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1.
Circ J ; 85(12): 2149-2156, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34615815

RESUMO

BACKGROUND: To confirm the safety and efficacy of the IN.PACT Admiral drug-coated balloon (DCB) based on the indication approved by the Pharmaceuticals and Medical Devices Agency Japan in real-world patients with femoropopliteal artery disease.Methods and Results:IN.PACT PMS Japan was a prospective, multicenter, single-arm, post-market surveillance (PMS) study conducted in Japan that enrolled 304 participants (mean age 75.3±7.9 years). The primary endpoint was primary patency at 6 months following the index procedure, defined as freedom from clinically driven target lesion revascularization (CD-TLR) and freedom from restenosis as determined by duplex ultrasound (DUS) peak systolic velocity ratio (PSVR) ≤2.4 (assessed by the independent DUS core laboratory). Secondary endpoints included acute outcomes, primary patency at 12 months post-index procedure, freedom from CD-TLR, and major adverse events at 12 months. The mean lesion length was 97.81±58.97 mm. The primary endpoint, 6-month primary patency, was 91.3% (240/263). Kaplan-Meier estimates of primary patency and freedom from CD-TLR through 12 months were 91.5% and 94.1%, respectively. The CD-TLR rate was 5.8% (14/240) with low rates of thrombosis (0.8%) and target limb amputation (0.4%) at 12 months. CONCLUSIONS: The results of this real-world PMS study were consistent with outcomes from previous IN.PACT DCB studies, confirming the safety and efficacy of the IN.PACT Admiral DCB for broader use in patients seen in everyday practice.


Assuntos
Angioplastia com Balão , Fármacos Cardiovasculares , Doença Arterial Periférica , Dispositivos de Acesso Vascular , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Fármacos Cardiovasculares/efeitos adversos , Materiais Revestidos Biocompatíveis , Artéria Femoral/diagnóstico por imagem , Humanos , Japão , Paclitaxel/efeitos adversos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Artéria Poplítea/diagnóstico por imagem , Estudos Prospectivos , Resultado do Tratamento , Grau de Desobstrução Vascular
2.
Pharm Res ; 37(12): 250, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33237382

RESUMO

PURPOSE: To provide whole-body physiologically based pharmacokinetic (PBPK) models of the potent clinical organic anion transporter (OAT) inhibitor probenecid and the clinical OAT victim drug furosemide for their application in transporter-based drug-drug interaction (DDI) modeling. METHODS: PBPK models of probenecid and furosemide were developed in PK-Sim®. Drug-dependent parameters and plasma concentration-time profiles following intravenous and oral probenecid and furosemide administration were gathered from literature and used for model development. For model evaluation, plasma concentration-time profiles, areas under the plasma concentration-time curve (AUC) and peak plasma concentrations (Cmax) were predicted and compared to observed data. In addition, the models were applied to predict the outcome of clinical DDI studies. RESULTS: The developed models accurately describe the reported plasma concentrations of 27 clinical probenecid studies and of 42 studies using furosemide. Furthermore, application of these models to predict the probenecid-furosemide and probenecid-rifampicin DDIs demonstrates their good performance, with 6/7 of the predicted DDI AUC ratios and 4/5 of the predicted DDI Cmax ratios within 1.25-fold of the observed values, and all predicted DDI AUC and Cmax ratios within 2.0-fold. CONCLUSIONS: Whole-body PBPK models of probenecid and furosemide were built and evaluated, providing useful tools to support the investigation of transporter mediated DDIs.


Assuntos
Furosemida/farmacocinética , Modelos Biológicos , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Probenecid/farmacocinética , Administração Intravenosa , Administração Oral , Adulto , Biotransformação , Simulação por Computador , Vias de Eliminação de Fármacos , Interações Medicamentosas , Feminino , Furosemida/administração & dosagem , Furosemida/sangue , Humanos , Masculino , Transportadores de Ânions Orgânicos/metabolismo , Probenecid/administração & dosagem , Probenecid/sangue , Rifampina/farmacocinética
3.
Skin Res Technol ; 25(5): 735-742, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31074525

RESUMO

BACKGROUND: The human epidermis presents a complex organization due to its dynamic and plein-stratified epithelium. Still nowadays, one of the best method to study this layer of the skin remains the histology sections. This approach remains tedious and gives only 2D information. MATERIALS AND METHODS: Rhodamine B is a dye known to have a high affinity for the epidermal layer and to possess fluorescent properties. Associated with a clarification method such as 3DiSCO, this dye maintains a high fluorescence emission. The skin which became transparent can then be investigated with a Laser Scanning Confocal Microscope. RESULTS: We showed that this technique can collect longitudinal or transversal optical sections of the epidermis as whole. Serial sections allowed to move easily into the epidermis. A 3D imaging can also be generated to study the microrelief of the stratum corneum or the complex organization of the dermal-epidermal junction. CONCLUSION: In this work, we describe a simple and fast staining and clearing method for skin samples. In association with a fluorescence microscope such as the confocal, we show a new way to characterize the whole epidermis. This work appears as a valuable and complementary method to understand several topics around skin investigation.


Assuntos
Células Epidérmicas/citologia , Epiderme/diagnóstico por imagem , Epiderme/anatomia & histologia , Corantes Fluorescentes , Humanos , Imageamento Tridimensional , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Rodaminas
4.
Rev Esp Enferm Dig ; 111(10): 775-788, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31538484

RESUMO

BACKGROUND AND AIMS: heterozygous ABCB4, ABCB11 and ATP8B1 sequence variants were previously reported to be associated with low phospholipid-associated cholelithiasis, intrahepatic cholestasis of pregnancy, benign recurrent intrahepatic cholestasis and biliary lithiasis. The present study aimed to identify the presence of sequence variations in genes responsible for Mendelian liver disorders in patients with cholestatic liver disease. METHODS: targeted massive parallel sequencing of a panel of genes involved in bile acid homeostasis was performed in 105 young and adult patients with cholestatic liver disease in our laboratory for molecular diagnosis. The effects of novel variants were evaluated using bioinformatics prediction tools and the Protter and Phyre2 software programs were used to create 2D, 3D topology protein modeling. Genotype-phenotype correlation was established according to molecular analysis and clinical records. RESULTS: twenty novel heterozygous ABCB4 sequence variations, one heterozygous ABCB4 large intragenic deletion and only one novel missense variant in ABCB11 and ATP8B1 were identified. Interestingly, heterozygous and homozygous SLC4A2 missense variants were detected in patients with low phospholipid-associated cholelithiasis. Two patients harbored heterozygous GPBAR1 variants. Common variants such as homozygous ABCB11 p.Val444Ala and heterozygous ABCG8 p.Asp19His were also identified in 12 cases. CONCLUSIONS: forty-eight variants were identified in five genes including ABCB4, ABCB11, ATP8B1, SLC4A2 and GPBAR1, twenty-five of which were novel. This study expands the phenotypic and mutational spectrum in genes involved in bile acid homeostasis and highlights the genetic and phenotypic heterogeneity in patients with inherited liver disorders.


Assuntos
Colestase Intra-Hepática/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Adenosina Trifosfatases/genética , Adolescente , Adulto , Ácidos e Sais Biliares/genética , Ácidos e Sais Biliares/metabolismo , Criança , Antiportadores de Cloreto-Bicarbonato/genética , Feminino , Predisposição Genética para Doença , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Homeostase , Homozigoto , Humanos , Masculino , Mutação de Sentido Incorreto , Linhagem , Receptores Acoplados a Proteínas G/genética , Adulto Jovem
5.
J Endovasc Ther ; 25(6): 673-682, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30280648

RESUMO

PURPOSE: To report a post hoc analysis comparing outcomes between subjects who would have been included in the IN.PACT SFA randomized controlled trial vs those who would have been excluded. METHODS: The 1406 subjects enrolled in the IN.PACT Global Study ( ClinicalTrials.gov identifier NCT01609296) were retrospectively assigned to a standard-use group (n=281) based on the inclusion and exclusion criteria from the randomized IN.PACT SFA trial; the remaining 1125 patients were assigned to the broader-use group. Freedom from clinically-driven target lesion revascularization (CD-TLR) was evaluated at 12 months. The composite primary safety endpoint was freedom from 30-day device- and procedure-related death plus freedom from 12-month target limb major amputation and clinically-driven target vessel revascularization (CD-TVR). Functional outcomes were evaluated with dedicated questionnaires. RESULTS: Compared with the standard-use cohort, the broader-use lesions were longer, more calcified, and had more popliteal involvement, bilateral disease, and in-stent restenosis (p<0.001 for all). Freedom from 12-month CD-TLR by Kaplan-Meier analysis was 96.6% for the standard-use group and 91.6% for the broader-use group (p=0.005). The safety endpoint was 96.2% in the standard-use group and 91.0% in the broader-use group (p=0.003). The 12-month CD-TLR (3.4% standard-use vs 8.5% broader-use, p=0.004) and CD-TVR (4.2% standard-use vs 9.1% broader-use, p=0.008) were increased in the broader-use group. Twelve-month all-cause mortality was not increased (3.8% standard-use vs 3.4% broader-use, p=0.852). CONCLUSION: Post hoc analysis of the IN.PACT Global Study of real-world patients demonstrated consistent outcomes with significant clinical improvement to 12 months in subjects with complex lesions typically excluded from a randomized controlled trial.


Assuntos
Angioplastia com Balão/instrumentação , Materiais Revestidos Biocompatíveis , Artéria Femoral , Seleção de Pacientes , Doença Arterial Periférica/terapia , Artéria Poplítea , Dispositivos de Acesso Vascular , Idoso , Angioplastia com Balão/efeitos adversos , Desenho de Equipamento , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/fisiopatologia , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Fatores de Tempo , Grau de Desobstrução Vascular
6.
J Cachexia Sarcopenia Muscle ; 14(6): 2882-2897, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37964752

RESUMO

BACKGROUND: Decreased ryanodine receptor type 1 (RyR1) protein levels are a well-described feature of recessive RYR1-related myopathies. The aim of the present study was twofold: (1) to determine whether RyR1 content is also decreased in other myopathies and (2) to investigate the mechanisms by which decreased RyR1 protein triggers muscular disorders. METHODS: We used publicly available datasets, muscles from human inflammatory and mitochondrial myopathies, an inducible muscle-specific RYR1 recessive mouse model and RyR1 knockdown in C2C12 muscle cells to measure RyR1 content and endoplasmic reticulum (ER) stress markers. Proteomics, lipidomics, molecular biology and transmission electron microscopy approaches were used to decipher the alterations associated with the reduction of RyR1 protein levels. RESULTS: RYR1 transcripts were reduced in muscle samples of patients suffering from necrotizing myopathy (P = 0.026), inclusion body myopathy (P = 0.003), polymyositis (P < 0.001) and juvenile dermatomyositis (P < 0.001) and in muscle samples of myotonic dystrophy type 2 (P < 0.001), presymptomatic (P < 0.001) and symptomatic (P < 0.001) Duchenne muscular dystrophy, Becker muscular dystrophy (P = 0.004) and limb-girdle muscular dystrophy type 2A (P = 0.004). RyR1 protein content was also significantly decreased in inflammatory myopathy (-75%, P < 0.001) and mitochondrial myopathy (-71%, P < 0.001) muscles. Proteomics data showed that depletion of RyR1 protein in C2C12 myoblasts leads to myotubes recapitulating the common molecular alterations observed in myopathies. Mechanistically, RyR1 protein depletion reduces ER-mitochondria contact length (-26%, P < 0.001), Ca2+ transfer to mitochondria (-48%, P = 0.002) and the mitophagy gene Parkinson protein 2 transcripts (P = 0.037) and induces mitochondrial accumulation (+99%, P = 0.005) and dysfunction (P < 0.001). This was associated to the accumulation of deleterious sphingolipid species. Our data showed increased levels of the ER stress marker chaperone-binding protein/glucose regulated protein 78, GRP78-Bip, in RyR1 knockdown myotubes (+45%, P = 0.046), in mouse RyR1 recessive muscles (+58%, P = 0.001) and in human inflammatory (+96%, P = 0.006) and mitochondrial (+64%, P = 0.049) myopathy muscles. This was accompanied by increased protein levels of the pro-apoptotic protein CCAAT-enhancer-binding protein homologous protein, CHOP-DDIT3, in RyR1 knockdown myotubes (+27%, P < 0.001), mouse RyR1 recessive muscles (+63%, P = 0.009), human inflammatory (+50%, P = 0.038) and mitochondrial (+51%, P = 0.035) myopathy muscles. In publicly available datasets, the decrease in RYR1 content in myopathies was also associated to increased ER stress markers and RYR1 transcript levels are inversely correlated with ER stress markers in the control population. CONCLUSIONS: Decreased RyR1 is commonly observed in myopathies and associated to ER stress in vitro, in mouse muscle and in human myopathy muscles, suggesting a potent role of RyR1 depletion-induced ER stress in the pathogenesis of myopathies.


Assuntos
Doenças Musculares , Canal de Liberação de Cálcio do Receptor de Rianodina , Animais , Humanos , Camundongos , Estresse do Retículo Endoplasmático , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/patologia , Doenças Musculares/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
7.
FEBS Lett ; 596(11): 1434-1444, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35294049

RESUMO

Adipose tissue regulates whole-body energy homeostasis. Both lipodystrophy and obesity, the extreme and opposite aspects of adipose tissue dysfunction, result in metabolic disorders: insulin resistance and hepatic steatosis. Cyclin-dependent kinases (CDKs) have been reported to be involved in adipose tissue development and functions. Using adipose tissue-specific knockout mice, here we demonstrate that the deletion of CDK7 in adipose tissue results in progressive lipodystrophy, insulin resistance, impaired adipokine secretion and downregulation of fat-specific genes, which are aggravated on high-fat diet and during ageing. Our studies suggest that CDK7 is a key regulatory component of adipose tissue maintenance and systemic energy homeostasis.


Assuntos
Resistência à Insulina , Lipodistrofia , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético/genética , Resistência à Insulina/genética , Lipodistrofia/metabolismo , Camundongos , Camundongos Knockout
8.
Pharmaceutics ; 12(6)2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32560124

RESUMO

The calcium channel blocker and antiarrhythmic agent verapamil is recommended by the FDA for drug-drug interaction (DDI) studies as a moderate clinical CYP3A4 index inhibitor and as a clinical Pgp inhibitor. The purpose of the presented work was to develop a mechanistic whole-body physiologically based pharmacokinetic (PBPK) model to investigate and predict DDIs with verapamil. The model was established in PK-Sim®, using 45 clinical studies (dosing range 0.1-250 mg), including literature as well as unpublished Boehringer Ingelheim data. The verapamil R- and S-enantiomers and their main metabolites R- and S-norverapamil are represented in the model. The processes implemented to describe the pharmacokinetics of verapamil and norverapamil include enantioselective plasma protein binding, enantioselective metabolism by CYP3A4, non-stereospecific Pgp transport, and passive glomerular filtration. To describe the auto-inhibitory and DDI potential, mechanism-based inactivation of CYP3A4 and non-competitive inhibition of Pgp by the verapamil and norverapamil enantiomers were incorporated based on in vitro literature. The resulting DDI performance was demonstrated by prediction of DDIs with midazolam, digoxin, rifampicin, and cimetidine, with 21/22 predicted DDI AUC ratios or Ctrough ratios within 1.5-fold of the observed values. The thoroughly built and qualified model will be freely available in the Open Systems Pharmacology model repository to support model-informed drug discovery and development.

9.
PLoS Comput Biol ; 2(12): e176, 2006 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-17194217

RESUMO

Integration of neurotransmitter and neuromodulator signals in the striatum plays a central role in the functions and dysfunctions of the basal ganglia. DARPP-32 is a key actor of this integration in the GABAergic medium-size spiny neurons, in particular in response to dopamine and glutamate. When phosphorylated by cAMP-dependent protein kinase (PKA), DARPP-32 inhibits protein phosphatase-1 (PP1), whereas when phosphorylated by cyclin-dependent kinase 5 (CDK5) it inhibits PKA. DARPP-32 is also regulated by casein kinases and by several protein phosphatases. These complex and intricate regulations make simple predictions of DARPP-32 dynamic behaviour virtually impossible. We used detailed quantitative modelling of the regulation of DARPP-32 phosphorylation to improve our understanding of its function. The models included all the combinations of the three best-characterized phosphorylation sites of DARPP-32, their regulation by kinases and phosphatases, and the regulation of those enzymes by cAMP and Ca(2+) signals. Dynamic simulations allowed us to observe the temporal relationships between cAMP and Ca(2+) signals. We confirmed that the proposed regulation of protein phosphatase-2A (PP2A) by calcium can account for the observed decrease of Threonine 75 phosphorylation upon glutamate receptor activation. DARPP-32 is not simply a switch between PP1-inhibiting and PKA-inhibiting states. Sensitivity analysis showed that CDK5 activity is a major regulator of the response, as previously suggested. Conversely, the strength of the regulation of PP2A by PKA or by calcium had little effect on the PP1-inhibiting function of DARPP-32 in these conditions. The simulations showed that DARPP-32 is not only a robust signal integrator, but that its response also depends on the delay between cAMP and calcium signals affecting the response to the latter. This integration did not depend on the concentration of DARPP-32, while the absolute effect on PP1 varied linearly. In silico mutants showed that Ser137 phosphorylation affects the influence of the delay between dopamine and glutamate, and that constitutive phosphorylation in Ser137 transforms DARPP-32 in a quasi-irreversible switch. This work is a first attempt to better understand the complex interactions between cAMP and Ca(2+) regulation of DARPP-32. Progressive inclusion of additional components should lead to a realistic model of signalling networks underlying the function of striatal neurons.


Assuntos
Gânglios da Base/metabolismo , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Dopamina/metabolismo , Ácido Glutâmico/metabolismo , Modelos Biológicos , Modelos Neurológicos , Transmissão Sináptica/fisiologia , Simulação por Computador , Fosforilação
10.
FEBS J ; 272(10): 2578-90, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15885106

RESUMO

Calpain 1, a ubiquitous calcium-dependent intracellular protease, was recently found in a tight association with myofibrils in skeletal muscle tissue [Delgado EF, Geesink GH, Marchello JA, Goll DE & Koohmaraie M (2001) J Anim Sci79, 2097-2107). Our immunofluorescence and immunoelectron microscopy investigations restrain the protease location at the periphery of the Z-band and at the midpoint of the I-band. Furthermore, calpain 1 is found to localize in myofibril fractures, described as proteolysis sites, in postmortem bovine skeletal red muscles, near the calcium deposits located at the N1 and N2 level. This in situ localization of calpain 1 is substantiated by binding assays with two titin regions covering the I-band region: a native fragment of 150 kDa (identified by mass spectrometry) that includes the N-terminal Z8-I5 region and the N1-line region of titin, and an 800 kDa fragment external to the N1 line that bears the PEVK/N2 region. These two titin fragments are shown to tightly bind calpain 1 in the presence of CaCl(2) and E64, a calpain inhibitor. In the absence of E64, they are cleaved by calpain 1. We conclude that titin affords binding sites to calpain 1, which concentrates the protease in the regions restrained by the Z-band edge and the N1-line as well as at the N2-line level, two sarcomeric regions where early postmortem proteolysis is detected.


Assuntos
Calpaína/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Miofibrilas/metabolismo , Miofibrilas/ultraestrutura , Proteínas Quinases/metabolismo , Animais , Cálcio/metabolismo , Calpaína/genética , Bovinos , Conectina , Humanos , Imunoglobulina G/metabolismo , Imuno-Histoquímica , Camundongos , Dados de Sequência Molecular , Proteínas Musculares/química , Proteínas Musculares/genética , Músculo Esquelético/citologia , Ligação Proteica , Proteínas Quinases/química , Proteínas Quinases/genética , Coelhos , Ratos , Suínos
11.
Shock ; 24(2): 109-13, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16044079

RESUMO

Whether methicillin-resistant Staphylococcus aureus (MRSA) constitutes per se an independent risk factor for morbidity and mortality after surgery as compared with methicillin-sensitive Staphylococcus aureus (MSSA) remains a subject of debate. The aim of this study was to assess whether innate defenses against MRSA and MSSA strains are similarly impaired after cardiac surgery. Both intracellular (isolated neutrophil functions) and extracellular (plasma) defenses of 12 patients undergoing scheduled cardiac surgery were evaluated preoperatively (day 0) and postoperatively (day 3) against two MSSA strains with a low level of catalase secretion and two MRSA strains with a high level of catalase secretion, inasmuch as SA killing by neutrophils relies on oxygen-dependent mechanisms. After surgery, an increase in plasma concentration of IL-10, an anti-inflammatory cytokine able to inhibit reactive oxygen species secretion and bactericidal activity of neutrophils, was evidenced. Despite the fact that univariate analysis suggested a specific impairment of neutrophil functions against MRSA strains, two-way repeated-measures ANOVA failed to demonstrate that the effect of S. aureus phenotype was significant. On the other hand, an increase in type-II secretory phospholipase A2 activity, a circulating enzyme involved in SA lysis, was evidenced and was associated with an enhancement of extracellular defenses (bactericidal activity of plasma) against MRSA. Overall, cardiac surgery and S. aureus phenotype had a significant effect on plasma bactericidal activity. Cardiac surgery was characterized by enhanced antibacterial defenses of plasma, whereas neutrophil killing properties were reduced. The overall effect of S. aureus phenotype on neutrophil functions did not seem significant.


Assuntos
Anti-Infecciosos/farmacologia , Atividade Bactericida do Sangue/efeitos dos fármacos , Ponte Cardiopulmonar/métodos , Resistência a Meticilina , Meticilina/farmacologia , Neutrófilos/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/metabolismo , Idoso , Análise de Variância , Catalase/metabolismo , Feminino , Citometria de Fluxo , Humanos , Peróxido de Hidrogênio/farmacologia , Interleucina-10/sangue , Interleucina-10/metabolismo , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Oxigênio/metabolismo , Fagocitose , Fenótipo , Espécies Reativas de Oxigênio , Fatores de Tempo
13.
J Neuroimmunol ; 142(1-2): 93-100, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14512168

RESUMO

Anti-Hu syndrome is a paraneoplastic neurologic disease seemingly associated with an efficient antitumoral immune response against HuD protein expressed by both small cell lung cancer (SCLC) and neurons. Since anti-Hu antibodies are not pathogenic, and oligoclonal CD8(+) T cells infiltrate neoplastic and nervous tissues, we examined MHC class I-restricted immunogenicity of human HuD. Among 14 HuD-derived peptides potentially immunogenic in HLA-A*0201 restriction, 10 had actual in vitro binding capacity to the HLA molecule, 8 elicited specific cytotoxic T lymphocytes (CTLs) in a humanized murine model after peptidic vaccination, 2 also elicited specific CTLs in healthy humans, and 1 was naturally processed and presented to the immune system.


Assuntos
Antígenos de Neoplasias/imunologia , Citotoxicidade Imunológica/imunologia , Proteínas do Tecido Nervoso/imunologia , Síndromes Paraneoplásicas do Sistema Nervoso/imunologia , Fragmentos de Peptídeos/imunologia , Proteínas de Ligação a RNA/imunologia , Animais , Apresentação de Antígeno , Antígenos de Neoplasias/administração & dosagem , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Proteínas ELAV , Proteína Semelhante a ELAV 4 , Antígenos HLA-A/imunologia , Antígenos HLA-A/metabolismo , Antígeno HLA-A2 , Humanos , Injeções Intramusculares , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteínas do Tecido Nervoso/administração & dosagem , Proteínas do Tecido Nervoso/metabolismo , Síndromes Paraneoplásicas do Sistema Nervoso/genética , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/metabolismo , Ligação Proteica/imunologia , Proteínas de Ligação a RNA/administração & dosagem , Proteínas de Ligação a RNA/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia
14.
Eur J Biochem ; 270(23): 4662-70, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14622253

RESUMO

Calpain 1 behaviour toward cytoskeletal targets was investigated using two alpha-actinin isoforms from smooth and skeletal muscles. These two isoforms which are, respectively, sensitive and resistant to calpain cleavage, interact with the protease when using in vitro binding assays. The stability of the complexes in EGTA [Kd(-Ca2+) = 0.5 +/- 0.1 microM] was improved in the presence of 1 mm calcium ions [Kd(+Ca2+) = 0.05 +/- 0.01 microM]. Location of the binding structures shows that the C-terminal domain of alpha-actinin and each calpain subunit, 28 and 80 kDa, participates in the interaction. In particular, the autolysed calpain form (76/18) affords a similar binding compared to the 80/28 intact enzyme, with an identified binding site in the catalytic subunit, located in the C-terminal region of the chain (domain III-IV). The in vivo colocalization of calpain 1 and alpha-actinin was shown to be likely in the presence of calcium, when permeabilized muscle fibres were supplemented by exogenous calpain 1 and the presence of calpain 1 in Z-line cores was shown by gold-labelled antibodies. The demonstration of such a colocalization was brought by coimmunoprecipitation experiments of calpain 1 and alpha-actinin from C2.7 myogenic cells. We propose that calpain 1 interacts in a resting state with cytoskeletal targets, and that this binding is strengthened in pathological conditions, such as ischaemia and dystrophies, associated with high calcium concentrations.


Assuntos
Actinina/metabolismo , Calpaína/metabolismo , Citoesqueleto/metabolismo , Actinina/química , Animais , Sítios de Ligação , Cálcio/metabolismo , Cálcio/farmacologia , Calpaína/química , Bovinos , Linhagem Celular , Humanos , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Subunidades Proteicas/metabolismo
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