Carbon Dots Induce Epithelial‐Mesenchymal Transition for Promoting Cutaneous Wound Healing via Activation of TGF‐β/p38/Snail Pathway

Abstract

Skin lesions, as a relatively common clinical manifestation, not only damage the skin's barrier function, but also affect the skin's ability to feel temperature, pain and touch. However, a highly efficient method to restore the morphology and function of damaged skin remains an unmet goal. In this work, carbon dots (CDots) with excellent biocompatibility are synthesized via microwave-assisted heating ascorbic acid and polyethyleneimine. The synthesized CDots can induce the epithelial-mesenchymal transition (EMT) process by activating transforming growth factor-β/p-38 mitogen-activated kinase/Snail signaling pathway, leading to an increase of cell motility. Further, by assessing a series of in vivo wound healing assays and histological examinations, it is demonstrated that CDots can accelerate the migration of epithelial cells in the full-thickness cutaneous wounds through EMT. As a result, a rapid re-epithelialization covers the granulation tissue and epidermal barrier formed, leading to a block of the external stimuli, reduction of the inflammatory reaction and the granulation tissue area, and finally the promotion of the wound healing with fewer scars.

A multifunctional chemical toolbox to engineer carbon dots for biomedical and energy applications

“…For example, CDs with abundant carboxylate and amino groups were prepared from ascorbic acid and polyethyleneimine. 135 These surface functional groups camouflage CDs as cystine knots, which are hallmarks of ligands able to recognize the receptors of the transforming growth factor-. As a result of this targeting ability, CDs promoted wound healing.…”

“…134 c, Surface functional groups trigger selective biological interactions or impart biological properties. 135,136,142 d, Amidation reactions can be used to achieve improved and/or synergistic phototherapies. 148 e, Assembly strategies enhance the NIR absorption properties and the therapeutic efficiency.…”

“…b, Exchangeable protons of the surface functional groups give chemical exchange saturation transfer magnetic resonance imaging properties. 134 c, Surface functional groups trigger selective biological interactions or impart biological properties 135,136,142. d, Amidation reactions can be used to achieve improved and/or synergistic phototherapies.…”

Dendritic Hydrogels with Robust Inherent Antibacterial Properties for Promoting Bacteria-Infected Wound Healing

“…The skin plays a vital role in human health and safety as it is the first barrier against external bacterial and viral invasion. However, the skin is the easiest to be invaded; severe open injuries or burns can cause the skin to lose its protective mechanism. − At the same time, some internal and external influences will hinder wound healing, resulting in unhealable chronic wounds, such as bacterial infections, , diabetes, , and pressure sores. , Especially, once the skin is damaged, harmful bacteria on the skin surface will invade the skin layer or subcutaneous tissues and even cause severe wound infection and tissue damage. , Wound infections can expand, leading to additional treatment costs, treatment failure, and even death. , A typical example is the chronic diabetic foot ulcer, which is often accompanied by severe infections and a slow healing process, , resulting in severely negative consequences such as amputation and sepsis. , Thus, it is highly desirable to develop multifunctional wound dressing to treat wound hemorrhage and infection.…”

“…10,11 Wound infections can expand, leading to additional treatment costs, treatment failure, and even death. 12,13 A typical example is the chronic diabetic foot ulcer, which is often accompanied by severe infections and a slow healing process, 14,15 resulting in severely negative consequences such as amputation and sepsis. 16,17 Thus, it is highly desirable to develop multifunctional wound dressing to treat wound hemorrhage and infection.…”