Topical treatment with basic fibroblast growth factor promotes wound healing and barrier recovery induced by skin abrasion

Evaluation of viscoelastic parameters and photo-based assessment of newly developed dermal substitutes modified with thermostabilized fibroblast growth factor 2

BACKGROUND

The purpose of dermal substitutes is to mimic the basic properties of the extracellular matrix of human skin. The application of dermal substitutes to the defect reduces the formation of hypertrophic scars and improves the scar quality. This study aims to develop an original dermal substitute enriched with stable fibroblast growth factor 2 (FGF2-STAB®) and test it in an animal model.

METHODS

Dermal substitutes based on collagen/chitosan scaffolds or collagen/chitosan scaffolds with nanofibrous layer were prepared and enriched with FGF2-STAB® at concentrations of 0, 0.1, 1.0, and 10.0 µg ‧ cm-2. The performance of these dermal substitutes was tested in vivo on artificially formed skin defects in female swine. The outcomes were evaluated using cutometry at 3 and 6 months. In addition, visual appearance was assessed based on photos of the scars at 1-month, 3-month and 6-month follow-ups using Yeong scale and Visual Analog Scale.

RESULTS

The dermal substitute was fully integrated into all defects and all wounds healed successfully. FGF2-STAB®-enriched matrices yielded better results in cutometry compared to scaffolds without FGF2. Visual evaluation at 1, 3, and 6 months follow-ups detected no significant differences among groups. The FGF2-STAB® effectiveness in improving the elasticity of scar tissues was confirmed in the swine model. This effect was independently observed in the scaffolds with nanofibres as well as in the scaffolds without nanofibres.

CONCLUSION

The formation of scars with the best elasticity was exhibited by addition 1.0 µg ‧ cm-2of FGF2-STAB® into the scaffolds, although it had no significant effect on visual appearance at longer follow-ups. This study creates the basis for further translational studies of the developed product and its progression into the clinical phase of the research.

Glycosylation of FGF/FGFR: An underrated sweet code regulating cellular signaling programs

Fibroblast growth factors (FGFs) and their receptors (FGFRs) constitute plasma-membrane localized signaling hubs that transmit signals from the extracellular environment to the cell interior, governing pivotal cellular processes like motility, metabolism, differentiation, division and death. FGF/FGFR signaling is critical for human body development and homeostasis; dysregulation of FGF/FGFR units is observed in numerous developmental diseases and in about 10% of human cancers. Glycosylation is a highly abundant posttranslational modification that is critical for physiological and pathological functions of the cell. Glycosylation is also very common within FGF/FGFR signaling hubs. Vast majority of FGFs (15 out of 22 members) are N-glycosylated and few FGFs are O-glycosylated. Glycosylation is even more abundant within FGFRs; all FGFRs are heavily N-glycosylated in numerous positions within their extracellular domains. A growing number of studies points on the multiple roles of glycosylation in fine-tuning FGF/FGFR signaling. Glycosylation modifies secretion of FGFs, determines their stability and affects interaction with FGFRs and co-receptors. Glycosylation of FGFRs determines their intracellular sorting, constitutes autoinhibitory mechanism within FGFRs and adjusts FGF and co-receptor recognition. Sugar chains attached to FGFs and FGFRs constitute also a form of code that is differentially decrypted by extracellular lectins, galectins, which transform FGF/FGFR signaling at multiple levels. This review focuses on the identified functions of glycosylation within FGFs and FGFRs and discusses their relevance for the cell physiology in health and disease.

Recent advancements in natural polymers-based self-healing nano-materials for wound dressing

The field of wound healing has witnessed remarkable progress in recent years, driven by the pursuit of advanced wound dressings. Traditional dressing materials have limitations like poor biocompatibility, nonbiodegradability, inadequate moisture management, poor breathability, lack of inherent therapeutic properties, and environmental impacts. There is a compelling demand for innovative solutions to transcend the constraints of conventional dressing materials for optimal wound care. In this extensive review, the therapeutic potential of natural polymers as the foundation for the development of self-healing nano-materials, specifically for wound dressing applications, has been elucidated. Natural polymers offer a multitude of advantages, possessing exceptional biocompatibility, biodegradability, and bioactivity. The intricate engineering strategies employed to fabricate these polymers into nanostructures, thereby imparting enhanced mechanical robustness, flexibility, critical for efficacious wound management has been expounded. By harnessing the inherent properties of natural polymers, including chitosan, alginate, collagen, hyaluronic acid, and so on, and integrating the concept of self-healing materials, a comprehensive overview of the cutting-edge research in this emerging field is presented in the review. Furthermore, the inherent self-healing attributes of these materials, wherein they exhibit innate capabilities to autonomously rectify any damage or disruption upon exposure to moisture or body fluids, reducing frequent dressing replacements have also been explored. This review consolidates the existing knowledge landscape, accentuating the benefits and challenges associated with these pioneering materials while concurrently paving the way for future investigations and translational applications in the realm of wound healing.

An Overview of Growth Factors as the Potential Link between Psoriasis and Metabolic Syndrome

Psoriasis is a chronic, complex, and immunologically mediated systemic disease that not only affects the skin, but also the joints and nails. It may coexist with various other disorders, such as depression, psoriatic arthritis, cardiovascular diseases, diabetes mellitus, and metabolic syndrome. In particular, the potential link between psoriasis and metabolic syndrome is an issue worthy of attention. The dysregulation of growth factors could potentially contribute to the disturbances of keratinocyte proliferation, inflammation, and itch severity. However, the pathophysiology of psoriasis and its comorbidities, such as metabolic syndrome, remains incompletely elucidated. Growth factors and their abnormal metabolism may be a potential link connecting these conditions. Overall, the objective of this review is to analyze the role of growth factor disturbances in both psoriasis and metabolic syndrome.

Effects of dual-gene modification on biological characteristics of vascular endothelial cells and their significance as reserving cells for chronic wound repair

bFGF is a commonly used and reliable factor for improving chronic wound healing, and hSulf-1 expression is abundant in surrounding cells of chronic wound tissue and vascular endothelial cells, which can reverse the effect of bFGF and inhibit the signalling activity of cell proliferation. In this study, an adenovirus, Ad5F35ET1-bFGF-shSulf1, was designed for establishing the dual-gene modified vascular endothelial cells, which were used as the repair cells for skin chronic wound. Ad5F35ET1-bFGF-shSulf1 infected ECV304 cells in vitro and mediated the overexpression of bFGF and the knockdown of hSulf-1, which effectively activated the AKT and ERK signal transduction pathways, facilitate cell proliferation and migration, with the cell viability to 128.29% at 72 h after infection, compared to 66.65%, 73.74%, 87.63%, 103.14% in the blank control, Ad5F35ET1-EGFP-shNC, Ad5F35ET1-shSulf1, Ad5F35ET1-bFGF groups, respectively. In the rat ear skin injury model, the wound healing was significantly accelerated in the Ad5F35ET1-rbFGF-shrSulf1 group compared to the blank control group (p = 0.0046), Ad5F35ET1-EGFP-shNC group (p = 0.0245), Ad5F35ET1-shrSulf group (p = 0.0426), and Ad5F35ET1-rbFGF group (p = 0.2853). The results demonstrated that this strategy may be a candidate therapy for chronic injury repair.

The Antimicrobial Effects of Bacterial Cellulose Produced by Komagataeibacter intermedius in Promoting Wound Healing in Diabetic Mice

As a conventional medical dressing, medical gauze does not adequately protect complex and hard-to-heal diabetic wounds and is likely to permit bacterial entry and infections. Therefore, it is necessary to develop novel dressings to promote wound healing in diabetic patients. Komagataeibacter intermedius was used to produce unmodified bacterial cellulose, which is rarely applied directly to diabetic wounds. The produced cellulose was evaluated for wound recovery rate, level of inflammation, epidermal histopathology, and antimicrobial activities in treated wounds. Diabetic mices' wounds treated with bacterial cellulose healed 1.63 times faster than those treated with gauze; the values for the skin indicators in bacterial cellulose treated wounds were more significant than those treated with gauze. Bacterial cellulose was more effective than gauze in promoting tissue proliferation with more complete epidermal layers and the formation of compact collagen in the histological examination. Moreover, wounds treated with bacterial cellulose alone had less water and glucose content than those treated with gauze; this led to an increase of 6.82 times in antimicrobial protection, lower levels of TNF-α and IL-6 (39.6% and 83.2%), and higher levels of IL-10 (2.07 times) than in mice wounds treated with gauze. The results show that bacterial cellulose produced using K. intermedius beneficially affects diabetic wound healing and creates a hygienic microenvironment by preventing inflammation. We suggest that bacterial cellulose can replace medical gauze as a wound dressing for diabetic patients.

Approaches for Regenerative Healing of Cutaneous Wound with an Emphasis on Strategies Activating the Wnt/β-Catenin Pathway

Significance: In adult mammals, spontaneous repair of a cutaneous wound occurs slowly and leaves a scar with skin adnexa deficiencies. To accelerate cutaneous wound-healing rates and avoid scar formation, current studies have focused on regenerative therapies. Recent Advances: Emerging therapeutics for regenerative wound healing often focus on the use of growth factors and stem cells. However, these therapeutic approaches have limited routine clinical use due to high costs and technical requirements. Critical Issue: Understanding the molecular mechanisms involved in the signaling pathways for cutaneous wound healing and neogenic synthesis of the skin components is important for identification of novel targets for the development of regenerative wound-healing agents. Future Directions: The Wnt/β-catenin pathway is a well-known key player for enhancement of the overall healing process involving tissue regeneration via crosstalk with other signaling pathways. Strategies that activate the Wnt/β-catenin pathway via modulation of the pathway-controlling regulatory factors could provide effective therapeutic approaches for regenerative wound healing.

The Role of Fibroblast Growth Factor (FGF) Signaling in Tissue Repair and Regeneration

Fibroblast growth factors (FGFs) are a large family of secretory molecules that act through tyrosine kinase receptors known as FGF receptors. They play crucial roles in a wide variety of cellular functions, including cell proliferation, survival, metabolism, morphogenesis, and differentiation, as well as in tissue repair and regeneration. The signaling pathways regulated by FGFs include RAS/mitogen-activated protein kinase (MAPK), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)–protein kinase B (AKT), phospholipase C gamma (PLCγ), and signal transducer and activator of transcription (STAT). To date, 22 FGFs have been discovered, involved in different functions in the body. Several FGFs directly or indirectly interfere with repair during tissue regeneration, in addition to their critical functions in the maintenance of pluripotency and dedifferentiation of stem cells. In this review, we summarize the roles of FGFs in diverse cellular processes and shed light on the importance of FGF signaling in mechanisms of tissue repair and regeneration.

Fibroblast growth factor 2 accelerates the epithelial-mesenchymal transition in keratinocytes during wound healing process

In the wound healing process, the morphology of keratinocytes at the wound edge temporarily changes to a spindle morphology, which is thought to occur due to an epithelial–mesenchymal transition (EMT). Fibroblast growth factor (FGF) 2, also called basic FGF, has the potential to accelerate wound closure by activating vascular endothelial cells and fibroblasts. We examined the effects of FGF2 on keratinocyte morphology and EMT in wounded skin. Histological examination of murine wounds treated with FGF2 revealed that wound edge keratinocytes formed thickened and multilayered epithelia. In addition, we detected wound edge keratinocytes migrating individually toward the wound center. These migrating keratinocytes exhibited not only spindle morphology but also down-regulated E-cadherin and up-regulated vimentin expression, which is characteristic of EMT. In FGF2-treated wounds, a PCR array revealed the upregulation of genes related to EMT, including transforming growth factor (TGF) signaling. Further, FGF2-treated wound edge keratinocytes expressed EMT-associated transcription factors, including Snai2, and showed translocation of β-catenin from the cell membrane to the cytoplasm/nucleus. However, in vitro examination of keratinocytes revealed that FGF2 alone did not activate EMT in keratinocytes, but that FGF2 might promote EMT in combination with TGFβ1. These findings suggest that FGF2 treatment of wounds could promote keratinocyte EMT, accelerating wound closure.

Healing effects of natural latex serum 1% from Hevea brasiliensis in an experimental skin abrasion wound model

Background

Dermabrasion is related with mechanical and surgical traumas on the skin; usually topical antiseptics and/or saline have been used for healing. Natural products for wound healing can also be used for abrasions, such as latex from Hevea brasiliensis.

Objective

This study aimed to evaluate the in vitro viability and migratory/proliferative effects of latex serum from H. brasiliensis and to compare with a commercially available standard antiseptic solution and saline in experimental dermabrasion on rats.

Methods

For in vitro evaluation, MTT and scratch assays were used. In vivo testing was performed in 72 rats submitted to dermabrasion, treated with saline, antiseptic, or latex serum. This study evaluated re-epithelialization, neutrophilic infiltration, and the quantification of crust and epidermis.

Results

Latex showed viability at 1% and 0.1% concentrations and migratory/proliferative activity at 0.01% concentrations. The re-epithelialization was highest in latex group on 7th day. The latex group displayed lower thickness of crusts and greater extent of epidermal layers. The latex and antiseptic groups showed increases of myeloperoxidase levels on the 2nd day and showed important reductions from the 7th day.

Study limitations

Acute superficial wound model in rats and non-use of gel-cream (medium) without latex.

Conclusion

In conclusion, non-toxic latex stimulated migration/proliferation of keratinocytes in vitro and significantly accelerated wound healing in animal excoriation models compared to chlorhexidine or saline.

Randomized trial of electrodynamic microneedle combined with 5% minoxidil topical solution for the treatment of Chinese male Androgenetic alopecia

Background: In treating androgenetic alopecia, 5% minoxidil is a commonly used topical drug. By using electrodynamic microneedle at the same time may increase absorption of minoxidil and further stimulate hair growth.Objective: A 24-week, randomized, evaluator blinded, comparative study was performed to evaluate the efficacy of treating Chinese male androgenetic alopecia using microneedle combined with 5% minoxidil topical solution. Methods: Randomized subjects received topical 5% minoxidil (group 1, n = 20), local electrodynamic microneedle treatments (group 2, n = 20), or local electrodynamic microneedle treatments plus topical 5% minoxidil (group 3, n = 20). A total of 12 microneedle treatments were performed every 2 weeks with 2ml 5% minoxidil delivery in group three during each microneedle treatment. Patient receiving topical 5% minoxidil applied 1 ml of the solution twice daily over the course of the study. A total of 60 Chinese male subjects with Norwood-Hamilton type III-VI androgenetic alopecia were treated.Results: The mean improvement in total hair density from baseline to 24 weeks was 18.8/cm² in group 1, 23.4/cm² in group 2, and 38.3/cm² in group 3. The hair growth in the three groups was significantly different (P = 0.002), but there were no significant differences in toxicity found between the three groups.Conclusions: Treatment with microneedle plus topical 5% minoxidil was associated with the best hair growth.

Skin Improvement Effects of Gardeniae fructus Extract in HaCaT Keratinocytes, B16F10 Melanocytes, and CCD-986sk Fibroblast Cells

The development of functional cosmetics with skin improvement effects from natural sources is necessary. In this study, the antioxidant, antiwrinkling, moisturizing, and whitening effects of Gardeniae fructus extract (GF) were investigated in keratinocytes, melanocytes, and fibroblast cells. Antioxidant activity was determined by a DPPH free radical scavenging assay. MMP-1, MMP-9, HAS1, and filaggrin mRNA levels were measured by RT-PCR in keratinocytes and fibroblast cells. MITF and tyrosinase protein levels were evaluated by blotting analysis in melanocytes. DPPH free radical activity was investigated to determine whether GF showed dose-dependent inhibitory activity. GF induced the upregulation of HAS1 and filaggrin mRNA expression in keratinocytes and fibroblast cells. GF led to the downregulation of MMP mRNA levels in keratinocytes and fibroblast cells. Western blotting was performed to confirm the whitening-related protein (MITF and tyrosinase) levels induced by GF in melanocytes, and the inhibitory activity was superior to that of the α-MSH used for the comparison test. GF showed marked antioxidant, antiwrinkling, skin moisturizing, and whitening activity in keratinocytes, melanocytes, and fibroblast cells. Through the results of these experiments, the applicability of GF as a natural and functional cosmetic material was verified.

Adipokine concentrations in lipoaspirates may have a role in wound healing

OBJECTIVES

In addition to its use as a volume filler, fat grafting may have a potential role in wound healing based on the concentration of growth factors in the lipoaspirate. In this study, we compare the quantitative and qualitative concentration of the various growth factors and adipokines using the Shippert or the Coleman techniques to prepare the lipoaspirate.

METHODS

We measured leptin, adiponectin and the growth factors, i.e., acidic fibroblast growth factor (aFGF), basic FGF (bFGF), keratinocyte growth factor (KGF), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) by ELISA in solid and liquid fractions obtained with both techniques in human fat obtained with Coleman technique and Shippert technique.

RESULTS

All of these peptides, except BMP-2, were detected in relevant quantities in the solid fraction. The Coleman but not the Shippert technique resulted in statistically higher adiponectin concentrations in the solid tissue fraction. The other four growth factors occurred in significantly higher concentrations in the solid fractions compared to the liquid fractions, independent of the processing technique.

CONCLUSION

In summary, we demonstrated that KGF, aFGF, bFGF and VEGF, as well as leptin and adiponectin, are contained in fat suspensions obtained by liposuction and in the supernatant. Only the concentration of adiponectin was in the range reported to contribute to wound healing.

Carboxyethyl aminobutyric acid (CEGABA) lacks cytotoxicity and genotoxicity and stimulates cell proliferation and migration in vitro

Cosmeceuticals are cosmetics formulated using compounds with medical-like benefits. Though the antiaging effect of carboxyethyl aminobutyric acid (CEGABA) has been discussed, its action mechanism in cosmeceuticals remains unclear. This study assessed the in vitro efficacy and safety of CEGABA. NHI-3T3 mouse fibroblast cell line was treated with two CEGABA concentrations (50 and 500 μmol/L) for 24 h, 48 h, and 72 h. Cytotoxicity and genotoxicity were evaluated by colorimetry (MTT) and the alkaline version of the comet assay, respectively. Flow cytometry and the scratch-wound assay were used to assess cell-cycle phase distributions and cell migration rates. Compared with the untreated control, CEGABA increased cell growth 1.6 times after 72 h, independent of dose. The compound also decreased cell replication time by 4 h. These findings seem to be related with the approximately 1.5-times increase in phase S cells numbers. Importantly, in vitro wound healing improved roughly 20% after treatment with CEGABA for 24 h and persisted after 48 h, indicating culture recovery. The time-dependent proliferation and migration of fibroblasts induced by CEGABA besides the fact that the compound is neither genotoxic nor cytotoxic makes it an ideal candidate in the development of cosmeceuticals in antiaging therapy.

Advances in surgical applications of growth factors for wound healing

Growth factors have recently gained clinical importance for wound management. Application of recombinant growth factors has been shown to mimic cell migration, proliferation, and differentiation in vivo, allowing for external modulation of the healing process. Perioperative drug delivery systems can enhance the biological activity of these growth factors, which have a very short in vivo half-life after topical administration. Although the basic mechanisms of these growth factors are well understood, most have yet to demonstrate a significant impact in animal studies or small-sized clinical trials. In this review, we emphasized currently approved growth factor therapies, including a sustained release system for growth factors, emerging therapies, and future research possibilities combined with surgical procedures. Approaches seeking to understand wound healing at a systemic level are currently ongoing. However, further research and consideration in surgery will be needed to provide definitive confirmation of the efficacy of growth factor therapies for intractable wounds.

A novel dressing seeded with embryonic artery CD133+ cells and loaded with the Sirt1 agonist SRT1720 accelerates the healing of diabetic ischemic ulcers

Refractory ischemic ulcers that occur in patients with diabetes present a major clinical challenge. Embryonic artery cluster of differentiation 133⁺ cells (EACCs) may promote the healing of diabetic ulcers; however, the high glucose environment in the diabetic ulcers decreases the survival rate of transplanted EACCs and inhibit their biological function. Furthermore, microcirculation in diabetic ischemic ulcers is impaired, which inhibits the beneficial effect of EACCs. In the current study, the Sirt1 agonist SRT1720 was selected as a therapeutic drug and loaded into a dressing composed of PLGA, collagen and silk (PCSS) formed using electrospinning technology. EACCs were seeded onto the PCSS dressing and this was used to treat diabetic ulcers. The results indicated that SRT1720 promotes the proliferation of EACCs, enhances the secretion of vascular endothelial growth factor A, interluekin 8 and basic fibroblast growth factor, and inhibits the secretion of tumor necrosis factor α. Furthermore, SRT1720 promoted the paracrine function of EACCs and promoted the proliferation and migration of human umbilical vein endothelial cells. PCSS induced the steady release of SRT1720 over a 15-day period and PCSS seeded with EACCs (PCSS-EACCs) were transplanted into the diabetic ischemic ulcers of mice with diabetes. The results of these experiments indicated that angiogenesis and the healing of diabetic ischemic ulcers was significantly improved following the transplantation of PCSS-EACCs. Therefore, PCSS-EACCs may be a novel and effective treatment for diabetic ischemic ulcers.

Basic Fibroblast Growth Factor Influences Epidermal Homeostasis of Living Skin Equivalents through Affecting Fibroblast Phenotypes and Functions

AIMS

To elucidate the possible mechanisms of how basic fibroblast growth factor (bFGF) influences epidermal homeostasis in a living skin equivalent (LSE) model.

METHODS

Several wound healing-related growth factors were analyzed at protein and mRNA levels for dermal fibroblasts of induced alpha-smooth muscle actin (α-SMA)-positive or α-SMA-negative phenotypes. During culturing an LSE model by seeding normal human keratinocytes on a fibroblast-populated type I collagen gel, bFGF or neutralizing antibody for keratinocyte growth factor (KGF) was added to investigate its effects on fibroblast phenotypes and, subsequently, epidermal homeostasis by histology and immunohistochemistry.

RESULTS

The α-SMA-positive phenotype of fibroblasts induced by transforming growth factor beta-1 (TGF-β1) markedly suppressed the expression of KGF and hepatocyte growth factor (HGF), and slightly upregulated vascular endothelial growth factor (VEGF) and TGF-β1 at mRNA and protein levels, compared with α-SMA-negative fibroblasts treated with bFGF. α-SMA expression of fibroblasts at the epidermal-mesenchymal junction of the LSEs was suppressed by the addition of bFGF, and a better-differentiated epidermis was presented. The abrogation of KGF from fibroblasts by the addition of the KGF neutralizing antibody disenabled the LSE culturing system to develop an epidermis.

CONCLUSIONS

bFGF, through affecting the phenotypes and functions of fibroblasts, especially KGF expression, influenced epidermal homeostasis in an LSE model.

Angiogenesis, Cancer, and Vascular Aging

Several lines of evidence have revealed that the angiogenic response to ischemic injury declines with age, which might account for the increased morbidity and mortality of cardiovascular disease (CVD) among the elderly. While impairment of angiogenesis with aging leads to delayed wound healing or exacerbation of atherosclerotic ischemic diseases, it also inhibits the progression of cancer. Age-related changes of angiogenesis have been considered to at least partly result from vascular aging or endothelial cell senescence. There is considerable evidence supporting the hypothesis that vascular cell senescence contributes to the pathogenesis of age-related CVD, suggesting that vascular aging could be an important therapeutic target. Since therapeutic angiogenesis is now regarded as a promising concept for patients with ischemic CVD, it has become even more important to understand the detailed molecular mechanisms underlying impairment of angiogenesis in older patients. To improve the usefulness of therapeutic angiogenesis, approaches are needed that can compensate for impaired angiogenic capacity in the elderly while not promoting the development or progression of malignancy. In this review, we briefly outline the mechanisms of angiogenesis and vascular aging, followed by a description of how vascular aging leads to impairment of angiogenesis. We also examine potential therapeutic approaches that could enhance angiogenesis and/or vascular function in the elderly, as well as discussing the possibility of anti-senescence therapy or reversal of endothelial cell senescence.

Photodynamic antimicrobial chemotherapy with the novel amino acid-porphyrin conjugate 4I: In vitro and in vivo studies

Photodynamic antimicrobial chemotherapy (PACT), as a novel and effective therapeutic modality to eradicate drug resistant bacteria without provoking multidrug resistance, has attracted increasing attention. This study examined the antimicrobial efficacy of the novel cationic amino acid-porphyrin conjugate 4I with four lysine groups against two different clinical isolated strains (drug sensitive and multidrug resistant) of the Acinetobacter baumannii species and its toxicity on murine dermal fibroblasts in vitro, as well as the therapeutic effect of PACT on acute, potentially lethal multidrug resistant strain excisional wound infections in vivo. The PACT protocol exposed 4I to illumination, exhibiting high antimicrobial efficacy on two different strains due to a high yield of reactive oxygen species (ROS) and non-selectivity to microorganisms. The photoinactivation effects of 4I against two different strains were dose-dependent. At 3.9 μM and 7.8 μM, PACT induced 6 log units of inactivation of sensitive and multidrug resistant strains. In contrast, 4I alone and illumination alone treatments had no visibly antimicrobial effect. Moreover, cytotoxicity tests revealed the great safety of the photosensitizer 4I in mice. In the in vivo study, we found 4I-mediated PACT was not only able to kill bacteria but also accelerated wound recovery. Compared with non-treated mice, over 2.89 log reduction of multidrug resistant Acinetobacter baumannii strain was reached in PACT treat mice at 24 h post-treatment. These results imply that 4I-mediated PACT therapy is an effective and safe alternative to conventional antibiotic therapy and has clinical potential for superficial drug-resistant bacterial infections.

A novel decontaminant and wound healant formulation of N,N'-dichloro-bis[2,4,6-trichlorophenyl]urea against sulfur mustard-induced skin injury

Sulfur mustard (SM)-induced dermatotoxicity can be prevented by an immediate use of decontamination agents. However, practically due to the time lapse between decontamination and exposure, there is always a possibility of wound formation. In view of this, a hydrophilic decontamination formulation of CC-2 (DRDE/WH-03) was fortified with Aloe vera gel and betaine (DRDE/WH-01) for improving its wound healing ability. Swiss albino mice were exposed to SM percutaneously (5 mg/kg) once, and after 24 hours, DRDE/WH-01, DRDE/WH-03, framycetin, and aloe gel were applied topically, daily for 7 days. Skin sections were subjected to histopathology, histomorphologic grading, tissue leukocytosis, and immunohistochemistry of inflammatory-reparative biomarkers on 3 and 7 days, respectively. DRDE/WH-01, framycetin, and aloe gel showed better reepithelialization, angiogenesis, and fibroplasia compared with DRDE/WH-03 and SM control. On the basis of histomorphologic scale, DRDE/WH-01, framycetin, and aloe gel were found to be equally efficacious. Up-regulation of interleukin-6 and infiltrating leukocytes, endothelial nitric oxide synthase and angiogenesis, fibroblast growth factor, and transforming growth factor-alpha with fibroplasia and reepithelialization were well correlated at various stages of the healing process. DRDE/WH-01 was equally effective as framycetin and has shown improved wound healing efficacy compared with DRDE/WH-03. Thus, DRDE/WH-01 can be recommended as a universal decontaminant and wound healant against vesicant-induced skin injury.

A highly infectious chimeric adenovirus expressing basic fibroblast growth factor exerts potent targeted therapy for rabbit ear chronic ischemic wounds

BACKGROUND

Poor angiogenesis and impaired proliferation of cells responsible for the repair of chronic ischemic wounds result in impaired wound healing. The continuous and efficient expression of therapeutic factors by means of gene transfection is an ideal adjuvant treatment method to promote cell proliferation and angiogenesis.

METHODS

A chimeric recombinant adenoviral vector, Ad5F35ET1-bFGF, was constructed that carried the basic fibroblast growth factor (bFGF) gene and used the endothelin-1 promoter to control the targeted expression of bFGF in endothelial cells and fibroblasts. Thus, the authors established a targeted gene therapy for chronic ischemic wounds.

RESULTS

The chimeric adenovirus Ad5F35ET1-bFGF efficiently infected the endothelin-1-positive endothelial cells and fibroblasts, specifically expressed bFGF, and promoted cell proliferation. In the rabbit wound healing model, the chimeric recombinant adenovirus expressed a high level of bFGF in wound tissues, which continuously promoted angiogenesis and cell proliferation and thus accelerated wound healing.

CONCLUSION

Targeted gene therapy that uses bFGF as a therapeutic gene provides an effective candidate strategy for the treatment of chronic ischemic wounds.

Wound infections and healing: are they contributing factors for carcinogenesis?

The link between inflammation and tumourisation has long been considered as a key event in clinical cancer development. Inflammation and inflammatory diseases can be caused by many factors including infectious agents, altered genetics and various degrees of injuries from simple cuts to traumatic wounds, such as those suffered in battlefield. Improved management of all wound types is critical in protecting affected individuals against the development of tumourisation cues, which may potentially lead to cancer development. There have been numerous studies on the mechanism of inflammation-induced tumourisation. Thus, in this mini review, we summarised evidence demonstrating the potential link between infectious agents and their moonlight proteins, wounding, trauma, overactive repair mechanisms, and carcinogenesis.

New strategies for preoperative skin antisepsis

During the past decades, encouraging progress has been made in the prevention of surgical site infections (SSI). However, as SSI still occur today, strategic prevention measures such as standardized skin antisepsis must be implemented and rigorously promoted. Recent discoveries in skin physiology necessitate the development of novel antiseptic agents and procedures in order to ameliorate their efficacy. In particular, alternate target structures in the skin need to be taken into consideration for the development of the next generation of antiseptics. Recent investigations have shown that a high number of microorganisms are located within and in the close vicinity of the hair follicles. This suggests that these structures are an important reservoir of bacterial growth and activity in human skin. To date, it has not been fully elucidated to what extent conventional liquid antiseptics sufficiently target the hair follicle-related microbial population. Modern technologies such as tissue-tolerable plasma (TTP) have been tested for their potential antiseptic efficiency by reducing the bacterial load in the skin and in the hair follicles. First experiments using liposomes to deliver antiseptics into the hair follicles have been evaluated for their potential clinical application. The present review evaluates these two innovative methods for their efficacy and applicability in preoperative skin antiseptics.

Effect of basic fibroblast growth factor on pluripotent marker expression and colony forming unit capacity of stem cells isolated from human exfoliated deciduous teeth

Human dental pulp of exfoliated deciduous teeth contains the population of cells that exhibited mesenchymal stem cell (MSC) characters. Though, a cell amplification process is indeed required to secure an adequate cell number for such a potential employment. Several publications suggested the alteration of MSCs upon in vitro culture, for example, the decrease in proliferation and the loss of stem cell characters. Here, we investigated an influence of basic fibroblast growth factor (bFGF) on stem cells isolated from human exfoliated deciduous teeth (SHEDs) with respect to cell proliferation, colony forming unit efficiency and stem cell marker expression in both short- and long-term cultures. For short-term bFGF treatment, SHEDs were treated with bFGF for 48 h. While, in long-term bFGF supplementation, SHEDs were maintained in culture and continuous passage upon confluence in medium supplemented with bFGF. Cells at passage (P) 5 and 10 were employed for characterization. Our results showed that short-term bFGF treatment enhanced OCT4, REX1, and NANOG mRNA expression as well as colony forming unit ability. The FGFR inhibitor pretreatment was able to attenuate the influence of bFGF on pluripotent stem cell marker expression, confirming bFGF function. In addition, cells cultured in high passage number had decreased in cell proliferation, colony forming unit capacity, and pluripotent stem cell maker mRNA expression. However, bFGF supplementation in culture medium enhanced both pluripotent stem cell marker expression and colony forming unit capacity in later passage, though the effect was not robust. Together, these results indicate that high passage number may attenuate pluripotent properties of SHEDs and bFGF supplementation could be the beneficial approach to maintain SHEDs' stemness properties.