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1.
PLoS One ; 12(4): e0175904, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28423056

RESUMEN

Mouse models show that experimental stress mimicking prolonged life-stress exposure enhances neurogenic inflammation, induces adaptive immunity cytokine-imbalance characterized by a shift to Type 1 T-helper cell cytokines and increases apoptosis of epithelial cells. This affects hair growth in otherwise healthy animals. In this study, we investigate whether a prolonged naturalistic life-stress exposure affects cytokine balance and hair parameters in healthy humans. 33 (18 exam, 15 comparison) female medical students with comparable sociobiological status were analyzed during a stressful final examination period, at three points in time (T) 12 weeks apart. T1 was before start of the learning period, T2 between the three-day written exam and an oral examination, and T3 after a 12 week rest and recovery from the stress of the examination period. Assessments included: self-reported distress and coping strategies (Perceived Stress Questionnaire [PSQ], Trier Inventory for the Assessment of Chronic Stress [TICS]), COPE), cytokines in supernatants of stimulated peripheral blood mononucleocytes (PBMCs), and trichogram (hair cycle and pigmentation analysis). Comparison between students participating in the final medical exam at T2 and non-exam students, revealed significantly higher stress perception in exam students. Time-wise comparison revealed that stress level, TH1/TH2 cytokine balance and hair parameters changed significantly from T1 to T2 in the exam group, but not the control. However, no group differences were found for cytokine balance or hair parameters at T2. The study concludes that in humans, naturalistic stress, as perceived during participation in a major medical exam, has the potential to shift the immune response to TH1 and transiently hamper hair growth, but these changes stay within a physiological range. Findings are instructive for patients suffering from hair loss in times of high stress. Replication in larger and more diverse sample populations is required, to assess suitability of trichogram analysis as biological outcome for stress studies.


Asunto(s)
Citocinas/biosíntesis , Cabello/inmunología , Leucocitos Mononucleares/inmunología , Estrés Psicológico/inmunología , Estudiantes de Medicina/psicología , Adolescente , Adulto , Estudios de Casos y Controles , Evaluación Educacional , Femenino , Cabello/ultraestructura , Humanos , Leucocitos Mononucleares/citología , Persona de Mediana Edad , Cultivo Primario de Células , Autoevaluación (Psicología) , Encuestas y Cuestionarios , Balance Th1 - Th2 , Factores de Tiempo
2.
Exp Dermatol ; 23(4): 247-52, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24533866

RESUMEN

We have previously shown that precursors of odorous components characteristic of axillary sweat are hardly detectable or undetectable in individuals carrying the 538G > A SNP in the ABCC11 transporter gene. However, it is unclear, whether ABCC11 is directly involved in the transport of these compounds. To approach this question, transport of peptide-conjugated potential precursors of 3-methyl-3-sulfanylhexanol (3M3SH), a key determinant of axillary malodour, was measured using membrane vesicles of Sf9 insect cells overexpressing human ABCC11. Whilst no ABCC11-mediated transport was detected for the dipeptide precursor Cys-Gly-3M3SH, the glutathione conjugate of 3M3SH (SG-3M3SH) was robustly taken up by ABCC11 at a transport rate of 0.47 pmol/mg/min. Collectively, these results illuminate SG-3M3SH as a putative precursor of 3M3SH, which then may undergo intra-vesicular maturation to generate Cys-Gly-3M3SH. Critically, the apocrine sweat gland was demonstrated to express γ-glutamyl transferase 1 (GGT1) protein, which is known to catalyse the deglutamylation of glutathionyl conjugates. Additionally, we provide evidence that recombinant and isolated hepatic human GGT1 is capable of transforming SG-3M3SH to Cys-Gly-3M3SH in vitro. To sum up, we demonstrate that the functionality of ABCC11 is likely to play an important role in the generation of axillary malodour. Furthermore, we identify GGT1 as a key enzyme involved in the biosynthesis of Cys-Gly-3M3SH.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Glándulas Apocrinas/metabolismo , Hexanoles/metabolismo , Ácidos Sulfanílicos/metabolismo , gamma-Glutamiltransferasa/metabolismo , Animales , Línea Celular , Humanos , Odorantes
3.
Skin Pharmacol Physiol ; 26(2): 108-18, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23549137

RESUMEN

BACKGROUND/AIMS: Dry, itchy and inflamed scalp conditions are common and often associated with diseases such as atopic dermatitis or psoriasis. To improve these symptoms, we investigated the efficacy of a new tonic containing the active ingredients urea, lactate, polidocanol, and Glycyrrhiza inflata root extract, containing licochalcone A. STUDY DESIGN/METHODS: 30 subjects with dry and itchy scalp conditions underwent a randomized half-head study for 4 weeks, applying the leave-on tonic three times a week on one side of the scalp. Tonic effects on skin hydration, itching, lipids, microinflammation, and substantivity of tonic compounds were determined using corneometry, middle-infrared spectroscopy, direct analysis in real-time mass spectrometry, and enzyme-linked immunosorbent assay. Volunteers performed a self-assessment; changes in scalp condition were documented by in vivo microscopy. RESULTS: After tonic treatment, scalp moisture was significantly increased, whereas scalp itching and tautness were significantly reduced. Results also demonstrated a high substantivity of urea and lactate on the scalp, an increase in triglyceride, and a decrease in free fatty acid levels. The amount of total lipids was unchanged. Analyses of scalp wash-ups verified a significant reduction in important pro-inflammatory markers. CONCLUSION: Due to the actives urea, lactate, polidocanol, and the anti-inflammatory licochalcone A, the new scalp tonic exhibited excellent performance in alleviating scalp dryness, itching, microinflammation, and in normalizing disturbances of scalp lipids.


Asunto(s)
Chalconas/administración & dosificación , Ácido Láctico/administración & dosificación , Polietilenglicoles/administración & dosificación , Prurito/tratamiento farmacológico , Dermatosis del Cuero Cabelludo/tratamiento farmacológico , Urea/administración & dosificación , Citocinas/metabolismo , Glycyrrhiza , Humanos , Metabolismo de los Lípidos , Extractos Vegetales/administración & dosificación , Raíces de Plantas , Polidocanol , Cuero Cabelludo/metabolismo
4.
J Invest Dermatol ; 130(2): 529-40, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19710689

RESUMEN

The characteristic human axillary odor is formed by bacterial action on odor precursors that originate from apocrine sweat glands. Caucasians and Africans possess a strong axillary odor ,whereas many Asians have only a faint acidic odor. In this study, we provide evidence that the gene ABCC11 (MRP8), which encodes an apical efflux pump, is crucial for the formation of the characteristic axillary odor and that a single-nucleotide polymorphism (SNP) 538G --> A, which is prominent among Asian people, leads to a nearly complete loss of the typical odor components in axillary sweat. The secretion of amino-acid conjugates of human-specific odorants is abolished in homozygotic carriers of the SNP, and steroidal odorants and their putative precursors are significantly reduced. Moreover, we show that ABCC11 is expressed and localized in apocrine sweat glands. These data point to a key function of ABCC11 in the secretion of odorants and their precursors from apocrine sweat glands. SNP 538G --> A, which also determines human earwax type, is present on an extended haplotype, which has reached >95% frequency in certain populations in recent human evolution. A strong positive selection in mate choice for low-odorant partners with a dysfunctional ABCC11 gene seems a plausible explanation for this striking frequency of a loss-of-function allele.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Alelos , Glándulas Apocrinas/metabolismo , Axila/fisiología , Odorantes , Adulto , Aminoácidos/química , Femenino , Regulación de la Expresión Génica , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Sudor
5.
J Dtsch Dermatol Ges ; 2(7): 580-7, 2004 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-16281620

RESUMEN

The flavonoid alpha-glucosylrutin (AGR) is a potent antioxidant with a high epidermal bioavailability. This makes this substance particularly suitable for various dermato-cosmetic applications. Flavonoids are phytamines with a common chemical structure and a broad range of activities, the most prominent being their radical scavenging ability. Reactive oxygen species (ROS) damage cells by different mechanisms. Direct cytotoxic effects include destruction of the cell membrane by causing radical chain reactions or induction of mutagenic changes in the nuclear and mitochondrial DNA. Indirect changes involve modification of intracellular signal transduction pathways that regulate inflammatory or proliferative activities. The excellent antioxidant efficacy of AGR has been shown in various experimental studies, both in vitro and in vivo. Subsequent clinical studies have demonstrated that AGR is also effective in the prevention of dermatologic diseases in which oxidative stress is of pathogenetic relevance, e.g. in polymorphous light eruption (PLE). Other promising dermato-cosmetic areas for AGR application are aging of the skin, especially photoaging. All in vivo evaluations indicate that AGR in the applied concentrations is a very well-tolerated ingredient for medical skin care preparations.


Asunto(s)
Flavonoides/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Rutina/análogos & derivados , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/metabolismo , Piel/efectos de los fármacos , Piel/metabolismo , Animales , Antioxidantes/administración & dosificación , Humanos , Rutina/administración & dosificación , Resultado del Tratamiento , Trisacáridos
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