Molecular evidence for multiple origins and high genetic differentiation of non-native winter crane fly, Trichocera maculipennis (Diptera: Trichoceridae), in the maritime Antarctic.

Native biodiversity and ecosystems of Antarctica safeguarded from biological invasion face recent threats from non-native species, accelerated by increasing human activities and climate changes. Over two decades ago, the winter crane fly, Trichocera maculipennis, was first detected on King George Island. It has now successfully colonized several research stations across King George Island. To understand the origin, genetic diversity, and population structure of this Holarctic species, we conducted mitochondrial DNA cytochrome c oxidase subunit I (COI) sequence analysis across both its native and invasive ranges. In parallel, we performed microsatellite loci analysis within the invasive ranges, utilizing 12 polymorphic microsatellite markers. Furthermore, we compared body sizes among adult males and females collected from three different locations of King George Island. Our COI sequence analysis exhibited two different lineages present on King George Island. Lineage I was linked to Arctic Svalbard and Polish cave populations and Lineage II was related to Canadian Terra Nova National Park populations, implying multiple origins. Microsatellite analysis further exhibited high levels of genetic diversity and significant levels of genetic differentiation among invasive populations. Body sizes of adult T. maculipennis were significantly different among invasive populations but were not attributed to genetics. This significant genetic diversity likely facilitated the rapid colonization and establishment of T. maculipennis on King George Island, contributing to their successful invasion. Molecular analysis results revealed a substantial amount of genetic variation within invasive populations, which can serve as management units for invasive species control. Furthermore, the genetic markers we developed in the study will be invaluable tools for tracking impending invasion events and the travel routes of new individuals. Taken together, these findings illustrate the highly invasive and adaptable characteristics of T. maculipennis. Therefore, immediate action is necessary to mitigate their ongoing invasion and facilitate their eradication.

Recombinant Lignin Peroxidase with Superior Thermal Stability and Melanin Decolorization Efficiency in a Typical Human Skin-Mimicking Environment.

Recently, the desire for a safe and effective method for skin whitening has been growing in the cosmetics industry. Commonly used tyrosinase-inhibiting chemical reagents exhibit side effects. Thus, recent studies have focused on performing melanin decolorization with enzymes as an alternative due to the low toxicity of enzymes and their ability to decolorize melanin selectively. Herein, 10 different isozymes were expressed as recombinant lignin peroxidases (LiPs) from Phanerochaete chrysosporium (PcLiPs), and PcLiP isozyme 4 (PcLiP04) was selected due to its high stability and activity at pH 5.5 and 37 °C, which is close to human skin conditions. In vitro melanin decolorization results indicated that PcLiP04 exhibited at least 2.9-fold higher efficiency than that of well-known lignin peroxidase (PcLiP01) in a typical human skin-mimicking environment. The interaction force between melanin films measured by a surface forces apparatus (SFA) revealed that the decolorization of melanin by PcLiP04 harbors a disrupted structure, possibly interrupting π-π stacking and/or hydrogen bonds. In addition, a 3D reconstructed human pigmented epidermis skin model showed a decrease in melanin area to 59.8% using PcLiP04, which suggests that PcLiP04 exhibits a strong potential for skin whitening.

Dermatobacter hominis gen. nov., sp. nov., a new member of the family Iamiaceae, revealed the potential utilisation of skin-derived metabolites.

A non-motile, novel actinobacterial strain, Kera-3T, which is a gram-positive, aerobic, rod-shaped bacterium, was isolated from human keratinocytes on 1/10 diluted R2A agar. Whole-cell hydrolysis of amino acids revealed the presence of meso-DAP, alanine, and glutamic acid. The predominant menaquinone was MK-9 (H8), whereas the primary fatty acids were C16:0 and C18:1 ω9c. The major phospholipids included diphosphatidylglycerol and aminophospholipids, along with an unidentified phosphoglycolipid and an aminophosphoglycolipid. The G+C content of the genomic DNA was 73.2%, based on the complete genome sequence. Phylogenetic analyses of the 16S rRNA gene sequence and phylogenomic analysis of 91 core genes showed that strain Kera-3T formed a new lineage in the family Iamiaceae, with the closest neighbour Rhabdothermincola sediminis SYSU G02662T having 91.19% 16S rRNA gene sequence identity. A comparative genomic study of the predicted general metabolism and carbohydrate-active enzymes supported the phylogenetic and phylogenomic data. Based on the analysis of physiological, biochemical, and genomic characteristics, strain Kera-3T can be distinguished from known genera in the family Iamiaceae and represents a novel genus and species. Therefore, the name Dermatobacter hominis gen. nov., sp. nov. was proposed, with the type strain Kera-3T (= KACC 22415T = LMG 32493T).

A novel sophorolipids extraction method by yeast fermentation process for enhanced skin efficacy.

AIMS: Oriental herbs have been used as medicines in the folk remedy for their numerous phytochemicals and bioactivities. In this study, we have selected five Korean traditional medical herbs and applied bio conversion extraction technology, named it as Bioconversion Oji complex, to identify phytochemicals and evaluate skin related efficacies. MATERIAL AND METHODS: The process of two-step bio conversion was sequentially conducted. The first step of fermentation was to produce biosurfactants using macadamia seed oil with Candida bombicola, and then five natural plants were added to carry out the main fermentation. To evaluate skin improvement efficacy of Bioconversion Oji complex, in vitro and in vivo studies were conducted. We studied HaCaT cells cultured to assess viability, skin anti-inflammatory, moisturizing and barrier improvement-related mRNA expression. For efficacy study, 21 participants were tested evaluating anti-inflammatory, skin moisturizing and skin barrier improving effects of Bioconversion Oji complex compared to Water extraction of Oji (placebo) for the 4 weeks test period. RESULTS: The application of bioconversion technology highly increased the content of amino acids and lipids within Bioconversion Oji complex, and 23 flavonoids were also identified. Bioconversion Oji complex was found to be non-toxic and showed significant effects in all parameters tested, including anti-inflammation, skin moisture, and skin barrier in both in vitro and in clinical studies. CONCLUSIONS: Bioconversion Oji complex has demonstrated skin-friendly properties with significant beneficial effects on anti-inflammatory, skin hydration and barrier function properties. This study provides evidence for the use of Bioconversion Oji complex as an active ingredient in cosmetics and skincare products.

Physiological and molecular responses of the Antarctic harpacticoid copepod Tigriopus kingsejongensis to salinity fluctuations - A multigenerational study.

Since Antarctica and the surrounding Southern Ocean are facing global climate change, biota inhabiting those coastal regions is now challenged by environmental fluctuations including coastal freshening. In this study, the effects of salinity range of 0-75 (practical salinity unit, PSU) on the Antarctic harpacticoid copepod Tigriopus kingsejongensis was investigated by measurement of 96 h survival rate, lifespan, and sex ratio with further analysis of multigenerational growth parameters and mRNA expressions under salinity of 15-45. Different stages of the copepods (i.e., nauplius, male, and female) generally showed tolerance to hypo- and hypersalinity, wherein female copepods were more tolerant than males when exposed to salinity fluctuations. Lifespan was significantly shortened by hypo- and hypersalinity compared to control salinity (34), but there was no significant difference in the sex ratio between salinity treatments. Multigenerational experiments across five generations revealed that exposure to salinities of 15 and 45 reduced body length compared to that in control salinity and the first generation of each salinity group. Our results provide evidence regarding T. kingsejongensis on their preferred salinity ranges, physiological limit to salinity fluctuations, and population dynamics in future salinity.

Caviar Extract and Its Constituent DHA Inhibits UVB-Irradiated Skin Aging by Inducing Adiponectin Production.

In this study, caviar (sturgeon eggs) was used to elucidate its roles in adiponectin production and skin anti-aging. Recently, caviar has been largely used not only as a nutritional food, but also in cosmetic products. In particular, it has been reported that docosahexaenoic acid (DHA), as one of the main phospholipid components of caviar extract, induces intracellular lipid accumulation and the expression of adiponectin in adipocytes. Although adipocytes are well known to be associated with the skin dermis by secreting various factors (e.g., adiponectin), the effects of caviar extract and DHA on the skin are not well studied. Here, we demonstrate the effects of caviar extract and DHA on adipocyte differentiation and adiponectin production, resulting in a preventive role in UV-irradiated skin aging. Caviar extract and DHA enhanced adipocyte differentiation and promoted the synthesis of transcription factors controlling adipocyte differentiation and adiponectin. In addition, the mRNA expression levels of matrix metalloproteinase-1 (MMP-1) were decreased in UVB-irradiated Hs68 fibroblasts that were cultured in conditioned medium from caviar extract or DHA-treated differentiated adipocytes. Taken together, these results indicate that caviar extract and DHA induce adipocyte differentiation and adiponectin production, thereby inhibiting UVB-induced premature skin aging via the suppression of MMP-1 production.

Synthesis of Kisspeptin-Mimicking Fragments and Investigation of their Skin Anti-Aging Effects.

In recent years, a number of active materials have been developed to provide anti-aging benefits for skin and, among them, peptides have been considered the most promising candidate due to their remarkable and long-lasting anti-wrinkle activity. Recent studies have begun to elucidate the relationship between the secretion of emotion-related hormones and skin aging. Kisspeptin, a neuropeptide encoded by the KISS1 gene, has gained attention in reproductive endocrinology since it stimulates the reproductive axis in the hypothalamus; however, the effects of Kisspeptin on skin have not been studied yet. In this study, we synthesized Kisspeptin-10 and Kisspeptin-E, which are biologically active fragments, to mimic the action of Kisspeptin. Next, we demonstrated the anti-aging effects of the Kisspeptin-mimicking fragments using UV-induced skin aging models, such as UV-induced human dermal fibroblasts (Hs68) and human skin explants. Kisspeptin-E suppressed UV-induced 11 beta-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) stimulation leading to a regulation of skin aging related genes, including type I procollagen, matrix metalloproteinases-1 (MMP-1), interleukin-6 (IL-6), and IL-8, and rescued the skin integrity. Taken together, these results suggest that Kisspeptin-E could be useful to improve UV-induced skin aging by modulating expression of stress related genes, such as 11ß-HSD1.

Type II Ice-Binding Proteins Isolated from an Arctic Microalga Are Similar to Adhesin-Like Proteins and Increase Freezing Tolerance in Transgenic Plants.

Microalgal ice-binding proteins (IBPs) in the polar region are poorly understood at the genome-wide level, although they are important for cold adaptation. Through the transcriptome study with the Arctic green alga Chloromonas sp. KNF0032, we identified six Chloromonas IBP genes (CmIBPs), homologous with the previously reported IBPs from Antarctic snow alga CCMP681 and Antarctic Chloromonas sp. They were organized with multiple exon/intron structures and low-temperature-responsive cis-elements in their promoters and abundantly expressed at low temperature. The biological functions of three representative CmIBPs (CmIBP1, CmIBP2 and CmIBP3) were tested using in vitro analysis and transgenic plant system. CmIBP1 had the most effective ice recrystallization inhibition (IRI) activities in both in vitro and transgenic plants, and CmIBP2 and CmIBP3 had followed. All transgenic plants grown under nonacclimated condition were freezing tolerant, and especially 35S::CmIBP1 plants were most effective. After cold acclimation, only 35S::CmIBP2 plants showed slightly increased freezing tolerance. Structurally, the CmIBPs were predicted to have ß-solenoid forms with parallel ß-sheets and repeated TXT motifs. The repeated TXT structure of CmIBPs appears similar to the AidA domain-containing adhesin-like proteins from methanogens. We have shown that the AidA domain has IRI activity as CmIBPs and phylogenetic analysis also supported that the AidA domains are monophyletic with ice-binding domain of CmIBPs, and these results suggest that CmIBPs are a type of modified adhesins.

Complete genome sequencing of Shigella sp. PAMC 28760: Identification of CAZyme genes and analysis of their potential role in glycogen metabolism for cold survival adaptation.

Shigella sp. PAMC 28760 (isolated from Himantormia sp. lichen in Antarctica) is a gram-negative, non-sporulating bacterium that has cellulolytic and amylolytic characteristics as well as glycogen metabolic pathways. In this study, we isolated S. sp. PAMC 28760 from Antarctic lichen, and present the complete genome sequence with annotations describing its unique features. The genome sequence has 58.85% GC content, 4,278 coding DNA sequences, 85 tRNAs, and 22 rRNA operons. 16S rRNA gene sequence analyses revealed strain PAMC 28760 as a potentially new species of genus Shigella, showing various differences from pathogenic bacteria reported previously. dbCAN2 analyses revealed 91 genes related to carbohydrate-metabolizing enzymes. S. sp. PAMC 28760 likely degrades polysaccharide starch to obtain glucose for energy conservation. This study provides a foundation for understanding Shigella survival adaptation mechanisms under extremely cold Antarctic conditions.

2'-Fucosyllactose Attenuates Particulate Matter-Induced Inflammation via Inhibition of Hypoxia-Inducible Factor in Keratinocytes.

2'-Fucosyllactose (2FL) is the most abundant component of the oligosaccharide content in human milk. It has been reported that 2FL has the ability to protect against infectious disease caused by bacterial pathogens. In this study, we investigated the protective effects of 2FL on particulate matter (PM)10-induced pro-inflammatory cytokines in HaCaT keratinocytes. 2FL reduced PM10-induced excess expression of interleukin (IL)-6, IL-8, IL-1α and IL-1ß in HaCaT keratinocytes. In addition, PM10 also increased hypoxia-inducible factor (HIF)-1α protein levels; however, 2FL inhibited the accumulation of HIF-1α protein and the phosphorylation of phosphatidylinositol 3-kinase (PI3K)/Akt stimulated by PM10. Furthermore, 2FL improved PM10-induced the decrease in epidermal thickness and integrity of the cornified layer in the reconstructed human epidermal skin model (RHE). In our results, 2FL inhibited PM10-induced pro-inflammatory mediators by regulating the HIF-1α/PI3K/Akt pathway and protected the skin epidermis against PM10 irritation. Taken together, these results suggest that 2FL can be used as a primary ingredient in cosmeceutical products to alleviate skin irritation and inflammation caused by urban air pollution.

Epidermidibacterium keratini gen. nov., sp. nov., a member of the family Sporichthyaceae, isolated from keratin epidermis.

A novel actinobacterial strain, designated EPI-7T, was isolated on R2A agar from human skin (keratinocytes) and subjected to a taxonomic study using a polyphasic approach. Strain EPI-7T showed a Gram-positive reaction, was non-motile, non-spore-forming, and cells had a rod-shape. Colonies were round, convex and pale yellow. Phylogenetic analysis based on 16S rRNA gene sequences showed that the novel isolate formed a cluster with several uncultured bacterial clones and with cultured members of the genera Modestobacter and Sporichthya. The 16S rRNA gene sequence similarities with respect to the type strains of recognized species from the above genera and other phylogenetic neighbours ranged from 92.6 to 93.4 %. The G+C content of the genomic DNA was 68.9 mol%. The only isoprenoid quinone was MK-9(H4), and the major fatty acids detected were C17 : 1ω8c, C16 : 0, iso-C15 : 0 and summed feature 3. The major polar lipids were found to be phosphatidylethanolamine, phosphatidylinositol, three unidentified phospholipids, phosphatidylglycerol, phosphatidylcholine, two unidentified amino lipids and three unidentified lipids. The cell-wall peptidoglycan contained meso-diaminopimelic acid, glutamic acid and alanine. Whole-cell sugars present included rhamnose, glucose and galactose. The combination of the genotypic and phenotypic data allowed differentiation of strain EPI-7T from its closest phylogenetic neighbours and provided evidence that strain EPI-7T represents a novel genus and species in the family Sporichthyaceae. The name Epidermidibacterium keratini gen. nov., sp. nov. is proposed with the type strain being EPI-7T (=KCCM 90264T=JCM 31644T).

De novo transcriptome assembly of brackish water flea Diaphanosoma celebensis based on short-term cadmium and benzo[a]pyrene exposure experiments.

To develop a brackish water flea as a promising model for marine monitoring, Diaphanosoma celebensis were exposed to two pollutants, cadmium (Cd) and benzo[a]pyrene (BaP), which have different chemical characteristics and distinct modes of metabolic action on aquatic animals. Twenty-four hours after exposure to Cd (2 mg/L) or BaP (25 µg/L), whole body transcriptomes were analyzed. In total, 99.6 Mbp were assembled from nine libraries, resulting in 98,458 transcripts with an N50 of 1883 bp and an average contig length of 968 bp. Functional gene annotations were performed using Gene Ontology, Eukaryotic Orthologous Groups, and Kyoto Encyclopedia of Genes and Genomes pathway analyses. Cd significantly modulated endocrine and digestive enzyme system. Following BaP treatment, DNA repair and circadian rhythm related metabolisms were significantly modulated. Both the chemicals induced stress response and detoxification metabolism. This brackish water flea genomic information will be useful to monitor estuaries and coastal regions, as water fleas have been confirmed as promising sentinel models in freshwater ecosystems.

Polyphenol-rich apple extract inhibits dexamethasone-induced sebaceous lipids production by regulating SREBP1 expression.

Sebum production and excretion is a primary function of the sebaceous glands, but abnormally increased sebum production is a major cause of acne vulgaris. To identify a new candidate that regulates sebum production, we investigated the possible inhibitory effects of apple polyphenols (APP) purified from unripe apples on primary cultured human sebocytes and in patients with acne vulgaris. Dexamethasone (Dex) increased lipid synthesis and expression of the sterol response element-binding protein 1 (SREBP 1) and its target enzymes, acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), in the sebocytes. However, APP inhibited Dex-induced lipid production and expression of SREBP-1, ACC and FAS. APP also inhibited the increase in the expression and activation of glucocorticoid receptor in the sebocytes. Taken together, these results suggest that APP may be useful to regulate sebum production and may alleviate sebum-involved skin disease, such as acne vulgaris.

Ultraviolet- and infrared-induced 11 beta-hydroxysteroid dehydrogenase type 1 activating skin photoaging is inhibited by red ginseng extract containing high concentration of ginsenoside Rg3(S).

BACKGROUND: Sun irradiation is one of major extrinsic stressors responsible for premature skin aging through activation and expression of 11 beta-hydroxysteroid dehydrogenase type 1 (11ß-HSD1), which converts inactive cortisone to active cortisol. The aim of this study was to evaluate the inhibitory effects of red ginseng extract containing high concentrations of ginsenoside Rg3 (S) (GERg3) on 11ß-HSD1-induced skin photoaging. METHODS: To evaluate the inhibitory effects of GERg3 on ultraviolet- (UV) or infrared (IR)-induced skin photoaging, human dermal fibroblasts or a normal human 3D skin model was exposed to UV or an IR. RT-PCR, ELISA, Western blot, and H&E staining were used for evaluations. GERg3 was isolated from crude red ginseng. RESULTS: GERg3 inhibited the increased expressions of 11ß-HSD1, interleukin (IL)-6, and matrix metalloproteinase-1 (MMP-1) in UVB- or IR-exposed Hs68 cells. Additionally, the increased cortisol, IL-6, and MMP-1 expressions were effectively reduced by GERg3 in UVA-exposed 3D skin models. The photoinduced decrease in type 1 procollagen also recovered as a result of GERg3 treatment in Hs68 cells and the 3D skin model. In addition, the UVA-exposed dermal thickness was decreased in comparison with the UVA-protected 3D skin model, recovered with GERg3 treatment. CONCLUSION: GERg3 had antiphotoaging effects in UV- or IR-exposed human dermal fibroblasts and normal human 3D skin model.

Changes in trust and the use of Korean medicine in South Korea: a comparison of surveys in 2011 and 2014.

BACKGROUND: Korean medicine (KM) has been widely used in Korea. This study aimed to assess the general perceptions of KM, to investigate the patterns of its usage in 2014, and to compare the results with those of an earlier survey from 2011. METHODS: A cross-sectional study was conducted with 1000 Korean people. The questionnaire included items regarding trust in KM, reasons for distrust of KM, and visit frequency to KM clinics. This study used methods consistent with those of a 2011 survey to examine changes in attitudes over 3 years. RESULTS: Despite high rates of trust in KM, the visit frequency decreased from 69.3% in 2011 to 63.2% in 2014. Usage among young adults (in their 20s and 30s) was significantly reduced compared to all other age groups. The KM modality most commonly used by participants was acupuncture, whereas the use of moxibustion and cupping therapies has decreased since 2011. Men and women were most likely to distrust KM due to a "lack of scientific evidence" (59.3%) and "suspicion of KM safety" (47.4%), respectively. CONCLUSIONS: The findings suggested that KM use and trust in KM were slightly lower in 2014 than in 2011. The decreases were most notable among individuals in their 30s and in the use of moxibustion in KM therapy. This study aimed to produce practical insights by reviewing patterns of KM use and perceptions over time. Additional surveys must be considered to produce a more in-depth analysis.

Transcriptome analysis of immune response genes induced by pathogen agonists in the Antarctic bullhead notothen Notothenia coriiceps.

Fish are a representative population of lower vertebrates that serve as an essential link to early vertebrate evolution, and this has fueled academic interest in studying ancient vertebrate immune defense mechanisms in teleosts. Notothenia coriiceps, a typical Antarctic notothenioid teleost, has evolved to adapt to the cold and thermally stable Antarctic sea. In this study, we examined adaptive signaling pathways and immune responses to bacterial and viral pathogenic exposure in N. coriiceps. Using RNA sequencing, we investigated transcriptional differences in the liver tissues of N. coriiceps challenged with two pathogen-mimicking agonists, a bacterial ligand (heat-killed Escherichia coli, HKEB) and a viral ligand (polyinosinic:polycytidylic acid, Poly I:C). We found that 567 unique genes were up-regulated two-fold in the HKEB-exposed group, whereas 392 unique genes, including 124 immune-relevant genes, were up-regulated two-fold in the Poly I:C-exposed group. A KEGG pathway analysis of the 124 immune-relevant genes revealed that they exhibited major features of antigen processing and presentation bacterial ligand exposure, but they were down-regulated after viral ligand exposure. A quantitative real time RT-PCR analysis revealed that TNFα and TNF2, major inducers of apoptosis, were highly up-regulated after exposure to the viral ligand but not the bacterial ligand. The results suggest that the bacterial and viral ligands up-regulate inducers of different immune mechanisms in N. coriiceps liver tissue. N. coriiceps has an immune response defense strategy that uses antigen presentation against bacterial infection, but it may use a different defense, such as TNF-mediated apoptosis, against viral infection. The specific immune responses of N. coriiceps may be adaptations to the Antarctic environment and pathogens. These results will help define the characteristics of Antarctic fish and increase our understanding of their immune response mechanisms.

Population Genetic Structure of the Malaria Vector Anopheles sinensis (Diptera: Culicidae) Sensu Stricto and Evidence for Possible Introgression in the Republic of Korea.

Anopheles sinensis Wiedemann sensu stricto (s.s.) is a dominant mosquito and considered a secondary malaria vector in the Republic of Korea (ROK). Despite the potential significance for malaria control, population genetics studies have been conducted using only mitochondrial DNA (mtDNA), and studies of the genetics of hybridization have never been attempted. In this study, 346 specimens from 23 localities were subject to experiments. Among them, 305 An. sinensis s.s. specimens from 20 localities were used for mtDNA analysis, and 346 specimens comprising 341 An. sinensis s.s. from 22 localities and five Anopheles kleini Rueda from one locality were examined in the microsatellite study. Neighbor-joining analysis of pairwise FST and RST based on microsatellite results showed that the populations are divided into two groups, as did the mtDNA results. However, the Bayesian analysis and factorial correspondence analysis plots showed three distinct clusters. Among the mtDNA and microsatellite results, only microsatellites represented small but positive and significant isolation-by-distance patterns. Both molecular markers show the Taebaek and Sobaek Mountain ranges as barriers between the northern and southern parts of the ROK. The newly recognized third group suggests possible introgressive hybridization of An. sinensis s.s. with closely related species. The slightly different composition of populations in each group based on different markers is probably because of different population dynamics in each group. These results imply that there is restricted gene flow of epidemiologically important malaria-related genes between the northern and southern parts of the ROK.

Skin benefits of postbiotics derived from Micrococcus luteus derived from human skin: an untapped potential for dermatological health.

BACKGROUND: The skin microbiome, a diverse community of microorganisms, plays a crucial role in maintaining skin health. Among these microorganisms, the gram-positive bacterium Micrococcus luteus exhibits potential for promoting skin health. This study focuses on postbiotics derived from M. luteus YM-4, a strain isolated from human skin. OBJECTIVE: Our objective is to explore the beneficial effects of YM-4 culture filtrate on dermatological health, including enhancing barrier function, modulating immune response, and aiding recovery from environmental damage. METHODS: The effects of the YM-4 culture filtrate were tested on human keratinocytes and fibroblasts under various conditions using real-time PCR for gene expression analysis and fibroblast migration assays. A dehydration-simulated model was employed to prepare RNA-Seq samples from HaCaT cells treated with the YM-4 culture filtrate. Differentially expressed genes were identified and functionally classified through k-means clustering, gene ontology terms enrichment analyses, and protein-protein interactions mapping. RESULTS: The YM-4 culture filtrate enhanced the expression of genes involved in skin hydration, hyaluronic acid synthesis, barrier function, and cell proliferation. It also reduced inflammation markers in keratinocytes and fibroblasts under stress conditions. It mitigated UVB-induced collagen degradation while promoted collagen synthesis, suggesting anti-aging properties, and accelerated wound healing processes by promoting cell proliferation and migration. RNA sequencing analysis revealed that the YM-4 culture filtrate could reverse dehydration-induced transcriptional changes towards a state similar to untreated cells. CONCLUSION: M. luteus YM-4 culture filtrate exhibits significant therapeutic potential for dermatological applications.