Skin aging: the dermal perspective

Comprehensive evaluation of the efficacy and safety of a new multi-component anti-aging topical eye cream

BACKGROUND

The delicate periorbital region is susceptible to skin dehydration, wrinkles, and loss of elasticity. Thus, targeted and effective anti-aging interventions are necessary for the periorbital area.

AIM

To evaluate the efficacy and safety of a new anti-aging eye cream formulated with the active complex (Yeast/rice fermentation filtrate, N-acetylneuraminic acid, palmityl tripeptide-1, and palmitoyl tetrapeptide-7).

METHODS

The cell viability and expressions of key extracellular matrix (ECM) components of the active complex were evaluated using a human skin fibroblast model. In the 12-week clinical trial, skin hydration, elasticity, facial photographs, and collagen density following eye cream application were assessed using Corneometer, Cutometer, VISIA, and ultrasound device, respectively. Dermatologists and participants evaluated clinical efficacy and safety at baseline, and after 4, 8, and 12 weeks.

RESULTS

PCR and immunofluorescent analyses revealed that the active complex significantly stimulated fibroblast proliferation (p < 0.05) and markedly promote the synthesis of collagen and elastin. Clinical findings exhibited a substantial enhancement in skin hydration (28.12%), elasticity (18.81%), and collagen production (54.99%) following 12 weeks of eye cream application. Dermatological evaluations and participants' assessments reported a significant improvement in skin moisture, roughness, elasticity, as well as fine lines and wrinkles by week 8.

CONCLUSION

The new anti-aging eye cream, enriched with the active complex, demonstrates comprehensive rejuvenating effects, effectively addressing aging concerns in the periorbital area, coupled with a high safety profile.

Knowledge, Attitude, Reception, and Preventive Practices Towards Skin Photoaging Among the General Population in Jazan, Saudi Arabia

Introduction Skin photoaging is caused by prolonged exposure to sunlight, particularly ultraviolet rays (UV). High cumulative levels of UV radiation may cause burning, photoallergic or phototoxic reactions, pigmentary changes, photoaging, and even immunosuppression and skin cancers. Therefore, this study aims to assess knowledge, attitude, reception, and preventive practices towards skin photoaging among the Jazan general population in Saudi Arabia and its determinants. Methods A descriptive cross-sectional study was conducted among the general population of Jazan, Saudi Arabia, who were aged 18 years and above and agreed to participate in the study. The calculated minimum sample size was 385. An online, semi-structured, self-administered questionnaire was distributed conveniently in Google Forms through social media platforms. It included four sections: The first section was about sociodemographic characteristics. The second section assessed the smoking, exercise, and healthy diet behavior of participants and the use of sunscreen. The third section assessed the knowledge regarding the photoaging process and its preventive measures utilization using three-point Likert scale questions. The fourth section assessed attitudes towards the photoaging process and its preventive measures through three-point Likert scales. Results The study included 452, of which 243 (53.76%) were aged 18-30 years, 258 (57.08%) were females, and 272 (60.18%) had white skin color. Approximately 417 (92.26%) were nonsmokers. Sixty-eight percent (372) spent 1-3 hours in the sun. Social media was the primary source of information on photoaging 81 (17.92%). Around 234 (51.77%) defined photoaging correctly. Regarding sunscreen usage, 58 (12.83%) always use sunscreen, and 177 (39.16%) never use it. However, 191 (42.26%) recognized the correct sunscreen application. Approximately 233 (51.5%) and 240 (53.1%) of respondents had fair knowledge and a positive attitude regarding photoaging and sunscreen use. Being female, pursuing university and postgraduate education, and taking information on photoaging from a physician were linked to a higher knowledge of photoaging (p<0.05). Participants who never use sunscreen had lower knowledge than those who always use it (p<0.001). None of the demographic factors was associated with the attitude towards sunscreen use (p>0.05). Conclusion There is a substantial gap in knowledge and preventive practices related to skin photoaging among the Jazan general population in Saudi Arabia. Gender, education level, and information sources influence knowledge levels. Targeted educational interventions are needed to enhance awareness and promote healthier practices, particularly sun exposure and photoaging prevention.

Diagnostic rate estimation from Medicare records: Dependence on claim numbers and latent clinical features

OBJECTIVE

International Classification of Disorders version 10 (ICD-10) codes contribute heavily to healthcare data. Medicare claims and other data-sources are used to constitute study populations and appraise healthcare processes. How variability in claims-per-beneficiary impacts diagnostic determinations is inadequately understood. The objective of this study is so assess distributional properties of Medicare claims, and examine claim rates impact on code utilization and rate determinations.

METHODS

The study population was Medicare beneficiaries aged 75-79.99 with claim(s) in the 5% standard analytical Carrier and Outpatient files, alive and participating in Medicare part B for all 12 months of 2017. Medicare beneficiary files were processed to create records containing all ICD-10 codes specified, key demographics, Part B and vital status, and the total claims for each 2017 beneficiary. Claim number cohorts were characterized.

RESULTS

Beneficiaries meeting inclusion criteria totaled 221,625, these having 7,617,503 claims; 96.4% had between 1 and 120 claims. Median claims were 24 for males (females 25); modal claims were 11 (13). Average distinct codes per beneficiary increased with claims number. The assignment of ICD-10 codes, i.e., 'diagnostic rate estimates' (DRE), increased as claim numbers increased for most codes among those most commonly utilized. For some conditions, mostly benign and age-related, DREs plateaued as claim numbers increased. For other conditions, typically associated with clinical acuity, e.g., chest pain, DREs increased steeply with claims.

CONCLUSIONS

Older adult Medicare beneficiaries aged 75-80 exhibited varying claims activity over the course of a year. Although DRE dependence on claim numbers varies across ICD-10 codes, rate estimates are higher for beneficiaries with claim numbers above the median.

Chitosan-Coated Niosomes Loaded with Ellagic Acid Present Antiaging Activity in a Skin Cell Line

The polyphenol compound ellagic acid (EA) extracted from pomegranate has potential bioactivity against different types of chronic diseases. Skin aging is a long-term physiological process caused by many environmental factors, the most important of which is exposure to sun ultraviolet (UV) radiation. UV-induced chronic photodamage of the skin results in extrinsic aging. This study aimed to evaluate the photoprotective effects of EA on the human fibroblast skin cell line HFB4 and investigate its capacity to protect collagen from UV-induced deterioration. EA was encapsulated into chitosan-coated niosomes to reduce the skin aging effect of UV radiation in vitro. The tested formulations (niosomes loaded with EA and chitosan-coated niosomes loaded with EA) were characterized using transmission electron microscopy, dynamic light scattering, and scanning electron microscopy. Furthermore, the in vitro release of EA was determined. The HFB4 cell line samples were split into five groups: control, UV, UV-EA, UV-NIO-EA, and UV-CS-NIO-EA. UV irradiation was applied to the cell line groups via a UV-emitting lamp for 1 h, and then cell viability was measured for each group. The expression of genes implicated in skin aging (Co1A1, TERT, Timp3, and MMP3) was also assessed to quantify the impact of the loaded EA. The findings showed that EA-loaded chitosan-coated niosomes improved cell survival, upregulated Col1A1, TERT, and Timp3 genes, and downregulated MMP3. Thus, nanoparticles encapsulating EA are potent antioxidants that can preserve collagen levels and slow down the aging process in human skin.

The role of sirtuins in dermal fibroblast function

The sirtuins are a family of seven proteins that perform a variety of dermatological functions and help maintain both the structure and function of the skin. More specifically, the sirtuins have been shown to be altered in multiple dermal cell types including dermal fibroblasts. The functions of dermal fibroblasts are extensive, and include playing a significant role in wound healing as well as helping to maintain the integrity of the skin. As dermal fibroblasts age, they can undergo a state of permanent cell cycle arrest, known as cellular senescence. This senescent process can occur as a result of various stressors, including oxidative stress, ultraviolet radiation -induced stress, and replicative stress. In recent years, there has been a growing interest in both enhancing the cutaneous fibroblast’s ability to facilitate wound healing and altering fibroblast cellular senescence. Thus, in this review, we examine the relationship between sirtuin signaling and dermal fibroblasts to understand how this family of proteins may modulate skin conditions ranging from the wound healing process to photocarcinogenesis associated with fibroblast senescence. Additionally, we offer supporting data from experiments examining the relationship between fibroblast senescence and sirtuin levels in an oxidative stress model indicating that senescent dermal fibroblasts exhibit diminished sirtuin levels. Furthermore, we survey the research on the role of sirtuins in specific dermatological disease states that where dermal fibroblast function has been implicated. Finally, we conclude with outlining potential clinical applications of sirtuins in dermatology. In sum, we find that the literature on the involvement of sirtuins in dermal fibroblasts is limited, with research still in its early stages. Nevertheless, intriguing preliminary findings merit additional investigation into the clinical implications of sirtuins in dermatology.

Differences in clinical characteristics of rosacea across age groups: A retrospective study of 840 female patients

BACKGROUND

Aging remains a common influencing factor for many diseases. Previous studies have shown that age is significantly associated with rosacea among female cases and that the incidence of rosacea increases with age. However, previous studies did not specifically analyze the clinical characteristics of different age groups.

OBJECTIVE

This study aimed to analyze and compare the clinical characteristics of female patients of rosacea among different age groups.

METHODS

We conducted a retrospective study of 840 female rosacea subjects and compared cutaneous features, aggravating factors, systemic diseases, and psychological states across age groups. The patients were divided into three groups according to their age at diagnosis: ≤30 years，31-44 years，and ≥45 years.

RESULTS

In our study, the mean age of subjects was 35.9 ± 10.23 years. The common symptoms included telangiectasia (82.6%), persistent erythema (82.0%), burning/stinging sensation (89.3%), dry sensation (74.0%), and pruritis (41.9%). Hot temperature (89.9%), emotional changes (67.3%), spicy food (55.6%), and sun exposure (50.7%) were the common aggravating factors. Some patients had comorbidities of systemic disorders (20.4%). Of the patients, 48.8% presented with anxiety and 35.2% with depression. The clinical characteristics were found to be significantly different among the different age groups. Middle-aged and older patients (≥45 years) were more likely to have more serious persistent erythema and telangiectasia. And these patients were relatively less affected by some of the influencing factors and had more systemic diseases of the digestive system, endocrine metabolic system, and cardiovascular system (p < 0.05).

CONCLUSION

We revealed the impact of age on the characteristics of rosacea, which indicated that the clinical features of rosacea are more complex and more difficult to treat in females over the age of 45.

3D Printed Hollow Microneedles for Treating Skin Wrinkles Using Different Anti-Wrinkle Agents: A Possible Futuristic Approach

Skin wrinkles are an inevitable phenomenon that is brought about by aging due to the degradation of scleroprotein fibers and significant collagen reduction, which is the fundamental basis of anti-wrinkle technology in use today. Conventional treatments such as lasering and Botulinum toxin have some drawbacks including allergic skin reactions, cumbersome treatment procedures, and inefficient penetration of the anti-wrinkle products into the skin due to the high resistance of stratum corneum. Bearing this in mind, the cosmetic industry has exploited the patient-compliant technology of microneedles (MNs) to treat skin wrinkles, developing several products based on solid and dissolvable MNs incorporated with antiwrinkle formulations. However, drug administration via these MNs is limited by the high molecular weight of the drugs. Hollow MNs (HMNs) can deliver a wider array of active agents, but that is a relatively unexplored area in the context of antiwrinkle technology. To address this gap, we discuss the possibility of bioinspired 3D printed HMNs in treating skin wrinkles in this paper. We compare the previous and current anti-wrinkling treatment options, as well as the techniques and challenges involved with its manufacture and commercialization.

The Human Dermis as a Target of Nanoparticles for Treating Skin Conditions

Skin has a preventive role against any damage raised by harmful microorganisms and physical and chemical assaults from the external environment that could affect the body's internal organs. Dermis represents the main section of the skin, and its contribution to skin physiology is critical due to its diverse cellularity, vasculature, and release of molecular mediators involved in the extracellular matrix maintenance and modulation of the immune response. Skin structure and complexity limit the transport of substances, promoting the study of different types of nanoparticles that penetrate the skin layers under different mechanisms intended for skin illness treatments and dermo-cosmetic applications. In this work, we present a detailed morphological description of the dermis in terms of its structures and resident cells. Furthermore, we analyze the role of the dermis in regulating skin homeostasis and its alterations in pathophysiological conditions, highlighting its potential as a therapeutic target. Additionally, we describe the use of nanoparticles for skin illness treatments focused on dermis release and promote the use of metal-organic frameworks (MOFs) as an integrative strategy for skin treatments.

Aging and Wound Healing of the Skin: A Review of Clinical and Pathophysiological Hallmarks

Aging is a universal process that can cause diminished function of organs and various diseases. The most striking consequences of aging can be seen visibly on the skin, which acts as a barrier against various external insults. Aging of the skin consists of intrinsic and extrinsic processes that work in concert and influence each other. Intrinsic aging involves biochemical degenerative processes that gradually takes place with age. Extrinsic aging are biochemical processes driven by external influences that lead to aging. There are significant morphological changes at all levels in aged skin that have a profound effect on the characteristics of the skin. Even though skin is subjected to damage by external insults, it is equipped with a healing capability in order to restore its normal structure and function. However, aging has a significant impact on the skin's healing function by prolonging the inflammatory phase and increasing the production of reactive oxygen species (ROS). This shifts the healing process towards having more protein degradation, which can lead to chronic wound healing with an abundance of complications.

2-O-β-d-Glucopyranosyl-4,6-dihydroxybenzaldehyde Isolated from Morus alba (Mulberry) Fruits Suppresses Damage by Regulating Oxidative and Inflammatory Responses in TNF-α-Induced Human Dermal Fibroblasts

Human skin is composed of three layers, of which the dermis is composed of an extracellular matrix (ECM) comprising collagen, elastin, and other proteins. These proteins are reduced due to skin aging caused by intrinsic and extrinsic factors. Among various internal and external factors related to aging, ultraviolet (UV) radiation is the main cause of photoaging of the skin. UV radiation stimulates DNA damage, reactive oxygen species (ROS) generation, and pro-inflammatory cytokine production such as tumor necrosis factor-alpha (TNF-α), and promotes ECM degradation. Stimulation with ROS and TNF-α upregulates mitogen-activated protein kinases (MAPKs), nuclear factor kappa B (NF-κB), and activator protein 1 (AP-1) transcription factors that induce the expression of the collagenase matrix metalloproteinase-1 (MMP-1). Moreover, TNF-α induces intracellular ROS production and several molecular pathways. Skin aging progresses through various processes and can be prevented through ROS generation and TNF-α inhibition. In our previous study, 2-O-β-d-glucopyranosyl-4,6-dihydroxybenzaldehyde (GDHBA) was isolated from the Morus alba (mulberry) fruits and its inhibitory effect on MMP-1 secretion was revealed. In this study, we focused on the effect of GDHBA on TNF-α-induced human dermal fibroblasts (HDFs). GDHBA (50 μM) inhibited ROS generation (18.8%) and decreased NO (58.4%) and PGE₂ levels (53.8%), significantly. Moreover, it decreased MMP-1 secretion (55.3%) and increased pro-collagen type I secretion (207.7%). GDHBA (50 μM) decreased the expression of different MAPKs as per western blotting; p-38: 35.9%; ERK: 47.9%; JNK: 49.5%; c-Jun: 32.1%; NF-κB: 55.9%; and cyclooxygenase-2 (COX-2): 31%. This study elucidated a novel role of GDHBA in protecting against skin inflammation and damage through external stimuli, such as UV radiation.

Study on the effect of Pogostemon cablin Benth on skin aging based on network pharmacology

BACKGROUND

At present, there is still little research on the anti-aging effect of Pogostemon cablin Benth (PCB) on human skin. In this paper, the mechanism of anti-aging effect of PCB on human skin was studied by using network pharmacology and molecular docking methods.

OBJECTIVE

To analyze the pharmacological mechanism of PCB in the treatment of skin aging, so as to provide reference for new drug development and clinical application.

METHODS

Active ingredients and related targets of PCB and skin aging-related disease targets are obtained through public databases, and the "drug-disease-target" and protein-protein interaction (PPI) network diagrams were constructed with the help of software to screen the core targets; Then GO analysis and KEGG pathway analysis were performed on the target; Finally, the molecular docking between the components and the targets were verified.

RESULTS

After screening, 112 intersection targets of active compounds of skin aging and PCB were obtained. Through GO and KEGG enrichment analysis, it is found that these biological processes mainly focus on epithelial cell proliferation, aging, growth factors, longevity regulation pathway, cancer pathway, AGE-RAGE signal pathway, PI3K Akt signal pathway and IL-17 signal pathway. The molecular docking results showed that quercetin, apigenin, irisnepalensis isoflavone, 3,23-dihydroxy-12-oleorene-28-oleic acid, 5-hydroxy-7,4'- dimethoxyflavone and other major compounds were connected with TP53, JUN, HSP90AAL, AKT1 and MAPK1 through hydrogen bonds, and there was high binding energy between them.

CONCLUSION

Through multi-target prediction and molecular docking verification, it shows that PCB provides a strong effect in the treatment of skin aging, which provides a reference for its further research.

Human placental extract activates a wide array of gene expressions related to skin functions

As skin aging is one of the most common dermatological concerns in recent years, scientific research has promoted treatment strategies aimed at preventing or reversing skin aging. Breakdown of the extracellular matrix (ECM), such as collagen and elastin fibers, in the skin results in decreased skin elasticity and tension. Cutaneous cells, especially fibroblasts in the dermis layer of the skin, mainly produce ECM proteins. Although clinical studies have demonstrated that placental extract (PE) has positive effects on skin health, the molecular mechanisms by which PE acts against skin aging are still largely unknown. In this study, we performed RNA-sequence analysis to investigate whether human PE (HPE) alters ECM-related gene expression in normal human dermal fibroblast (NHDF) cells. Gene ontology analysis showed that genes related to extracellular matrix/structure organization, such as COL1A1, COL5A3, ELN, and HAS2 were highly enriched, and most of these genes were upregulated. We further confirmed that the HPE increased the type I collagen, proteoglycan versican, elastin, and hyaluronan levels in NHDF cells. Our results demonstrate that HPE activates global ECM-related gene expression in NHDF cells, which accounts for the clinical evidence that the HPE affects skin aging.

Cancer-Associated Fibroblasts Influence the Biological Properties of Malignant Tumours via Paracrine Secretion and Exosome Production

Cancer-associated fibroblasts (CAFs) are an essential component of the tumour microenvironment. They represent a heterogeneous group of cells that are under the control of cancer cells and can reversely influence the cancer cell population. They affect the cancer cell differentiation status, and the migration and formation of metastases. This is achieved through the production of the extracellular matrix and numerous bioactive factors. IL-6 seems to play the central role in the communication of noncancerous and cancer cells in the tumour. This review outlines the role of exosomes in cancer cells and cancer-associated fibroblasts. Available data on the exosomal cargo, which can significantly intensify interactions in the tumour, are summarised. The role of exosomes as mediators of the dialogue between cancer cells and cancer-associated fibroblasts is discussed together with their therapeutic relevance. The functional unity of the paracrine- and exosome-mediated communication of cancer cells with the tumour microenvironment represented by CAFs is worthy of attention.

Anti-ageing peptides and proteins for topical applications: a review

Skin ageing is a cumulative result of oxidative stress, predominantly caused by reactive oxygen species (ROS). Respiration, pollutants, toxins, or ultraviolet A (UVA) irradiation produce ROS with 80% of skin damage attributed to UVA irradiation. Anti-ageing peptides and proteins are considered valuable compounds for removing ROS to prevent skin ageing and maintenance of skin health. In this review, skin ageing theory has been illustrated with a focus on the mechanism and relationship with anti-ageing peptides and proteins. The effects, classification, and transport pathways of anti-ageing peptides and proteins across skin are summarized and discussed. Over the last decade, several novel formulations and advanced strategies have been developed to overcome the challenges in the dermal delivery of proteins and peptides for skin ageing. This article also provides an in-depth review of the latest advancements in the dermal delivery of anti-ageing proteins and peptides. Based on these studies, this review prospected several semi-solid dosage forms to achieve topical applicability for anti-ageing peptides and proteins.

How good is the evidence that cellular senescence causes skin ageing?

Skin is the largest organ of the body with important protective functions, which become compromised with time due to both intrinsic and extrinsic ageing processes. Cellular senescence is the primary ageing process at cell level, associated with loss of proliferative capacity, mitochondrial dysfunction and significantly altered patterns of expression and secretion of bioactive molecules. Intervention experiments have proven cell senescence as a relevant cause of ageing in many organs. In case of skin, accumulation of senescence in all major compartments with ageing is well documented and might be responsible for most, if not all, the molecular changes observed during ageing. Incorporation of senescent cells into in-vitro skin models (specifically 3D full thickness models) recapitulates changes typically associated with skin ageing. However, crucial evidence is still missing. A beneficial effect of senescent cell ablation on skin ageing has so far only been shown following rather unspecific interventions or in transgenic mouse models. We conclude that evidence for cellular senescence as a relevant cause of intrinsic skin ageing is highly suggestive but not yet completely conclusive.

An Insight into Biomolecules for the Treatment of Skin Infectious Diseases

In assigning priorities, skin infectious diseases are frequently classified as minor when compared to infectious diseases of high mortality rates, such as tuberculosis or HIV. However, skin infections are amongst the most common and prevalent diseases worldwide. Elderly individuals present an increased susceptibility to skin infections, which may develop atypical signs and symptoms or even complicate pre-existing chronic disorders. When the skin fails to correct or inhibit the action of certain pathogenic microorganisms, biomolecules endowed with antimicrobial features are frequently administered topically or systemically to assist or treat such conditions. (1) Antibiotics, (2) antimicrobial peptides, or (3) natural extracts display important features that can actively inhibit the propagation of these pathogens and prevent the evolution of infectious diseases. This review highlights the properties and mechanisms of action of these biomolecules, emphasizing their effects on the most prevalent and difficult to treat skin infections caused by pathogenic bacteria, fungi, and viruses. The versatility of biomolecules’ actions, their symbiotic effects with skin cells and other inherent antimicrobial components, and their target-directed signatures are also explored here.

Differences in the response in the dermis of the tails of young and old SD rats to treatment with bipolar RF

BACKGROUND

The passing of the years is marked by intrinsic (chronological) and extrinsic aging, caused by photoaging, which is characterized by a decrease in collagen and the deposition of abnormal elastic fibers in the dermis. The use of bipolar radiofrequency (RF) increases fibroblast proliferation and differentiation, accompanied by collagen synthesis and a subsequent increase in connective tissue, and it is not known whether the biological effects of this type of radiofrequency on the dermis are similar regardless of the age of the individual or whether such effects are altered by the aging process itself.

AIMS

The objective was to perform a histological study of the changes in the tail dermis of young and old rats after submitting them to bipolar RF, to determine cell proliferation and volume of connective tissue.

METHODS

One part of the rat tail was fixed in formol and processed for light microscopy and another part processed for electron microscopy.

RESULTS

The number of fibroblasts/unit area and cells positive to nuclear proliferation antigen was higher in young animals. Significant differences were observed regarding expression of HSP-47 protein, and the value was always lower in old rats. No significant differences were observed in the percentage of connective tissue. No histological alterations were observed in any rats.

CONCLUSION

Treatment with RF increased the number of fibroblasts located in the connective tissue of the young rats. In addition, the effect of a single treatment on the population of fibroblasts in young animals was sufficient to activate the synthesis of new collagen.

The effect of Q-switched 1064-nm dymium-doped yttrium aluminum garnet laser on the skin barrier and collagen synthesis through miR-24-3p

Due to the increase of the world’s population aging, how to restore youthfulness to the skin has attracted much attention. It is well known that collagen synthesis and changes in skin barrier play an important role in the process of skin aging. However, whether Q-switched 1064-nm Nd:YAG laser (1064-QSNYL) determines the involvement of miRNAs in skin collagen synthesis and skin barrier changes remains to be elucidated. Upstream miRNAs of p38 molecular pathway have been predicted by bioinformatic database and the relationship between miRNAs and p38 verified by dual-luciferase reporter gene and Western blotting. RT-qPCR analysis detected the expression of miR-24-3p and mRNA for collagen and skin barrier–related molecules, such as keratin 10 (K10), filaggrin, and Aquaporin 4 (APQ4), in mice back skin and in the keratinocyte cell line HaCaT. Western blotting and immunofluorescence (IF) have been used to detect collagen expression and to localize, as well as quantify K10, filaggrin, and APQ4, respectively. In this study, we show that p38 is the main target gene of miRNA-24-3p, and laser irradiation at 1.5 J/cm² inhibits miR-24-3p expression. Irradiation treatment upregulates the moisture, elasticity, hydroxyproline, and superoxide dismutase content of mice skin, as well as inhibits trans-epidermal water loss. Irradiation also increases collagen, K10, filaggrin, and APQ4 in both mice skin and HaCaT cells. Interestingly, we found that miR-24-3p overexpression inhibits the effect of irradiation on collagen synthesis and skin barrier. We show for the first time that 1064-QSNYL promotes collagen synthesis and protective effects on skin barrier by downregulating miR-24-3p.

Single-Cell RNA Sequencing Unravels Heterogeneity of the Stromal Niche in Cutaneous Melanoma Heterogeneous Spheroids

Heterogeneous spheroids have recently acquired a prominent position in melanoma research because they incorporate microenvironmental cues relevant for melanoma. In this study, we focused on the analysis of microenvironmental factors introduced in melanoma heterogeneous spheroids by different dermal fibroblasts. We aimed to map the fibroblast diversity resulting from previously acquired damage caused by exposure to extrinsic and intrinsic stimuli. To construct heterogeneous melanoma spheroids, we used normal dermal fibroblasts from the sun-protected skin of a juvenile donor. We compared them to the fibroblasts from the sun-exposed photodamaged skin of an adult donor. Further, we analysed the spheroids by single-cell RNA sequencing. To validate transcriptional data, we also compared the immunohistochemical analysis of heterogeneous spheroids to melanoma biopsies. We have distinguished three functional clusters in primary human fibroblasts from melanoma spheroids. These clusters differed in the expression of (a) extracellular matrix-related genes, (b) pro-inflammatory factors, and (c) TGFβ signalling superfamily. We observed a broader deregulation of gene transcription in previously photodamaged cells. We have confirmed that pro-inflammatory cytokine IL-6 significantly enhances melanoma invasion to the extracellular matrix in our model. This supports the opinion that the aspects of ageing are essential for reliable melanoma 3D modelling in vitro.

Interleukin-6: Molecule in the Intersection of Cancer, Ageing and COVID-19

Interleukin-6 (IL-6) is a cytokine with multifaceted effects playing a remarkable role in the initiation of the immune response. The increased level of this cytokine in the elderly seems to be associated with the chronic inflammatory setting of the microenvironment in aged individuals. IL-6 also represents one of the main signals in communication between cancer cells and their non-malignant neighbours within the tumour niche. IL-6 also participates in the development of a premetastatic niche and in the adjustment of the metabolism in terminal-stage patients suffering from a malignant disease. IL-6 is a fundamental factor of the cytokine storm in patients with severe COVID-19, where it is responsible for the fatal outcome of the disease. A better understanding of the role of IL-6 under physiological as well as pathological conditions and the preparation of new strategies for the therapeutic control of the IL-6 axis may help to manage the problems associated with the elderly, cancer, and serious viral infections.

Cutaneous melanoma dissemination is dependent on the malignant cell properties and factors of intercellular crosstalk in the cancer microenvironment (Review)

The incidence of cutaneous malignant melanoma has been steadily increasing worldwide for several decades. This phenomenon seems to follow the trend observed in many types of malignancies caused by multiple significant factors, including ageing. Despite the progress in cutaneous malignant melanoma therapeutic options, the curability of advanced disease after metastasis represents a serious challenge for further research. In this review, we summarise data on the microenvironment of cutaneous malignant melanoma with emphasis on intercellular signalling during the disease progression. Malignant melanocytes with features of neural crest stem cells interact with non‑malignant populations within this microenvironment. We focus on representative bioactive factors regulating this intercellular crosstalk. We describe the possible key factors and signalling cascades responsible for the high complexity of the melanoma microenvironment and its premetastatic niches. Furthermore, we present the concept of melanoma early becoming a systemic disease. This systemic effect is presented as a background for the new horizons in the therapy of cutaneous melanoma.

Melanoma xenotransplant on the chicken chorioallantoic membrane: a complex biological model for the study of cancer cell behaviour

The globally increasing incidence of cancer, including melanoma, requires novel therapeutic strategies. Development of successful novel drugs is based on clear identification of the target mechanisms responsible for the disease progression. The specific cancer microenvironment represents a critically important aspect of cancer biology, which cannot be properly studied in simplistic cell culture conditions. Among other traditional options, the study of melanoma cell growth on the chicken chorioallantoic membrane offers several significant advantages. This model offers increased complexity compared to usual in silico culture models and still remains financially affordable. Using this model, we studied the growth of three established human melanoma cell lines: A2058, BLM, G361. The combination of histology, immunohistochemistry with the application of human-specific antibodies, intravascular injection of contrast material such as filtered Indian ink, Mercox solution and phosphotungstic acid, and X-ray micro-CT and live-cell monitoring was employed. Melanoma cells spread well on the chicken chorioallantoic membrane. However, invasion into the stroma of the chorioallantoic membrane and the limb primordium graft was rare. The melanoma cells also significantly influenced the architecture of the blood vessel network, resulting in the orientation of the vessels to the site of the tumour cell inoculation. The system of melanoma cell culture on the chorioallantoic membrane is suitable for the study of melanoma cell growth, particularly of rearrangement of the host vascular pattern after cancer cell implantation. The system also has promising potential for further development.

Natural anti-aging skincare: role and potential

The deterioration of the skin morphology and physiology is the first and earliest obvious harbinger of the aging process which is progressively manifested with increasing age. Such deterioration affects the vital functions of the skin such as homeodynamic regulation of body temperature, fluid balance, loss of electrolytes and proteins, production of vitamin D, waste removal, immune surveillance, sensory perception, and protection of other organs against deleterious environmental factors. There are, however, harmful chemicals and toxins found in everyday cosmetics that consumers are now aware of. Thus, the natural beauty industry is on the rise with innovative technology and high-performance ingredients as more consumers demand healthier options. Therefore, the aims of this review are to give some critical insights to the effects of both intrinsic and extrinsic factors on excessive or premature skin aging and to elaborate on the relevance of natural beauty and natural anti-aging skincare approaches that will help consumers, scientists and entrepreneurs make the switch. Our recent investigations have shown the potential and relevance of identifying more resources from our rich natural heritage from various plant sources such as leaves, fruits, pomace, seeds, flowers, twigs and so on which can be explored for natural anti-aging skincare product formulations. These trending narratives have started to gain traction among researchers and consumers owing to the sustainability concern and impact of synthetic ingredients on human health and the environment. The natural anti-aging ingredients, which basically follow hormetic pathways, are potentially useful as moisturizing agents; barrier repair agents; antioxidants, vitamins, hydroxy acids, skin lightening agents, anti-inflammatory ingredients, and sunblock ingredients.

The Possibility of Using Genotoxicity, Oxidative Stress and Inflammation Blood Biomarkers to Predict the Occurrence of Late Cutaneous Side Effects after Radiotherapy

Despite the progresses performed in the field of radiotherapy, toxicity to the healthy tissues remains a major limiting factor. The aim of this work was to highlight blood biomarkers whose variations could predict the occurrence of late cutaneous side effects. Two groups of nine patients treated for Merkel Cell Carcinoma (MCC) were established according to the grade of late skin toxicity after adjuvant irradiation for MCC: grade 0, 1 or 2 and grade 3 or 4 of RTOG (Radiation Therapy Oncology Group)/EORTC (European Organization for Research and Treatment of Cancer). To try to discriminate these 2 groups, biomarkers of interest were measured on the different blood compartments after ex vivo irradiation. In lymphocytes, cell cycle, apoptosis and genotoxicity were studied. Oxidative stress was evaluated by the determination of the erythrocyte antioxidant capacity (superoxide dismutase, catalase, glutathione peroxidase, reduced and oxidized glutathione) as well as degradation products (protein carbonylation, lipid peroxidation). Inflammation was assessed in the plasma by the measurement of 14 cytokines. The most radiosensitive patients presented a decrease in apoptosis, micronucleus frequency, antioxidant enzyme activities, glutathione and carbonyls; and an increase in TNF-a (Tumor Necrosis Factor a), IL-8 (Interleukin 8) and TGF-β1 (Transforming Growth Factor β1) levels. These findings have to be confirmed on a higher number of patients and before radiotherapy and could allow to predict the occurrence of late skin side effects after radiotherapy.