Ampelopsin facilitates diabetic wound healing and keratinocyte cell progression by inhibiting the NLRP3 inflammasome pathway in macrophages.

Ampelopsin (AMP) had a wound-healing effect in rat skin wounds with or without purulent infection. However, the role of AMP in diabetic wound healing remains poorly defined. Wounds were created on the dorsal skin of type 2 diabetic mouse model, and the histological features of wounds were examined by hematoxylin and eosin (HE) staining. Caspase-1 activity and the secretion of inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). Cell viability and migration were examined through cell counting kit-8 (CCK-8) and wound healing assays, respectively. AMP facilitated wound healing in vivo. AMP notably facilitated platelet endothelial cell adhesion molecule-31 (CD31), collagen type I alpha 1 chain (COL1A1), and alpha-smooth muscle actin (α-SMA), and inhibited matrix metallopeptidase 9 (MMP9) and cyclooxygenase 2 (Cox2) expression in diabetic wounds. The inflammasome pathway was implicated in skin injury. AMP inhibited pro-inflammatory factor secretions and NLR family pyrin domain containing 3 (NLRP3) inflammasome pathway in diabetic wounds and high glucose-treated THP-1 macrophages. AMP-mediated NLRP3 inflammasome inhibition in THP-1 macrophages increased cell viability and migratory capacity in HaCaT cells. AMP facilitated diabetic wound healing and increased keratinocyte cell viability and migratory ability by inhibiting the NLRP3 inflammasome pathway in macrophages.

Anti-Photodamage Effect of Agaricus blazei Murill Polysaccharide on UVB-Damaged HaCaT Cells.

UVB radiation is known to induce photodamage to the skin, disrupt the skin barrier, elicit cutaneous inflammation, and accelerate the aging process. Agaricus blazei Murill (ABM) is an edible medicinal and nutritional fungus. One of its constituents, Agaricus blazei Murill polysaccharide (ABP), has been reported to exhibit antioxidant, anti-inflammatory, anti-tumor, and immunomodulatory effects, which suggests potential effects that protect against photodamage. In this study, a UVB-induced photodamage HaCaT model was established to investigate the potential reparative effects of ABP and its two constituents (A1 and A2). Firstly, two purified polysaccharides, A1 and A2, were obtained by DEAE-52 cellulose column chromatography, and their physical properties and chemical structures were studied. A1 and A2 exhibited a network-like microstructure, with molecular weights of 1.5 × 104 Da and 6.5 × 104 Da, respectively. The effects of A1 and A2 on cell proliferation, the mitochondrial membrane potential, and inflammatory factors were also explored. The results show that A1 and A2 significantly promoted cell proliferation, enhanced the mitochondrial membrane potential, suppressed the expression of inflammatory factors interleukin-1ß (IL-1ß), interleukin-8 (IL-8), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α), and increased the relative content of filaggrin (FLG) and aquaporin-3 (AQP3). The down-regulated JAK-STAT signaling pathway was found to play a role in the response to photodamage. These findings underscore the potential of ABP to ameliorate UVB-induced skin damage.

Investigation into the Anti-Acne Effects of Castanea sativa Mill Leaf and Its Pure Ellagitannin Castalagin in HaCaT Cells Infected with Cutibacterium acnes.

Acne vulgaris is a prevalent skin disorder affecting many young individuals, marked by keratinization, inflammation, seborrhea, and colonization by Cutibacterium acnes (C. acnes). Ellagitannins, known for their antibacterial and anti-inflammatory properties, have not been widely studied for their anti-acne effects. Chestnut (Castanea sativa Mill., C. sativa), a rich ellagitannin source, including castalagin whose acne-related bioactivity was previously unexplored, was investigated in this study. The research assessed the effect of C. sativa leaf extract and castalagin on human keratinocytes (HaCaT) infected with C. acnes, finding that both inhibited IL-8 and IL-6 release at concentrations below 25 µg/mL. The action mechanism was linked to NF-κB inhibition, without AP-1 involvement. Furthermore, the extract displayed anti-biofilm properties and reduced CK-10 expression, indicating a potential role in mitigating inflammation, bacterial colonization, and keratosis. Castalagin's bioactivity mirrored the extract's effects, notably in IL-8 inhibition, NF-κB inhibition, and biofilm formation at low µM levels. Other polyphenols, such as flavonol glycosides identified via LC-MS, might also contribute to the extract's biological activities. This study is the first to explore ellagitannins' potential in treating acne, offering insights for developing chestnut-based anti-acne treatments pending future in vivo studies.

[Effects of gelatin methacrylate anhydride hydrogel loaded with small extracellular vesicles derived from human umbilical cord mesenchymal stem cells in the treatment of full-thickness skin defect wounds in mice].

Objective: To investigate the effects of gelatin methacrylate anhydride (GelMA) hydrogel loaded with small extracellular vesicles derived from human umbilical cord mesenchymal stem cells (hUCMSCs-sEVs) in the treatment of full-thickness skin defect wounds in mice. Methods: This study was an experimental study. hUCMSCs-sEVs were extracted by ultracentrifugation, their morphology was observed through transmission electron microscope, and the expression of CD9, CD63, tumor susceptibility gene 101 (TSG101), and calnexin was detected by Western blotting. The human umbilical vein endothelial cells (HUVECs), the 3rd and 4th passages of human epidermal keratinocytes (HEKs) and human dermal fibroblasts (HDFs) were all divided into blank control group (routinely cultured) and hUCMSC-sEV group (cultured with the cell supernatant containing hUCMSCs-sEVs). The cell scratch test was performed and the cell migration rates at 6, 12, and 24 h after scratching were calculated, the cell Transwell assay was performed and the number of migration cells at 12 h after culture was calculated, and the proportion of proliferating cells was detected by 5-acetylidene-2'-deoxyuridine and Hoechst staining at 24 h after culture, with sample numbers being all 3. The simple GelMA hydrogel and the GelMA hydrogel loaded with hUCMSCs-sEVs (hereinafter referred to as hUCMSC-sEV/GelMA hydrogel) were prepared. Then the micromorphology of 2 kinds of hydrogels was observed under scanning electron microscope, the distribution of hUCMSCs-sEVs was observed by laser scanning confocal microscope, and the cumulative release rates of hUCMSCs-sEVs at 0 (immediately), 2, 4, 6, 8, 10, and 12 d after soaking hUCMSC-sEV/GelMA hydrogel in phosphate buffer solution (PBS) were measured and calculated by protein colorimetric quantification (n=3). Twenty-four 6-week-old male C57BL/6J mice were divided into PBS group, hUCMSC-sEV alone group, GelMA hydrogel alone group, and hUCMSC-sEV/GelMA hydrogel group according to the random number table, with 6 mice in each group, and after the full-thickness skin defect wounds on the back of mice in each group were produced, the wounds were performed with PBS injection, hUCMSC-sEV suspenson injection, simple GelMA coverage, and hUCMSC-sEV/GelMA hydrogel coverage, respectively. Wound healing was observed on post injury day (PID) 0 (immediately), 4, 8, and 12, and the wound healing rates on PID 4, 8, and 12 were calculated, and the wound tissue was collected on PID 12 for hematoxylin-eosin staining to observe the structure of new tissue, with sample numbers being both 6. Results: The extracted hUCMSCs-sEVs showed a cup-shaped structure and expressed CD9, CD63, and TSG101, but barely expressed calnexin. At 6, 12, and 24 h after scratching, the migration rates of HEKs (with t values of 25.94, 20.98, and 20.04, respectively), HDFs (with t values of 3.18, 5.68, and 4.28, respectively), and HUVECs (with t values of 4.32, 19.33, and 4.00, respectively) in hUCMSC-sEV group were significantly higher than those in blank control group (P<0.05). At 12 h after culture, the numbers of migrated HEKs, HDFs, and HUVECs in hUCMSC-sEV group were 550±23, 235±9, and 856±35, respectively, which were significantly higher than 188±14, 97±6, and 370±32 in blank control group (with t values of 22.95, 23.13, and 17.84, respectively, P<0.05). At 24 h after culture, the proportions of proliferating cells of HEKs, HDFs, and HUVECs in hUCMSC-sEV group were significantly higher than those in blank control group (with t values of 22.00, 13.82, and 32.32, respectively, P<0.05). The inside of simple GelMA hydrogel showed a loose and porous sponge-like structure, and hUCMSCs-sEVs was not observed in it. The hUCMSC-sEV/GelMA hydrogel had the same sponge-like structure, and hUCMSCs-sEVs were uniformly distributed in clumps. The cumulative release rate curve of hUCMSCs-sEVs from hUCMSC-sEV/GelMA hydrogel tended to plateau at 2 d after soaking, and the cumulative release rate of hUCMSCs-sEVs was (59.2±1.8)% at 12 d after soaking. From PID 0 to 12, the wound areas of mice in the 4 groups gradually decreased. On PID 4, 8, and 12, the wound healing rates of mice in hUCMSC-sEV/GelMA hydrogel group were significantly higher than those in the other 3 groups (P<0.05); the wound healing rates of mice in GelMA hydrogel alone group and hUCMSC-sEV alone group were significantly higher than those in PBS group (P<0.05). On PID 8 and 12, the wound healing rates of mice in hUCMSC-sEV alone group were significantly higher than those in GelMA hydrogel alone group (P<0.05). On PID 12, the wounds of mice in hUCMSC-sEV/GelMA hydrogel group showed the best wound epithelization, loose and orderly arrangement of dermal collagen, and the least number of inflammatory cells, while the dense arrangement of dermal collagen and varying degrees of inflammatory cell infiltration were observed in the wounds of mice in the other 3 groups. Conclusions: hUCMSCs-sEVs can promote the migration and proliferation of HEKs, HDFs, and HUVECs which are related to skin wound healing, and slowly release in GelMA hydrogel. The hUCMSC-sEV/GelMA hydrogel as a wound dressing can significantly improve the healing speed of full-thickness skin defect wounds in mice.

Geniposide alleviates imiquimod-induced psoriasis-like skin lesions in mice via inhibition of angiogenesis.

In this study, we aimed to evaluate the protective effect of geniposide (GEN) on imiquimod (IMQ)-induced psoriasis-like skin lesions in mice. Firstly, visual changes of psoriatic skin lesions were observed and the severity was recorded using psoriasis area and severity index (PASI) score. Histological changes were assessed by HE staining for epidermal thickness and Masson's staining for collagen fibers. Then, photographs of microvascular inside the skin were taken for macroscopic observation, and microscopic changes associated with angiogenesis were evaluated. Furthermore, expression of angiogenic factors were analyzed by ELISA, immunohistochemistry and immunofluorescence, separately. Lastly, the expression of VEGFR signaling-related proteins was detected by WB. Compared with control, IMQ drove a significant increment of epidermal thicknesses with higher PASI scores and more dermal collagen deposition. IMQ treatment led to abnormal keratinocyte proliferation, increased microvascular inside skin, growing production of angiogenesis-related factors, up-regulated expression of VEGFR1 and VEGFR2, and enhanced phosphorylation of p38. However, GEN significantly ameliorated the psoriatic skin lesions, the epidermal thickness, the formation of collagen fibers, and abnormal keratinocyte proliferation. Importantly, GEN inhibited angiogenesis, the production of angiogenic factors (VEGF-A, Ang-2, TNF-α, and IL-17A), and the proliferation of vascular endothelial cells. Simultaneously, GEN curbed the expression of VEGFR1, VEGFR2, p38, and P-p38 proteins involved in VEGFR signaling. Of note, the suppressive effect of GEN was reversed in the HUVECs with over-expressed VEGFR1 or VEGFR2 related to the cells without transfection. These findings suggest that VEGFR1 and VEGFR2 participate in the anti-angiogenesis of GEN in IMQ-induced psoriasis-like skin lesions in mice.

Formononetin attenuates psoriasiform inflammation by regulating interferon signaling pathway.

BACKGROUND: Psoriasis is a long-lasting, inflammatory, continuous illness caused through T cells and characterized mainly by abnormal growth and division of keratinocytes. Currently, corticosteroids are the preferred option. However, prolonged use of traditional topical medication can lead to adverse reactions and relapse, presenting a significant therapeutic obstacle. Improved alternative treatment options are urgently required. Formononetin (FMN) is a representative component of isoflavones in Huangqi (HQ) [Astragalus membranaceus (Fisch.) Bge.]. It possesses properties that reduce inflammation, combat oxidation, inhibit tumor growth, and mimic estrogen. Although FMN has been shown to ameliorate skin barrier devastation via regulating keratinocyte apoptosis and proliferation, there are no reports of its effectiveness in treating psoriasis. OBJECTIVE: Through transcriptomics clues and experimental investigation, we aimed to elucidate the fundamental mechanisms underlying FMN's action on psoriasis. MATERIALS AND METHODS: Cell viability was examined using CCK8 assay in this study. The results of analysis of differentially expressed genes (DEGs) between FMN-treated HaCaT cells and normal HaCaT cells using RNA-sequencing (RNA-seq) were presented on volcano plots and heatmap. Enrichment analysis was conducted on DEGs using Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO), and results were validated through RT-qPCR verification. After 12 days of FMN treatment in psoriasis mouse model, we gauged the PASI score and epidermis thickness. A variety of techniques were used to assess FMN's effectiveness on inhibiting inflammation and proliferation related to psoriasis, including RT-qPCR, HE staining, western blot, and immunohistochemistry (IHC). RESULTS: The findings indicated that FMN could suppress the growth of HaCaT cells using CCK8 assay (with IC50 = 40.64 uM) and 20 uM FMN could reduce the level of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) to the greatest extent. FMN-treated HaCaT cells exhibited 985 up-regulated and 855 down-regulated DEGs compared to normal HaCaT cells. GO analysis revealed that DEGs were linked to interferon (IFN) signaling pathway. Furthermore, FMN improved pathological features, which encompassed decreased erythema, scale, and thickness scores of skin lesions in psoriasis mouse model. In vivo experiments confirmed that FMN down-regulated expression of IFN-α, IFN-ß, IFN-γ, decreased secretion of TNF-α and IL-17 inflammatory factors, inhibited expression of IFN-related chemokines included Cxcl9, Cxcl10, Cxcl11 and Cxcr3 and reduced expression of transcription factors p-STAT1, p-STAT3 and IFN regulatory factor 1 (IRF1) in the imiquimod (IMQ) group. CONCLUSIONS: In summary, these results suggested that FMN played an anti-inflammatory and anti-proliferative role in alleviating psoriasis by inhibiting IFN signaling pathway, and FMN could be used as a potential therapeutic agent.

Salvianolic acid A prevents UV-induced skin damage by inhibiting the cGAS-STING pathway.

DNA damage resulting from UV irradiation on the skin has been extensively documented in numerous studies. In our prior investigations, we demonstrated that UVB-induced DNA breakage from keratinocytes can activate the cGAS-STING pathway in macrophages. The cGAS-STING signaling pathway serves as the principal effector for detecting and responding to abnormal double-stranded DNA in the cytoplasm. Expanding on our previous findings, we have further validated that STING knockout significantly diminishes UVB-induced skin damage, emphasizing the critical role of cGAS-STING activation in this context. Salvianolic acid A, a principal active constituent of Salvia miltiorrhiza Burge, has been extensively studied for its therapeutic effects in conditions such as coronary heart disease, angina pectoris, and diabetic peripheral neuropathy. However, its effect on cGAS-STING pathway and its ability to alleviate skin damage have not been previously reported. In a co-culture system, supernatant from UVB-treated keratinocytes induced IRF3 activation in macrophages, and this activation was inhibited by salvianolic acid A. Our investigation, employing photodamage and photoaging models, establishes that salvianolic acid A effectively mitigates UV-induced epidermal thickening and collagen degeneration. Treatment with salvianolic acid A significantly reduced skin damage, epidermal thickness increase, and keratinocyte hyperproliferation compared to the untreated photo-damage and photoaging model groups. In summary, salvianolic acid A emerges as a promising candidate for preventing UV-induced skin damage by inhibiting cGAS-STING activation. This research enhances our understanding of the intricate mechanisms underlying skin photodamage and provides a potential avenue for the development of therapeutic interventions.

Antiviral and synergistic effects of photo-energy with acyclovir on herpes simplex virus type 1 infection.

This experimental study aimed to evaluate the antiviral and synergistic effects of photoenergy irradiation on human herpes simplex virus type I (HSV-1) infection. We assessed viral replication, plaque formation, and relevant viral gene expression to examine the antiviral and synergistic effects of blue light (BL) with acyclovir treatment. Our results showed that daily BL (10 J/cm2) irradiation inhibited plaque-forming ability and decreased viral copy numbers in HSV-1-infected monkey kidney epithelial Vero cells and primary human oral keratinocyte (HOK) cells. Combined treatment with the antiviral agent acyclovir and BL irradiation increased anti-viral activity, reducing viral titers and copy numbers. In particular, accumulated BL irradiation suppressed characteristic viral genes including UL19 and US6, and viral DNA replication-essential genes including UL9, UL30, UL42, and UL52 in HOK cells. Our results suggest that BL irradiation has anti-viral and synergistic properties, making it a promising therapeutic candidate for suppressing viral infections in clinical trials.

The crude extract obtained from Cinnamomum macrostemon Hayata regulates oxidative stress and mitophagy in keratinocytes.

Four ethanol fractionated crude extracts (EFCEs [A-D]) purified from the leaves of Cinnamomum macrostemon Hayata were screened for antioxidative effects and mitochondrial function in HaCaT cells. The higher cell viability indicated that EFCE C was mildly toxic. Under the treatment of 50 ng/mL EFCE C, the hydrogen peroxide (H2O2)-induced cytosolic and mitochondrial reactive oxygen species levels were reduced as well as the H2O2-impaired cell viability, mitochondrial membrane potential (MMP), ATP production, and mitochondrial mass. The conversion of globular mitochondria to tubular mitochondria is coincident with EFCE C-restored mitochondrial function. The mitophagy activator rapamycin showed similar effects to EFCE C in recovering the H2O2-impaired cell viability, MMP, ATP production, mitochondrial mass, and also mitophagic proteins such as PINK1, Parkin, LC3 II, and biogenesis protein PGC-1α. We thereby propose the application of EFCE C in the prevention of oxidative stress in skin cells.

Protective autophagy enhances antistress ability through AMPK/ULK1 signaling pathway in human immortalized keratinocytes.

Keratinocytes, located in the outermost layer of human skin, are pivotal cells to resist environmental damage. Cellular autophagy plays a critical role in eliminating damaged organelles and maintaining skin cell homeostasis. Low-dose 5-Aminolevulinic acid photodynamic therapy (ALA-PDT) has been demonstrated to enhance skin's antistress ability; however, the regulatory mechanisms of autophagy in keratinocytes remain unclear. In this study, we treated immortalized human keratinocytes (HaCaT cells) with low-dose ALA-PDT (0.5 mmol/L, 3 J/cm2). Through RNA-sequencing analysis, we identified that low-dose ALA-PDT modulated autophagy-related pathways in keratinocytes and pinpointed Unc-51-like kinase 1 (ULK1) as a key gene involved. Western blot results revealed that low-dose ALA-PDT treatment upregulated the expression of autophagy-related proteins Beclin-1 and LC3-II/LC3-I ratio. Notably, low-dose ALA-PDT regulated autophagy by inducing an appropriate level of reactive oxygen species (ROS), transiently reducing mitochondrial membrane potential, and decreasing adenosine triphosphate production; all these processes functioned on the AMP-activated protein kinase (AMPK)/ULK1 pathway to activate autophagy. Finally, we simulated external environmental damage using ultraviolet B (UVB) at a dose of 60 mJ/cm2 and observed that low-dose ALA-PDT mitigated UVB-induced cell apoptosis; however, this protective effect was reversed when using the autophagy inhibitor 3-methyladenine. Overall, these findings highlight how low-dose ALA-PDT enhances antistress ability in HaCaT cells through controlling ROS generation and activating the AMPK/ULK1 pathway to arouse cellular autophagy.

Dendrobium officinale Polysaccharide (DOP) inhibits cell hyperproliferation, inflammation and oxidative stress to improve keratinocyte psoriasis-like state.

PURPOSE: Psoriasis is a skin disease characterized by excessive proliferation, inflammation and oxidative stress in keratinocytes. The present study aimed to investigate the therapeutic effects of Dendrobium officinale polysaccharide (DOP) on keratinocyte psoriasis-like models. METHODS: The HaCaT keratinocyte inflammation models were induced by interleukin (IL)-22 or lipopolysaccharide (LPS), respectively, and oxidative stress damage within cells was elicited by H2O2 and treated using DOP. CCK-8 and EdU were carried out to detect cell proliferation. ELISA, qRT-PCR, and Western blot were conducted to measure the expression of pro-inflammatory cytokines IL17A, IL-23, IL1ß, tumor necrosis factor alpha (TNF-α), and IL-6. Reactive oxygen species (ROS) level in keratinocytes was detected by flow cytometry. Cell proliferation-associated proteins (PCNA, Ki67, Cyclin D1) and pathway proteins (p-AKT and AKT), and oxidative stress marker proteins (Nrf-2, CAT, SOD1) were detected by Western blot. RESULT: DOP did not affect the proliferation of normal keratinocytes, but DOP was able to inhibit the proliferative activity of IL-22-induced overproliferating keratinocytes and suppress the expression of proliferation-related factors PCNA, Ki67, and Cyclin D1 as well as the proliferation pathway p-AKT. In addition, DOP treatment was able to inhibit IL-22 and LPS-induced inflammation and H2O2-induced oxidative stress, including the expression of IL17A, IL-23, IL1ß, TNF-α, IL-6, and IL1ß, as well as the expression levels of intracellular ROS levels and cellular oxidative stress-related indicators SOD, MDA, CAT, Nrf-2 and SOD1. CONCLUSION: DOP inhibits keratinocyte hyperproliferation, inflammation and oxidative stress to improve the keratinocyte psoriasis-like state.

In Vitro Anti-Inflammatory and Skin Protective Effects of Codium fragile Extract on Macrophages and Human Keratinocytes in Atopic Dermatitis.

Codium fragile has been traditionally used in oriental medicine to treat enterobiasis, dropsy, and dysuria, and it has been shown to possess many biological properties. Atopic dermatitis (AD) is one of the types of skin inflammation and barrier disruption, which leads to chronic inflammatory skin diseases. In the current investigation, the protective effects of C. fragile extract (CFE) on anti-inflammation and skin barrier improvement were investigated. In LPS-stimulated RAW 264.7 cells, nitric oxide generation and the expression levels of interleukin (IL)-1ß, IL-4, IL-6, iNOS, COX-2, and tumor necrosis factor-alpha (TNF)-α were reduced by CFE. CFE also inhibited the phosphorylation of NF-κB-p65, ERK, p-38, and JNK. Additionally, CFE showed inhibitory activity on TSLP and IL-4 expression in HaCaT cells stimulated with TNF-α/interferon-gamma (IFN-γ). Enhanced expression of factors related to skin barrier function, FLG, IVL, and LOR, was confirmed. These findings implied that CFE may be used as a therapeutic agent against AD due to its skin barrier-strengthening and anti-inflammatory activities, which are derived from natural marine products.

Astaxanthin Synergizes with Ionizing Radiation (IR) in Oral Squamous Cell Carcinoma (OSCC).

Astaxanthin (ATX) is known for its antioxidant and anti-inflammation functions yet its role in cancers requires more research. This study is aimed to reveal the potential synergetic effect of ATX with ionizing radiation (IR) in OSCC. Cell survival was measured after human OSCC cells including CAL27 and SCC9, and normal human oral keratinocytes (NHOKs) were treated with different concentrations of ATX for 24 h. Colony formation assays were performed after OSCC cells were treated with IR, ATX (20 µ M), or combined and survival fraction was analyzed. Malondialdehyde (MDA), glutathione (GSH), and intercellular iron levels were measured. Western blot method was used to measure the ferroptosis-related proteins, GPX4, SLC7A11, and ACSL4. In xenograft mice model, we evaluated the tumor volumes, tumor growth, and examined the GPX4/ACSL4 proteins in tumor tissues using Immunohistochemistry (IHC). ATX inhibited viability of OSCC cells but not NHOK. In OSCC cells, ATX further enhanced the cell death induced by IR. In addition, ATX promoted the MDA content, Iron levels but inhibited the GSH regulated by IR in cells. ATX could synergize with IR, further inhibiting GPX4, SLC7A11 and promoting ACSL4 in OSCC cells. In vivo, ATX and IR treatment inhibited OSCC tumor growth and the group with combined treatment showed the most inhibitory effect. GPX4 was inhibited by IR and further inhibited in the combined group while ACSL4 was promoted by IR and enhanced more significantly in the combined group. ATX might synergize with IR treatment in OSCC partly via ferroptosis.

Neurog1-Derived Peptides RMNE1 and DualPep-Shine Penetrate the Skin and Inhibit Melanin Synthesis by Regulating MITF Transcription.

Anti-pigmentation peptides have been developed as alternative skin-lightening agents to replace conventional chemicals that have adverse effects on the skin. However, the maximum size of these peptides is often limited by their low skin and cell penetration. To address this issue, we used our intra-dermal delivery technology (IDDT) platform to identify peptides with hypo-pigmenting and high cell-penetrating activity. Using our cell-penetrating peptides (CPPs) from the IDDT platform, we identified RMNE1 and its derivative RMNE3, "DualPep-Shine", which showed levels of α-Melanocyte stimulating hormone (α-MSH)-induced melanin inhibition comparable to the conventional tyrosinase inhibitor, Kojic acid. In addition, DualPep-Shine was delivered into the nucleus and regulated the gene expression levels of melanogenic enzymes by inhibiting the promoter activity of microphthalmia-associated transcription factor-M (MITF-M). Using a 3D human skin model, we found that DualPep-Shine penetrated the lower region of the epidermis and reduced the melanin content in a dose-dependent manner. Furthermore, DualPep-Shine showed high safety with little immunogenicity, indicating its potential as a novel cosmeceutical ingredient and anti-pigmentation therapeutic agent.

Dasatinib causes keratinocyte apoptosis via inhibiting high mobility group Box 1-mediated mitophagy.

Dasatinib, a second-generation BCR-ABL inhibitor, is currently used as first-line treatment for patients with chronic myeloid leukemia. However, dasatinib treatment increases the risk of severe cutaneous toxicity, which limits its long-term safe use in clinic. The underlying mechanism for dasatinib-induced cutaneous toxicity has not been clarified. In this study, we tested the toxicity of dasatinib on human immortal keratinocyte line (HaCaT) and normal human epidermal keratinocytes (NHEK). We found that dasatinib directly caused cytotoxicity on keratinocytes, which could be the explanation of the clinical characteristic of pathology. Mechanistically, dasatinib impaired mitophagy by downregulating HMGB1 protein level in keratinocytes, which led to the accumulation of dysfunctional mitochondria. Mitochondria-derived ROS caused DNA damage and cell apoptosis. More importantly, we confirmed that overexpression of HMGB1 could reverse dasatinib-induced keratinocyte apoptosis, and preliminarily explored the intervention effect of saikosaponin A, which could increase HMGB1 expression, on cutaneous toxicity caused by dasatinib. Collectively, our study revealed that dasatinib induced keratinocyte apoptosis via inhibiting HMGB1-mediated mitophagy and saikosaponin A could be a viable strategy for prevention of dasatinib-induced cutaneous toxicity.

Fermented Taiwanofungus camphoratus Extract Ameliorates Psoriasis-Associated Response in HaCaT Cells via Modulating NF-𝜠B and mTOR Pathways.

Psoriasis is a chronic autoimmune disease, and until now, it remains an incurable disease. Therefore, the development of new drugs or agents that ameliorate the disease will have marketing potential. Taiwanofungus camphoratus (TC) is a specific fungus in Taiwan. It is demonstrated to have anticancer, anti-inflammation, and hepatoprotective effects. However, the effects of TC fermented extract on psoriasis are under investigation. In this research, we studied the ability of TC on antioxidative activity and the efficacy of TC on interleukin-17 (IL-17A)-induced intracellular oxidative stress, inflammation-relative, and proliferation-relative protein expression in human keratinocytes. The results of a DPPH radical scavenging assay, reducing power assay, and hydroxyl peroxide inhibition assay indicated that TC has a potent antioxidant ability. Furthermore, TC could reduce IL-17A-induced intracellular ROS generation and restore the NADPH level. In the investigation of pathogenesis, we discovered TC could regulate inflammatory and cell proliferation pathways via p-IKKα/p-p65 and p-mTOR/p-p70S6k signaling pathways in human keratinocytes. In conclusion, TC showed characteristics such as antioxidant, anti-inflammatory, and anti-psoriatic-associated responses. It is expected to be developed as a candidate for oxidative-stress-induced skin disorders or psoriasis treatment.

Enhancement of keratinocyte growth factor potential in inducing adipose-derived stem cells differentiation into keratinocytes by collagen-targeting.

Different growth factors can regulate stem cell differentiation. We used keratinocyte growth factor (KGF) to direct adipose-derived stem cells (ASCs) differentiation into keratinocytes. To enhance KGF bioavailability, we targeted KGF for collagen by fusing it to collagen-binding domain from Vibrio mimicus metalloprotease (vibrioCBD-KGF). KGF and vibrioCBD-KGF were expressed in Escherichia coli and purified to homogeneity. Both proteins displayed comparable activities in stimulating proliferation of HEK-293 and MCF-7 cells. vibrioCBD-KGF demonstrated enhanced collagen-binding affinity in immunofluorescence and ELISA. KGF and vibrioCBD-KGF at different concentrations (2, 10, and 20 ng/ml) were applied for 21 days on ASCs cultured on collagen-coated plates. Keratinocyte differentiation was assessed based on morphological changes, the expression of keratinocyte markers (Keratin-10 and Involucrin), and stem cell markers (Collagen-I and Vimentin) by real-time PCR or immunofluorescence. Our results indicated that the expression of keratinocyte markers was substantially increased at all concentrations of vibrioCBD-KGF, while it was observed for KGF only at 20 ng/ml. Immunofluorescence staining approved this finding. Moreover, down-regulation of Collagen-I, an indicator of differentiation commitment, was more significant in samples treated with vibrioCBD-KGF. The present study showed that vibrioCBD-KGF is more potent in inducing the ASCs differentiation into keratinocytes compared to KGF. Our results have important implications for effective skin regeneration using collagen-based biomaterials.

Untargeted metabolomics of human keratinocytes reveals the impact of exposure to 2,6-dichloro-1,4-benzoquinone and 2,6-dichloro-3-hydroxy-1,4-benzoquinone as emerging disinfection by-products.

INTRODUCTION: The 2,6-dichloro-1,4-benzoquinone (DCBQ) and its derivative 2,6-dichloro-3-hydroxy-1,4-benzoquinone (DCBQ-OH) are disinfection by-products (DBPs) and emerging pollutants in the environment. They are considered to be of particular importance as they have a high potential of toxicity and they are likely to be carcinogenic. OBJECTIVES: In this study, human epidermal keratinocyte cells (HaCaT) were exposed to the DCBQ and its derivative DCBQ-OH, at concentrations equivalent to their IC20 and IC50, and a study of the metabolic phenotype of cells was performed. METHODS: The perturbations induced in cellular metabolites and their relative content were screened and evaluated through a metabolomic study, using 1H-NMR and MS spectroscopy. RESULTS: Changes in the metabolic pathways of HaCaT at concentrations corresponding to IC20 and IC50 of DCBQ-OH involved the activation of cell membrane α-linolenic acid, biotin, and glutathione and deactivation of glycolysis/gluconeogenesis at IC50. The changes in metabolic pathways at IC20 and IC50 of DCBQ were associated with the activation of inositol phosphate, pertaining to the transfer of messages from the receptors of the membrane to the interior as well as with riboflavin. Deactivation of biotin metabolism was recorded, among others. The cells exposed to DCBQ exhibited a concentration-dependent decrease in saccharide concentrations. The concentration of steroids increased when cells were exposed to IC20 and decreased at IC50. Although both chemical factors stressed the cells, DCBQ led to the activation of transporting messages through phosphorylated derivatives of inositol. CONCLUSION: Our findings provided insights into the impact of the two DBPs on human keratinocytes. Both chemical factors induced energy production perturbations, oxidative stress, and membrane damage.

Sesquiterpenoids from Seriphidium transiliense and Their Melanogenic Activity.

A sesquiterpenoid with an unprecedented 5/5/4 tricyclic skeleton (1), a nor-sesquiterpenoid with a rare 6/7 bicyclic skeleton (2), 10 new sesquiterpenoids (3-12), and six known analogues (13-18) were isolated from the whole plants of Seriphidium transiliense. The structures of compounds 1-12 were elucidated by spectroscopic data analysis. Compound 7 showed melanogenic promotion activity in murine melanoma (B16) cells more potent than the positive control used, 8-methoxypsoralen (8-MOP). Further mechanistic studies indicated that compound 7 promotes melanogenesis through activating the transcription of microphthalmia-associated transcription factor (MITF) and tyrosinase family genes in B16 cells. Moreover, compound 7 also inhibited the expression of IFN-γ-chemokine through the JAK/STAT signaling pathway in immortalized human keratinocyte (HaCaT) cells. These results suggest that the sesquiterpenoid 7 shows potential activity for treating vitiligo.

FRA1:c-JUN:HDAC1 complex down-regulates filaggrin expression upon TNFα and IFNγ stimulation in keratinocytes.

Filaggrin (FLG), an essential structural protein for skin barrier function, is down-regulated under chronic inflammatory conditions, leading to disruption of the skin barrier. However, the detailed molecular mechanisms of how FLG changes in the context of chronic inflammation are poorly understood. Here, we identified the molecular mechanisms by which inflammatory cytokines inhibit FLG expression in the skin. We found that the AP1 response element within the -343/+25 of the FLG promoter was necessary for TNFα + IFNγ-induced down-regulation of FLG promoter activity. Using DNA affinity precipitation assay, we observed that AP1 subunit composition binding to the FLG promoter was altered from c-FOS:c-JUN (at the early time) to FRA1:c-JUN (at the late time) in response to TNFα + IFNγ stimulation. Knockdown of FRA1 or c-JUN abrogated TNFα + IFNγ-induced FLG suppression. Histone deacetylase (HDAC) 1 interacted with FRA1:c-JUN under TNFα + IFNγ stimulation. Knockdown of HDAC1 abrogated the inhibitory effect of TNFα + IFNγ on FLG expression. The altered expression of FLG, FRA1, c-JUN, and HDAC1 was confirmed in mouse models of 2,4-dinitrochlorobenzene-induced atopic dermatitis and imiquimod-induced psoriasis. Thus, the current study demonstrates that TNFα + IFNγ stimulation suppresses FLG expression by promoting the FRA1:c-JUN:HDAC1 complex. This study provides insight into future therapeutic strategies targeting the FRA1:c-JUN:HDAC1 complex to restore impaired FLG expression in chronic skin inflammation.