RESUMO
Early embryos of rodent species and rabbits but also farm animals such as pigs, horses and cattle produce estrogens, which are considered important regulators of the implantation process. In cattle, the exact stage at which embryonic estrogen synthesis commences is yet unknown. However, this information is regarded as important to consider a possible role of embryonic estrogens in preimplantation development. Therefore, in this study, we first used quantitative reverse transcription PCR to examine the mRNA expression of the enzymes required for the conversion of cholesterol into free and sulfonated estrogens (CYP11A1, CYP17A1, HSD3B, CYP19A1, and SULT1E1), the cholesterol carrier protein STAR, and the estrogen receptors ESR1 and ESR2 in in vitro produced morulae and unhatched blastocysts (d 6-9). Only in the blastocysts, were the mRNAs of the entire estrogen biosynthesis chain and of both estrogen receptors clearly present, whereas mRNA specific to ESRs was already detectable in the morulae. We also examined the expression of the corresponding enzymes in blastocysts at the protein level. None of the enzymes were detectable by capillary-based western analysis. Immunofluorescence methods were established for the detection of CYP17A1, CYP19A1, and SULT1E1. CYP17A1 was observed in the inner cell mass and trophectoderm, whereas CYP19A1 and SULT1E1 were present only in trophectoderm. An attempt to detect estrogen sulfotransferase activity was unsuccessful. Despite clear evidence that some elements of the estrogen biosynthetic pathway are also present at the protein level, it remains to be clarified whether the enzyme cascade underlying estrogen production is already functional in unhatched blastocysts.
Assuntos
Vias Biossintéticas , Receptores de Estrogênio , Bovinos/genética , Animais , Suínos , Coelhos , Cavalos/genética , Blastocisto/fisiologia , Estrogênios/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Esteroides/metabolismoRESUMO
OBJECTIVE: Osteoarthritis (OA) is characterized by the gradual loss of cartilage. Sprifermin, a recombinant FGF18, is being developed as a cartilage anabolic drug. PRO-C2 is a serum marker of type II collagen formation and low levels have been shown to be prognostic of radiographic progression. The aim of the study was to investigate whether the patient groups with either high or low PRO-C2 levels responded differently to sprifermin. DESIGN: PRO-C2 was measured in synovial fluid (SF) (n = 59) and serum samples (n = 225) from participants of the FORWARD study, a 2-year phase IIb clinical trial testing the efficacy of intra-articular (IA) sprifermin over placebo. The difference between sprifermin and placebo in respect to in change cartilage thickness (measured by quantitative (q) MRI) was analyzed in groups with either high or low (3rd vs 1st-2nd tertiles) baseline serum PRO-C2 levels. RESULTS: SF levels of PRO-C2 increased over time in response to sprifermin, but not to placebo. In the placebo arm, significantly (p = 0.005) more cartilage was lost in the low vs high PRO-C2 group over the 2-year period. The contrast between sprifermin and placebo was significant (p < 0.001), ranging from 0.104 mm at week 26 to 0.229 mm at week 104 in the low PRO-C2 group. This result was not significant in the high PRO-C2 group ranging from -0.034 to 0.142. CONCLUSIONS: Patients with low serum PRO-C2 levels lost more cartilage thickness over time and grew more cartilage in response to sprifermin vs a placebo when compared to patients with high PRO-C2 levels.
Assuntos
Colágeno Tipo II/análise , Fatores de Crescimento de Fibroblastos/uso terapêutico , Osteoartrite/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Biomarcadores/sangue , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Colágeno Tipo II/sangue , Método Duplo-Cego , Feminino , Fatores de Crescimento de Fibroblastos/administração & dosagem , Fatores de Crescimento de Fibroblastos/farmacologia , Humanos , Injeções Intra-Articulares , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Líquido Sinovial/química , Resultado do TratamentoRESUMO
Sprifermin, recombinant human fibroblast growth factor 18 (rhFGF18), induces cartilage regeneration in knees of patients with osteoarthritis (OA). We hypothesized that a temporal multiphasic process of extracellular matrix (ECM) degradation and formation underlie this effect. We aimed to characterize the temporal ECM remodeling of human knee OA articular cartilage in response to sprifermin treatment. Articular cartilage explants from patients with knee OA (npatients = 14) were cultured for 70 days, with permanent exposure to sprifermin (900, 450, 225 ng/mL), FGF18 (450 ng/mL), insulin-like growth factor-1 (100 ng/mL, positive control) or vehicle (nreplicates/treatment/patient = 2). Metabolic activity (AlamarBlue) and biomarkers of type IIB collagen (PIIBNP) formation (Pro-C2 enzyme-linked immunosorbent assay [ELISA]) and aggrecanase-mediated aggrecan neo-epitope NITEGE (AGNx1 ELISA) were quantified once a week. At end of culture (day 70), gene expression (quantitative reverse transcription polymerase chain reaction) and proteoglycan content (Safranin O/Fast green staining) were quantified. The cartilage had continuously increased metabolic activity, when treated with sprifermin/FGF18 compared to vehicle. During days 7-28 PIIBNP was decreased and NITEGE was increased, and during days 35-70 PIIBNP was increased. At end of culture, the cartilage had sustained proteoglycan content and relative expression of ACAN < COL2A1 < SOX9 < COL1A1, indicating that functional chondrocytes remained in the explants. Sprifermin induces a temporal biphasic cartilage remodeling in human knee OA articular cartilage explants, with early-phase increased aggrecanase activity and late-phase increased type II collagen formation.
Assuntos
Cartilagem Articular/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Fatores de Crescimento de Fibroblastos/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Colágeno Tipo II/análise , Colágeno Tipo II/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Humanos , Masculino , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Proteoglicanas/análise , Proteoglicanas/metabolismoRESUMO
OBJECTIVE: Links between pain and joint degradation are poorly understood. We investigated the role of activation of Toll-like receptors (TLR) by cartilage metabolites in initiating and maintaining the inflammatory loop in OA causing joint destruction. METHODS: Synovial membrane explants (SMEs) were prepared from OA patients' synovial biopsies. SMEs were cultured for 10 days under following conditions: culture medium alone, OSM + TNFα, TLR2 agonist - Pam2CSK4, Pam3CSK4 or synthetic aggrecan 32-mer, TLR4 agonist - Lipid A. Release of pro-inflammatory and degradation biomarkers (acMMP3 and C3M) were measured by ELISA in conditioned media along with IL-6. Additionally, human cartilage was digested with ADAMTS-5, with or without the ADAMTS-5 inhibiting nanobody - M6495. Digested cartilage solution (DCS) and synthetic 32-mer were tested for TLR activation in SEAP based TLR reporter assay. RESULTS: Western blotting confirmed TLR2 and TLR4 in untreated OA synovial biopsies. TLR agonists showed an increase in release of biomarkers - acMMP3 and C3M in SME. Synthetic 32-mer showed no activation in the TLR reporter assay. ADAMTS-5 degraded cartilage fragments activated TLR2 in vitro. Adding M6495 - an anti-ADAMTS-5 inhibiting nanobody®, blocked ADAMTS-5-mediated DCS TLR2 activation. CONCLUSION: TLR2 is expressed in synovium of OA patients and their activation by synthetic ligands causes increased tissue turnover. ADAMTS-5-mediated cartilage degradation leads to release of aggrecan fragments which activates the TLR2 receptor in vitro. M6495 suppressed cartilage degradation by ADAMTS-5, limiting the activation of TLR2. In conclusion, pain and joint destruction may be linked to generation of ADAMTS-5 cartilage metabolites.
Assuntos
Proteína ADAMTS5/metabolismo , Cartilagem Articular/metabolismo , Inflamação/metabolismo , Membrana Sinovial/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteína ADAMTS5/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Agrecanas/metabolismo , Western Blotting , Cartilagem Articular/efeitos dos fármacos , Feminino , Humanos , Técnicas In Vitro , Interleucina-6/metabolismo , Lipídeo A/farmacologia , Lipopeptídeos/farmacologia , Masculino , Metaloproteinase 3 da Matriz/efeitos dos fármacos , Metaloproteinase 3 da Matriz/metabolismo , Pessoa de Meia-Idade , Oligopeptídeos/farmacologia , Anticorpos de Domínio Único/farmacologia , Membrana Sinovial/efeitos dos fármacos , Receptor 2 Toll-Like/agonistas , Receptor 4 Toll-Like/agonistas , Receptor Toll-Like 9/agonistas , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Although successful in the structural determination of ordered biomolecules, the spectroscopic investigation of oligopeptides in solution is hindered by their complex and rapidly changing conformational ensemble. The measured circular dichroism (CD) spectrum of an oligopeptide is an ensemble average over all microstates, severely limiting its interpretation, in contrast to ordered biomolecules. Spectral deconvolution methods to estimate the secondary structure contributions in the ensemble are still mostly based on databases of larger ordered proteins. Here, we establish how the interpretation of CD spectra of oligopeptides can be enhanced by the ability to compute the same observable from a set of atomic coordinates. Focusing on two representative oligopeptides featuring a known propensity toward an α-helical and ß-hairpin motif, respectively, we compare and cross-validate the structural information coming from deconvolution of the experimental CD spectra, sequence-based de novo structure prediction, and molecular dynamics simulations based on enhanced sampling methods. We find that small conformational variations can give rise to significant changes in the CD signals. While for the simpler conformational landscape of the α-helical peptide de novo structure prediction can already give reasonable agreement with the experiment, an extended ensemble of conformers needs to be considered for the ß-hairpin sequence.
Assuntos
Oligopeptídeos/química , Sequência de Aminoácidos , Dicroísmo Circular , Análise por Conglomerados , Simulação de Dinâmica Molecular , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha betaRESUMO
Osteoarthritis (OA) is the biggest unmet medical need among the many musculoskeletal conditions and the most common form of arthritis. It is a major cause of disability and impaired quality of life in the elderly. We review several ambitious but failed attempts to develop joint structure-modifying treatments for OA. Insights gleaned from these attempts suggest that these failures arose from unrealistic hypotheses, sub-optimal selection of patient populations or drug dose, and/or inadequate sensitivity of the trial endpoints. The long list of failures has prompted a paradigm shift in OA drug development with redirection of attention to: (1) consideration of the benefits of localized vs systemic pharmacological agents, as indicated by the increasing number of intra-articularly administered compounds entering clinical development; (2) recognition of OA as a complex disease with multiple phenotypes, that may each require somewhat different approaches for optimizing treatment; and (3) trial enhancements based on guidance regarding biomarkers provided by regulatory agencies, such as the Food and Drug Administration (FDA), that could be harnessed to help turn failures into successes.
Assuntos
Osteoartrite do Joelho , Humanos , Joelho , Articulação do Joelho , Osteoartrite do Quadril , Qualidade de VidaRESUMO
Transdermal delivery systems (TDS) consisting of mixtures of adhesives also named multiple polymer adhesive systems are rarely found in the market and research has only been performed on a few of them. Following the principles of ICH Q8, a Design of Experiments (DOE) approach was selected for the formulation development. For evaluation of the statistical method of "mixture design", blends of silicon adhesive, acrylic adhesive, oleyl alcohol as a surfactant and ibuprofen as a model drug were considered to be combined at different concentrations. A randomized design of 16 runs with five replicates and five runs to estimate the lack of fit (LOF) was generated. Samples were tested for adhesion properties, stability of the wet mixes, solubility of the API in the matrix and appearance of the matrix. After performing an ANOVA with the results, response surfaces of tack, shear adhesion, extent of creaming, crystallization behavior, droplet size and droplet size range were derived as contour plots. It could be shown that crystal growth of ibuprofen correlates well with droplet size and droplet size range, where lowest values for crystallization were found with mixtures containing small droplets. However, it was observed that oleyl alcohol showed no positive effect on the miscibility of the polymers and no improvement of the solubility of ibuprofen in the mixtures. With a reasonable number of experiments, the development of a design space for a TDS via mixture design gave valuable information on the product as well as on the interactions of the components.
Assuntos
Sistemas de Liberação de Medicamentos , Ibuprofeno/administração & dosagem , Polímeros/química , Tensoativos/química , Adesividade , Adesivos/química , Administração Cutânea , Química Farmacêutica/métodos , Cristalização , Álcoois Graxos/química , Ibuprofeno/química , Silício/química , Solubilidade , Adesivo TransdérmicoRESUMO
AIM OF THE STUDY: Patient satisfaction is an essential quality and outcome criteria for patient-centered treatment of chronic diseases. For successful implementation of integrated patient-centered care it is important to take the needs and expectations of the patients into consideration in the treatment process and to involve them in decision-making (external participation), as well as establishing patient-centered collaboration within the team and organization (internal participation). This study examines in what respect patient satisfaction can be predicted through parameters that focus on the personal needs of the individual or internal and external participation. METHODS: To this end we used a multicenter cross-sectional study to collect evaluations from N=329 patients with different chronic diseases in 11 rehabilitation clinics. Patient satisfaction (ZUF-8) served as the criterion, and the predictors were external participation (PEF-FB-9), satisfaction with decision-making (Man-Son-Hing Scale) and internal participation (Internal Participation Scale), socio-demographic factors and rehabilitation status (IRES-24). The data were analyzed statistically using multiple linear regression. RESULTS: A high degree of variance of patient satisfaction could be explained by the parameters applied (Goodness-of-fit: R²corrected=47.3%). The strongest predictors of satisfaction were internal participation (Beta=0.44, p<0.001) and satisfaction with the decision-making (Beta=0.36, p<0.001). CONCLUSION: The study provides initial indications of the positive effects of internal and external participation. Further studies are necessary to substantiate the connection between internal and external participation and patient satisfaction.
Assuntos
Doença Crônica/epidemiologia , Doença Crônica/reabilitação , Tomada de Decisões , Participação do Paciente/psicologia , Participação do Paciente/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Assistência Centrada no Paciente/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Doença Crônica/psicologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Distribuição por Sexo , Fatores Socioeconômicos , Resultado do Tratamento , Adulto JovemRESUMO
In transdermal patches, an unpredictable alteration of the mechanical behavior of the pressure sensitive adhesive (PSA) can occur if a drug is added. In the present study, the suitability of Dynamic Mechanical Analysis (DMA)/Dynamic Mechanical Thermal Analysis (DMTA) as methodologies to detect the change in adhesion properties caused by the addition of an API was examined. With DMA/DMTA, time- and temperature-dependent viscoelastic properties were determined. Tack and shear adhesion of blends of the acrylic adhesive DuroTak® 87-4287 and ibuprofen at increasing concentrations were investigated. Interestingly, the probe tack test showed highest values at 1% ibuprofen concentration in the PSA and decreasing values with increasing ibuprofen concentrations. The shear adhesion of the PSA was decreased at all investigated ibuprofen concentrations. With DMA/DMTA, it could be demonstrated that antiplasticization and plasticization are responsible for the change in tack. The main reason for the decrease in shear adhesion is a shift of the Tg to lower temperatures, while antiplasticization only has a marginal effect. The term "antiplasticizing space" was introduced because antiplasticization depends on time, temperature, stress, strain, and API concentration. In general, this antiplasticizing space can have an impact on processing, stability, and in vivo behavior of API/polymer blends in drug formulations.
Assuntos
Adesivos/administração & dosagem , Adesivos/química , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Plastificantes/administração & dosagem , Plastificantes/química , Administração Cutânea , Química Farmacêutica/métodos , Polímeros/administração & dosagem , Polímeros/química , Pressão , Temperatura , Adesivo TransdérmicoRESUMO
Chemotherapy is the most common treatment for cancer. However, multidrug resistance (MDR) remains a major obstacle to effective chemotherapy, limiting the efficacy of both conventional chemotherapeutic and novel biologic agents. The constitutive androstane receptor (CAR), a xenosensor, is a key regulator of MDR. It functions in xenobiotic detoxification by regulating the expression of phase I drug-metabolizing enzymes and ATP-binding cassette (ABC) transporters, whose overexpression in cancers and whose role in drug resistance make them potential therapeutic targets for reducing MDR. MicroRNAs (miRNAs) are endogenous negative regulators of gene expression and have been implicated in most cellular processes, including drug resistance. Here, we report the inversely related expression of miR-137 and CAR in parental and doxorubicin-resistant neuroblastoma cells, wherein miR-137 is downregulated in resistant cells. miR-137 overexpression resulted in downregulation of CAR protein and mRNA (via mRNA degradation); it sensitized doxorubicin-resistant cells to doxorubicin (as shown by reduced proliferation, increased apoptosis and increased G2-phase cell cycle arrest) and reduced the in vivo growth rate of neuroblastoma xenografts. We observed similar results in cellular models of hepatocellular and colon cancers, indicating that the doxorubicin-sensitizing effect of miR-137 is not tumor type-specific. Finally, we show for the first time a negative feedback loop whereby miR-137 downregulates CAR expression and CAR downregulates miR-137 expression. Hypermethylation of the miR-137 promoter and negative regulation of miR-137 by CAR contribute in part to reduced miR-137 expression and increased CAR and MDR1 expression in doxorubicin-resistant neuroblastoma cells. These findings demonstrate that miR-137 is a crucial regulator of cancer response to doxorubicin treatment, and they identify miR-137 as a highly promising target to reduce CAR-driven doxorubicin resistance.
Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Neuroblastoma/patologia , Receptores Citoplasmáticos e Nucleares/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica , Receptor Constitutivo de Androstano , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Retroalimentação Fisiológica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/fisiopatologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Receptores Citoplasmáticos e Nucleares/metabolismoRESUMO
We analysed an outbreed mouse line which was selected for the phenotype 'high fertility' for 158 generations. During this selection period the mouse strain increased the number of offspring per litter from 10.4 to 17.1 and the total litter weight up to ~160%. In this study, we initially characterize the reproductive phenotype of high fertility males. Surprisingly, male bucks of the fertility line (FL1) show reduced percentage of motile and progressive motile spermatozoa; however, other sperm motility characteristics (e.g. velocity parameters) are improved compared with an unselected control line. Cytometrical investigation of the testicular cell-type composition indicated a significant increased concentration of diploid cells by a concomitant reduction in haploid cells in the testicular parenchyma of FL1. Furthermore, total testosterone concentrations in blood are dramatically increased in FL1 (>20 ng/mL). In line with increased testosterone levels, we observed increased expression rates of steroidogenic key enzymes Cyp11 and Cyp17 from FL1 testis samples. These data indicate that FL1 males have a manifest 'high fertility phenotype'. Diallelic crosses imply that male-only contribution largely determines the reproductive outcome in cross-breeding experiments. FL1 therefore is a promising model for future investigations on male factor (in)fertility. Our observation might also offer valuable cues for human reproductive medicine.
Assuntos
Fertilidade/genética , Tamanho da Ninhada de Vivíparos/genética , Animais , Cruzamento , Expressão Gênica , Masculino , Camundongos , Modelos Animais , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Esteroide 17-alfa-Hidroxilase/biossíntese , Testículo/enzimologia , Testículo/metabolismo , Testosterona/sangueRESUMO
Adaptation of wild-type p53 expressing UKF-NB-3 cancer cells to the murine double minute 2 inhibitor nutlin-3 causes de novo p53 mutations at high frequency (13/20) and multi-drug resistance. Here, we show that the same cells respond very differently when adapted to RITA, a drug that, like nutlin-3, also disrupts the p53/Mdm2 interaction. All of the 11 UKF-NB-3 sub-lines adapted to RITA that we established retained functional wild-type p53 although RITA induced a substantial p53 response. Moreover, all RITA-adapted cell lines remained sensitive to nutlin-3, whereas only five out of 10 nutlin-3-adapted cell lines retained their sensitivity to RITA. In addition, repeated adaptation of the RITA-adapted sub-line UKF-NB-3(r)RITA(10 µM) to nutlin-3 resulted in p53 mutations. The RITA-adapted UKF-NB-3 sub-lines displayed no or less pronounced resistance to vincristine, cisplatin, and irradiation than nutlin-3-adapted UKF-NB-3 sub-lines. Furthermore, adaptation to RITA was associated with fewer changes at the expression level of antiapoptotic factors than observed with adaptation to nutlin-3. Transcriptomic analyses indicated the RITA-adapted sub-lines to be more similar at the gene expression level to the parental UKF-NB-3 cells than nutlin-3-adapted UKF-NB-3 sub-lines, which correlates with the observed chemotherapy and irradiation sensitivity phenotypes. In conclusion, RITA-adapted cells retain functional p53, remain sensitive to nutlin-3, and display a less pronounced resistance phenotype than nutlin-3-adapted cells.
Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Furanos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Análise por Conglomerados , Furanos/uso terapêutico , Humanos , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Mutação , Neuroblastoma/tratamento farmacológico , Fenótipo , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transcriptoma , Proteína Supressora de Tumor p53/genética , Vincristina/farmacologia , Vincristina/uso terapêuticoRESUMO
A low-salt diet is known to decrease and salt excess to increase blood pressure in humans and rodents. Sex steroids seem to play a role in salt dependent hypertension. However, little is known about sex differences in mineralocorticoid receptor blockade between male and female rats. The objective of the work was at first to investigate the effects of a low-salt vs. a high-salt diet on blood pressure without the influence of gonadal steroids in male and female rats. Second, to determine the sex-specific effects of mineralocorticoid receptor blockade by spironolactone in high-salt and low-salt fed gonadectomized male and female animals. Normotensive male and female Wistar rats were gonadectomized and put on a low (NaCl<0.03%) or high (NaCl=4%) salt diet. On each diet animals received spironolactone or placebo. Blood pressure was measured by tail-cuff-method; 24-h urine samples were collected in metabolic cages and blood was collected for hormonal measurements. High-salt diet significantly increased systolic blood pressure in both sexes. This effect could be blocked effectively by spironolactone only in male rats. Spironolactone treatment significantly increased aldosterone levels in males and females independent of the sodium content of the diet. High sodium diet significantly increased relative kidney weight, which was not altered by spironolactone treatment. Independently of gonadal steroids a high-salt diet increased blood pressure in gonadectomized male and female rats. Spironolactone lowered blood pressure only in male not in female rats on a high-salt diet clearly indicating sex-specific effects of the mineralo-corticoid antagonist spironolactone.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Gônadas/cirurgia , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Antagonistas de Receptores de Mineralocorticoides/administração & dosagem , Espironolactona/administração & dosagem , Aldosterona/metabolismo , Animais , Feminino , Gônadas/metabolismo , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Masculino , Orquiectomia , Ovariectomia , Ratos , Ratos Wistar , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Fatores SexuaisRESUMO
The human cytomegalovirus (HCMV) is suspected to increase tumour malignancy by infection of cancer and/or stroma cells (oncomodulation). So far, oncomodulatory mechanisms have been attributed to the presence of HCMV and direct action of its gene products on cancer cells. Here, we investigated whether the prolonged presence of HCMV can result in the irreversible selection of a cancer cell population with increased malignancy. The neuroblastoma cell line UKF-NB-4 was long-term (200 passages) infected with the HCMV strain Hi91 (UKF-NB-4(Hi)) before virus eradication using ganciclovir (UKF-NB-4(HiGCV)). Global gene expression profiling of UKF-NB-4, UKF-NB-4(Hi) and UKF-NB-4(HiGCV) cells and subsequent bioinformatic signal transduction pathway analysis revealed clear differences between UKF-NB-4 and UKF-NB-4(Hi), as well as between UKF-NB-4 and UKF-NB-4(HiGCV) cells, but only minor differences between UKF-NB-4(Hi) and UKF-NB-4(HiGCV) cells. Investigation of the expression of a subset of five genes in different chronically HCMV-infected cell lines before and after virus eradication suggested that long-term HCMV infection reproducibly causes specific changes. Array comparative genomic hybridisation showed virtually the same genomic differences for the comparisons UKF-NB-4(Hi)/UKF-NB-4 and UKF-NB-4(HiGCV)/UKF-NB-4. UKF-NB-4(Hi) cells are characterised by an increased invasive potential compared with UKF-NB-4 cells. This phenotype was completely retained in UKF-NB-4(HiGCV) cells. Moreover, there was a substantial overlap in the signal transduction pathways that differed significantly between UKF-NB-4(Hi)/UKF-NB-4(HiGCV) and UKF-NB-4 cells and those differentially regulated between tumour tissues from neuroblastoma patients with favourable or poor outcome. In conclusion, we present the first experimental evidence that long-term HCMV infection can result in the selection of tumour cell populations with enhanced malignancy.
RESUMO
Six p53 wild-type cancer cell lines from infrequently p53-mutated entities (neuroblastoma, rhabdomyosarcoma, and melanoma) were continuously exposed to increasing concentrations of the murine double minute 2 inhibitor nutlin-3, resulting in the emergence of nutlin-3-resistant, p53-mutated sublines displaying a multi-drug resistance phenotype. Only 2 out of 28 sublines adapted to various cytotoxic drugs harboured p53 mutations. Nutlin-3-adapted UKF-NB-3 cells (UKF-NB-3(r)Nutlin(10 µM), harbouring a G245C mutation) were also radiation resistant. Analysis of UKF-NB-3 and UKF-NB-3(r)Nutlin(10 µM) cells by RNA interference experiments and lentiviral transduction of wild-type p53 into p53-mutated UKF-NB-3(r)Nutlin(10 µM) cells revealed that the loss of p53 function contributes to the multi-drug resistance of UKF-NB-3(r)Nutlin(10 µM) cells. Bioinformatics PANTHER pathway analysis based on microarray measurements of mRNA abundance indicated a substantial overlap in the signalling pathways differentially regulated between UKF-NB-3(r)Nutlin(10 µM) and UKF-NB-3 and between UKF-NB-3 and its cisplatin-, doxorubicin-, or vincristine-resistant sublines. Repeated nutlin-3 adaptation of neuroblastoma cells resulted in sublines harbouring various p53 mutations with high frequency. A p53 wild-type single cell-derived UKF-NB-3 clone was adapted to nutlin-3 in independent experiments. Eight out of ten resulting sublines were p53-mutated harbouring six different p53 mutations. This indicates that nutlin-3 induces de novo p53 mutations not initially present in the original cell population. Therefore, nutlin-3-treated cancer patients should be carefully monitored for the emergence of p53-mutated, multi-drug-resistant cells.
Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Imidazóis/farmacologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Adaptação Biológica/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 7/metabolismo , Humanos , Mutação , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Interferência de RNA , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismoRESUMO
Slow changes in [Ca(2+)](i) reflect increased neuronal activity. Our study demonstrates that single-trial fast [Ca(2+)](i) imaging (≥200 Hz sampling rate) revealed peaks each of which are associated with single spike discharge recorded by consecutive voltage-sensitive dye (VSD) imaging in enteric neurones and nerve fibres. Fast [Ca(2+)](i) imaging also revealed subthreshold fast excitatory postsynaptic potentials. Nicotine-evoked [Ca(2+)](i) peaks were reduced by -conotoxin and blocked by ruthenium red or tetrodotoxin. Fast [Ca(2+)](i) imaging can be used to directly record single action potentials in enteric neurones. [Ca(2+)](i) peaks required opening of voltage-gated sodium and calcium channels as well as Ca(2+) release from intracellular stores.
Assuntos
Potenciais de Ação/fisiologia , Cálcio/fisiologia , Plexo Mientérico/fisiologia , Neurônios/fisiologia , Compostos de Anilina/farmacologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Corantes Fluorescentes/farmacologia , Cobaias , Humanos , Íleo/fisiologia , Masculino , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Compostos de Piridínio/farmacologia , Rutênio Vermelho/farmacologia , Tetrodotoxina/farmacologia , Imagens com Corantes Sensíveis à Voltagem , Xantenos/farmacologia , ômega-Conotoxinas/farmacologiaRESUMO
PURPOSE: Renal cell carcinoma (RCC) is highly resistant to chemotherapy and unresponsive to radio- and immunotherapy. Recently, we have documented that the histone deacetylase (HDAC)-inhibitor valproic acid (VPA) in combination with low-dosed interferon (IFN)-alpha significantly inhibits RCC proliferation and adhesion in vitro and in vivo. The current study investigated the effects of these compounds on gene transcription of metastatic RCC cell line Caki-1 after 3 and 5 days exposure. METHODS: To evaluate the gene expression profiles of the RCC cells, we performed microarray analysis using Affymetrix GeneChip. Selected significant genes were further validated by Real Time PCR. RESULTS: Microarray revealed that VPA altered genes that are involved in cell growth, cell survival, immune response, cell motility and cell adhesion. Combination of VPA with IFN-alpha not only enhanced the effects on gene transcription but also resulted in the expression of novel genes, which were not induced by either VPA or IFN-alpha alone. Among the up-regulated genes were chemokines (CXCL10, CXCL11, CXCL16) and integrins (ITGA2, ITGA4, ITGA5, ITGA6, ITGA7). Genes encoding for adhesion molecules (NCAM1, ICAM1, VCAM1) were also modulated. Real Time PCR approved these findings. CONCLUSION: This data provides insight into the molecular mechanism of action of the combined treatment of VPA and IFN-alpha in RCC. Implications are that the combined application of VPA and IFN-alpha may represent a more efficient alternative to existing therapy options for RCC.
Assuntos
Carcinoma de Células Renais/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Interferon-alfa/farmacologia , Neoplasias Renais/genética , Ácido Valproico/farmacologia , Carcinoma de Células Renais/patologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Fatores Imunológicos/farmacologia , Neoplasias Renais/patologia , Análise em MicrossériesRESUMO
The cysteine protease cathepsin B acts as a key player in apoptosis. Cathepsin B-mediated cell death is induced by various stimuli such as ischemia, bile acids or TNFα. Whether cathepsin B can be influenced by anticancer drugs, however, has not been studied in detail. Here, we describe the modulation of doxorubicin-induced cell death by silencing of cathepsin B expression. Previously, it was shown that doxorubicin, in contrast to other drugs, selectively regulates expression and activity of cathepsin B. Selective silencing of cathepsin B by siRNA or the cathepsin B specific inhibitor CA074Me modified doxorubicin-mediated cell death in Hela tumor cells. Both Caspase 3 activation and PARP cleavage were significantly reduced in cells lacking cathepsin B. Moreover, mitochondrial membrane permeabilization as well as the release of cytochrome C and AIF from mitochondria into cytosol induced by doxorubicin were significantly diminished in cathepsin B suppressed cells. In addition, doxorubicin associated down-regulation of XIAP was not observed in cathepsin B silenced cells. Lack of cathepsin B significantly modified cell cycle regulatory proteins such as cdk1, Wee1 and p21 without significant changes in G(1), S or G(2)M cell cycle phases maybe indicating further cell cycle independent actions of these proteins. Consequently, cell viability following doxorubicin was significantly elevated in cells with cathepsin B silencing. In summary, our data strongly suggest a role of cathepsin B in doxorubicin-induced cell death. Therefore, increased expression of cathepsin B in various types of cancer can modify susceptibility towards doxorubicin.
Assuntos
Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Catepsina B/biossíntese , Doxorrubicina/farmacologia , Fator de Indução de Apoptose/metabolismo , Caspase 3/metabolismo , Catepsina B/antagonistas & inibidores , Catepsina B/genética , Proteínas de Ciclo Celular/metabolismo , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Citosol/efeitos dos fármacos , Citosol/metabolismo , Dipeptídeos/farmacologia , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , RNA Interferente Pequeno/farmacologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismoRESUMO
In April 2009, a novel H1N1 influenza A virus, the so-called pandemic H1N1/09 virus (former designations include swine influenza, novel influenza, swine-origin influenza A [H1N1] virus [S-OIV], Mexican flu, North American Flu) was identified in Mexico. The virus has since spread throughout the world and caused an influenza pandemic as defined by the criteria of the World Health Organization. This represents the first influenza A virus pandemic since the emergence of H3N2 (''Hong Kong'' Flu) in 1968. Vaccine production has started, and vaccines are expected to become available during the course of 2009. Although the pandemic H1N1/09 virus originates from the triple-reassortant swine influenza (H1) virus circulating in North American pigs, it is not epidemic in pigs. Although the H1N1/09 virus pandemic is currently mild, concerns remain that it may become more aggressive during spreading. The distribution of proper information to the public on the status of the H1N1/09 virus pandemic will be important to achieve a broad awareness of the potential risks and the optimum code of behavior during the pandemic. Here, the features of pandemic H1N1/09 virus are discussed within the framework of knowledge gained from previous influenza A virus pandemics.
Assuntos
Surtos de Doenças , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/epidemiologia , Influenza Humana/virologia , Antivirais/uso terapêutico , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/tratamento farmacológico , Influenza Humana/transmissão , Proteínas Virais , Fatores de VirulênciaRESUMO
Phosphorus (P) is an essential element for all living organisms and cannot be replaced. Municipal sewage sludge is a carrier of phosphorus, but also contains organic pollutants and heavy metals. A two-step thermal treatment is suggested, including mono-incineration of sewage sludge and subsequent thermochemical treatment of the ashes. Organic pollutants are completely destroyed by mono-incineration. The resulting sewage sludge ashes contain P, but also heavy metals. P in the ashes exhibits low bioavailability, a disadvantage in farming. Therefore, in a second thermochemical step, P is transferred into mineral phases available for plants, and heavy metals are removed as well. The thermochemical treatment was investigated in a laboratory-scale rotary furnace by treating seven different sewage sludge ashes under systematic variation of operational parameters. Heavy metal removal and the increase of the P-bioavailability were the focus of the investigation. The present experimental study shows that these objectives have been achieved with the proposed process. The P-bioavailability was significantly increased due to the formation of new mineral phases such as chlorapatite, farringtonite and stanfieldite during thermochemical treatment.