Mechanistic study of Small-molecular Therapy in diabetic Wound Healing

Diabetic foot ulcers that lead to amputations are a major health problem affecting ~20% of the 30 million diabetic patients in the US. The current regimen has limited success, and the amputation rates remain high.

Therefore, understanding molecular mechanisms for compounds with translational potential is a crucial step toward making a breakthrough in wound care protocols. Endothelial cells (ECs) are indispensable cellular components for wound angiogenesis. However, EC functions are impaired in patients with diabetes.

The coformulation of two dietary compounds - Trans-resveratrol (tRES) and hesperetin (HESP) - improves glucose metabolic profile and arterial function in overweight and obese subjects through inducing the gene expression of glyoxalase 1 (GLO1), an enzyme that detoxifies reactive metabolites during glycolysis and protects cells against glycation stress.

Our pilot data indicated that tRES+HESP improved wound healing in diabetic animals with an increase in GLO1 expression.

However, its effects are likely far beyond inducing GLO1 expression because tRES+HESP treated ECs produced many pro-angiogenic factors, including angiopoietin-1 (ANGPT1) that plays an essential role in angiogenesis. Therefore, it is critical to determine proteins that are regulated by tRES+HESP in angiogenesis and tissue repair.

The objective of this project is to fill the knowledge gap of the role of tRES+HESP in rescuing the disrupted angiogenesis in diabetes, and our long-term goal is to develop therapeutic strategies for diabetic wound repair.

We hypothesize that tRES+HESP augments angiogenesis and improves diabetic wound healing through enhancing the expression of GLO1 and a potent pro-angiogenic factor, ANGPT1, and through novel changes in additional proteins in pathways critical to diabetic wound repair.

Aim 1: Identification of molecular pathways and protein changes induced by tRES+HESP in human dermal microvascular ECs in vitro. Sub-aim 1: Determine to what extent tRES+HESP can rescue diabetic endothelial cell function in vitro. Sub-aim 2: Determine how vital ANGPT1 is in tRES+HESP-induced angiogenesis in vitro.

Sub-aim 3: Discover new proteins and pathways responsible for the benefit of tRES+HESP treatment in endothelial cell function in vitro using state- of-the-art proteomics.

Aim 2: Determine the therapeutic potential of tRES+HESP and its underlying molecular mechanisms in chronic diabetic wounds in vivo.

Sub-aim 1: Determine the efficacy of tRES+HESP on wound healing in a newly developed diabetic chronic wound model in db/db mice. Sub-aim 2: Determine the role of ANGPT1 in the tRES+HESP-induced improvement in wound healing in vivo.

Sub-aim 3: Discover new proteins and pathways responsible for the benefit of tRES+HESP treatment in diabetic wound repair in vivo using state- of-the-art proteomics.

The outcome of the proposed research will determine the efficacy of topical application of this formula, tRES+HESP, in diabetic wound healing, and will unveil underlying molecular mechanisms for its beneficial effect.

Since tRES+HESP has not been approved by the FDA to treat diabetic wound healing yet, these results may facilitate the FDA approval of this coformulation in diabetic wound treatment.