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1.
Brain ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38832897

RESUMO

Cerebral adrenoleukodystrophy (CALD) is an X-linked rapidly progressive demyelinating disease leading to death usually within a few years. The standard of care is hematopoietic stem cell transplantation (HSCT), but many men are not eligible due to age, absence of a matched donor, or lesions of the corticospinal tracts (CST). Based on the ADVANCE study showing that leriglitazone decreases the occurrence of CALD, we treated 13 adult CALD patients (19-67 years of age) either not eligible to HSCT (n= 8) or awaiting HSCT (n= 5). Patients were monitored every 3 months with standardized neurological scores, plasma biomarkers and brain MRI comprising lesion volumetrics and diffusion tensor imaging. The disease stabilized clinically and radiologically in 10 patients with up to 2 years of follow-up. Five patients presented with gadolinium enhancing CST lesions that all turned gadolinium negative and, remarkably, regressed in four patients. Plasma neurofilament light chain levels stabilized in all 10 patients and correlated with lesion load. The two patients who continued to deteriorate were over 60 years of age with prominent cognitive impairment. One patient rapidly died from Covid19. These results suggest that leriglitazone can arrest disease progression in adults with early-stage CALD and may be an alternative treatment to HSCT.

2.
J Transl Med ; 21(1): 756, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884937

RESUMO

BACKGROUND: Rett syndrome is a neuropediatric disease occurring due to mutations in MECP2 and characterized by a regression in the neuronal development following a normal postnatal growth, which results in the loss of acquired capabilities such as speech or purposeful usage of hands. While altered neurotransmission and brain development are the center of its pathophysiology, alterations in mitochondrial performance have been previously outlined, shaping it as an attractive target for the disease treatment. METHODS: We have thoroughly described mitochondrial performance in two Rett models, patients' primary fibroblasts and female Mecp2tm1.1Bird-/+ mice brain, discriminating between different brain areas. The characterization was made according to their bioenergetics function, oxidative stress, network dynamics or ultrastructure. Building on that, we have studied the effect of leriglitazone, a PPARγ agonist, in the modulation of mitochondrial performance. For that, we treated Rett female mice with 75 mg/kg/day leriglitazone from weaning until sacrifice at 7 months, studying both the mitochondrial performance changes and their consequences on the mice phenotype. Finally, we studied its effect on neuroinflammation based on the presence of reactive glia by immunohistochemistry and through a cytokine panel. RESULTS: We have described mitochondrial alterations in Rett fibroblasts regarding both shape and bioenergetic functions, as they displayed less interconnected and shorter mitochondria and reduced ATP production along with increased oxidative stress. The bioenergetic alterations were recalled in Rett mice models, being especially significant in cerebellum, already detectable in pre-symptomatic stages. Treatment with leriglitazone recovered the bioenergetic alterations both in Rett fibroblasts and female mice and exerted an anti-inflammatory effect in the latest, resulting in the amelioration of the mice phenotype both in general condition and exploratory activity. CONCLUSIONS: Our studies confirm the mitochondrial dysfunction in Rett syndrome, setting the differences through brain areas and disease stages. Its modulation through leriglitazone is a potential treatment for this disorder, along with other diseases with mitochondrial involvement. This work constitutes the preclinical necessary evidence to lead to a clinical trial.


Assuntos
Síndrome de Rett , Humanos , Feminino , Camundongos , Animais , Síndrome de Rett/tratamento farmacológico , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Mitocôndrias/metabolismo , Encéfalo , Estresse Oxidativo , Modelos Animais de Doenças
3.
Int J Mol Sci ; 24(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36834611

RESUMO

Increasing evidence suggests that the peroxisome proliferator-activated receptor γ (PPARγ), a member of the nuclear receptor superfamily, plays an important role in physiological processes in the central nervous system (CNS) and is involved in cellular metabolism and repair. Cellular damage caused by acute brain injury and long-term neurodegenerative disorders is associated with alterations of these metabolic processes leading to mitochondrial dysfunction, oxidative stress, and neuroinflammation. PPARγ agonists have demonstrated the potential to be effective treatments for CNS diseases in preclinical models, but to date, most drugs have failed to show efficacy in clinical trials of neurodegenerative diseases including amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease. The most likely explanation for this lack of efficacy is the insufficient brain exposure of these PPARγ agonists. Leriglitazone is a novel, blood-brain barrier (BBB)-penetrant PPARγ agonist that is being developed to treat CNS diseases. Here, we review the main roles of PPARγ in physiology and pathophysiology in the CNS, describe the mechanism of action of PPARγ agonists, and discuss the evidence supporting the use of leriglitazone to treat CNS diseases.


Assuntos
Doenças do Sistema Nervoso Central , Doenças Neurodegenerativas , Humanos , Doenças do Sistema Nervoso Central/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neuroinflamatórias , PPAR gama/metabolismo
4.
Neurobiol Dis ; 148: 105162, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33171227

RESUMO

Friedreich ataxia (FRDA), the most common autosomal recessive ataxia, is characterized by degeneration of the large sensory neurons and spinocerebellar tracts, cardiomyopathy, and increased incidence in diabetes. The underlying pathophysiological mechanism of FRDA, driven by a significantly decreased expression of frataxin (FXN), involves increased oxidative stress, reduced activity of enzymes containing iron­sulfur clusters (ISC), defective energy production, calcium dyshomeostasis, and impaired mitochondrial biogenesis, leading to mitochondrial dysfunction. The peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-activated transcriptional factor playing a key role in mitochondrial function and biogenesis, fatty acid storage, energy metabolism, and antioxidant defence. It has been previously shown that the PPARγ/PPARγ coactivator 1 alpha (PGC-1α) pathway is dysregulated when there is frataxin deficiency, thus contributing to FRDA pathogenesis and supporting the PPARγ pathway as a potential therapeutic target. Here we assess whether MIN-102 (INN: leriglitazone), a novel brain penetrant and orally bioavailable PPARγ agonist with an improved profile for central nervous system (CNS) diseases, rescues phenotypic features in cellular and animal models of FRDA. In frataxin-deficient dorsal root ganglia (DRG) neurons, leriglitazone increased frataxin protein levels, reduced neurite degeneration and α-fodrin cleavage mediated by calpain and caspase 3, and increased survival. Leriglitazone also restored mitochondrial membrane potential and partially reversed decreased levels of mitochondrial Na+/Ca2+ exchanger (NCLX), resulting in an improvement of mitochondrial functions and calcium homeostasis. In frataxin-deficient primary neonatal cardiomyocytes, leriglitazone prevented lipid droplet accumulation without increases in frataxin levels. Furthermore, leriglitazone improved motor function deficit in YG8sR mice, a FRDA mouse model. In agreement with the role of PPARγ in mitochondrial biogenesis, leriglitazone significantly increased markers of mitochondrial biogenesis in FRDA patient cells. Overall, these results suggest that targeting the PPARγ pathway by leriglitazone may provide an efficacious therapy for FRDA increasing the mitochondrial function and biogenesis that could increase frataxin levels in compromised frataxin-deficient DRG neurons. Alternately, leriglitazone improved the energy metabolism by increasing the fatty acid ß-oxidation in frataxin-deficient cardiomyocytes without elevation of frataxin levels. This could be linked to a lack of significant mitochondrial biogenesis and cardiac hypertrophy. The results reinforced the different tissue requirement in FRDA and the pleiotropic effects of leriglitazone that could be a promising therapy for FRDA.


Assuntos
Ataxia de Friedreich/metabolismo , Proteínas de Ligação ao Ferro/efeitos dos fármacos , Gotículas Lipídicas/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , PPAR gama/agonistas , Tiazolidinedionas/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Ataxia de Friedreich/patologia , Ataxia de Friedreich/fisiopatologia , Humanos , Proteínas de Ligação ao Ferro/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Neuritos/efeitos dos fármacos , Neuritos/patologia , Neurônios/metabolismo , Neurônios/patologia , Ratos , Frataxina
5.
CPT Pharmacometrics Syst Pharmacol ; 13(6): 982-993, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38549500

RESUMO

Leriglitazone is a unique peroxisome proliferator-activated receptor-gamma (PPARγ) agonist that crosses the blood-brain barrier in humans and clinical trials have shown evidence of efficacy in neurodegenerative diseases. At clinical doses which are well-tolerated, leriglitazone reaches the target central nervous system (CNS) concentrations that are needed for PPARγ engagement and efficacy; PPARγ engagement is also supported by clinical and anti-inflammatory biomarker changes in the Cerebrospinal fluid in the CNS. Plasma pharmacokinetics (PK) of leriglitazone were determined in a phase 1 study in male healthy volunteers comprising a single ascending dose (SAD) and a multiple ascending dose (MAD) at oral doses of 30, 90, and 270 mg and 135 and 270 mg, respectively. Leriglitazone was rapidly absorbed with no food effect on overall exposure and showed a linear PK profile with dose-exposure correlation. A physiologically based pharmacokinetic (PBPK) model was developed for leriglitazone based on phase 1 data (SAD part) and incorporated CYP3A4 (fmCYP3A4 = 24%) and CYP2C8-mediated (fmCYP2C8 = 45%) metabolism, as well as biliary clearance (feBIL = 19.5%) derived from in vitro data, and was verified by comparing the observed versus predicted concentration-time profiles from the MAD part. The PBPK model was prospectively applied to predict the starting pediatric doses and was preliminarily verified with data from five pediatric patients.


Assuntos
Relação Dose-Resposta a Droga , Modelos Biológicos , Tiazolidinedionas , Humanos , Masculino , Criança , Tiazolidinedionas/farmacocinética , Tiazolidinedionas/administração & dosagem , Tiazolidinedionas/sangue , Adulto , Adulto Jovem , PPAR gama/agonistas , Adolescente , Administração Oral , Voluntários Saudáveis
6.
Pharmaceutics ; 15(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36678831

RESUMO

The novel brain-penetrant peroxisome proliferator-activated receptor gamma agonist leriglitazone, previously validated for other rare neurodegenerative diseases, is a small molecule that acts as a regulator of mitochondrial function and exerts neuroprotective, anti-oxidative and anti-inflammatory effects. Herein, we tested whether leriglitazone can be effective in ameliorating the mitochondrial defects that characterize an hiPS-derived model of Pantothenate kinase-2 associated Neurodegeneration (PKAN). PKAN is caused by a genetic alteration in the mitochondrial enzyme pantothenate kinase-2, whose function is to catalyze the first reaction of the CoA biosynthetic pathway, and for which no effective cure is available. The PKAN hiPS-derived astrocytes are characterized by mitochondrial dysfunction, cytosolic iron deposition, oxidative stress and neurotoxicity. We monitored the effect of leriglitazone in comparison with CoA on hiPS-derived astrocytes from three healthy subjects and three PKAN patients. The treatment with leriglitazone did not affect the differentiation of the neuronal precursor cells into astrocytes, and it improved the viability of PKAN cells and their respiratory activity, while diminishing the iron accumulation similarly or even better than CoA. The data suggest that leriglitazone is well tolerated in this cellular model and could be considered a beneficial therapeutic approach in the treatment of PKAN.

7.
Lancet Neurol ; 22(2): 127-136, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36681445

RESUMO

BACKGROUND: Adult patients with adrenoleukodystrophy have a poor prognosis owing to development of adrenomyeloneuropathy. Additionally, a large proportion of patients with adrenomyeloneuropathy develop life-threatening progressive cerebral adrenoleukodystrophy. Leriglitazone is a novel selective peroxisome proliferator-activated receptor gamma agonist that regulates expression of key genes that contribute to neuroinflammatory and neurodegenerative processes implicated in adrenoleukodystrophy disease progression. We aimed to assess the effect of leriglitazone on clinical, imaging, and biochemical markers of disease progression in adults with adrenomyeloneuropathy. METHODS: ADVANCE was a 96-week, randomised, double-blind, placebo-controlled, phase 2-3 trial done at ten hospitals in France, Germany, Hungary, Italy, the Netherlands, Spain, the UK, and the USA. Ambulatory men aged 18-65 years with adrenomyeloneuropathy without gadolinium enhancing lesions suggestive of progressive cerebral adrenoleukodystrophy were randomly assigned (2:1 without stratification) to receive daily oral suspensions of leriglitazone (150 mg starting dose; between baseline and week 12, doses were increased or decreased to achieve plasma concentrations of 200 µg·h/mL [SD 20%]) or placebo by means of an interactive response system and a computer-generated sequence. Investigators and patients were masked to group assignment. The primary efficacy endpoint was change from baseline in the Six-Minute Walk Test distance at week 96, analysed in the full-analysis set by means of a mixed model for repeated measures with restricted maximum likelihood and baseline value as a covariate. Adverse events were also assessed in the full-analysis set. This study was registered with ClinicalTrials.gov, NCT03231878; the primary study is complete; patients had the option to continue treatment in an open-label extension, which is ongoing. FINDINGS: Between Dec 8, 2017, and Oct 16, 2018, of 136 patients screened, 116 were randomly assigned; 62 [81%] of 77 patients receiving leriglitazone and 34 [87%] of 39 receiving placebo completed treatment. There was no between-group difference in the primary endpoint (mean [SD] change from baseline leriglitazone: -27·7 [41·4] m; placebo: -30·3 [60·5] m; least-squares mean difference -1·2 m; 95% CI -22·6 to 20·2; p=0·91). The most common treatment emergent adverse events in both the leriglitazone and placebo groups were weight gain (54 [70%] of 77 vs nine [23%] of 39 patients, respectively) and peripheral oedema (49 [64%] of 77 vs seven [18%] of 39). There were no deaths. Serious treatment-emergent adverse events occurred in 14 (18%) of 77 patients receiving leriglitazone and ten (26%) of 39 patients receiving placebo. The most common serious treatment emergent adverse event, clinically progressive cerebral adrenoleukodystrophy, occurred in six [5%] of 116 patients, all of whom were in the placebo group. INTERPRETATION: The primary endpoint was not met, but leriglitazone was generally well tolerated and rates of adverse events were in line with the expected safety profile for this drug class. The finding that cerebral adrenoleukodystrophy, a life-threatening event for patients with adrenomyeloneuropathy, occurred only in patients in the placebo group supports further investigation of whether leriglitazone might slow the progression of cerebral adrenoleukodystrophy. FUNDING: Minoryx Therapeutics.


Assuntos
Adrenoleucodistrofia , Adulto , Masculino , Humanos , Resultado do Tratamento , Adrenoleucodistrofia/tratamento farmacológico , França , Método Duplo-Cego , Progressão da Doença
8.
Neurol Genet ; 8(6): e200034, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36524101

RESUMO

Background and Objectives: Friedreich ataxia (FRDA) is an autosomal recessive ataxia with no approved treatments. Leriglitazone is a selective peroxisome proliferator-activated receptor γ agonist that crosses the blood-brain barrier and, in preclinical models, improved mitochondrial function and energy production. We assessed effects of leriglitazone in patients with FRDA in a proof-of-concept study. Methods: In this double-blind, randomized controlled trial, eligible participants (age 12-60 years) had genetically confirmed FRDA, a Scale for the Assessment and Rating of Ataxia (SARA) total score <25, and a SARA item 1 score of 2-6, inclusive. Key exclusion criteria were age at FRDA onset ≥25 years and history of cardiac dysfunction. Participants were randomly assigned (2:1) to receive a daily, oral, individualized dose of leriglitazone or placebo for 48 weeks. The primary endpoint was the change from baseline to week 48 in spinal cord area (C2-C3) (measured by MRI). Secondary endpoints included the change from baseline to week 48 in iron accumulation in the dentate nucleus (quantitative susceptibility mapping) and total N-acetylaspartate to myo-inositol (tNAA/mIns) ratio. Results: Overall, 39 patients were enrolled (mean age 24 years; 43.6% women; mean time since symptom onset 10.5 years): 26 patients received leriglitazone (20 completed) and 13 received placebo (12 completed). There was no difference between groups in spinal cord area from baseline to week 48 (least-squares [LS] mean change [standard error (SE)]: leriglitazone, -0.39 [0.55] mm2; placebo, 0.08 [0.72] mm2; p = 0.61). Iron accumulation in the dentate nucleus was greater with placebo (LS mean change [SE]: leriglitazone, 0.10 [1.33] ppb; placebo, 4.86 [1.84] ppb; p = 0.05), and a numerical difference was seen in tNAA/mIns ratio (LS mean change [SE]: leriglitazone, 0.03 [0.02]; placebo, -0.02 [0.03]; p = 0.25). The most frequent adverse event was peripheral edema (leriglitazone 73.1%, placebo 0%). Discussion: The primary endpoint of change in spinal cord area was not met. Secondary endpoints provide evidence supporting proof of concept for leriglitazone mode of action and, with acceptable safety data, support larger studies in patients with FRDA. Trial Registration Information: ClinicalTrials.gov: NCT03917225; EudraCT: 2018-004405-64; submitted April 17, 2019; first patient enrolled April 2, 2019. clinicaltrials.gov/ct2/show/NCT03917225?term=NCT03917225&draw=2&rank=1. Classification of Evidence: This study provides Class I evidence that individualized dosing of leriglitazone, compared with placebo, is not associated with changes in spinal cord area in patients with FRDA.

9.
Sci Transl Med ; 13(596)2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078742

RESUMO

X-linked adrenoleukodystrophy (X-ALD), a potentially fatal neurometabolic disorder with no effective pharmacological treatment, is characterized by clinical manifestations ranging from progressive spinal cord axonopathy [adrenomyeloneuropathy (AMN)] to severe demyelination and neuroinflammation (cerebral ALD-cALD), for which molecular mechanisms are not well known. Leriglitazone is a recently developed brain penetrant full PPARγ agonist that could modulate multiple biological pathways relevant for neuroinflammatory and neurodegenerative diseases, and particularly for X-ALD. We found that leriglitazone decreased oxidative stress, increased adenosine 5'-triphosphate concentration, and exerted neuroprotective effects in primary rodent neurons and astrocytes after very long chain fatty acid-induced toxicity simulating X-ALD. In addition, leriglitazone improved motor function; restored markers of oxidative stress, mitochondrial function, and inflammation in spinal cord tissues from AMN mouse models; and decreased the neurological disability in the EAE neuroinflammatory mouse model. X-ALD monocyte-derived patient macrophages treated with leriglitazone were less skewed toward an inflammatory phenotype, and the adhesion of human X-ALD monocytes to brain endothelial cells decreased after treatment, suggesting the potential of leriglitazone to prevent the progression to pathologically disrupted blood-brain barrier. Leriglitazone increased myelin debris clearance in vitro and increased myelination and oligodendrocyte survival in demyelination-remyelination in vivo models, thus promoting remyelination. Last, leriglitazone was clinically tested in a phase 1 study showing central nervous system target engagement (adiponectin increase) and changes on inflammatory biomarkers in plasma and cerebrospinal fluid. The results of our study support the use of leriglitazone in X-ALD and, more generally, in other neuroinflammatory and neurodegenerative conditions.


Assuntos
Adrenoleucodistrofia , PPAR gama/agonistas , Adrenoleucodistrofia/tratamento farmacológico , Encéfalo , Células Endoteliais , Humanos , Oligodendroglia
10.
PLoS One ; 15(5): e0233468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469975

RESUMO

Transcription disequilibria are characteristic of many neurodegenerative diseases. The activity-evoked transcription of immediate early genes (IEGs), important for neuronal plasticity, memory and behavior, is altered in CNS diseases and governed by epigenetic modulation. KDM1A, a histone 3 lysine 4 demethylase that forms part of transcription regulation complexes, has been implicated in the control of IEG transcription. Here we report the development of vafidemstat (ORY-2001), a brain penetrant inhibitor of KDM1A and MAOB. ORY-2001 efficiently inhibits brain KDM1A at doses suitable for long term treatment, and corrects memory deficit as assessed in the novel object recognition testing in the Senescence Accelerated Mouse Prone 8 (SAMP8) model for accelerated aging and Alzheimer's disease. Comparison with a selective KDM1A or MAOB inhibitor reveals that KDM1A inhibition is key for efficacy. ORY-2001 further corrects behavior alterations including aggression and social interaction deficits in SAMP8 mice and social avoidance in the rat rearing isolation model. ORY-2001 increases the responsiveness of IEGs, induces genes required for cognitive function and reduces a neuroinflammatory signature in SAMP8 mice. Multiple genes modulated by ORY-2001 are differentially expressed in Late Onset Alzheimer's Disease. Most strikingly, the amplifier of inflammation S100A9 is highly expressed in LOAD and in the hippocampus of SAMP8 mice, and down-regulated by ORY-2001. ORY-2001 is currently in multiple Phase IIa studies.


Assuntos
Inibidores Enzimáticos/farmacologia , Histona Desmetilases/antagonistas & inibidores , Transtornos da Memória/tratamento farmacológico , Inibidores da Monoaminoxidase/farmacologia , Oxidiazóis/farmacologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/psicologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/psicologia , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Epigênese Genética/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacocinética , Oxidiazóis/química , Oxidiazóis/farmacocinética , Ratos , Ratos Sprague-Dawley
11.
Cancer Cell ; 33(3): 495-511.e12, 2018 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-29502954

RESUMO

The lysine-specific demethylase KDM1A is a key regulator of stem cell potential in acute myeloid leukemia (AML). ORY-1001 is a highly potent and selective KDM1A inhibitor that induces H3K4me2 accumulation on KDM1A target genes, blast differentiation, and reduction of leukemic stem cell capacity in AML. ORY-1001 exhibits potent synergy with standard-of-care drugs and selective epigenetic inhibitors, reduces growth of an AML xenograft model, and extends survival in a mouse PDX (patient-derived xenograft) model of T cell acute leukemia. Surrogate pharmacodynamic biomarkers developed based on expression changes in leukemia cell lines were translated to samples from patients treated with ORY-1001. ORY-1001 is a selective KDM1A inhibitor in clinical trials and is currently being evaluated in patients with leukemia and solid tumors.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Histona Desmetilases/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/metabolismo , Modelos Animais de Doenças , Histona Desmetilases/antagonistas & inibidores , Histona Desmetilases/genética , Humanos , Leucemia Mieloide Aguda/genética , Camundongos , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
12.
Biochem Pharmacol ; 71(1-2): 32-41, 2005 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-16298346

RESUMO

In a search for new anticancer agents, we have identified serratamolide (AT514), a cyclodepsipeptide from Serratia marcescens 2170 that induces cell cycle arrest and apoptosis in various cancer cell lines. A cell viability assay showed that the concentrations that cause 50% inhibition (IC50) in human cancer cell lines range from 5.6 to 11.5 microM depending on the cell line. Flow cytometry analysis revealed that AT514 caused cell cycle arrest in G0/G1 or cell death, depending on the cell type and the length of time for which the cells were exposed to the drug. Subsequent studies revealed that AT514-induced cell death is caused by apoptosis, as indicated by caspases activation (8, 9, 2 and 3) and cleavage of poly (ADP-ribose) polymerase (PARP), release of cytochrome c and apoptosis inducing factor (AIF) from mitochondria, and the appearance of apoptotic bodies and DNA laddering. Alterations in protein levels of Bcl-2 family members might be involved in the mitochondrial disruption observed. AT514 induced p53 accumulation in wild-type p53 cells but cell death was observed in both deficient and wild-type p53 cells. Our results indicate that AT514 induces cell cycle arrest and apoptosis in breast cancer cells irrespectively of p53 status, suggesting that it might represent a potential new chemotherapeutic agent.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Depsipeptídeos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos/isolamento & purificação , Neoplasias da Mama/enzimologia , Caspases/metabolismo , Linhagem Celular Tumoral , Depsipeptídeos/isolamento & purificação , Ativação Enzimática , Humanos , Membranas Intracelulares/metabolismo , Mitocôndrias/efeitos dos fármacos
13.
Toxicol Sci ; 85(2): 870-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15788728

RESUMO

Prodigiosin is a red pigment produced by Serratia marcescens with apoptotic activity. We examined the mechanism of action of this tripyrrole alkaloid, focusing on its interaction with DNA and its ability to inhibit both topoisomerase I and topoisomerase II. We also evaluated the DNA damage induced in cancer cell lines. Prodigiosin-DNA intercalation was analyzed using a competition dialysis assay with different DNA base sequences. Topoisomerase I and II inhibition was studied in vitro by a cleavage assay, and in cultured cells, by analysis of its ability to form covalent complexes. Furthermore, we analyzed DNA damage by pulse-field gel electrophoresis and by immunocytochemistry. Apoptosis inducing factor (AIF)/phospho-H2AX (p-H2AX) double labeling by confocal microscopy was performed to determine the possible implication of AIF in the prodigiosin-DNA damage. Finally, we studied the ability of this drug to induce copper-mediated DNA damage at different pH by a DNA cleavage assay. Our results demonstrate prodigiosin-DNA interaction in vitro and in cultured cells. It involves prodigiosin-DNA intercalation, with some preference for the alternating base pairs but with no discrimination between AT or CG sequences, dual abolition of topoisomerase I and II activity and, as consequence, DNA cleavage. Prodigiosin-DNA damage is independent of AIF. Furthermore, we found that copper-mediated cleavage activity is associated with pH (occurring at pH 6.8 rather than pH 7.4) and with the Cu(2+) ion concentration. These results indicate DNA a therapeutic target for prodigiosin and could explain the apoptosis mechanism of action induced by this antineoplastic drug.


Assuntos
Antibióticos Antineoplásicos/farmacologia , DNA/efeitos dos fármacos , Inibidores Enzimáticos , Prodigiosina/farmacologia , Inibidores da Topoisomerase I , Inibidores da Topoisomerase II , Ligação Competitiva/efeitos dos fármacos , Southern Blotting , Linhagem Celular Tumoral , Células Cultivadas , Cobre/farmacologia , DNA/metabolismo , Diálise , Humanos , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Substâncias Intercalantes/farmacologia , Células Jurkat , Plasmídeos/efeitos dos fármacos , Plasmídeos/genética
14.
BMC Struct Biol ; 4: 7, 2004 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-15180901

RESUMO

BACKGROUND: Arabidopsis thaliana copper metallochaperone CCH is a functional homologue of yeast antioxidant ATX1, involved in cytosolic copper transport. In higher plants, CCH has to be transported to specialised cells through plasmodesmata, being the only metallochaperone reported to date that leaves the cell where it is synthesised. CCH has two different domains, the N-terminal domain conserved among other copper-metallochaperones and a C-terminal domain absent in all the identified non-plant metallochaperones. The aim of the present study was the biochemical and biophysical characterisation of the C-terminal domain of the copper metallochaperone CCH. RESULTS: The conformational behaviour of the isolated C-domain in solution is complex and implies the adoption of mixed conformations in different environments. The ionic self-complementary peptide KTEAETKTEAKVDAKADVE, derived from the C-domain of CCH, adopts and extended conformation in solution with a high content in beta-sheet structure that induces a pH-dependent fibril formation. Freeze drying electron microscopy studies revealed the existence of well ordered amyloid-like fibrils in preparations from both the C-domain and its derivative peptide. CONCLUSION: A number of proteins related with copper homeostasis have a high tendency to form fibrils. The determinants for fibril formation, as well as the possible physiological role are not fully understood. Here we show that the plant exclusive C-domain of the copper metallochaperone CCH has conformational plasticity and forms fibrils at defined experimental conditions. The putative influence of these properties with plant copper delivery will be addressed in the future.


Assuntos
Proteínas de Arabidopsis/química , Cobre/metabolismo , Chaperonas Moleculares/química , Concentração Osmolar , Peptídeos/química , Proteína Amiloide A Sérica/química , Sequência de Aminoácidos , Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Transporte Biológico/fisiologia , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/fisiologia , Dados de Sequência Molecular , Peptídeos/metabolismo , Peptídeos/fisiologia , Conformação Proteica , Estrutura Secundária de Proteína/fisiologia
15.
Pharm Pat Anal ; 2(1): 109-24, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24236974

RESUMO

Pharmacological chaperone therapy (PCT) is a rather new approach consisting in targeting incorrectly folded proteins by small molecules, thus, facilitating the correct folding of the protein and inducing a recovery of its functionality. Many diseases result from mutations on specific genes; this patent review focuses on those pathologies where PCT has a potential application for enzymatic enhancement. Rare diseases are the main area where PCT has been applied and the most advanced compounds are aiming to cure lysosomal storage disorders such as Fabry, Pompe or Gaucher. Until now, most compounds used as pharmacological chaperones were based on substrate-like chemical structures but recently new nonsubstrate-like and non-inhibitory compounds have been disclosed for Gaucher and Pompe diseases. This initiates a new era for pharmacological chaperones with more diverse chemical structures and binding modes. This review covers the patents relating to enzyme enhancement on pharmacological chaperone therapy. Only an update is presented for Gaucher disease, where PCT is highly applied and recently reviewed.


Assuntos
Terapia Enzimática , Doenças por Armazenamento dos Lisossomos/tratamento farmacológico , Chaperonas Moleculares/uso terapêutico , Animais , Fibrose Cística/tratamento farmacológico , Humanos , Fenilcetonúrias/tratamento farmacológico
17.
Chembiochem ; 7(7): 1105-13, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16795116

RESUMO

The applied interaction of synthetic molecules with defined regions of protein surfaces is an emerging strategy for the modulation of protein activity and/or stability. In spite of recent advances, the design of these molecules is not trivial. Among the most challenging aspects in designing these compounds is that they must compete with water molecules for interaction with polar patches of protein surfaces. Herein is reported the preparation of an arginine-rich peptide that interacts in aqueous solution with a very hydrophilic patch at the surface of the tetramerization domain of the tumor suppressor protein p53. The interaction has been studied by several complementary techniques. By using this peptide as a template, a library of peptides has been prepared and evaluated in order to examine the different factors that contribute to the recognition event. The conclusions extracted from this work could be useful for the design of ligands directed at highly hydrophilic protein surface patches.


Assuntos
Biblioteca de Peptídeos , Peptídeos/química , Proteína Supressora de Tumor p53/química , Sítios de Ligação , Células HeLa , Humanos , Ligantes , Ligação Proteica , Estrutura Terciária de Proteína
18.
J Comput Aided Mol Des ; 19(8): 585-601, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16267689

RESUMO

One of the goals of computational chemists is to automate the de novo design of bioactive molecules. Despite significant advances in computational approaches to ligand design and binding energy evaluation, novel procedures for ligand design are required. Evolutionary computation provides a new approach to this design endeavor. We propose an evolutionary tool for de novo peptide design, based on the evaluation of energies for peptide binding to a user-defined protein surface patch. Special emphasis has been placed on the evaluation of the proposed peptides, leading to two different evaluation heuristics. The software developed was successfully tested on the design of ligands for the proteins prolyl oligopeptidase, p53, and DNA gyrase.


Assuntos
Algoritmos , Desenho de Fármacos , Modelos Moleculares , Peptídeos/química , Sequência de Aminoácidos , Animais , Teorema de Bayes , Sítios de Ligação/genética , DNA Girase/química , DNA Girase/genética , DNA Girase/metabolismo , Evolução Molecular , Antígenos H-2/química , Antígenos H-2/genética , Antígenos H-2/metabolismo , Humanos , Ligantes , Camundongos , Peptídeos/genética , Peptídeos/metabolismo , Prolil Oligopeptidases , Ligação Proteica , Conformação Proteica , Serina Endopeptidases/química , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Software , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
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