The Yucatan miniature swine as a model for post-inflammatory hyperpigmentation

Area of Science:

• Dermatology
• Preclinical Research

Background:

• Post-inflammatory hyperpigmentation (PIH) is a common consequence of skin injury, particularly in darker skin tones.
• Effective treatment options for PIH are limited, and suitable preclinical models are scarce.

Purpose of the Study:

• To establish and validate the Yucatan miniature pig as a reliable preclinical model for studying post-inflammatory hyperpigmentation.
• To investigate the clinical and histological characteristics of PIH in this animal model.

Main Methods:

• Skin injuries (needle punches, excisions, burns) were inflicted on Yucatan miniature pigs.
• Wound sites were monitored, photographed, and tissue samples collected for histological analysis at 24 weeks.
• Computer-assisted image analysis quantified skin pigmentation and melanin content.

Main Results:

• All injury types induced significant hyperpigmentation in the pigs' skin.
• Histological analysis revealed increased epidermal and dermal melanin, with dermal deposits associated with leukocytes, not melanocytes.
• The model demonstrated persistent dermal melanin post-injury, mirroring human PIH.

Conclusions:

• The Yucatan miniature pig effectively models key features of human post-inflammatory hyperpigmentation.
• This model provides a valuable tool for understanding PIH etiology and developing novel therapeutic strategies.