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1.
Pharmaceutics ; 16(6)2024 May 24.
Article in English | MEDLINE | ID: mdl-38931834

ABSTRACT

Huntington's disease (HD) is a monogenic neurodegenerative disorder caused by a cytosine-adenine-guanine (CAG) trinucleotide repeat expansion in the HTT gene. There are no cures for HD, but the genetic basis of this disorder makes gene therapy a viable approach. Adeno-associated virus (AAV)-miRNA-based therapies have been demonstrated to be effective in lowering HTT mRNA; however, the blood-brain barrier (BBB) poses a significant challenge for gene delivery to the brain. Delivery strategies include direct injections into the central nervous system, which are invasive and can result in poor diffusion of viral particles through the brain parenchyma. Focused ultrasound (FUS) is an alternative approach that can be used to non-invasively deliver AAVs by temporarily disrupting the BBB. Here, we investigate FUS-mediated delivery of a single-stranded AAV9 bearing a cDNA for GFP in 2-month-old wild-type mice and the zQ175 HD mouse model at 2-, 6-, and 12-months. FUS treatment improved AAV9 delivery for all mouse groups. The delivery efficacy was similar for all WT and HD groups, with the exception of the zQ175 12-month cohort, where we observed decreased GFP expression. Astrocytosis did not increase after FUS treatment, even within the zQ175 12-month group exhibiting higher baseline levels of GFAP expression. These findings demonstrate that FUS can be used to non-invasively deliver an AAV9-based gene therapy to targeted brain regions in a mouse model of Huntington's disease.

3.
Front Hum Neurosci ; 17: 1241589, 2023.
Article in English | MEDLINE | ID: mdl-37780963

ABSTRACT

Associations between reading performance and duration perception have been found both for domain-general and speech-specific duration perception. However, research seems limited to children and, critically, the predictive value of the two duration perception modalities has not been compared so far. In the present study we compared the weight of domain-general (comparison of time intervals defined by beeps) vs. speech-specific duration perception (pre-attentive EEG responses to consonants with different durations) as statistical predictors of reading in a sample of 46 neurotypical adults (18-43 years old) with 13 years of schooling on average. Reading included word and pseudoword decoding, as well as reading comprehension. We ran one regression model with domain-general and speech-specific duration perception as predictors for each of the three reading skills. Pseudoword decoding was the only reading skill that was significantly predicted by duration perception, and this happened for domain-general duration perception only. A complementary analysis adding 26 typically developing and 24 dyslexic adults to the main sample (n = 96 in total) showed the same pattern of results in dyslexics, but not in added controls. Our findings strengthen the idea that duration perception is important to phonological encoding and its use in grapheme-to-phoneme conversion, given that only pseudoword decoding was predicted by the interval comparison task. The irrelevance of speech-specific duration perception tones down the possibility that accurately perceiving the length of speech sounds is crucial to skilled reading.

5.
Sci Rep ; 13(1): 12873, 2023 08 08.
Article in English | MEDLINE | ID: mdl-37553469

ABSTRACT

Dyslexics underperform controls in estimating and comparing time intervals defined by visual stimuli. Accuracy in vision-based duration perception requires efficient processing of visual events because these will define the onset and offset of time intervals. Since dyslexics have difficulties processing dimensions of visual stimuli like luminance contrasts and motion, we do not know the extent to which these visual deficits are responsible for their difficulties in judging time intervals. To address this gap, we asked adults with dyslexia and matched controls to perform an interval comparison task involving five different types of visual stimuli with different levels of challenge regarding luminance contrasts and motion. If the expected disadvantage of dyslexics in visual duration perception increased for stimuli requiring increased luminance or motion processing, this would indicate that visual processing plays a role. Results showed poorer time discrimination in dyslexics, but this disadvantage did not change according to stimulus type. Complementary analyses of oculomotor behavior during the task suggested that the poorer timing performance of dyslexics may relate instead to attention and/or engagement with the task. Our findings strengthen the evidence in favor of visual duration perception deficits in dyslexia, but not the hypothesis that these result from purely visual problems.


Subject(s)
Dyslexia , Motion Perception , Time Perception , Adult , Humans , Visual Perception , Vision Disorders
6.
Brain Sci ; 13(3)2023 Mar 04.
Article in English | MEDLINE | ID: mdl-36979251

ABSTRACT

Prosodic phrasing is the segmentation of utterances into prosodic words, phonological phrases (smaller units) and intonational phrases (larger units) based on acoustic cues-pauses, pitch changes and pre-boundary lengthening. The perception of prosodic boundaries is characterized by a positive event-related potential (ERP) component, temporally aligned with phrase boundaries-the Closure Positive Shift (CPS). The role of pre-boundary lengthening in boundary perception is still a matter of debate: while studies on phonological phrase boundaries indicate that all three cues contribute equally, approaches to intonational phrase boundaries highlight the pause as the most powerful cue. Moreover, all studies used explicit boundary recognition tasks, and it is unknown how pre-boundary lengthening works in implicit prosodic processing tasks, characteristic of real-life contexts. In this study, we examined the effects of pre-boundary lengthening (original, short, and long) on the EEG responses to intonational phrase boundaries (CPS effect) in European Portuguese, using an implicit task. Both original and short versions showed equivalent CPS effects, while the long set did not elicit the effect. This suggests that pre-boundary lengthening does not contribute to improved perception of boundaries in intonational phrases (longer units), possibly due to memory and attention-related constraints.

7.
Article in English | MEDLINE | ID: mdl-36361311

ABSTRACT

Multiple sclerosis (MS) is a demyelinating chronic disease that has had increasing prevalence over the last years. We have investigated whether the perceived quality of life is reduced in multiple sclerosis patients compared to control participants with a cross-sectional approach, and how it relates to sociodemographic, clinical, and psychosocial variables in MS with multiple regression. To that end, a group of MS patients (n = 50) and a control group (n = 50) that was matched for age and education level filled in the WHOQOL-BREF (perceived quality of life across four domains) and a sociodemographic questionnaire. The participants in the MS group also filled in a clinical questionnaire and three instruments measuring psychosocial variables (the DASS-21 for depression, anxiety, and stress, the Brief-COPE for coping skills, and the Meaning in Life Scale). The results showed that the perceived quality of life was lower in the MS group than in the control group. Multiple regression models incorporating the variables that showed significant correlations with the quality of life indicated that age, professional status, recovery from relapses, depression, active coping, and meaning in life predicted at least one domain of the quality of life. Meaning in life predicted the quality of life in all four of the domains. Although the quality of life in MS is linked to multiple biopsychosocial variables, meaning in life seems crucial.


Subject(s)
Multiple Sclerosis , Quality of Life , Humans , Quality of Life/psychology , Multiple Sclerosis/psychology , Anxiety/epidemiology , Surveys and Questionnaires , Adaptation, Psychological
8.
Stud Health Technol Inform ; 294: 817-818, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35612215

ABSTRACT

We explored whether a multi-component approach - using a digital health device, the easypod™ auto-injector, the 'MySupport' patient support programme (PSP) and a Patient Activation Measure® (PAM®) - could improve adherence in patients receiving recombinant human growth hormone (r-hGH). A 13-item PAM was used to assess caregiver self-reported knowledge, resulting in two PAM scores for 88 patients at four UK hospitals after an average of 5.6 months. Most patients improved their PAM score by ≥1 level (43%) or maintained it (>-1 and <1; 21%). In parallel, 74% of patients maintained (-5 to +5%) or improved (≥5%) their adherence. Further studies are required to evaluate a multi-component approach to adherence in a larger population and for a longer duration.


Subject(s)
Human Growth Hormone , Caregivers , Growth Disorders/epidemiology , Human Growth Hormone/therapeutic use , Humans , Medication Adherence , Recombinant Proteins/therapeutic use , Self Report
9.
Nat Med ; 28(2): 251-259, 2022 02.
Article in English | MEDLINE | ID: mdl-35145305

ABSTRACT

Tay-Sachs disease (TSD) is an inherited neurological disorder caused by deficiency of hexosaminidase A (HexA). Here, we describe an adeno-associated virus (AAV) gene therapy expanded-access trial in two patients with infantile TSD (IND 18225) with safety as the primary endpoint and no secondary endpoints. Patient TSD-001 was treated at 30 months with an equimolar mix of AAVrh8-HEXA and AAVrh8-HEXB administered intrathecally (i.t.), with 75% of the total dose (1 × 1014 vector genomes (vg)) in the cisterna magna and 25% at the thoracolumbar junction. Patient TSD-002 was treated at 7 months by combined bilateral thalamic (1.5 × 1012 vg per thalamus) and i.t. infusion (3.9 × 1013 vg). Both patients were immunosuppressed. Injection procedures were well tolerated, with no vector-related adverse events (AEs) to date. Cerebrospinal fluid (CSF) HexA activity increased from baseline and remained stable in both patients. TSD-002 showed disease stabilization by 3 months after injection with ongoing myelination, a temporary deviation from the natural history of infantile TSD, but disease progression was evident at 6 months after treatment. TSD-001 remains seizure-free at 5 years of age on the same anticonvulsant therapy as before therapy. TSD-002 developed anticonvulsant-responsive seizures at 2 years of age. This study provides early safety and proof-of-concept data in humans for treatment of patients with TSD by AAV gene therapy.


Subject(s)
Tay-Sachs Disease , Anticonvulsants , Dependovirus/genetics , Genetic Therapy , Humans , Tay-Sachs Disease/genetics , Tay-Sachs Disease/therapy
11.
Brain ; 145(2): 655-669, 2022 04 18.
Article in English | MEDLINE | ID: mdl-34410345

ABSTRACT

GM1 gangliosidosis is a fatal neurodegenerative disease caused by a deficiency of lysosomal ß-galactosidase. In its most severe form, GM1 gangliosidosis causes death by 4 years of age, and no effective treatments exist. Previous work has shown that injection of the brain parenchyma with an adeno-associated viral (AAV) vector provides pronounced therapeutic benefit in a feline GM1 model. To develop a less invasive treatment for the brain and increase systemic biodistribution, intravenous injection of AAV9 was evaluated. AAV9 expressing feline ß-galactosidase was intravenously administered at 1.5×1013 vector genomes/kg body weight to six GM1 cats at ∼1 month of age. The animals were divided into two cohorts: (i) a long-term group, which was followed to humane end point; and (ii) a short-term group, which was analysed 16 weeks post-treatment. Clinical assessments included neurological exams, CSF and urine biomarkers, and 7 T MRI and magentic resonance spectroscopy (MRS). Post-mortem analysis included ß-galactosidase and virus distribution, histological analysis and ganglioside content. Untreated GM1 animals survived 8.0 ± 0.6 months while intravenous treatment increased survival to an average of 3.5 years (n = 2) with substantial improvements in quality of life and neurological function. Neurological abnormalities, which in untreated animals progress to the inability to stand and debilitating neurological disease by 8 months of age, were mild in all treated animals. CSF biomarkers were normalized, indicating decreased CNS cell damage in the treated animals. Urinary glycosaminoglycans decreased to normal levels in the long-term cohort. MRI and MRS showed partial preservation of the brain in treated animals, which was supported by post-mortem histological evaluation. ß-Galactosidase activity was increased throughout the CNS, reaching carrier levels in much of the cerebrum and normal levels in the cerebellum, spinal cord and CSF. Ganglioside accumulation was significantly reduced by treatment. Peripheral tissues such as heart, skeletal muscle, and sciatic nerve also had normal ß-galactosidase activity in treated GM1 cats. GM1 histopathology was largely corrected with treatment. There was no evidence of tumorigenesis or toxicity. Restoration of ß-galactosidase activity in the CNS and peripheral organs by intravenous gene therapy led to profound increases in lifespan and quality of life in GM1 cats. These data support the promise of intravenous gene therapy as a safe, effective treatment for GM1 gangliosidosis.


Subject(s)
Gangliosidosis, GM1 , Neurodegenerative Diseases , Animals , Biomarkers , Cats , Dependovirus/genetics , G(M1) Ganglioside/therapeutic use , Gangliosides , Gangliosidosis, GM1/genetics , Gangliosidosis, GM1/pathology , Gangliosidosis, GM1/therapy , Genetic Therapy/methods , Humans , Quality of Life , Tissue Distribution , beta-Galactosidase/genetics , beta-Galactosidase/metabolism
12.
Mol Ther Methods Clin Dev ; 23: 128-134, 2021 Dec 10.
Article in English | MEDLINE | ID: mdl-34703836

ABSTRACT

Transformative results of adeno-associated virus (AAV) gene therapy in patients with spinal muscular atrophy and Leber's congenital amaurosis led to approval of the first two AAV products in the United States to treat these diseases. These extraordinary results led to a dramatic increase in the number and type of AAV gene-therapy programs. However, the field lacks non-invasive means to assess levels and duration of therapeutic protein function in patients. Here, we describe a new magnetic resonance imaging (MRI) technology for real-time reporting of gene-therapy products in the living animal in the form of an MRI probe that is activated in the presence of therapeutic protein expression. For the first time, we show reliable tracking of enzyme expression after a now in-human clinical trial AAV gene therapy (ClinicalTrials.gov: NTC03952637) encoding lysosomal acid beta-galactosidase (ßgal) using a self-immolative ßgal-responsive MRI probe. MRI enhancement in AAV-treated enzyme-deficient mice (GLB-1-/-) correlates with ßgal activity in central nervous system and peripheral organs after intracranial or intravenous AAV gene therapy, respectively. With >1,800 gene therapies in phase I/II clinical trials (ClinicalTrials.gov), development of a non-invasive method to track gene expression over time in patients is crucial to the future of the gene-therapy field.

14.
Mol Ther ; 28(10): 2150-2160, 2020 10 07.
Article in English | MEDLINE | ID: mdl-32592687

ABSTRACT

The GM2 gangliosidoses, Tay-Sachs disease (TSD) and Sandhoff disease (SD), are fatal lysosomal storage disorders caused by mutations in the HEXA and HEXB genes, respectively. These mutations cause dysfunction of the lysosomal enzyme ß-N-acetylhexosaminidase A (HexA) and accumulation of GM2 ganglioside (GM2) with ensuing neurodegeneration, and death by 5 years of age. Until recently, the most successful therapy was achieved by intracranial co-delivery of monocistronic adeno-associated viral (AAV) vectors encoding Hex alpha and beta-subunits in animal models of SD. The blood-brain barrier crossing properties of AAV9 enables systemic gene therapy; however, the requirement of co-delivery of two monocistronic AAV vectors to overexpress the heterodimeric HexA protein has prevented the use of this approach. To address this need, we developed multiple AAV constructs encoding simultaneously HEXA and HEXB using AAV9 and AAV-PHP.B and tested their therapeutic efficacy in 4- to 6-week-old SD mice after systemic administration. Survival and biochemical outcomes revealed superiority of the AAV vector design using a bidirectional CBA promoter with equivalent dose-dependent outcomes for both capsids. AAV-treated mice performed normally in tests of motor function, CNS GM2 ganglioside levels were significantly reduced, and survival increased by >4-fold with some animals surviving past 2 years of age.


Subject(s)
Dependovirus/genetics , Genetic Therapy , Genetic Vectors/genetics , Sandhoff Disease/therapy , Animals , Disease Management , Disease Models, Animal , G(M2) Ganglioside/metabolism , Gene Expression , Genetic Predisposition to Disease , Genetic Therapy/methods , Genetic Vectors/administration & dosage , Mice , Mutation , Sandhoff Disease/genetics , Tay-Sachs Disease/genetics , Tay-Sachs Disease/metabolism , Tay-Sachs Disease/therapy , Transgenes , beta-N-Acetylhexosaminidases/genetics , beta-N-Acetylhexosaminidases/metabolism
15.
Hum Gene Ther ; 31(1-2): 90-102, 2020 01.
Article in English | MEDLINE | ID: mdl-31696742

ABSTRACT

Adeno-associated virus (AAV) gene therapy for neurological diseases was revolutionized by the discovery that AAV9 crosses the blood-brain barrier (BBB) after systemic administration. Transformative results have been documented in various inherited diseases, but overall neuronal transduction efficiency is relatively low. The recent development of AAV-PHP.B with ∼60-fold higher efficiency than AAV9 in transducing the adult mouse brain was the major first step toward acquiring the ability to deliver genes to the majority of cells in the central nervous system (CNS). However, little is known about the mechanism utilized by AAV to cross the BBB, and how it may diverge across species. In this study, we show that AAV-PHP.B is ineffective for systemic CNS gene transfer in the inbred strains BALB/cJ, BALB/cByJ, A/J, NOD/ShiLtJ, NZO/HILtJ, C3H/HeJ, and CBA/J mice, but it is highly potent in C57BL/6J, FVB/NJ, DBA/2J, 129S1/SvImJ, and AKR/J mice and also the outbred strain CD-1. We used the power of classical genetics to uncover the molecular mechanisms AAV-PHP.B engages to transduce CNS at high efficiency, and by quantitative trait locus mapping we identify a 6 Mb region in chromosome 15 with an logarithm of the odds (LOD) score ∼20, including single nucleotide polymorphisms in the coding region of 9 different genes. Comparison of the publicly available data on the genome sequence of 16 different mouse strains, combined with RNA-seq data analysis of brain microcapillary endothelia, led us to conclude that the expression level of Ly6a is likely the determining factor for differential efficacy of AAV-PHP.B in transducing the CNS across different mouse strains.


Subject(s)
Antigens, Ly/genetics , Blood-Brain Barrier/metabolism , Central Nervous System/metabolism , Dependovirus/genetics , Gene Expression , Genetic Vectors/genetics , Membrane Proteins/genetics , Transduction, Genetic , Animals , Antigens, Ly/metabolism , Endothelium, Vascular/metabolism , Female , Gene Transfer Techniques , Genes, Reporter , Genetic Vectors/administration & dosage , Genetic Vectors/pharmacokinetics , Genotype , Male , Membrane Proteins/metabolism , Mice , Mice, Transgenic , Quantitative Trait Loci , Species Specificity
16.
Mol Ther ; 28(2): 411-421, 2020 02 05.
Article in English | MEDLINE | ID: mdl-31813800

ABSTRACT

Global gene delivery to the CNS has therapeutic importance for the treatment of neurological disorders that affect the entire CNS. Due to direct contact with the CNS, cerebrospinal fluid (CSF) is an attractive route for CNS gene delivery. A safe and effective route to achieve global gene distribution in the CNS is needed, and administration of genes through the cisterna magna (CM) via a suboccipital puncture results in broad distribution in the brain and spinal cord. However, translation of this technique to clinical practice is challenging due to the risk of serious and potentially fatal complications in patients. Herein, we report development of a gene therapy delivery method to the CM through adaptation of an intravascular microcatheter, which can be safely navigated intrathecally under fluoroscopic guidance. We examined the safety, reproducibility, and distribution/transduction of this method in sheep using a self-complementary adeno-associated virus 9 (scAAV9)-GFP vector. This technique was used to treat two Tay-Sachs disease patients (30 months old and 7 months old) with AAV gene therapy. No adverse effects were observed during infusion or post-treatment. This delivery technique is a safe and minimally invasive alternative to direct infusion into the CM, achieving broad distribution of AAV gene transfer to the CNS.


Subject(s)
Cisterna Magna/metabolism , Dependovirus/genetics , Gene Expression , Gene Transfer Techniques , Genetic Vectors/genetics , Transduction, Genetic , Animals , Catheters , Central Nervous System/metabolism , Genes, Reporter , Genetic Therapy , Genetic Vectors/administration & dosage , Humans , Injections, Spinal , Magnetic Resonance Imaging , Models, Animal , Sheep , Surgery, Computer-Assisted , Tomography, X-Ray Computed , Transgenes , Video Recording
17.
Viseu; s.n; 20140000. 107 p. ilust, tabelas.
Thesis in Portuguese | BDENF - Nursing | ID: biblio-1253953

ABSTRACT

Introdução ­ A adesão aos programas de reabilitação constitui uma fonte de preocupação transversal a todos os profissionais de saúde. Com o evoluir dos tempos o utente deixou de ter um papel passivo relativamente às prescrições médicas e passou a ter uma responsabilização individual pelo seu estado de saúde e controlo da sua doença. Porém, a taxa de incumprimentos continua ainda particularmente elevada.Nestaperspectiva, o objectivo central deste estudo é determinar a influência dos determinantes sociodemográficos e de contexto laboral na perceção dos profissionais de saúde face à adesão dos utentes aos programas de reabilitação. Métodos ­ Trata-se de uma pesquisa do tipo quantitativa, transversal, descritivo correlacional, recorrendo a uma amostra não probabilística constituída por 98 profissionais de saúde, com idades compreendidas entre os 22 anos e os 58 anos ( ̅ = 39,80; Dp= 9,96) e maioritariamente do sexo feminino (58,16%). O instrumento de colheita de dados incorporou uma ficha de caraterização sóciodemográfica e profissional, e uma escala de medida validada e aferida para a mensuração da perceção da adesão. Resultados ­ O score da perceção dos profissionais de saúde face à adesão dos utentes aos programas de reabilitação é de 6,48, sendo considerado um valor acima da média. São tendencialmente os profissionais de saúde, do sexo feminino, a apresentar maior perceção face à adesão dos utentes aos programas de reabilitação. Outras variáveis revelam, igualmente,um efeito estatisticamente significativosobre a perceção dos profissionais de saúde face à adesão dos utentes, concretamente: são os enfermeiros especialistascomparativamente aosmédicos que apresentam melhor score no que toca às estratégias usadas por estes profissionais;no que respeita aos métodos da adesãosão os profissionais que trabalham com utentes com patologia cárdio-respiratóriaque apresentam melhor score em relação aos profissionais de saúde que trabalham com utentes com patologia orto-traumatológica e reumatológica, e são também os profissionais que trabalham com utentes com patologia neurológica a apresentar melhor score comparativamente aos profissionais que trabalham com utentes com patologia ortotraumatológica e reumatológica. Conclusão ­As evidências encontradas, salientam que existem muitas dúvidas dos profissionais de saúde acerca da problemática da adesão, e permitem inferir que enquanto profissionais de saúde temos de continuar a desenvolver estratégias,com envolvimento directodo utente, por forma a diminuir a não adesão destes aos programas de reabilitação. Propomos a formação contínua dos profissionais bem como a realização de campanhas de sensibilização junto da comunidade. Também uma reflexão sobre a abrangência dos conteúdosprogramáticosescolares poderá vir a dar contributos pertinentes para a solução desta problemática.


Introduction ­ Sticking with a rehabilitation program is still a source of concern to all healthcare professionals. Patients have no longer a passive role towards medical prescriptions and have now an individual responsibility in their own health and control of the disease. However, the default rates associated with these programs are still very high. So, regarding this subject, the main goal of this study was to determine the influence of socialdemographic and labor factors in healthcare professionals perception towards patient adhesion to rehabilitation treatments. Methods ­ This was a cross-sectional and descriptive study in witch a questionnaire was submitted to 98 healthcare professionals, mostly female, with ages between 22 and 58 years old. They answered questions about socio-demographic profiles in order to measure the scale of patient adhesion to rehabilitation programs. Results ­ The score of healthcare professionals towards patient adhesion to rehabilitation programs is 6.48, a value above average. This study shows that are mostly female healthcare professionals who present the higher perception towards patient adhesion. Study results also reveal that strategies used by specialist nurses are more likely to prove patient adhesion than those used by doctors. When it comes to the methods used to promote patient adhesion there is a higher score in cardio-respiratory pathology when compared to the ones used in trauma and rheumatology. Healthcare professionals who work with neurology patients have a higher score than the ones who work with trauma and cardio-respiratory patients. Conclusions ­ Study results suggest that there is still a long way to go when it comes to finding strategies to improve patient adhesion to rehabilitation programs. To contribute for the professional development in this field, services must provide both continuous training and formation to the healthcare professionals as well as promote public awareness campaigns to encourage patients to keep up with their rehabilitation programs. Study findings also suggest that academic contents should be reviewed in order to help healthcare professionals to be prepared to encourage their patients while in treatment. K


Subject(s)
Perception , Rehabilitation , Patient Compliance , Health Personnel , Health Promotion
18.
Biochim Biophys Acta ; 1832(8): 1183-93, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23579071

ABSTRACT

Transthyretin (TTR) is a plasma and cerebrospinal fluid (CSF)-circulating homotetrameric protein. More than 100 point mutations have been identified in the TTR gene and several are related with amyloid diseases. Here we focused our attention in the TTR L12P variant associated with severe peripheral neuropathy and leptomeningeal amyloidosis. By using different cell lines derived from tissues specialized on TTR synthesis, such as the hepatocyte and the choroid plexus expressing WT, V30M, or L12P TTR variants we analyzed secretion, intracellular aggregation and degradation patterns. Also, we used liver-specific AAV gene transfer to assess expression of the L12P variant in vivo. We found the following: (i) decreased secretion with intracellular aggregation of TTR L12P in hepatoma cells relative to WT and V30M variant; this differential property of TTR L12P variant was also observed in mice injected with L12P AAV vector; (ii) differential N-glycosylation pattern of L12P variant in hepatoma cell lysates, conditioned media and mouse sera, which might represent an escape mechanism from ERAD degradation; (iii) intracellular L12P TTR aggregates mainly localized to lysosomes in cultured cells and liver; and (iv) none of the above findings were present in choroid plexus derived cells, suggesting particular secretion/quality control mechanisms that might contribute to leptomeningeal amyloidosis associated with the L12P variant. These observations open new avenues for the treatment of TTR associated leptomeningeal amyloidosis.


Subject(s)
Liver/physiology , Lysosomes/physiology , Prealbumin/biosynthesis , Amyloid Neuropathies, Familial/genetics , Amyloid Neuropathies, Familial/metabolism , Amyloid Neuropathies, Familial/pathology , Amyloidosis/genetics , Amyloidosis/metabolism , Amyloidosis/pathology , Animals , Autophagy/genetics , Autophagy/physiology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line , Cell Line, Tumor , Choroid Plexus/metabolism , Choroid Plexus/pathology , Glycosylation , HEK293 Cells , Hepatocytes/metabolism , Hepatocytes/physiology , Humans , Liver/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Lysosomes/genetics , Lysosomes/metabolism , Mice , Mice, Transgenic , Prealbumin/genetics , Prealbumin/metabolism
19.
Pharmacol Res ; 62(6): 514-22, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20692343

ABSTRACT

Carvedilol is a ß-antagonist with strong anti-oxidant effect in lipids, proteins and superoxide production protecting biological membranes from oxidative stress. We hypothesised a possible therapeutical application of carvedilol in familial amyloidotic polyneuropathy (FAP), a neurodegenerative disease caused by deposition of transthyretin (TTR) amyloid fibrils. Oxidative stress, apoptosis and inflammation related to aggregation of non-fibrillar and fibrillar TTR have been detected both in pre-symptomatic and symptomatic stages of the disease, respectively. In this study we show by semi-quantitative immunohistochemistry and western blot analysis that administration of carvedilol to a transgenic mouse model of FAP influences the expression of oxidative and apoptotic biomarkers usually associated with TTR deposition, namely oxidation products such as HNE and 8-OHdG, and markers of ER stress. Most important, carvedilol treatment significantly reduced TTR aggregates in as much as 50%. We also observed that carvedilol rescues a mice neuroblastoma cell line from death induced by TTR oligomers, by decreasing activation of BiP and other ER stress biomarkers. Since carvedilol has no effect on TTR aggregation "in vitro", this finding points for the "in vivo" modulation of TTR aggregation by oxidative stress and apoptosis and prompts for the use of this safe drug in prophylactic and therapeutical measures in the FAP population.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Amyloid Neuropathies, Familial/drug therapy , Antioxidants/therapeutic use , Carbazoles/therapeutic use , Polyneuropathies/drug therapy , Prealbumin/metabolism , Propanolamines/therapeutic use , Amyloid Neuropathies, Familial/pathology , Animals , Apoptosis/drug effects , Carvedilol , Humans , Mice , Mice, Transgenic , Oxidation-Reduction/drug effects , Oxidative Stress/drug effects , Polyneuropathies/pathology , Prealbumin/analysis , Protein Multimerization/drug effects
20.
Biochim Biophys Acta ; 1782(9): 517-22, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18572024

ABSTRACT

Tauroursodeoxycholic acid (TUDCA) is a unique natural compound that acts as a potent anti-apoptotic and anti-oxidant agent, reducing cytotoxicity in several neurodegenerative diseases. Since oxidative stress, apoptosis and inflammation are associated with transthyretin (TTR) deposition in Familial Amyloidotic Polyneuropathy (FAP), we investigated the possible TUDCA therapeutical application in this disease. We show by semi-quantitative immunohistochemistry and western blotting that administration of TUDCA to a transgenic mouse model of FAP decreased apoptotic and oxidative biomarkers usually associated with TTR deposition, namely the ER stress markers BiP and eIF2alpha, the Fas death receptor and oxidation products such as 3-nitrotyrosine. Most important, TUDCA treatment significantly reduced TTR toxic aggregates in as much as 75%. Since TUDCA has no effect on TTR aggregation "in vitro", this finding points for the "in vivo" modulation of TTR aggregation by cellular responses, such as by oxidative stress, ER stress and apoptosis and prompts for the use of this safe drug in prophylactic and therapeutic measures in FAP.


Subject(s)
Amyloid Neuropathies, Familial/metabolism , Apoptosis/drug effects , Prealbumin/metabolism , Taurochenodeoxycholic Acid/pharmacology , Animals , Disease Models, Animal , Endoplasmic Reticulum/drug effects , Endoplasmic Reticulum/pathology , Endoplasmic Reticulum Chaperone BiP , Gastrointestinal Tract/drug effects , Gastrointestinal Tract/metabolism , Heat-Shock Proteins/metabolism , Humans , Immunohistochemistry , Methionine/genetics , Mice , Mice, Transgenic , Molecular Chaperones/metabolism , Mutant Proteins/metabolism , Mutation/genetics , Oxidation-Reduction/drug effects , Prealbumin/chemistry , Prealbumin/ultrastructure , Protein Structure, Quaternary , Thermodynamics , Tyrosine/analogs & derivatives , Tyrosine/metabolism , fas Receptor/metabolism
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