RESUMO
Avalglucosidase alfa (AVAL) was approved in the United States (2021) for patients with late-onset Pompe disease (LOPD), aged ≥ 1 year. In the present study, pharmacokinetic (PK) simulations were conducted to propose alternative dosing regimens for pediatric LOPD patients based on a bodyweight cut-off. Population PK (PopPK) analysis was performed using nonlinear mixed effect modeling approach on pooled data from three clinical trials with LOPD patients, and a phase 2 study (NCT03019406) with infantile-onset Pompe disease (IOPD: 1-12 years) patients. A total of 2257 concentration-time points from 91 patients (LOPD, n = 75; IOPD, n = 16) were included in the analysis. The model was bodyweight dependent allometric scaling with time varying bodyweight included on clearance and distribution volume. Simulations were performed for two dosing regimens (20 mg/kg or 40 mg/kg) with different bodyweight cut-off (25, 30, 35 and 40 kg) by generating virtual pediatric (1-17 years) and adult patients. Corresponding simulated individual exposures (maximal concentration, Cmax and area under the curve in the 2-week dosing interval, AUC2W), and distributions were calculated. It was found that dosing of 40 mg/kg and 20 mg/kg in pediatric patients < 30 kg and ≥ 30 kg, respectively, achieved similar AVAL exposure (based on AUC2W) to adult patients receiving 20 mg/kg. PK simulations conducted on the basis of this model provided supporting data for the currently approved US labelling for dosing adapted bodyweight in LOPD patients ≥ 1 year by USFDA.
Assuntos
Doença de Depósito de Glicogênio Tipo II , Adulto , Humanos , Criança , Estados Unidos , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/induzido quimicamente , Doença de Depósito de Glicogênio Tipo II/epidemiologia , alfa-Glucosidases/efeitos adversos , alfa-Glucosidases/metabolismo , Peso Corporal , CinéticaRESUMO
BACKGROUND: Pompe disease (PD) is a disorder of glycogen metabolism conditioning a progressive and life conditioning myopathy. Enzyme replacement therapy (ERT) is currently the best treatment option for PD, but is not resolutive. While other potential therapeutic approaches have been reported before, these have never been tried as co- treatments. L-alanine oral supplementation (LAOS) has been proven to reduce muscle breakdown: we hereby report the first case of supplementation on a PD patient on ERT. CASE PRESENTATION: F. is a 9 y.o. infantile onset Pompe Disease (IOPD) girl ERT-treated since age 1 developing a progressive myopathy. We started her on LAOS and performed assessments at baseline, 6 and 9 months. At baseline, F.'s weight, height and BMI were within normal ranges, while body composition showed low fat mass -FM and high resting energy expenditure-REE levels. After LAOS, a progressive FM increase and REE reduction could be observed both at 6 and 9 months. CONCLUSIONS: ERT is not curative for PD patients thus additional treatments could be considered to improve outcomes. Our patient showed physical signs of inability to accumulate energy when exclusively on ERT, while FM increase and REE reduction occurred when supplemented with LAOS, likely reflecting anabolic pathways' implementation. This is the first case reporting potential LAOS benefits in PD-on ERT patients. Longitudinal case control studies are yet needed to evaluate possible efficacy of combined LAOS And ERT treatment in PD patients.
Assuntos
Doença de Depósito de Glicogênio Tipo II , Alanina/uso terapêutico , Suplementos Nutricionais , Terapia de Reposição de Enzimas , Feminino , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Humanos , Lactente , alfa-Glucosidases/metabolismo , alfa-Glucosidases/uso terapêuticoRESUMO
BACKGROUND: Metabolic myopathies are a heterogenous group of muscle diseases typically characterized by exercise intolerance, myalgia and progressive muscle weakness. Effective treatments for some of these diseases are available, but while our understanding of the pathogenesis of metabolic myopathies related to glycogen storage, lipid metabolism and ß-oxidation is well established, evidence linking treatments with the precise causative genetic defect is lacking. OBJECTIVE: The objective of this study was to collate all published evidence on pharmacological therapies for the aforementioned metabolic myopathies and link this to the genetic mutation in a format amenable to databasing for further computational use in line with the principles of the "treatabolome" project. METHODS: A systematic literature review was conducted to retrieve all levels of evidence examining the therapeutic efficacy of pharmacological treatments on metabolic myopathies related to glycogen storage and lipid metabolism. A key inclusion criterion was the availability of the genetic variant of the treated patients in order to link treatment outcome with the genetic defect. RESULTS: Of the 1,085 articles initially identified, 268 full-text articles were assessed for eligibility, of which 87 were carried over into the final data extraction. The most studied metabolic myopathies were Pompe disease (45 articles), multiple acyl-CoA dehydrogenase deficiency related to mutations in the ETFDH gene (15 articles) and systemic primary carnitine deficiency (8 articles). The most studied therapeutic management strategies for these diseases were enzyme replacement therapy, riboflavin, and carnitine supplementation, respectively. CONCLUSIONS: This systematic review provides evidence for treatments of metabolic myopathies linked with the genetic defect in a computationally accessible format suitable for databasing in the treatabolome system, which will enable clinicians to acquire evidence on appropriate therapeutic options for their patient at the time of diagnosis.
Assuntos
Glicogênio/metabolismo , Metabolismo dos Lipídeos , Erros Inatos do Metabolismo/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Humanos , Deficiência Múltipla de Acil Coenzima A Desidrogenase/tratamento farmacológico , Debilidade Muscular , MutaçãoRESUMO
Pompe disease (PD) is an autosomal recessive muscular disorder caused by deficiency of the glycogen hydrolytic enzyme acid α-glucosidase (GAA). The enzyme replacement therapy, currently the only available therapy for PD patients, is efficacious in improving cardiomyopathy in the infantile form, but not equally effective in the late onset cases with involvement of skeletal muscle. Correction of the skeletal muscle phenotype has indeed been challenging, probably due to concomitant dysfunctional autophagy. The increasing attention to the pathogenic mechanisms of PD and the search of new therapeutic strategies prompted us to generate and characterize a novel transient PD model, using zebrafish. Our model presented increased glycogen content, markedly altered motor behavior and increased lysosome content, in addition to altered expression of the autophagy-related transcripts and proteins Beclin1, p62 and Lc3b. Furthermore, the model was used to assess the beneficial effects of 3-bromopyruvic acid (3-BrPA). Treatment with 3-BrPA induced amelioration of the model phenotypes regarding glycogen storage, motility behavior and autophagy-related transcripts and proteins. Our zebrafish PD model recapitulates most of the defects observed in human patients, proving to be a powerful translational model. Moreover, 3-BrPA unveiled to be a promising compound for treatment of conditions with glycogen accumulation.
Assuntos
Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Glicogênio/metabolismo , Hexoquinase/antagonistas & inibidores , Piruvatos/farmacologia , Animais , Animais Geneticamente Modificados , Autofagia/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Técnicas de Silenciamento de Genes , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/patologia , Glicólise/efeitos dos fármacos , Hexoquinase/metabolismo , Humanos , Lisossomos , Microscopia Eletrônica , Morfolinos/administração & dosagem , Morfolinos/genética , Atividade Motora/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Piruvatos/uso terapêutico , Peixe-Zebra , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismoRESUMO
Pompe disease (OMIM # 232300) is a glycogen storage disease caused by autosomal recessive mutations of the gene encoding alpha-1,4-glucosidase (GAA; EC 3.2.1.20). Despite the relatively effective employment of enzyme replacement therapy, some critical medical issues still exist in patients with this disease, including the persistence of abnormalities in the central nervous system (CNS), probably because of the inability of the recombinant GAA to pass through the blood-brain barrier. To address this issue, identification of more therapeutic agents that target the CNS of patients with Pompe disease may be required. In this study, we derived neuronal cells from Pompe disease-induced pluripotent stem cells (Pom-iPSCs) and proved that they are able to recapitulate the hallmark cellular and biochemical phenotypes of Pompe disease. Using the Pom-iPSC-derived neurons as an in vitro drug-testing model, we then identified three compounds, ebselen, wortmannin and PX-866, with therapeutic potential to alleviate Pompe disease-associated pathological phenotypes in the neurons derived from Pom-iPSCs. We confirmed that all three compounds were able to enhance the GAA activity in the Pom-iPSC-derived neurons. Moreover, they were able to enhance the GAA activity in several important internal organs of GAA-deficient mice when co-injected with recombinant human GAA, and we found that intraperitoneal injection of ebselen was able to promote the GAA activity of the GAA-heterozygous mouse brain. Our results prove the usefulness of Pom-iPSC-derived neuronal populations for identifying new compounds with therapeutic potential.
Assuntos
Azóis/administração & dosagem , Doença de Depósito de Glicogênio Tipo II/patologia , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Neurais/citologia , Compostos Organosselênicos/administração & dosagem , alfa-Glucosidases/metabolismo , Animais , Azóis/farmacologia , Barreira Hematoencefálica , Encéfalo/metabolismo , Técnicas de Cultura de Células , Células Cultivadas , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/metabolismo , Gonanos/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Injeções Intraperitoneais , Isoindóis , Masculino , Camundongos , Células-Tronco Neurais/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Wortmanina/farmacologia , alfa-Glucosidases/genéticaRESUMO
Pompe disease is a rare inherited disorder of lysosomal glycogen metabolism due to acid α-glucosidase (GAA) deficiency. Enzyme replacement therapy (ERT) using alglucosidase alfa, a recombinant human GAA (rhGAA), is the only approved treatment for Pompe disease. Although alglucosidase alfa has provided clinical benefits, its poor targeting to key disease-relevant skeletal muscles results in suboptimal efficacy. We are developing an rhGAA, ATB200 (Amicus proprietary rhGAA), with high levels of mannose-6-phosphate that are required for efficient cellular uptake and lysosomal trafficking. When administered in combination with the pharmacological chaperone AT2221 (miglustat), which stabilizes the enzyme and improves its pharmacokinetic properties, ATB200/AT2221 was substantially more potent than alglucosidase alfa in a mouse model of Pompe disease. The new investigational therapy is more effective at reversing the primary abnormality - intralysosomal glycogen accumulation - in multiple muscles. Furthermore, unlike the current standard of care, ATB200/AT2221 dramatically reduces autophagic buildup, a major secondary defect in the diseased muscles. The reversal of lysosomal and autophagic pathologies leads to improved muscle function. These data demonstrate the superiority of ATB200/AT2221 over the currently approved ERT in the murine model.
Assuntos
Terapia de Reposição de Enzimas/métodos , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , alfa-Glucosidases/farmacologia , alfa-Glucosidases/uso terapêutico , 1-Desoxinojirimicina/análogos & derivados , Animais , Modelos Animais de Doenças , Feminino , Glicogênio/metabolismo , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/patologia , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Masculino , Manosefosfatos/metabolismo , Camundongos , Camundongos Knockout , Músculo Esquelético/metabolismo , Ratos , Ratos Sprague-Dawley , alfa-Glucosidases/sangue , alfa-Glucosidases/genéticaRESUMO
The highly stereocontrolled de novo synthesis of l-NBDNJ (the unnatural enantiomer of the iminosugar drug Miglustat) and a preliminary evaluation of its chaperoning potential are herein reported. l-NBDNJ is able to enhance lysosomal α-glucosidase levels in Pompe disease fibroblasts, either when administered singularly or when coincubated with the recombinant human α-glucosidase. In addition, differently from its d-enantiomer, l-NBDNJ does not act as a glycosidase inhibitor.
Assuntos
1-Desoxinojirimicina/análogos & derivados , Ativação Enzimática/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , alfa-Glucosidases/metabolismo , 1-Desoxinojirimicina/síntese química , 1-Desoxinojirimicina/química , 1-Desoxinojirimicina/farmacologia , Regulação Alostérica/efeitos dos fármacos , Linhagem Celular , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Doença de Depósito de Glicogênio Tipo II/enzimologia , Doença de Depósito de Glicogênio Tipo II/metabolismo , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/enzimologia , Lisossomos/metabolismo , Modelos Moleculares , EstereoisomerismoRESUMO
Classic infantile-onset Pompe disease (IOPD), characterized by predominantly cardiac involvement, used to be considered uniformly lethal within months. The availability of enzyme replacement therapy (ERT) has transformed the course of the disease. Decrease in ventricular hypertrophy and improvement in ventricular function have been suggested as proof for efficacy. We report the cardiac response to ERT of a child with IOPD and severe hypertrophic cardiomyopathy. The myocardial hypertrophy resolved. Change in ejection fraction, however, was slow. We discuss the potential benefit of other parameters beyond ejection to assess cardiac function in IOPD, including speckle tracking-based strain.
Assuntos
Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/tratamento farmacológico , Terapia de Reposição de Enzimas/métodos , Doença de Depósito de Glicogênio Tipo II/complicações , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Acarbose/uso terapêutico , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Ecocardiografia , Ecocardiografia Doppler , Feminino , Glucosidases/uso terapêutico , Doença de Depósito de Glicogênio Tipo II/diagnóstico por imagem , Inibidores de Glicosídeo Hidrolases/uso terapêutico , Humanos , Lactente , Resultado do TratamentoRESUMO
Duvoglustat HCl (AT2220, 1-deoxynojirimycin) is an investigational pharmacological chaperone for the treatment of acid α-glucosidase (GAA) deficiency, which leads to the lysosomal storage disorder Pompe disease, which is characterized by progressive accumulation of lysosomal glycogen primarily in heart and skeletal muscles. The current standard of care is enzyme replacement therapy with recombinant human GAA (alglucosidase alfa [AA], Genzyme). Based on preclinical data, oral co-administration of duvoglustat HCl with AA increases exposure of active levels in plasma and skeletal muscles, leading to greater substrate reduction in muscle. This phase 2a study consisted of an open-label, fixed-treatment sequence that evaluated the effect of single oral doses of 50 mg, 100 mg, 250 mg, or 600 mg duvoglustat HCl on the pharmacokinetics and tissue levels of intravenously infused AA (20 mg/kg) in Pompe patients. AA alone resulted in increases in total GAA activity and protein in plasma compared to baseline. Following co-administration with duvoglustat HCl, total GAA activity and protein in plasma were further increased 1.2- to 2.8-fold compared to AA alone in all 25 Pompe patients; importantly, muscle GAA activity was increased for all co-administration treatments from day 3 biopsy specimens. No duvoglustat-related adverse events or drug-related tolerability issues were identified.
Assuntos
1-Desoxinojirimicina/uso terapêutico , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Lisossomos/enzimologia , Músculo Esquelético/efeitos dos fármacos , alfa-Glucosidases/farmacocinética , Administração Oral , Adulto , Esquema de Medicação , Sinergismo Farmacológico , Quimioterapia Combinada , Terapia de Reposição de Enzimas/métodos , Feminino , Doença de Depósito de Glicogênio Tipo II/enzimologia , Doença de Depósito de Glicogênio Tipo II/patologia , Humanos , Infusões Intravenosas , Lisossomos/patologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/enzimologia , Músculo Esquelético/patologia , Segurança do Paciente , Resultado do Tratamento , alfa-Glucosidases/sangueRESUMO
Pompe disease is caused by a deficiency in the lysosomal enzyme α-glucosidase, and this leads to glycogen accumulation in the autolysosomes of patient cells. Glycogen storage material is exocytosed at a basal rate in cultured Pompe cells, with one study showing up to 80% is released under specific culture conditions. Critically, exocytosis induction may reduce glycogen storage in Pompe patients, providing the basis for a therapeutic strategy whereby stored glycogen is redirected to an extracellular location and subsequently degraded by circulating amylases. The focus of the current study was to identify compounds capable of inducing rapid glycogen exocytosis in cultured Pompe cells. Here, calcimycin, lysophosphatidylcholine and α-l-iduronidase each significantly increased glycogen exocytosis compared to vehicle-treated controls. The most effective compound, calcimycin, induced exocytosis through a Ca2+-dependent mechanism, although was unable to release a pool of vesicular glycogen larger than the calcimycin-induced exocytic pore. There was reduced glycogen release from Pompe compared to unaffected cells, primarily due to increased granule size in Pompe cells. Drug induced exocytosis therefore shows promise as a therapeutic approach for Pompe patients but strategies are required to enhance the release of large molecular weight glycogen granules.
Assuntos
Calcimicina/farmacologia , Exocitose/efeitos dos fármacos , Doença de Depósito de Glicogênio Tipo II/metabolismo , Glicogênio/metabolismo , Iduronidase/farmacologia , Lisofosfatidilcolinas/farmacologia , Calcimicina/uso terapêutico , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Humanos , Iduronidase/uso terapêutico , Lisofosfatidilcolinas/uso terapêutico , Lisossomos/efeitos dos fármacos , Fagossomos/efeitos dos fármacos , Veículos Farmacêuticos/farmacologiaRESUMO
ABSTRACT Pompe disease (PD) is a potentially lethal illness involving irreversible muscle damage resulting from glycogen storage in muscle fiber and activation of autophagic pathways. A promising therapeutic perspective for PD is enzyme replacement therapy (ERT) with the human recombinant enzyme acid alpha-glucosidase (Myozyme®). The need to organize a diagnostic flowchart, systematize clinical follow-up, and establish new therapeutic recommendations has become vital, as ERT ensures greater patient longevity. A task force of experienced clinicians outlined a protocol for diagnosis, monitoring, treatment, genetic counseling, and rehabilitation for PD patients. The study was conducted under the coordination of REBREPOM, the Brazilian Network for Studies of PD. The meeting of these experts took place in October 2013, at L’Hotel Port Bay in São Paulo, Brazil. In August 2014, the text was reassessed and updated. Given the rarity of PD and limited high-impact publications, experts submitted their views.
RESUMO A doença de Pompe (DP) é uma doença grave, potencialmente letal, devida ao depósito de glicogênio na fibra muscular e ativação de vias autofágicas. Tratamento promissor para a DP é a reposição enzimática com a enzima recombinante humana alfa-glicosidase ácida (rhAGA -Myozyme®). A necessidade de organizar uma propedêutica diagnóstica, sistematizar o seguimento clínico e sedimentar as novas recomendações terapêuticas tornaram-se vitais à medida que o tratamento permite uma maior longevidade aos pacientes. Uma força-tarefa de clínicos experientes no manejo da DP foi constituída para elaborar um protocolo para o diagnóstico, acompanhamento clínico, tratamento, aconselhamento genético, entre outras considerações voltadas ao paciente adulto. O estudo foi realizado sob a coordenação da Rede Brasileira de Estudos da Doença de Pompe (REBREPOM). Diante da raridade da DP e escassez de trabalhos de alto impacto de evidência científica, os especialistas emitiram suas opiniões.
Assuntos
Humanos , Adolescente , Adulto , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Guias de Prática Clínica como Assunto , alfa-Glucosidases/uso terapêutico , Terapia de Reposição de Enzimas , Exame Físico/métodos , Diagnóstico DiferencialRESUMO
UNLABELLED: Enzyme replacement therapy (ERT) with recombinant human acid α-glucosidase (rhGAA) fails to completely reverse muscle weakness in Pompe disease. ß2-agonists enhanced ERT by increasing receptor-mediated uptake of rhGAA in skeletal muscles. PURPOSE: To test the hypothesis that a ß-blocker might reduce the efficacy of ERT, because the action of ß-blockers opposes those of ß2-agonists. METHODS: Mice with Pompe disease were treated with propranolol (a ß-blocker) or clenbuterol in combination with ERT, or with ERT alone. RESULTS: Propranolol-treated mice had decreased weight gain (p<0.01), in comparison with clenbuterol-treated mice. Left ventricular mass was decreased (and comparable to wild-type) in ERT only and clenbuterol-treated groups of mice, and unchanged in propranolol-treated mice. GAA activity increased following either clenbuterol or propranolol in skeletal muscles. However, muscle glycogen was reduced only in clenbuterol-treated mice, not in propranolol-treated mice. Cell-based experiments confirmed that propranolol reduces uptake of rhGAA into Pompe fibroblasts and also demonstrated that the drug induces intracellular accumulation of glycoproteins at higher doses. CONCLUSION: Propranolol, a commonly prescribed ß-blocker, reduced weight, increased left ventricular mass and decreased glycogen clearance in skeletal muscle following ERT. ß-Blockers might therefore decrease the efficacy from ERT in patients with Pompe disease.
Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Propranolol/farmacologia , alfa-Glucosidases/uso terapêutico , Antagonistas Adrenérgicos beta/uso terapêutico , Animais , Células Cultivadas , Antagonismo de Drogas , Avaliação Pré-Clínica de Medicamentos , Fibroblastos/metabolismo , Glicogênio/metabolismo , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Humanos , Camundongos Knockout , Propranolol/uso terapêutico , alfa-Glucosidases/farmacologiaRESUMO
Pompe disease (PD) is a potentially lethal illness involving irreversible muscle damage resulting from glycogen storage in muscle fiber and activation of autophagic pathways. A promising therapeutic perspective for PD is enzyme replacement therapy (ERT) with the human recombinant enzyme acid alpha-glucosidase (Myozyme®). The need to organize a diagnostic flowchart, systematize clinical follow-up, and establish new therapeutic recommendations has become vital, as ERT ensures greater patient longevity. A task force of experienced clinicians outlined a protocol for diagnosis, monitoring, treatment, genetic counseling, and rehabilitation for PD patients. The study was conducted under the coordination of REBREPOM, the Brazilian Network for Studies of PD. The meeting of these experts took place in October 2013, at L'Hotel Port Bay in São Paulo, Brazil. In August 2014, the text was reassessed and updated. Given the rarity of PD and limited high-impact publications, experts submitted their views.
Assuntos
Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II , Guias de Prática Clínica como Assunto , alfa-Glucosidases/uso terapêutico , Adolescente , Adulto , Diagnóstico Diferencial , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/genética , Humanos , Exame Físico/métodosRESUMO
Thermal shift assay can be used for the high-throughput screening of pharmacological chaperones. These drugs are small molecules that bind a mutant protein and stabilize it. We demonstrated the robustness, reproducibility and versatility of the method using two molecules that are in clinical trial for Fabry or Pompe disease, Deoxygalactonojirimycin and N-Butyldeoxynojirimycin, and their target enzymes, lysosomal alpha-galactosidaseA and alpha-glucosidase, as test cases. We assessed the influence of solvents and of scanning rate on the measures. We showed that a value that is equivalent to the melting temperature can be obtained by the first derivatives of raw data. We discuss the advantages of the method and the precaution to be taken in running the experiments.
Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Estabilidade Enzimática/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , alfa-Galactosidase/química , 1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/farmacologia , Doença de Fabry/tratamento farmacológico , Doença de Fabry/enzimologia , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/enzimologia , Humanos , Temperatura , alfa-Galactosidase/antagonistas & inibidoresRESUMO
Pompe disease results from a mutation in the acid α-glucosidase gene leading to lysosomal glycogen accumulation. Respiratory insufficiency is common, and the current U.S. Food and Drug Administration-approved treatment, enzyme replacement, has limited effectiveness. Ampakines are drugs that enhance α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor responses and can increase respiratory motor drive. Recent work indicates that respiratory motor drive can be blunted in Pompe disease, and thus pharmacologic stimulation of breathing may be beneficial. Using a murine Pompe model with the most severe clinical genotype (the Gaa(-/-) mouse), our primary objective was to test the hypothesis that ampakines can stimulate respiratory motor output and increase ventilation. Our second objective was to confirm that neuropathology was present in Pompe mouse medullary respiratory control neurons. The impact of ampakine CX717 on breathing was determined via phrenic and hypoglossal nerve recordings in anesthetized mice and whole-body plethysmography in unanesthetized mice. The medulla was examined using standard histological methods coupled with immunochemical markers of respiratory control neurons. Ampakine CX717 robustly increased phrenic and hypoglossal inspiratory bursting and reduced respiratory cycle variability in anesthetized Pompe mice, and it increased inspiratory tidal volume in unanesthetized Pompe mice. CX717 did not significantly alter these variables in wild-type mice. Medullary respiratory neurons showed extensive histopathology in Pompe mice. Ampakines stimulate respiratory neuromotor output and ventilation in Pompe mice, and therefore they have potential as an adjunctive therapy in Pompe disease.
Assuntos
Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Isoxazóis/farmacologia , Respiração/efeitos dos fármacos , Medicamentos para o Sistema Respiratório/farmacologia , Animais , Tronco Encefálico/patologia , Avaliação Pré-Clínica de Medicamentos , Doença de Depósito de Glicogênio Tipo II/fisiopatologia , Isoxazóis/uso terapêutico , Camundongos da Linhagem 129 , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Nervo Frênico/efeitos dos fármacos , Nervo Frênico/fisiopatologia , Medicamentos para o Sistema Respiratório/uso terapêuticoRESUMO
Lysosomal storage disorders (LSD) are a group of heterogeneous diseases caused by compromised enzyme function leading to multiple organ failure. Therapeutic approaches involve enzyme replacement (ERT), which is effective for a substantial fraction of patients. However, there are still concerns about a number of issues including tissue penetrance, generation of host antibodies against the therapeutic enzyme, and financial aspects, which render this therapy suboptimal for many cases. Treatment with pharmacological chaperones (PC) was recognized as a possible alternative to ERT, because a great number of mutations do not completely abolish enzyme function, but rather trigger degradation in the endoplasmic reticulum. The theory behind PC is that they can stabilize enzymes with remaining function, avoid degradation and thereby ameliorate disease symptoms. We tested several compounds in order to identify novel small molecules that prevent premature degradation of the mutant lysosomal enzymes α-galactosidase A (for Fabry disease (FD)) and acid α-glucosidase (GAA) (for Pompe disease (PD)). We discovered that the expectorant Ambroxol when used in conjunction with known PC resulted in a significant enhancement of mutant α-galactosidase A and GAA activities. Rosiglitazone was effective on α-galactosidase A either as a monotherapy or when administered in combination with the PC 1-deoxygalactonojirimycin. We therefore propose both drugs as potential enhancers of pharmacological chaperones in FD and PD to improve current treatment strategies.
Assuntos
1-Desoxinojirimicina/análogos & derivados , Ambroxol/farmacologia , Ativadores de Enzimas/farmacologia , Lisossomos/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , alfa-Galactosidase/genética , alfa-Glucosidases/genética , 1-Desoxinojirimicina/farmacologia , Acetilcisteína/análogos & derivados , Acetilcisteína/farmacologia , Bezafibrato/farmacologia , Doença de Fabry/tratamento farmacológico , Doença de Fabry/enzimologia , Expressão Gênica , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Doença de Depósito de Glicogênio Tipo II/enzimologia , Células HEK293 , Humanos , Leupeptinas/farmacologia , Lisossomos/metabolismo , Pioglitazona , Plasmídeos/química , Plasmídeos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Estabilidade Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tiazolidinedionas/farmacologia , Transfecção , alfa-Galactosidase/metabolismo , alfa-Glucosidases/metabolismoRESUMO
Pompe disease is an autosomal recessive disorder of glycogen metabolism caused by a deficiency of the lysosomal enzyme acid alpha-glucosidase (GAA). Prior to 2006, therapy was palliative. Severely affected infants with Pompe succumbed to cardiomyopathy or respiratory failure by one year of age. Enzyme replacement therapy (ERT) with alglucosidase alfa (Genzyme, Cambridge, MA, USA) is currently the only approved treatment for Pompe disease which has improved overall survival, ventilator-free survival, cardiomyopathy, and motor development in infants. In patients with late onset Pompe disease, ERT has resulted in disease course stabilization with motor and pulmonary improvements. Factors impacting outcome include age at start of ERT, muscle fiber type, underlying genotype and a multidisciplinary approach to care. This article highlights the lessons learned from infants and adults treated with ERT, limitations of ERT, and the development of adjunctive and alternative therapies, including immune modulation, upregulation of receptor expression, diet and exercise, second-generation recombinant ERT, chaperone therapy, substrate reduction therapy and gene therapy.
Assuntos
Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II/terapia , alfa-Glucosidases/uso terapêutico , Terapia Genética , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Humanos , Imunomodulação , Chaperonas MolecularesRESUMO
Pompe disease is due to a deficiency in acid-α-glucosidase (GAA) and results in debilitating skeletal muscle wasting, characterized by the accumulation of glycogen and autophagic vesicles. Given the role of lysosomes as a platform for mTORC1 activation, we examined mTORC1 activity in models of Pompe disease. GAA-knockdown C2C12 myoblasts and GAA-deficient human skin fibroblasts of infantile Pompe patients were found to have decreased mTORC1 activation. Treatment with the cell-permeable leucine analog L-leucyl-L-leucine methyl ester restored mTORC1 activation. In vivo, Pompe mice also displayed reduced basal and leucine-stimulated mTORC1 activation in skeletal muscle, whereas treatment with a combination of insulin and leucine normalized mTORC1 activation. Chronic leucine feeding restored basal and leucine-stimulated mTORC1 activation, while partially protecting Pompe mice from developing kyphosis and the decline in muscle mass. Leucine-treated Pompe mice showed increased spontaneous activity and running capacity, with reduced muscle protein breakdown and glycogen accumulation. Together, these data demonstrate that GAA deficiency results in reduced mTORC1 activation that is partly responsible for the skeletal muscle wasting phenotype. Moreover, mTORC1 stimulation by dietary leucine supplementation prevented some of the detrimental skeletal muscle dysfunction that occurs in the Pompe disease mouse model.
Assuntos
Suplementos Nutricionais , Dipeptídeos/farmacologia , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Complexos Multiproteicos/metabolismo , Músculo Esquelético/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , alfa-Glucosidases/deficiência , Animais , Linhagem Celular , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Glicogênio/metabolismo , Doença de Depósito de Glicogênio Tipo II/enzimologia , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/patologia , Doença de Depósito de Glicogênio Tipo II/fisiopatologia , Humanos , Insulina/farmacologia , Cifose/enzimologia , Cifose/patologia , Cifose/fisiopatologia , Cifose/prevenção & controle , Lisossomos/efeitos dos fármacos , Lisossomos/enzimologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Músculo Esquelético/enzimologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Atrofia Muscular/enzimologia , Atrofia Muscular/patologia , Atrofia Muscular/fisiopatologia , Atrofia Muscular/prevenção & controle , Mioblastos/efeitos dos fármacos , Mioblastos/enzimologia , Interferência de RNA , Transfecção , alfa-Glucosidases/genéticaRESUMO
Enzyme replacement therapy is currently the only approved treatment for Pompe disease, due to acid α-glucosidase deficiency. Clinical efficacy of this approach is variable, and more effective therapies are needed. We showed in preclinical studies that chaperones stabilize the recombinant enzyme used for enzyme replacement therapy. Here, we evaluated the effects of a combination of enzyme therapy and a chaperone on α-glucosidase activity in Pompe disease patients. α-Glucosidase activity was analyzed by tandem-mass spectrometry in dried blood spots from patients treated with enzyme replacement therapy, either alone or in combination with the chaperone N-butyldeoxynojirimycin given at the time of the enzyme infusion. Thirteen patients with different presentations (3 infantile-onset, 10 late-onset) were enrolled. In 11 patients, the combination treatment resulted in α-glucosidase activities greater than 1.85-fold the activities with enzyme replacement therapy alone. In the whole patient population, α-glucosidase activity was significantly increased at 12 hours (2.19-fold, P = 0.002), 24 hours (6.07-fold, P = 0.001), and 36 hours (3.95-fold, P = 0.003). The areas under the curve were also significantly increased (6.78-fold, P = 0.002). These results suggest improved stability of recombinant α-glucosidase in blood in the presence of the chaperone.
Assuntos
1-Desoxinojirimicina/análogos & derivados , Doença de Depósito de Glicogênio Tipo II/sangue , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases/farmacologia , alfa-Glucosidases/farmacologia , 1-Desoxinojirimicina/farmacologia , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Modelos Animais de Doenças , Teste em Amostras de Sangue Seco , Sinergismo Farmacológico , Terapia de Reposição de Enzimas/métodos , Estabilidade Enzimática , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem , alfa-Glucosidases/sangue , alfa-Glucosidases/uso terapêuticoRESUMO
OBJECTIVE: The metabolic disorder Pompe disease mainly affects the skeletal muscle in adults. The hearing impairment due to stapedius muscle involvement in adult patients is not known. DESIGN: The frequency, severity, and type of hearing impairment was characterized prospectively using pure-tone audiometry, tympanometry, stapedial reflexes, otoacoustic emissions, and brainstem-evoked response audiometry in adult patients on enzyme replacement therapy for genetically confirmed Pompe disease. STUDY SAMPLE: 11 adult patients (median age: 47 years, range: 22-71). RESULTS: Four patients complained about subjective hearing disturbances. Using World Health Organization definition of hearing impairment, abnormal hearing thresholds resulting in mild hearing loss were found in 36% of patients. Compared to normative data (ISO 7029), the hearing threshold was below the median in all but three ears. Stapedial reflexes could not be elicited ipsilateral in 18% and contralateral in 36%. Auditory brainstem responses showed no retrocochlear pathology. CONCLUSIONS: The prevalence of hearing loss slightly exceeded the normative data of the general population. Consistent with previous studies the hearing impairment was usually mild. The percentage of pathological stapedial reflexes exceeded that of matched control subjects and suggests a selective involvement of the stapedius muscle, potentially as a sequela of Pompe disease.