Sex differences in murine myocutaneous flap revascularization

Area of Science:

• Regenerative Medicine
• Vascular Biology
• Tissue Engineering

Background:

• Sex differences in ischemia/reperfusion injury are known in humans, particularly for heart disease.
• Premenopausal women have lower risk than men, but this changes post-menopause.
• Limited knowledge exists regarding sex-based effects on myocutaneous ischemia/reperfusion.

Purpose of the Study:

• To investigate sex differences in wound revascularization using a murine myocutaneous flap model.
• To analyze physiological, pathological, immunohistochemical, and molecular parameters in male and female mice.

Main Methods:

• Surgical creation of a cranial-based, peninsular-shaped myocutaneous flap in male and female mice.
• Assessment of flap viability, revascularization using laser speckle imaging, and vessel count via immunostaining.
• Analysis of gene expression related to growth factors and metabolism using RT-PCR.

Main Results:

• Female mice exhibited nearly complete flap viability at 10 days post-surgery.
• Male mice showed significant distal myocutaneous necrosis by day 10.
• Laser speckle imaging revealed functional revascularization in female flaps but minimal reperfusion in male flaps.
• Histology confirmed increased vessel count and surface area in female flaps.
• RT-PCR identified distinct gene expression patterns between sexes.

Conclusions:

• Flap revascularization is more effective in female mice in this graded ischemia model.
• Identifying sex-specific wound healing mechanisms can advance understanding of myocutaneous revascularization.
• This research may lead to improved soft tissue wound healing strategies for trauma and cancer resection patients.