Nerve dependency in scarless fetal wound healing

Area of Science:

• Developmental Biology
• Regenerative Medicine
• Wound Healing Research

Background:

• Human fetuses can heal wounds without scarring until the third trimester.
• Fetal wound healing resembles newt limb regeneration, which depends on neural input.
• The role of neural input in mammalian scarless fetal wound healing is not well understood.

Purpose of the Study:

• To investigate if neural input is necessary for scarless mammalian fetal wound healing.
• To determine if denervation affects fetal wound repair processes.

Main Methods:

• Surgical denervation of the left hind limb in fetal lambs (day 55).
• Creation of incisional and excisional wounds on both denervated and innervated limbs.
• Examination of wound alterations, including contraction, healing, and scar formation, five days post-wounding.

Main Results:

• Denervated wounds showed impaired contraction and increased size compared to innervated wounds.
• Innervated wounds healed without scar, while denervated wounds exhibited delayed healing, dehiscence, or significant scarring.
• Electron microscopy revealed irregular collagen deposition in denervated wound tissues.

Conclusions:

• Neural stimulation is essential for scarless fetal skin wound repair in mammals.
• The primary regulator of this regenerative healing process may originate from the central nervous system.
• Findings suggest a critical role for the nervous system in promoting regenerative tissue repair.