CO2 Fractional Laser Combined with 5-Fluorouracil Ethosomal Gel Treatment of Hypertrophic Scar Macro-, Microscopic, and Molecular Mechanism of Action in a Rabbit Animal Model

Preparation of Compound Salvia miltiorrhiza-Blumea balsamifera Nanoemulsion Gel and Its Effect on Hypertrophic Scars in the Rabbit Ear Model

Hypertrophic scars (HS) still remain an urgent challenge in the medical community. Traditional Chinese medicine (TCM) has unique advantages in the treatment of HS. However, due to the natural barrier of the skin, it is difficult for the natural active components of TCM to more effectively penetrate the skin and exert therapeutic effects. Therefore, the development of an efficient drug delivery system to facilitate enhanced transdermal absorption of TCM becomes imperative for its clinical application. In this study, we designed a compound Salvia miltiorrhiza-Blumea balsamifera nanoemulsion gel (CSB-NEG) and investigated its therapeutic effects on rabbit HS models. The prescription of CSB-NEG was optimized by single-factor, pseudoternary phase diagram, and central composite design experiments. The results showed that the average particle size and PDI of the optimized CSB-NE were 46.0 ± 0.2 nm and 0.222 ± 0.004, respectively, and the encapsulation efficiency of total phenolic acid was 93.37 ± 2.56%. CSB-NEG demonstrated excellent stability and skin permeation in vitro and displayed a significantly enhanced ability to inhibit scar formation compared to the CSB physical mixture in vivo. After 3 weeks of CSB-NEG treatment, the scar appeared to be flat, pink, and flexible. Furthermore, this treatment also resulted in a decrease in the levels of the collagen I/III ratio and TGF-β1 and Smad2 proteins while simultaneously promoting the growth and remodeling of microvessels. These findings suggest that CSB-NEG has the potential to effectively address the barrier properties of the skin and provide therapeutic benefits for HS, offering a new perspective for the prevention and treatment of HS.

Clinical efficacy of CO2 fractional laser in treating post-burn hypertrophic scars in children: A meta-analysis: CO2 fractional laser in treating post-burn hypertrophic scars in children

OBJECTIVE

To evaluate and explore the efficacy of CO2 fractional laser in treating post-burn hypertrophic scars in children through Meta-analysis.

METHODS

English databases (PubMed, Web of Science and The National Library of Medicine), as well as Chinese databases (China National Knowledge Infrastructure and Wanfang Data) were searched. RevMan 5.3 software was used to data analysis.

RESULTS

A total of 10 pieces of literature were included, involving 413 children. Meta-analysis showed that: (1) The average Vancouver Scar Scale after surgery was significantly lower than that before surgery [weight mean difference (WMD) = -3.56, 95% confidence interval (CI):-4.53,-2.58, p < 0.001]; (2) After CO2 fractional laser, pigmentation [WMD = -0.74, 95% CI:-1.10,-0.38, p < 0.001], pliability [WMD = -0.92, 95% CI:-1.20,-0.65, p < 0.001], vascularity [WMD = -0.77, 95% CI:-1.09,-0.46, p < 0.001], height [WMD = -0.57, 95% CI:-0.95,-0.19, p < 0.001] were improved compared with those before surgery. (3) The average Visual Analogue Scale (VAS) after surgery was significantly lower than that before surgery [WMD = -3.94, 95% CI:-5.69,-2.22, p < 0.001]. (4) Both Patient and Observer Scar Assessment Scale (POSAS)-Observer [WMD = -3.98, 95% CI:-8.44,0.47, p < 0.001] and POSAS-Patient [WMD = -4.98, 95% CI:-8.09,-1.87, p < 0.001] were significantly lower than those before surgery. (5) Erythema and vesicles were the most common complications after CO2 fractional laser therapy, with an incidence of 4.09%.

CONCLUSION

CO2 fractional laser is beneficial to the recovery of hypertrophic scar after burn in children, and can effectively improve the scar symptoms and signs in children, with desirable clinical efficacy.

CO2 Laser for Esthetic Healing of Injuries and Surgical Wounds with Small Parenchymal Defects in Oral Soft Tissues

A number of studies have recently demonstrated the effectiveness of CO2 laser irradiation for the repair and regeneration of scar tissue from injuries or surgical wounds. However, such studies of the oral mucosa are highly limited. Previous studies using CO2 laser irradiation have indicated that two factors contribute to esthetic healing, namely, artificial scabs, which are a coagulated and carbonized blood layer formed on the wound surface, and photobiomodulation therapy (PBMT) for suppressing wound scarring and promoting wound healing. This review outlines basic research and clinical studies of esthetic healing with the use of a CO2 laser for both artificial scab formation by high-intensity laser therapy and PBMT in the treatment of injuries and surgical wounds with small parenchymal defects in oral soft tissues. The results showed that the wound surface was covered by an artificial scab, enabling the accumulation of blood and the perfusion necessary for tissue regeneration and repair. Subsequent PBMT also downregulated the expression of transformation growth factor-b1, which is involved in tissue scarring, and decreased the appearance of myofibroblasts. Taken together, artificial scabs and PBMT using CO2 lasers contribute to the suppression of scarring in the tissue repair process, leading to favorable esthetic and functional outcomes of wound healing.

An Updated Review of Hypertrophic Scarring

Hypertrophic scarring (HTS) is an aberrant form of wound healing that is associated with excessive deposition of extracellular matrix and connective tissue at the site of injury. In this review article, we provide an overview of normal (acute) wound healing phases (hemostasis, inflammation, proliferation, and remodeling). We next discuss the dysregulated and/or impaired mechanisms in wound healing phases that are associated with HTS development. We next discuss the animal models of HTS and their limitations, and review the current and emerging treatments of HTS.

Research trends and hotspot analysis of fractional carbon dioxide laser: A bibliometric and visualized analysis via Citespace

INTRODUCTION

There is limited basic research on carbon dioxide (CO₂ ) fractional laser, indicating blind spots in CO₂ fractional laser treatment of certain diseases. This study aimed to organize previous literature, summarize the current research, and speculate on possible future development.

METHODS

We searched document data on fractional CO₂ lasers from the Web of Science core collection database and retrieved 928 articles from 2004 to 2021. CiteSpace software was used to analyze the main institutions, authors, subject hotspots, and research frontiers in global CO₂ fractional laser research.

RESULTS

The results revealed that 928 related papers were published in the past 18 years (2004-2021), and the number has increased annually. The publications were written by 3239 authors from 626 institutions in 60 countries/regions. The United States (US) dominates this field (312 documents), followed by Italy (289), and South Korea (88). Lasers in Surgery and Medicine is the journal with the most publications and citations, and Uebelhoer is the central author. The main research hotspots include vulvovaginal atrophy, fractional photothermolysis, keloids, drug delivery, gene expressions, facial acne scarring, resurfacing, vitiligo, and photo damage.

CONCLUSION

Using CiteSpace, this paper draws a map of authors, institutions, and keywords in fractional CO₂ laser from 2004 to 2021; summarizes the main authors, institutions, research hotspots, and cutting-edge topics of global fractional CO₂ laser technology in recent years; and summarizes the current application status of global fractional CO₂ laser in disease treatment. It also provides new ideas for the future application and research of fractional CO₂ lasers.

Effect of THBS1 on the Biological Function of Hypertrophic Scar Fibroblasts

Hypertrophic scarring is a skin collagen disease that can occur following skin damage and is unlikely to heal or subside naturally. Since surgical treatment often worsens scarring, it is important to investigate the pathogenesis and prevention of hypertrophic scarring. Thrombospondin-1 (THBS1) is a matrix glycoprotein that can affect fibrosis by activating TGF-β1, which plays a key role in wound repair and tissue regeneration; therefore, we investigated the effects of THBS1 on the biological function of hypertrophic scar fibroblasts. THBS1 expression was measured in hypertrophic scars and adjacent tissues as well as normal fibroblasts, normal scar fibroblasts, and hypertrophic scar fibroblasts. In addition, THBS1 was overexpressed or silenced in hypertrophic scar fibroblasts to determine the effects of THBS1 on cell proliferation, apoptosis, and migration, as well as TGF-β1 expression. Finally, the role of THBS1 in hypertrophic scarring was confirmed in vivo using a mouse model. We found that THBS1 expression was increased in hypertrophic scar tissues and fibroblasts and promoted the growth and migration of hypertrophic scar fibroblasts as well as TGF-β1 expression. Interestingly, we found that si-THBS1 inhibited the occurrence and development of bleomycin-induced hypertrophic scars in vivo and downregulated TGF-β1 expression. Together, our findings suggest that THBS1 is abnormally expressed in hypertrophic scars and can induce the growth of hypertrophic scar fibroblasts by regulating TGF-β1. Consequently, THBS1 could be an ideal target for treating hypertrophic scarring.