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1.
Osteoarthritis Cartilage ; 28(5): 639-645, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32028022

RESUMEN

OBJECTIVE: To evaluate the anti-inflammatory effects of clinically relevant naproxen sodium (Nx) concentrations on human monocyte-derived macrophages in a controlled in vitro system and human primary synovial fluid (SF) cells. DESIGN: Using phorbol 12-myristate 13-acetate, THP-1 human monocytic cells were differentiated into mature monocyte-derived macrophages in vitro then treated with Nx pre- or post-activating an inflammatory response with lipopolysaccharide (LPS) and hyaluronan (HA) fragments (n = 8/group). Cell culture supernatants were assessed for NF-κB activity and prostaglandin E2 (PGE2), indicating cyclooxygenase enzyme activity. Under Duke IRB approval, primary human SF cells were collected at the time of knee joint replacement (n = 19 individuals) for osteoarthritis (OA), and cultured with LPS, HA and Nx; SF cells were characterized by polychromatic flow cytometry for cell surface markers and intracellular cytokines. RESULT: Compared to placebo treatment of THP-1 cells, low dose Nx (corresponding 27.5-440 mg/L orally) added both pre- and post-activation with LPS/HA, significantly reduced NF-κB activity and PGE2: mean reduction to 73%, 61%, 17% and 10% of placebo, respectively. LPS/HA treatment of primary OA SF cells significantly increased the number of IL-1ß producing primary monocytes and macrophages, and by 24 h the overall production of secreted cytokines (IL-1ß, IL-6, IL8, and TNF-α). Low dose Nx reduced the percentage of IL-1ß producing primary monocytes and macrophages. CONCLUSION: LPS/HA induced inflammation of THP-1 monocytic and primary human SF cells. Low dose Nx both prevented and reduced inflammatory responses of a human monocytic cell line and reduced IL-1ß production by primary human SF monocytes and macrophages.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Citocinas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , Naproxeno/farmacología , Osteoartritis de la Rodilla/inmunología , Citocinas/inmunología , Dinoprostona/inmunología , Citometría de Flujo , Humanos , Ácido Hialurónico , Inflamación/inmunología , Interleucina-1beta/efectos de los fármacos , Interleucina-1beta/inmunología , Interleucina-6/inmunología , Interleucina-8/efectos de los fármacos , Interleucina-8/inmunología , Lipopolisacáridos , Macrófagos/inmunología , Monocitos/inmunología , FN-kappa B/efectos de los fármacos , FN-kappa B/inmunología , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Líquido Sinovial/citología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Células THP-1 , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/inmunología
2.
Anaesthesia ; 72(6): 729-736, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28251606

RESUMEN

Previous pilot work has established an association between obstructive sleep apnoea and the development of acute postoperative delirium , but it remains unclear to what extent this risk factor is modifiable in the 'real world' peri-operative setting. In a single-blind randomised controlled trial, 135 elderly surgical patients at risk for obstructive sleep apnoea were randomly assigned to receive peri-operative continuous positive airway pressure (CPAP) or routine care. Of the 114 patients who completed the study, 21 (18.4%) experienced delirium. Delirium was equally common in both groups: 21% (12 of 58 subjects) in the CPAP group and 16% (9 of 56 subjects) in the routine care group (OR = 1.36 [95%CI 0.52-3.54], p = 0.53). Delirious subjects were slightly older - mean (SD) age 68.9 (10.7) vs. 64.9 (8.2), p = 0.07 - but had nearly identical pre-operative STOP-Bang scores (4.19 (1.1) versus 4.27 (1.3), p = 0.79). Subjects in the CPAP group used their devices for a median (IQR [range]) of 3 (0.25-5 [0-12]) nights pre-operatively (2.9 (0.1-4.8 [0.0-12.7]) hours per night) and 1 (0-2 [0-2]) nights postoperatively (1.4 (0.0-5.1 [0.0-11.6]) hours per night). Among the CPAP subjects, the residual pre-operative apnoea-hypopnea index had a significant effect on delirium severity (p = 0.0002). Although we confirm that apnoea is associated with postoperative delirium, we did not find that providing a short-course of auto-titrating CPAP affected its likelihood or severity. Voluntary adherence to CPAP is particularly poor during the initiation of therapy.


Asunto(s)
Anestesia de Conducción/métodos , Anestesia General/métodos , Artroplastia de Reemplazo/métodos , Presión de las Vías Aéreas Positiva Contínua/métodos , Delirio del Despertar/terapia , Atención Perioperativa/métodos , Complicaciones Posoperatorias/terapia , Apnea Obstructiva del Sueño/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Estudios Prospectivos , Método Simple Ciego
3.
Osteoarthritis Cartilage ; 24(2): 374-81, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26417696

RESUMEN

OBJECTIVE: We investigated tissue turnover in healthy and osteoarthritic cartilage. We challenge long held views that osteoarthritis (OA) is dominated by a similar turnover process in all joints and present evidence that hip and knee cartilage respond very differently to OA. METHODS: d- and l-Aspartate (Asp) were quantified for whole cartilage, collagen and non-collagenous components of cartilage obtained at the time of joint replacement. We computed the Asp racemization ratio (Asp-RR = d/d + l Asp), reflecting the proportion of old to total protein, for each component. RESULTS: Compared with hip OA, knee OA collagen fibrils (P < 0.0001), collagen (P = 0.007), and non-collagenous proteins (P = 0.0003) had significantly lower age-adjusted mean Asp-RRs consistent with elevated protein synthesis in knee OA. Knee OA collagen had a mean hydroxyproline/proline (H/P) ratio of 1.2 consistent with the presence of type III collagen whereas hip OA collagen had a mean H/P ratio of 0.99 consistent with type II collagen. Based on Asp-RR, the relative age was significantly different in knee and hip OA (P < 0.0005); on average OA knees were estimated to be 30 yrs 'younger', and OA hips 10 yrs 'older' than non-OA. CONCLUSIONS: The metabolic response to OA was strikingly different by joint site. Knee OA cartilage evinced an anabolic response that appeared to be absent in hip OA cartilage. These results challenge the long held view that OA cartilage is capable of only minimal repair and that collagen loss is irreversible.


Asunto(s)
Ácido Aspártico/metabolismo , Cartílago Articular/metabolismo , Ácido D-Aspártico/metabolismo , Osteoartritis de la Cadera/metabolismo , Osteoartritis de la Rodilla/metabolismo , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Colágeno/metabolismo , Colágeno Tipo II/metabolismo , Colágeno Tipo III/metabolismo , Femenino , Humanos , Hidroxiprolina/metabolismo , Masculino , Persona de Mediana Edad , Prolina/metabolismo , Adulto Joven
4.
J Ultrasound ; 18(3): 229-35, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26261465

RESUMEN

ABSTRACT: Cardiorenal syndrome type 1 (CRS-1) is the acute kidney disfunction caused by an acute worsening of cardiac function. CRS-1 is the consequence of renal vasoconstriction secondary to renin-angiotensin system (RAS) activation. No animal models of CRS-1 are described in literature. PURPOSE: To characterize a murine model of CRS-1 by using a high-resolution ultrasound echo-color Doppler system (VEVO2100). MATERIALS: Post-ischemic heart failure was induced by coronary artery ligation (LAD) in seven CD1 mice. Fifteen and thirty days after surgery, mice underwent cardiac and renal echo-color Doppler. Serum creatinine and plasma renin activity were measured after killing. Animals were compared to seven CD1 control mice. RESULTS: Heart failure with left ventricle dilatation (end diastolic area, p < 0.05 vs. controls) and significantly reduced ejection fraction (EF; p < 0.01 vs. controls) was evident 15 days after LAD. We measured a significant renal vasoconstriction in infarcted mice characterized by increased renal pulsatility index (PI; p < 0.05 vs. controls) associated to increased creatinine and renin levels (p < 0.05 vs. controls). CONCLUSIONS: The mice model of LAD is a good model of CRS-1 evaluable by Doppler sonography and characterized by renal vasoconstriction due to the activation of the renin-angiotensin system secondary to heart failure.

5.
Curr Med Chem ; 20(13): 1639-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23410164

RESUMEN

Polypharmacology offers a model for the way drug discovery must evolve to develop therapies most suited to treating currently incurable diseases. It is driven by a worldwide demand for safer, more effective, and affordable medicines against the most complex diseases, and by the failures of modern drug discovery to provide these. Polypharmacology can involve combinations and/or multitarget drugs (MTD). Although not mutually exclusive, my premise is that MTDs have inherent advantages over combinations. This review article focuses on MTDs from a medicinal chemistry perspective. I will explore their use in current clinical practice, their likely application in the future, and the challenges to be overcome to achieve this goal.


Asunto(s)
Combinación de Medicamentos , Descubrimiento de Drogas/métodos , Preparaciones Farmacéuticas/administración & dosificación , Animales , Farmacorresistencia Microbiana , Humanos , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/economía
6.
Osteoarthritis Cartilage ; 20(5): 440-445, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22353746

RESUMEN

OBJECTIVE: Selenium neutralizes interleukin-1ß (IL-1ß) induced inflammatory responses in chondrocytes. We investigated potential mechanisms for this through in vitro knock down of three major selenoproteins, Iodothyronine Deiodinase-2 (DIO2), Glutathione Peroxidase-1 (GPX1), and Thioredoxin Reductase-1 (TR1) in primary human chondrocytes. METHODS: Primary human chondrocytes were transfected with scrambled small interfering ribonucleic acid (siRNA) or siRNA specific for DIO2, GPX1 and TR1. After 48 h, transfected cells were cultured in serum free media for 48 h, with or without 10 pg/ml IL-1ß for the final 24h. The efficiency of siRNAs was confirmed by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot analysis. The gene expression, by qRT-PCR, of cyclooxygenase-2 (COX2), IL-1ß, and Liver X receptor (LXR) alpha and beta was evaluated to determine the impact of selenoprotein knockdown on inflammatory responses in chondrocytes. RESULTS: The messenger RNA (mRNA) expression of DIO2, GPX1, and TR1 was significantly decreased by the specific siRNAs (reduced 56%, P=0.0004; 96%, P<0.0001; and 66%, P<0.0001, respectively). Suppression of DIO2, but not GPX1 or TR1, significantly increased (~2-fold) both basal (P=0.0005) and IL-1ß induced (P<0.0001) COX2 gene expression. Similarly, suppression of DIO2 significantly increased (∼9-fold) IL-1ß induced IL-1ß gene expression (P=0.0056) and resulted in a 32% (P=0.0044) decrease in LXRα gene expression but no effect on LXRß. CONCLUSIONS: Suppression of the selenoprotein DIO2 resulted in strong pro-inflammatory effects with increased expression of inflammatory mediators, IL-1ß and COX2, and decreased expression of LXRα suggesting that this may be the upstream target through which the anti-inflammatory effects of DIO2 are mediated.


Asunto(s)
Condrocitos/metabolismo , Mediadores de Inflamación/metabolismo , Yoduro Peroxidasa/fisiología , Células Cultivadas , Ciclooxigenasa 2/biosíntesis , Ciclooxigenasa 2/genética , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/fisiología , Humanos , Interleucina-1beta/biosíntesis , Interleucina-1beta/genética , Yoduro Peroxidasa/genética , Receptores X del Hígado , Receptores Nucleares Huérfanos/biosíntesis , Receptores Nucleares Huérfanos/genética , ARN Interferente Pequeño/genética , Tiorredoxina Reductasa 1/genética , Tiorredoxina Reductasa 1/fisiología , Transfección , Glutatión Peroxidasa GPX1 , Yodotironina Deyodinasa Tipo II
7.
Neuropharmacology ; 62(2): 997-1003, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22032870

RESUMEN

Alzheimer's disease (AD) is the most common cause of dementia, clinically characterized by loss of memory and progressive deficits in different cognitive domains. An emerging disease-modifying approach to face the multifactorial nature of AD may be represented by the development of Multi-Target Directed Ligands (MTDLs), i.e., single compounds which may simultaneously modulate different targets involved in the neurodegenerative AD cascade. The structure of tacrine, an acetylcholinesterase (AChE) inhibitor (AChEI), has been widely used as scaffold to provide new MTDLs. In particular, its homodimer bis(7)tacrine represents an interesting lead compound to design novel MTDLs. Thus, in the search of new rationally designed MTDLs against AD, we replaced the heptamethylene linker of bis(7)tacrine with the structure of cystamine, leading to cystamine-tacrine dimer. In this study we demonstrated that the cystamine-tacrine dimer is endowed with a lower toxicity in comparison to bis(7)tacrine, it is able to inhibit AChE, butyrylcholinesterase (BChE), self- and AChE-induced beta-amyloid aggregation in the same range of the reference compound and exerts a neuroprotective action on SH-SY5Y cell line against H(2)O(2)-induced oxidative injury. The investigation of the mechanism of neuroprotection showed that the cystamine-tacrine dimer acts by activating kinase 1 and 2 (ERK1/2) and Akt/protein kinase B (PKB) pathways. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Cistamina/química , Diseño de Fármacos , Tacrina/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/uso terapéutico , Cistamina/farmacología , Cistamina/uso terapéutico , Combinación de Medicamentos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tacrina/farmacología , Tacrina/uso terapéutico
8.
Osteoarthritis Cartilage ; 20(1): 64-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22063369

RESUMEN

Osteoarthritis (OA) is a debilitating disease associated with pain and loss of function in numerous diarthrodial joints of the body. Assessments of the severity and/or progression of OA are commonly based on radiographic stages and pain level, which aren't always correlated to severity of disease or joint dysfunction and may be confounded by other factors(1). There has been recent interest in identifying a biochemical signature of OA(1) that may be detected in serum, urine, and/or synovial fluid that would represent repeatable and predictable biomarkers of OA onset and/or progression. The objective of this study was to use global metabolic profiling to identify a distinct metabolic profile for cultured human synovial tissue from patients with end-stage OA compared to patients with little or no evidence of disease. While metabolic profiles from cultured tissues are not expected to reproduce in vivo profiles, it is expected that perturbations in metabolism caused by end-stage disease would result in differences in metabolic profiles in vitro compared to tissue with little or no evidence of disease. Because metabolomic perturbations often occur prior to alterations in the genome or proteome, metabolomic analysis possibly provides an earlier window to an altered biochemical profile for OA onset and/or progression, and may provide a unique set of potential drug targets. The synovium was targeted because it has been implicated in OA as a mediator of disease progression; osteoarthritic synovium has been demonstrated to express pro-inflammatory cytokines, such as Tumor Necrosis Factor - α (TNF-α), Interleukin-1 ß (IL-1ß), and IL-6(2), suggesting that a diseased synovial lining could produce an ideal set of biomarkers for diagnosing OA and/or monitoring disease progression. Media from the culture of synovial explants dissected from diseased human joints (early or end-stage OA) was subjected to global metabolic profiling with a liquid chromatography (LC)/and gas chromatography (GC)/mass spectrophotometry (MS)-based technology platform. Metabolites were identified by automated comparison of the ion features in the experimental samples to a reference library of chemical standard entries developed at Metabolon, Inc (Durham, NC). Global metabolic profiling resulted in the identification of 105 distinct compounds across all sample groups, with 11 compounds showing significantly different relative concentrations between end-stage and no/early disease groups. Metabolites specific to collagen metabolism, branched-chain amino acid metabolism, energy metabolism and tryptophan metabolism were amongst the most significant compounds, suggesting an altered metabolic state with disease progression.


Asunto(s)
Metaboloma/fisiología , Osteoartritis/metabolismo , Membrana Sinovial/metabolismo , Biomarcadores/metabolismo , Medios de Cultivo Condicionados , Progresión de la Enfermedad , Humanos , Osteoartritis/diagnóstico , Técnicas de Cultivo de Tejidos
9.
Osteoarthritis Cartilage ; 19(1): 118-25, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21035557

RESUMEN

OBJECTIVE: Several lines of evidence show that selenium (Se) has potential protective effects in osteoarthritis (OA), however the exact mechanism is still unclear. As interleukin-1ß (IL-1ß) is one of the key proinflammatory cytokines contributing to the progression in OA, we investigated the effect of Se in neutralizing the inflammatory effects of IL-1ß on nitric oxide (NO) and prostaglandin E2 (PGE2) production, and the signaling pathways involved. METHODS: Isolated primary human chondrocytes were pretreated with selenomethionine (SeMet) (0.5 µM SeMet) for 24 h then co-treated without or with IL-1ß (10 pg/ml or 50 pg/ml) for another 24 h followed by RNA isolation. Gene expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) was determined by quantitative Real Time-Polymerase Chain Reaction. Culture media concentrations of NO and PGE2 were determined by nitrite (NO2⁻) assay and immunoassay respectively. For analysis of cell signaling pathways, chondrocytes were pretreated with SeMet then stimulated with IL-1ß for 0-45 min. The activity of IL-1ß signaling pathways was determined by Western blot screening of phosphorylation states of signal transduction proteins. RESULTS: SeMet inhibited chondrocyte gene expression of IL-1ß induced iNOS (31-54%, P=0.031) and COX2 (50-65%, P=0.031) with corresponding reductions in both NO (19-47%, P=0.031) and PGE2 (24-32%, P=0.031) production. Pretreatment with SeMet attenuated IL-1ß induced activation of p38 MAPK (39%, P=0.039) but not the extracellular signal-regulated kinase pathways (ERK) 1/2, c-Jun N-terminal kinases (JNK) or nuclear factor κB (NFκB). CONCLUSIONS: This study elucidates one potential protective mechanism of Se, namely through the alteration of cell signaling and downstream transcription of pro-inflammatory effects of IL-1ß.


Asunto(s)
Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Ciclooxigenasa 2/metabolismo , Interleucina-1beta/antagonistas & inhibidores , Interleucina-1beta/farmacología , Óxido Nítrico Sintasa/metabolismo , Selenometionina/farmacología , Anciano , Western Blotting , Células Cultivadas/efectos de los fármacos , Células Cultivadas/metabolismo , Dinoprostona/metabolismo , Humanos , Persona de Mediana Edad , ARN Mensajero/metabolismo
10.
Br J Cancer ; 102(12): 1707-16, 2010 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-20461078

RESUMEN

BACKGROUND: XIAP (X-linked inhibitor of apoptosis protein) is an anti-apoptotic protein exerting its activity by binding and suppressing caspases. As XIAP is overexpressed in several tumours, in which it apparently contributes to chemoresistance, and because its activity in vivo is antagonised by second mitochondria-derived activator of caspase (SMAC)/direct inhibitor of apoptosis-binding protein with low pI, small molecules mimicking SMAC (so called SMAC-mimetics) can potentially overcome tumour resistance by promoting apoptosis. METHODS: Three homodimeric compounds were synthesised tethering a monomeric SMAC-mimetic with different linkers and their affinity binding for the baculoviral inhibitor repeats domains of XIAP measured by fluorescent polarisation assay. The apoptotic activity of these molecules, alone or in combination with tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) and/or Bortezomib, was tested in melanoma cell lines by MTT viability assays and western blot analysis of activated caspases. RESULTS: We show that in melanoma cell lines, which are typically resistant to chemotherapeutic agents, XIAP knock-down sensitises cells to TRAIL treatment in vitro, also favouring the accumulation of cleaved caspase-8. We also describe a new series of 4-substituted azabicyclo[5.3.0]alkane monomeric and dimeric SMAC-mimetics that target various members of the IAP family and powerfully synergise at submicromolar concentrations with TRAIL in inducing cell death. Finally, we show that the simultaneous administration of newly developed SMAC-mimetics with Bortezomib potently triggers apoptosis in a melanoma cell line resistant to the combined effect of SMAC-mimetics and TRAIL. CONCLUSION: Hence, the newly developed SMAC-mimetics effectively synergise with TRAIL and Bortezomib in inducing cell death. These findings warrant further preclinical studies in vivo to verify the anticancer effectiveness of the combination of these agents.


Asunto(s)
Ácidos Borónicos/farmacología , Muerte Celular/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/farmacología , Melanoma/tratamiento farmacológico , Proteínas Mitocondriales/farmacología , Pirazinas/farmacología , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Proteínas Reguladoras de la Apoptosis , Bortezomib , Caspasa 8/metabolismo , Línea Celular Tumoral , Regulación hacia Abajo , Interacciones Farmacológicas , Sinergismo Farmacológico , Técnicas de Silenciamiento del Gen , Humanos , Péptidos y Proteínas de Señalización Intracelular/administración & dosificación , Proteínas Mitocondriales/administración & dosificación , Ligando Inductor de Apoptosis Relacionado con TNF/administración & dosificación
11.
Curr Med Chem ; 17(17): 1825-38, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20345341

RESUMEN

To date, the pharmacotherapy of Alzheimer's disease (AD) has relied on acetylcholinesterase (AChE) inhibitors (AChEIs) and, more recently, an N-methyl-D-aspartate receptor (NMDAR) antagonist. AD is a multifactorial syndrome with several target proteins contributing to its etiology. "Multi-target-directed ligands" (MTDLs) have great potential for treating complex diseases such as AD because they can interact with multiple targets. The design of compounds that can hit more than one specific AD target thus represents an innovative strategy for AD treatment. Tacrine was the first AChEI introduced in therapy. Recent studies have demonstrated its ability to interact with different AD targets. Furthermore, numerous tacrine homo- and heterodimers have been developed with the aim of improving and enlarging its biological profile beyond its ability to act as an AChEI. Several tacrine hybrid derivatives have been designed and synthesized with the same goal. This review will focus on and summarize the last two years of research into the development of tacrine derivatives able to hit AD targets beyond simple AChE inhibition.


Asunto(s)
Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/farmacología , Tacrina/análogos & derivados , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Inhibidores de la Colinesterasa/uso terapéutico , Humanos , Modelos Moleculares , Relación Estructura-Actividad , Tacrina/farmacología , Tacrina/uso terapéutico
12.
Curr Pharm Des ; 15(6): 601-13, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19199985

RESUMEN

The multifunctional nature of Alzheimer's disease (AD) provides the logical foundation for the development of an innovative drug design strategy centered on multi-target-directed-ligands (MTDLs). In recent years, the MTDL concept has been exploited to design different ligands hitting different biological targets. Our first rationally designed MTDL was the polyamine caproctamine (1), which provided a synergistic cholinergic action against AD by antagonizing muscarinic M(2) autoreceptors and inhibiting acetylcholinesterase (AChE). Lipocrine (7) represented the next step in our research. Due to its ability to inhibit AChE catalytic and non-catalytic functions together with oxidative stress, 7 emerged as an interesting pharmacological tool for investigating the neurodegenerative mechanism underlying AD. Memoquin (9) is a quinone-bearing polyamine endowed with a unique multifunctional profile. With its development, we arrived at the proof of concept of the MTDL drug discovery approach. Experiments in vitro and in vivo confirmed its multimodal mechanisms of action and its interaction with different end-points of the neurotoxic cascade leading to AD. More recently, the MTDL approach led to carbacrine (12). In addition to the multiple activities displayed by 7, 12 displayed an interesting modulation of NMDA receptor activity. The pivotal role played by this target in AD pathogenesis suggests that 12 may be a promising new chemical entity in the MTDL gold rush.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Diseño de Fármacos , Alcanos/farmacología , Alcanos/uso terapéutico , Enfermedad de Alzheimer/fisiopatología , Animales , Carbazoles/farmacología , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/uso terapéutico , Etilaminas/farmacología , Etilaminas/uso terapéutico , Humanos , Ligandos , Tacrina/análogos & derivados , Tacrina/farmacología , Ácido Tióctico/análogos & derivados , Ácido Tióctico/farmacología
13.
J Ultrasound ; 12(1): 1-5, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23396636

RESUMEN

AIM: To evaluate the prevalence, severity, and hemodynamic features of nonalcoholic fatty liver disease (NAFLD) in nonobese diabetics. METHODS: We studied 100 consecutive nonobese (body mass index [BMI] < 30) patients with type 1 (n = 17) or type 2 (n = 83) diabetes and no known causes of liver disease. Steatosis was diagnosed and graded with ultrasonography. Digital sonographic images of the liver and right kidney were analyzed with dedicated software (HDI-Lab), and the liver/kidney ratio of grey-scale intensity was calculated as an index of the severity of the steatosis. Severity scores ranging from 0 (none) to 5 (severe) were compared with sonographic and Doppler findings (right liver size, portal vein diameter and flow velocity, hepatic and splenic arterial pulsatility indices, hepatic-vein flow profile and A- and S-wave velocities). RESULTS: The prevalence of steatosis was 24% in type I and 80% in type II diabetes (grade 1 in 17%, grade 2 in 34%, grade 3 in 33%, grade 4 in 9%, grade 5 in 7%). In patients with steatosis (especially those with grades 4-5 disease), hepatic volume was increased (p < 0.005). Portal vein diameter was increased in grade 5 steatosis. The hepatic artery pulsatility index was significantly increased, particularly in grades 4 and 5 (p < 0.0001); portal and A-wave velocities were significantly reduced in grades 3-5 (p < 0.001); and the hepatic vein flow profile was altered in 27% (biphasic: 20%, flat: 7%) patients with steatosis, although there was no correlation with severity. CONCLUSIONS: NAFLD is very frequent in nonobese diabetics with type 2 but not type 1 disease, and it is associated with hepatomegaly and liver hemodynamic alterations only when it is severe.

14.
Antiviral Res ; 78(1): 37-46, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18083241

RESUMEN

Life-threatening RNA viruses emerge regularly, and often in an unpredictable manner. Yet, the very few drugs available against known RNA viruses have sometimes required decades of research for development. Can we generate preparedness for outbreaks of the, as yet, unknown viruses? The VIZIER (VIral enZymes InvolvEd in Replication) (http://www.vizier-europe.org/) project has been set-up to develop the scientific foundations for countering this challenge to society. VIZIER studies the most conserved viral enzymes (that of the replication machinery, or replicases) that constitute attractive targets for drug-design. The aim of VIZIER is to determine as many replicase crystal structures as possible from a carefully selected list of viruses in order to comprehensively cover the diversity of the RNA virus universe, and generate critical knowledge that could be efficiently utilized to jump-start research on any emerging RNA virus. VIZIER is a multidisciplinary project involving (i) bioinformatics to define functional domains, (ii) viral genomics to increase the number of characterized viral genomes and prepare defined targets, (iii) proteomics to express, purify, and characterize targets, (iv) structural biology to solve their crystal structures, and (v) pre-lead discovery to propose active scaffolds of antiviral molecules.


Asunto(s)
Antivirales/farmacología , Biología Computacional , Cristalografía , Diseño de Fármacos , Genómica , Proteómica , Virus ARN/efectos de los fármacos , ARN Polimerasa Dependiente del ARN , Replicación Viral/efectos de los fármacos , Antivirales/química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Cooperación Internacional , Modelos Moleculares , Virus ARN/enzimología , Virus ARN/patogenicidad , Virus ARN/fisiología , ARN Viral/biosíntesis , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , ARN Polimerasa Dependiente del ARN/química , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo
15.
Biochem Biophys Res Commun ; 354(2): 409-13, 2007 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-17227671

RESUMEN

The use of agents targeting EGFR represents a new frontier in colon cancer therapy. Among these, mAbs and EGFR tyrosine kinase inhibitors seemed to be the most promising. However they have demonstrated scarce utility in therapy, the former being effective only at toxic doses, the latter resulting inefficient in colon cancer. This paper presents studies on a new EGFR inhibitor, FR18, a molecule containing the same naphthoquinone core as shikonin, an agent with great anti-tumor potential. In HT29, a human colon carcinoma cell line, flow cytometry, immunoprecipitation, and Western blot analysis, confocal spectral microscopy have demonstrated that FR18 is active at concentrations as low as 10 nM, inhibits EGF binding to EGFR while leaving unperturbed the receptor kinase activity. At concentration ranging from 30 nM to 5 microM, it activates apoptosis. FR18 seems therefore to have possible therapeutic applications in colon cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Receptores ErbB/antagonistas & inhibidores , Naftoquinonas/química , Inhibidores de Proteínas Quinasas/química , Neoplasias del Colon/enzimología , Relación Dosis-Respuesta a Droga , Receptores ErbB/metabolismo , Células HT29 , Humanos , Microscopía Confocal , Naftoquinonas/farmacología , Inhibidores de Proteínas Quinasas/farmacología
16.
Phytopathology ; 97(3): 352-8, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18943656

RESUMEN

ABSTRACT The dynamics of the inoculum of Taphrina deformans were studied during a 4-year period by (i) inspecting curled leaves for the presence of asci, (ii) placing deposition spore samplers within the tree canopies, and (iii) exposing potted peach plants (trap plants). These three approaches produced consistent results. Four main periods characterized the dynamics of the inoculum: the first period coincides with the parasitic stage of the pathogen's life cycle and the other periods with the saprophytic stage. Mid- to late spring (first period) was characterized by the presence of asci on infected leaves which produced and ejected large quantities of ascospores in 96% of the samplings. Rainfall was not necessary for ascospore dispersal, which was favored by air temperature <20 degrees C and relative humidity >/=80% or wetness duration >8 h. In summer and autumn (second period), blastospores were trapped in 54 and 24% of samplings, respectively, with low spore numbers. In the winter (third period), blasto-spores were trapped in the lowest numbers and in only 6% of samplings. In late winter to early spring (fourth period), blastospores were found in 56% of samples, with increasing numbers. Rainfall significantly influenced blastospore dispersal and temperature was correlated with the seasonality found during the saprophytic stage.

17.
Phytopathology ; 97(12): 1625-33, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18943723

RESUMEN

ABSTRACT The effect of environment on the infection of peach fruit by Taphrina deformans was investigated using orchard observations under natural conditions (in 2001 to 2004) or in trees managed in such a way to exclude rainfall. These conditions were then validated using pot-grown peach plants exposed to single infection events and independent orchard observations. Leaf curl incidence was related to rainfall, length of wet periods, and the temperature during wetness and during the incubation period, as well as to the developmental stage of flowers and fruit. Weather conditions before petal fall did not influence fruit infection. After petal fall, rainfall and the duration of the wet period triggered by rainfall played a key role in infection occurrence. The minimum rainfall required for infection was 12 mm, with at least 24 h of wetness interrupted by no more than 4 h. No infection occurred when temperature was >/=17 degrees C during the wet period or >19 degrees C during incubation. Disease symptoms appeared on fruit after approximately 3 weeks of incubation, which is equivalent to 240- to 290-degree-days (base 0 degrees C). The period for fruit infection was relatively short being from petal fall until air temperature remained greater than 16 degrees C. During this period, the incidence of fruit that developed symptoms was closely related to the number of favorable events and the total wetness duration during such events.

18.
J Ultrasound ; 10(1): 12-21, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23396402

RESUMEN

Portal vein thrombosis (PVT) is a rare cause of portal hypertension. Its diagnosis has been facilitated by improvements in imaging techniques, in particular Doppler sonography. The prevalence is about 1% in the general population, but much higher rates are observed in patients with hepatic cirrhosis (7%, range 0.6-17%), particularly those who also have hepatocellular carcinoma (HCC) (35%). The most common causes of PVT are myeloproliferative disorders, deficiencies of anticoagulant proteins, prothrombotic gene mutations, cirrhosis with portal hypertension, and HCC. Its development often requires the presence of two or more risk factors (local and/or systemic), e.g., a genetically determined thrombophilic state plus an infectious episode or abdominal surgery. It is clinically useful to distinguish between cirrhotic and noncirrhotic forms. Portal vein thrombosis is also traditionally classified as acute or chronic, but this distinction is often difficult. Color Doppler ultrasound is the first-line imaging study for diagnosis of PVT; magnetic resonance angiography and CT angiography are valid alternatives. The main complications are ischemic intestinal necrosis (in acute PVT) and esophageal varices (in chronic cases); the natural history of the latter differs depending on whether or not the thrombosis is associated with cirrhosis. The treatment of choice for PVT has never been adequately investigated. It is currently based on the use of anticoagulants associated, in some cases, with thrombolytics, but experience with the latter agents is too limited to draw any definite conclusions. In chronic thrombosis (even forms associated with cirrhosis), anticoagulant therapy is recommended and possibly, beta-blockers as well. Naturally, treatment of the underlying pathology is essential.

19.
Phytopathology ; 96(2): 155-63, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18943918

RESUMEN

ABSTRACT The effect of weather conditions on the infection of peach shoots by Taphrina deformans was investigated both under orchard conditions and in controlled-environment experiments. Leaf curl incidence and severity were related to rainfall, length of wet periods, and temperature during wetness and during the incubation period, as well as to the development stage of shoots. Surface wetness was more important than rainfall for infection to occur. Minimum rainfall for infection was 3 mm, with a wet period of at least 12.5 h; higher amounts of rainfall did not cause infection when the wet period they triggered was shorter. Wet periods initiated by dew or fog were too short for infection to occur. Infection occurred only when air temperature was <16 degrees C during the wet period and <19 degrees C during incubation. Logistic equations relating relative disease incidence and either duration of wetness or temperature were developed under controlled-environment conditions, with asymptotes at >/=48 h of wetness and

20.
Cell Mol Biol (Noisy-le-grand) ; 51(4): 363-70, 2005 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-16309586

RESUMEN

Heme oxygenase (HO-1) has been implicated as an anti-inflammatory gene. HO-1 overexpression, transiently and chronically, affects heme protein expression, attenuates TNF-mediated cell death, and decreases adhesion molecules. We assessed the effect of oxidant-mediated agents such as glucose and heme on 8-epi-isoprostane PGF2alpha (8-epi-PGF2alpha) and monocyte chemoattractant protein-1 (MCP-1). Glucose and heme increased both 8-epi-PGF2alpha and MCP-1. Overexpression of HO-1 decreased both 8-epi-PGF2alpha and MCP-1. To identify target genes involved in HO-1-mediated regulation of inflammation, a serial analysis of gene expression mRNA profile was performed in endothelial cells (EC) overexpressing the human HO-1 gene by transduction of a retrovirus carrying the HO-1 gene. Gene arrays (differential displays among 2400 genes) were used to identify known and novel differentially expressed genes. The levels of expression for several genes were confirmed by real time PCR in cells overexpressing the HO-1 gene. In HO-1 overexpressing cells, VEGF and the prostaglandin transporter were greatly increased while MCP-1 levels were decreased by 2.5-fold. The data from this study are relevant to understanding the mechanisms underlying the pathophysiological effects of HO-1 deficiency on endothelial cell injury and inflammation.


Asunto(s)
Ciclo Celular/genética , Quimiocina CCL2/metabolismo , Regulación hacia Abajo , Células Endoteliales/metabolismo , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/metabolismo , Células Cultivadas , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Regulación Enzimológica de la Expresión Génica , Glucosa/farmacología , Hemo/farmacología , Humanos , Inflamación/genética , Regulación hacia Arriba/genética
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