Cell wounding activates phospholipase D in primary mouse keratinocytes

Area of Science:

• Cell biology
• Biochemistry
• Dermatology

Background:

• Plasma membrane damage in mechanically active tissues like the epidermis can cause cell death if unrepaired.
• Membrane repair typically involves vesicle fusion to reseal disruptions.
• Phospholipase D (PLD) is known to be involved in membrane trafficking.

Purpose of the Study:

• To investigate the role of Phospholipase D (PLD) in cellular membrane repair.
• To identify the specific PLD isoform involved in membrane repair.
• To explore the therapeutic potential of PLD-mediated pathways in wound healing.

Main Methods:

• Induced plasma membrane disruptions in epidermal keratinocytes by cell lifting.
• Utilized PLD1 and PLD2 selective inhibitors to assess isoform involvement.
• Investigated the interaction between PLD2 and aquaporin-3 (AQP3) in phosphatidylglycerol (PG) production.
• Assessed membrane resealing in vitro using laser injury.
• Evaluated the effect of PG on wound healing in a mouse skin model.

Main Results:

• Cell lifting activated PLD, specifically the PLD2 isoform, while trypsinization did not.
• PLD2 inhibition impaired membrane resealing after laser-induced injury.
• Wounding led to decreased phosphatidylglycerol (PG) production, indicating a potential PG deficiency.
• Exogenous PG application accelerated wound healing in vivo.

Conclusions:

• The PLD2/AQP3 signaling module plays a critical role in epidermal membrane repair.
• PLD2 activation and subsequent PG production are essential for efficient membrane resealing.
• Targeting the PLD2/AQP3 pathway and PG levels shows promise for enhancing wound healing.