Freeze-dried bovine amniotic membrane as a cell delivery scaffold in a porcine model of radiation-induced chronic wounds

The Effects of Extracorporeal Shock Wave Therapy on Cutaneous Radiation Injury in a Mouse Model

BACKGROUND

Although radiation-induced skin injuries are a concern in patients receiving radiation therapy, there are few effective treatments. The aim of this study was to evaluate the protective effects of extracorporeal shock wave therapy (ESWT) on irradiated fibroblasts and mouse skin.

METHODS

In this in vitro study of human dermal fibroblasts, the experimental group was subjected to ESWT after irradiation (20 Gy). The control groups were only irradiated or only subjected to ESWT. At 24 or 48 hours after ESWT, cell viability, cell migration, and mRNA and protein expression were measured. In the in vivo study, the experimental group (7 mice) was treated with ESWT after irradiation (45 Gy). The control group (7 mice) was only irradiated. At 8 weeks after irradiation, dorsal skin was harvested for histopathologic examination and protein isolation.

RESULTS

In dermal fibroblasts, treatment with ESWT increased viability of irradiated cells compared with irradiated-only and untreated cells ( P = 0.005). ESWT increased cell migration 24 hours after irradiation ( P = 0.002) and decreased transforming growth factor-β (TGF-β) protein expression 48 hours after irradiation ( P = 0.024). In mice, ESWT decreased the level of radiation-related skin injury ( P = 0.006). Treatment of irradiated skin with ESWT decreased TGF-β1 ( P = 0.009) and phospho-Smad3 ( P = 0.009) protein expression, decreased myofibroblasts ( P = 0.047), and increased vessel density ( P < 0.001).

CONCLUSION

This study demonstrated that ESWT alleviated radiation-induced fibrosis by downregulating TGF-β1 expression, suggesting the potential of ESWT for the treatment of radiation-induced fibrosis.

Analysis of morphology, cytotoxicity, and water content characteristics of freeze-dried amnion membrane from human and bovine

Placenta tissue has biological advantages, including anti-inflammatory, anti-bacterial, anti-fibrotic formation, and immunomodulatory properties. The amnion membrane (AM) is an inner side membrane of the placenta that faces the fetus. The main sources of amnion are humans and animals, with bovine being one of the significant sources. The aim of this study was to analyze the morphology, cytotoxicity, and water content characteristic of freeze-dried amnion membrane (FD-AM) from humans and bovines to measure the safety and compatibility of bovine FD-AM as an alternative to human FD-AM. This study is an observational cross-sectional study. Samples were divided into two groups: human FD-AM and bovine FD-AM groups. Both groups were examined for morphology characteristics by scanning electron microscopy (SEM), cytotoxicity by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) analysis, and water content by drying through moisture analyzer device. The morphology characteristics of bovine FD-AM and human FD-AM, as observed through SEM, showed similar results of a smooth, flat surface with no cavity and were well dehydrated. MTT assay analysis on both groups demonstrated cytocompatibility with cell viability exceeding 70% in the control group. However, human FD-AM showed a higher number of viable cells (0.19±0.01) compared to bovine FD-AM (0.12±0.03), with a statistically significant difference (p<0.05). The water content analysis revealed that both groups met the standard, with levels below 10%. While bovine FD-AM (7.19±0.45%) had slightly higher water content than human FD-AM (6.79±1.0%), the difference was not significant (p>0.05). Both human FD-AM and bovine FD-AM showed good results in morphology, cytotoxicity, and water content characteristics and compatibility. In conclusion, bovine FD-AM might be considered as an alternative to human FD-AM.

Wound healing induced by new synthetic peptide, A7-1, in C57BL/6 mouse model

The effects of the novel synthetic peptide, A7-1, on wound healing and skin grafts were evaluated in a C57BL/6 mouse model. Two 15-mm wide circular skin excisions were made on the backs of mice and to each excision, 100 µM A7-1 or normal saline was applied daily. The treatments were applied and sutured for skin graft analysis. Digital photos were acquired on days 4, 7, 11, and 14 and fluorescein angiography was conducted. Wound sizes were verified using stereoscopic microscopy. Histological analysis was performed via hematoxylin and eosin staining and Masson's trichrome staining. Western blotting was performed using vascular endothelial growth factor. Using a stereoscopic microscope, significantly faster wound healing (17.3%) and skin graft healing (16.5%) were observed in the A7-1 treatment group in comparison to that of the control. The angiogenesis was significantly faster in fluorescein angiography examination in wound healing (11%) and skin grafts (15%). However, the average completion of epithelization (overall time for wound healing), did not show any significant differences. In comparison to the control, the new protein, A7-1, led to significantly faster wound healing in the initial angiogenesis.

Successful Treatment of Wound Dehiscence by Innovative Type 1 Collagen Flowable Gel: A Case Report

The growing demand for postbariatric body-contouring surgery after massive weight loss goes hand-in-hand with an increase in wound complications. Consequently, surgical reoperation or conservative management is necessary and represents a difficult challenge to healthcare professionals. Moreover, it is well known that postbariatric patients present aberrant wound healing due to multifactorial causes, such as preoperative illness, nutritional deficiencies, and vascular disease. To treat such complex wounds, several methods have been recommended, such as the use of negative pressure wound therapy, tissue-engineered skin substitutes, and collagen-based wound dressings. The case presented here is of a patient with deep wound dehiscence of the inner left thigh, 1 week after a medial thigh lift procedure, successfully managed with Vergenix Flowable Gel, a human recombinant type I collagen produced in plants. After 2 weeks of treatment, wound dehiscence was replaced with granulation tissue, and after 4 weeks, the patient was completely healed, with an acceptable aesthetic outcome of the surgical scar.