# Regulatory Mechanisms Addressing Diabetic Vasculopathy

> **NIH NIH R01** · UNIVERSITY OF PITTSBURGH AT PITTSBURGH · 2024 · $367,157

## Abstract

ABSTRACT
The prevalence of diabetes, obesity, and vascular disease in an aging population is fueling a surge in chronic
skin wounds, which affect >8 million Medicare beneficiaries at a cost of >$96 billion per year. An estimated 2.5%
of US population is affected by chronic wounds. Diabetic ulcers (DU), complicated by infection/ischemia/high
reactive oxygen species, often suffer from poor perfusion. Reliance on VEGF therapy to improve perfusion
makes logical sense, yet clinical study outcomes fall far short of expectations. Possible factors limiting VEGF
therapy outcomes include insufficient local concentration of VEGF signaling partners and regression of immature
vessels. It is critically important to troubleshoot barriers and to establish a therapeutic regimen that delivers
desirable functional outcomes. To circumvent the low-efficiency hurdle of VEGF single-gene “monotherapy”,
development of “combined gene therapy” was initiated to deliver of two or more angiogenic molecules to
substantially enhance efficacy. Current literature presents compelling evidence recognizing a critical role of
active lipid mediators such as eicosanoids in enabling VEGF-dependent angiogenesis. However, the
implementation of VEGF therapy has not tested the significance of these lipid mediators as necessary adjuvant.
Recently we have reported that in diabetic ischemic skin endothelial cells, PLCγ2 levels remain low accounting
for diminished efficiency of VEGF therapy. However, the underlying mechanisms of such downregulation remain
unknown. Emerging evidence demonstrate that hyperglycemia leads to DNA methylation and epigenetic
silencing in the complex interplay between genes and the environment in DU subjects. In addition to endothelium,
PLCγ2 enables macrophage function via TREM2 signaling. TREM2+ macrophages participate in tissue
angiogenesis post-injury. The central hypothesis is that hyperglycemia dependent loss of vascular PLCγ2–
myeloid TREM2 crosstalk compromises VEGF-induced increase in diabetic wound-edge vascularization. Gene
targeted DNA demethylation has potential to rescue PLCγ2 gene expression. The proposed line of work is the
first to study CRISPR/dCas9-based in vivo targeted epigenetic editing of dermal endothelial cells as a therapeutic
intervention for enabling VEGF therapy. Three aims are proposed: Aim 1. Determine the epigenetic mechanisms
underlying PLCγ2 regulation of VEGF signaling under hyperglycemic conditions. Aim 2. Elucidate the molecular
mechanisms by which PLCγ2 regulates wound tissue vascularization. Aim 3. Evaluate the functional significance
of endothelial-targeted PLCγ2 augmentation in vascular-myeloid crosstalk as it relates to diabetic wound
vascularization. The proposed research will unveil the critical role of PLCγ2 and the impact of this important
element in VEGF signaling to help improve the efficiency and robustness of vasculogenic VEGF therapy in
diabetic wound healing.

## Key facts

- **NIH application ID:** 10900604
- **Project number:** 5R01DK136814-02
- **Recipient organization:** UNIVERSITY OF PITTSBURGH AT PITTSBURGH
- **Principal Investigator:** Kanhaiya Singh
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $367,157
- **Award type:** 5
- **Project period:** 2023-08-07 → 2028-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10900604

## Citation

> US National Institutes of Health, RePORTER application 10900604, Regulatory Mechanisms Addressing Diabetic Vasculopathy (5R01DK136814-02). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10900604. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*