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1.
J Enzyme Inhib Med Chem ; 35(1): 824-830, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32216477

RESUMEN

The ß-carbonic anhydrase (CA, EC 4.2.1.1) from the genome of the opportunistic pathogen Malassezia restricta (MreCA), which was recently cloned and characterised, herein has been investigated for enzymatic activation by a panel of amines and amino acids. Of the 24 compounds tested in this study, the most effective MreCA activators were L-adrenaline (KA of 15 nM), 2-aminoethyl-piperazine/morpholine (KAs of 0.25-0.33 µM), histamine, L-4-amino-phenylalanine, D-Phe, L-/D-DOPA, and L-/D-Trp (KAs of 0.32 - 0.90 µM). The least effective activators were L-/D-Tyr, L-Asp, L-/D-Glu, and L-His, with activation constants ranging between 4.04 and 12.8 µM. As MreCA is involved in dandruff and seborrhoeic dermatitis, these results are of interest to identify modulators of the activity of enzymes involved in the metabolic processes of such fungi.


Asunto(s)
Aminas/metabolismo , Aminoácidos/metabolismo , Anhidrasas Carbónicas/metabolismo , Malassezia/enzimología , Aminas/química , Aminoácidos/química , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/aislamiento & purificación , Estructura Molecular
2.
Proc Natl Acad Sci U S A ; 114(20): 5147-5152, 2017 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-28465437

RESUMEN

Shear thickening in dense particulate suspensions was recently proposed to be driven by the activation of friction above an onset stress needed to overcome repulsive forces between particles. Testing this scenario represents a major challenge because classical rheological approaches do not provide access to the frictional properties of suspensions. Here we adopt a different strategy inspired by pressure-imposed configurations in granular flows that specifically gives access to this information. By investigating the quasi-static avalanche angle, compaction, and dilatancy effects in different nonbuoyant suspensions flowing under gravity, we demonstrate that particles in shear-thickening suspensions are frictionless under low confining pressure. Moreover, we show that tuning the range of the repulsive force below the particle roughness suppresses the frictionless state and also the shear-thickening behavior of the suspension. These results, which link microscopic contact physics to the suspension macroscopic rheology, provide direct evidence that the recent frictional transition scenario applies in real suspensions.

3.
Int J Mol Sci ; 20(10)2019 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-31108925

RESUMEN

The cloning, purification, and initial characterization of the ß-carbonic anhydrase (CA, EC 4.2.1.1) from the genome of the opportunistic pathogen Malassezia restricta (MreCA), which a fungus involved in dandruff and seborrheic dermatitis (SD), is reported. MreCA is a protein consisting of 230 amino acid residues and shows high catalytic activity for the hydration of CO2 into bicarbonate and protons, with the following kinetic parameters: kcat of 1.06 × 106 s-1 and kcat/KM of 1.07 × 108 M-1 s-1. It is also sensitive to inhibition by the sulfonamide acetazolamide (KI of 50.7 nM). Phylogenetically, MreCA and other CAs from various Malassezia species seem to be on a different branch, distinct from that of other ß-CAs found in fungi, such as Candida spp., Saccharomyces cerevisiae, Aspergillus fumigatus, and Sordaria macrospora, with only Cryptococcus neoformans and Ustilago maydis enzymes clustering near MreCA. The further characterization of this enzyme and the identification of inhibitors that may interfere with its life cycle might constitute new strategies for fighting dandruff and SD.


Asunto(s)
Caspa/microbiología , Dermatitis Seborreica/microbiología , Proteínas Fúngicas/aislamiento & purificación , Malassezia/enzimología , Dióxido de Carbono/metabolismo , Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/aislamiento & purificación , Clonación Molecular , Proteínas Fúngicas/genética , Humanos , Filogenia , Sulfonamidas/farmacología
4.
J Biol Chem ; 289(18): 12647-56, 2014 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-24627479

RESUMEN

Malassezia species are ubiquitous residents of human skin and are associated with several diseases such as seborrheic dermatitis, tinea versicolor, folliculitis, atopic dermatitis, and scalp conditions such as dandruff. Host-Malassezia interactions and mechanisms to evade local immune responses remain largely unknown. Malassezia restricta is one of the most predominant yeasts of the healthy human skin, its cell wall has been investigated in this paper. Polysaccharides in the M. restricta cell wall are almost exclusively alkali-insoluble, showing that they play an essential role in the organization and rigidity of the M. restricta cell wall. Fractionation of cell wall polymers and carbohydrate analyses showed that the polysaccharide core of the cell wall of M. restricta contained an average of 5% chitin, 20% chitosan, 5% ß-(1,3)-glucan, and 70% ß-(1,6)-glucan. In contrast to other yeasts, chitin and chitosan are relatively abundant, and ß-(1,3)-glucans constitute a minor cell wall component. The most abundant polymer is ß-(1,6)-glucans, which are large molecules composed of a linear ß-(1,6)-glucan chains with ß-(1,3)-glucosyl side chain with an average of 1 branch point every 3.8 glucose unit. Both ß-glucans are cross-linked, forming a huge alkali-insoluble complex with chitin and chitosan polymers. Data presented here show that M. restricta has a polysaccharide organization very different of all fungal species analyzed to date.


Asunto(s)
Pared Celular/química , Dermatomicosis/microbiología , Malassezia/química , Polisacáridos/análisis , Quitina/análisis , Quitina/química , Cromatografía Liquida , Humanos , Espectroscopía de Resonancia Magnética , Polisacáridos/química , Proteoglicanos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , beta-Glucanos/análisis , beta-Glucanos/química
5.
Exp Dermatol ; 24(5): 398-400, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25739873

RESUMEN

Dandruff is a scalp disorder characterized by the formation of flaky white-yellowish scales due to an altered proliferation and differentiation status; a disrupted barrier function; a decrease in the level of hydration and of natural moisturizing factors (NMF) in the scalp, with a persistent and relapsing inflammatory condition. It was recently reported that an imbalance between bacterial and fungal species colonizing the scalp of French volunteers was associated with dandruff condition. The purpose of the present study was to analyze the major bacterial and fungal species present on the scalp surface of Chinese volunteers and to investigate possible region-related variation in the microbiota linked to dandruff condition. The data obtained from the Chinese populations were highly similar to those obtained in France, confirming that dandruff scalps are associated with a higher incidence of Malassezia restricta and Staphylococcal sp. The ratios of Malassezia to Propionibacterium and Propionibacterium to Staphylococcus were also significantly higher in the dandruff volunteers as compared to normal volunteers, suggesting that equilibrium between the major bacterial and fungal taxa found on the normal scalps is perturbed in the dandruff scalps. The main difference between the French and Shanghai subjects was in their Staphylococcal biota. The results obtained in China and in France suggest that targeting one particular Malassezia sp. by antifungals instead of using large spectrum antifungals and rebalancing the dandruff scalp microbiota could be common approach to improve dandruff condition in the two countries.


Asunto(s)
Caspa/microbiología , Adulto , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Estudios de Casos y Controles , China , Femenino , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Humanos , Masculino , Microbiota/genética , Cuero Cabelludo/microbiología , Adulto Joven
6.
Nature ; 460(7259): 1117-21, 2009 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-19713928

RESUMEN

The air we breathe is filled with thousands of fungal spores (conidia) per cubic metre, which in certain composting environments can easily exceed 10(9) per cubic metre. They originate from more than a hundred fungal species belonging mainly to the genera Cladosporium, Penicillium, Alternaria and Aspergillus. Although these conidia contain many antigens and allergens, it is not known why airborne fungal microflora do not activate the host innate immune cells continuously and do not induce detrimental inflammatory responses following their inhalation. Here we show that the surface layer on the dormant conidia masks their recognition by the immune system and hence prevents immune response. To explore this, we used several fungal members of the airborne microflora, including the human opportunistic fungal pathogen Aspergillus fumigatus, in in vitro assays with dendritic cells and alveolar macrophages and in in vivo murine experiments. In A. fumigatus, this surface 'rodlet layer' is composed of hydrophobic RodA protein covalently bound to the conidial cell wall through glycosylphosphatidylinositol-remnants. RodA extracted from conidia of A. fumigatus was immunologically inert and did not induce dendritic cell or alveolar macrophage maturation and activation, and failed to activate helper T-cell immune responses in vivo. The removal of this surface 'rodlet/hydrophobin layer' either chemically (using hydrofluoric acid), genetically (DeltarodA mutant) or biologically (germination) resulted in conidial morphotypes inducing immune activation. All these observations show that the hydrophobic rodlet layer on the conidial cell surface immunologically silences airborne moulds.


Asunto(s)
Antígenos Fúngicos/inmunología , Esporas Fúngicas/inmunología , Traslado Adoptivo , Microbiología del Aire , Alérgenos , Animales , Antígenos Fúngicos/química , Antígenos Fúngicos/genética , Antígenos de Plantas , Aspergillus fumigatus/química , Aspergillus fumigatus/inmunología , Aspergillus fumigatus/fisiología , Linfocitos T CD4-Positivos/inmunología , Catepsinas , Células Cultivadas , Células Dendríticas/citología , Células Dendríticas/inmunología , Células Dendríticas/trasplante , Proteínas Fúngicas , Humanos , Ácido Fluorhídrico/química , Sistema Inmunológico/inmunología , Activación de Linfocitos , Macrófagos Alveolares/inmunología , Ratones , Ratones Endogámicos C57BL , Esporas Fúngicas/química , Esporas Fúngicas/genética
7.
J Dermatol ; 51(4): 518-525, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38217001

RESUMEN

Dandruff and scalp discomfort are common concerns for women and men in Africa. Moreover, women with afro-textured hair are prone to scalp discomfort owing to irregular hair washing, frequent use of oil-based products on their scalp, and harsh chemical treatments. Current literature does not, however, provide data on the pathophysiological mechanisms of these conditions in this population. In this study, we investigated the mechanisms behind scalp discomfort and dandruff in women of African descent before and after hair washing. We conducted the in Durban, South Africa, over a 3-week period with 60 women of African descent aged 20-40 years. The respondents were equally divided into a "dandruff" and a "no dandruff" group, based on clinical grading of adherent dandruff by a dermatologist. Malassezia spp. and bacterial loads were quantified by quantitative polymerase chain reaction. Evaluations of scalp condition and sample collection were performed at five time points during the 3 weeks. Data on discomfort symptoms were collected via a self-assessment questionnaire. We observed that the dandruff severity peaked at the end of the first week after hair washing and plateaued from thereon in both groups. Dandruff was associated with higher Malassezia and bacterial load counts and there was a direct correlation between the Malassezia spp. load and dandruff score. Via self-assessment questionnaire responses submitted by participants, we observed that itching was the most pronounced scalp discomfort, compared with the sensation of tingling and burning at baseline, while an improvement of the scalp symptoms of dandruff and itch was observed in both groups after one hair wash. The study also showed that higher colonization with Malassezia spp. and bacteria is associated with dandruff independently of the time point, confirming a scalp microbiome contribution to the dandruff pathophysiology in the study population. The benefits of washing were, however, not sustained after 1 week and we thus recommend weekly hair washing for long-term management of dandruff and scalp itchiness in this population.


Asunto(s)
Caspa , Malassezia , Pitiriasis , Masculino , Humanos , Femenino , Caspa/terapia , Cuero Cabelludo , Sudáfrica , Cabello , Prurito/etiología , Prurito/terapia , Parestesia
8.
J Antimicrob Chemother ; 68(6): 1285-96, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23378416

RESUMEN

OBJECTIVES: Candida albicans is the most prevalent fungal pathogen of humans, causing a wide range of infections from harmless superficial to severe systemic infections. Improvement of the antifungal arsenal is needed since existing antifungals can be associated with limited efficacy, toxicity and antifungal resistance. Here we aimed to identify compounds that act synergistically with echinocandin antifungals and that could contribute to a faster reduction of the fungal burden. METHODS: A total of 38 758 compounds were tested for their ability to act synergistically with aminocandin, a ß-1,3-glucan synthase inhibitor of the echinocandin family of antifungals. The synergy between echinocandins and an identified hit was studied with chemogenomic screens and testing of individual Saccharomyces cerevisiae and C. albicans mutant strains. RESULTS: We found that colistin, an antibiotic that targets membranes in Gram-negative bacteria, is synergistic with drugs of the echinocandin family against all Candida species tested. The combination of colistin and aminocandin led to faster and increased permeabilization of C. albicans cells than either colistin or aminocandin alone. Echinocandin susceptibility was a prerequisite to be able to observe the synergy. A large-scale screen for genes involved in natural resistance of yeast cells to low doses of the drugs, alone or in combination, identified efficient sphingolipid and chitin biosynthesis as necessary to protect S. cerevisiae and C. albicans cells against the antifungal combination. CONCLUSIONS: These results suggest that echinocandin-mediated weakening of the cell wall facilitates colistin targeting of fungal membranes, which in turn reinforces the antifungal activity of echinocandins.


Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Colistina/farmacología , Equinocandinas/farmacología , Animales , Antifúngicos/uso terapéutico , Candida/genética , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , Permeabilidad de la Membrana Celular/efectos de los fármacos , Pared Celular/efectos de los fármacos , Quitina/biosíntesis , Colistina/uso terapéutico , Colorantes , Sinergismo Farmacológico , Equinocandinas/uso terapéutico , Biblioteca de Genes , Aptitud Genética , Genotipo , Técnicas de Dilución del Indicador , Lipopéptidos/farmacología , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Mutación/genética , Propidio , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Esfingolípidos/biosíntesis
9.
Front Immunol ; 14: 1098160, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37304256

RESUMEN

Introduction: Staphylococcus epidermidis is a commensal bacterium ubiquitously present on human skin. This species is considered as a key member of the healthy skin microbiota, involved in the defense against pathogens, modulating the immune system, and involved in wound repair. Simultaneously, S. epidermidis is the second cause of nosocomial infections and an overgrowth of S. epidermidis has been described in skin disorders such as atopic dermatitis. Diverse isolates of S. epidermidis co-exist on the skin. Elucidating the genetic and phenotypic specificities of these species in skin health and disease is key to better understand their role in various skin conditions. Additionally, the exact mechanisms by which commensals interact with host cells is partially understood. We hypothesized that S. epidermidis isolates identified from different skin origins could play distinct roles on skin differentiation and that these effects could be mediated by the aryl hydrocarbon receptor (AhR) pathway. Methods: For this purpose, a library of 12 strains originated from healthy skin (non-hyperseborrheic (NH) and hyperseborrheic (H) skin types) and disease skin (atopic (AD) skin type) was characterized at the genomic and phenotypic levels. Results and discussion: Here we showed that strains from atopic lesional skin alter the epidermis structure of a 3D reconstructed skin model whereas strains from NH healthy skin do not. All strains from NH healthy skin induced AhR/OVOL1 path and produced high quantities of indole metabolites in co-culture with NHEK; especially indole-3-aldehyde (IAld) and indole-3-lactic acid (ILA); while AD strains did not induce AhR/OVOL1 path but its inhibitor STAT6 and produced the lowest levels of indoles as compared to the other strains. As a consequence, strains from AD skin altered the differentiation markers FLG and DSG1. The results presented here, on a library of 12 strains, showed that S. epidermidis originated from NH healthy skin and atopic skin have opposite effects on the epidermal cohesion and structure and that these differences could be linked to their capacity to produce metabolites, which in turn could activate AHR pathway. Our results on a specific library of strains provide new insights into how S. epidermidis may interact with the skin to promote health or disease.


Asunto(s)
Dermatitis Atópica , Staphylococcus epidermidis , Humanos , Promoción de la Salud , Receptores de Hidrocarburo de Aril , Piel
10.
Microbiome ; 11(1): 124, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37264459

RESUMEN

BACKGROUND: The effects of air pollutants, particularly polycyclic aromatic hydrocarbons (PAHs), on the skin microbiome remain poorly understood. Thus, to better understand the interplay between air pollutants, microbiomes, and skin conditions, we applied metagenomics and metabolomics to analyze the effects of PAHs in air pollution on the skin microbiomes of over 120 subjects residing in two cities in China with different levels of air pollution. RESULTS: The skin microbiomes differentiated into two cutotypes (termed 1 and 2) with distinct taxonomic, functional, resistome, and metabolite compositions as well as skin phenotypes that transcended geography and host factors. High PAH exposure was linked to dry skin and cutotype 2, which was enriched with species with potential biodegradation functions and had reduced correlation network structure integrity. The positive correlations identified between dominant taxa, key functional genes, and metabolites in the arginine biosynthesis pathway in cutotype 1 suggest that arginine from bacteria contributes to the synthesis of filaggrin-derived natural moisturizing factors (NMFs), which provide hydration for the skin, and could explain the normal skin phenotype observed. In contrast, no correlation with the arginine biosynthesis pathway was observed in cutotype 2, which indicates the limited hydration functions of NMFs and explains the observed dry skin phenotype. In addition to dryness, skin associated with cutotype 2 appeared prone to other adverse conditions such as inflammation. CONCLUSIONS: This study revealed the roles of PAHs in driving skin microbiome differentiation into cutotypes that vary extensively in taxonomy and metabolic functions and may subsequently lead to variations in skin-microbe interactions that affect host skin health. An improved understanding of the roles of microbiomes on skin exposed to air pollutants can aid the development of strategies that harness microbes to prevent undesirable skin conditions. Video Abstract.


Asunto(s)
Contaminantes Atmosféricos , Microbiota , Hidrocarburos Policíclicos Aromáticos , Piel/química , Contaminantes Atmosféricos/análisis , Biodegradación Ambiental , Microbiota/genética , Monitoreo del Ambiente
11.
Front Aging ; 4: 1304705, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38362046

RESUMEN

Introduction: During adulthood, the skin microbiota can be relatively stable if environmental conditions are also stable, yet physiological changes of the skin with age may affect the skin microbiome and its function. The microbiome is an important factor to consider in aging since it constitutes most of the genes that are expressed on the human body. However, severity of specific aging signs (one of the parameters used to measure "apparent" age) and skin surface quality (e.g., texture, hydration, pH, sebum, etc.) may not be indicative of chronological age. For example, older individuals can have young looking skin (young apparent age) and young individuals can be of older apparent age. Methods: Here we aim to identify microbial taxa of interest associated to skin quality/aging signs using a multi-study analysis of 13 microbiome datasets consisting of 16S rRNA amplicon sequence data and paired skin clinical data from the face. Results: We show that there is a negative relationship between microbiome diversity and transepidermal water loss, and a positive association between microbiome diversity and age. Aligned with a tight link between age and wrinkles, we report a global positive association between microbiome diversity and Crow's feet wrinkles, but with this relationship varying significantly by sub-study. Finally, we identify taxa potentially associated with wrinkles, TEWL and corneometer measures. Discussion: These findings represent a key step towards understanding the implication of the skin microbiota in skin aging signs.

12.
Eur J Dermatol ; 33(S1): 5-12, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37098773

RESUMEN

BACKGROUND: Dandruff is a chronic and relapsing scalp condition characterized by flaky scalp. Environmental and host factors (exposome) may alter the sebaceous gland activity, sebum composition, epidermal barrier function, and scalp microbiome balance, resulting in dandruff. Selenium disulfide (SeS2) improves the clinical signs of dandruff. OBJECTIVES: To investigate the mode of action of SeS2 shampoo during treatment and relapse phases. MATERIALS & METHODS: Two single-center studies assessed dandruff severity, subjective efficacy perception, microbial balance, microbiota diversity and sebum lipids. RESULTS: SeS2 significantly (p≤0.01) reduced scaling and led to a significant decrease of Malassezia and Staphylococcus spp. counts in both lesional and non-lesional areas, compared to the vehicle at D28 returning to baseline levels at D56. Cutibacterium spp. levels were not different between the SeS2 and the vehicle treatment groups but had significantly increased with SeS2 (p<0.001) in the lesional zone at D56. The ratio Malassezia spp./Cutibacterium spp. decreased significantly in lesional zones compared to baseline levels, at both D28 and D35 (p<0.001). The total squalene content significantly increased (p<0.05), whereas peroxided squalene had significantly decreased by almost 50% at D31. The ratio triglycerides/free fatty acids significantly (p<0.0001) increased, almost 5-fold, between D0 and D31. SeS2 shampoo was very well tolerated. CONCLUSION: SeS2 is beneficial in scalp dandruff, even after treatment interruption. It is well tolerated, rebalances the equilibrium between the main bacterial and fungal populations, and improves sebum quality.


Asunto(s)
Caspa , Malassezia , Microbiota , Humanos , Caspa/tratamiento farmacológico , Caspa/microbiología , Cuero Cabelludo , Sebo , Escualeno
13.
Antimicrob Agents Chemother ; 56(6): 3428-31, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22391552

RESUMEN

In vitro testing of Aspergillus fumigatus susceptibility to echinocandins has always been a challenge. Using a simple and quick colorimetric method to analyze the activity of inhibitors of ß-1,3-glucan synthesis, we found that the composition of the culture medium significantly influences glucan synthesis and consequently the antifungal properties of inhibitors of ß-1,3-glucan synthesis when they are tested alone or in combination with chitin synthase inhibitors.


Asunto(s)
Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/metabolismo , Medios de Cultivo/farmacología , beta-Glucanos/metabolismo , Caspofungina , Equinocandinas/farmacología , Glicósidos/farmacología , Lipopéptidos , Miconazol/farmacología , Pruebas de Sensibilidad Microbiana , Triterpenos/farmacología
14.
Pathogens ; 11(2)2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35215065

RESUMEN

The microbiome, as a community of microorganisms and their structural elements, genomes, metabolites/signal molecules, has been shown to play an important role in human health, with significant beneficial applications for gut health. Skin microbiome has emerged as a new field with high potential to develop disruptive solutions to manage skin health and disease. Despite an incomplete toolbox for skin microbiome analyses, much progress has been made towards functional dissection of microbiomes and host-microbiome interactions. A standardized and robust investigation of the skin microbiome is necessary to provide accurate microbial information and set the base for a successful translation of innovations in the dermo-cosmetic field. This review provides an overview of how the landscape of skin microbiome research has evolved from method development (multi-omics/data-based analytical approaches) to the discovery and development of novel microbiome-derived ingredients. Moreover, it provides a summary of the latest findings on interactions between the microbiomes (gut and skin) and skin health/disease. Solutions derived from these two paths are used to develop novel microbiome-based ingredients or solutions acting on skin homeostasis are proposed. The most promising skin and gut-derived microbiome interventional strategies are presented, along with regulatory, safety, industrial, and technical challenges related to a successful translation of these microbiome-based concepts/technologies in the dermo-cosmetic industry.

15.
J Cosmet Dermatol ; 21(5): 2215-2225, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34416081

RESUMEN

OBJECTIVE: Scalp seborrheic dermatitis (SD) is a chronic, relapsing, and inflammatory scalp disease. Studies indicate a global bacterial and fungal microbiota shift of scalp SD, as compared to healthy scalp. Ketoconazole and selenium disulfide (SeS2 ) improve clinical signs and symptoms in both scalp dandruff and SD. AIM: The main objective of this study was to investigate the changes in the scalp microbiota diversity and counts in subjects with scalp SD during a two-phase treatment period. MATERIAL AND METHODS: The scalp microbiota and clinical efficacy were investigated in 68 subjects with mild-to-moderate scalp SD after an initial one-month treatment with 2% ketoconazole, and after a 2-month maintenance phase, either with a 1% SeS2 -based shampoo or its vehicle. RESULTS: Thirty one subjects in the active and 37 subjects in the vehicle group participated. Ketoconazole provided an improvement of clinical symptoms (adherent (-1.75 p < 0.05), non-adherent (-1.5, p < 0.05)) flakes and erythema (scores 1.67-0.93, p < 0.001), in an increased fungal diversity and in a significant (p < 0.005) decrease of Malassezia spp. SeS2 provided an additional clinical improvement (-0.8; p = 0.0002 and -0.7; p = 0.0081 for adherent and non-adherent flakes, respectively, at Day 84) compared to the vehicle associated with a low Malassezia spp. count and an additional significant (p < 0.001) decrease of the Staphylococcus spp. level. CONCLUSION: Selenium disulfide provides an additional benefit on the scalp microbiota and in clinical symptoms of SD and dandruff after treatment with ketoconazole. The results confirm the role of Staphylococcus spp. in scalp SD and open possible perspectives for preventing relapses.


Asunto(s)
Caspa , Dermatitis Seborreica , Preparaciones para el Cabello , Malassezia , Microbiota , Dermatosis del Cuero Cabelludo , Caspa/tratamiento farmacológico , Dermatitis Seborreica/tratamiento farmacológico , Dermatitis Seborreica/microbiología , Preparaciones para el Cabello/efectos adversos , Humanos , Cetoconazol/uso terapéutico , Cuero Cabelludo , Dermatosis del Cuero Cabelludo/tratamiento farmacológico , Dermatosis del Cuero Cabelludo/microbiología , Compuestos de Selenio
16.
J Biol Chem ; 285(4): 2386-96, 2010 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-19948732

RESUMEN

A new HPLC method was developed to separate linear from beta(1-6)-branched beta(1-3)-glucooligosaccharides. This methodology has permitted the isolation of the first fungal beta(1-6)/beta(1-3)-glucan branching transglycosidase using a cell wall autolysate of Aspergillus fumigatus (Af). The encoding gene, AfBGT2 is an ortholog of AfBGT1, another transglycosidase of A. fumigatus previously analyzed (Mouyna, I., Hartland, R. P., Fontaine, T., Diaquin, M., Simenel, C., Delepierre, M., Henrissat, B., and Latgé, J. P. (1998) Microbiology 144, 3171-3180). Both enzymes release laminaribiose from the reducing end of a beta(1-3)-linked oligosaccharide and transfer the remaining chain to another molecule of the original substrate. The AfBgt1p transfer occurs at C-6 of the non-reducing end group of the acceptor, creating a kinked beta(1-3;1-6) linear molecule. The AfBgt2p transfer takes place at the C-6 of an internal group of the acceptor, resulting in a beta(1-3)-linked product with a beta(1-6)-linked side branch. The single Afbgt2 mutant and the double Afbgt1/Afbgt2 mutant in A. fumigatus did not display any cell wall phenotype showing that these activities were not responsible for the construction of the branched beta(1-3)-glucans of the cell wall.


Asunto(s)
Aspergillus fumigatus/enzimología , Glucano Endo-1,3-beta-D-Glucosidasa/aislamiento & purificación , Glucano Endo-1,3-beta-D-Glucosidasa/metabolismo , beta-Glucanos/aislamiento & purificación , beta-Glucanos/metabolismo , Aspergillus fumigatus/genética , Western Blotting , Pared Celular/enzimología , Celulasas/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Electroforesis en Gel de Poliacrilamida , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Glucano Endo-1,3-beta-D-Glucosidasa/genética , Glicosilación , Mutación , Resonancia Magnética Nuclear Biomolecular , Fenotipo
17.
Fungal Genet Biol ; 48(4): 418-29, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21184840

RESUMEN

A quintuple mutant was constructed to delete the entire family of the fungal/plant (class III) chitinases of Aspergillus fumigatus. Only a limited reduction in the total chitinolytic activity was seen for the different chitinase mutants including the quintuple mutant. In spite of this reduction in chitinolytic activity, no growth or germination defects were observed in these chitinase mutants. This result demonstrated that the fungal/plant chitinases do not have an essential role in the morphogenesis of A. fumigatus. A slight diminution of the growth during autolysis was seen for the quintuple mutant suggesting that class III chitinases may play only a nutritional role during this phase of the cycle, retarding fungal death.


Asunto(s)
Aspergillus fumigatus/enzimología , Quitinasas/metabolismo , Aspergillus fumigatus/citología , Aspergillus fumigatus/genética , Aspergillus fumigatus/crecimiento & desarrollo , Quitina/metabolismo , Quitinasas/genética , Eliminación de Gen , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo
18.
J Immunol ; 183(4): 2407-14, 2009 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-19625642

RESUMEN

The ability of the fungus Aspergillus fumigatus to activate, suppress, or subvert host immune response during life cycle in vivo through dynamic changing of cell wall structure and secretion implicates discriminative immune sensing of distinct fungal components. In this study, we have comparatively assessed secreted- and membrane-anchored proteins, glycolipids, and polysaccharides for the ability to induce vaccine-dependent protection in transplanted mice and Th cytokine production by human-specific CD4(+) T cell clones. The results show that the different fungal components are endowed with the distinct capacity to activate Th cell responses in mice and humans, with secreted proteins inducing Th2 cell activation, membrane proteins Th1/Treg, glycolipids Th17, and polysaccharides mostly IL-10 production. Of interest, the side-by-side comparison revealed that at least three fungal components (a protease and two glycosylphosphatidylinositol-anchored proteins) retained their immunodominant Th1/Treg activating potential from mice to humans. This suggests that the broadness and specificity of human T cell repertoire against the fungus could be selectively exploited with defined immunoactive Aspergillus Ags.


Asunto(s)
Aspergillus fumigatus/inmunología , Proteínas Fúngicas/fisiología , Vacunas Fúngicas/inmunología , Glucolípidos/fisiología , Polisacáridos/fisiología , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/microbiología , Animales , Antígenos Fúngicos/fisiología , Aspergilosis/inmunología , Aspergilosis/microbiología , Aspergilosis/prevención & control , Células Clonales , Citocinas/biosíntesis , Células Dendríticas/inmunología , Células Dendríticas/microbiología , Células Dendríticas/trasplante , Femenino , Vacunas Fúngicas/administración & dosificación , Humanos , Epítopos Inmunodominantes/inmunología , Enfermedades Pulmonares Fúngicas/inmunología , Enfermedades Pulmonares Fúngicas/microbiología , Enfermedades Pulmonares Fúngicas/prevención & control , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Linfocitos T Colaboradores-Inductores/metabolismo
19.
Sci Rep ; 11(1): 7220, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33790324

RESUMEN

Dandruff is a recurrent chronic scalp disorder, affecting majority of the population worldwide. Recently a metagenomic study of the Indian scalp microbiome described an imperative role of bacterial commensals in providing essential vitamins and amino acids to the scalp. Coconut oil and its formulations are commonly applied on the scalp in several parts of the world to maintain scalp health. Thus, in this study we examined the effect of topical application of coconut oil on the scalp microbiome (bacterial and fungal) at the taxonomic and functional levels and their correlation with scalp physiological parameters. A 16-weeks-long time-course study was performed including 12-weeks of treatment and 4-weeks of relapse phase on a cohort of 140 (70 healthy and 70 dandruff) Indian women, resulting in ~ 900 metagenomic samples. After the treatment phase, an increase in the abundance of Cutibacterium acnes and Malassezia globosa in dandruff scalp was observed, which were negatively correlated to dandruff parameters. At the functional level, an enrichment of healthy scalp-related bacterial pathways, such as biotin metabolism and decrease in the fungal pathogenesis pathways was observed. The study provides novel insights on the effect of coconut oil in maintaining a healthy scalp and in modulating the scalp microbiome.


Asunto(s)
Aceite de Coco/administración & dosificación , Caspa , Microbiota/efectos de los fármacos , Cuero Cabelludo/microbiología , Administración Tópica , Adulto , Caspa/tratamiento farmacológico , Caspa/microbiología , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad
20.
Microbiol Resour Announc ; 10(9)2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33664152

RESUMEN

We report the complete genome sequence of Staphylococcus epidermidis commensal strain PH1-28, isolated from the forehead of a healthy donor. The assembled 2.6-Mbp genome consisted of one chromosome and five plasmids. These data will provide valuable information and important insights into the physiology and metabolism of this skin flora microorganism.

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