Continuous NPWT Regulates Fibrosis in Murine Diabetic Wound Healing

Mengfan Wu; Dany Y Matar; Zhen Yu; Ziyu Chen; Samuel Knoedler; Brian Ng; Oliver A Darwish; Sadaf Sohrabi; Leigh Friedman; Valentin Haug; George F Murphy; Yuval Rinkevich; Dennis P Orgill; Adriana C Panayi

doi:10.3390/pharmaceutics14102125

Continuous NPWT Regulates Fibrosis in Murine Diabetic Wound Healing

Pharmaceutics. 2022 Oct 6;14(10):2125. doi: 10.3390/pharmaceutics14102125.

Authors

Mengfan Wu^{1

2}, Dany Y Matar^{2

3}, Zhen Yu^{4

5}, Ziyu Chen², Samuel Knoedler^{2

6}, Brian Ng^{2

7}, Oliver A Darwish^{2

8}, Sadaf Sohrabi⁹, Leigh Friedman^{2

10

11}, Valentin Haug^{2

12}, George F Murphy⁹, Yuval Rinkevich¹³, Dennis P Orgill², Adriana C Panayi^{2

12}

Affiliations

¹ Department of Plastic Surgery, Peking University Shenzhen Hospital, Shenzhen 518036, China.
² Division of Plastic Surgery, Department of Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
³ School of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA.
⁴ Shenzhen Key Ophthalmic Laboratory, Department of Ophthalmology, Shenzhen Eye Hospital, Jinan University, Shenzhen 518040, China.
⁵ Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
⁶ Department for Plastic Surgery and Hand Surgery, Klinikum Rechts der Isar, Technical University of Munich, 81675 Munich, Germany.
⁷ School of Medicine, Saint Louis University, St. Louis, MO 63104, USA.
⁸ School of Medicine, California Northstate University, Elk Grove, CA 95757, USA.
⁹ Division of Dermatopathology, Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
¹⁰ Department of Medicine, Lehigh University, Bethlehem, PA 18015, USA.
¹¹ School of Medicine, Drexel University, Philadelphia, PA 19129, USA.
¹² Department of Hand, Plastic and Reconstructive Surgery, Microsurgery, Burn Center, BG Trauma Center Ludwigshafen, University of Heidelberg, 67071 Ludwigshafen, Germany.
¹³ School of Medicine, Helmholtz Zentrum München, Institute of Regenerative Biology and Medicine, 81377 Munich, Germany.

Abstract

Scarring is associated with significant morbidity. The mechanical signaling factor yes-associated protein (YAP) has been linked to Engrailed-1 (En1)-lineage positive fibroblasts (EPFs), a pro-scarring fibroblast lineage, establishing a connection between mechanotransduction and fibrosis. In this study, we investigate the impact of micromechanical forces exerted through negative pressure wound therapy (NPWT) on the pathophysiology of fibrosis. Full-thickness excisional dorsal skin wounds were created on diabetic (db/db) mice which were treated with occlusive covering (control) or NPWT (continuous, −125 mmHg, 7 days; NPWT). Analysis was performed on tissue harvested 10 days after wounding. NPWT was associated with increased YAP (p = 0.04) but decreased En1 (p = 0.0001) and CD26 (p < 0.0001). The pro-fibrotic factors Vimentin (p = 0.04), α-SMA (p = 0.04) and HSP47 (p = 0.0008) were decreased with NPWT. Fibronectin was higher (p = 0.01) and collagen deposition lower in the NPWT group (p = 0.02). NPWT increased cellular proliferation (p = 0.002) and decreased apoptosis (p = 0.03). Western blotting demonstrated increased YAP (p = 0.02) and RhoA (p = 0.03) and decreased Caspase-3 (p = 0.03) with NPWT. NPWT uncouples YAP from EPF activation, through downregulation of Caspace-3, a pro-apoptotic factor linked to keloid formation. Mechanotransduction decreases multiple pro-fibrotic factors. Through this multifactorial process, NPWT significantly decreases fibrosis and offers promising potential as a mode to improve scar appearance.

Keywords: NPWT; YAP; caspase3; fibrosis; mechanotransduction; scarring; tissue regeneration; wound healing.

Abstract

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