Structural and Functional Changes and Possible Molecular Mechanisms in Aged Skin

Promoting collagen synthesis: a viable strategy to combat skin ageing

Skin ageing is a complex physiological process primarily characterised by the deepening of wrinkles and the sagging of the skin. Collagen is essential for maintaining skin elasticity and firmness. As skin ages, it experiences structural and functional changes in collagen, including a decrease in collagen synthesis and an increase in collagen hydrolysis. Thus, promoting collagen synthesis represents a practical strategy for mitigating skin ageing. This review systematically described the functions, classifications and biosynthesis process of collagen, as well as its role in skin ageing. Additionally, the major signalling pathways and targets associated with collagen synthesis were also discussed. More importantly, the review provided a detailed summary of natural products with collagen synthesis-promoting effects and highlighted small molecule compounds with potential anti-ageing activity, especially PPARδ agonists. The relevant content offers potential targets and lead compounds for the development of anti-skin ageing therapies.

Epigenetic Modifications in Vitiligo

Vitiligo is an autoimmune depigmenting skin disorder and can affect the mental health of the patients. Current research suggests that the development of vitiligo involves a combination of genetic susceptibility, immune imbalance, and oxidative stress. However, its pathogenesis has not been fully elucidated. Epigenetic modification has gained increasing attention as an emerging way to regulate gene expression at the transcriptional or post-transcriptional level. Currently known modes of epigenetic modification include the regulation of non-coding RNAs, DNA methylation, and histone modification. Studies suggest they play important roles in tumors, immune disorders, and inflammatory diseases. In recent years, the value of epigenetics in the diagnosis, treatment, and prognosis of vitiligo has been explored. They showed the potential to serve as biomarkers and play a therapeutic role. In this review, we summarize the epigenetic modification mechanisms involved in the pathogenesis of vitiligo, including physiological processes such as immune homeostasis, melanocyte survival, cell adhesion and migration, and metabolism. This will help us fully understand the progress of epigenetic research in vitiligo and lay the foundation for targeted therapeutic-related research.

Milk-derived exosome-loaded SS31 as a novel strategy to mitigate UV-induced photodamage in skin

It is widely recognized that ultraviolet (UV) radiation primarily catalyses photodamage in the skin by generating reactive oxygen species (ROS). In this study, we developed a novel antioxidant complex, Exo-SS31, by loading the antioxidant peptide SS31 (also known as MTP-131, elamipretide) into milk-derived exosomes. Our findings indicate that Exo-SS31 is an effective antioxidant capable of mitigating Human dermal fibroblast (HDF) damage induced by ultraviolet exposure, suppressing ROS production, and achieving greater therapeutic efficacy than SS31 alone. This complex can regulate the levels of superoxide dismutase (SOD) and glutathione (GSH) within the skin, inhibit the expression of proteins in pathways such as pMAPK and AP-1 triggered by UV radiation, and reduce the expression of the matrix metalloproteinases MMP1 and MMP3. Through these mechanisms, Exo-SS31 effectively prevents collagen degradation in the dermis and inhibits ultraviolet-induced photodamage. The use of milk-derived exosomes as carriers for antioxidant peptides represents a promising strategy to increase the bioavailability of peptide-based therapeutics.

Unlocking the Therapeutic Potential of Patchouli Leaves: A Comprehensive Review of Phytochemical and Pharmacological Insights

Plant-based products play an increasingly vital role in the pharmaceutical industry, including Pogostemon cablin (Blanco) Benth. (patchouli), which is notable for its rich history and extensive use in traditional medicine. Patchouli has a longstanding historical use as a remedy for a wide range of health conditions, including colds, fevers, headaches, inflammation, digestive disorders, and insect and snake bites. Comprehensive phytochemical studies have revealed that patchouli leaves contain diverse valuable bioactive compounds, notably patchouli alcohol, β-patchoulene, pogostone, α-bulnesene, and β-caryophyllene. Recent studies have demonstrated that patchouli leaves exhibit various pharmacological properties, including anti-oxidant, anti-inflammatory, antimicrobial, antidepressant, and anticancer effects. Despite robust traditional knowledge, specific therapeutic applications of patchouli leaves require scientific validation and standardization of their bioactive compounds. This review provides a comprehensive overview of the existing literature on the phytochemical composition, pharmacological properties, and underlying mechanisms of action of patchouli essential oil (PEO) and plant extracts obtained from patchouli leaves. It offers detailed insights into potential therapeutic applications, aiming to inform and guide future research across multiple medical disciplines. Ultimately, this review underscores the need for further research to validate and develop the medicinal applications of patchouli leaves, providing a foundation for future healthcare advancements.

The Effects of Terrestrial and Aquatic Activities on Foot Health: A Comparative Analysis of Podiatric Disorders

Background/Objectives: This study explores the prevalence of podiatric disorders in relation to factors such as gender, age, and the type of sports activity. Understanding these elements is crucial for implementing effective prevention strategies. Methods: The sample consisted of 70 participants, aged 12 to 30, with 71.4% youths and 28.6% adults, including 50 Portuguese and 20 Spanish individuals, who practiced either terrestrial or aquatic sports at varying training intensities. Statistical analyses were performed on data collected from athletes using chi-square tests and proportion tests. Variables such as exercise intensity and sport type (terrestrial vs. aquatic) were examined. Results: Skin disorders were more frequent in men (70.2%) compared to women (29.8%). Regarding age, 70% of individuals aged 19 to 30 years presented dermatoses, compared to 36% in the 12 to 18-year-old group. Exercise intensity also had an impact: 53.8% of athletes engaging in moderate activity exhibited keratoses, compared to 30.8% of those practicing intense activity. Additionally, athletes in terrestrial sports showed an average of 5.2 podiatric disorders, significantly higher than the 3.2 average in aquatic sports. Specifically, terrestrial athletes have a higher prevalence of pinch callus (84.6%) and hyperkeratosis on metatarsal heads (85.7%), while aquatic athletes have more onychomycosis (91.7%) and less hyperkeratosis. A higher prevalence of rotated toes (61.4%) and subungual hematoma (90.9%) was also observed in terrestrial athletes. Conclusions: The prevalence of podiatric disorders is significantly related to gender, age, and the type of physical activity. Men and young adults are more prone to dermatoses, while athletes engaging in moderate intensity activity and those athletes in terrestrial sport face a higher risk of podiatric issues. These findings highlight the need for prevention and treatment strategies in relation to the specific characteristics of each group.

Antioxidant effects of Gastrodia elata polysaccharide-based hydrogels loaded with puerarin/gelatin microspheres for D-galactose-induced aging-skin wound healing

The healing of wounds in aging skin is a challenging issue that has not been thoroughly studied. Composite hydrogels made from natural polysaccharides have shown potential as dressings for various types of wounds. In this study, we prepared a polysaccharide-based composite hydrogel to provide a new strategy for treating aging skin wounds. First, chitosan (CS) was modified and Gastrodin (GAS) was grafted onto its main chain structure to obtain GAS/CS. Then GAS/CS was mixed with oxidized Gastrodia elata polysaccharides (GEP) to form a hydrogel using the principle of adsorbent reaction, and Puerarin (PUE), a natural plant ingredient, was embedded by gelatin microspheres and then loaded into the hydrogel. As a result, the composite hydrogel effectively reduced oxidative stress in tissue cells at the wound site and inhibited bacterial growth. It also reduced inflammation, promoted angiogenesis, and enhanced collagen deposition, which facilitated the repair of all aspects of the wound healing process in aging mouse skin. In short, this study explored the anti-aging effects of polysaccharides from Gastrodia elata, which might serve as both a treatment and an auxiliary for aging skin wounds. Additionally, the Gastrodia elata polysaccharide hydrogel was expected to be a promising drug carrier for skin repair.

Nanowire-based squalene oleogel repairs skin photoaging

Long-term exposure to ultraviolet B (UVB) radiation induces the accumulation of free radicals in the skin, resulting in oxidative damage and accelerated aging. As a natural anti-oxidant, squalene has been applied as a cosmetic additive. Nonetheless, the liquid oil state of squalene and its low solubility in water usually limits the practical application of squalene. Recently, phosphotungstate calcium nanowires has been synthesized to gelatinize oily solvents, making it feasible to fabricate stable oleogel formulation containing squalene. Herein, the squalene/phosphotungstate calcium nanowires (Sql/PWC) oleogel has been specifically designed and applied to treat skin photoaging. Such oleogel was comprised of oil-based structures that closely mimic the skin's natural lipids, resulting in enhanced skin penetration, better retention of active ingredients within the skin, and superior stability as compared to traditional hydrogel, especially under UVB exposure. It was found that the application of Sql/PWC oleogel on UVB-irradiated skin successfully decreased epidermal thickness, increased dermal thickness, and promoted the expression of elastin, collagen and skin barrier marker. Meanwhile, RNA-Sequencing results further revealed that the Sql/PWC oleogel alleviated UVB photo-damage through its antioxidant and anti-inflammatory activities in the skin, which were key factors in the aging process. We believe this study will not only bring new perspectives for skin photoaging treatment but also promotes the broader application of oleogel in the cosmetics industry.

Deciphering the role of skin aging in pigmentary disorders

Skin aging is a complex biological process involving intrinsic and extrinsic factors. Skin aging contains alterations at the tissue, cellular, and molecular levels. Currently, there is increasing evidence that skin aging occurs not only in time-dependent chronological aging but also plays a role in skin pigmentary disorders. This review provides an in-depth analysis of the impact of skin aging on different types of pigmentary disorders, including both hyperpigmentation disorders such as melasma and senile lentigo and hypopigmentation disorders such as vitiligo, idiopathic guttate hypomelanosis and graying of hair. In addition, we explore the mechanisms of skin aging on pigmentation regulation and suggest several potential therapeutic approaches for skin aging and aging-related pigmentary disorders.

Curcumin-Loaded Lipid Nanocarriers: A Targeted Approach for Combating Oxidative Stress in Skin Applications

Background/Objectives: Oxidative stress significantly impacts skin health, contributing to conditions like aging, pigmentation, and inflammatory disorders. Curcumin, with its potent antioxidant properties, faces challenges of low solubility, stability, and bioavailability. This study aimed to encapsulate curcumin in three lipid nanocarriers-solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), and nanoemulsions (NEs)-to enhance its stability, bioavailability, and antioxidant efficacy for potential therapeutic applications in oxidative-stress-related skin disorders. Methods: The lipid nanocarriers were characterized for size, polydispersity index, ζ-potential, and encapsulation efficiency. Stability tests under various conditions and antioxidant activity assays (DPPH and FRAP methods) were conducted. Cytotoxicity in human dermal fibroblasts was assessed using MTT assays, while the expression of key antioxidant genes was evaluated in human dermal fibroblasts under oxidative stress. Skin penetration studies were performed to analyze curcumin's distribution across the stratum corneum layers. Results: All nanocarriers demonstrated high encapsulation efficiency and stability over 90 days. NLCs exhibited superior long-term stability and enhanced skin penetration, while NE formulations facilitated rapid antioxidant effects. Antioxidant assays confirmed that curcumin encapsulation preserved and enhanced its bioactivity, particularly in NLCs. Gene expression analysis revealed upregulation of key antioxidant markers (GPX1, GPX4, SOD1, KEAP1, and NRF2) with curcumin-loaded nanocarriers under oxidative and non-oxidative conditions. Cytotoxicity studies confirmed biocompatibility across all formulations. Conclusions: Lipid nanocarriers effectively enhance curcumin's stability, antioxidant activity, and skin penetration, presenting a targeted strategy for managing oxidative stress in skin applications. Their versatility offers opportunities for tailored therapeutic formulations addressing specific skin conditions, from chronic disorders like psoriasis to acute stress responses such as sunburn.

From Polydeoxyribonucleotides (PDRNs) to Polynucleotides (PNs): Bridging the Gap Between Scientific Definitions, Molecular Insights, and Clinical Applications of Multifunctional Biomolecules

Polydeoxyribonucleotides (PDRNs) and polynucleotides (PNs) are similar DNA-derived biopolymers that have garnered significant scientific attention since the 1990s for their potential applications in wound healing and skin rejuvenation. These biopolymers exhibit a broad molecular weight (MW) range, typically spanning from 50 to 1500 kDa. However, recent studies have expanded this range to encompass fragments as small as 1 kDa and as large as 10,000 kDa. Clinically, PDRN/PN formulations, commercially available in various galenic forms (gels, creams, serums, masks, and injectables), have demonstrated promising effects in significantly promoting skin regeneration, reducing inflammation, improving skin texture, preventing scar formation, and mitigating wrinkles. Importantly, despite their widespread use in cosmetology and aesthetic dermatology, the interchangeable use of the terms "PDRN" and "PN" in the scientific literature (to describe polymers of varying lengths) has led to considerable confusion within the medical and scientific communities. To specifically address this PDRN/PN ambiguity, this narrative review proposes a standardized structure-based nomenclature for these DNA-derived polymers, the "Marques Polynucleotide Cutoff", set at 1500 kDa. Thus, we propose that the term "PDRN" should be exclusively reserved for small- and medium-chain polymers (MW < 1500 kDa), while the term "PN" should specifically be used to denote longer-chain polymers (MW ≥ 1500 kDa). In a broader perspective, this classification is based on the distinct physicochemical properties and therapeutic effects of these DNA fragments of various MWs, which are comprehensively discussed in the present review.

Caffeine as an Active Molecule in Cosmetic Products for Hair Loss: Its Mechanisms of Action in the Context of Hair Physiology and Pathology

Caffeine has recently attracted attention as a potential remedy for hair loss. In the present review, we look into the molecule's possible mechanisms of action and pharmacodynamics. At the molecular level, it appears that the physiological effects of caffeine are mainly due to the molecule's interaction with adenosine pathways which leads to an increase in cAMP level and the stimulation of metabolic activity in the hair follicle. Moreover, caffeine also acts as an antioxidant and may prevent degenerative processes. While the intact stratum corneum seems virtually impenetrable to caffeine and a range of physical and chemical methods have been proposed to facilitate its penetration, hair follicles seem to be both a main entry route into the skin and target structures for caffeine at the same time. Caffeine readily forms bonds with water and other molecules which may influence its bioavailability and should be taken into account when engineering future hair products. The results of clinical studies published so far seem promising; however, the majority of the studies of caffeine-based hair loss products offer a very low level of evidence due to considerable flaws in study designs. Nevertheless, the metabolic activity of caffeine and its ability to enter and accumulate in the hair follicles combined with the results of available clinical trials seem to indicate that caffeine could indeed prove as an effective and safe option in the management of hair loss.

Exploring the Role of Herbal Compounds in Skin Aging: A Systematic Review of Topical Approaches

Recently, dermatology has increasingly focused on understanding skin aging and exploring novel therapeutic approaches. Despite progress in cosmetic and pharmaceutical research, a significant gap remains in comprehensively understanding the effects and mechanisms of herbal extracts on skin aging. While many studies have examined the bioactivities of herbal compounds in preclinical models, comprehensive human trials have been scarce over the past decade. This review aims to address this gap by synthesizing human trials from the past decade, focusing on the therapeutic effects of herbal extracts on skin aging. The objective is to unravel the mechanisms contributing to skin aging and assess the therapeutic potential of herbal compounds. Following the PRISMA 2020 guideline, a systematic review was performed across OvidMEDLINE, Cochrane Central Register of Controlled Trials, and Embase via Ovid. A meticulous search strategy identified relevant clinical trials. The review highlights the essential role of herbal compounds in skin aging, particularly their antioxidant activity in suppressing the aging process. Analysis of 51 clinical trials offers valuable insights into their diverse effects on skin aging parameters. Herbal compounds are promising alternatives to synthetic products for treating skin aging. Their demonstrated efficacy in mitigating wrinkles, enhancing elasticity, maintaining hydration, and controlling pigmentation underscores their potential in developing antiaging therapeutics. However, further studies are needed to identify specific compounds responsible for these effects and understand their mechanisms. Future directions include conducting large-scale trials, exploring synergies with other ingredients, and optimizing delivery systems for sustainable, effective antiaging therapies.

Nanoformulated phytochemicals in skin anti-aging research: an updated mini review

Skin aging is characterized by progressive loss of functionality and regenerative potential of the skin, resulting in the appearance of wrinkles, irregular pigmentation, a decrease of elasticity, dryness, and rough texture. Damage to the skin caused by oxidative stress could substantially be slowed down by the use of phytochemicals that function as natural antioxidants. Although phytochemicals have immense potential as anti-aging medicines, their effectiveness as therapeutic agents is restricted by their poor solubility, biodistribution, stability, and hydrophilicity. Given their improved stability, solubility, efficacy, and occlusive properties, nanoformulations have emerged as promising drug delivery platforms for phytochemicals to achieve anti-aging effects. The efficacy of these nanoformulated phytochemicals in suppressing enzymes that accelerate skin aging, such as collagenase, tyrosinase and hyaluronidase, as well as enhancing superoxide dismutase, catalase, and collagen levels to improve skin appearance during aging has been demonstrated.

Quality by Design Approach for the Formulation and Evaluation of Stem Cells Derived Rosmarinic Acid-Loaded Nanofibers as an Anti-Wrinkle Patch: In Vitro and In Vivo Characterizations

Background/Objectives: Skin wrinkles result from a myriad of multifaceted processes involving intrinsic and extrinsic aging. To combat this effect, plant stem cells offer a renewable and eco-friendly source for various industries, including cosmeceuticals. Salvia miltiorrhiza (SM), which contains the bioactive compound Rosmarinic acid (RA) and has been proposed for its anti-wrinkle effect. Methods: In the present study, calli from SM were cultured and Quality by Design (QbD) was implemented to investigate the effect of different types and concentrations of elicitors; jasmonic acid (JA) and salicylic acid (SA). Both raised RA levels yet, jasmonic acid (50 µM) has resulted in the highest yield for RA, at 16 mg/g. A nanofiber patch was prepared and characterized in-vitro by the release percentage, drug content, swelling degree, scanning electron microscope, and surface roughness. Then, the anti-wrinkle effect of the patch was tested in a UV wrinkle-induced mouse model. Results: Interestingly, after treatment, there were visibly fewer wrinkles, and the skin was softer than in the untreated control group. This study suggests that the treatment exerted its effect through the Nrf2/Keap1 pathway, which plays a crucial role in cellular antioxidant protective processes. By activating this pathway through boosting Nrf2 and diminishing Keap1 cellular content, the nanofiber patch enhances the production of antioxidant enzymes, such as superoxide dismutase and glutathione peroxidase, enhancesglutathione, and reduces the skin lipid peroxidation, collectively indicating enhanced skin quality. Conclusions: In conclusion, this study highlights the importance of this formula as an anti-wrinkle treatment, and future clinical studies are recommended to further unveil the potential of this formula.

Breast cancer radiotherapy in Sub-Saharan Africa: a comparative study of acute toxicity between conventional and hypofractionated treatment regimens

Hypofractionated radiotherapy for breast cancer has been increasingly adopted globally due to its comparable efficacy and reduced treatment burden. The study compared the incidence and severity of four main acute radiation-induced toxicities between breast cancer patients treated with conventional versus hypofractionated radiotherapy. Stratified purposive sampling was used to recruit participants into two groups: group #1 received conventional radiotherapy (50 Gy in 25 fractions over 5 weeks), whereas group #2 received hypofractionated radiotherapy (40.05 Gy in 15 fractions over 3 weeks). A closed-ended questionnaire administered by the researcher was used for quantitative data collection. The Common Terminology Criteria for Adverse Events tool (version 5) was used for grading acute toxicities. Data were analyzed using the Statistical Package for Social Sciences (version 23). The study involved 53 patients with a mean age of 47.9 years (± 12.4) ranging from 26 to 75 years. The patients had breast cancer ranging from stage IIA (13.2%) to IIIC (9.4%). A considerable majority (62.3%) were treated with conventional fractionation whereas 37.7% were treated with a hypofractionated regimen. Dermatitis was the most prevalent side effect among patients in both groups #1 (67%) and #2 (70%). There were no statistically significant differences in the incidence of dermatitis, pharyngitis, chest wall/ breast pain and fatigue between the two groups. However, the mean incidence of overall acute toxicity was significantly lower in group #2 (2.15 ± 1.14) compared with group #1 (2.42 ± 1.48), with a p-value of 0.001. Comparatively, the conventional 50 Gy dose regimen was associated with more acute radiation-induced toxicity.

Photoaging protective effect of enzyme extracted pomegranate peel against oxidative damage in UVB-irradiated HaCaT cells

In this study, the ultraviolet B (UVB)-induced skin photoaging inhibitory activity of pomegranate peel extract with increased ellagic acid content through enzymatic hydrolysis was evaluated in HaCaT cells. Among various enzymes, Viscozyme with high tannase and β-glucosidase activities was used, and 1.0 % Viscozyme was added to hydrolyze pomegranate peel for 2 h at 40°C to establish the optimal reaction conditions for high ellagic acid content. Subsequently, when cells were treated with enzyme extracted pomegranate peels (40 μg/mL), the gene expression of matrix metalloproteinases (MMP)-2 and 13, which play key role in skin elasticity and moisture, and the protein expression of MMP13 were downregulated compared to the UVB-control group (UVB-C). In addition, the protein expression levels of tissue inhibitors, metalloproteinase-1 and 2, and collagen type I alpha 1 were upregulated, the gene expression of hyaluronic acid synthase-1, and filaggrin significantly increased, and interleukin-1β increased by photoaging was decreased. Furthermore, compared to the UVB-C, there was a significant increase in the gene expression of superoxide dismutase-1 and glutathione peroxidase, which resulted in a decrease in reactive oxygen species and malondialdehyde levels. These results were confirmed to be due to the inhibition of the mitogen-activated protein kinase pathway and downregulation of the protein expression of phosphorylated extracellular signal-regulated kinase, c-Jun N-terminal kinase, and P38. In conclusion, pomegranate peel, from which ellagic acid was extracted using Viscozyme, showed a reactive oxygen species inhibitory effect in UVB-irradiated HaCaT cells and thus may have a significant potential as a cosmetic ingredient with anti-aging effects.

A Randomized, Single-Center, Double-Blind, Controlled Case Study Evaluating Procedure Pairing of a Neurocosmetic Postprocedure Cream With Radiofrequency Microneedling for Facial Rejuvenation

BACKGROUND

Radiofrequency (RF) microneedling produces patient discomfort which deters patients from completing the recommended treatment series.

OBJECTIVE

The primary objective was to determine the tolerability, safety, and efficacy of a neurocosmetic postprocedure cream post-RF microneedling in reducing patient discomfort and enhancing recovery across the length of the study and, secondarily, to evaluate against a leading comparator. The third objective was to evaluate the efficacy of the neurocosmetic on self-perceived improvement and objective grading.

MATERIALS AND METHODS

An Institutional Review Board (IRB) approved, fourteen-day, randomized, single-center, double-blind, controlled clinical case study was conducted with 11 healthy female subjects, 6 randomized to the neurocosmetic and 5 to the comparator cell. Following a 7-day washout period, subjects received RF microneedling (face and neck) and applied the postprocedure cream twice daily for 7 days. Objective and subjective tolerability, self-assessments, and clinical photography were performed immediately postprocedure, 24 h, three and seven days following the procedure.

RESULTS

The neurocosmetic was tolerable and safe. Erythema and stinging immediately decreased postprocedure, postneurocosmetic application. After 24 h, 83% favorably agreed the neurocosmetic "reduced irritation on the skin post-procedure," and after 7 days, 100% favorably agreed "experience with the product was positive and I would be interested in returning for a second treatment." The neurocosmetic reduced skin tone redness in the face and neck faster and to a greater degree when measured against a comparator.

CONCLUSION

The neurocosmetic postprocedure cream improved patient discomfort and enhanced recovery when used immediately post-RF microneedling and after 7 days.

IRB PROTOCOL NUMBER

Pro00064211.

Age-related changes in the bacterial composition of healthy female facial skin in Beijing area

OBJECTIVE

Exploring the effects of age on microbial community structure and understanding the effects of chronological ageing as well as sun exposure on microbial community diversity.

METHOD

The microbial characteristics of the facial skin of 98 adult women aged 18-70 years were studied using 16S rRNA gene sequencing, and differences based on age and reported sun exposure were assessed.

RESULTS

The cheek skin's bacterial diversity and richness increased with age. The relative abundance of Cutibacterium decreased with age, while the relative abundance of Corynebacterium, Anaerococcus, Paracoccus, Micrococcus, Kocuria, Kytococcus, and Chryseobacterium increased. In addition, an increase in Micrococcus and a decrease in Cutibacterium were observed in volunteers with more than 2 h of daily sun exposure compared to volunteers with <2 h of daily sun exposure. Under low-sunlight conditions, Cutibacterium was more prevalent in the youth group, and Corynebacterium, Anaerococcus, and Kytococcus were more prevalent in the older group.

CONCLUSION

The diversity and composition of the bacterial community on the cheeks are affected by age and extrinsic factors (sun exposure) may also play a role in this.

Biotics as novel therapeutics in targeting signs of skin ageing via the gut-skin axis

Skin ageing is a phenomenon resulting from the aggregative changes to skin structure and function and is clinically manifested by physical features such as wrinkles, hyperpigmentation, elastosis, telangiectasia, and deterioration of skin barrier integrity. One of the main drivers of skin ageing, UV radiation, negatively influences the homeostasis of cells and tissues comprising the skin by triggering production of immune-mediated reactive oxygen species (ROS) and pro-inflammatory cytokines, as well as a various hormones and neuropeptides. Interestingly, an established link between the gut and the skin coined the 'gut-skin axis' has been demonstrated, with dysbiosis and gut barrier dysfunction frequently observed in certain inflammatory skin conditions and more recently, implicated in skin ageing. Therapeutic use of 'biotics' including prebiotics, probiotics, postbiotics, and synbiotics, which modulate the gut microbiota and production of microbially associated metabolites, influence the activity of the gut mucosal and immune systems and are showing promise as key candidates in addressing signs of skin ageing. In this review we aim to focus on the structure and function of the gut-skin axis and showcase the recent in-vitro and clinical evidence demonstrating the beneficial effects of select biotics in targeting signs of skin ageing and discuss the proposed mechanisms mediated via the gut-skin axis underpinning these effects.

Moisturizing Effects of Alcalase Hydrolysate Fractions from Haliotis discus Viscera, a Marine Organism, on Human Dermal Fibroblasts, HaCaT Keratinocytes, and Reconstructed Human Skin Tissues

Haliotis discus, an abalone, is a marine gastropod mollusk that has been cultivated globally owing to its nutritional value and high market demand. However, the visceral parts of H. discus are typically discarded as by-products, highlighting the need to explore their potential value in developing cosmeceuticals and pharmaceuticals. This study investigated the potential moisturizing effects of H. discus visceral tissues. Various hydrolysates from H. discus viscera tissue were evaluated for proximate composition, radical scavenging, and hyaluronidase inhibition activities. Alcalase hydrolysate was isolated using gel filtration chromatography (GFC), and its moisturizing effects were tested on human dermal fibroblasts (HDF), HaCaT keratinocytes, and reconstructed human skin tissue. The Alcalase hydrolysate showed the highest extraction yield, radical scavenging, and hyaluronidase inhibition activities. The Alcalase hydrolysate GFC fraction 1 increased collagen synthesis-related molecules, including procollagen type 1 in HDF and hyaluronic acid-related molecules in HaCaT cells. These moisturizing effects were confirmed in reconstructed human skin tissues by increased levels of aquaporin 3 and filaggrin. Fraction 1 consisted of two main peptides: DNPLLPGPPF and SADNPLLPGPPF. In conclusion, H. discus Alcalase hydrolysate and its fractions have potential moisturizing properties and can be used as cosmeceuticals.

Skin senescence-from basic research to clinical practice

The most recognizable implications of tissue aging manifest themselves on the skin. Skin laxity, roughness, pigmentation disorders, age spots, wrinkles, telangiectasia or hair graying are symptoms of physiological aging. Development of the senescent phenotype depends on the interaction between aging cells and remodeling of the skin's extracellular matrix (ECM) that contains collagen and elastic fiber. Aging changes occur due to the combination of both endogenous (gene mutation, cellular metabolism or hormonal agents) and exogenous factors (ultraviolet light, environmental pollutants, and unsuitable diet). However, overproduction of mitochondrial reactive oxygen species (ROS) is a key factor driving cellular senescence. Aging theories have disclosed a range of diverse molecular mechanisms that are associated with cellular senescence of the body. Theories best supported by evidence include protein glycation, oxidative stress, telomere shortening, cell cycle arrest, and a limited number of cell divisions. Accumulation of the ECM damage is suggested to be a key factor in skin aging. Every cell indicates a functional and morphological change that may be used as a biomarker of senescence. Senescence-associated β-galactosidase (SA-β-gal), cell cycle inhibitors (p16INK4a, p21CIP1, p27, p53), DNA segments with chromatin alterations reinforcing senescence (DNA-SCARS), senescence-associated heterochromatin foci (SAHF), shortening of telomeres or downregulation of lamina B1 constitute just an example of aging biomarkers known so far. Aging may also be assessed non-invasively through measuring the skin fluorescence of advanced glycation end-products (AGEs). This review summarizes the recent knowledge on the pathogenesis and clinical conditions of skin aging as well as biomarkers of skin senescence.

Role of fibroblast autophagy and proliferation in skin anti-aging

Skin, as the outermost protective barrier of the body, becomes damaged with age and exposure to external stimuli. Dermal fibroblasts age and undergo apoptosis, which decreases collagen, collagen fibers, elastic fibers, hyaluronic acid, etc., leading skin to loss of elasticity and appearance of wrinkles. Skin aging is complex, involving several biological reactions，and various treatment methods are used to treat it. This review focuses on the importance of autophagy and cell proliferation in skin anti-aging, summarizes research progress on skin anti-aging by regulating autophagy and promoting the proliferation of dermal fibroblasts, and discusses future directions on skin anti-aging research.

Tailoring biomaterials for skin anti-aging

Skin aging is the phenomenon of degenerative changes in the structure and function of skin tissues over time and is manifested by a gradual loss of skin elasticity and firmness, an increased number of wrinkles, and hyperpigmentation. Skin anti-aging refers to a reduction in the skin aging phenomenon through medical cosmetic technologies. In recent years, new biomaterials have been continuously developed for improving the appearance of the skin through mechanical tissue filling, regulating collagen synthesis and degradation, inhibiting pigmentation, and repairing the skin barrier. This review summarizes the mechanisms associated with skin aging, describes the biomaterials that are commonly used in medical aesthetics and their possible modes of action, and discusses the application strategies of biomaterials in this area. Moreover, the synergistic effects of such biomaterials and other active ingredients, such as stem cells, exosomes, growth factors, and antioxidants, on tissue regeneration and anti-aging are evaluated. Finally, the possible challenges and development prospects of biomaterials in the field of anti-aging are discussed, and novel ideas for future innovations in this area are summarized.

Polyphenol-Rich Cranberry Beverage Positively Affected Skin Health, Skin Lipids, Skin Microbiome, Inflammation, and Oxidative Stress in Women in a Randomized Controlled Trial

This study aimed to determine whether a polyphenol-rich cranberry beverage affects skin properties, lipids, and the microbiome in women using a randomized, double-blinded, placebo-controlled, cross-over design. Twenty-two women with Fitzpatrick skin types 2-3 were randomized to drink a cranberry beverage or placebo for six weeks. After a 21-day washout, they consumed the opposite beverage for six weeks. Six weeks of cranberry beverage significantly reduced UVB-induced erythema, improved net elasticity on the face and forearm, smoothness on the face, and gross elasticity on the forearm compared to the placebo. When stratified by age, these effects of the cranberry beverage were primarily observed in women >40 years old. SOD activities were improved after six weeks of cranberry beverage consumption compared to the placebo, while glutathione peroxide and TNF-α were improved compared to baseline. These effects were found to differ by age group. Skin lipid composition was modulated by both the cranberry beverage and the placebo. Cranberry beverages did not change α- or β-diversity but altered the abundance of several skin microbes at the species and strain level. Consumption of a cranberry beverage for six weeks improved specific skin properties and oxidative stress and modulated skin lipids and microbiome compared to placebo.

Efficacy of an Innovative Poly-Component Formulation in Counteracting Human Dermal Fibroblast Aging by Influencing Oxidative and Inflammatory Pathways

Skin aging is characterized by reactive oxygen species (ROS) accumulation, principal players in triggering events associated with aging. Our recent data on the ability of an innovative poly-component formulation (KARISMA Rh Collagen® FACE: K formulation) to suppress the biomolecular events associated with oxidative stress-induced aging prompted us to deepen the mechanisms underlying the observed effects on aged human dermal fibroblasts (HDFs). Here, we evaluated K's ability to perform a direct free radical-scavenging action and modulate anti-oxidant systems by counteracting the inflammatory process in an H2O2-induced cellular senescence model. Standard methods were used to measure scavenging capacity and enzymatic anti-oxidant system activities. Nuclear factor E2-related factor 2 (Nrf2) and nuclear factor kappa-B (NF-κB) levels were analyzed by Western blot. We assessed pro-inflammatory cytokines, matrix metalloproteinases (MMPs), and advanced glycation end-products (AGEs). Our results show that K counteracted stress-induced aging in a dose-dependent manner by exerting a direct scavenging action and increasing anti-oxidant systems, such as superoxide dismutase (SOD) and catalase (CAT) up to control values. These findings could be associated with increased phospho-Nrf2 (p-Nrf2) expression, generally reduced in aged HDFs following exposure to different concentrations of K formulation. Moreover, K formulation caused a reduction of pro-inflammatory cytokines, interleukin-1β and -6, MMP-1 and -9, and AGE levels, events related to a downregulation of p-NF-κB level. The results indicate that K formulation re-established the normal physiology of HDFs by reducing p-NF-κB expression and restoring Nrf2 activation, thus supporting its efficacious reparative and regenerative action in treating skin aging.

Development of dissolving microneedles loaded with fucoidan for enhanced anti-aging activity: An in vivo study in mice animal model

Skin aging occurs naturally as essential skin components gradually decline, leading to issues such as fine lines, wrinkles, and pigmentation. Fucoidan, a natural bioactive compound, holds potential for addressing these age-related concerns. However, its hydrophilic nature and substantial molecular weight hinder its absorption into the skin. In this study, we utilized polyvinyl pyrrolidone K30 (PVP) and polyvinyl alcohol (PVA) as polymers to fabricate dissolving microneedles loaded with fucoidan (DMN-F). The DMN-F formulations were examined for physical characteristics, stability, permeability, toxicity, and efficacy in animal models. These formulations exhibited consistent polymer blends with a conical structure and uniform cone-shaped design. Microneedle structure and penetration capability gradually decreased with increasing fucoidan concentration, with storage recommended at approximately 33 % relative humidity (RH). Ex vivo studies showed that DMN-F efficiently delivered up to 95.03 ± 2.36 % of the total fucoidan concentration into the skin. In vivo investigations revealed that DMN-F effectively reduced wrinkles, improved skin elasticity, maintained moisture levels, and increased epidermal thickness. Histological images provided additional evidence of DMN-F's positive effects on these aging parameters. The results confirm that the DMN-F formulation effectively delivers fucoidan into the skin, allowing it to treat and mitigate signs of aging.

Regulatory Mechanisms of Natural Active Ingredients and Compounds on Keratinocytes and Fibroblasts in Mitigating Skin Photoaging

Background

The mechanism underlying skin photoaging remains elusive because of the intricate cellular and molecular changes that contribute to this phenomenon, which have yet to be elucidated. In photoaging, the roles of keratinocytes and fibroblasts are vital for maintaining skin structure and elasticity. But these cells can get photo-induced damage during photoaging, causing skin morphological changes. Recently, the function of natural active ingredients in treating and preventing photoaging has drawn more attention, with researches often focusing on keratinocytes and fibroblasts.

Methods

We searched for studies published from 2007 to January 2024 in the Web of Science, PubMed, and ScienceDirect databases through the following keywords: natural plant, natural plant products or phytochemicals, traditional Chinese Medicine or Chinese herbal, plant extracts, solar skin aging, skin photoaging, and skin wrinkling. This review conducted the accordance of Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

Results

In total, 87 researches were included in this review (Figure 1). In keratinocytes, natural compounds may primarily regulate signal pathways such as the NF-κB, MAPK, PI3K/AKT, and Nrf2/ARE pathways, reducing inflammation and cellular damage, thus slowing skin photoaging. Additionally, in fibroblasts, natural active ingredients primarily promote the TGF-β pathway, inhibit MMPs activity, and enhance collagen synthesis while potentially modulating the mTOR pathway, thereby protecting the dermal collagen network and reducing wrinkle formation. Several trials showed that natural compounds that regulate keratinocytes and fibroblasts responses have significant and safe therapeutic effects.

Conclusion

The demand for natural product-based ingredients in sunscreen formulations is rising. Natural compounds show promising anti-photoaging effects by targeting cellular pathways in keratinocytes and fibroblasts, providing potential therapeutic strategies. However, comprehensive clinical studies are needed to verify their efficacy and safety in mitigating photoaging, which should use advanced pharmacological methods to uncover the complex anti-photoaging mechanisms of natural compounds.

Dihydroavenanthramide D Enhances Skin Barrier Function through Upregulation of Epidermal Tight Junction Expression

Skin barrier dysfunction and thin epidermis are hallmarks of sensitive skin and contribute to premature aging. Avenanthramides are the primary bioactive components of colloidal oatmeal, a commonly used treatment to enhance skin barrier function. This study investigated the relationship between skin barrier function and epidermal characteristics and explored the potential of dihydroavenanthramide D (dhAvD), a synthetic avenanthramide, to improve the skin barrier. We observed a significant correlation between impaired skin barrier function and decreased epidermal thickness, suggesting that a weakened barrier contributes to increased sensitivity. Our in vitro results in HaCaT cells demonstrated that dhAvD enhances keratinocyte proliferation, migration, and tight junction protein expression, thereby strengthening the skin barrier. To mimic skin barrier dysfunction, we treated keratinocytes and full-thickness skin equivalents with IL-4 and IL-13, cytokines that are implicated in atopic dermatitis, and confirmed the downregulation of tight junction and differentiation markers. Furthermore, dhAvD treatment restored the barrier function and normalized the expression of key epidermal components, such as tight junction proteins and natural moisturizing factors, in keratinocytes treated with inflammatory cytokines. In the reconstructed human skin model, dhAvD promoted both epidermal and dermal restoration. These findings suggest that dhAvD has the potential to alleviate skin sensitivity and improve skin barrier function.

Resveratrol activates autophagy and protects from UVA-induced photoaging in human skin fibroblasts and the skin of male mice by regulating the AMPK pathway

Skin photoaging is mostly caused by ultraviolet A (UVA), although active medications to effectively counteract UVA-induced photoaging have not yet been created. Resveratrol, a naturally occurring polyphenol found in the skin of grapes, has been shown to have various biological functions such as anti-inflammatory and antioxidant characteristics. However, the role of resveratrol in UVA-induced photoaging has not been clarified. We investigated the mechanism of action of resveratrol by UVA irradiation of human skin fibroblasts (HSF) and innovatively modified a mouse model of photoaging. The results demonstrated that resveratrol promoted AMP-activated protein kinase (AMPK) phosphorylation to activate autophagy, reduce reactive oxygen species (ROS) production, inhibit apoptosis, and restore normal cell cycle to alleviate UVA-induced photoaging. In addition, subcutaneous injection of resveratrol not only improved the symptoms of roughness, erythema, and increased wrinkles in the skin of UVA photodamaged mice, but also alleviated epidermal hyperkeratosis and hyperpigmentation, reduced inflammatory responses, and inhibited collagen fiber degradation. In conclusion, our studies proved that resveratrol can treat UVA-induced photoaging and elucidated the possible molecular mechanisms involved, providing a new therapeutic strategy for future anti-aging.

Matrikines in the skin: Origin, effects, and therapeutic potential

The extracellular matrix (ECM) represents a complex multi-component environment that has a decisive influence on the biomechanical properties of tissues and organs. Depending on the tissue, ECM components are subject to a homeostasis of synthesis and degradation, a subtle interplay that is influenced by external factors and the intrinsic aging process and is often disturbed in pathologies. Upon proteolytic cleavage of ECM proteins, small bioactive peptides termed matrikines can be formed. These bioactive peptides play a crucial role in cell signaling and contribute to the dynamic regulation of both physiological and pathological processes such as tissue remodeling and repair as well as inflammatory responses. In the skin, matrikines exert an influence for instance on cell adhesion, migration, and proliferation as well as vasodilation, angiogenesis and protein expression. Due to their manifold functions, matrikines represent promising leads for developing new therapeutic options for the treatment of skin diseases. This review article gives a comprehensive overview on matrikines in the skin, including their origin in the dermal ECM, their biological effects and therapeutic potential for the treatment of skin pathologies such as melanoma, chronic wounds and inflammatory skin diseases or for their use in anti-aging cosmeceuticals.

Characterization and Comparative Investigation of Hydroxyapatite/Carboxymethyl Cellulose (CaHA/CMC) Matrix for Soft Tissue Augmentation in a Rat Model

This study endeavors to develop an injectable subdermal implant material tailored for soft tissue repair and enhancement. The material consists of a ceramic phase of calcium hydroxyapatite (CaHA), which is biocompatible, 20-60 μm in size, known for its biocompatibility and minimal likelihood of causing foreign body reactions, antigenicity, and minimal inflammatory response, dispersed in a carrier phase composed of carboxymethyl cellulose (CMC), glycerol, and water for injection. The gel formulation underwent comprehensive characterization via various analytical techniques. X-ray diffraction (XRD) was employed to identify crystalline phases and investigate the structural properties of ceramic particles, while thermogravimetric analysis (TGA) was conducted to evaluate the thermal stability and decomposition behavior of the final formulation. Scanning electron microscopy (SEM) was utilized to examine the surface morphology and particle size distribution, confirming the homogeneous dispersion of spherical CaHA particles within the matrix. SEM analysis revealed particle sizes ranging from approximately 20-60 μm. Elemental analysis confirmed a stoichiometric Ca/P ratio of 1.65 in the hydroxyapatite (HA) structure. Heavy metal content exhibited suitability for surgical implant use without posing toxicity risks. Rheological analysis revealed a storage modulus of 58.6 and 68.9 kPa and a loss modulus of 21.7 and 24.8 kPa at the frequencies of 2 and 5 Hz, respectively. 150 μL of sterilized CaHA/CMC was injected subcutaneously into rats and compared with a similar product, Crystalys, to assess its effects on soft tissues. Skin tissue samples of rats were collected at specific intervals throughout the study (30, 45, 60, 90 and 120 days), and examined histologically. Results demonstrated that CaHA/CMC gel led to a significant increase in dermal thickness, elastic fibers, and collagen density. Based on the findings, the formulated CaHA/CMC gel was found to be biocompatible, biodegradable, nonimmunogenic, nontoxic, safe, and effective, and represents a promising option for soft tissue repair and augmentation.

Antiaging, Brightening, and Antioxidant Efficacy of Fermented Bilberry Extract (Vaccinium myrtillus): A Randomized, Double-Blind, Placebo-Controlled Trial

Strategies for successful aging, including the use of food supplements, are part of the approach to support skin youthfulness. To demonstrate the efficacy of fermented bilberry extract (FBE) against skin aging and uneven complexion, a clinical trial was carried out on 66 subjects with visible "crow's feet" wrinkles, mild-to-moderate skin slackness, and uneven skin tone. The wrinkle depth, skin smoothness (Ra) and roughness (Rz), skin firmness (R0) and elasticity (R2), skin coloration (ITA°), and skin antioxidant capacity were measured before and after 28 (D28), 56 (D56), and 84 (D84) days of product use (either FBE or a placebo). These parameters were also integrated with a clinical evaluation, carried out by a dermatologist, and a self-assessment questionnaire to align the measured efficacy with the visual or perceived efficacy. At D84, the wrinkle depth had decreased by 10.6%, Ra had improved by 7.9%, Rz had decreased by 7.3%, R0 had improved by 13.3%, R2 had improved by 12.4%, and skin antioxidant capacity had increased by 20.8%. ITA° increased by 20.8% and was accompanied by a decrease in the skin's redness component by 16.8% and an increase in the lightness component by 2.2%. The variation of all the above-mentioned parameters was statistically significant between the FBE and PL groups. Our findings demonstrate the efficacy of FBE in improving skin aging and complexion evenness.

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.

Antioxidant, Anti-Inflammation, and Melanogenesis Inhibition of Sang 5 CMU Rice (Oryza sativa) Byproduct for Cosmetic Applications

Prolonged exposure to environmental oxidative stress can result in visible signs of skin aging such as wrinkles, hyperpigmentation, and thinning of the skin. Oryza sativa variety Sang 5 CMU, an inbred rice cultivar from northern Thailand, contains phenolic and flavonoid compounds in its bran and husk portions that are known for their natural antioxidant properties. In this study, we evaluated the cosmetic properties of crude extracts from rice bran and husk of Sang 5 CMU, focusing on antioxidant, anti-inflammatory, anti-melanogenesis, and collagen-regulating properties. Our findings suggest that both extracts possess antioxidant potential against DPPH, ABTS radicals, and metal ions. Additionally, they could downregulate TBARS levels from 125% to 100% of the control, approximately, while increasing the expression of genes related to the NRF2-mediated antioxidant pathway, such as NRF2 and HO-1, in H2O2-induced human fibroblast cells. Notably, rice bran and husk extracts could increase mRNA levels of HO-1 more greatly than the standard L-ascorbic acid, by about 1.29 and 1.07 times, respectively. Furthermore, the crude extracts exhibited anti-inflammatory activity by suppressing nitric oxide production in both mouse macrophage and human fibroblast cells. Specifically, the bran and husk extracts inhibited the gene expression of the inflammatory cytokine IL-6 in LPS-induced inflammation in fibroblasts. Moreover, both extracts demonstrated potential for inhibiting melanin production and intracellular tyrosinase activity in human melanoma cells by decreasing the expression of the transcription factor MITF and the pigmentary genes TYR, TRP-1, and DCT. They also exhibit collagen-stimulating effects by reducing MMP-2 expression in H2O2-induced fibroblasts from 135% to 80% of the control, approximately, and increasing the gene associated with type I collagen production, COL1A1. Overall, the rice bran and husk extracts of Sang 5 CMU showed promise as effective natural ingredients for cosmetic applications.

Exosomes derived stem cells as a modern therapeutic approach for skin rejuvenation and hair regrowth

Background

The skin covers the surface of the body and acts as the first defense barrier against environmental damage. Exposure of the skin to environmental physical and chemical factors such as mechanical injuries, UV rays, air pollution, chemicals, etc. Leads to numerous damages to skin cells such as fibroblasts, keratinocytes, melanocytes, etc. The harmful effects of environmental factors on skin cells could lead to various skin diseases, chronic wounds, wrinkles, and skin aging. Hair is an essential part of the body, serving multiple functions such as regulating body temperature and protecting against external factors like dust (through eyelashes and eyebrows). It also reflects an individual's personality. Therefore, the need for new treatment methods for skin diseases and lesions and at the same time preserving the youth, freshness, and beauty of the skin has been highly noticed by experts. Exosomes are nanovesicles derived from cells that contain various biological compounds such as lipids, proteins, nucleic acids, and carbohydrates. They are secreted by a variety of mammalian cells and even different plants. Exosomes are of great interest as a new therapeutic approach due to their stability, ability to be transported throughout the body, paracrine and endocrine effects, as well as the ability to carry various compounds and drugs to target cells.

Aim

In this review, we have discussed the characteristics of exosomes, their cellular sources, and their therapeutic effects on wrinkles, skin aging, and rejuvenation and hair regrowth.

Potential of Bioactive Protein and Protein Hydrolysate from Apis mellifera Larvae as Cosmeceutical Active Ingredients for Anti-Skin Aging

This study aimed to extract bioactive proteins and protein hydrolysates from Apis mellifera larvae and assess their potential application in cosmetics as well as their irritation properties. The larvae were defatted and extracted using various mediums, including DI water, along with 0.5 M aqueous solutions of sodium hydroxide, ascorbic acid, citric acid, and hydrochloric acid. Subsequently, the crude proteins were hydrolyzed using the Alcalase® enzyme. All extracts underwent testing for antioxidant activities via the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and Griess assays. Anti-aging properties were evaluated in terms of anti-collagenase and anti-hyaluronidase effects. Irritation potential was assessed using the hen's egg chorioallantoic membrane (HET-CAM) test. The results revealed that the sodium hydroxide extraction showed promising outcomes in terms of yield, protein content, and effectiveness in inhibiting hyaluronidase, with the highest inhibition at 78.1 ± 1.5%, comparable to that of oleanolic acid. Conversely, crude protein extracted with ascorbic acid and its hydrolysate showed notable antioxidant and collagenase-inhibitory activities. Remarkably, their anti-collagenase effects were comparable to those of ascorbic acid and lysine. Additionally, it demonstrated safety upon testing with the CAM. In conclusion, the findings provided valuable insights into the utilization of A. mellifera larval proteins as active ingredients with a wide range of cosmeceutical applications, particularly due to their antioxidant, anti-aging, and low irritation properties, which hold significant promise for anti-skin wrinkles.

Role of umbilical cord mesenchymal stromal cells in skin rejuvenation

Aging is the main cause of many degenerative diseases. The skin is the largest and the most intuitive organ that reflects the aging of the body. Under the interaction of endogenous and exogenous factors, there are cumulative changes in the structure, function, and appearance of the skin, which are characterized by decreased synthesis of collagen and elastin, increased wrinkles, relaxation, pigmentation, and other aging characteristics. skin aging is inevitable, but it can be delayed. The successful isolation of mesenchymal stromal cells (MSC) in 1991 has greatly promoted the progress of cell therapy in human diseases. The International Society for Cellular Therapy (ISCT) points out that the MSC is a kind of pluripotent progenitor cells that have self-renewal ability (limited) in vitro and the potential for mesenchymal cell differentiation. This review mainly introduces the role of perinatal umbilical cord-derived MSC(UC-MSC) in the field of skin rejuvenation. An in-depth and systematic understanding of the mechanism of UC-MSCs against skin aging is of great significance for the early realization of the clinical transformation of UC-MSCs. This paper summarized the characteristics of skin aging and summarized the mechanism of UC-MSCs in skin rejuvenation reported in recent years. In order to provide a reference for further research of UC-MSCs to delay skin aging.

Intra-Individual Paired Mass Spectrometry Dataset for Decoding Solar-Induced Proteomic Changes in Facial Skin

Photoaging is the premature aging of the skin caused by prolonged exposure to solar radiation. The visual alterations manifest as wrinkles, reduced skin elasticity, uneven skin tone, as well as other signs that surpass the expected outcomes of natural aging. Beyond these surface changes, there is a complex interplay of molecular alterations, encompassing shifts in cellular function, DNA damage, and protein composition disruptions. This data descriptor introduces a unique dataset derived from ten individuals, each with a minimum of 18 years of professional experience as a driver, who are asymmetrically and chronically exposed to solar radiation due to their driving orientation. Skin samples were independently collected from each side of the face using a microdermabrasion-like procedure and analyzed on an Exploris 240 mass spectrometer. Our adapted proteomic statistical framework leverages the sample pairing to provide robust insights. This dataset delves into the molecular differences in exposed skin and serves as a foundational resource for interdisciplinary research in photodermatology, targeted skincare treatments, and computational modelling of skin health.

Silymarin inhibits dermal gelatinolytic activity and reduces cutaneous inflammation

Milk thistle (Silybum marianum) is well-known for its antioxidant activity due to the presence of silymarin. Albeit some studies show a potential for skin inflammation, its activity against dermal MMP-9 and MMP-2 remains to be studied. Silymarin isolated from an S. marianum herbal extract was tested for gelatinase inhibition in the presence of isolated MMP-9 and in dermal adenocarcinome HaCaT cells. Silymarin was then further tested in vivo, using a cutaneous inflammation mice model mediated by reactive oxygen species. Silymarin was able to significantly inhibit gelatinolytic activity in vitro without impairing cell growth and viability. Furthermore, inhibition was more pronounced in cells than with the isolated gelatinase, suggesting an additional effect upon metabolic pathways. In vivo, silymarin was able to reduce ear edema up to 74% and attenuated histological lesions. Results highlight silymarin potential for application in skin inflammatory disorders via gelatinase inhibition.

Research Progress in Skin Aging and Immunity

Skin aging is a complex process involving structural and functional changes and is characterized by a decrease in collagen content, reduced skin thickness, dryness, and the formation of wrinkles. This process is underpinned by multiple mechanisms including the free radical theory, inflammation theory, photoaging theory, and metabolic theory. The skin immune system, an indispensable part of the body's defense mechanism, comprises macrophages, lymphocytes, dendritic cells, and mast cells. These cells play a pivotal role in maintaining skin homeostasis and responding to injury or infection. As age advances, along with various internal and external environmental stimuli, skin immune cells may undergo senescence or accelerated aging, characterized by reduced cell division capability, increased mortality, changes in gene expression patterns and signaling pathways, and altered immune cell functions. These changes collectively impact the overall function of the immune system. This review summarizes the relationship between skin aging and immunity and explores the characteristics of skin aging, the composition and function of the skin immune system, the aging of immune cells, and the effects of these cells on immune function and skin aging. Immune dysfunction plays a significant role in skin aging, suggesting that immunoregulation may become one of the important strategies for the prevention and treatment of skin aging.

Inflammatory Skin Diseases: Focus on the Role of Suppressors of Cytokine Signaling (SOCS) Proteins

Inflammatory skin diseases include a series of disorders characterized by a strong activation of the innate and adaptive immune system in which proinflammatory cytokines play a fundamental role in supporting inflammation. Skin inflammation is a complex process influenced by various factors, including genetic and environmental factors, characterized by the dysfunction of both immune and non-immune cells. Psoriasis (PS) and atopic dermatitis (AD) are the most common chronic inflammatory conditions of the skin whose pathogeneses are very complex and multifactorial. Both diseases are characterized by an immunological dysfunction involving a predominance of Th1 and Th17 cells in PS and of Th2 cells in AD. Suppressor of cytokine signaling (SOCS) proteins are intracellular proteins that control inflammatory responses by regulating various signaling pathways activated by proinflammatory cytokines. SOCS signaling is involved in the regulation and progression of inflammatory responses in skin-resident and non-resident immune cells, and recent data suggest that these negative modulators are dysregulated in inflammatory skin diseases such as PS and AD. This review focuses on the current understanding about the role of SOCS proteins in modulating the activity of inflammatory mediators implicated in the pathogenesis of inflammatory skin diseases such as PS and AD.

Exosomal microRNA-Based therapies for skin diseases

Based on engineered cell/exosome technology and various skin-related animal models, exosomal microRNA (miRNA)-based therapies derived from natural exosomes have shown good therapeutic effects on nine skin diseases, including full-thickness skin defects, diabetic ulcers, skin burns, hypertrophic scars, psoriasis, systemic sclerosis, atopic dermatitis, skin aging, and hair loss. Comparative experimental research showed that the therapeutic effect of miRNA-overexpressing exosomes was better than that of their natural exosomes. Using a dual-luciferase reporter assay, the targets of all therapeutic miRNAs in skin cells have been screened and confirmed. For these nine types of skin diseases, a total of 11 animal models and 21 exosomal miRNA-based therapies have been developed. This review provides a detailed description of the animal models, miRNA therapies, disease evaluation indicators, and treatment results of exosomal miRNA therapies, with the aim of providing a reference and guidance for future clinical trials. There is currently no literature on the merits or drawbacks of miRNA therapies compared with standard treatments.

NAMPT‑NAD+ is involved in the senescence‑delaying effects of saffron in aging mice

As the proportion of the elderly population grows rapidly, the senescence-delaying effects of Traditional Chinese Medicine is being investigated. The aim of the present study was to investigate the senescence-delaying effects of saffron in naturally aging mice. The active ingredients in an aqueous saffron extract were determined using high-performance liquid chromatography (HPLC). Mice were divided into saffron (8- and 16-months-old) and control groups (3-, 8-, and 16-months-old), and saffron extract was administered to the former groups for 8 weeks. The open field test and Barnes maze test were used to evaluate the locomotor activity, learning and memory function of the mice. The levels of inflammatory factors in the brain were determined by ELISA. In addition, the activities of acetylcholinesterase (AChE) and superoxide dismutase, and the contents of malondialdehyde and nicotinamide adenine dinucleotide (NAD+) were detected by enzyme immunoassay, and the content of NAMPT was detected by ELISA, western blotting and reverse transcription-quantitative PCR. The cellular distribution of NAMPT and synaptic density were evaluated by immunofluorescence, and the pathological morphologies of the liver, skin, kidneys were observed by hematoxylin and eosin staining. HPLC revealed that the crocin and picrocrocin contents of the saffron extract were 19.56±0.14 and 12.00±0.13%, respectively. Saffron exhibited the potential to improve the learning and memory function in aging mice as it increased synaptic density and decreased AChE activity. Also, saffron ameliorated the pathological changes associated with organ aging, manifested by increasing the number of hepatocytes and the thickness of the skin, and preventing the aging-induced ballooning and bleeding in the kidneys. Furthermore, saffron increased the contents of NAMPT and NAD+ in the brain and decreased the content of NAMPT in the serum. In addition, it changed the cellular distribution of NAMPT in aging mice, manifested as reduced NAMPT expression in microglia and astrocytes, and increased NAMPT expression in neurons. Saffron also decreased the contents of proinflammatory cytokines and oxidative stress factors in aging mice. Altogether, these findings indicate that saffron exerts senescence-delaying effects in naturally aging mice, which may be associated with the NAMPT-NAD+ pathway.

Oral intake of collagen hydrolysate from mackerel scad (Decapterus macarellus) attenuates skin photoaging by suppressing the UVB-induced expression of MMP-1 and IL-6

OBJECTIVES

Excessive skin exposure to UVB radiation can induce photoaging caused by an imbalance in oxidative stress and inflammatory responses, damaging the skin's structure and surface layer. A previous study revealed that collagen hydrolisate extracted from the skin of mackarel scads (Decapterus macarellus) had antiaging properties that were tested in vitro, which serves as a foundation for a subsequent study of its use in vivo. This study aimed at investigating the repair effect of the mackerel scad's skin collagen hydrolysate (MSS-CH) in photoaging conditions in a mouse model.

METHODS

MSS-CH was given orally in mice model of skin photoaging under chronic exposure to UVB irradiation for 12 weeks. Morphological and histological changes on the skin were evaluated using SEM and HE staining, along with the measurement of the expression of matrix metalloproteinases (MMP-1) and cytokine pro-inflammatory interleukin 6 (IL-6) using ELISA.

RESULTS

MSS-CH inhibits the occurrence of epidermal thickening and damage to the dermal layer of the skin. As a result, it restores the epidermis' barrier function and reduces surface damage caused by photoaging. The skin of the MSS-CH treated group exhibited improved physical appearance with reduced fine lines, wrinkles, and enhanced smoothness. Additionally, administering MSS-CH to the mice groups reduced the expression of MMP-1 and IL-6 in UVB-exposed skin.

CONCLUSIONS

Altogether, this in vivo study demonstrates the photoaging-protective properties of CH-MSS, aligning with previous in vitro data. Thus, MSS-CH emerges as a strong candidate for use as an ingredient in nutraceuticals and biocosmetics.

Role of autophagy in skin photoaging: A narrative review

As the largest organ of the human body, the skin serves as the primary barrier against external damage. The continuous increase in human activities and environmental pollution has resulted in the ongoing depletion of the ozone layer. Excessive exposure to ultraviolet (UV) radiation enhances the impact of external factors on the skin, leading to photoaging. Photoaging causes physical and psychological damage to the human body. The prevention and management of photoaging have attracted increased attention in recent years. Despite significant progress in understanding and mitigating UV-induced photoaging, the precise mechanisms through which autophagy contributes to the prevention of photoaging remain unclear. Given the important role of autophagy in repairing UV-induced DNA damage and scavenging oxidized lipids, autophagy is considered a novel strategy for preventing the occurrence of photoaging and other UV light-induced skin diseases. This review aims to elucidate the biochemical and clinical features of photoaging, the relationship of skin photoaging and chronological aging, the mechanisms underlying skin photoaging and autophagy, and the role of autophagy in skin photoaging.

Clinically Actionable Topical Strategies for Addressing the Hallmarks of Skin Aging: A Primer for Aesthetic Medicine Practitioners

In this narrative review, we sought to provide a comprehensive overview of the mechanisms underlying cutaneous senescence, framed by the twelve traditional hallmarks of aging. These include genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, impaired macroautophagy, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, altered intercellular communication, chronic inflammation, and dysbiosis. We also examined how topical interventions targeting these hallmarks can be integrated with conventional aesthetic medicine techniques to enhance skin rejuvenation. The potential of combining targeted topical therapies against the aging hallmarks with minimally invasive procedures represents a significant advancement in aesthetic medicine, offering personalized and effective strategies to combat skin aging. The reviewed evidence paves the way for future advancements and underscores the transformative potential of integrating scientifically validated interventions targeted against aging hallmarks into traditional aesthetic practices.

Clinical evidence of the efficacy and safety of a new multi-peptide anti-aging topical eye serum

BACKGROUND

Skin aging is a complex multifactorial progressive process. With age, intrinsic and extrinsic factors cause the loss of skin elasticity, with the formation of wrinkles, resulting in skin sagging through various pathways. A combination of multiple bioactive peptides could be used as a treatment for skin wrinkles and sagging.

OBJECTIVES

This study aimed to evaluate the cosmetic efficacy of a multi-peptide eye serum as a daily skin-care product for improving the periocular skin of women within the ages of 20-45 years.

METHODS

The stratum corneum skin hydration and skin elasticity were assessed using a Corneometer CM825 and Skin Elastometer MPA580, respectively. The PRIMOS CR technique based on digital strip projection technology was used for skin image and wrinkle analysis around the "crow's feet" area. Self-assessment questionnaires were filled on Day 14 and 28 of product use.

RESULTS

This study included 32 subjects with an average age of 28.5 years. On Day 28, there was a significant decrease in the number, depth, and volume of wrinkles. Skin hydration, elasticity, and firmness increased continuously during the study period, consistent with typical anti-aging claims. A majority of the participants (75.00%) expressed overall satisfaction with their skin appearance after using the product. Most participants noted a visible skin improvement, with an increase in skin elasticity and smoothness, and confirmed the extensibility, applicability, and temperance of the product. No adverse reactions related to product use were observed.

CONCLUSIONS

The multi-peptide eye serum uses a multi-targeted mechanism against skin aging to improve the skin appearance, making it an ideal choice for daily skincare.

Melatonin Exerts Prominent, Differential Epidermal and Dermal Anti-Aging Properties in Aged Human Eyelid Skin Ex Vivo

Human skin aging is associated with functional deterioration on multiple levels of physiology, necessitating the development of effective skin senotherapeutics. The well-tolerated neurohormone melatonin unfolds anti-aging properties in vitro and in vivo, but it remains unclear whether these effects translate to aged human skin ex vivo. We tested this in organ-cultured, full-thickness human eyelid skin (5-6 donors; 49-77 years) by adding melatonin to the culture medium, followed by the assessment of core aging biomarkers via quantitative immunohistochemistry. Over 6 days, 200 µM melatonin significantly downregulated the intraepidermal activity of the aging-promoting mTORC1 pathway (as visualized by reduced S6 phosphorylation) and MMP-1 protein expression in the epidermis compared to vehicle-treated control skin. Conversely, the transmembrane collagen 17A1, a key stem cell niche matrix molecule that declines with aging, and mitochondrial markers (e.g., TFAM, MTCO-1, and VDAC/porin) were significantly upregulated. Interestingly, 100 µM melatonin also significantly increased the epidermal expression of VEGF-A protein, which is required and sufficient for inducing human skin rejuvenation. In aged human dermis, melatonin significantly increased fibrillin-1 protein expression and improved fibrillin structural organization, indicating an improved collagen and elastic fiber network. In contrast, other key aging biomarkers (SIRT-1, lamin-B1, p16INK4, collagen I) remained unchanged. This ex vivo study provides proof of principle that melatonin indeed exerts long-suspected but never conclusively demonstrated and surprisingly differential anti-aging effects in aged human epidermis and dermis.

Cellular Senescence in Human Skin Aging: Leveraging Senotherapeutics

BACKGROUND

As the largest organ in the human body, the skin is continuously exposed to intrinsic and extrinsic stimuli that impact its functionality and morphology with aging. Skin aging entails dysregulation of skin cells and loss, fragmentation, or fragility of extracellular matrix fibers that are manifested macroscopically by wrinkling, laxity, and pigmentary abnormalities. Age-related skin changes are the focus of many surgical and nonsurgical treatments aimed at improving overall skin appearance and health.

SUMMARY

As a hallmark of aging, cellular senescence, an essentially irreversible cell cycle arrest with apoptosis resistance and a secretory phenotype, manifests across skin layers by affecting epidermal and dermal cells. Knowledge of skin-specific senescent cells, such as melanocytes (epidermal aging) and fibroblasts (dermal aging), will promote our understanding of age-related skin changes and how to optimize patient outcomes in esthetic procedures.

KEY MESSAGES

This review provides an overview of skin aging in the context of cellular senescence and discusses senolytic intervention strategies to selectively target skin senescent cells that contribute to premature skin aging.

Approaches in line with human physiology to prevent skin aging

Skin aging is a complex process that is influenced by intrinsic and extrinsic factors that impact the skin's protective functions and overall health. As the body's outermost layer, the skin plays a critical role in defending it against external threats, regulating body temperature, providing tactile sensation, and synthesizing vitamin D for bone health, immune function, and body homeostasis. However, as individuals age, the skin undergoes structural and functional changes, leading to impairments in these essential functions. In contemporary society, there is an increasing recognition of skin health as a significant indicator of overall wellbeing, resulting in a growing demand for anti-aging products and treatments. However, these products often have limitations in terms of safety, effective skin penetration, and potential systemic complications. To address these concerns, researchers are now focusing on approaches that are safer and better aligned with physiology of the skin. These approaches include adopting a proper diet and maintaining healthy lifestyle habits, the development of topical treatments that synchronize with the skin's circadian rhythm, utilizing endogenous antioxidant molecules, such as melatonin and natural products like polyphenols. Moreover, exploring alternative compounds for sun protection, such as natural ultraviolet (UV)-absorbing compounds, can offer safer options for shielding the skin from harmful radiation. Researchers are currently exploring the potential of adipose-derived stem cells, cell-free blood cell secretome (BCS) and other endogenous compounds for maintaining skin health. These approaches are more secure and more effective alternatives which are in line with human physiology to tackle skin aging. By emphasizing these innovative strategies, it is possible to develop effective treatments that not only slow down the skin aging process but also align better with the natural physiology of the skin. This review will focus on recent research in this field, highlighting the potential of these treatments as being safer and more in line with the skin's physiology in order to combat the signs of aging.