Saikosaponin A Recovers Impaired Filaggrin Levels in Inflamed Skin by Downregulating the Expression of FRA1 and c-Jun.

Filaggrin (FLG) is an essential structural protein expressed in differentiated keratinocytes. Insufficient FLG expression contributes to the pathogenesis of chronic inflammatory skin diseases. Saikosaponin A (SSA), a bioactive oleanane-type triterpenoid, exerts anti-inflammatory activity. However, the effects of topically applied SSA on FLG expression in inflamed skin remain unclear. This study aimed to evaluate the biological activity of SSA in restoring reduced FLG expression. The effect of SSA on FLG expression in HaCaT cells was assessed through various biological methods, including reverse transcription PCR, quantitative real-time PCR, immunoblotting, and immunofluorescence staining. TNFα and IFNγ decreased FLG mRNA, cytoplasmic FLG protein levels, and FLG gene promoter-reporter activity compared to the control groups. However, the presence of SSA restored these effects. A series of FLG promoter-reporter constructs were generated to investigate the underlying mechanism of the effect of SSA on FLG expression. Mutation of the AP1-binding site (mtAP1) in the -343/+25 FLG promoter-reporter abrogated the decrease in reporter activities caused by TNFα + IFNγ, suggesting the importance of the AP1-binding site in reducing FLG expression. The SSA treatment restored FLG expression by inhibiting the expression and nuclear localization of FRA1 and c-Jun, components of AP1, triggered by TNFα + IFNγ stimulation. The ERK1/2 mitogen-activated protein kinase signaling pathway upregulates FRA1 and c-Jun expression, thereby reducing FLG levels. The SSA treatment inhibited ERK1/2 activation caused by TNFα + IFNγ stimulation and reduced the levels of FRA1 and c-Jun proteins in the nucleus, leading to a decrease in the binding of FRA1, c-Jun, p-STAT1, and HDAC1 to the AP1-binding site in the FLG promoter. The effect of SSA was evaluated in an animal study using a BALB/c mouse model, which induces human atopic-dermatitis-like skin lesions via the topical application of dinitrochlorobenzene. Topically applied SSA significantly reduced skin thickening, immune cell infiltration, and the expression of FRA1, c-Jun, and p-ERK1/2 compared to the vehicle-treated group. These results suggest that SSA can effectively recover impaired FLG levels in inflamed skin by preventing the formation of the repressor complex consisting of FRA1, c-Jun, HDAC1, and STAT1.

The Skin Histopathology of Pro- and Parabiotics in a Mouse Model of Atopic Dermatitis.

As it has been revealed that the activation of human immune cells through the activity of intestinal microorganisms such as pro- and prebiotics plays a vital role, controlling the proliferation of beneficial bacteria and suppressing harmful bacteria in the intestine has become essential. The importance of probiotics, especially for skin health and the immune system, has led to the emergence of products in various forms, including probiotics, prebiotics, and parabiotics. In particular, atopic dermatitis (AD) produces hypersensitive immunosuppressive substances by promoting the differentiation and activity of immune regulatory T cells. As a result, it has been in the Th1 and Th2 immune balance through a mechanism that suppresses skin inflammation or allergic immune responses caused by bacteria. Furthermore, an immune mechanism has recently emerged that simultaneously controls the expression of IL-17 produced by Th17. Therefore, the anti-atopic effect was investigated by administering doses of anti-atopic candidate substances (Lactobacilus sakei CVL-001, Lactobacilus casei MCL, and Lactobacilus sakei CVL-001 Lactobacilus casei MCL mixed at a ratio of 4:3) in an atopy model using 2,4-dinitrochlorobenzene and observing symptom changes for 2 weeks to confirm the effect of pro-, para-, and mixed biotics on AD. First, the body weight and feed intake of the experimental animals were investigated, and total IgG and IgM were confirmed through blood biochemical tests. Afterward, histopathological staining was performed using H&E staining, Toluidine blue staining, Filaggrin staining, and CD8 antibody staining. In the treatment group, the hyperproliferation of the epidermal layer, the inflammatory cell infiltration of the dermal layer, the expression of CD8, the expression of filaggrin, and the secretion of mast cells were confirmed to be significantly reduced. Lastly, small intestine villi were observed through a scanning microscope, and scoring evaluation was performed through skin damage. Through these results, it was confirmed that AD was reduced when treated with pro-, para-, and mixed biotics containing probiotics and parabiotics.

The Effect of Polynucleotide-Hyaluronic Acid Hydrogel in the Recovery After Mechanical Skin Barrier Disruption.

BACKGROUND: The epidermal barrier acts as a defense against external agents as well as helps to maintain body homeostasis. Polynucleotides (PN), exogenous DNA fragments, promote wound repair through their stimulatory and anti-inflammatory effects. Recent findings indicate a synergistic effect of PN and hyaluronic acid (HA) combinations in regulating inflammation and promoting cell proliferation. This study aims to elucidate the effects of PN and HA on repairing the epidermal barrier following its disruption by tape stripping (TS) in a mouse model. MATERIALS AND METHODS: After disrupting the epidermal barrier using TS, a formulation containing PN (14 mg/mL) and HA (6 mg/mL) was applied. Trans-epidermal water loss (TEWL) was measured at 0, 3, 6, 24, 48, and 72 h. Mice were euthanized after the final application at 72 h, and tissue samples were analyzed for epidermal/dermal thickness, neutrophil infiltration, and filaggrin expression. RESULTS: We observed a significant reduction in TEWL in the PN+HA group compared to that in the control group (20.8 ± 0.5 vs. 43.7 ± 0.5 g/m2h at 72 h, p < 0.05), indicating an improvement in barrier function. Histological evaluation showed decreased epidermal and dermal thickening in the PN+HA group compared to that in the control group (epidermal: 29.4 ± 2.2 vs. 57.9 ± 3.5 µm; dermal: 464.8 ± 25.9 vs. 825.9 ± 44.8 µm, both p < 0.05). Additionally, neutrophil infiltration in the dermis was significantly reduced, and filaggrin protein levels were significantly higher in the PN+HA group compared to those in the control group (4.8 ± 0.4 vs. 21.1 ± 3.3 for neutrophils; 0.84 ± 0.04 vs. 0.42 ± 0.03 for filaggrin, both p < 0.05). CONCLUSION: These results suggest that PN+HA may be an effective therapeutic strategy for repairing skin barrier damage.

Human Placenta Extract (HPH) Suppresses Inflammatory Responses in TNF-α/IFN-γ-Stimulated HaCaT Cells and a DNCB Atopic Dermatitis (AD)-Like Mouse Model.

Atopic dermatitis (AD), a chronic inflammatory disease, severely interferes with patient life. Human placenta extract (HPH; also known as human placenta hydrolysate) is a rich source of various bioactive substances and has widely been used to dampen inflammation, improve fatigue, exert anti-aging effects, and promote wound healing. However, information regarding HPH's incorporation in AD therapies is limited. Therefore, this study aimed to evaluate HPH's effective potential in treating AD using tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated human keratinocytes (HaCaT), immunized splenocytes, and a 2,4-dinitrochlorobenzene (DNCB)-induced AD mouse model. In TNF-α /IFN-γ-stimulated HaCaT cells, HPH markedly reduced the production of reactive oxygen species (ROS) and restored the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), superoxide dismutase 1(SOD1), catalase, and filaggrin (FLG). HPH reduced interleukin (IL)-6; thymus- and activation-regulated chemokine (TARC); thymic stromal lymphopoietin (TSLP); and regulated upon activation, normal T cell expressed and presumably secreted (RANTES) levels and inhibited nuclear factor kappa B phosphorylation. Additionally, HPH suppressed the T helper 2 (Th2) immune response in immunized splenocytes. In the AD-like mouse model, it significantly mitigated the DNCB-induced elevation in infiltrating mast cells and macrophages, epidermal thickness, and AD symptoms. HPH also reduced TSLP levels and prevented FLG downregulation. Furthermore, it decreased the expression levels of IL-4, IL-5, IL-13, TARC, RANTES, and immunoglobulin E (IgE) in serum and AD-like skin lesion. Overall, our findings demonstrate that HPH effectively inhibits AD development and is a potentially useful therapeutic agent for AD-like skin disease.

Benvitimod upregulates filaggrin, involucrin and loricrin expressions via aryl hydrocarbon receptor-OVO-like 1 axis.

Benvitimod has been successfully used in the treatment of psoriasis and atopic dermatitis (AD). However, the mechanism remains to be clarified. We aim to assess the effects of benvitimod on MC903-induced dermatitis in mice and to investigate the effects of benvitimod on filaggrin (FLG), involucrin (IVL), and loricrin (LOR) expressions and possible mechanism. MC903-induced mouse AD model was used to evaluate the effects of benvitimod. Filaggrin, involucrin, and loricrin protein and mRNA expressions in lesions of mice dermatitis were measured by Western blot and quantitative real-time PCR. In vitro, normal human epidermal keratinocytes (NHEKs) were cultured and benvitimod was used to treat NHEKs primed with IL-4 and IL-13. Then AHR and OVOL1 in NHEKs were knocked down to evaluate the role of AHR and OVOL1 in the effects of benvitimod. Topical treatment of benvitimod repaired skin barrier and alleviated skin inflammation in mouse AD model. This effect was inhibited by pretreatment with an AHR antagonist. Benvitimod upregulated the filaggrin, involucrin, and loricrin expressions in lesions of mouse AD model. In addition, benvitimod upregulated the filaggrin, involucrin, and loricrin expressions in NHEKs. Knockdown of AHR or OVO-like (OVOL)1 abrogated the upregulation of filaggrin, involucrin, and loricrin induced by benvitimod. Benvitimod attenuated MC903-induced mouse dermatitis and upregulated filaggrin, involucrin, and loricrin expressions via AHR-OVOL1 axis.

Novel three-dimensional live skin-like in vitro composite for bioluminescence reporter gene assay.

We genetically manipulated HaCaT cells, a spontaneously immortalised normal keratinocyte cell line, to stably express two different coloured luciferase reporter genes, driven by interleukin 8 (IL-8) and ubiquitin-C (UBC) promoters, respectively. Subsequently, we generated a three-dimensional (3D) skin-like in vitro composite (SLIC) utilising these cells, with the objective of monitoring bioluminescence emitted from the SLIC. This SLIC was generated on non-woven silica fibre membranes in differentiation medium. Immunohistochemical analyses of skin differentiation markers in the SLIC revealed the expression of keratins 2 and 10, filaggrin, and involucrin, indicating mature skin characteristics. This engineered SLIC was employed for real-time bioluminescence monitoring, allowing the assessment of time- and dose-dependent responses to UV stress, as well as to hydrophilic and hydrophobic chemical loads. Notably, evaluation of responses to hydrophobic substances has been challenging with conventional 2D cell culture methods, suggesting the need for a new approach, which this technology could address. Our observations suggest that engineered SLIC with constitutively expressing reporters driven by selected promoters which are tailored to specific objectives, significantly facilitates assays exploring the physiological functions of skin cells based on genetic response mechanisms. It also highlights new avenues for evaluating the physiological impacts of various compounds designed for topical application to human skin.

The human retroviral-like aspartic protease 1 (ASPRV1): From in vitro studies to clinical correlations.

The human retroviral-like aspartic protease 1 (ASPRV1) is a retroviral-like protein that was first identified in the skin due to its expression in the stratum granulosum layer of the epidermis. Accordingly, it is also referred to as skin-specific aspartic protease. Similar to the retroviral polyproteins, the full-length ASPRV1 also undergoes self-proteolysis, the processing of the precursor is necessary for the autoactivation of the protease domain. ASPRV1's functions are well-established at the level of the skin: it is part of the epidermal proteolytic network and has a significant contribution to skin moisturization via the limited proteolysis of filaggrin; it is only natural protein substrate identified so far. Filaggrin and ASPRV1 are also specific for mammalians, these proteins provide unique features for the skins of these species, and the importance of filaggrin processing in hydration is proved by the fact that some ASPRV1 mutations are associated with skin diseases such as ichthyosis. ASPRV1 was also found to be expressed in macrophage-like neutrophil cells, indicating that its functions are not limited to the skin. In addition, differential expression of ASPRV1 was detected in many diseases, with yet unknown significance. The currently known enzymatic characteristics-that had been revealed mainly by in vitro studies-and correlations with pathogenic phenotypes imply potentially important functions in multiple cell types, which makes the protein a promising target of functional studies. In this review we describe the currently available knowledge and future perspective in regard to ASPRV1.

Investigation of transcriptional and immunological disparities among patient groups with varied prognostic risk factors in cholangiocarcinoma.

BACKGROUND: This study explores molecular features associated with better prognosis in cholangiocarcinoma (CCA). METHODS AND RESULTS: The transcriptomic and whole-exome sequencing data obtained from paired tissues of 70 were analyzed, grouping them based on progression-free survival (PFS), differentiation degree, and lymph node metastasis. Among the 70 patients, the TP53 gene mutation frequency was the highest (53%), while FLG gene mutation occurred exclusively in the long PFS group. In the comparison between long and short survival groups, the short PFS group exhibited higher monocyte infiltration levels (p = 0.0287) and upregulation of genes associated with cancer-related transcriptional misregulation, chemokine signaling, and cytokine-cytokine receptor interactions. Differences in immune cell infiltration and gene expression were significant across differentiation and lymph node metastasis groups. Particularly noteworthy was the marked increase in CD8 T cell and NK cell infiltration (p = 0.0291, 0.0459) in the lymph node metastasis group, significantly influences prognosis. Additionally, genes related to platinum resistance, Th17 cell differentiation, and Th1 and Th2 cell differentiation pathways were overexpressed in this group. In summary, higher monocyte infiltration levels in the short PFS group, along with elevated expression of genes associated with cancer-related pathways, suggest a poorer prognosis. The significant increase in CD8 T cell and NK cell infiltration reflects an enhanced anti-tumor immune response, underscoring the relevance of immune infiltration levels and gene expression in predicting outcomes for CCA patients. CONCLUSIONS: In this study, we elucidated the pertinent molecular mechanisms and pathways that influence the prognosis of CCAs through comprehensive multi-omics analysis.

Protein degradation in the stratum corneum.

The stratum corneum (SC), the outermost epidermal layer, plays a pivotal role in skin barrier function. This review delves into the intricate process of protein degradation within the stratum corneum, elucidating the roles of specific enzymes, regulatory mechanisms and the consequent impact on various skin conditions. Protein degradation is a finely tuned process, orchestrated by a suite of proteolytic enzymes like kallikreins. These enzymes are responsible for the breakdown of corneodesmosomes and the orderly desquamation of corneocytes, a process essential for skin homeostasis. Another critical enzymatic process is the breakdown of proteins like filaggrin and the generation of amino acids and their derivatives, required in the physiological water-handling properties of the SC. Regulation of these proteolytic activities is complex, involving a balance between endogenous inhibitors and other factors like pH, hydration and environmental stressors. Dysregulation of protease activity is linked to a spectrum of skin conditions, ranging from xerosis to inflammatory diseases like atopic dermatitis and psoriasis. Aberrant protein degradation can lead to compromised skin barrier function, increased tissue water loss and heightened susceptibility to infections and allergens. Understanding the factors affecting protein degradation can inform the development of targeted skincare products. Advances in biochemistry and dermatology have paved the way for the search for active ingredients designed to modulate protease activity. Such innovations may offer promising therapeutic avenues for enhancing skin barrier function and treating skin disorders. This review underscores the significance of enzymatic protein degradation in the SC and its regulatory mechanisms. It provides insights into the pathophysiology of skin diseases and outlines the potential for novel skincare interventions. By bridging the gap between fundamental research and practical applications, this article aims to inspire further investigation for better understanding of skin physiology and innovation in the realm of skincare product development.

La couche cornée (stratum corneum, SC), la couche épidermique la plus externe, joue un rôle essentiel dans la fonction de barrière cutanée. Cette revue se penche sur le processus complexe de dégradation des protéines au sein de la couche cornée, ce qui explique les rôles des enzymes spécifiques, les mécanismes de régulation et l'impact qui en résulte sur diverses affections cutanées. La dégradation des protéines est un processus subtil, orchestré par une série d'enzymes protéolytiques telles que les kallikréines. Ces enzymes sont responsables de la décomposition des cornéodesmosomes et de la desquamation ordonnée des cornéocytes, un processus essentiel à l'homéostasie de la peau. Un autre processus enzymatique essentiel est la dégradation des protéines telles que la filaggrine et la génération d'acides aminés et de leurs dérivés, nécessaires aux propriétés physiologiques de traitement de l'eau de la SC. La régulation de ces activités protéolytiques est complexe, impliquant un équilibre entre les inhibiteurs endogènes et d'autres facteurs tels que le pH, l'hydratation et les facteurs de stress environnementaux. Le dérèglement de l'activité de la protéase est lié à un spectre d'affections cutanées, allant de la xérose à des maladies inflammatoires telles que la dermatite atopique et le psoriasis. Une dégradation aberrante des protéines peut compromettre la fonction de barrière cutanée, augmenter la perte d'eau tissulaire et augmenter la sensibilité aux infections et aux allergènes. Comprendre les facteurs affectant la dégradation des protéines peut contribuer au développement de produits de soins de la peau ciblés. Les progrès en biochimie et en dermatologie ont ouvert la voie à la recherche de principes actifs conçus pour moduler l'activité de la protéase. Ces innovations peuvent offrir des pistes thérapeutiques prometteuses pour améliorer la fonction de la barrière cutanée et traiter les troubles cutanés. Cette revue souligne l'importance de la dégradation enzymatique des protéines dans la SC et ses mécanismes de régulation. Elle fournit des informations sur la physiopathologie des maladies cutanées et souligne le potentiel de nouvelles interventions pour soins de la peau. En comblant le fossé entre la recherche fondamentale et les applications pratiques, cet article vise à inspirer des recherches supplémentaires pour mieux comprendre la physiologie de la peau et l'innovation dans le domaine du développement de produits de soins de la peau.

Symmetrical acral keratoderma associated with new variants in the filaggrin gene.

Symmetrical acral keratoderma (SAK) is a rare skin disorder with symmetric hyperkeratotic patches on the acral regions. Variants in the filaggrin gene (FLG) have been associated with SAK since 2020. To explore the clinical and genetic basis in six patients with SAK. Whole-exome sequencing, direct sequencing, and prediction of protein structure and function were performed. In this study, we identified two novel variants, c.3320del and c.4909del, and seven previously reported variants, c.3099C>G, c.4544C>A, c.6950_6957del, c.7264G>T, c.7945del, c.8117C>G, c.12064A>T. The findings of this study bolster the existing evidence implicating FLG variants in SAK, introducing two novel variants to the database of FLG variants associated with the condition.

Evaluation of the anti-aging potential of acetyl tripeptide-30 citrulline in cosmetics.

Acetyl tripeptide-30 citrulline, a commercialized bio-active peptide, is widely used in anti-wrinkle formulations. Volunteer-based tests have demonstrated that topical application of products containing acetyl tripeptide-30 citrulline significantly reduces the visibility of stretch marks. However, there is still a lack of research dedicated to systematically and holistically evaluating its cosmetic properties and elucidating its mechanisms of action. In this study, we assessed the cosmetic potential of acetyl tripeptide-30 citrulline using human immortalized keratinocytes (HaCaT) and mouse embryonic fibroblasts (3T3). Our findings reveal that acetyl tripeptide-30 citrulline exhibits anti-inflammatory and antioxidant activities in skin cells, particularly effective against the inflammatory markers cyclooxygenase-2 (COX2), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6), and the extent of inhibition of reactive oxygen species (ROS) production ranged from 95 % to 340 %. Moreover, acetyl tripeptide-30 citrulline specifically up-regulates Collagen IV and down-regulates matrix metalloproteinase-9 (MMP9), enhances the expression of skin barrier proteins transglutaminase 1 (TGM1) and filaggrin (FLG), thereby demonstrating its reparative capabilities. Additionally, acetyl tripeptide-30 citrulline increases the expression of the water channel protein aquaporin 3 (AQP3), thus improving skin hydration function. These results substantiate the previously proclaimed cosmetic attributes of acetyl tripeptide-30 citrulline and support its efficacy as an anti-aging agent in dermatological applications.

Restoration of Skin Barrier Abnormalities with IL4/13 Inhibitors and Jak Inhibitors in Atopic Dermatitis: A Systematic Review.

Background and Objectives: Atopic dermatitis is a chronic inflammatory skin disorder with a significant burden on patients' quality of life. This systematic review aims to evaluate the restoration of skin barrier abnormalities with interleukin-4/interleukin-13 (IL-4/IL-13) inhibitors and Janus kinase (JAK) inhibitors in atopic dermatitis. Materials and Methods: A comprehensive review of the literature was conducted, focusing on studies that assess the use of IL-4/IL-13 inhibitors and JAK inhibitors for atopic dermatitis. We identified eligible studies by searching Medline via PubMed with a special focus on their effect on the restoration of the epidermal barrier. Included studies evaluated the transepidermal water loss (TEWL), the reduction in epidermal thickness (ET), the improvement in ceramide synthesis, and the increase in stratum corneum hydration (SCH) with IL-4/IL-13 inhibitors and JAK inhibitors. The quality of included studies was assessed using the ROBINS-I and the RoB 2.0 tool for assessing the risk of bias. Results: Ten of the included studies concern dupilumab, while two concern JAK inhibitors. Ten were observational studies and two were randomized controlled trials (RCTs). The total number of included participants was 378 concerning dupilumab and 38 concerning JAK inhibitors. Five studies did not include any comparison group, three included healthy volunteers, two were conducted versus placebo, and two compared dupilumab with other treatments. The follow-up period ranged between 29 days and 32 weeks. The results demonstrated a significant decrease in transepidermal water loss (TEWL) and an increase in SCH on eczematous lesions for patients with sustained response to dupilumab treatment and observed improvements in ET and filaggrin (FLG) staining, which further support the efficacy of JAK inhibitors in enhancing skin barrier function. Conclusions: This review underscores the efficacy of IL-4/IL-13 inhibitors in improving skin barrier function. However, the limited number of studies focusing on JAK inhibitors and the overall lack of RCTs highlight the need for further research to establish the definitive role of IL-4/IL-13 inhibitors and JAK inhibitors in the restoration of the skin barrier.

Mechanisms for initiation of food allergy by skin pre-disposed to atopic dermatitis.

Food allergy can be life-threatening and often develops early in life. In infants and children, loss-of-function mutations in skin barrier genes associate with food allergy. In a mouse model with skin barrier mutations (Flakey Tail, FT+/- mice), topical epicutaneous sensitization to a food allergen peanut extract (PNE), an environmental allergen Alternaria alternata (Alt) and a detergent induce food allergy and then an oral PNE-challenge induces anaphylaxis. Exposures to these allergens and detergents can occur for infants and children in a household setting. From the clinical and preclinical studies of neonates and children with skin barrier mutations, early oral exposure to allergenic foods before skin sensitization may induce tolerance to food allergens and thus protect against development of food allergy. In the FT+/- mice, oral food allergen prior to skin sensitization induce tolerance to food allergens. However, when the skin of FT+/- pups are exposed to a ubiquitous environmental allergen at the time of oral consumption of food allergens, this blocks the induction of tolerance to the food allergen and the mice can then be skin sensitized with the food allergen. The development of food allergy in neonatal FT+/- mice is mediated by altered skin responses to allergens with increases in skin expression of interleukin 33, oncostatin M and amphiregulin. The development of neonate food allergy is enhanced when born to an allergic mother, but it is inhibited by maternal supplementation with α-tocopherol. Moreover, preclinical studies suggest that food allergen skin sensitization can occur before manifestation of clinical features of atopic dermatitis. Thus, these parameters may impact design of clinical studies for food allergy, when stratifying individuals by loss of skin barrier function or maternal atopy before offspring development of atopic dermatitis.

Transdermal delivery of elastin peptide assisted by betaine-based deep eutectic solvent to ameliorate skin photoaging.

The unique amino acid composition of elastin peptide (EP) makes it an excellent resource to obtain antioxidant peptides. It exhibits high elastase inhibitory activity with the potential to resist skin aging and is currently used in a many cosmetic products. However, the inherent low permeability of the skin limits its ability to penetrate the skin. To address this issue, a deep eutectic solvent (SAB) with excellent bioactivity was synthesized from betaine and succinic acid and used as a permeation enhancer to improve the absorption and utilization of EP in this paper. The results showed that low SAB concentrations significantly increased the transdermal delivery of EP. The 3D epidermal skin model (EpiKutis®) demonstrated that SAB/EP induced the synthesis of hyaluronic acid (HA) and filaggrin (FLG), accelerated skin barrier repair, and reduced water loss. Additionally, the zebrafish embryonic model showed that SAB/EP could reduce melanin secretion, decrease melanin deposition, and have an ameliorative effect on skin photoaging. Cellular experiments proved that SAB/EP can stimulate human skin fibroblasts to secrete procollagen I and elastin, improving skin elasticity and anti-wrinkle. The combination of EP and DES is a new attempt that is expected to be used as a safe and effective anti-wrinkle cosmetic material.

Early-life risk factors which govern pro-allergic immunity.

Allergic diseases affect up to 40% of the global population with a substantial rise in food allergies, in particular, over the past decades. For the majority of individuals with allergy fundamental programming of a pro-allergic immune system largely occurs in early childhood where it is crucially governed by prenatal genetic and environmental factors, including their interactions. These factors include several genetic aberrations, such as filaggrin loss-of-function mutations, early exposure to respiratory syncytial virus, and various chemicals such as plasticizers, as well as the influence of the gut microbiome and numerous lifestyle circumstances. The effects of such a wide range of factors on allergic responses to an array of potential allergens is complex and the severity of these responses in a clinical setting are subsequently not easy to predict at the present time. However, some parameters which condition a pro-allergic immune response, including severe anaphylaxis, are becoming clearer. This review summarises what we currently know, and don't know, about the factors which influence developing pro-allergic immunity particularly during the early-life perinatal period.

Large-scale whole-exome sequencing analyses identified protein-coding variants associated with immune-mediated diseases in 350,770 adults.

The genetic contribution of protein-coding variants to immune-mediated diseases (IMDs) remains underexplored. Through whole exome sequencing of 40 IMDs in 350,770 UK Biobank participants, we identified 162 unique genes in 35 IMDs, among which 124 were novel genes. Several genes, including FLG which is associated with atopic dermatitis and asthma, showed converging evidence from both rare and common variants. 91 genes exerted significant effects on longitudinal outcomes (interquartile range of Hazard Ratio: 1.12-5.89). Mendelian randomization identified five causal genes, of which four were approved drug targets (CDSN, DDR1, LTA, and IL18BP). Proteomic analysis indicated that mutations associated with specific IMDs might also affect protein expression in other IMDs. For example, DXO (celiac disease-related gene) and PSMB9 (alopecia areata-related gene) could modulate CDSN (autoimmune hypothyroidism-, psoriasis-, asthma-, and Graves' disease-related gene) expression. Identified genes predominantly impact immune and biochemical processes, and can be clustered into pathways of immune-related, urate metabolism, and antigen processing. Our findings identified protein-coding variants which are the key to IMDs pathogenesis and provided new insights into tailored innovative therapies.

Melanin accumulation in acanthotic seborrheic keratosis: Reduced proliferation and early differentiation of keratinocytes and increased number of melanocytes.

Seborrheic keratosis (SK) is a common benign tumour, often associated with hyperpigmentation. To investigate the mechanism of melanin accumulation in SK, we have conducted comprehensive gene expression and histological analyses. We obtained five pairs of skin samples, including non-lesional and SK samples, from the backs of three male Japanese participants aged 40-59 years. To examine melanocytes and keratinocytes in SK, three pairs of skin samples were separated by laser capture microdissection into the basal layer and the other layer in the epidermis. We performed a comprehensive gene expression analysis to identify differentially expressed genes between non-lesional and SK skin, followed by gene ontology and pathway analysis. We found abnormal morphogenesis and cell proliferation in the basal layer, along with increased immune response and impaired cell differentiation and metabolism in the other layer of SK. We focused on cell proliferation and differentiation, as these are directly associated with melanin accumulation. Immunohistochemical analyses of Ki67, keratin 10, and keratin 14 demonstrated the decreases in the proliferation and early differentiation of the epidermis. Contrarily, no significant changes were observed in terminal differentiation markers, filaggrin and loricrin. Although the number of melanocytes was higher in SK than in non-lesional skin, melanogenic activity showed no difference. These results indicated that melanin accumulation in SK is caused by delayed melanin excretion due to reduced turnover around the basal and spinous layers of the epidermis and melanin production due to an increased number of melanocytes. Our findings provide new insights for therapeutic approaches in SK.

Mutational and transcriptional profile predicts the prognosis of stage IV gastric cancer - Prognostic factors for metastatic gastric cancer.

BACKGROUND AND STUDY AIMS: The clinicopathological risk factors in the prognosis of stage IV gastric cancer have been comprehensively studied. However, the influencing factors of stage IV gastric cancer prognosis at genomic and transcriptional levels have not been well defined. PATIENTS AND METHODS: The mutational and transcriptional data, along with demographic, clinicopathological and prognostic information of 44 stage IV gastric cancer patients were downloaded from the TCGA database. Univariate and multivariate analyses were performed to identify the significant risk factors and a Nomogram model was established to predict the patient prognosis. RESULTS: TTN, TP53, FLG, LRP1B, SYNE1 and ARID1A were among the top mutated genes without hot-spot mutations. The mutational status of AHNAK2, ASCC3, DNAH3, DOP1A, MYLK, SIPA1L1, SORBS2, SYNE1 and ANF462 significantly stratified the patient prognosis. The transcription of several genes, such as AQP10, HOXC8/9/10, COL10A1/COL11A1, WNT7B, KRT17 and KLK6 was significantly up-regulated or down-regulated. Enrichment analysis on mutations and transcription revealed cell skeleton and membrane function, extracellular matrix function, HPV infection, and several cancer-related pathways as the main aberrancies. Univariate analyses revealed a series of significant factors stratifying patient prognosis, mainly including cancer location, several mutated genes and many up- or down-regulated genes. However, subsequent multivariate analysis revealed SYNE1 mutation, DNAH3 mutation, COMMD3 transcription level, and cancer location as the independent risk factors. A Nomogram model has been established with these significant risk factors to predict the patient prognosis. Further validation is needed to ensure the effectiveness of the model in real clinical practice. CONCLUSIONS: Cancer location, along with the mutational status of SYNE1 and DNAH3 and the transcriptional level of COMMD3 were independent risk factors of stage IV gastric cancer. A Nomogram model was established with these factors for prognosis prediction.

Study of Genetic Mutations and Their Association With the Development of Atopic Dermatitis and Other Skin Diseases.

The purpose of this study was to identify the heterogeneity of atopic dermatitis and to identify key genetic factors. This can lead to new approaches and personalized treatment strategies. I conducted a literature review of three scientific publication platforms (i.e., PubMed, Cochrane Library, Scopus) for records published between July 2011 and July 2023 using key words related to the genetics of atopic dermatitis. The high heritability and genetic pleiotropia of atopic dermatitis emphasize the importance of its genetic predisposition and interaction with concomitant diseases. The study also shows the role of various genes associated with immunity and inflammatory reactions, as well as the high heritability of atopic dermatitis, particularly among twins. Genetic mutations, specifically polymorphisms of genes encoding immune factors and inflammatory responses, determine an individual's predisposition to atopic dermatitis. Research findings also point to genetic aspects associated with other skin conditions such as psoriasis and vitiligo, confirming the existence of common genetic mechanisms between these diseases. Specifically, polymorphisms of the filaggrin gene have been found to be key genetic determinants of atopic dermatitis. I analyzed the genetic basis of atopic dermatitis, emphasizing the importance of genetic determinants and their interaction with the immune system and extracellular matrix. This study contributes to the understanding of the mechanisms of atopic dermatitis and opens new perspectives for individualized treatments.