms, including involvement of intracellular stores, gap junctions, extracellular agonists, ATP, and inositol-1,4,5-triphosphate (IP(3)) receptors.

Main Results:

• A sustained rise in [Ca(2+)](i) (>30 min) was observed in cells adjacent to the wound edge.
• An independent, propagating calcium wave originated from the wound.
• ATP partially mediated the calcium wave, involving IP(3) receptor activation; sustained signals correlated with increased cell migration.

Conclusions:

• Distinct calcium signaling patterns (wave and sustained rise) are invoked by epithelial wounding.
• These calcium signatures, characterized by temporal and amplitude features, are vital for coordinating cellular responses.
• The findings provide evidence for calcium's role in epithelial repair and migration.