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1.
J Headache Pain ; 19(1): 75, 2018 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-30167989

RESUMEN

BACKGROUND: Familial hemiplegic migraine type 1 (FHM1) is a form of migraine with aura caused by heterozygous mutations in 4 genes: CACNA1A, ATP1A2, SNC1A and PRRT2, but further heterogeneity is expected. Here have been described clinical and molecular features in patients suffering from migraine with Aura (MA), without (MO) and hemiplegic migraine attacks. Next Generation Sequencing by TruSeq Custom Amplicon for CACNA1A and ATP1A2 gene has been performed. All genetic variants have been confirmed by Sanger sequencing and all samples were also analyzed with MLPA assay for ATP1A2-CACNA1A genes to detect duplication or deletion. All MLPA data were verified by Real Time PCR. RESULTS: Sequencing analysis showed 3 point mutations, two novel variants and one already described in literature. Moreover, MLPA analysis showed 3 deletions in 9 sporadic hemiplegic migraine (18%), in 3 patients with non-hemiplegic migraine (4.1%) and in 3 patients affected by episodic ataxia (20%). Two sporadic patients showed a deletion in exons 41-43, while the rest of HM patients (5) showed a deletion in the terminal part of the CACNA1A gene. About episodic ataxia, we have identified deletions in exon 12-15 and in exon 47. Finally, in migraine patients, we have found different subjects affected by different phenotypes deleted in exon 47. CONCLUSION: This work highlights the importance to complement analysis as direct sequencing with quantitative analysis (MLPA). In fact, intragenic CACNA1A rearrangements have been detected. Our work demonstrated that deletions in CACNA1A gene may be associated also to different migraine phenotypes.


Asunto(s)
Canales de Calcio/genética , Deleción Cromosómica , Trastornos Migrañosos/genética , Fenotipo , Adulto , Análisis Mutacional de ADN , Exones/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación Puntual , Análisis de Secuencia de ADN
2.
Biol Direct ; 18(1): 57, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37705059

RESUMEN

BACKGROUND: Spinal muscular atrophy (SMA) is a rare autosomal-recessive neurodegenerative disorder caused by mutations in survival motor neuron 1 (SMN1) gene, and consequent loss of function of SMN protein, which results in progressive loss of lower motor neurons, and muscular wasting. Antisense oligonucleotide (ASO) nusinersen (Spinraza®) modulates the pre-mRNA splicing of the SMN2 gene, allowing rebalance of biologically active SMN. It is administered intrathecally via lumbar puncture after removing an equal amount of cerebrospinal fluid (CSF). Its effect was proven beneficial and approved since 2017 for SMA treatment. Given the direct effect of nusinersen on RNA metabolism, the aim of this project was to evaluate cell-free RNA (cfRNA) in CSF of SMA patients under ASOs treatment for biomarker discovery. METHODS: By RNA-sequencing approach, RNA obtained from CSF of pediatric SMA type 2 and 3 patients was processed after 6 months of nusinersen treatment, at fifth intrathecal injection (T6), and compared to baseline (T0). RESULTS: We observed the deregulation of cfRNAs in patients at T6 and we were able to classify these RNAs into disease specific, treatment specific and treatment dependent. Moreover, we subdivided patients into "homogeneous" and "heterogeneous" according to their gene expression pattern. The "heterogeneous" group showed peculiar activation of genes coding for ribosomal components, meaning that in these patients a different molecular effect of nusinersen is observable, even if this specific molecular response was not referable to a clinical pattern. CONCLUSIONS: This study provides preliminary insights into modulation of gene expression dependent on nusinersen treatment and lays the foundation for biomarkers discovery.


Asunto(s)
Atrofia Muscular Espinal , ARN , Humanos , Niño , Atrofia Muscular Espinal/tratamiento farmacológico , Atrofia Muscular Espinal/genética , Oligonucleótidos/uso terapéutico , Mutación
3.
Chem Res Toxicol ; 25(1): 101-12, 2012 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-22029407

RESUMEN

Accumulation of amyloid-beta (Aß) is one of the hallmarks of Alzheimer's disease (AD), and efficient clearance of Aß by cells of the innate immune system may be an important mechanism for controlling or preventing disease onset. It was reported that peripheral blood mononuclear cells (PBMCs) of most AD patients are defective in the phagocytosis of soluble Aß. Natural curcumins were shown to restore Aß phagocytosis by AD PBMCs and to up-regulate the expression of key genes including MGAT3 and those encoding Toll-like receptors (TLRs). Bisdemethoxycurcumin (BDC), a minor component of natural curcumin, was shown to have the greatest potency for stimulating AD PBMCs. Because natural curcumins have inherent limitations with regard to physicochemical properties, synthetic curcumin analogues were developed that showed improved solubility, stability, and bioavailability. An in vitro system using human monocytic cell lines (U-937, THP-1) was used to evaluate analogues for the potency of innate immune cell stimulation. These cell lines showed responses to curcuminoids and to 1α,25-dihydroxyvitamin D3 (VD3) resembling those seen in human PBMCs. From more than 45 curcuminoids analyzed, the most potent compounds possessing enhanced pharmaceutical properties were identified. The most promising candidates included prodrug versions containing water solubility-enhancing amino acids and stability-increasing modifications near the central diketone. In vivo studies showed compound (5) substantially increased bioavailability by combining several promising structural modifications. Studies examining ex vivo phagocytosis of Aß and bead particles in mouse microglia showed that BDC and several water-soluble analogues were quite effective compared to curcumin or an unnatural analogue. In vitro studies using monocytic cell lines reported herein complement those using human PBMCs and represent a routinely accessible and uniform cellular resource allowing direct comparisons between compounds.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Curcumina/análogos & derivados , Curcumina/farmacología , Expresión Génica/efectos de los fármacos , Microglía/efectos de los fármacos , Monocitos/efectos de los fármacos , Animales , Transporte Biológico/efectos de los fármacos , Línea Celular , Células Cultivadas , Curcumina/farmacocinética , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA , Microglía/metabolismo , Monocitos/metabolismo , Fagocitosis/efectos de los fármacos , ARN Mensajero/metabolismo , Relación Estructura-Actividad
5.
Neurodegener Dis ; 10(1-4): 274-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22156608

RESUMEN

Neurodegenerative diseases are associated with accumulation of modified proteins or peptides including amyloid-ß (Aß) in Alzheimer's disease (AD), and misfolded superoxide dismutase-1 (SOD-1) in amyotrophic lateral sclerosis (ALS). Clearance of Aß or SOD-1 by the innate immune system may be important for controlling or preventing disease onset. Curcumins restore Aß phagocytosis by peripheral blood mononuclear cells (PBMCs) from AD patients and Aß clearance with upregulation of key genes including MGAT3, vitamin D receptor (VDR) and Toll-like receptors (TLRs). Certain curcumins inhibit inflammatory processes of PBMCs from ALS patients. We developed an in vitro system using human monocytes from patients and monocytic cell lines (i.e. U-937, THP-1) for evaluating curcuminoid potency of innate immune cell stimulation. Bisdemethoxycurcumin and certain analogs potentiated MGAT3,VDR and TLR gene expression 3- to 300-fold in U-937 cells. The effect of curcumins on inflammation in monocytes from patients with ALS was examined. Recursive medicinal chemistry was applied to identify compounds that stimulate the innate immune system for use in the clearance of Aß in AD and the reversal of neuroinflammation and defective SOD-1 accumulation in ALS.


Asunto(s)
Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Esclerosis Amiotrófica Lateral/patología , Antiinflamatorios no Esteroideos/farmacología , Curcumina/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Monocitos/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Enfermedad de Alzheimer/metabolismo , Esclerosis Amiotrófica Lateral/metabolismo , Línea Celular Transformada , Células Cultivadas , Curcumina/análogos & derivados , Citocinas/genética , Citocinas/metabolismo , Diarilheptanoides , Humanos , N-Acetilglucosaminiltransferasas/genética , N-Acetilglucosaminiltransferasas/metabolismo , ARN Mensajero/metabolismo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
6.
J Nanosci Nanotechnol ; 11(10): 8804-11, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22400263

RESUMEN

Nanosized platinum-gold alloys clusters have been deposited on gas diffusion electrode by sputter deposition. The deposits were characterized by FE-SEM, TEM and XPS in order to verify the formation of alloy nanoparticles and to study the influence of deposition technique on the nanomorphology. The deposition by sputtering process allowed a uniform distribution of metal particles on porous surface of carbon supports. Typical island growth mode was observed with the formation of a dispersed metal nanoclusters (mean size about 5 nm). Cyclic voltammetry was used to determine the electrochemical active surface and the electrocatalytic performance of the PtAu electrocatalysts for methanol oxidation reaction. The data were re-calculated in the form of mass specific activity (MSA). The sputter-catalyzed electrodes showed higher performance and stability compared to commercial catalysts.

7.
J Nanosci Nanotechnol ; 11(10): 8812-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22400264

RESUMEN

New carbon nanomaterials, i.e., carbon nanotubes and nanofibers, with special physico-chemical properties, are recently studied as support for methanol oxidation reaction electrocatalysts replacing the most widely used carbon black. Particularly, carbon fibrous structures with high surface area and available open edges are thought to be promising. Platelet type carbon nanofibers, which have the graphene layers oriented perpendicularly to the fiber axis, exhibit a high ratio of edge to basal atoms. Different types of carbon nanofibers (tubular and platelet) were grown by plasma enhanced chemical vapour deposition on carbon paper substrates. The process was controlled and optimised in term of growth pressure and temperature. Carbon nanofibers were characterised by high resolution scanning electron microscopy and X-ray photoelectron spectroscopy to assess the morphological properties. Then carbon nanofibers of both morphologies were used as substrates for Pt electrodeposition. High resolution scanning electron microscopy images showed that the Pt nanoparticles distribution was well controlled and the particles size went down to few nanometers. Pt/carbon nanofibers nanocomposites were tested as electrocatalysts for methanol oxidation reaction. Cyclic voltammetry in H2SO4 revealed a catalyst with a high surface area. Cyclic voltammetry in presence of methanol indicated a high electrochemical activity for methanol oxidation reaction and a good long time stability compared to a carbon black supported Pt catalyst.

8.
J Cell Biol ; 63(3): 1074-89, 1974 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4436380

RESUMEN

Numerous small and medium-sized neuronal perikarya in layers III and IV of the visual cortex display an unusual pattern of ribosomal distribution. Instead of being aggregated in clusters, spirals, rows, and other regular polysomal configurations, the ribosomes, whether free or attached to the endoplasmic reticulum, are randomly dispersed, with no discernible pattern. The endoplasmic reticulum in such cells is reduced to a few (perhaps only one) meandering, broad cisternae, which delimit broad fields of cytoplasmic matrix occupied almost solely by scattered, single ribosomes. The Golgi apparatus is elaborate. Mitochondria are either small and numerous or large and infrequent. The other organelles, including the nucleus and nucleolus, are not remarkable. Axonal terminals synapse in the normal fashion on the surfaces of these cells and their dendrites. Associated with these cells are more numerous intermediate cells in which a few to many polysomal clusters can be found. It is proposed that the neurons with dispersed, single ribosomes are inactive in protein synthesis and that the suspension of such an important metabolic activity is probably temporary. Thus, these cells are considered to be part of a population undergoing cyclic fluctuations in the intensity of protein synthesis that should be correlated with their specific neural behavior.


Asunto(s)
Neuronas/ultraestructura , Ribosomas/ultraestructura , Corteza Visual/ultraestructura , Animales , Axones/ultraestructura , Nucléolo Celular/ultraestructura , Núcleo Celular/ultraestructura , Citoplasma/ultraestructura , Retículo Endoplásmico/ultraestructura , Femenino , Aparato de Golgi/ultraestructura , Macaca , Masculino , Microscopía Electrónica , Mitocondrias/ultraestructura , Cuerpos de Nissl/ultraestructura
10.
Hernia ; 11(4): 321-6, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17443270

RESUMEN

PURPOSE: Although at present nonabsorbable meshes are the preferred material for tension-free hernioplasty, some problems with their use have yet to be addressed (i.e., chronic pain and infections). In order to address these disadvantages, a collagen-based material, the porcine small-intestinal submucosa mesh (Surgisis Inguinal Hernia Matrix, Cook Surgical, Bloomington, IN, USA), has recently been developed for hernia repair. METHODS: With the aim of investigating the clinical safety and effectiveness of Surgisis IHM inguinal hernia repair, we report our experience of 45 consecutive hernioplasties with a medium-term follow-up. The surgical technique for the use of this material in hernioplasty is described in detail. RESULTS: Although some local (i.e., seromas) and general (i.e., hyperpyrexia), complications appeared in the immediate postoperative period (all of them disappeared spontaneously), no rejection or infection was observed after operations. At the 2-year follow-up, a low degree of pain and discomfort and no recurrences were observed. CONCLUSIONS: We conclude that the Surgisis IHM hernioplasty is feasible with promising results and, from a clinical perspective, seems safe and effective.


Asunto(s)
Bioprótesis , Hernia Inguinal/cirugía , Mucosa Intestinal/trasplante , Implantación de Prótesis/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Intestino Delgado , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Resultado del Tratamiento
11.
Hernia ; 11(1): 57-60, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17119853

RESUMEN

BACKGROUND: Complicated hernias often involve contaminating surgical procedures in which the use of polypropylene meshes can be hazardous. Prostheses made of porcine dermal collagen (PDC) have recently been proposed as a means to offset the disadvantages of polypropylene meshes and have since been used in humans for hernia repairs. The aim of our study was to evaluate the safety and efficacy of incisional hernia repair using PDC as a mesh in complicated cases involving contamination. METHODS: A prospective study of hernia repair of complicated incisional hernias with contamination using PDC grafts was carried out at the Department of General, Emergency and Transplant Surgery of St Orsola-Malpighi University Hospital. RESULTS: From January 2004 up to the writing of this article, seven patients were treated for complicated incisional hernias with a PDC prosthesis. In six out of seven patients a bowel resection was carried out. There were not surgical complications. Morbidity was 14.2%. No recurrences and wound infections were observed. CONCLUSIONS: Incisional hernioplasty using PDC grafts is a potentially safe and efficient approach in complicated cases with contamination.


Asunto(s)
Colágeno , Hernia Ventral/cirugía , Implantación de Prótesis , Mallas Quirúrgicas , Cavidad Abdominal/microbiología , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos del Sistema Digestivo , Femenino , Estudios de Seguimiento , Hernia Ventral/complicaciones , Hernia Ventral/microbiología , Humanos , Masculino , Estudios Prospectivos , Resultado del Tratamiento
13.
Transplant Proc ; 38(6): 1844-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908301

RESUMEN

The aim of the study was to evaluate the use of Surgisis (Cook Biotech Inc.), a porcine derived extracellular matrix already used in tissue engineering, as a scaffold for neointestinal regeneration in a rat model. A 3-cm length of tubular Surgisis graft was interposed with bilateral anastomoses in the middle of an isolated ileal loop of Sprague Dawley rats with an ileostomy. The grafts were harvested and analyzed using histology and immunohistochemistry at 24 weeks after operation. Macroscopic examination revealed neither stenosis nor adhesions in the area surrounding the neointestine. The regenerated small bowel showed a mean shrinkage of 30.7% (range 20%-40%). Histologic and immunohistochemical evaluation showed a well-developed three layers of mucosa and smooth muscle and serosa in the regenerated bowel wall that were similar to those of the normal bowel with evident neovascularization. Also, the regeneration of smooth muscle fibers and innervation were evident. The preliminary results of this study showed that Surgisis allowed rapid regeneration of mucosa and smooth muscle and therefore may be a promising material for the creation of a neointestine.


Asunto(s)
Intestino Delgado/trasplante , Regiones de Fijación a la Matriz/fisiología , Anastomosis Quirúrgica , Animales , Ileostomía , Íleon/cirugía , Intestino Delgado/fisiología , Masculino , Modelos Animales , Ratas , Ratas Sprague-Dawley , Regeneración , Porcinos , Ingeniería de Tejidos/métodos , Recolección de Tejidos y Órganos/métodos
14.
Curr Top Microbiol Immunol ; 143: 55-69, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2766803

RESUMEN

A progressive development of the application of in situ methodology to ultrastructural procedures has resulted in the ability to detect individual molecules of mRNA with high probability. Beginning with whole-mount cells and then developing myotubes, both in culture and detergent extracted before fixation, we were able to progress to methods which allow detection of mRNA in tissue sections. Initial results confirm that the detection of mRNA in thin-sectioned tissue is very similar to observations on the extracted, cultured cells, and that the same methods of data analysis apply. Current work is devoted to the application of the methodology to other cellular structures, such as the nucleus, and to other tissue-probe systems, such as brain. Acknowledgements. The authors appreciate the skilled help from John McNeil and Shirwin Pockwinse in the laborious and time-consuming preparations of material and photography. FS was on sabbatical leave from the Department of Pathology at Southwestern Medical Center.


Asunto(s)
Sondas de ADN , ARN Mensajero/metabolismo , Animales , Pollos , Microscopía Electrónica , Músculos/metabolismo , Músculos/ultraestructura , Hibridación de Ácido Nucleico
15.
Hernia ; 9(1): 29-31, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15378399

RESUMEN

While polypropylene mesh remains the preferred prosthesis material for hernioplasties, there are some problems with infections, intestinal obstruction and fistulization, and migration particularly in immunodepressed patients. A new degradable and reabsorbable material, the porcine small intestinal submucosa (Surgisis) has been developed for hernia repairs in humans. This prospective study evaluated the safety and efficacy of Lichtenstein hernioplasty using the Surgisis inguinal hernia matrix soft-tissue graft as a mesh in ten immunodepressed subjects. Six subjects were HIV-positive in the immunodepressive phase, and the other four had undergone transplantation (three kidney, one liver). There were no intraoperative or postoperative complications, recurrences, or wound infections. Thus Lichtenstein's hernioplasty using the Surgisis inguinal hernia matrix soft-tissue graft in immunodepressed patients promises safety and efficacy.


Asunto(s)
Implantes Absorbibles , Matriz Extracelular , Seropositividad para VIH/inmunología , Hernia Inguinal/cirugía , Huésped Inmunocomprometido , Implantación de Prótesis/instrumentación , Mallas Quirúrgicas , VIH/inmunología , Seropositividad para VIH/complicaciones , Hernia Inguinal/complicaciones , Humanos , Estudios Prospectivos , Diseño de Prótesis , Seguridad , Resultado del Tratamiento
16.
Stroke ; 32(12): 2854-9, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11739987

RESUMEN

BACKGROUND AND PURPOSE: In response to the need to educate physicians about stroke, we have implemented an educational program on stroke prevention for undergraduate medical students within the first-year neuroscience course. This study investigated whether first-year students learned and retained key information about stroke, and used students' feedback both to identify effective curricular components and to explore their attitudes regarding stroke prevention. METHODS: Stroke knowledge and self-assessed confidence in that knowledge before, immediately after, and 8 months after participation in the stroke curriculum were analyzed and compared for 3 classes, using paired t tests and repeated-measures ANOVA. Student feedback about the effectiveness of specific parts of the curriculum and about the importance of stroke prevention was solicited and evaluated. RESULTS: First-year medical students in 3 classes more than doubled their overall stroke knowledge scores (pretest total mean of 8.2; posttest mean 18.0), and retained significant improvement 8 months later (mean 15.7). Subscores in all 4 areas of stroke knowledge tested significantly increased (P<0.001). Students' confidence in their knowledge of stroke risk factors and warning signs, as well as in their knowledge itself, increased (P<0.001). Each of the 3 cohorts demonstrated similar improvements. Feedback indicated heightened awareness and interest in stroke prevention, which was maintained after completion of the curriculum. CONCLUSIONS: These results demonstrate that when instruction on stroke prevention is incorporated into the first-year curriculum, students learn and retain key information. Because entire classes of medical students are involved, this type of approach has the potential to reach all future physicians and therefore to meaningfully impact future stroke care.


Asunto(s)
Curriculum/normas , Educación de Pregrado en Medicina/normas , Neurociencias/normas , Facultades de Medicina/normas , Accidente Cerebrovascular/prevención & control , Educación de Pregrado en Medicina/estadística & datos numéricos , Evaluación Educacional/estadística & datos numéricos , Humanos , Neurociencias/educación , Facultades de Medicina/estadística & datos numéricos , Estados Unidos
17.
Curr Med Chem ; 6(12): 1197-212, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10519916

RESUMEN

Bafilomycin A1, a macrolide antibiotic isolated from the fermentation of Streptomyces spp., is a potent and selective inhibitor of vacuolar-type proton translocating ATP-ases (V-ATPases) and was used to study the physiological role of this class of enzymes. An extensive chemical effort on the unusual structure of this macrolide led to the synthesis of significantly different bafilomycin derivatives. None of the new analogues was more potent than the parent compound but provided a significant amount of information about the structural requirements for the inhibitory activity of bafilomycin A1 in particular on chicken osteoclast (cOc) ATPase. The vinylic methoxy group adjacent to a carbonyl function, the dienic system and the hydroxy group at position 7 were recognized to be essential features for bafilomycin V-ATPase-inhibitory activity. This information was utilized to design simplified novel derivatives as inhibitors of bone resorption.


Asunto(s)
Antibacterianos/farmacología , Macrólidos , ATPasas de Translocación de Protón/antagonistas & inhibidores , ATPasas de Translocación de Protón Vacuolares , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Diseño de Fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Concentración 50 Inhibidora , ATPasas de Translocación de Protón/metabolismo , Streptomyces/química , Relación Estructura-Actividad
18.
Curr Pharm Des ; 8(23): 2033-48, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12171517

RESUMEN

The proton pump expressed on the plasma membrane of bone resorbing osteoclasts, and which mediates the acidification of the extracellular environment in resorption lacuna, belongs to the family of vacuolar H(+)-ATPases, which are enzymes ubiquitously distributed among all cells and are evolutionary conserved. These pumps have two functional domains: a peripherally associated cytoplasmatic section, and a proton channel composed of several subunits one of which, the 116 kDa subunit, is expressed exclusively in osteoclasts and confers unique functional and pharmacological properties to the osteoclast V-ATPase. It was demonstrated that inhibition of this pump can abolish bone resorption; therefore, osteoclast-selective inhibitors could provide novel and useful agents for the treatment of osteoporosis. This paper reviews the medicinal chemistry approaches that have allowed to obtain such new agents, most of which have been designed starting from the natural macrolide antibiotic bafilomycin A(1), a potent and selective inhibitor of all V-ATPases. Identification of SAR and of minimal structural requirements for bafilomycin activity have allowed to obtain (2Z,4E)-5-(5,6-dichloroindolyl)-2-methoxy-N-(1,2,2,6,6-pentamethylpiperidin-4-yl)-2,4-pentadienamide (SB-242784) which inhibits the osteoclastic proton pump and bone resorption in vitro. Although it inhibits the activity of non-osteoclastic proton pumps as well, it appears to have reasonable selectivity and its administration for 6 months prevented the loss of femoral and vertebral BMD in ovariectomized rats, without any significant renal effects in control and acid-loaded animals. Other independent approaches that did not start from bafilomycin have led to the discovery of a different class of V-ATPase inhibitors, among which 4-(2,6-dichlorobenzoyl)amino-2-trifluoromethyl(benzoimidazol-1-yl)acetyl morpholine (FR177995) was the most effective in preventing bone resorption in an ovariectomized rat model of osteoporosis. These compounds are of great pharmaceutical and medical interest because they allow to target a specific function of the osteoclast; however, only clinical trials might demonstrate whether they have significant advantages over other inhibitors of bone resorption for the treatment of osteoporosis.


Asunto(s)
Inhibidores Enzimáticos/síntesis química , Osteoclastos/efectos de los fármacos , Osteoclastos/enzimología , ATPasas de Translocación de Protón Vacuolares/antagonistas & inhibidores , Animales , Factores Biológicos/química , Factores Biológicos/aislamiento & purificación , Factores Biológicos/farmacología , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/enzimología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Macrólidos/síntesis química , Macrólidos/química , Macrólidos/farmacología , Osteoporosis/tratamiento farmacológico , Osteoporosis/enzimología , Relación Estructura-Actividad , ATPasas de Translocación de Protón Vacuolares/fisiología
19.
J Med Chem ; 41(11): 1883-93, 1998 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-9599238

RESUMEN

The macrolide antibiotic bafilomycin A1 is a highly potent and selective inhibitor of all the vacuolar ATPases (V-ATPases). With the aim of obtaining novel analogues specific for the osteoclast subclass of vacuolar ATPase, 31 derivatives of bafilomycin A1 were synthesized and tested for their ability to inhibit differentially the V-ATPase-driven proton transport in membrane vesicles derived from chicken osteoclasts (cOc) and bovine chromaffin granules (bCG). Although none of the new analogues were more potent than the parent compound, the obtained data provided a significant amount of information about the structural requirements for the inhibitory activity of bafilomycin A1. The different effects of a few analogues on the two enzymes could also suggest the possibility of a selective modulation of the V-ATPases in different tissues.


Asunto(s)
Antibacterianos/farmacología , Inhibidores Enzimáticos , Macrólidos , ATPasas de Translocación de Protón/antagonistas & inhibidores , Vacuolas/enzimología , Adenosina Trifosfato/metabolismo , Médula Suprarrenal/efectos de los fármacos , Médula Suprarrenal/enzimología , Animales , Antibacterianos/química , Transporte Biológico/efectos de los fármacos , Bovinos , Pollos , Células Cromafines/efectos de los fármacos , Células Cromafines/enzimología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Osteoclastos/efectos de los fármacos , Osteoclastos/enzimología , Bombas de Protones/metabolismo , Ratas , Ratas Wistar , Relación Estructura-Actividad
20.
J Med Chem ; 34(11): 3261-7, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1659637

RESUMEN

The synthesis and oral antihypertensive activity in conscious spontaneously hypertensive rats of two new series of compounds related to the prototype potassium channel activator cromakalim (1) are described. In the first series, replacement of the benzopyran oxygen atom by nitrogen or methylene led to the 1,2,3,4-tetrahydroquinoline 12 and 1,2,3,4-tetrahydronaphthalene 13, which were both less active than 1. However, in contrast to the equivalent activity found previously for 1 and its dehydrated analogue 28, the dihydronaphthalene 27 was found to be more active than 13. In the second series, replacement of the C(4) amide nitrogen atom in acyclic amides related to cromakalim by methylene gave ketone 16 that was less active than the corresponding amide 15. However, replacement of the 4-acetonyl substituent in 16 by N,N-dimethylacetamido as in compound 22 resulted in a marked enhancement in activity. The compounds described in this paper thus illustrate the importance of the benzopyran oxygen and C(4) substituent on antihypertensive activity in the cromakalim series of potassium channel activators.


Asunto(s)
Antihipertensivos/síntesis química , Benzopiranos/síntesis química , Pirroles/síntesis química , Quinolonas/síntesis química , Tetrahidronaftalenos/síntesis química , Administración Oral , Animales , Antihipertensivos/farmacología , Benzopiranos/farmacología , Presión Sanguínea/efectos de los fármacos , Cromakalim , Pirroles/farmacología , Quinolonas/farmacología , Ratas , Ratas Endogámicas SHR , Relación Estructura-Actividad , Tetrahidronaftalenos/farmacología
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