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2.
Hautarzt ; 69(10): 815-824, 2018 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-30191254

RESUMEN

BACKGROUND: Clinical registries may provide high-quality evidence on the use and effectiveness of therapeutic interventions under real-life conditions. Adults with moderate-to-severe atopic eczema (atopic dermatitis [AD]) are enrolled into TREATgermany and prospectively followed over at least 2 years. This paper analyses the association between dermatological quality of life and work limitations. MATERIALS AND METHODS: Treatment modalities and a broad set of physician- and patient-reported outcome measures are documented using validated instruments to assess clinical disease severity (EASI [Eczema Area and Severity Index], objective SCORAD [objective-SCORing Atopic Dermatitis]), quality of life (DLQI [Dermatology Life Quality Index]), symptoms (POEM [Patient-oriented Eczema Measure]), global disease severity, as well as patient satisfaction and work limitations including presenteeism (WLQ [Work Limitation Questionnaire]). From 06/2016 until 12/2017, 241 individuals (mean age 43 ± 15 years, 38.6% female) were enrolled at 19 recruitment centers; 69% of the patients were employed. RESULTS: Employed persons had DLQI and WLQ scores of 10.6 ± 6.9 points and 17.7 ± 18.1%, respectively. Mean presenteeism was substantial accounting for 9.2%. With coefficients of 0.39 and 0.33 WLQ and presenteeism scores significantly correlate with DLQI (p < 0.000). Bootstrapped regression models showed that the limitations in coping with work requirements increase by 1.7% as DLQI increases by one point. Lower quality of life due to AD is most strongly associated with limitations in the area of physical and performance requirements in general. Presenteeism increases by 0.5% as DLQI increases by one point. CONCLUSION: Moderate-to-severe AD has substantial adverse economic impact with mean productivity loss of patients of almost 10%. Future analyses from TREATgermany will address the impact of innovative treatment modalities on quality of life and work productivity of patients with moderate-to-severe AD.


Asunto(s)
Competencia Clínica , Dermatitis Atópica , Eccema , Sistema de Registros , Adulto , Dermatitis Atópica/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Índice de Severidad de la Enfermedad
3.
Cell Death Differ ; 15(3): 600-12, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18188168

RESUMEN

The proteasome inhibitor bortezomib, which induces cell death in various cancer cell lines including lymphatic neoplasias, has recently been approved for the treatment of relapsed multiple myeloma. Important mechanisms of proteasome inhibitor-mediated tumor cell death are the inhibition of NF-kappaB activation and induction of the terminal unfolded protein response (UPR). However, little is known about effects of bortezomib on developing and mature lymphocytes. Therefore, Balb/C mice were injected with bortezomib and lymphocyte subsets were analyzed. This treatment resulted in dramatically decreased numbers of T and B lymphocyte precursors, while mature lymphocytes were only partially affected. Thymocytes were almost depleted 3 days after a single bortezomib injection, pro-B and pre-B cells already after 2 days. Thymocytes and B cell precursors recovered within 2 weeks. The decreased numbers of developing lymphocytes were due to apoptotic cell death accompanied by strongly increased caspase 3/7 activity. Within 8 h after bortezomib injection, there was a strong induction of heat shock protein 70 and C/EBP homologous protein in bone marrow B cells, indicating endoplasmic reticulum stress and activation of the terminal UPR, respectively. Hence, induction of apoptosis by proteasome inhibition can dramatically affect lymphocyte development, a fact which has important implications for the clinical use of bortezomib, especially in situations with ongoing lymphopoiesis.


Asunto(s)
Apoptosis , Ácidos Borónicos/farmacología , Células Precursoras de Linfocitos B/efectos de los fármacos , Células Precursoras de Linfocitos T/efectos de los fármacos , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasoma , Pirazinas/farmacología , Animales , Subgrupos de Linfocitos B/citología , Subgrupos de Linfocitos B/efectos de los fármacos , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/inmunología , Bortezomib , Células Cultivadas , Femenino , Recuento de Linfocitos , Tejido Linfoide/citología , Tejido Linfoide/efectos de los fármacos , Tejido Linfoide/inmunología , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Células Precursoras de Linfocitos B/citología , Células Precursoras de Linfocitos T/citología , Pliegue de Proteína , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/efectos de los fármacos , Timo/citología , Timo/efectos de los fármacos , Timo/inmunología
4.
Mycorrhiza ; 17(4): 279-290, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17235552

RESUMEN

Ectomycorrhizal (ECM) communities were assessed on a 720 m(2) plot along a chronosequence of red oak (Quercus rubra) stands on a forest reclamation site with disturbed soil in the lignite mining area of Lower Lusatia (Brandenburg, Germany). Adjacent to the mining area, a red oak reference stand with undisturbed soil was investigated reflecting mycorrhiza diversity of the intact landscape. Aboveground, sporocarp surveys were carried out during the fruiting season in a 2-week interval in the years 2002 and 2003. Belowground, ECM morphotypes were identified by comparing sequences of the internal transcribed spacer regions from nuclear rDNA with sequences from the GenBank database. Fifteen ECM fungal species were identified as sporocarps and 61 belowground as determined by morphological/anatomical and molecular analysis of their ectomycorrhizas. The number of ECM morphotypes increased with stand age along the chronosequence. However, the number of morphotypes was lower in stands with disturbed soil than with undisturbed soil. All stands showed site-specific ECM communities with low similarity between the chronosequence stands. The dominant ECM species in nearly all stands was Cenococcum geophilum, which reached an abundance approaching 80% in the 21-year-old chronosequence stand. Colonization rate of red oak was high (>95%) at all stands besides the youngest chronosequence stand where colonization rate was only 15%. This supports our idea that artificial inoculation with site-adapted mycorrhizal fungi would enhance colonization rate of red oak and thus plant growth and survival in the first years after outplanting.


Asunto(s)
Ecosistema , Micorrizas/clasificación , Quercus , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Monitoreo del Ambiente , Jardinería/métodos , Alemania , Minería , Técnicas de Tipificación Micológica , Micorrizas/genética , Raíces de Plantas/microbiología , Quercus/microbiología , Especificidad de la Especie , Factores de Tiempo
5.
Syst Biol (Stevenage) ; 153(6): 433-47, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17186705

RESUMEN

Complex cellular networks regulate regeneration, detoxification and differentiation of hepatocytes. By combining experimental data with mathematical modelling, systems biology holds great promises to elucidate the key regulatory mechanisms involved and predict targets for efficient intervention. For the generation of high-quality quantitative data suitable for mathematical modelling a standardised in vitro system is essential. Therefore the authors developed standard operating procedures for the preparation and cultivation of primary mouse hepatocytes. To reliably monitor the dynamic induction of signalling pathways, the authors established starvation conditions and evaluated the extent of starvation-associated stress by quantifying several metabolic functions of cultured primary hepatocytes, namely activities of glutathione-S-transferase, glutamine synthetase, CYP3A as well as secretion of lactate and urea into the culture medium. Establishment of constant metabolic activities after an initial decrease compared with freshly isolated hepatocytes showed that the cultured hepatocytes achieve a new equilibrium state that was not affected by our starving conditions. To verify the highly reproducible dynamic activation of signalling pathways in the in vitro system, the authors examined the JAK-STAT, SMAD, PI3 kinase, MAP kinase, NF-kappaB and Wnt/beta-catenin signalling pathways. For the induction of gp130, JAK1 and STAT3 phosphorylation IL6 was used, whereas TGFbeta was applied to activate the phosphorylation of SMAD1, SMAD2 and SMAD3. Both Akt/PKB and ERK1/2 phosphorylation were stimulated by the addition of hepatocyte growth factor. The time-dependent induction of a pool of signalling competent beta-catenin was monitored in response to the inhibition of GSK3beta. To analyse whether phosphorylation is actually leading to transcriptional responses, luciferase reporter gene constructs driven by multiple copies of TGFbeta-responsive motives were applied, demonstrating a dose-dependent increase in luciferase activity. Moreover, the induction of apoptosis by the TNF-like cytokine Fas ligand was studied in the in vitro system. Thus, the mouse hepatocyte in vitro system provides an important basis for the generation of high-quality quantitative data under standardised cell culture conditions that is essential to elucidate critical hepatocellular functions by the systems biology approach.


Asunto(s)
Citocinas/metabolismo , Hepatocitos/metabolismo , Modelos Animales , Modelos Biológicos , Complejos Multienzimáticos/metabolismo , Transducción de Señal/fisiología , Biología de Sistemas/normas , Animales , Simulación por Computador , Ratones
6.
Amino Acids ; 31(2): 137-56, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16868651

RESUMEN

The H(+)/peptide cotransporter PEPT2 is expressed in a variety of organs including kidney, lung, brain, mammary gland, and eye. PEPT2 substrates are di- and tripeptides as well as peptidomimetics, such as beta-lactam antibiotics. Due to the presence of PEPT2 at the bronchial epithelium, the aerosolic administration of peptide-like drugs might play a major role in future treatment of various pulmonary and systemic diseases. Moreover, PEPT2 has a significant influence on the in vivo disposition and half-life time of peptide-like drugs within the body, particularly in kidney and brain. PEPT2 is known to have similar but not identical structural requirements for substrate recognition and transport compared to PEPT1, its intestinal counterpart. In this review we compiled available affinity constants of 352 compounds, measured at different mammalian tissues and expression systems and compare the data whenever possible with those of PEPT1.


Asunto(s)
Riñón/metabolismo , Simportadores/metabolismo , Dipéptidos/farmacología , Humanos , Transportador de Péptidos 1 , Relación Estructura-Actividad , Simportadores/química , Simportadores/efectos de los fármacos
7.
Amino Acids ; 31(2): 111-7, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16699824

RESUMEN

The proton coupled amino acid transporter PAT1 expressed in intestine, brain, and other organs accepts L- and D-proline, glycine, and L-alanine but also pharmaceutically active amino acid derivatives such as 3-amino-1-propanesulfonic acid, L-azetidine-2-carboxylic acid, and cis-4-hydroxy-D-proline as substrates. We systematically analyzed the structural requirements for PAT1 substrates by testing 87 amino acids, proline homologs, indoles, and derivatives. Affinity data and effects on membrane potential were determined using Caco-2 cells. For aliphatic amino acids, a blocked carboxyl group, the distance between amino and carboxyl group, and the position of the hydroxyl group are affinity limiting factors. Methylation of the amino group enhances substrate affinity. Hetero atoms in the proline template are well tolerated. Aromatic alpha-amino acids display low affinity. PAT1 interacts strongly with heterocyclic aromatic acids containing an indole scaffold. The structural requirements of PAT1 substrates elucidated in this study will be useful for the development of prodrugs.


Asunto(s)
Sistemas de Transporte de Aminoácidos/metabolismo , Simportadores/metabolismo , Sistemas de Transporte de Aminoácidos/efectos de los fármacos , Células CACO-2 , Humanos , Potenciales de la Membrana , Especificidad por Sustrato , Simportadores/efectos de los fármacos
8.
J Neural Transm (Vienna) ; 112(7): 933-48, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15937638

RESUMEN

Measuring proteins in cerebrospinal fluid (CSF) has gained wide acceptance for the differential diagnosis of dementia. Some groups have already extended these investigations in Alzheimer's disease (AD) by asking how stable these markers are in follow-up analysis, if they depend on the stage of disease and whether they can be used to monitor the progression and biological effects of treatment. We evaluated 21 patients with dementia with Lewy bodies (DLB) and 19 patients with AD, on two occasions, with regard to levels of tau protein, tau protein phosphorylated at threonine 181 (p-tau), Abeta42, Abeta40 and S-100B protein, using a set of commercially available assays. Tau protein levels were lower in DLB in first and second LP compared to AD and decreased during course of both groups. P-tau levels were increased in AD and DLB and decreased during follow-up. Abeta42 and Abeta40 remained relatively stable during follow-up but we found a slight increase of the median Abeta42 level in DLB, whereas in AD, Abeta42 tends to decrease during follow-up. S-100B protein increased during follow-up in both diseases. The protein dynamics in DLB and AD are relatively similar. S-100B protein may be a useful marker for follow-up in neurodegenerative diseases but has to be analysed in longer follow-up periods. Tau protein may be used to differentiate between DLB and AD. Follow-up CSF analyses are of limited value for the differentiation of AD and DLB. We conclude that more specific markers have to be established for the differentiation and follow-up of these diseases.


Asunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Enfermedad por Cuerpos de Lewy/líquido cefalorraquídeo , Proteínas tau/líquido cefalorraquídeo , Acetilcolinesterasa/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Péptidos beta-Amiloides/metabolismo , Diagnóstico Diferencial , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Proteínas tau/metabolismo
9.
J Pept Res ; 63(5): 420-5, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15140159

RESUMEN

Four new analogues of arginine vasopressin (AVP) substituted in positions 2 and 3 with all possible combinations of enantiomers of N-methylphenylalanine were synthesized and studied to assess the influence of N-methylation of the peptide bonds between the first three amino acids on the pharmacological properties of the resulting peptides. The next three analogues were designed to learn how the shortening of the peptide chain, by removal of one of the N-methylphenylalanine residues, would affect pharmacological properties of the resulting compounds. The activity of the analogues was tested in the in vitro uterotonic, pressor and antidiuretic tests. None of the prepared analogues displayed significant biological activity with the exception of [Me-d-Phe(2), Me-Phe(3)]AVP and [Me-d-Phe(2,3)]AVP, which showed low antiuterotonic activity (pA(2) = 6.6 and pA(2) = 6.4, respectively). Our results, while not impressive in terms of biological activity, may be helpful for designing potent and selective oxytocin antagonists.


Asunto(s)
Arginina Vasopresina/farmacología , Presión Sanguínea/efectos de los fármacos , Diuresis/efectos de los fármacos , Contracción Uterina/efectos de los fármacos , Vasoconstrictores/farmacología , Animales , Arginina Vasopresina/análisis , Dipéptidos/química , Femenino , Metilación , Ratas , Ratas Wistar
10.
J Pept Res ; 63(1): 29-35, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14984571

RESUMEN

Two new analogues of a previously designed bradykinin (BK) antagonist, d-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-d-Phe-Thi-Arg, substituted in position 8 by N-benzylglycine and N-benzyl-l-alanine were designed, synthesized and bioassayed. The results show an impressive enhancement of B2 antagonistic potencies of both peptides in comparison with the model. In two further analogues these modifications were combined with acylation of the N-terminus with 1-adamantanacarboxylic acid. Acylated analogues exhibited higher antagonistic potency in comparison with the parent compounds, however, the range of effect was not as high as in previously described cases. The activity of analogues was assessed by their ability to inhibit vasodepressor response to exogenous BK (rat blood pressure test). Our results may be of value in the design of more potent BK antagonists.


Asunto(s)
Alanina/química , Bradiquinina/antagonistas & inhibidores , Glicina/análogos & derivados , Glicina/química , Oligopéptidos/síntesis química , Oligopéptidos/farmacología , Alanina/análogos & derivados , Animales , Presión Sanguínea/efectos de los fármacos , Bradiquinina/análogos & derivados , Masculino , Oligopéptidos/química , Ratas , Ratas Wistar
12.
Pharmazie ; 57(3): 176-7, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11933845

RESUMEN

A simple, rapid and reproducible procedure for the identification of extracellular Californian poppy (Eschscholzia californica Cham.) beta-galactosidase is described using callus cultures of seedlings from the tested plant, roots of 4-days-old seedlings of Californian poppy germinating on agar plates and cell suspension cultures cultivated from callus cultures. 6-Bromo-2-naphthyl-beta-D-galactopyranoside and p-nitrophenyl-beta-D-galactopyranoside were used as substrates for the determination of the intracellular and extracellular activities of beta-galactosidase. The extracellular beta-galactosidase activity was identified by evaluating the dye-zones in an agar medium. The enzyme from Californian poppy callus cultures or from seedling roots cultivated on agar plates supplemented with 6-bromo-2-naphthyl-galactopyranoside hydrolyzed this substrate releasing 6-bromo-2-naphthol. By simultaneous coupling with hexazonium p-rosaniline the corresponding (reddish-brown) azo-dye was formed. The agar plate method described permits rapid, simple and specific detection of plant producers of extracellular beta-galactosidase.


Asunto(s)
Plantas/enzimología , beta-Galactosidasa/análisis , Células Cultivadas , Espacio Extracelular/enzimología , Galactósidos/química , Indicadores y Reactivos , Papaver/química , Reproducibilidad de los Resultados
13.
Biol Trace Elem Res ; 81(1): 71-8, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11508333

RESUMEN

It is known that peroxides, which are increased during Se deficiency because of reduced glutathione peroxidase (GSH-Px) activity, can influence the prostacyclin I2/thromboxane A2 (PGI2/TXA2) ratio. In this study we analyzed the PGI2 and TXA2 formation of aortas of long-term Se-deficient rats. Despite low GSH-Px activity in the Se-deficient group, the basal PGI2 and TXA2 formation was not different versus control animals (PGI2: 2295+/-1134 pg/mg vs 2940+/-1134 pg/mg; TXA2: 3.83+/-1.06 pg/mg vs 5.67+/-2.99 pg/mg). However, we checked the capacity of the aortas of Se-deficient rats to compensate for a suddenly increased peroxide concentration. After peroxide stimulation, the PGI2 release was significantly lower in the Se-deficient group compared to the control group (PGI2: 3507+/-1829 pg/mg vs 7986+/-2636 pg/mg). Again, the TXA2 release did not show any differences. The release ratio of PGI2/TXA2 decreased under peroxide stress in Se-deficient animals. Although long-term Se deficiency showed a relatively well-balanced metabolism under resting conditions, sudden stress, accompanied by an excessive radical production, cannot be compensated.


Asunto(s)
Aorta/metabolismo , Enfermedades Carenciales/metabolismo , Epoprostenol/metabolismo , Selenio/deficiencia , Tromboxano A2/metabolismo , Animales , Aorta/enzimología , Glutatión Peroxidasa/metabolismo , Técnicas In Vitro , Masculino , Ratas , Ratas Wistar
14.
Microvasc Res ; 62(2): 114-27, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11516240

RESUMEN

To investigate the relevance of *NO and oxyradicals in the blood-brain barrier (BBB), differentiated and well-proliferating brain capillary endothelial cells (BCEC) are required. Therefore, rat BCEC (rBCEC) were transfected with immortalizing genes. The resulting lines exhibited endothelial characteristics (factor VIII, angiotensin-converting enzyme, high prostacyclin/thromboxane release rates) and BBB markers (gamma-glutamyl transpeptidase, alkaline phosphatase). The control line rBCEC2 (mock transfected) revealed fibroblastoid morphology, less factor VIII, reduced gamma-glutamyl transpeptidase, weak radical defence, low prostanoid metabolism, and limited proliferation. Lines transfected with immortalizing genes (especially rBCEC4, polyoma virus large T antigen) conserved primary properties: epitheloid morphology, subcultivation with high proliferation rate under pure culture conditions, and powerful defence against reactive oxygen species (Mn-, Cu/Zn-superoxide dismutase, catalase, glutathione peroxidase, glutathione) effectively controlling radical metabolism. Only 100 microM H2O2 overcame this defence and stimulated the formation of eicosanoids similarly as in primary cells. Some BBB markers were expressed to a lower degree; however, cocultivation with astrocytes intensified these markers (e.g., alkaline phosphatase) and paraendothelial tightness, indicating induction of BBB properties. Inducible NO synthase was induced by a cytokine plus lipopolysaccharide mixture in all lines and primary cells, resulting in *NO release. Comparing the cell lines obtained, rBCEC4 are stable immortalized and reveal the best conservation of properties from primary cells, including enzymes producing or decomposing reactive species. These cells can be subcultivated in large amounts and, hence, they are suitable to study the role of radical metabolism in the BBB and in the cerebral microvasculature.


Asunto(s)
Barrera Hematoencefálica , Encéfalo/irrigación sanguínea , Línea Celular , Endotelio Vascular/citología , Óxido Nítrico/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Biomarcadores , Encéfalo/citología , Encéfalo/metabolismo , Capilares/citología , División Celular , Citocinas/farmacología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Epoprostenol/metabolismo , Radicales Libres/metabolismo , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico Sintasa de Tipo III , Ratas , Ratas Wistar , Tromboxano A2/metabolismo
15.
Mult Scler ; 7(3): 173-7, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11475441

RESUMEN

The present report describes immunopathological, radiologcal and serological characteristics of antibody-mediated demyelination in a multiple sclerosis (MS) case with the main findings: (1) immunoglobulin and complement deposits in areas of active demyelination accompanied by massive macrophage activation; (2) ring-enhancing lesions in T1-weighted MRI after gadolinium application; (3) high titers of serum anti-myelin antibodies; and (4) signs of macrophage activation in the serum. Plasmapheresis may be a successful treatment for the type of inflammatory demyelination shown in the present case.


Asunto(s)
Enfermedades Desmielinizantes/inmunología , Enfermedades Desmielinizantes/patología , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Autoanticuerpos/sangre , Biomarcadores , Sistema Nervioso Central/diagnóstico por imagen , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/patología , Enfermedades Desmielinizantes/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico por imagen , Proteínas de la Mielina/inmunología , Plasmaféresis , Radiografía
16.
Biochemistry ; 40(14): 4454-8, 2001 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-11284702

RESUMEN

This study was initiated to develop inhibitors of the intestinal H(+)/peptide symporter. We provide evidence that the dipeptide derivative Lys[Z(NO(2))]-Pro is an effective competitive inhibitor of mammalian PEPT1 with an apparent binding affinity of 5-10 microM. Characterization of the interaction of Lys[Z(NO(2))]-Pro with the substrate binding domain of PEPT1 has been performed in (a) monolayer cultures of human Caco-2 cells expressing PEPT1, (b) transgenic Pichia pastoris cells expressing PEPT1, and (c) Xenopus laevis oocytes expressing PEPT1. By competitive uptake studies with radiolabeled dipeptides, HPLC analysis of Lys[Z(NO(2))]-Pro in cells, and electrophysiological techniques, we unequivocally show that Lys[Z(NO(2))]-Pro binds with high affinity to PEPT1, competes competitively with various dipeptides for uptake into cells, but is not transported itself. Lack of transport was substantiated by the absence of Lys[Z(NO(2))]-Pro in Caco-2 cell extracts as determined by HPLC analysis, and by the absence of any positive inward currents in oocytes when exposed to the inhibitor. The fact that Lys[Z(NO(2))]-Pro can bind to PEPT1 from the extracellular as well as the intracellular site was shown in the oocyte expression system by a strong inhibition of dipeptide-induced currents under voltage clamp conditions. Our findings serve as a starting point for the identification of the substrate binding domain in the PEPT1 protein as well as for studies on the physiological and pharmacological role of PEPT1.


Asunto(s)
Proteínas Portadoras/antagonistas & inhibidores , Proteínas Portadoras/metabolismo , Dipéptidos/metabolismo , Nitrobencenos/metabolismo , Simportadores , Animales , Unión Competitiva , Transporte Biológico Activo/efectos de los fármacos , Células CACO-2/metabolismo , Proteínas Portadoras/biosíntesis , Dipéptidos/antagonistas & inhibidores , Dipéptidos/farmacología , Humanos , Cinética , Nitrobencenos/farmacología , Oocitos/metabolismo , Técnicas de Placa-Clamp , Transportador de Péptidos 1 , Pichia/genética , Pichia/metabolismo , Xenopus laevis
17.
J Pept Res ; 57(1): 11-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11168884

RESUMEN

The present paper describes the synthesis and some pharmacological properties of two new bradykinin analogues containing the ethylene-bridged dipeptide Phe-Phe in their molecules. In a further two peptides this modification was combined with acylation of the N-terminus with 1-adamantaneacetic acid. Finally, we synthesized four analogues by removing the Ser6 residue from the four peptides mentioned above. The activity of the new analogues was assayed on isolated rat uterus (RUT) and in rat blood pressure tests (BPT). The results clearly indicate that the proposed modification, alone or in combination with other changes, resulted in either a drop in antiuterotonic activity or even in conversion to an agonism. Although this tendency is not so distinct in blood pressure assays, the antagonistic potency of the new analogues is also diminished. Nevertheless, it was demonstrated that the D-amino acid in position 7 which, until recently, was considered necessary for antagonism, may be replaced, together with the amino acid occupying position 8, by a suitable, sterically restricted L,L-dipeptide unit.


Asunto(s)
Adamantano/análogos & derivados , Adamantano/síntesis química , Bradiquinina/análogos & derivados , Bradiquinina/síntesis química , Péptidos/química , Ácido Acético/química , Adamantano/farmacología , Secuencia de Aminoácidos , Aminoácidos/química , Animales , Presión Sanguínea/efectos de los fármacos , Bradiquinina/farmacología , Femenino , Masculino , Datos de Secuencia Molecular , Fenilalanina/química , Conformación Proteica , Ratas , Ratas Wistar , Útero/efectos de los fármacos
18.
J Immunol ; 166(3): 2041-8, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11160254

RESUMEN

CD26 or dipeptidyl peptidase IV (DP IV) is expressed on various cell types, including T cells. Although T cells can receive activating signals via CD26, the physiological role of CD26/DP IV is largely unknown. We used the reversible DP IV inhibitor Lys[Z(NO(2))]-pyrrolidide (I40) to dissect the role of DP IV in experimental autoimmune encephalomyelitis (EAE) and to explore the therapeutic potential of DP IV inhibition for autoimmunity. I40 administration in vivo decreased and delayed clinical and neuropathological signs of adoptive transfer EAE. I40 blocked DP IV activity in vivo and increased the secretion of the immunosuppressive cytokine TGF-beta1 in spinal cord tissue and plasma during acute EAE. In vitro, while suppressing autoreactive T cell proliferation and TNF-alpha production, I40 consistently up-regulated TGF-beta1 secretion. A neutralizing anti-TGF-beta1 Ab blocked the inhibitory effect of I40 on T cell proliferation to myelin Ag. DP IV inhibition in vivo was not generally immunosuppressive, neither eliminating encephalitogenic T cells nor inhibiting T cell priming. These data suggest that DP IV inhibition represents a novel and specific therapeutic approach protecting from autoimmune disease by a mechanism that includes an active TGF-beta1-mediated antiinflammatory effect at the site of pathology.


Asunto(s)
Dipeptidil Peptidasa 4/metabolismo , Encefalomielitis Autoinmune Experimental/enzimología , Encefalomielitis Autoinmune Experimental/prevención & control , Factor de Crecimiento Transformador beta/metabolismo , Regulación hacia Arriba , Animales , División Celular/inmunología , Células Cultivadas , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Activación Enzimática/efectos de los fármacos , Activación Enzimática/inmunología , Femenino , Adyuvante de Freund/administración & dosificación , Inhibidores de Crecimiento/fisiología , Terapia de Inmunosupresión , Inyecciones Intraperitoneales , Inyecciones Subcutáneas , Activación de Linfocitos , Lisina/administración & dosificación , Lisina/análogos & derivados , Lisina/farmacología , Ratones , Proteína Básica de Mielina/administración & dosificación , Proteína Básica de Mielina/inmunología , Inhibidores de Proteasas/administración & dosificación , Inhibidores de Proteasas/farmacología , Pirrolidinas/administración & dosificación , Pirrolidinas/farmacología , Subgrupos de Linfocitos T/inmunología , Factor de Crecimiento Transformador beta/biosíntesis , Factor de Crecimiento Transformador beta/fisiología , Factor de Crecimiento Transformador beta1 , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/inmunología
19.
Biochim Biophys Acta ; 1479(1-2): 15-31, 2000 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11004527

RESUMEN

Aminopeptidase P (APP), dipeptidyl peptidase II (DP II), dipeptidyl peptidase IV (DP IV) and prolyl oligopeptidase (POP) are proline specific peptidases. Hence, they are able to cleave peptide bonds containing the imino acid proline. Amino acid pyrrolidides (Pyrr) and thiazolidides (Thia) are well-known product analogue inhibitors of DP IV and POP. For the first time we describe the influence of a thioxo amide bond, incorporated into these compounds, on the inhibition of the proline specific peptidases. Taking into account the substrate specificity of these peptidases, we have synthesized Xaa-psi[CS-N]-Pyrr and Xaa-psi[CS-N]-Thia of the amino acids Ala, Phe, Val and Ile. The inhibition constants were determined for the above mentioned proline specific peptidases isolated from different sources. As a result, the serine proteases DP II, DP IV and POP were inhibited competitively, whereas metal-dependent APP displayed a linear mixed-type inhibition with inhibition constants up to 10(-4) M. Thioxylation of Xaa-Pyrr and Xaa-Thia led to a slight decrease of inhibition of DP IV and POP compared to Xaa-Pyrr and Xaa-Thia, though the inhibition constants were still in the range up to 10(-7) M. As Xaa-Thia exist as two isomers, we investigated isomer specific inhibition with regard to DP IV. Thus, our studies have revealed that DP IV was only inhibited by the Z isomer of the Xaa-psi[CS-N]-Thia. For the first time, Xaa-Pyrr and Xaa-Thia were characterized as inhibitors of DP II with inhibition constants in the micromolar range. In contrast to DP IV inhibition, the Xaa-psi[CS-N]-Pyrr and Xaa-psi[CS-N]-Thia have proven to be more potent inhibitors of DP II than the corresponding Xaa-Pyrr and Xaa-Thia. Thus, these Xaa-psi[CS-N]-Thia are new potent inhibitors especially suitable for DP II with K(i) values ranging in the upper nanomolar concentration.


Asunto(s)
Dipeptidil Peptidasa 4/metabolismo , Prolina/metabolismo , Inhibidores de Proteasas/farmacología , Pirroles/farmacología , Tiazoles/farmacología , Aminoácidos/química , Animales , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía de Resonancia Magnética , Inhibidores de Proteasas/química , Pirroles/química , Especificidad por Sustrato , Porcinos , Tiazoles/química
20.
Ceska Slov Farm ; 49(1): 26-8, 2000 Jan.
Artículo en Eslovaco | MEDLINE | ID: mdl-10953438

RESUMEN

The present paper aims to inform the pharmaceutical public about anthracenons and their natural producers. The first available mention dates from 1888 and the present authors also describe their synthesis and use in clinical practice.


Asunto(s)
Antracenos/química , Extractos Vegetales , Animales , Antracenos/uso terapéutico , Antracenos/toxicidad , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/uso terapéutico , Humanos , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad
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