Mouse Skin Tissue Research Articles

Acufection-Mediated Delivery of Immune-Related Genes into Mouse Skin Tissues

Acufection-Mediated Delivery of Immune-Related Genes into Mouse Skin Tissues

Amygdalin ameliorates alopecia areata on C3H/HeJ mice by inhibiting inflammation through JAK2/STAT3 pathway

BackgroundEvidence has demonstrated that Chinese medicine formula Xuefu Zhuyu decoction can markedly promote the formation of new hair in patients and mice with alopecia areata (AA). Amygdalin is one of the active components of Xuefu Zhuyu decoction, but its therapeutic effects and the underlying mechanisms on AA remains largely unrevealed. PurposeTherefore, this study aims to investigate the therapeutic effects and to probe its molecular mechanisms of inflammation and immune regulation on AA model of C3H/HeJ mice. Study designThe C3H/HeJ female mice were divided into control, AA, rusolitinib (60 mg/kg), and amygdalin groups (60, 90, and 120 mg/kg, 0.2 ml/10 g, i.g.). MethodsThe optical microscope was used to observe the feature of the local skin, and the number of lanugo and terminal hair. H&E staining was performed to determine the degree of pathological damage to the skin. ELISA was performed to detect levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in mice serum. Flow cytometry was carried out to analyze the CD4+CD25+FOXP3+, CD4+ and CD8+ of skin tissue. And the levels of CD4+ and CD8+, p-JAK/JAK2, p-STAT3/STAT, and SOCS3 were detected by immunohistochemistry. Western blot and qRT-PCR were employed to examine the expression levels of IL-6, TNF-α, IFN-γ, JAK2, p-JAK, STAT, p-STAT3 and SOCS3 proteins and genes in skin tissues. ResultsCompared with AA group, amygdalin immensely increased the number of vellus hairs and decreased the number of terminal hairs determined by skin microscopy and H&E staining. ELISA, Western blot and qRT-PCR data showed that the levels of IL-6, TNF-α and IFN-γ in serum and skin tissues of AA mice were significantly increased, while amygdalin administration dramatically restrained the contents of the three pro-inflammatory factors. Flow cytometry and immunohistochemistry hinted that amygdalin observably enhanced the number of CD4+CD25+FOXP3+ and CD4+ cells, while inhibited the number of CD8+ positive cells in mice with AA. Moreover, amygdalin signally reduced JAK2/STAT3 pathway-related protein and gene levels in AA mice. ConclusionAmygdalin could inhibit inflammatory response and improve immune function in the treatment of AA. The underlying molecular mechanism may be related to inhibition of JAK2/STAT3 pathway.

Effect of Chloroquine on Type 2 Inflammatory Response in MC903-Induced Atopic Dermatitis Mice.

Atopic dermatitis (AD) is a chronic, non-infectious inflammatory dermatosis. Chloroquine (CQ) has long been proven to possess anti-inflammatory properties. This paper aims to investigate the impact of CQ on type 2 inflammatory response in MC903-induced AD mice. An AD mouse model was established via MC903 induction. After CQ treatment, AD mice were intraperitoneally injected with polyinosinic: polycyclic acid [poly (I:C)] or Nigericin. Dermatitis severity was scored, and the thickness of the left ear was measured. The pathological changes in mouse skin tissues were observed by H&E staining. The number of mast cells was counted via TB staining. The content of peripheral blood T-helper 2 (Th2) cells and levels of immunoglobulin E (IgE), thymic stromal-derived lymphopoietin (TSLP), interleukin (IL)-4, IL-13, interferon (IFN)-γ, IL-1β, and IL-18 were assessed by flow cytometry and ELISA. The levels of toll-like receptor 3 (TLR3), NLRP3, ASC, and cleaved caspase-1 proteins in skin tissues were determined by Western blot. CQ treatment abated dermatitis severity and left ear thickness in AD mice, alleviated skin damage, reduced mast cell number, diminished IgE, TSLP, IL-4, and IL-13 levels, and peripheral blood Th2 cell content, with no significant changes in IFN-γ level. CQ alleviated type 2 inflammatory response in AD mice by inhibiting the activation of TLR3. CQ suppressed NLRP3 inflammasome activation. Activating TLR3/NLRP3 annulled CQ-mediated alleviation on type 2 inflammatory response in AD mice. CQ alleviated type 2 inflammatory response in AD mice by inhibiting TLR3 activation and NLRP3 inflammasome activation.

Segmentation of hyphae and yeast in fungi-infected tissue slice images and its application in analyzing antifungal blue light therapy.

Candida albicans is a pathogenic fungus that undergoes morphological transitions between hyphal and yeast forms, adapting to diverse environmental stimuli and exhibiting distinct virulence. Existing research works on antifungal blue light (ABL) therapy have either focused solely on hyphae or neglected to differentiate between morphologies, obscuring potential differential effects. To address this gap, we established a novel dataset of 150 C. albicans-infected mouse skin tissue slice images with meticulously annotated hyphae and yeast. Eleven representative convolutional neural networks were trained and evaluated on this dataset using seven metrics to identify the optimal model for segmenting hyphae and yeast in original high pixel size images. Leveraging the segmentation results, we analyzed the differential impact of blue light on the invasion depth and density of both morphologies within the skin tissue. U-Net-BN outperformed other models in segmentation accuracy, achieving the best overall performance. While both hyphae and yeast exhibited significant reductions in invasion depth and density at the highest ABL dose (180J/cm2), only yeast was significantly inhibited at the lower dose (135J/cm2). This novel finding emphasizes the importance of developing more effective treatment strategies for both morphologies.

Necrosulfonamide promotes hair growth and ameliorates DHT-induced hair growth inhibition

BackgroundAlopecia affects patients' appearance and psychology. Mixed-lineage kinase domain-like pseudokinase (MLKL)-mediated necroptosis plays a role in various skin diseases, but its effect on hair growth is unclear. ObjectiveTo investigate the effects of MLKL on hair growth and its regulatory mechanisms and to determine the potential clinical value of Necrosulfonamide (NSA, a MLKL-targeting inhibitor) in promoting hair growth and counteracting dihydrotestosterone (DHT) inhibition of hair growth. MethodsThe expression level of MLKL was detected in the scalp of androgenetic alopecia (AGA) patients and the skin tissues of mice. Knock down MLKL expression or use NSA to observe hair growth in vivo and in vitro. ResultsIn AGA patients, MLKL expression is elevated in the alopecia areas. In mice, MLKL is significantly expressed in the outer root sheath (ORS) cells of hair follicles, peaking during the catagen phase. Knockdown expression of MLKL in mice skin promoted hair growth. NSA enhanced hair growth and prevented hair follicle regression via the Wnt signaling. Reduced MLKL boosts ORS cell proliferation without directly impacting DPCs' growth. Interestingly, NSA boosts DPCs' proliferation and induction when co-cultured with ORS cells. Besides, NSA alleviated the inhibition of DHT on hair growth in vivo and vitro. ConclusionNSA inhibited the activation of MLKL in ORS cells, promoted the activation of Wnt signal in DPC cells, and improved the inhibition of hair growth by DHT, illuminating a new alopecia mechanism and aiding anti-alopecia drug development.

Uncovering the impact of UV radiation on mitochondria in dermal cells: a STED nanoscopy study

Mitochondria are essential organelles in cellular energy metabolism and other cellular functions. Mitochondrial dysfunction is closely linked to cellular damage and can potentially contribute to the aging process. The purpose of this study was to investigate the subcellular structure of mitochondria and their activities in various cellular environments using super-resolution stimulated emission depletion (STED) nanoscopy. We examined the morphological dispersion of mitochondria below the diffraction limit in sub-cultured human primary skin fibroblasts and mouse skin tissues. Confocal microscopy provides only the overall morphology of the mitochondrial membrane and an indiscerptible location of nucleoids within the diffraction limit. Conversely, super-resolution STED nanoscopy allowed us to resolve the nanoscale distribution of translocase clusters on the mitochondrial outer membrane and accurately quantify the number of nucleoids per cell in each sample. Comparable results were obtained by analyzing the translocase distribution in the mouse tissues. Furthermore, we precisely and quantitatively analyzed biomolecular distribution in nucleoids, such as the mitochondrial transcription factor A (TFAM), using STED nanoscopy. Our findings highlight the efficacy of super-resolution fluorescence imaging in quantifying aging-related changes on the mitochondrial sub-structure in cells and tissues.

Pulsatilla saponin inhibits the proliferation of keratinocytes and ameliorates imiquimod-induced psoriasis through the NF-κB and STAT3 signaling pathways

Background and aimPulsatilla saponin (Ps) was isolated from Pulsatilla chinensis (Bunge) Regel, a traditional Chinese medicine, that has anti-proliferation, anti-inflammation, anti-tumor and immunomodulation activities. However, the anti-psoriasis activity of Ps and its underlying mechanisms have not been fully elucidated. This study aims to investigate the effect and potential mechanisms of Ps on psoriasis. Experimental procedurePs underwent quality control through HPLC and NMR analysis. Wound healing assay, MTT, clone assay, and EdU staining were used to detect HaCaT cells proliferation. Western blot and immunofluorescence were used to assess the expression of proteins. The th17 cells population was analyzed by flow cytometry. The levels of cytokines in the mice skin tissues were measured by RT-qPCR and ELISA. Results and conclusionIn vitro, Ps has an inhibition effect on the proliferation of M5-induced HaCaT cells. Ps inhibited proliferation by regulating NF-κB and JAK1/STAT3 pathways. Additionally, Ps decreased TNF-α, IL-1β, and IL-6 mRNA levels in M5-induced HaCaT cells. In vivo, Ps improved the pathological damage of Imiquimod (IMQ)-induced psoriasis BALB/c mice skin and reduced the Ki67 level in mice skin tissue. Further results showed that Ps decreased Th17 cells differentiation and IL-22, IL-17A, IL-6, IFN-γ, TNF-α, and IL-1β secretion. Ps could ameliorate the psoriatic symptoms, decrease M5-induced HaCaT cell proliferation, and decrease the differentiation of Th17 cells in IMQ-induced psoriasis mice. Ps suppressed the release of inflammation cytokines by regulating NF-κB and JAK1/STAT3 pathways. Those results indicate that Ps has promising therapeutic potential for psoriasis treatment.

MicroRNA-21a-5p inhibition alleviates systemic sclerosis by targeting STAT3 signaling

BackgroundMicroRNA (miRNA)-21-5p participates in various biological processes, including cancer and autoimmune diseases. However, its role in the development of fibrosis in the in vivo model of systemic sclerosis (SSc) has not been reported. This study investigated the effects of miRNA-21a-5p overexpression and inhibition on SSc fibrosis using a bleomycin-induced SSc mouse model.MethodsA murine SSc model was induced by subcutaneously injecting 100 μg bleomycin dissolved in 0.9% NaCl into C57BL/6 mice daily for 5 weeks. On days 14, 21, and 28 from the start of bleomycin injection, 100 μg pre-miRNA-21a-5p or anti-miRNA-21a-5p in 1 mL saline was hydrodynamically injected into the mice. Fibrosis analysis was conducted in lung and skin tissues of SSc mice using hematoxylin and eosin as well as Masson’s trichrome staining. Immunohistochemistry was used to examine the expression of inflammatory cytokines, phosphorylated signal transducer and activator of transcription-3 (STAT3) at Y705 or S727, and phosphatase and tensin homologue deleted on chromosome-10 (PTEN) in skin tissues of SSc mice.ResultsMiRNA-21a-5p overexpression promoted lung fibrosis in bleomycin-induced SSc mice, inducing infiltration of cells expressing TNF-α, IL-1β, IL-6, or IL-17, along with STAT3 phosphorylated cells in the lesional skin. Conversely, anti-miRNA-21a-5p injection improved fibrosis in the lung and skin tissues of SSc mice, reducing the infiltration of cells secreting inflammatory cytokines in the skin tissue. In particular, it decreased STAT3-phosphorylated cell infiltration at Y705 and increased the infiltration of PTEN-expressing cells in the skin tissue of SSc mice.ConclusionMiRNA-21a-5p promotes fibrosis in an in vivo murine SSc model, suggesting that its inhibition may be a therapeutic strategy for improving fibrosis in SSc.

Tat-CIRP Peptide Facilitates Frozen Wound Healing by Ameliorating Inflammation and Promoting Angiogenesis.

Frostbite is a chemia resulting from cold-induced skin damage. The process of frostbite is often accompanied by inflammation, and the therapeutic strategies focusing on anti-inflammation are the main direction to data. Tat-CIRP is a 15 amino acid peptide containing HIV protein and cold-inducible RNA-binding protein (CIRP), which is believed to compete with endogenous CIRP for myeloid differentiation 2 (MD2) binding. This study aims to investigate the efficacy of Tat-CIRP in the treatment of frostbite. A mouse model of frostbite was established, and on the first day after frostbite occurrence, Tat-CIRP peptide was administered intravenously via the tail with a dosage interval of one day for a total of three doses. Frozen mouse skin sections were subjected to histological analysis, including hematoxylin-eosin (HE) staining, Masson staining, and immunohistochemical examination. Western blotting was performed to detect the expression level of Ki-67 in mouse skin tissue. One day after frostbite, mice exhibited skin swelling and a solid appearance. From day 1 to 5 after frostbite, MD2 expression was significantly upregulated, while CIRP expression was downregulated. Compared to the frostbite group, mice treated with Tat-CIRP showed accelerated frostbite recovery, reduced levels of inflammatory factors and MD2. Furthermore, the expression of cell proliferation-associated protein Ki-67 and angiogenesis-related protein CD31 was upregulated. Tat-CIRP promotes frozen wound healing via inhibiting inflammation and promoting angiogenesis in frostbitten mice.

HSP47 Increases the Expression of Type I Collagen in Fibroblasts through IRE1α Activation, XBP1 Splicing, and Nuclear Translocation of β-Catenin.

Heat shock protein 47 (HSP47), also known as SERPINH1, functions as a collagen-specific molecular chaperone protein essential for the formation and stabilization of the collagen triple helix. Here, we delved into the regulatory pathways governed by HSP47, shedding light on collagen homeostasis. Our investigation revealed a significant reduction in HSP47 mRNA levels in the skin tissue of older mice as compared to their younger counterparts. The augmented expression of HSP47 employing lentivirus infection in fibroblasts resulted in an increased secretion of type I collagen. Intriguingly, the elevated expression of HSP47 in fibroblasts correlated with increased protein and mRNA levels of type I collagen. The exposure of fibroblasts to IRE1α RNase inhibitors resulted in the reduced manifestation of HSP47-induced type I collagen secretion and expression. Notably, HSP47-overexpressing fibroblasts exhibited increased XBP1 mRNA splicing. The overexpression of HSP47 or spliced XBP1 facilitated the nuclear translocation of β-catenin and transactivated a reporter harboring TCF binding sites on the promoter. Furthermore, the overexpression of HSP47 or spliced XBP1 or the augmentation of nuclear β-catenin through Wnt3a induced the expression of type I collagen. Our findings substantiate that HSP47 enhances type I collagen expression and secretion in fibroblasts by orchestrating a mechanism that involves an increase in nuclear β-catenin through IRE1α activation and XBP1 splicing. This study therefore presents potential avenues for an anti-skin-aging strategy targeting HSP47-mediated processes.

Long-term intake of sulforaphene alleviates D-galactose-induced skin senescence by activating AMPK-Sirt 1 pathway.

D-Galactose (D-gal) accumulation triggers the generation of oxygen free radicals, resulting in skin aging. Sulforaphene (SFE), an isothiocyanate compound derived from radish seeds, possesses diverse biological activities, including protective effects against inflammation and oxidative damage. This investigation delves into the antioxidant impact of SFE on age-related skin injury. In vivo experiments demonstrate that SFE treatment significantly improves the macro- and micro-morphology of dorsal skin. It effectively diminishes the elevation of oxidative stress biomarkers in mice skin tissue treated with D-gal, concurrently enhancing the activity of antioxidant enzymes. Additionally, SFE mitigates collagen mRNA degradation, lowers pro-inflammatory cytokine levels, and downregulates MAPK-related protein expression in the skin. Moreover, SFE supplementation reduces lipid metabolite levels and elevates amino acid metabolites, such as L-cysteine and L-histidine. These findings suggest that SFE holds promise as a natural remedy to mitigate aging induced by oxidative stress.

The Effect of Sapodilla Leaf Extract on IL-6 and TGF- β Levels of Skin Tissue (Experimental Study on Male White Rats of Wistar Strain Exposed to UV Light)

Excessive exposure to ultraviolet light affects cell and tissue homeostasis which has a damaging effect on DNA characterized by the formation of reactive oxygen species (ROS). Inflammation due to UV rays is the main cause of oxidative stress in the skin. Healing of wounds caused by sunburn through a complex process consisting of inflammatory cell infiltration, cell proliferation, and tissue remodeling phases to restore normal skin integrity and function, rapid healing and epithelialization to prevent infection and minimize functional and aesthetic complications. The researchers aimed to see the effect of administering sapodilla leaf extract cream (Manilkara zapota) on IL-6 and TGF-β levels in Wistar rats with sunburn. Experimental study with a post test only control group design using a total of 30 mice as experimental animals, divided randomly into 4 treatment groups consisting of a control group, a placebo group, a sapodilla leaf cream group with a dose of 25% and a 50% cream group. Mouse skin tissue exposed to UV was analyzed using the ELISA method to determine the levels of IL-6 and TGF-β. There was no significant difference in the average IL-6 levels between treatment groups with the one way anova difference test, a p value of 0.25 (p0.05), there was a significant difference in the average TGF-β levels for each group with a p value of 0.005 (P0.05), Manilkara zapota leaf extract cream had a significant effect on TGF-β levels at a dose of 50%. Administration of Manilkara zapota leaf extract cream has a dose-dependent effect on IL-6 and TGF-β levels in skin tissue of mice exposed to UV.

Effect of Petai Bark Extract Gel on Tyrosinase and TRP1 Gene Expression (In Vivo Experimental Study on Hyperpigmented Wistar Mice Exposed to UVB Model)

UVB irradiation can induce the formation of Reactive Oxygen Species (ROS) which causes activation of melanin synthesis through activation of tyrosinase and tyrosinase related protein-1 (TRP1). Secondary metabolites contained in petai peel extract are known to play a role in inhibiting ROS production due to exposure to UVB rays. This study aims to determine the effect of administering petai peel extract gel on the expression of the tyrosinase and TRp1 genes in mouse skin tissue exposed to UVB. The research design was posttest only control group with a completely randomized design method. The samples studied were 24 mice exposed to UVB light with a wavelength of 302 nm and an energy of 390mJ/cm2/day 3 times a week for 2 weeks. This research was carried out in four groups, namely the healthy group (K1), the negative control group (K2), treatment 1 (K3) with 10% petai peel extract gel and treatment 2 (K4) with 20% petai peel extract gel. Tyrosinase and TRP1 gene expression was analyzed using qRT-PCR. qRT-PCR analysis showed that there was a significant decrease in tyrosinase and TRP1 gene expression between groups K3 (tyrosinase 3,19±2,12 and TRP1 4,96±3,42) and K4 (tyrosinase 0,65±0,44 and TRP1 2,22±1,18) compared to group K2 (tyrosinase 17,92±3,77 and TRP1 35,91±4,52). Administration of petai peel extract gel can reduce the expression of tyrosinase and TRP1 genes in hyperpigmentation mice exposed to UVB light.

Study on the Efficacy and Potential Mechanism of Topical Shen Bai Hair Growing Decoction against Androgenetic Alopecia Based on Ultrahigh Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry and RNA-seq.

Androgenetic alopecia (AGA) is a major problem that can happen to people of all ages, leading to psychological problems, such as anxiety and depression. Topical Shen Bai hair growing decoction (TSBHGD) is based on the pathogenesis of AGA, combined with Traditional Chinese Medicine theory, improved by the Tianjin Academy of Traditional Chinese Medicine Affiliated Hospital according to its clinical treatment experience. This study was designed to demonstrate the therapeutic efficacy of TSBHGD against AGA, analyze the chemical components of TSBHGD as well as the skin-retained and blood-retained components in mice after topical administration of TSBHGD, and clarify the mechanism of its therapeutic efficacy. It was demonstrated that TSBHGD could suppress TNF-α and IL-6 levels and improve pathological phenomena such as hair loss, reduced follicle density, and dermal thickness caused by testosterone solution. Totally 35 components were identified in TSBHGD extracts, 12 skin-retained components were identified in drug-containing skin, and 7 blood-retained components were identified in drug-containing plasma, according to ultrahigh performance liquid chromatography quadrupole time-of-flight mass spectrometry. Transcriptomic sequencing revealed that some of the genes in AGA mice had altered expression patterns, which could be reversed by TSBHGD. Through network pharmacology analysis, it was found that TSBHGD mainly regulated eight signaling pathways, among which the apoptosis signaling pathway ranked first with a significance of 0.00149. Finally, both Bcl-2 and Caspase family proteins in the apoptosis signaling pathway were examined by Western blot. It was confirmed that TSBHGD could inhibit the apoptosis level in AGA mice's skin tissue to exert an anti-AGA effect. This will facilitate the development of new-generation herbal compound formulas with precise efficacy and provide novel ideas for AGA therapy.

Anticipation and Verification of Dendrobium-Derived Nanovesicles for Skin Wound Healing Targets, Predicated Upon Immune Infiltration and Senescence.

Dendrobium, with profound botanical importance, reveals a rich composition of bioactive compounds, including polysaccharides, flavonoids, alkaloids, and diverse amino acids, holding promise for skin regeneration. However, the precise mechanism remains elusive. Seeking a potent natural remedy for wound healing, exocyst vesicles were successfully isolated from Dendrobium. This investigation aimed to employ bioinformatics and in vivo experiments to elucidate target genes of Dendrobium-derived nanovesicles in skin wound healing, focusing on immune infiltration and senescence characteristics. C57 mice experienced facilitated wound healing through Dendrobium-derived nanovesicles (DDNVs). Bioinformatics analysis and GEO database mining identified crucial genes by intersecting immune-related, senescence-related, and PANoptosis-associated genes. The identified genes underwent in vivo validation. DDNVs remarkably accelerated skin wound healing in C57 mice. Bioinformatics analysis revealed abnormal expression patterns of immune-related, senescence-related, and pan-apoptosis-related genes, highlighting an overexpressed IL-1β and downregulated IL-18 in the model group, Exploration of signaling pathways included IL-17, NF-kappa B, NOD-like receptor, and Toll-like receptor pathways. In vivo experiments confirmed DDNVs' efficacy in suppressing IL-1β expression, enhancing wound healing. Plant-derived nanovesicles (PDNV) emerged as a natural, reliable, and productive approach to wound healing. DDNVs uptake by mouse skin tissues, labeled with a fluorescent dye, led to enhanced wound healing in C57 mice. Notably, IL-1β overexpression in immune cells and genes played a key role. DDNVs intervention effectively suppressed IL-1β expression, accelerating skin wound tissue repair.

Persicaria senticosa extract mitigates ultraviolet B-induced photoaging by suppressing the mitogen-activated protein kinase/activator protein 1/matrix metalloproteinase 1 pathway in human keratinocytes and hairless mice

Ultraviolet (UV) irradiation has been identified as a key trigger for skin photoaging, characterized by the overproduction of matrix metalloproteinases (MMPs) and reactive oxygen species (ROS), along with the accelerated decomposition of extracellular matrix (ECM) proteins, ultimately contributing to the development of wrinkles. Persicaria senticosa (PS) extracts are recognized for their antioxidative properties and their importance in skin health. Nevertheless, there is a paucity of studies investigating the potential of PS in protecting the skin against photoaging. The present study aimed to assess the effectiveness of PS extracts in preventing photoaging and elucidating the molecular mechanisms involved in using immortalized human keratinocytes (HaCaT) and hairless mice. The major bioactive constituents of PS were identified as p-coumaric acid, isoquercitrin, quercetin-3-O-glucuronide, and quercetin. Aqueous extracts of PS exhibited the ability to mitigate UVB-induced cellular damage and diminished ROS generation in HaCaT cells. Moreover, treatment with PS effectively attenuated the upregulated expression of matrix metalloproteinase-1 (MMP-1) and collagen degradation induced by UVB exposure. The property of PS to counteract photoaging was related to its capacity to inhibit the UVB-induced phosphorylation of mitogen-activated protein kinase (MAPK) and suppress the subsequent activation of activator protein 1 (AP-1) signaling pathways. Moreover, in hairless mice exposed to UVB radiation, the application of PS significantly alleviated the development of skin wrinkles, diminished epidermal thickening, and mitigated collagen degradation. Notably, PS treatment resulted in the downregulation of the UVB-activated MAPK/AP-1/MMP-1 pathway in mouse skin tissues. These findings suggest that PS has the potential to serve as a therapeutic agent for treating photoaging, holding promises in both cosmeceutical and pharmaceutical applications.

Exploring the impedance-matching effect in terahertz reflection imaging of skin tissue.

Terahertz (THz) electromagnetic waves, known for their unique response to water, offer promising opportunities for next-generation biomedical diagnostics and novel cancer therapy technologies. This study investigated the impedance-matching effect, which enhances the efficiency of THz wave delivery into tissues and compensates for the signal distortion induced by the refractive index mismatch between the target and the sample substrate. Three candidate biocompatible materials, water, glycerol, and petroleum jelly were applied to a skin phantom and compared using THz two-dimensional imaging and time-of-flight imaging methods. Finally, we successfully demonstrated impedance-matching effect on mouse skin tissues.

Minoxidil delivered via a stem cell membrane delivery controlled release system promotes hair growth in C57BL/6J mice.

Objective: Umbilical cord-derived mesenchymal stem cell membrane-loaded minoxidil (MXD) nanoparticles (STCM-MXD-NPs) were prepared to investigate their effects on hair growth in C57BL/6J mice. Methods: STCM-MXD-NPs were obtained by freeze-thawing and differential centrifugation, and their effects on hair growth were evaluated using C57BL/6J mice. The mRNA and protein expression levels of vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF-1) were detected by real-time polymerase chain reaction and enzyme-linked immunosorbent assays, respectively. Protein expression levels of marker of proliferation Ki-67 (MKI67) and β-catenin (CTNNB) in skin tissue were detected by immunohistochemistry. Results: STCM-MXD-NPs improved MXD solubility. They released the drug slowly, increasing its transdermal properties, accumulation in the skin, and content in the hair bulb tissues with a better efficacy than that of ordinary MXD. Moreover, STCM-MXD-NPs significantly upregulated the mRNA and protein levels of VEGF and IGF-1 and promoted the protein expression of MKI67 and CTNNB in mouse skin tissues, promoting mouse hair growth. Conclusion: Stem cell membrane-loaded MXD nanoparticles with slow-release properties increased MXD accumulation in the skin by improving its transdermal properties, increasing VEGF, IGF-1, MKI67, and CTNNB expression levels and promoting hair growth in C57BL/6J mice.

(-)-α-Bisabolol inhibits D-Gal-induced HSF cellular senescence in vitro and prevents skin aging in vivo by reducing SASP.

To study the anti-aging effect of (-)-α-bisabolol ((-)-α-bis) on the skin and preliminarily clarify its mechanism. Human skin fibroblasts (HSF) were induced senescence by D-Galactose. Senescence β-galactosidase staining was utilized to evaluate the senescence of HSF. TNF-α, IL-6, IL-8, IL-1β, CCL-2, CCL-5, and MMP-9 in senescence-as-sociated secretory phenotype (SASP) were detected by RT-qPCR. Meanwhile, aged BALB/c mice were applied topically with 0.5% and 2%(-)-α-bis gel for 30 days continuously to evaluate anti-aging parameters on the skin such as surface measurement, the Trans Epidermal Water Loss (TEWL), and skin barrier index of dorsal skin. Then, HE staining, Masson staining, and IHC were applied to measure epidermal thickness, collagen fiber content in the dermis, and content of dermal collagen I, respectively. Last, SOD, MDA, and HYP contents of the back skin tissue of mice were also detected. (-)-α-Bis reduced the expression of senescence-associated β-galactosidase (SA-β-gal) and expression levels of SASP in HSF cells stimulated by D-Gal (P<0.05). Mice aged 9 months were applied locally with (-)-α-bis gel to improve skin aging, the TEWL and skin barrier index of dorsal skin, and ameliorate the epidermal thickness and contents of dermal collagen fibers and collagen I (P<0.05). Furthermore, (-)-α-bis up-regulated the mRNA expression levels of elastin and collagen III effectively (P<0.05). (-)-α-Bis can delay the senescence of HSF cells by reducing the expression of SA-β-gal and SASP factors in vitro. Improved skin barrier function as well as SASP is responsible for the delay of skin aging in vivo.

Oral Administration of Lactilactobacillus curvatus LB-P9 Promotes Hair Regeneration in Mice.

This study was designed to examine the effect of Lactilactobacillus curvatus LB-P9 on hair regeneration. The treatment of LB-P9 conditioned medium increased the proliferation of both hair follicle dermal papilla cells and hair germinal matrix cells (hGMCs). Moreover, the expression levels of hair growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor 7 were significantly elevated in hGMCs co-cultured with LB-P9. After time-synchronized depilation, mice were orally administered with either 4×107 colony forming unit (CFU) of LB-P9 (low dose) or 4×108 CFU of LB-P9 (high dose), once daily for 4 weeks. Compared with the vehicle (phosphate-buffered saline)-administrated group, the LB-P9-treated groups exhibited accelerated hair regrowth rate and enhanced hair thickness in a dose-dependent manner. Supporting this observation, both hair follicle numbers and the dermal thickness in skin tissues of the LB-P9-treated groups were increased, compared to those of the vehicle-treated group. These results might be explained by the increased level of β-catenin and number of hair follicle stem cells (CD34+CD49f+ cells) in the skin tissues of mice administered with LB-P9, compared to the vehicle-treated mice. Also, increased serum levels of hair growth factors such as VEGF and insulin-like growth factor-1, and superoxide dismutase were found in the LB-P9-treated groups, compared to those of the vehicle-treated group. Taken together, these results might demonstrate that the oral administration of LB-P9 promotes hair regeneration by the enhancement of dermal papilla proliferation through the stimulation of hair growth factor production.