Ointment vehicles regulate the wound-healing process by modifying the hyaluronan-rich matrix

Area of Science:

• Wound healing research
• Dermatology
• Biomaterials science

Background:

• Topical ointments are crucial for wound treatment, particularly for chronic wounds like pressure ulcers.
• Ointment vehicles, previously considered inert carriers, are now recognized for their distinct physicochemical properties and clinical effects.
• Understanding the mechanism of action of ointment vehicles in wound tissue is essential for optimizing treatment strategies.

Purpose of the Study:

• To investigate the tissue reactions induced by different ointment vehicles in a mouse wound model.
• To elucidate the role of ointment vehicles in regulating the wound microenvironment and extracellular matrix formation.
• To analyze the formation of specific complexes, such as the versican G1 fragment, serum-derived HA-associated protein (SHAP), and hyaluronan (HA) complex, in response to different vehicles.

Main Methods:

• Establishment of a mouse model for analyzing tissue reactions to oil-in-water emulsion (EM), macrogol ointment (MO), and macrogol ointment with sucrose (MS) vehicles.
• Histological analysis of tissue edema, granulation tissue, and inflammatory cell infiltration.
• Immunohistochemical and biochemical examination of water-holding extracellular matrix molecules, including hyaluronan (HA) and proteoglycans.

Main Results:

• EM-treated wounds showed significant inflammatory reactions, including edema and thick granulation tissue, with inflammatory cell infiltration.
• MO- and MS-treated wounds exhibited reduced inflammation and predominantly showed collagenous tissue formation.
• The HA-containing complex (VG1F-SHAP-HA), associated with inflammation in pressure ulcers, was found in EM-treated wounds but not in MO-treated wounds.

Conclusions:

• Ointment vehicles play a critical role in regulating wound healing processes by modulating tissue reactions and extracellular matrix composition.
• The water-holding capacity and physicochemical properties of vehicles influence the formation of hyaluronan-rich matrices at the ointment-wound interface.
• This study highlights the importance of selecting appropriate ointment vehicles for the effective treatment of deep-pressure ulcers.