[Distinguishing human characteristics based on hair metabolomics and proteomics: a review]

Human hair, a kind of natural fiber mainly composed of keratin and keratin-associated proteins, is a good biological sample that can be used to characterize the status of the body in a certain period of time. It is of highly importance in the detection of drugs, alcohol and stimulants because of the advantages of low cost, easy collection, easy transportation and storage. Proteomics is an emerging technology widely used in the field of life sciences to study protein expression and regulation at the holistic level. Investigating the composition and dynamic changes of hair proteins in different populations would have great potential in finding disease markers and distinguishing personal traits. In this paper, the structure and composition of hair, the changes of hair composition under psychological stress, and the research progress of hair proteomics were comprehensively reviewed. This will help using hair proteomics to identify body characteristics.

Keratin Promotes Differentiation of Keratinocytes Seeded on Collagen/Keratin Hydrogels

Keratinocytes undergo a complex process of differentiation to form the stratified stratum corneum layer of the skin. In most biomimetic skin models, a 3D hydrogel fabricated out of collagen type I is used to mimic human skin. However, native skin also contains keratin, which makes up 90% of the epidermis and is produced by the keratinocytes present. We hypothesized that the addition of keratin (KTN) in our collagen hydrogel may aid in the process of keratinocyte differentiation compared to a pure collagen hydrogel. Keratinocytes were seeded on top of a 100% collagen or 50/50 C/KTN hydrogel cultured in either calcium-free (Ca-free) or calcium+ (Ca+) media. Our study demonstrates that the addition of keratin and calcium in the media increased lysosomal activity by measuring the glucocerebrosidase (GBA) activity and lysosomal distribution length, an indication of greater keratinocyte differentiation. We also found that the presence of KTN in the hydrogel also increased the expression of involucrin, a differentiation marker, compared to a pure collagen hydrogel. We demonstrate that a combination (i.e., containing both collagen and kerateine or “C/KTN”) hydrogel was able to increase keratinocyte differentiation compared to a pure collagen hydrogel, and the addition of calcium further increased the differentiation of keratinocytes. This multi-protein hydrogel shows promise in future models or treatments to increase keratinocyte differentiation into the stratum corneum.

The mRNA Expression Profile of Psoriatic Lesion Distinct from Non-Lesion

Purpose

Psoriasis is a chronic recurring autoimmune skin disease with a complex etiology and chronic progression; however, its molecular mechanisms remain unclear.

Patients and Methods

We performed transcriptomic analysis to profile the mRNA expression of psoriatic lesions (PL) and non-lesion (NL) tissues from psoriasis patients along with normal skin from healthy donors. RT-qPCR was used to validate the mRNA expression profiles.

Results

A total of 237 differentially expressed genes were screened and identified by RNA sequencing. GO and KEGG analysis indicated that these DEGs were enriched in the PPAR signaling pathway and intermediate filament cytoskeleton. For PPAR signaling pathway, the expression of five genes, including ADIPOQ, AQP7, PLIN1, FABP4 and LPL, were all significantly decreased in psoriatic lesions compared to normal skin by RT-qPCR. There is a clear difference between psoriatic lesions and non-lesion in the expression of ADIPOQ, AQP7 and LPL. For intermediate filament cytoskeleton, including KRT27, KRT25, KRT71, KRT86 and KRT85 were significantly decreased in the psoriasis lesions, showing agreement with the RNA-seq data.

Conclusion

This study revealed a significant difference between the mRNA expression profiles of PL, NL tissue and normal skin.

Large Unruptured Perineal Epidermoid Cyst: A Rare Case

Perineal epidermoid lesions are uncommon, with only a few research papers accessible on the subject. Because these lesions are varied in origin and can range from benign to malignant, it can be difficult to tell them apart. A wide variety of lesions are evaluated in the differential diagnosis of perineal cystic lesions, however perineal epidermoid cyst is uncommon. An epidermoid cyst is a benign ectodermal congenital abnormality. Epidermoid cysts can be found all over the body, however, they are uncommon in the perineal area. We discuss a case of a perineal epidermoid cyst in an adult female presenting to the general surgery department with painful perineal swelling. The patient was advised for an ultrasound (US) and MRI for further evaluation and the findings are reported.

A Ca2+-Mediated Switch of Epiplakin from a Diffuse to Keratin-Bound State Affects Keratin Dynamics

Keratins exert important structural but also cytoprotective functions. They have to be adaptable to support cellular homeostasis. Epiplakin (EPPK1) has been shown to decorate keratin filaments in epithelial cells and to play a protective role under stress, but the mechanism is still unclear. Using live-cell imaging of epithelial cells expressing fluorescently tagged EPPK1 and keratin, we report here an unexpected dynamic behavior of EPPK1 upon stress. EPPK1 was diffusely distributed throughout the cytoplasm and not associated with keratin filaments in living cells under standard culture conditions. However, ER-, oxidative and UV-stress, as well as cell fixation, induced a rapid association of EPPK1 with keratin filaments. This re-localization of EPPK1 was reversible and dependent on the elevation of cytoplasmic Ca²⁺ levels. Moreover, keratin filament association of EPPK1 led to significantly reduced keratin dynamics. Thus, we propose that EPPK1 stabilizes the keratin network in stress conditions, which involve increased cytoplasmic Ca²⁺.

Protein Contaminants Matter: Building Universal Protein Contaminant Libraries for DDA and DIA Proteomics

Mass spectrometry-based proteomics is constantly challenged by the presence of contaminant background signals. In particular, protein contaminants from reagents and sample handling are almost impossible to avoid. For data-dependent acquisition (DDA) proteomics, an exclusion list can be used to reduce the influence of protein contaminants. However, protein contamination has not been evaluated and is rarely addressed in data-independent acquisition (DIA). How protein contaminants influence proteomic data is also unclear. In this study, we established new protein contaminant FASTA and spectral libraries that are applicable to all proteomic workflows and evaluated the impact of protein contaminants on both DDA and DIA proteomics. We demonstrated that including our contaminant libraries can reduce false discoveries and increase protein identifications, without influencing the quantification accuracy in various proteomic software platforms. With the pressing need to standardize proteomic workflow in the research community, we highly recommend including our contaminant FASTA and spectral libraries in all bottom-up proteomic data analysis. Our contaminant libraries and a step-by-step tutorial to incorporate these libraries in various DDA and DIA data analysis platforms can be valuable resources for proteomic researchers, freely accessible at https://github.com/HaoGroup-ProtContLib.

Optimization of Conditions for Feather Waste Biodegradation by Geophilic Trichophyton ajelloi Fungal Strains towards Further Agricultural Use

The aim of the study was to optimize culture conditions and medium composition to accelerate the biodegradation of chicken feather waste by keratinolytic soil strains of Trichophyton ajelloi, which are poorly known in this respect, as well as to propose hitherto unconsidered culture conditions for these fungi in order to obtain a biopreparation with a high fertilization value. Different pH of the medium, incubation temperatures, amounts of chicken feathers, additional carbon sources, and culture methods were tested. The process of optimizing keratin biodegradation was evaluated in terms of measuring the activity of keratinase, protease, disulfide reductase, concentration of released soluble proteins and peptides, total pool of amino acids, ammonium and sulfate ions, changes in medium pH, and feather weight loss. It was found that the studied fungal strains were capable of decomposing and mineralizing keratin from feather waste. Regarding the fertilizer value of the obtained hydrolysates, it was shown that the release of sulfate and ammonium ions was highest in a stationary culture containing 2% feathers with an initial pH of 4.5 and a temperature of 28 °C. Days 14-21 of the culture were indicated as the optimal culture time for these fungi to obtain biopreparations of high fertilizing value.

MRI of a middle ear cholesteatoma in a cat

A 9-year-old Maine coon cat presented with right-sided Horner and facial nerve paralysis. Magnetic resonance imaging (MRI) showed a heterogeneously contrast-enhancing mass occupying the right dorsolateral compartment of the tympanic cavity and extending into the ventromedial compartment, which was expanded and fluid filled. A ventral bulla osteotomy was performed to debulk the soft tissue mass. Histopathology revealed a cholesteatoma. The cat showed slow improvement of clinical signs and was euthanized eleven months postoperatively for unrelated causes. The MRI characteristics of middle ear cholesteatoma in the present case varied from those described in humans and dogs.

Congenital Prepubic Sinus as a Variant of Incomplete Urethral Dorsal Duplication: A Case Report with New Insights into its Immunohistochemical Characterization and a Comprehensive Literature Review

Congenital prepubic sinus (PS) is an extremely infrequent malformation consisting of a prepubic fistulous tract that classically does not communicate with the genitourinary system. Previous studies centered on its immunohistochemical characterization have shown inconsistent results, and the etiology has not been clarified. We present the case of a 2-year-old male who presented since birth with a fistulous orifice on the dorsum of the penis. He had no associated symptoms. Under general anesthesia, the fistulous tract was explored, and methylene blue was instilled through it. After cystoscopically verifying the absence of communication with the urethra, a complete resection of the lesion was performed. The immunohistochemical study showed positivity for low and high molecular weight keratins and a transitional pattern for keratin 7 and GATA3, with positivity at cul de sac level and negativity at proximal level. These findings suggest that this lesion is an incomplete dorsal duplication variant.

Preparation of MSNs@Keratin as pH/GSH dual responsive drug delivery system

Designing a drug delivery system that is responsive in a tumor microenvironment is important to potentiate the efficacy and reduce the side effects of antitumor drugs. In this study, the surface of mesoporous silica nanoparticles (MSNs) were aminated with 3-aminopropyl triethoxysilane (APTES) and then coupled with keratin, as a gatekeeper, to afford MSNs-NH₂@Keratin. The average sizes and morphologies of MSNs and MSNs-NH₂@Keratin were characterized with dynamic light scattering and transmission electron microscopy, respectively. The loading content and encapsulation efficiency of doxorubicin (DOX) were calculated to be 17.1 ± 1.7% and 71.3 ± 2.1%. Drug-loaded MSNs-NH₂@Keratin exhibited pH and glutathione (GSH) dual responsiveness under tumor microenvironment. The nanoparticles could be uptaken by tumor cells to effectively inhibit tumor cell growth. Moreover, the sizes of nanoparticle were stable in the serum. Collectively, our findings demonstrated the potential of DOX-loaded MSNs-NH₂@Keratin in the treatment of cancer.

Extrusion 3D printing of keratin protein hydrogels free of exogenous chemical agents

Keratins are a class of intermediate filament proteins that can be obtained from numerous sources including human hair. Materials fabricated from keratins offer desirable characteristics as scaffolds for tissue engineering, including intrinsic cell adhesion sequences and tunable degradation kinetics. The capacity to create 3D printed constructs from keratin-based bio-inks generates unique opportunities for spatial control of scaffold physicochemical properties to direct scaffold functions in ways not readily achieved through other means. The aim of this study was to leverage the controllable rheological properties of keratin hydrogels to create a strategy for extrusion 3D printing of keratin bio-inks without the use of exogenous rheological modifiers, crosslinking agents, or photocurable resins. The rheological properties of keratin hydrogels were tuned by varying two parameters: (a) the ratio of keratose (obtained by oxidative extraction of keratin) to kerateine (obtained by reductive extraction of keratin); and (b) the weight percentage of total keratin protein in the gel. A computational model of the dispensing nozzle for a commercially available extrusion 3D printer was developed to calculate the needed pneumatic printing pressures based on the known rheological properties of the gels. Keratin hydrogel constructs, of varying keratose/kerateine ratios and total keratin weight percentages, were 3D printed in cylindrical geometries via extrusion 3D printing. Rheology and degradation studies showed that gels with greater relative kerateine content exhibited greater flow resistance and slower degradation kinetics when submerged in phosphate buffered saline solution at 37 °C, owing to the presence of cysteine residues in kerateine and the capability of forming disulfide bonds. Total keratin weight percentage was found to influence gel yield stress, with possible implications for tuning filament fidelity. Findings from this work support the use of keratose/kerateine ratio and total keratin weight percentage as handles for modulating rheological characteristics of keratin hydrogels to enhance printability and control scaffold properties.

Evaluation of Keratin-Cellulose Blend Fibers as Precursors for Carbon Fibers

One main challenge to utilize cellulose-based fibers as the precursor for carbon fibers is their inherently low carbon yield. This study aims to evaluate the use of keratin in chicken feathers, a byproduct of the poultry industry generated in large quantities, as a natural charring agent to improve the yield of cellulose-derived carbon fibers. Keratin-cellulose composite fibers are prepared through direct dissolution of the pulp and feather keratin in the ionic liquid 1,5-diazabicyclo[4.3.0]non-5-enium acetate ([DBNH]OAc) and subsequent dry jet wet spinning (so-called Ioncell process). Thermogravimetric analysis reveals that there is an increase in the carbon yield by ∼53 wt % with 30 wt % keratin incorporation. This increase is comparable to the one observed for lignin-cellulose composite fibers, in which lignin acts as a carbon booster due to its higher carbon content. Keratin, however, reduces the mechanical properties of cellulose precursor fibers to a lesser extent than lignin. Keratin introduces nitrogen and induces the formation of pores in the precursor fibers and the resulting carbon fibers. Carbon materials derived from the keratin-cellulose composite fiber show potential for applications where nitrogen doping and pores or voids in the carbon are desirable, for example, for low-cost bio-based carbons for energy harvest or storage.

Valorization of Human Hair and Its Derivatives in Tissue Engineering: A Review

Human hair is a potential biomaterial for biomedical applications. Improper disposal of human hair may pose various adverse effects on the environment and human health. Therefore, proper management of human hair waste is pivotal. Human hair fiber and its derivatives offer various advantages as biomaterials such as biocompatibility, biodegradability, low toxicity, radical scavenging, electroconductivity, and intrinsic biological activity. Therefore, the favorable characteristics of human hair have rendered its usage in tissue engineering (TE) applications including skin, cardiac, nerve, bone, ocular, and periodontal. Moreover, the strategies by utilizing human hair as a biomaterial for TE applications may reduce the accumulation of human hair. Thus, it also improves human hair waste management while promoting natural, environmental-friendly, and nontoxic materials. Furthermore, promoting sustainable materials production will benefit human health and well-being. Hence, this article reviews and discusses human hair characteristics as sustainable biomaterials and their recent application in TE applications. Impact Statement This review article highlights the sustainability aspects of human hair as raw biomaterials and various elements of human hair that could potentially be used in tissue engineering (TE) applications. Furthermore, this article discusses numerous benefits of human hair, highlighting its value as biomaterials in bioscaffold development for TE applications. Moreover, this article reviews the role and effect of human hair in various TE applications, including skin, cardiac, nerve, bone, ocular, and periodontal.

Biodegradable Nonwovens with Poultry Feather Addition as a Method for Recycling and Waste Management

Geotextiles are used for separation, drainage, filtration and anti-erosion protection sealing, as well as to improve plant vegetation conditions. The research objective of this study was to verify the influence of the addition of poultry feathers on accelerating the biodegradation of nonwovens in cultivated soil. The tests were carried out in laboratory conditions and were based on the assessment of weight loss. The experiments confirmed the positive effects of the presence of waste that was rich in keratin on the time required for the biodegradation of the tested materials (the period of biodegradation was 8–24 weeks). Additionally, the influence of the biodegradation of the tested materials on the ecotoxicity was investigated and showed no negative effects on the microbiological activity (10⁶ cfu). The research also included the determination of the carbon to nitrogen ratio of the test medium (blank, 12–14:1; with feather addition, 19–20:1). A statistical analysis revealed a correlation between the mechanical properties and the period of biological decomposition. This research was an important step for the management of poultry feather waste in agricultural applications. The tested materials could be seen an alternative that meets all ecological criteria, which seems to be a golden solution that not only allows the delivery of important nutrients to the soil, but also manages waste in an environmentally safe manner.

High-Performance Wigs via the Langmuir-Blodgett Deposition of Keratin/Graphene Oxide Nanocomposite

Wigs provide a common service as hair accessories in people's daily life. However, the traditional wigs, regardless of the matrices derived from human hair or synthetic fibers, are faced with limitations such as short service life, dry and brittle texture, and static electricity. In this work, we described a new strategy for surface coating of wigs via the Langmuir-Blodgett (LB) technique using a nanocomposite composed of hair-derived keratin and graphene oxide (Ker/GO). In contrast to the conventionally used immersion method, this strategy achieved a significantly higher surface coverage with a close-packed structure and controlled deposition layers of the coating, thus delivering high performances, including greatly enhanced ultraviolet (UV) resistance, antistatic electricity, heat dissipation, hydroscopicity, and moisturizing ability, and durability against washing, for both the human hair and synthetic-fiber-based wigs.

Combining Image Restoration and Traction Force Microscopy to Study Extracellular Matrix-Dependent Keratin Filament Network Plasticity

Keratin intermediate filaments are dynamic cytoskeletal components that are responsible for tuning the mechanical properties of epithelial tissues. Although it is known that keratin filaments (KFs) are able to sense and respond to changes in the physicochemical properties of the local niche, a direct correlation of the dynamic three-dimensional network structure at the single filament level with the microenvironment has not been possible. Using conventional approaches, we find that keratin flow rates are dependent on extracellular matrix (ECM) composition but are unable to resolve KF network organization at the single filament level in relation to force patterns. We therefore developed a novel method that combines a machine learning-based image restoration technique and traction force microscopy to decipher the fine details of KF network properties in living cells grown on defined ECM patterns. Our approach utilizes Content-Aware Image Restoration (CARE) to enhance the temporal resolution of confocal fluorescence microscopy by at least five fold while preserving the spatial resolution required for accurate extraction of KF network structure at the single KF/KF bundle level. The restored images are used to segment the KF network, allowing numerical analyses of its local properties. We show that these tools can be used to study the impact of ECM composition and local mechanical perturbations on KF network properties and corresponding traction force patterns in size-controlled keratinocyte assemblies. We were thus able to detect increased curvature but not length of KFs on laminin-322 versus fibronectin. Photoablation of single cells in microprinted circular quadruplets revealed surprisingly little but still significant changes in KF segment length and curvature that were paralleled by an overall reduction in traction forces without affecting global network orientation in the modified cell groups irrespective of the ECM coating. Single cell analyses furthermore revealed differential responses to the photoablation that were less pronounced on laminin-332 than on fibronectin. The obtained results illustrate the feasibility of combining multiple techniques for multimodal monitoring and thereby provide, for the first time, a direct comparison between the changes in KF network organization at the single filament level and local force distribution in defined paradigms.

Promising essential oils/plant extracts in the prevention and treatment of dandruff pathogenesis

BACKGROUND

Dandruff is a scalp malady affecting predominantly the male populace. Topical agents and synthetic drugs used for dandruff treatment have specific side effects including burning at the application site, depression, dizziness, headache, itching or skin rash, nausea, stomach pain, vision change, vomiting, discoloration of hair, dryness or oiliness of the scalp and increased loss of hair. Thus, essential oils and extracts from plants could be valuable in the treatment and prevention of dandruff.

AIM & OBJECTIVE

This review aims to highlight current findings in dandruff occurrence, its etiology, promising plant essential oils/extracts, and novel treatment strategies. The main emphasis has been given on the anti-dandruff effect of essential oils and plant extracts to disrupt microbial growth. The proposed mechanism (s) of action, novel approaches used to perk up its biopharmaceutical properties, and topical application have been discussed.

RESULTS

The literature survey was done, bibliographic sources and research papers were retrieved from different search engines and databases, including SciFinder, PubMed, NCBI, Scopus, and Google Scholar. The selection of papers was accomplished based on exclusion and inclusion criteria. The scalp of diverse populations revealed an association of dandruff with microbial symbiosis, including Staphylococcus, Propionibacterium, Malassezia, and Candida as the pathogens responsible for the cause of dandruff. Topical antifungals are considered as the first line of treatment for dandruff including azoles, with clotrimazole (1%), ketoconazole (2%), and miconazole (2%). Other commonly used therapies integrate benzoyl peroxide, coal tar, glycerin, zinc pyrithione, lithium succinate/gluconate, salicylic acid, selenium disulfide/sulfide, sodium sulfacetamide, etc. However, these medicaments and chemicals are known to cause specific side effects. Alternative therapies, including tea tree oil, thyme, Aloe vera, Mentha have been reported to demonstrate anti-dandruff activity by disrupting the microbial growth associated with dandruff formation.

CONCLUSION

Overall, this review explains the occurrence of dandruff, its etiology, and the potential applicability of promising plant essential oils/extracts, and their novel treatment strategies. Further studies based on pre-clinical and clinical research are essential before making any conclusion about its efficacy in humans.

Chemistry and Analysis of Organic Compounds in Dinosaurs

This review provides an overview of organic compounds detected in non-avian dinosaur fossils to date. This was enabled by the development of sensitive analytical techniques. Non-destructive methods and procedures restricted to the sample surface, e.g., light and electron microscopy, infrared (IR) and Raman spectroscopy, as well as more invasive approaches including liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), time-of-flight secondary ion mass spectrometry, and immunological methods were employed. Organic compounds detected in samples of dinosaur fossils include pigments (heme, biliverdin, protoporphyrin IX, melanin), and proteins, such as collagens and keratins. The origin and nature of the observed protein signals is, however, in some cases, controversially discussed. Molecular taphonomy approaches can support the development of suitable analytical methods to confirm reported findings and to identify further organic compounds in dinosaur and other fossils in the future. The chemical properties of the various organic compounds detected in dinosaurs, and the techniques utilized for the identification and analysis of each of the compounds will be discussed.

Sustainable Applications of Animal Waste Proteins

Currently, the growth of the global population leads to an increase in demand for agricultural products. Expanding the obtaining and consumption of food products results in a scale up in the amount of by-products formed, the development of processing methods for which is becoming an urgent task of modern science. Collagen and keratin make up a significant part of the animal origin protein waste, and the potential for their biotechnological application is almost inexhaustible. The specific fibrillar structure allows collagen and keratin to be in demand in bioengineering in various forms and formats, as a basis for obtaining hydrogels, nanoparticles and scaffolds for regenerative medicine and targeted drug delivery, films for the development of biodegradable packaging materials, etc. This review describes the variety of sustainable sources of collagen and keratin and the beneficial application multiformity of these proteins.

Characterization of a Human Platelet Lysate-Loaded Keratin Hydrogel for Wound Healing Applications In Vitro

One of the promising approaches to facilitate healing and regenerative capacity includes the application of growth-factor-loaded biomaterials. Human platelet lysate (hPL) derived from platelet-rich plasma through a freeze-thaw process has been used as a growth factor rich therapeutic in many regenerative applications. To provide sustained local delivery of the hPL-derived growth factors such as epidermal growth factor (EGF), the hPL can be loaded into biomaterials that do not degrade rapidly in vivo. Keratin (KSO), a strong filamentous protein found in human hair, when formulated as a hydrogel, is shown to sustain the release of drugs and promote wound healing. In the current study, we created a KSO biomaterial that spontaneously forms a hydrogel when rehydrated with hPL that is capable of controlled and sustained release of pro-regenerative molecules. Our study demonstrates that the release of hPL is controlled by changing the KSO hydrogel and hPL-loading concentrations, with hPL loading concentrations having a greater effect in changing release profiles. In addition, the 15% KSO concentration proved to form a stable hydrogel, and supported cell proliferation over 3 days without cytotoxic effects in vitro. The hPL-loaded keratin hydrogels show promise in potential applications for wound healing with the sustained release of pro-regenerative growth factors with easy tailoring of hydrogel properties.

Capturing intermediate filament networks

Mapping intermediate filaments in three dimensions reveals that the organization of these filaments differs across cell types.

A Newly Isolated Strain Lysobacter brunescens YQ20 and Its Performance on Wool Waste Biodegradation

Wool keratin is difficult to degrade as comparing to feathers because of its tough secondary structure. In order to develop an approach for high-value utilization of wool fiber waste by keratinolytic microorganisms, which is produced from shearing, weaving, and industrial processing of wool, screening of wool-degrading bacterium with high degradation efficiency were performed in this study. To this end, Lysobacter brunescens YQ20 was identified and characterized. The optimized conditions for wool degradation were pH 9.0 and 37°C with 20% liquid volume of Erlenmeyer flask. After fermentation, 15 essential amino acids were detected when wool fiber waste was fermented. The total amino acids produced from 1% wool per hour were 13.7 mg/L. The concentration was 8.6-fold higher than that produced by the strain Stenotrophomonas maltophilia BBE11-1, which had previously been reported to have the highest wool-degrading capacity. Our study reports the first Lysobacter strain that exhibits efficient wool degradation and yields higher concentrations of amino acids than previously reported strains. Whole-genome sequencing indicated that there were 18 keratinase-like genes in the genome of YQ20, which exhibited a long evolutionary distance from those of Bacillus. Therefore, L. brunescens YQ20 may have applications in the environmentally friendly management of wool waste as fertilizer in agriculture.

Deletion of hypoxia-inducible factor prolyl 4-hydroxylase 2 in FoxD1-lineage mesenchymal cells leads to congenital truncal alopecia

Hypoxia-inducible factors (HIFs) induce numerous genes regulating oxygen homeostasis. As oxygen sensors of the cells, the HIF prolyl 4-hydroxylases (HIF-P4Hs) regulate the stability of HIFs in an oxygen-dependent manner. During hair follicle (HF) morphogenesis and cycling, the location of dermal papilla (DP) alternates between the dermis and hypodermis and results in varying oxygen levels for the DP cells. These cells are known to express hypoxia-inducible genes, but the role of the hypoxia response pathway in HF development and homeostasis has not been studied. Using conditional gene targeting and analysis of hair morphogenesis, we show here that lack of Hif-p4h-2 in Forkhead box D1 (FoxD1)-lineage mesodermal cells interferes with the normal HF development in mice. FoxD1-lineage cells were found to be mainly mesenchymal cells located in the dermis of truncal skin, including those cells composing the DP of HFs. We found that upon Hif-p4h-2 inactivation, HF development was disturbed during the first catagen leading to formation of epithelial-lined HF cysts filled by unorganized keratins, which eventually manifested as truncal alopecia. Furthermore, the depletion of Hif-p4h-2 led to HIF stabilization and dysregulation of multiple genes involved in keratin formation, HF differentiation, and HIF, transforming growth factor β (TGF-β), and Notch signaling. We hypothesize that the failure of HF cycling is likely to be mechanistically caused by disruption of the interplay of the HIF, TGF-β, and Notch pathways. In summary, we show here for the first time that HIF-P4H-2 function in FoxD1-lineage cells is essential for the normal development and homeostasis of HFs.

Nitric oxide-releasing polyurethane/S-nitrosated keratin mats for accelerating wound healing

Nitric oxide (NO) plays an important role in wound healing, due to its ability to contract wound surfaces, dilate blood vessels, participate in inflammation as well as promote collagen synthesis, angiogenesis and fibroblast proliferation. Herein, keratin was first nitrosated to afford S-nitrosated keratin (KSNO). As a NO donor, KSNO was then co-electrospun with polyurethane (PU). These as-spun PU/KSNO biocomposite mats could release NO sustainably for 72 h, matching the renewal time of the wound dressing. Moreover, these mats exhibited excellent cytocompatibility with good cell adhesion and cell migration. Further, the biocomposite mats exhibited antibacterial properties without inducing severe inflammatory responses. The wound repair in vivo demonstrated that these mats accelerated wound healing by promoting tissue formation, collagen deposition, cell migration, re-epithelialization and angiogenesis. Overall, PU/KSNO mats may be promising candidates for wound dressing.

Transdermal Enhancement Strategy of Lappaconitine: Alteration of Keratin Configuration by Counter-Ion

The objective of this study was to develop a lappaconitine (LA) transdermal patch with counter-ion to increase the transdermal permeability of the drug, and a theory of counter-ion altering the conformation of the skin keratin was put forward based on the in vitro skin permeation study and physicochemical properties of ion-pairs. Formulation factors including pressure sensitive adhesives (PSAs), drug-loading, counter-ions and molar ratios of counter-ion were screened by in vitro skin permeation study. The optimized formulation was composed of 7% LA, 1.5 mole cinnamic acid and AAOH (PSA containing hydroxyl group synthesized by our laboratory) as an adhesive matrix. The optimized patch was evaluated by the pharmacokinetic and analgesic pharmacodynamic studies. AUC_0-t and pain inhibition ratio of the optimized patch were 2450.40 ± 848.52 h ng/mL and 81.18%, which showed good absorption into the skin and excellent analgesic effect. The mechanism of facilitated transdermal drug permeation by counter-ion was investigated by ATR-FTIR, thermal analysis, FTIR, XPS and molecular docking. The results indicated that after the formation of ion-pairs, the excess counter-ions would alter the conformation of the skin keratin, thus increasing the transdermal penetration of LA. In conclusion, the LA patch was successfully optimized, and the effect of counter-ions on the skin was clarified at the molecular level. These findings provided additional references for the application of counter-ion in the transdermal drug delivery system.