Zwitterionic hydrogel for sustained release of growth factors to enhance wound healing

Ocular chemical burns are potentially blinding ocular injuries and require urgent management. Amniotic membrane (AM) transplantation is an effective surgical treatment, one of the reasons is because AM is a rich source of growth factors that can promote epithelialization and wound healing. However, growth factors will be gradually lost and insufficient after preparation process and long-time storage, leading to unsatisfactory therapeutic effects. Herein, we present a modified AM (AM-HEP) for the supplement and sustained release of growth factor by surface grafting heparin for treatment of ocular chemical burns. Heparin grafting rate and stability, microstructure, physical property, and sustained release of epithelial growth factor (EGF) of AM-HEP were characterized. Biocompatibility and ability to promote corneal epithelial cell growth and migration were evaluated and compared with a biological amnion, which is available on the market in vitro. The therapeutic effects of AM-HEP combined with EGF (AM-HEP@EGF) in vivo had been evaluated in a model of mouse corneal alkali burn. The results indicated that heparin was introduced into AM and maintain stability over 3 weeks at 37°C. The modification process of AM-HEP did not affect microstructure and physical property after comparing with non-modified AM. EGF could be combined quickly and effectively with AM-HEP; the sustained release could last for more than 14 days. AM-HEP@EGF could significantly promote corneal epithelial cell growth and migration, compared with non-modified AM and control group. Faster corneal epithelialization was observed with the transplantation of AM-HEP@EGF in vivo, compared with the untreated control group. The corneas in the AM-HEP@EGF group have less inflammation and were more transparent than those in the control group. The results from in vitro and in vivo experiments demonstrated that AM-HEP@EGF could significantly enhance the therapeutic effects. Taken together, AM-HEP@EGF is exhibited to be a potent clinical application in corneal alkali burns through accelerating corneal epithelial wound healing.

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Lessons From Epithelialization: The Reason Behind Moist Wound Environment

The Open Dermatology Journal ◽

10.2174/1874372201913010034 ◽

2019 ◽

Vol 13 (1) ◽

pp. 34-40

Author(s):

Sukmawati Tansil Tan ◽

Ricky Dosan

Keyword(s):

Stem Cells ◽

Wound Healing ◽

Cell Migration ◽

Growth Factors ◽

Epithelial Cells ◽

Epidermal Cell ◽

Major Aspect ◽

Proliferative Phase ◽

Wounded Area ◽

Enhance Wound Healing

Wound healing consists of multiple structured mechanism and is influenced by various factors. Epithelialization is one of the major aspect in wound healing and inhibition of this mechanism will greatly impair wound healing. Epithelialization is a process where epithelial cells migrate upwards and repair the wounded area. This process is the most essential part in wound healing and occurs in proliferative phase of wound healing. Skin stem cells which reside in several locations of epidermis contribute in the re-epithelialization when the skin is damaged. Epithelialization process is activated by inflammatory signal and then keratinocyte migrate, differentiate and stratify to close the defect in the skin. Several theories of epithelialization model in wound healing have been proposed for decades and have shown the mechanism of epidermal cell migration during epithelialization even though the exact mechanism is still controversial. This process is known to be influenced by the wound environment where moist wound environment is preferred rather than dry wound environment. In dry wound environment, epithelialization is known to be inhibited because of scab or crust which is formed from dehydrated and dead cells. Moist wound environment enhances the epithelialization process by easier migration of epidermal cells, faster epithelialization, and prolonged presence of proteinases and growth factors. This article focuses on the epithelialization process in wound healing, epithelialization models, effects of wound environment on epithelialization and epithelialization as the basis for products that enhance wound healing.

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Enhanced skin wound healing by a sustained release of growth factors contained in platelet-rich plasma

Experimental & Molecular Medicine ◽

10.3858/emm.2011.43.11.070 ◽

2011 ◽

Vol 43 (11) ◽

pp. 622 ◽

Cited By ~ 65

Author(s):

Hee Seok Yang ◽

Jaehoon Shin ◽

Suk Ho Bhang ◽

Jung-Youn Shin ◽

Jooyeon Park ◽

...

Keyword(s):

Wound Healing ◽

Growth Factors ◽

Sustained Release ◽

Platelet Rich Plasma ◽

Skin Wound ◽

Skin Wound Healing

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Human Adipose-Derived Stem Cell Secreted Extracellular Matrix Incorporated into Electrospun Poly(Lactic-co-Glycolic Acid) Nanofibrous Dressing for Enhancing Wound Healing

Polymers ◽

10.3390/polym11101609 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1609 ◽

Cited By ~ 6

Author(s):

Tang ◽

Yang ◽

Lin ◽

Chen ◽

Lu ◽

...

Keyword(s):

Extracellular Matrix ◽

Wound Healing ◽

Growth Factors ◽

Wound Dressing ◽

Type I Collagen ◽

Healing Process ◽

Wound Dressings ◽

Random Structure ◽

Type I ◽

Enhance Wound Healing

Wound dressing, which prevents dehydration and provides a physical barrier against infection to wound beds, can improve wound healing. The interactions between extracellular matrix (ECM) and growth factors is critical to the healing process. Electrospun nanofibers are promising templates for wound dressings due to the structure similarity to ECM of skin. Otherwise, the ECM secreted by human adipose-derived stem cells (hASCs) is rich in growth factors known to enhance wound healing. Accordingly, we propose that the PLGA nanofibrous template incorporated with hASCs-secreted ECM may enhance wound healing. In this study, PLGA nanofibrous matrixes with an aligned or a random structure were prepared by electrospinning. Human ASCs cultured on the aligned matrix had a better viability and produced a larger amount of ECM relative to that of random one. After 7 days’ cultivation, the hASCs on aligned PLGA substrates underwent decellularization to fabricate cECM/PLGA dressings. By using immunohistochemical staining against F-actin and cell nucleus, the removal of cellular components was verified. However, the type I collagen and laminin were well preserved on the cECM/PLGA nanofibrous matrixes. In addition, this substrate was hydrophilic, with appropriate mechanical strength to act as a wound dressing. The L929 fibroblasts had good activity, survival and proliferation on the cECM/PLGA meshes. In addition, the cECM/PLGA nanofibrous dressings improved the wound healing of surgically created full-thickness skin excision in a mouse model. This hASCs-secreted ECM incorporated into electrospun PLGA nanofibrous could be a promising dressing for enhancing wound healing.

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