Effect of topical insulin application on wound neutrophil function

Area of Science:

• Wound healing research
• Inflammation biology
• Dermatology and endocrinology

Background:

• Neutrophils play a critical role in wound inflammation and healing.
• Insulin's role in modulating the inflammatory response during wound healing is not fully understood.
• Understanding insulin's effects can lead to novel therapeutic strategies for wound management.

Purpose of the Study:

• To investigate the impact of topical insulin on wound neutrophil quantity and function.
• To elucidate the mechanism by which insulin influences the wound inflammatory response and promotes healing.
• To assess insulin's effect on key inflammatory markers and healing rates in excisional wounds.

Main Methods:

• Full-thickness excisional wounds were created in C57BL/6J mice.
• Wounds were treated with topical insulin or saline.
• Neutrophil infiltration, myeloperoxidase (MPO), malondialdehyde (MDA), and macrophage inflammatory protein-2 (MIP-2) expression were quantified using Western blotting, biochemical assays, and real-time PCR.

Main Results:

• Insulin treatment significantly reduced wound healing time and increased wound closure rates.
• Topical insulin suppressed neutrophil infiltration and MIP-2 expression within the initial two days post-injury.
• No significant differences in MPO or MDA levels were observed between insulin-treated and control groups.

Conclusions:

• Topical insulin accelerates wound healing by decreasing neutrophil infiltration via MIP-2 inhibition.
• Insulin demonstrates a regulatory role in the wound inflammatory process, promoting resolution.
• These findings suggest a potential therapeutic application of insulin in enhancing wound healing outcomes.