Vascular Endothelial Growth Factor as an Immediate-Early Activator of Ultraviolet-Induced Skin Injury

Effect of Repeated Low-Dose UVR Exposure on Skin Inflammation Threshold, Skin Biomarkers, and Vitamin D in Healthy Adults

UVR can cause photoaging, skin burns, and skin cancer. The skin counters these effects through photoadaptation, which involves melanin production, skin thickening, and immune responses. This study investigated the effects of repeated, suberythemal low-dose UVR on the skin's inflammation threshold, assessed as minimal erythema dose, across different skin phototypes. In addition, epidermal and stratum corneum thickness, melanin index, erythema index, skin and blood levels of immunological biomarkers, and blood vitamin D3 25(OH) were measured. Over 9 weeks, 31 subjects were exposed to UVR (0.8 standard erythema dose) on the lower back 3 times per week. Results showed a 50% increase in minimal erythema dose, with a stronger effect in lighter phototypes. Increase in minimal erythema dose was paralleled by an increase in erythema index. Melanin index and stratum corneum thickness increased significantly by 12 and 34%, respectively, with melanin having a stronger effect on the minimal erythema dose increase. Vitamin D levels rose by 21%, adjusting for seasonal decline. Immunological markers of T helper 1/T helper 2 response and vascular markers declined, indicating local immunosuppression, although no systemic changes in immunological markers were observed. These findings suggest that even low UVR doses are sufficient to induce photoadaptation. Further research is needed to evaluate the long-term benefits and risks of this exposure.

An Update on the Role of Lymphatic Function in Skin Inflammatory Disorders: A Scoping Review

The lymphatic system is essential in maintaining skin health through coordinated immunological actions. This review explores the relationship between lymphatic function and skin health, as well as the impact of lymphatic dysfunction in the development and progression of inflammatory skin disorders. A systemic search was conducted in the Web of Science, Embase, and Ovid MEDLINE databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. Included studies were peer-reviewed human or animal research published in English from 2014 to 2024, focusing on inflammatory skin disorders, including skin cancer, autoimmune skin diseases, and infectious skin diseases. A total of 1232 citations were identified, with 37 studies meeting the eligibility criteria after assessment and critical appraisal. The review's findings highlight the essential role of lymphatics in maintaining skin health, mitigating inflammatory, infectious, and skin cancer-related processes, and delaying the effects of skin aging. The mechanisms underlying lymphatic function in these processes are complex, with some aspects needing further investigation. However, the evidence indicates that a well-functioning skin lymphatic system, supported by various cytokines, aids in reducing the inflammatory state, reduces inflammation, alleviates lymphedema, and prevents lymphatic stasis, which can increase infection risk. Several studies demonstrated that restoring lymphatic function through improved neutrophil migration and cytokine responses reduces the spread of infectious diseases.

Network Pharmacology and Molecular Dynamics Simulations Reveal the Mechanism of Total Alkaloid Components in Anisodus Tanguticus (Maxim.) Pascher in Treating Inflammation and Pain

This study aimed to elucidate the mechanism that total alkaloids in Anisodus tanguticus (AT)(Maxim.) Pascher played anti-inflammatory and analgesic effects. In this paper, the anti-inflammatory effect in the total alkaloids of AT was confirmed via lipopolysaccharide (LPS)-induced inflammation model in RAW 264.7 cells and the main components of AT were immediately analyzed by UPLC/MS. Disease targets were obtained in GeneCards and DisGeNET. Targets of major compounds were searched in ETCM, TCMSP and other databases. The protein-protein interaction (PPI) network was constructed using STRING database, and Cytoscape was used for core targets screening. GO and KEGG enrichment analysis were performed using Daivid database. Sailvina was used for molecular docking. Molecular dynamics simulation analysis was performed using the Amber 20 program. The results showed that the main components in AT were anisodamine, atropine, fabiatrin, scopolamine, scopoletin and scopolin, possibly exerting anti-inflammatory and analgesic effects through pathways such as EGFR tyrosine kinase inhibitor resistance and IL-17 signaling pathway. Fabiatrin and scopolin could be potential drugs with good anti-inflammatory and analgesic effects.

Biocompatible recombinant type III collagen enhancing skin repair and anti-wrinkle effects

Treating sunburn and other UV-induced skin damage issues remains a significant challenge in the field of dermatology. In this study, we synthesized a highly bioactive recombinant type III collagen (rCol III) to accelerate the healing of UV-damaged skin. The high-purity rCol III demonstrated excellent biocompatibility and bioactivity, significantly promoting the adhesion, proliferation, and migration of HFF-1 cells. In a mouse UV-damage model, Combo evaluations demonstrated that rCol III contributed to restore transepidermal water loss (TEWL) values of UV-damaged skin to normal levels. Histological analysis further confirmed that rCol III substantially accelerated skin repair by enhancing collagen regeneration. Additionally, rCol III facilitated the regeneration of zebrafish tail fin tissue and alleviated shrinkage caused by excessive UV exposure. The biocompatible and bioactive rCol III offers a novel strategy for treating UV-induced skin damage, holding immense potential for applications in skin tissue engineering.

Radiation dermatitis in the hairless mouse model mimics human radiation dermatitis

Over half of all people diagnosed with cancer receive radiation therapy. Moderate to severe radiation dermatitis occurs in most human radiation patients, causing pain, aesthetic distress, and a negative impact on tumor control. No effective prevention or treatment for radiation dermatitis exists. The lack of well-characterized, clinically relevant animal models of human radiation dermatitis contributes to the absence of strategies to mitigate radiation dermatitis. Here, we establish and characterize a hairless SKH-1 mouse model of human radiation dermatitis by correlating temporal stages of clinical and pathological skin injury. We demonstrate that a single ionizing radiation treatment of 30 Gy using 6 MeV electrons induces severe clinical grade 3 peak toxicity at 12 days, defined by marked erythema, desquamation and partial ulceration, with resolution occurring by 25 days. Histopathology reveals that radiation-induced skin injury features temporally unique inflammatory changes. Upregulation of epidermal and dermal TGF-ß1 and COX-2 protein expression occurs at peak dermatitis, with sustained epidermal TGF-ß1 expression beyond resolution. Specific histopathological variables that remain substantially high at peak toxicity and early clinical resolution, including epidermal thickening, hyperkeratosis and dermal fibroplasia/fibrosis, serve as specific measurable parameters for in vivo interventional preclinical studies that seek to mitigate radiation-induced skin injury.

Multifunctional protocatechuic acid-polyacrylic acid hydrogel adhesives for wound dressings

Multifunctional hydrogel adhesives are highly desirable in wound healing applications, yet their preparation often requires complex material system design to achieve. Herein, a straightforward one-pot two-step polymerization method is developed to prepare adhesive hydrogels for wound dressing based on protocatechuic acid (PCA), polyacrylic acid (PAA), and polyamidoamine-epichlorohydrin (PAE), where PCA provides the catechol groups for strong adhesion, PAA serves as the primary polymer matrix, and PAE acts as a bridge connecting PCA and PAA. This design results in a PAA-PAE-PCA hydrogel having a remarkable instant 90-degree peeling interfacial toughness of 431 J m-2 on porcine skin, which is further amplified to 615 J m-2 after 30 minutes. The hydrogel also possesses the desired features for wound dressing, such as self-healing, antioxidant, anti-UV and antibacterial properties, good cytocompatibility, strong adhesion in use and weak adhesion on removal, as well as reversible and wet adhesion. Finally, in vivo data reveal that the PAA-PAE-PCA hydrogels can significantly accelerate wound healing, as evidenced by a noticeable reduction in the wound area and a diminished inflammatory response. Collectively, these results endorse the obtained multifunctional hydrogel as a promising candidate for wound healing and related fields.

Current insights and future perspectives of ultraviolet radiation (UV) exposure: Friends and foes to the skin and beyond the skin

Ultraviolet (UV) radiation is ubiquitous in the environment, which has been classified as an established human carcinogen. As the largest and outermost organ of the body, direct exposure of skin to sunlight or UV radiation can result in sunburn, inflammation, photo-immunosuppression, photoaging and even skin cancers. To date, there are tactics to protect the skin by preventing UV radiation and reducing the amount of UV radiation to the skin. Nevertheless, deciphering the essential regulatory mechanisms may pave the way for therapeutic interventions against UV-induced skin disorders. Additionally, UV light is considered beneficial for specific skin-related conditions in medical UV therapy. Recent evidence indicates that the biological effects of UV exposure extend beyond the skin and include the treatment of inflammatory diseases, solid tumors and certain abnormal behaviors. This review mainly focuses on the effects of UV on the skin. Moreover, novel findings of the biological effects of UV in other organs and systems are also summarized. Nevertheless, the mechanisms through which UV affects the human organism remain to be fully elucidated to achieve a more comprehensive understanding of its biological effects.

The beneficial effect of Sanhuang ointment and its active constituents on experimental hemorrhoids in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Sanhuang ointment (SHO) has been widely used in the traditional Chinese medical system for 1500 years and has efficacy in clearing away heat and dampness, reducing swelling, and alleviating pain. Hemorrhoids will damage the normal physiological function of the body, resulting in obstructed defecation, accompanied by massive hemorrhage and necrosis of tissues and cells, which is easy to breed bacteria and cause infection. SHO can promote lesion healing in hemorrhoid rats, but the pharmacological mechanism underlying this effect remains unknown.

AIM

To evaluate the effect of SHO on experimental hemorrhoids in rats induced by croton oil and glacial acetic acid.

MATERIALS AND METHODS

In this research, the effective components of SHO were analyzed in detail by High performance liquid chromatography (HPLC) and Liquid chromatography/mass spectrometry (LC/MS). Hemorrhoids were induced by 6% balsam and glacial acetic acid respectively in the anorectal region of rats. SHO was administered externally to the anorectal region of rats at doses of 185 mg/g (crude drug/ointment), 370 mg/g (crude drug/ointment) and 740 mg/g (crude drug/ointment) for 11 days. Mayinglong musk hemorrhoids ointment (1 g/kg) and Taining cream (1 g/kg) were used as reference anti hemorrhoids drugs. On the 11th day, hemorrhoids were evaluated by measuring the biochemical parameters of hemorrhoids in rats and the histology of anorectal tissues.

RESULTS

Using high performance liquid chromatography liquid chromatography mass spectrometry, 41 compounds, including phenylpropionic acids and alkaloids, were identified. the fingerprints of 18 common peaks were identified. In Hemorrhoids like rats, acetic acid induced inflammation was inhibited in a dose-dependent manner during SHO treatment. In addition, the detailed experimental results show that SHO can effectively improve hemorrhoids by inhibiting the production of inflammatory cytokines in serum, reversing the down-regulation of vanillin subtype 1 (TRPV1), calcitonin gene related peptide (CGRP) and substance P (SP) levels of pain related genes in anal tissues, and the up regulation of Vascular endothelial growth factor (VEGF) levels of vascular growth related genes.

CONCLUSION

The results showed that SHO could alleviate the edema caused by the exudation of anorectal tissue fluid in rats by anti-inflammatory effect and reducing the Vascular permeability of rats. The study validates the traditional use of SHO in the treatment of hemorrhoids and demonstrates its anti-hemorrhoidal potential.

Luteolin photo-protects zebrafish from environmental stressor ultraviolet radiation (UVB)

Ultraviolet B wavelength ray radiation (UVB) is an environmental stressor with detrimental effects to the aquatic and human systems but also enhances adverse effects when combined with several other environmental factors such as temperature and pollution. UV rays induce cellular oxidative damage and impair motility. This study aimed to examine the photo-protective activity of flavonoid luteolin against UV-B irradiation-induced oxidative stress and cellular damage using zebrafish. An in-vivo photoaging model was established using UV-B irradiation in zebrafish larvae exposed to 100 mJ/cm2. Data demonstrated that UV-B irradiation of swimming water enhanced production of ROS and superoxide anions as well as depleted total glutathione levels in zebrafish larvae. UV-B irradiation also triggered cellular damage and membrane rupture in zebra fish. Further, 100 mJ/cm2 of UV-B radiation exposure to adult-wild type zebrafish co-exposed with intraperitoneally (ip) injected luteolin upregulated the local neuroendocrine axes by activating vascular endothelial growth factor (VEGF) and elevating levels of pro-inflammatory cytokines IL-1β and TNF-α. Histologically, UV-B irradiation induced skin lesions and locomotory defects with clumping and degeneration of brain glial cells. However, luteolin effectively inhibited the excess production of reactive oxygen species (ROS) and decreased superoxide anion levels induced by UV-B irradiation. Luteolin restored the depleted glutathione levels. In addition, luteolin blocked apoptosis and lipidperoxidation. Luteolin protected adult zebrafish by downregulating the pro-inflammatory cytokine protein expression levels and diminishing VEGF activation. Luteolin also alleviated locomotory defects by inhibiting activation of microglia and inflammatory responses by preventing accumulation of glial cells and vacuolation. Data demonstrate that luteolin may protect zebrafish from UV-B-induced photodamage through DNA-protective, antioxidant and anti-inflammatory responses.

Expression of angiogenic and lymphangiogenic genes in primary cutaneous melanoma: relationship with angiolymphatic invasion and disease-free survival

Melanoma is one of the most common cancers in the world. The main routes of tumor progression are related to angiogenesis and lymphangiogenesis. These routes can occur by local invasion, which is called angiolymphatic invasion (ALI). In this study, we assess gene expression of relevant biomarkers of angiogenesis and lymphangiogenesis in 80 FFPE melanoma samples to determine a molecular profile that correlates with ALI, tumor progression, and disease-free survival. The results were enhanced by a posttranscriptional analysis by an immunofluorescence assay. Three SNPs in the VEGFR-2 gene were genotyped in 237 malignant melanoma (MM) blood DNA samples by qPCR. A significant correlation was found for LYVE -1 and ALI, qualitative ( P  = 0.017) and quantitative ( P  = 0.005). An increased expression of protein LIVE-1 in ALI samples supported these results ( P  = 0.032). VEGFR2 was lower in patients who showed disease progression ( P  = 0.005) and protein VEGFR2 posttranscriptional expression decreased ( P  = 0.016). DFS curves showed differences ( P  = 0.023) for VEGFR2 expression detected versus the absence of VEGFR2 expression. No significant influence on DFS was detected for the remaining analyzed genes. Cox regression analysis suggested that VEGFR2 expression has a protective role (HR = 0.728; 95% CI = 0.552-0.962; P  = 0.025) on disease progression. No significant association was found between any of the studied SNPs of VEGFR2 and DFS or progression rate. Our main results suggest that LYVE-1 gene expression is closely related to ALI; the relationship with the development of metastases in MM deserves further studies. Low expression of VEGFR2 was associated with disease progression and the expression of VEGFR2 correlates with an increased DFS.

Engineered NF-κB siRNA-encapsulating exosomes as a modality for therapy of skin lesions

Introduction

Despite the protection and management of skin has been paid more and more attention, effective countermeasures are still lacking for patients suffering from UV or chemotherapy with damaged skin. Recently, gene therapy by small interfering RNA (siRNA) has emerged as a new therapeutic strategy for skin lesions. However, siRNA therapy has not been applied to skin therapy due to lack of effective delivery vector.

Methods

Here, we develop a synthetic biology strategy that integrates the exosomes with artificial genetic circuits to reprogram the adipose mesenchymal stem cell to express and assemble siRNAs into exosomes and facilitate in vivo delivery siRNAs for therapy of mouse models of skin lesions.

Results

Particularly, siRNA enriched exosomes (si-ADMSC-EXOs) could be directly taken up by the skin cells to inhibit the expression of skin injury related genes. When mice with skin lesions were smeared with si-ADMSC-EXOs, the repair of lesioned skin became faster and the expression of inflammatory cytokines were decreased.

Discussion

Overall, this study establishes a feasible therapeutic strategy for skin injury, which may offer an alternative to conventional biological therapies requiring two or more independent compounds.

Clinical Efficacy of Medical Dextrose Tincture Liquid in the Treatment of Facial Photoaging

INTRODUCTION

Exogenous aging mainly refers to photo-aging, which is caused by environmental factors including ultraviolet exposure. Dextran is a homopolysaccharide composed of glucose as monosaccharide, and glucose units are connected by glycosidic bonds.

OBJECTIVES

The purpose of this study was to explore the clinical efficacy of medical dextrose tincture liquid (medical dextrose tincture) in the treatment of facial photoaging.

METHODS

Thirty-four volunteers were included in the randomized double-blind study. According to the random number table method, the subjects were randomized into control and treatment groups. The subjects in the control and treatment groups were treated with medical hyaluronic acid gel and medical dextrose tincture, respectively. They received mesotherapy therapy three times with an interval of 28 days between treatments. Video image acquisition was performed before treatment and 28 days after treatment. Skin moisture content, glossiness, heme content, collagen density, and elasticity were tested. The subjective evaluations of subjects and doctors before and after treatment were compared.

RESULTS

Compared with the pre-treatment baseline, medical dextran tincture significantly increased skin moisture retention, skin gloss, and skin collagen density (p<0.001). Additionally, the skin retraction time was significantly reduced, and the skin retraction time was also markedly decreased after treatment with medical dextran tincture (p<0.001). The effects of medical dextran tincture were more significant in comparison with medical hyaluronic acid gel (p<0.05). The subjective evaluation results of doctors showed that after 84 days of treatment, the overall skin photoaging score was significantly reduced (p<0.001). The subjective evaluation results of volunteers showed that the various skin problems of more than 50% of volunteers were improved after treatment.

CONCLUSION

Medical dextran tincture has obvious effects of moisturizing, increasing luster, improving skin redness, increasing skin collagen content and enhancing skin elasticity.

Role of matrix metalloproteinase in wound healing

Matrix metalloproteinases (MMPs) are a group of endopeptidases that play a vital role in the restoration of damaged skin. Through mediating various cellular events such as angiogenesis and vasodilation, MMPs are very crucial for the mechanism of wound healing. These enzymes are endopeptidases that are reliant on zinc which are concealed through the extracellular matrix (ECM). MMPs have different targets in different phases of wound healing through which they are capable of promoting timely healing in the body. This review discusses all the possible role of MMPs and their inhibitors that are involved during every step of the wound healing process. This review highlights the latest advances in the respective field about the regulation and mediation of MMPs in human skin and how these studies can be applied to other branches of medical sciences as well. Published papers were searched via MEDLINE, PubMed and MDPI from the available peer reviewed journals. Research done in the past suggests that active MMPs are involved in the healing progression of the wounds or they have a positive effect towards healing of wounds. Present studies in the relative field will further enhance the knowledge about enzymes working along with their inhibitors. These studies will help in a way to resolve some of the parameters that are necessary for modulating them either positively or negatively.

Inhibition of Fibroblast Growth Factor Receptor Attenuates Ultraviolet B-Induced Skin Carcinogenesis

Altered FGFR signaling has been shown to play a role in a number of cancers. However, the role of FGFR signaling in the development and progression of ultraviolet B-induced (UVB) induced cutaneous squamous cell carcinoma (cSCC) remains unclear. In the current study, the effect of UVB radiation on FGFR activation and its downstream signaling in mouse skin epidermis was examined. In addition, the impact of FGFR inhibition on UVB-induced signaling and skin carcinogenesis was also investigated. Exposure of mouse dorsal skin to UVB significantly increased phosphorylation of FGFRs in the epidermis as well as activation of downstream signaling pathways, including AKT/mTOR, STATs and MAPK. Topical application of the pan-FGFR inhibitor AZD4547 to mouse skin prior to exposure to UVB significantly inhibited FGFR phosphorylation as well as mTORC1, STAT3 and MAPK activation (i.e., phosphorylation). Moreover, AZD4547 pretreatment significantly inhibited UVB-induced epidermal hyperplasia and hyperproliferation and reduced infiltration of mast cells and macrophages into the dermis. AZD4547 treatment also significantly inhibited mRNA expression of inflammatory genes in the epidermis. Finally, mice treated topically with AZD4547 prior to UVB exposure showed decreased cSCC incidence and increased survival rate. Collectively, the current data supports the hypothesis that inhibition of FGFR in epidermis may provide a new strategy to prevent and/or treat UVB-induced cSCC.