A small molecule HIF-1α stabilizer that accelerates diabetic wound healing

Area of Science:

• Biochemistry
• Medicinal Chemistry
• Regenerative Medicine

Background:

• Diabetic patients suffer from impaired wound healing and ulcer complications.
• Hypoxia-inducible factor-1α (HIF-1α) plays a critical role in cellular response to hypoxia and wound repair.
• The Von Hippel-Lindau (VHL) protein targets HIF-1α for degradation, limiting its therapeutic potential.

Purpose of the Study:

• To design and synthesize a novel cyclometalated iridium(III) complex as a stabilizer of HIF-1α.
• To investigate the mechanism of action of the iridium(III) complex in vitro and in vivo.
• To evaluate the therapeutic efficacy of the compound for accelerating wound healing, particularly in diabetic models.

Main Methods:

• Synthesis and characterization of a cyclometalated iridium(III) complex (1a).
• In vitro biophysical and cellular assays to assess VHL binding and HIF-1α stabilization.
• Analysis of HIF-1α mediated gene expression (VEGF, GLUT1, EPO).
• In vivo studies using normal and diabetic mouse models (db/db, HFD/STZ, STZ) to evaluate wound closure and gene expression in wound tissue.

Main Results:

• The iridium(III) complex 1a binds to VHL, inhibiting the VHL-HIF-1α interaction.
• Compound 1a effectively accumulates HIF-1α levels in cells and activates HIF-1α target genes.
• In vivo, compound 1a significantly accelerated wound closure in both normal and diabetic mice, with enhanced efficacy in diabetic models.
• Treatment with 1a increased the expression of HIF-1α-driven wound healing genes in diabetic mouse wound tissues.

Conclusions:

• A small molecule stabilizer of HIF-1α, the iridium(III) complex 1a, shows promise as a therapeutic agent for wound healing.
• Blocking the VHL and HIF-1α interaction is a validated strategy for treating diabetic wounds.
• This approach offers a potential new avenue for managing complications associated with diabetes.