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1.
Eur J Med Res ; 27(1): 255, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36411478

RESUMEN

BACKGROUND: The presentation of peptides and the subsequent immune response depend on the MHC characteristics and influence the specificity of the immune response. Several studies have found an association between HLA variants and differential COVID-19 outcomes and have shown that HLA genotypes are associated with differential immune responses against SARS-CoV-2, particularly in severely ill patients. Information, whether HLA haplotypes are associated with the severity or length of the disease in moderately diseased individuals is absent. METHODS: Next-generation sequencing-based HLA typing was performed in 303 female and 231 male non-hospitalized North Rhine Westphalian patients infected with SARS-CoV2 during the first and second wave. For HLA-Class I, we obtained results from 528 patients, and for HLA-Class II from 531. In those patients, who became ill between March 2020 and January 2021, the 22 most common HLA-Class I (HLA-A, -B, -C) or HLA-Class II (HLA -DRB1/3/4, -DQA1, -DQB1) haplotypes were determined. The identified HLA haplotypes as well as the presence of a CCR5Δ32 mutation and number of O and A blood group alleles were associated to disease severity and duration of the disease. RESULTS: The influence of the HLA haplotypes on disease severity and duration was more pronounced than the influence of age, sex, or ABO blood group. These associations were sex dependent. The presence of mutated CCR5 resulted in a longer recovery period in males. CONCLUSION: The existence of certain HLA haplotypes is associated with more severe disease.


Asunto(s)
COVID-19 , Humanos , Masculino , Femenino , COVID-19/genética , Antígenos HLA-DQ/genética , Pronóstico , ARN Viral , SARS-CoV-2 , Cadenas HLA-DRB1
2.
Eur J Med Res ; 26(1): 107, 2021 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-34530915

RESUMEN

BACKGROUND: COVID-19, the pandemic disease caused by infection with SARS-CoV-2, may take highly variable clinical courses, ranging from symptom-free and pauci-symptomatic to fatal disease. The goal of the current study was to assess the association of COVID-19 clinical courses controlled by patients' adaptive immune responses without progression to severe disease with patients' Human Leukocyte Antigen (HLA) genetics, AB0 blood group antigens, and the presence or absence of near-loss-of-function delta 32 deletion mutant of the C-C chemokine receptor type 5 (CCR5). PATIENT AND METHODS: An exploratory observational study including 157 adult COVID-19 convalescent patients was performed with a median follow-up of 250 days. The impact of different HLA genotypes, AB0 blood group antigens, and the CCR5 mutant CD195 were investigated for their role in the clinical course of COVID-19. In addition, this study addressed levels of severity and morbidity of COVID-19. The association of the immunogenetic background parameters were further related to patients' humoral antiviral immune response patterns by longitudinal observation. RESULTS: Univariate HLA analyses identified putatively protective HLA alleles (HLA class II DRB1*01:01 and HLA class I B*35:01, with a trend for DRB1*03:01). They were associated with reduced durations of disease instead decreased (rather than increased) total anti-S IgG levels. They had a higher virus neutralizing capacity compared to non-carriers. Conversely, analyses also identified HLA alleles (HLA class II DQB1*03:02 und HLA class I B*15:01) not associated with such benefit in the patient cohort of this study. Hierarchical testing by Cox regression analyses confirmed the significance of the protective effect of the HLA alleles identified (when assessed in composite) in terms of disease duration, whereas AB0 blood group antigen heterozygosity was found to be significantly associated with disease severity (rather than duration) in our cohort. A suggestive association of a heterozygous CCR5 delta 32 mutation status with prolonged disease duration was implied by univariate analyses but could not be confirmed by hierarchical multivariate testing. CONCLUSION: The current study shows that the presence of HLA class II DRB1*01:01 and HLA class I B*35:01 is of even stronger association with reduced disease duration in mild and moderate COVID-19 than age or any other potential risk factor assessed. Prospective studies in larger patient populations also including novel SARS-CoV-2 variants will be required to assess the impact of HLA genetics on the capacity of mounting protective vaccination responses in the future.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/genética , COVID-19/etiología , Antígenos HLA/genética , Receptores CCR5/genética , Adulto , Anciano , COVID-19/epidemiología , COVID-19/genética , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Cadenas HLA-DRB1/genética , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Morbilidad , Mutación , Índice de Severidad de la Enfermedad
3.
Trials ; 22(1): 343, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-34001215

RESUMEN

OBJECTIVES: Currently, there are no approved treatments for early disease stages of COVID-19 and few strategies to prevent disease progression after infection with SARS-CoV-2. The objective of this study is to evaluate the safety and efficacy of convalescent plasma (CP) or camostat mesylate administered within 72 h of diagnosis of SARS-CoV-2 infection in adult individuals with pre-existing risk factors at higher risk of getting seriously ill with COVID-19. Camostat mesylate acts as an inhibitor of the host cell serine protease TMPRSS2 and prevents the virus from entering the cell. CP represents another antiviral strategy in terms of passive immunization. The working hypothesis to be tested in the RES-Q-HR study is that the early use of CP or camostat mesylate reduces the likelihood of disease progression to (modified) WHO stages 4b-8 in SARS-CoV-2-positive adult patients at high risk of moderate or severe COVID-19 progression. TRIAL DESIGN: This study is a 4-arm (parallel group), multicenter, randomized (2:2:1:1 ratio), partly double-blind, controlled trial to evaluate the safety and efficacy of convalescent plasma (CP) or camostat mesylate with control or placebo in adult patients diagnosed with SARS-CoV-2 infection and high risk for progression to moderate/severe COVID-19. Superiority of the intervention arms will be tested. PARTICIPANTS: The trial is conducted at 10-15 tertiary care centers in Germany. Individuals aged 18 years or above with ability to provide written informed consent with SARS-CoV-2 infection, confirmed by PCR within 3 days or less before enrolment and the presence of at least one SARS-CoV-2 symptom (such as fever, cough, shortness of breath, sore throat, headache, fatigue, smell/and or taste disorder, diarrhea, abdominal symptoms, exanthema) and symptom duration of not more than 3 days. Further inclusion criteria comprise: Presence of at least one of the following criteria indicating increased risk for severe COVID-19: Age > 75 years Chronic obstructive pulmonary disease (COPD) and/or pulmonary fibrosis BMI > 40 kg/m2 Age > 65 years with at least one other risk factor (BMI > 35 kg/m2, coronary artery disease (CAD), chronic kidney disease (CKD) with GFR < 60 ml/min but ≥ 30 ml/min, diabetes mellitus, active tumor disease) BMI > 35 kg/m2 with at least one other risk factor (CAD, CKD with GFR < 60 ml/min but ≥ 30 ml/min, diabetes mellitus, active tumor disease) Exclusion criteria: 1. Age < 18 years 2. Unable to give informed consent 3. Pregnant women or breastfeeding mothers 4. Previous transfusion reaction or other contraindication to a plasma transfusion 5. Known hypersensitivity to camostat mesylate and/or severe pancreatitis 6. Volume stress due to CP administration would be intolerable 7. Known IgA deficiency 8. Life expectancy < 6 months 9. Duration SARS-CoV-2 typical symptoms > 3 days 10. SARS-CoV-2 PCR detection older than 3 days 11. SARS-CoV-2 associated clinical condition ≥ WHO stage 3 (patients hospitalized for other reasons than COVID-19 may be included if they fulfill all inclusion and none of the exclusion criteria) 12. Previously or currently hospitalized due to SARS-CoV-2 13. Previous antiviral therapy for SARS-CoV-2 14. ALT or AST > 5 x ULN at screening 15. Liver cirrhosis > Child A (patients with Child B/C cirrhosis are excluded from the trial) 16. Chronic kidney disease with GFR < 30 ml/min 17. Concurrent or planned anticancer treatment during trial period 18. Accommodation in an institution due to legal orders (§40(4) AMG). 19. Any psycho-social condition hampering compliance with the study protocol. 20. Evidence of current drug or alcohol abuse 21. Use of other investigational treatment within 5 half-lives of enrolment is prohibited 22. Previous use of convalescent plasma for COVID-19 23. Concomitant proven influenza A infection 24. Patients with organ or bone marrow transplant in the three months prior to screening visit INTERVENTION AND COMPARATOR: Participants will be randomized to the following 4 groups: 1) Convalescent plasma (CP), 2 units at screening/baseline visit (day 0) or day 1; CP is defined by the presence of neutralizing anti-SARS-CoV-2 antibodies with titers ≥ 1:160; individuals with body weight ≥ 150 kg will receive a third unit of plasma on day 3 2) Camostat mesylate (200 mg per capsule, one capsule taken each in the morning, afternoon and evening on days 1-7) 3) Standard of care (SOC, control for CP) 4) Placebo (identical in appearance to camostat mesylate capsules, one capsule taken each morning, afternoon and evening on days 1-7; for camostat mesylate control group) Participants will be monitored after screening/baseline on day 3, day 5, day 8, and day 14. On day 28 and day 56, telephone visits and on day 90, another outpatient visit are scheduled. Adverse events and serious adverse events will be monitored and reported until the end of the study. An independent data safety monitoring committee will review trial progression and safety. MAIN OUTCOMES: The primary endpoint of the study is the cumulative number of individuals who progress to or beyond category 4b on the modified WHO COVID-19 ordinal scale (defined as hospitalization with COVID-19 pneumonia and additional oxygen demand via nasal cannula or mask) within 28 days after randomization. RANDOMIZATION: Participants will be randomized using the Alea-Tool ( aleaclinical.com ) in a 2:2:1:1 ratio to the treatment arms (1) CP, (2) camostat mesylate, (3) standard of care (SoC), and (4) placebo matching camostat mesylate. Randomization will be stratified by study center. BLINDING (MASKING): The camostat mesylate treatment arm and the respective placebo will be blinded for participants, caregivers, and those assessing outcomes. The treatment arms convalescent plasma and standard of care will not be blinded and thus are open-labeled, unblinded. NUMBERS TO BE RANDOMIZED (SAMPLE SIZE): Overall, n = 994 participants will be randomized to the following groups: n = 331 to convalescent plasma (CP), n = 331 to camostat mesylate, n = 166 to standard of care (SoC), and n = 166 to placebo matching camostat mesylate. TRIAL STATUS: The RES-Q-HR protocol (V04F) was approved on the 18 December 2020 by the local ethics committee and by the regulatory institutions PEI/BfARM on the 2 December 2020. The trial was opened for recruitment on 26 December 2020; the first patient was enrolled on 7 January 2021 and randomized on 8 January 2021. Recruitment shall be completed by June 2021. The current protocol version RES-Q HR V05F is from 4 January 2021, which was approved on the 18 January 2021. TRIAL REGISTRATION: EudraCT Number 2020-004695-18 . Registered on September 29, 2020. ClinicalTrial.gov NCT04681430 . Registered on December 23, 2020, prior to the start of the enrollment (which was opened on December 26, 2020). FULL PROTOCOL: The full protocol (V05F) is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).


Asunto(s)
COVID-19 , Preparaciones Farmacéuticas , Complicaciones Infecciosas del Embarazo , Adolescente , Adulto , Anciano , Transfusión de Componentes Sanguíneos , COVID-19/terapia , Niño , Ésteres , Femenino , Alemania , Guanidinas , Humanos , Inmunización Pasiva , Mesilatos , Estudios Multicéntricos como Asunto , Plasma , Reacción en Cadena de la Polimerasa , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , SARS-CoV-2 , Resultado del Tratamiento , Sueroterapia para COVID-19
4.
Microbiology (Reading) ; 157(Pt 10): 2871-2879, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21798983

RESUMEN

Transcription of rRNAs in Escherichia coli is directed from seven redundant rRNA operons, which are mainly regulated by their P1 promoters. Here we demonstrate by in vivo measurements that the amounts of individual rRNAs transcribed from the different operons under normal growth vary noticeably although the structures of all the P1 promoters are very similar. Moreover, we show that starvation for amino acids does not affect the seven P1 promoters in the same way. Notably, reduction of transcription from rrnD P1 was significantly lower compared to the other P1 promoters. The presence of DksA was shown to be crucial for the ppGpp-dependent downregulation of all P1 promoters. Because rrnD P1 is the only rrn promoter starting with GTP instead of ATP, we performed studies with a mutant rrnD promoter, where the initiating G+1 is replaced by A+1. These analyses demonstrated that the ppGpp sensitivity of rrn P1 promoters depends on the nature and concentration of initiating nucleoside triphosphates (iNTPs). Our results support the notion that the seven rRNA operons are differentially regulated and underline the importance of a concerted activity between ppGpp, DksA and an adequate concentration of the respective iNTP.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica , Nucleótidos de Guanina/metabolismo , Nucleótidos/metabolismo , Regiones Promotoras Genéticas , ARN Bacteriano/genética , Secuencia de Bases , Regulación hacia Abajo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Datos de Secuencia Molecular , ARN Bacteriano/metabolismo , Operón de ARNr
5.
J Invest Dermatol ; 130(6): 1524-36, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20130591

RESUMEN

Infrared A (IRA) radiation (760-1440 nm) is a major component of solar radiation and, similar to UVR, causes photoaging of human skin by increasing the expression of matrix metalloproteinase-1 in human skin fibroblasts. In this study, we assessed the IRA-induced transcriptome in primary human skin fibroblasts. Microarray analysis revealed 599 IRA-regulated transcripts. The IRA-induced transcriptome differed from changes known to be induced by UV. IRA-responsive genes include the categories extracellular matrix, calcium homeostasis, stress signaling, and apoptosis. Selected results were confirmed by real-time PCR experiments analyzing 13 genes representing these four categories. By means of chemical inhibitors of known signaling pathways, we showed that ERK1/2, the p38-, JNK-, PI3K/AKT-, STAT3-, and IL-6 as well as the calcium-mediated signaling pathways, are functionally involved in the IRA gene response and that a major part of it is triggered by mitochondrial and, to a lesser extent, non-mitochondrial production of reactive oxygen species. Our results identify IRA as an environmental factor with relevance for skin homeostasis and photoaging.


Asunto(s)
Fibroblastos/efectos de la radiación , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de la radiación , Rayos Infrarrojos , Piel/efectos de la radiación , Apoptosis/fisiología , Apoptosis/efectos de la radiación , Células Cultivadas , Matriz Extracelular/metabolismo , Matriz Extracelular/efectos de la radiación , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Homeostasis/fisiología , Homeostasis/efectos de la radiación , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Masculino , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Piel/citología , Piel/metabolismo , Estrés Fisiológico/fisiología , Estrés Fisiológico/efectos de la radiación , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
6.
Exp Gerontol ; 43(7): 633-637, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18524517

RESUMEN

Exposure of human skin to solar radiation, which includes ultraviolet (UV) radiation (UVA and UVB) visible light and infrared radiation, induces skin aging. The effects of light have been attributed to irradiation-induced reactive oxygen species (ROS) formation, but the specific signaling pathways are not well understood. Detrimental effects of solar radiation are dermal diseases and photoaging. Exposure of cultured human dermal fibroblasts to UVA, UVB or IRA increased ROS formation in vitro. One important redox regulator is the oxidoreductase thioredoxin-1 (Trx). Trx is ubiquitously expressed and has anti-oxidative and anti-apoptotic properties. Besides its function to reduce H(2)O(2), Trx binds to and regulates transcription factors. The aim of this study was to investigate whether Trx influences the regulation of MMP-1 and collagen Ialpha1 by UVA, UVB and IRA. We irradiated human dermal fibroblasts with UVA, UVB and IRA. UVA, UVB and IRA upregulated MMP-1 expression. Trx inhibited UVA-induced MMP-1 upregulation in a NFkappaB dependent manner. UVA, UVB and IRA reduced collagen Ialpha1 expression. Incubation with Trx inhibited the effects of UVB and IRA on collagen Ialpha1 expression. In conclusion, MMP-1 and collagen Ialpha1, which play important roles in aging processes, seems to be regulated by different transcriptional mechanisms and Trx can only influence distinct signaling pathways induced by UVA, UVB and probably IRA. Thus, Trx may serve as an important contributor to an "anti-aging therapeutic cocktail".


Asunto(s)
Fibroblastos/efectos de la radiación , Rayos Infrarrojos , Piel/efectos de la radiación , Tiorredoxinas/farmacología , Rayos Ultravioleta , Células Cultivadas , Colágeno Tipo I/biosíntesis , Colágeno Tipo I/genética , Cadena alfa 1 del Colágeno Tipo I , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/efectos de la radiación , Humanos , Metaloproteinasa 1 de la Matriz/biosíntesis , Metaloproteinasa 1 de la Matriz/genética , FN-kappa B/antagonistas & inhibidores , FN-kappa B/fisiología , Reacción en Cadena de la Polimerasa/métodos , ARN Mensajero/genética , Piel/efectos de los fármacos , Piel/metabolismo , Envejecimiento de la Piel/efectos de la radiación , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/efectos de la radiación
7.
Free Radic Biol Med ; 45(1): 86-91, 2008 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-18454944

RESUMEN

Changes of the redox balance in cells alter the availability of intracellular free Zn(2+). Here, cells were exposed to ultraviolet (UV)-A, UV-B, or infrared (IR)-A light irradiation, and the intracellular free zinc pool was monitored. Under sublethal conditions only UV-A irradiation resulted in a transient cytoplasmic and nuclear increase of intracellular free Zn(2+). Likewise, tert-butyl hydroperoxide and singlet oxygen, but not H(2)O(2) or intracellular generation of O(2)(*-) by redox cyclers, mimicked the effects of UV-A irradiation, while disulfide stress by diamide only led to a transient cytoplasmic zinc release. These results show that only certain types of subtoxic cellular stress massively disturb the zinc homeostasis in cells.


Asunto(s)
Homeostasis/efectos de la radiación , Rayos Ultravioleta , Zinc/metabolismo , Animales , Línea Celular , Diamida/farmacología , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Homeostasis/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Ratones , Oxidación-Reducción , Quinonas/metabolismo , Oxígeno Singlete/metabolismo
8.
Free Radic Biol Med ; 43(1): 128-35, 2007 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-17561101

RESUMEN

Infrared A radiation (IRA) is a major component of sunlight. Similar to ultraviolet (UV) B and UVA, IRA induces gene transcription. In contrast to the UV response very little is known about the IRA response. In the present study, IRA-induced expression of matrix metalloproteinase-1 (MMP-1) was found to be mediated by the formation of intracellular reactive oxygen species (ROS). Staining of IRA-irradiated cells with MitoSox revealed an increase in mitochondrial superoxide anion production and treatment of fibroblasts with the mitochondrial targeted antioxidant MitoQ completely abrogated the IRA, but not the UVB or UVA1, response. ROS relevant for IRA-induced signaling originated from the mt electron transport chain, because (i) chemical inhibition of the electron transport chain prevented IRA, but not UVB or UVA1, radiation-induced MMP-1 expression, (ii) rho0 fibroblasts specifically failed to increase MMP-1 expression in response to IRA, and (iii) peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) overexpressing fibroblasts with increased electron transport chain content were hypersensitive to IRA radiation-induced gene expression. Thus, IRA, in contrast to UV, elicits a retrograde signaling response in human skin.


Asunto(s)
Rayos Infrarrojos , Mitocondrias/metabolismo , Piel/efectos de la radiación , Superóxidos/metabolismo , Antioxidantes/farmacología , Células Cultivadas , Transporte de Electrón , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Humanos , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Compuestos Organofosforados/farmacología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Piel/metabolismo , Piel/ultraestructura , Factores de Transcripción/metabolismo , Ubiquinona/análogos & derivados , Ubiquinona/farmacología , Rayos Ultravioleta
9.
Biol Chem ; 388(6): 583-92, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17552905

RESUMEN

Environmental factors, including sunlight, are able to induce severe oxidative protein damage. The modified proteins are either repaired, degraded or escape from degradation and aggregate. In the present study we tested the effect of different sunlight components such as UV-A, UV-B, and infrared radiation on protein oxidation in vitro. We chose glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a model enzyme and analyzed the irradiation-induced enzyme activity loss, fragmentation and aggregation, and quantified various oxidative amino acid modifications. Since gamma-irradiation was used in numerous studies before, we used it for comparative purposes. Infrared radiation was unable to damage GAPDH in the dose range tested (0-1000 J/cm(2)). UV-A led to a decrease in free thiol content, which was connected with a loss in enzyme activity, while only at very high doses could moderate protein aggregation and fragmentation be observed. UV-B (0-2 J/cm(2)) and gamma-irradiation (0-500 Gy) led to a dose-dependent increase in protein modification. Interestingly, UV-B acted on specific amino acids, such as arginine, proline, and tyrosine, whereas gamma-irradiation acted more randomly. The possibility of using the amino acid oxidation pattern as a biomarker of the source of damage is discussed.


Asunto(s)
Rayos gamma , Gliceraldehído-3-Fosfato Deshidrogenasas/efectos de la radiación , Rayos Infrarrojos , Rayos Ultravioleta , Aminoácidos/química , Gliceraldehído-3-Fosfato Deshidrogenasas/química , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , NAD/metabolismo , Oxidación-Reducción , Carbonilación Proteica , Compuestos de Sulfhidrilo/química
10.
Proc Natl Acad Sci U S A ; 104(21): 8851-6, 2007 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-17502624

RESUMEN

UVB radiation-induced signaling in mammalian cells involves two major pathways: one that is initiated through the generation of DNA photoproducts in the nucleus and a second one that occurs independently of DNA damage and is characterized by cell surface receptor activation. The chromophore for the latter one has been unknown. Here, we report that the UVB response involves tryptophan as a chromophore. We show that through the intracellular generation of photoproducts, such as the arylhydrocarbon receptor (AhR) ligand 6-formylindolo[3,2-b]carbazole, signaling events are initiated, which are transferred to the nucleus and the cell membrane via activation of the cytoplasmatic AhR. Specifically, AhR activation by UVB leads to (i) transcriptional induction of cytochrome P450 1A1 and (ii) EGF receptor internalization with activation of the EGF receptor downstream target ERK1/2 and subsequent induction of cyclooxygenase-2. The role of the AhR in the UVB stress response was confirmed in vivo by studies employing AhR KO mice.


Asunto(s)
Citoplasma/metabolismo , Citoplasma/efectos de la radiación , Receptores de Hidrocarburo de Aril/metabolismo , Rayos Ultravioleta , Transporte Activo de Núcleo Celular , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Carbazoles/química , Carbazoles/metabolismo , Línea Celular , Núcleo Celular/metabolismo , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Receptores ErbB/metabolismo , Regulación de la Expresión Génica , Humanos , Indoles/química , Indoles/metabolismo , Ratones , Ratones Noqueados , Estructura Molecular , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , Receptores de Hidrocarburo de Aril/deficiencia , Receptores de Hidrocarburo de Aril/genética , Transducción de Señal/efectos de la radiación , Transcripción Genética/genética , Triptófano/metabolismo
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