Untreated Skin Research Articles

Retention of nickel, cobalt and chromium in skin at conditions mimicking intense hand hygiene practices using water, soap, and hand-disinfectant in vitro

BackgroundDuring the COVID-19 pandemic, increased hand hygiene practices using water, soap and hand disinfectants, became prevalent, particularly among frontline workers. This study investigates the impact of these practices on the skin’s ability to retain the allergenic metals nickel, cobalt, and chromium. The study constitutes three parts: (I) creating an impaired skin barrier, (II) exposing treated and untreated skin to nickel alone, and (III) in co-exposure with cobalt and chromium.MethodsUsing full-thickness skin from stillborn piglets, in vitro experiments were conducted to assess retention of metals in skin at conditions mimicking intense hand hygiene practices. Treatment of skin with varying concentrations of sodium lauryl sulphate (SLS), to impair its barrier integrity was assessed. This was followed by exposure of treated and untreated skin to the metals, that were dissolved in Milli-Q water, 0.5% SLS, and ethanol respectively.ResultsResults showed that pre-treatment with 5% SLS impaired the skin barrier with regards to the measure of trans epidermal water loss (TEWL). Metal amounts retained in the skin were generally higher in treated than untreated skin. The highest amounts of metal retained in skin were observed for exposure to nickel in ethanol. Co-exposure to nickel, cobalt, and chromium in 0.5% SLS resulted in the highest amounts of total metal retention.ConclusionsThe in vitro findings highlight the increased risk of metal retention in skin due to an impaired barrier. The SLS concentration used in the current study corresponds to those used in many hand hygiene products. Hence, occupational settings with frequent exposure to water, soap and disinfectants need to consider protective measures not only for the irritant exposures themselves but also simultaneous exposure to allergenic metals.

Epicutaneous house dust mite (HDM)-induced skin lesions feature early activation of T helper 2 inflammatory and pruritogenic pathways in HDM-nonsensitised dogs.

Epicutaneously house dust mite-sensitised (HDM-S) healthy dogs are commonly used as canine atopic dermatitis (cAD) models; however, the exact mechanisms of HDM-induced AD immune activation in HDM-S and HDM-nonsensitised (NS) dogs remain unclear. To characterise the inflammatory and pruritogenic transcriptome of acute epicutaneous HDM-induced skin lesions at 6 h and 24 h in HDM-NS and HDM-S dogs; untreated skin at 0 h from each dog served as control. Six HDM-S and six HDM-NS laboratory beagles. Processed expression data from GEO deposited by Schamber etal. (G3 (Bethesda), 2014, 4 and 1787) (GSE58442) were downloaded and analysed using R and the Bioconductor package. Significance analysis was performed with the limma package; genes with false discovery rate <0.05 and fold-change ≤/≥1.5 were considered significantly differentially expressed (DEGs). A 2D principal component analysis revealed no clear separation between HDM-NS and HDM-S dogs at 6 h and 24 h time points. HDM-induced skin lesions in sensitised and nonsensitised dogs at the 24 h time point showed significant upregulation of T helper cell (Th)2 genes (interleukin [IL]-4R, IL-5, IL-13, CCL13 and CCL17), as well as proinflammatory- (LTB, IL-1A and IL-18), Th1- (CXCL10, OASL and MX-1) and Th17-related markers (IL-17B, IL-17F, CCL19 and CCL20). The key Th22-related maker, IL-22, was upregulated only in the HDM-S group at the 24 h time point. Both groups at 24 h featured significant upregulation of several noncytokine pruritogens, such as trypsin, chymase, cathepsin S, periostin and neuromedin B. Taken together, we establish that epicutaneous HDM patch application induces immune changes in HDM-NS dogs with Th2 dominance and activates several itch-promoting pathways.

Microneedle created in skin in situ forming gels depot; an alternate approach to the sustained transdermal delivery of colchicine

Colchicine (CLC) is a commonly used medication in prevention and treatment of acute gout condition via oral route. However its oral administrations pose several gastrointestinal (GI) adverse effects. In current study, an alternate combinatorial approach of microneedles patch and in skin forming gel depots were evaluated for sustained CLC delivery through skin using CLC loaded non-ionic amphiphilic triblock pluronic-127 thermoresponsive poloxamers. In first phase, to validate the development of in situ forming depots, the phase transition of pluronic-127 from the sol-gel state was examined using AR2000 rheometer. In second phase, microneedles patches (MAPs) were fabricated via casting method utilizing (19 × 19) laser-engineered silicone micromoulds from varied biocompatible polymer blends such as Gantrez S-97, Poly-vinyl alcohol, Polyethelene glycol 10000 and Poly (vinylpyrollidone) at various concentrations. For optimized MAPs, the mechanical strength, in skin dissolution kinetics and moisture contents were determined. From mechanical testing PVP and PVA MAPs showed more brittle nature and highest loss of MAPs reduction in comparison to Gantrez® MAPs. Optimized MAPs (Gantrez®) based on high mechanical strength were utilized as a microporation source in rabbit skin. In comparison to PVA and PVP, Gantrez® MAPs showed slow dissolution kinetics and resist dissolution for 540 s. Optical coherence tomography (OCT) quantified the penetration depth of Gantrez® MAPs in newborn rabbit skin at 591 μm. Increased in TEWL values after Gantrez® MAPs treatment confirmed the pores formation in skin. Ex-vivo permeation analysis showed that 25 % w/w CLC loaded PF127® gel showed controlled and prolonged drug permeation across microporated skin for 84 h in comparison to untreated skin. The distribution of PF127 gel solution in treated skin samples was confirmed by tracking fluorescence using confocal microscopy. Results shows that MAPs created in skin micropores can be used as CLC depots and sustained effects can be achieved by successfully avoiding oral route and GI adverse effects.

Physicochemical Characteristics and Stability Assessment of A Topical Formulation Comprising Allium cepa and Quercetin for Cutaneous Scar Management

The 12% Allium cepa extract topical formulation, with proven clinical benefits, targets improved surgical scar appearance. This study aims to comprehensively assess the physicochemical characteristics and stability of a scar-reducing formulation (15% Allium cepa-micellar extract, 0.01% quercetin). In vitro-release and skin permeation studies were conducted, alongside FTIR and DSC analyses to elucidate the skin permeation mechanism. Quercetin remaining at 25 and 40 °C ranged from 99 to 100% (day 60) and 101 to 104% (day 90), while antioxidant activity (53-65%, day 90) remained comparable to the standard quercetin (84.70% at 40 μg/mL). In the context of in vitro quercetin release, the performances were ranked as shallot-micellar extract &gt; scar-reducing formulation plus shallot-micellar extract &gt; scar-reducing formulation, with no significant differences observed (P &lt; 0.05). Importantly, scar-reducing formulation plus shallot-micellar extract and shallot-micellar extract showed a significant difference (P &lt; 0.05) compared to shallot-water extract and the commercial product. The treated skin showed minor changes in the microstructure compared to untreated skin, indicating a gentle formulation, as observed in the FT-IR spectra and DSC thermograms. The findings from skin permeation mechanism studies imply that the scar-reducing formulation may deposit on the skin surface with minor alterations to the skin microstructure. A crucial consideration for future investigations is a long-term stability assessment of at least 12 months at 30°C, following ASEAN guidelines. The scar-reducing formulation was stable at 25°C, without exceeding 40°C for 90 days. Storage at 4°C is not recommended due to the potential risk of decreased solubility and quercetin precipitation.

Effect of extracorporeal shock wave therapy on the microbial community in burn scars: retrospective case-control study.

The effectiveness of extracorporeal shock wave therapy (ESWT) has been demonstrated in various medical fields, including burn medicine. It promotes wound healing, improves blood flow, and modulates the inflammatory responses. The recovery speed and outcomes of skin diseases are influenced by the skin microbiome; however, studies examining the effects of specific treatments on the skin microbiome are lacking. This study investigated the impact of ESWT on the skin microbiome of burn patients, focusing on the microbial diversity and community structure within burn scars. In the retrospective case-control study, nineteen patients with burn scars were treated with ESWT, and changes in their skin microbiome were evaluated. ESWT was administered weekly for three months, and samples were collected from the ESWT-treated burn scars and untreated normal skin. Blood chemistry, and pain and itching scores were evaluated during sample collection. The collected samples were then subjected to 16S rRNA sequencing. Microbial community analysis was conducted using the QIIME2 and R packages. After ESWT, changes in alpha diversity indices were observed in burn scars. Faith phylogenetic diversity (P<0.05) and observed features (P<0.01) increased, whereas the evenness index decreased (P<0.01); no marked changes were noted in untreated skin. Beta diversity analysis showed stable microbial community structures in both the treated and untreated areas. A considerable increase in Micrococcus and Staphylococcus abundance was observed. Network analysis revealed a more open microbial network structure after ESWT, indicating adaptive changes in the microbial community. ESWT enhances microbial diversity and modifies microbial community structure in burn scars, promoting a more balanced and functionally supportive microbiome. ESWT aids in scar remodeling and positively influences skin microbiome dynamics, contributing to improved skin health and recovery.

Chitinase 3-Like 1 and C-X-C motif chemokine ligand 5 proteins and the hair cycle.

Dermal papilla cells (DPCs) exhibit self-recovery ability, which may be involved in hair growth. Therefore, we tested whether DPCs subjected to temporary growth-inhibiting stress (testosterone, 17β-estradiol, mitomycin C, or undernutrition) treatments exhibit self-recovery behavior that can activate hair follicle growth, and examined the changes in cell proliferation capacity and gene expression. Related proteins were identified and their relationships with the hair cycle was examined using a mouse model. Recovery-period DPCs (i.e., from day 3 after loading) were subjected to microarray analysis to detect genetic variations common to each stress treatment. Co-culture of recovery-period DPCs and outer root sheath cells (ORSCs) confirmed the promotion of ORSC proliferation, suggesting that the activation of hair follicle growth is promoted via signal transduction. Chitinase 3-like 1 (CHI3L1) and C-X-C motif chemokine 5 (CXCL5) exhibited ORSC proliferation-promoting effects. Measurement of protein content in the skin during each phase of the hair cycle in mice revealed that CHI3L1 and CXCL5 secretion increased immediately after anagen transition. In a hair-loss mouse model treated with testosterone or 17β-estradiol, CHI3L1 and CXCL5 secretion was lower in treated telogen skin than in untreated skin. Our results suggest that CHI3L1 and CXCL5 secreted by recovery-state DPCs promote hair growth.

Stability, Irritation Property and Anti-aging Clinical Evaluation of Hydroethanolic Dimocarpus longan Leaf Extract-Loaded Niosomes

This study aimed to develop hydroethanolic Dimocarpus longan leaf extract (HDLE)-loaded niosomes for enhancing polyphenols’ stability and efficiency for cosmeceutical applications. Moreover, its irritation property was clinically evaluated. HDLE was loaded into niosomes of cholesterol, sorbitan laurate, and polysorbate 20 at a 1:1:1.5 molar ratio. The suitable extract-loaded capacity was 0.5% (w/w), which provided the percentage of entrapment efficiencies of gallic acid, ethyl gallate and ellagic acid at 37.77 ± 0.93, 49.76 ± 0.20, and 62.85 ± 1.55, respectively. The HDLE-loaded niosomes showed a unilamellar structure under a transmission electron microscope. The particle size range was 255.45-356.15 nm with a low polydispersity index at initial and after storage for three months. The remaining percentage of gallic acid, ethyl gallate and ellagic acid in HDLE-loaded niosomes at all storage temperatures after three months was significantly higher than in the solution. HDLE-loaded niosomes presented no irritation effect on the chorioallantoic membranes (CAMs). The serum containing HDLE-loaded niosomes showed no irritation by the 4-hr human patch test. After applying twice daily for 60 days of water-based serum containing the HDLE-loaded niosomes compared with a placebo and untreated skin on different areas of forearms, the result demonstrated that HDLE-loaded niosomes serum was significantly effective in skin moisturization, elasticity induction and wrinkle reduction. In conclusion, due to their efficacy and safety, HDLE-loaded niosomes can be used for cosmetic applications.

Ferroptosis Inhibition with Deferoxamine Alleviates Radiation-Induced Fibrosis.

Background Radiation-induced fibrosis (RIF) is a debilitating sequelae of radiation therapy that has been shown to improve with topical treatment with the iron chelator deferoxamine (DFO). We investigated whether DFO exerts this effect through attenuation of ferroptosis, a recently described iron-dependent pathway of cell death. Methods Adult C57BL/6J mice were treated with topical DFO or ferrostastin-1 (Fer-1) and irradiated with 30 Grays of ionizing radiation to the dorsal skin to promote development of chronic RIF. Immunofluorescent staining with 4-hydroxynonenal (4-HNE) antibody was carried out directly following irradiation to assess ferroptosis activity. Perfusion testing with laser Doppler was performed throughout the healing interval. Eight weeks following radiation, dorsal skin was harvested and analyzed histologically and biomechanically. Results Immunohistochemical staining demonstrated lower presence of 4-HNE in non-irradiated skin, DFO-treated skin, and Fer-1-treated skin compared to irradiated, untreated skin. DFO resulted in histological measurements (dermal thickness and collagen content) that resembled normal skin, while Fer-1 treatment yielded less significant improvements. These results were mirrored by analysis of extracellular matrix ultrastructure and biomechanical testing, which recapitulated the ability of topical DFO treatment to alleviate RIF across these parameters while Fer-1 resulted in less notable improvement. Finally, perfusion levels in DFO treated irradiated skin were similar to measurements in normal skin, while Fer-1 treatment did not impact this feature. Conclusions Ferroptosis contributes to the development of RIF and attenuation of this process leads to reduced skin injury. DFO further improves RIF through additional enhancement of perfusion not seen with Fer-1.

Nano-Pulse Stimulation Therapy Initiates Regulated Cell Death in Skin, Unlike Bovie Radiofrequency Ablation and Cryoablation.

This study describes a unique new bioelectric approach for clearing skin lesions and illustrates the clinical and histological differences between this new method and the standards of cryoablation and Bovie® radiofrequency ablation (RFA). To determine the advantage of stimulating regulated cell death with nanosecond pulsed electric fields over the necrosis response elicited by thermal ablation modalities. Human abdominal skin was treated with cryoablation, Bovie® RFA, and nano-pulse stimulation (NPS) therapy four times before an abdominoplasty procedure was performed to collect skin for histology. The clinical appearance and corresponding histology of each treatment were documented over time and compared. NPS therapy triggered regulated cell death as indicated by the appearance of activated Caspase-3 at 2 h post treatment and the absence of nuclear staining 1 day post treatment. Epidermal regeneration follows without impacting the noncellular dermis in contrast to cryoablation and Bovie® RFA which trigger necrosis and often cause scarring, inflammation, or permanent pigmentary changes. The main differences between NPS therapy and other ablation modalities are the level of fibrosis, amount of scarring, elastic fiber concentration, and inflammation. An analysis of the skin thickness 30 days after the treatment indicates that NPS-treated skin is the most similar to untreated skin but cryoablated and RF-ablated skin were 2- and 3.5-fold thicker, respectively, suggesting that they initiate necrosis rather than regulated cell death. We conclude that NPS therapy is a unique nonthermal modality that may be applied for clearing benign skin lesions by initiating the skin's own programmed cell death pathway instead of necrosis as used by cryoablation and Bovie® RFA.

Dupilumab-associated head and neck dermatitis shows a pronounced type 22 immune signature mediated by oligoclonally expanded T cells

Dupilumab, an IL4R-blocking antibody, has shown clinical efficacy for atopic dermatitis (AD) treatment. In addition to conjunctivitis/blepharitis, the de novo appearance of head/neck dermatitis is now recognized as a distinct side effect, occurring in up to 10% of patients. Histopathological features distinct from AD suggest a drug effect, but exact underlying mechanisms remain unknown. We profiled punch biopsies from dupilumab-associated head and neck dermatitis (DAHND) by using single-cell RNA sequencing and compared data with untreated AD and healthy control skin. We show that dupilumab treatment was accompanied by normalization of IL-4/IL-13 downstream activity markers such as CCL13, CCL17, CCL18 and CCL26. By contrast, we found strong increases in type 22-associated markers (IL22, AHR) especially in oligoclonally expanded T cells, accompanied by enhanced keratinocyte activation and IL-22 receptor upregulation. Taken together, we demonstrate that dupilumab effectively dampens conventional type 2 inflammation in DAHND lesions, with concomitant hyperactivation of IL22-associated responses.

Deferoxamine topical cream superior to patch in rescuing radiation-induced fibrosis of unwounded and wounded skin.

Topical patch delivery of deferoxamine (DFO) has been studied as a treatment for this fibrotic transformation in irradiated tissue. Efficacy of a novel cream formulation of DFO was studied as a RIF therapeutic in unwounded and excisionally wounded irradiated skin. C57BL/6J mice underwent 30 Gy of radiation to the dorsum followed by 4 weeks of recovery. In a first experiment, mice were separated into six conditions: DFO 50 mg cream (D50), DFO 100 mg cream (D100), soluble DFO injections (DI), DFO 1 mg patch (DP), control cream (Vehicle), and irradiated untreated skin (IR). In a second experiment, excisional wounds were created on the irradiated dorsum of mice and then divided into four treatment groups: DFO 100 mg Cream (W-D100), DFO 1 mg patch (W-DP), control cream (W-Vehicle), and irradiated untreated wounds (W-IR). Laser Doppler perfusion scans, biomechanical testing, and histological analysis were performed. In irradiated skin, D100 improved perfusion compared to D50 or DP. Both D100 and DP enhanced dermal characteristics, including thickness, collagen density and 8-isoprostane staining compared to untreated irradiated skin. D100 outperformed DP in CD31 staining, indicating higher vascular density. Extracellular matrix features of D100 and DP resembled normal skin more closely than DI or control. In radiated excisional wounds, D100 facilitated faster wound healing and increased perfusion compared to DP. The 100 mg DFO cream formulation rescued RIF of unwounded irradiated skin and improved excisional wound healing in murine skin relative to patch delivery of DFO.

Topical Peroxisome Proliferator-Activated Receptor Agonist Induces Molecular Alterations Enhancing Barrier Function and Water-Holding Capacity of the Human Stratum Corneum In Vivo

The peroxisome proliferator-activated receptor (PPAR) ligands modulate a variety of skin functions but are rarely used in cosmetics. The aim of this double-blind, placebo-controlled, in vivo study was to determine the effect of a topically applied 0.1% PPAR ligand on the composition and physiological parameters of the stratum corneum (SC). By comparing verum and placebo groups post-treatment, we demonstrate (via lipidomic analysis of tape strips) an unstatistically significant trend toward an increase in long-chain triacylglycerols (C50–C56) and medium- and long-chain ceramides (C42–C50) at the superficial SC. By comparing treated and untreated skin using confocal Raman microspectroscopy, we found that the changes in lipid composition in the verum group led to a significant increase in the number of trans conformers and orthorhombic organisation of lipids at the exemplary SC depth. An increase in unfolded states in the secondary and tertiary keratin structures results in an increased ability to bind water. The concentrations of tightly and strongly bound water increase, while weakly bound and unbound water decrease in the entire SC, indicating a transformation of water mobility to a state of increased hydrogen bonding. Thus, the topical PPAR ligands improve the water-holding capacity and the barrier function of the SC.

Assessing the Effect of Enzymatic Debridement on the Scar Quality in Partial-Thickness Burns to Deep Dermal Burns of the Hand: A Long-Term Evaluation.

Background and Objectives: Burn surgery on the hands is a difficult procedure due to the complex anatomy and fragility of the area. Enzymatic debridement has been shown to effectively remove burn eschar while minimizing damage to the surrounding tissue and has therefore become a standard procedure in many burn centers worldwide over the past decade. However, surprisingly, our recent literature review showed limited valid data on the long-term scarring after the enzymatic debridement of the hands. Therefore, we decided to present our study on this topic to fill this gap. Materials and Methods: This study analyzed partial-thickness to deep dermal burns on the hands that had undergone enzymatic debridement at least 12 months prior. Objective measures, like flexibility, trans-epidermal water loss, erythema, pigmentation, and microcirculation, were recorded and compared intraindividually to the uninjured skin in the same area of the other hand to assess the regenerative potential of the skin after EDNX. The subjective scar quality was evaluated using the patient and observer scar assessment scale (POSAS), the Vancouver Scar Scale (VSS), and the "Disabilities of the Arm, Shoulder, and Hand" (DASH) questionnaire and compared interindividually to a control group of 15 patients who had received traditional surgical debridement for hand burns of the same depth. Results: Between January 2014 and December 2015, 31 hand burns in 28 male and 3 female patients were treated with enzymatic debridement. After 12 months, the treated wounds showed no significant differences compared to the untreated skin in terms of flexibility, trans-epidermal water loss, pigmentation, and skin surface. However, the treated wounds still exhibited significantly increased blood circulation and erythema compared to the untreated areas. In comparison to the control group who received traditional surgical debridement, scarring was rated as significantly superior. Conclusions: In summary, it can be concluded that the objective skin quality following enzymatic debridement is comparable to that of healthy skin after 12 months and subjectively fares better than that after tangential excision. This confirms the superiority of enzymatic debridement in the treatment of deep dermal burns of the hand and solidifies its position as the gold standard.

Stratum Corneum Lipids in Non-Lesional Atopic and Healthy Skin following Moisturizer Application: A Randomized Clinical Experiment.

It is an international standard to recommend patients with atopic dermatitis (AD) to use moisturizers; however, little is known about their effect on lipids in the stratum corneum (SC). In this randomized clinical experiment of 30 Caucasian participants (15 with AD and 15 healthy controls), the superficial SC lipid profile was assessed through tape stripping non-lesional skin following treatment thrice daily for seven days with a moisturizer, and subsequently compared with untreated skin. No discernible disparity in superficial SC lipid quantity was evident between the AD group and the control group. However, the SC lipid composition diverged significantly, with the AD group exhibiting diminished levels of long-chain EO CERs (p = 0.024) and elevated levels of short-chain C34 CERs (p = 0.025) compared to healthy skin. Moisturizer application significantly reduced the total SC lipids and all lipid subgroups in both groups. Within the AD group, a non-significant inclination towards an augmentation in EO CERs (p = 0.053) and reduction in C34 CERs (p = 0.073) was observed. The recent identification of distinctions in SC lipid composition between AD and healthy skin was substantiated by our findings. Topical moisturizer application, despite reducing overall total lipids, indicated a potential tendency towards a healthier lipid constitution in AD skin.

Ablative fractional CO2 laser treatment promotes wound healing phenotype in skin macrophages.

Ablative fractional laser (AFL) treatment is a well-established method for reducing signs of skin photoaging. However, the biological mechanisms underlying AFL-induced healing responses and skin rejuvenation remain largely unknown. It is known that macrophages play an important role in orchestrating healing, normalization, and remodeling processes in skin. Macrophage phenotypes are characterized by inflammatory markers, including arginase-1 (Arg1), major histocompatibility class II molecules (MHC II), and CD206. This study aims to explore AFL's effect on macrophage phenotype by evaluating changes in inflammatory markers and the potential concurrent accumulation of Arg1 in the skin. Mice (n = 9) received a single AFL treatment on the left side of the back skin (100 mJ/microbeam, 5% density) while the right side of the back remained untreated as control. Treated and untreated skin from each mouse were collected Day 5 posttreatment for flow cytometry and histology analysis. Flow cytometry evaluated the immune infiltration of macrophages and the expression of macrophage inflammatory markers (Arg1, MHC II, and CD206). In addition, Arg1 presence in the skin was evaluated through antibody staining of histology samples and quantification was performed using QuPath image analysis software. Following AFL, the number of macrophages increased 11-fold (p = 0.0053). Phenotype analysis of AFL-treated skin revealed an increase in the percentage of macrophages positive for Arg1 (p < 0.0001) and a decrease in the percentage of macrophages positive for MHC II (p < 0.0001) compared to untreated skin. No significant differences were observed in percentage of CD206-positive macrophages (p = 0.8952). Visualization of AFL-treated skin demonstrated a distinct pattern of Arg1 accumulation that correlated with the microscopic treatment zones (MTZ). Quantification of the percentage of Arg1-positive area in epidermis and dermis showed a significant increase from 3.5% ± 1.2% to 5.2% ± 1.7 (p = 0.0232) and an increase from 2.2% ± 1.2% to 9.6% ± 3.3 (p < 0.0001) in whole skin samples. AFL treatment polarizes macrophages toward a wound healing phenotype and induces Arg1 accumulation in the MTZ. We propose that the polarized wound healing macrophages are a major source for the increased Arg1 levels observed in the skin following treatment.

Topical application of jojoba (Simmondsia chinensis L.) wax enhances the synthesis of pro-collagen III and hyaluronic acid and reduces inflammation in the ex-vivo human skin organ culture model.

Jojoba (Simmondsia chinensis L.) wax was previously reported to increase cutaneous wound healing, ameliorate acne and psoriasis manifestations, and reduce oxidative stress and inflammation. However, its potential cosmetic properties have not been fully investigated. Thus, the current study aimed to evaluate the anti-inflammatory activities of jojoba wax and its impact on the synthesis of extracellular components following topical application. The fatty acid and fatty alcohol profiles of two industrial and two lab-scale cold-press jojoba waxes were analyzed along with total tocopherol and phytosterol content. The dermo-cosmetic effect of all jojoba wax preparations was evaluated ex-vivo, using the human skin organ culture model, which emulates key features of intact tissue. The ability of jojoba wax to reduce secreted levels of key pro-inflammatory cytokines and the safety of the applications in the ex-vivo model were evaluated. In addition, the impact on the synthesis of pro-collagen and hyaluronic acid levels upon treatment was investigated. The results demonstrate that topically applied jojoba wax can reduce LPS-induced secretion of IL-6, IL-8, and TNFα by approx. 30% compared to untreated skin. This effect was enhanced when treatment was combined with low non-toxic levels of Triton X-100, and its efficacy was similar to the anti-inflammatory activity of dexamethasone used as a positive control. In addition, mRNA and protein levels of collagen III and synthesis of hyaluronic acid were markedly increased upon topical application of jojoba. Moreover, the enhanced content of extracellular matrix (ECM) components correlated with the enhanced expression of TGFβ1. Collectively, our results further demonstrate that jojoba can reduce local skin inflammation, and this effect may be increased by emulsifier which increases its bioavailability. In addition, the finding that topical application of jojoba wax enhances the synthesis of pro-collagen and hyaluronic acid and may be beneficial in the treatment of age-related manifestations.

Coenzyme Q10-loaded nanoemulsion hydrophilic gel: Development, characterization, stability evaluation and in vivo effects in skin

This study aimed to develop a physically and chemically stable hydrogel, which contains coenzyme Q10 (Q10)-loaded nanoemulsion, able to reduce transepidermal water loss (TEWL) and enhance skin hydration. Q10-loaded nanoemulsion was, after its characterization (particle size, polydispersity index (PDI), oxidation index, pH value, Q10-content, and electron microscopy) incorporated into a carbomer gel. The prepared Q10-loaded nanoemulsion gel was analyzed for its rheological parameters, pH value and Q10-content, after its preparation (48 h), after the stress test (5 cycles; 1 cycle: 24 h at 4 °C, 24 h at 20±2 °C and 24 h at 40 °C) and at predetermined time intervals during its storage at 20±2 °C and at 40 °C for six months. The Q10-loaded nanoemulsion gel, plain Q10-gel, Q10-free nanoemulsion gel and placebo carbomer gel were investigated in vivo for their effects in 15 human volunteers, during their 28 days’ application onto the skin. Skin hydration and TEWL were determined before starting the treatment, during 28 days of treatment, and 4 days after treatment completion. The results showed that the Q10-nanoemulsion was of a sufficiently low particle size (307,4 ± 0,5 nm) and homogeneity (PDI = 0.270 ± 0.002) for skin application, and that its characteristics were not changed by its incorporation into the gel. A shear-thinning plastic flow behavior was seen for the Q10-nanoemulsion gel. The stress test as well as storage at 20±2 °C and 40 °C did not change the rheological parameters of the gel. However, Q10-content decreased in the Q10-loaded nanoemulsion gel, but less compared to the Q10-gel. The developed Q10-nanoemulsion gel was able to significantly decrease TEWL compared to untreated skin (control), while it was not able, without the addition of a moisturizing agent (hyaluronic acid) and emollient (C12-15 alkyl benzoate) to increase skin hydration compared to control. Thus, besides the addition of a Q10-nanoemulsion into a hydrogel, it is necessary to add moisturizers and/or emollients to increase skin hydration.

Detection of fragrances on the skin and study of their interaction using infrared and Raman spectroscopy

Nowadays, fragrances belong to the widely used cosmetics. Their composition is designed in a way that it evolves and changes over time. In this work, the effect of fragrances on the skin was studied – the interactions between pig skin samples and fragrances and the possibility of their detection and mutual differentiation. Non-invasive techniques of vibrational spectroscopy were used to obtain the data, namely FT-IR spectroscopy with attenuated total reflection accessory and Raman microspectroscopy. Vibrational spectra were measured within 8 h with different time intervals and after 22 h from the application of fragrance for FT-IR and Raman measurements, respectively. The obtained spectra were pre‑processed and subsequently evaluated by multivariate statistical methods. The study showed that skin treated by fragrances is well distinguishable from untreated skin, even after 22 h. In addition, it is possible to differentiate individual fragrances from each other; therefore, the use of spectroscopical techniques could be a potential tool for forensic analysis of fragrances.

Dupilumab normalizes correlates of lysosomal function in atopic dermatitis

AbstractBackgroundAtopic dermatitis (AD) is characterized by skin barrier dysfunction and immune dysregulation. Autophagy, which is important for the epidermal differentiation, is impaired in AD. The treatment with dupilumab, an interleukin (IL)‐4/IL‐13 receptor blocker, has been shown to reduce skin inflammation and restore the skin barrier.ObjectivesThis study aimed to investigate the effect of dupilumab on the expression of key proteins involved in autophagy and lysosomal degradation.MethodsWe performed immunofluorescence staining and microscopic analyses of skin specimens of AD patients, taken before and under (6–10 weeks) therapy with dupilumab, to investigate the expression of autophagy‐related (ATG) 5 and ATG7 proteins, beclin‐1, microtubule‐associated protein light chain 3 (LC3B), sequestosome‐1 (p62), lysosomal proteases (cathepsins B, D and L), serine protease inhibitors (SERPINB3, SERPINB4) as well as IL‐33 and thymic stromal lymphopoietin (TSLP).ResultsThe expression of LC3B and p62 as well as SERPINB3 and SERPINB4 was highly increased in untreated AD skin compared to non‐lesional skin and normal skin and decreased upon dupilumab therapy. In contrast, the AD‐associated increased expression of both ATG5 and ATG7 further increased under therapy. Before therapy, cathepsin D and L expression levels were significantly lower compared to normal skin, but increased following the initiation of dupilumab therapy. The increased expression of IL‐33 and TSLP in the epidermis of AD patients correlated with that of LC3B and p62.ConclusionsOur study provides further evidence that autophagy is inhibited in lesional AD skin owing to lysosomal dysfunction. Upon dupilumab therapy, a restoration of dysregulated key players of autophagy is observed.

Development of a Novel Self-Dissolving Microneedle-Assisted Percutaneous Delivery System of Diacerein through Solid Dispersion Gel: Solubility Enhancement, Proof of Anti-inflammatory Activity and Safety.

Diacerein, an osteoarthiritis drug, experiences slow topical permeation due to limited solubility. Additionally, it shows a laxative effect due to acid/base hydrolysis of the drug in the colon. Diacerein solubility was improved to increase percutaneous drug delivery. To improve saturation solubility of the drug, Diacerein was pre-treated with Polysorbate 80 aqueous solution (1% v/v) to obtain lyophilized powder after wet milling or formulated as solid dispersion using PEG 4000 by fusion method. The lyophilized Diacerein in hydroxypropyl methylcellulose (HPMC 8% w/w) and polyvinyl pyrrolidone (PVP 30% w/w) matrix, with PEG 400 as co-solvent, provided an optimized array. The solid dispersion was loaded in the CMC based gel for subsequent administration on dissolving microneedle-treated skin. The addition of PEG 400 increased Diacerein loading in microneedles to 390.35±4.28 μg per array. The lyophilized drug displayed amorphous characteristics in the dissolving microneedles as per XRD analysis. SEM photographs showed uniformity in the surface topology of microneedles. The needles showed rapid polymer dissolution within 5 minutes, whereas methylene-blue distribution confirmed the formation of microcavities in excised rat skin. The drug-loaded arrays showed better permeation (74.39%) and skin deposition (15.75%) after 24 hours, however, ⁓12% of Diacerein remained in the baseplate. This led to the tailoring of CMC-based gel (3% w/v) containing 0.4% solid dispersion of Diacerein. When compared to untreated skin, the gel improved permeation rate by 2.43 folds through aqueous microchannels generated by dissolving microneedle pre-treatment and allowed 98% drug permeation. The quasi-Fickian diffusion mechanism was found to drive ex vivo release kinetics, with a shorter lag time (0.88 h) and higher flux (26.65 μg/sq.cm.h). Microneedle-assisted Diacerein gel showed a positive anti-inflammatory effect in the paw edema model and reduced diarrheal episodes in comparison to the marketed oral formulation. The gel showed desired characteristics at 5°C±2°C when tested under accelerated stability conditions. The present study reports for the first time the verification of efficacy and safety to advocate the suitability of Diacerein for percutaneous delivery through dissolving microneedle-treated skin.