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1.
Mol Cell ; 83(18): 3314-3332.e9, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37625404

RESUMEN

Hsp104 is an AAA+ protein disaggregase that solubilizes and reactivates proteins trapped in aggregated states. We have engineered potentiated Hsp104 variants to mitigate toxic misfolding of α-synuclein, TDP-43, and FUS implicated in fatal neurodegenerative disorders. Though potent disaggregases, these enhanced Hsp104 variants lack substrate specificity and can have unfavorable off-target effects. Here, to lessen off-target effects, we engineer substrate-specific Hsp104 variants. By altering Hsp104 pore loops that engage substrate, we disambiguate Hsp104 variants that selectively suppress α-synuclein toxicity but not TDP-43 or FUS toxicity. Remarkably, α-synuclein-specific Hsp104 variants emerge that mitigate α-synuclein toxicity via distinct ATPase-dependent mechanisms involving α-synuclein disaggregation or detoxification of soluble α-synuclein conformers. Importantly, both types of α-synuclein-specific Hsp104 variant reduce dopaminergic neurodegeneration in a C. elegans model of Parkinson's disease more effectively than non-specific variants. We suggest that increasing the substrate specificity of enhanced disaggregases could be applied broadly to tailor therapeutics for neurodegenerative disease.


Asunto(s)
Enfermedades Neurodegenerativas , Proteínas de Saccharomyces cerevisiae , Animales , Humanos , alfa-Sinucleína/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo
2.
iScience ; 26(6): 106859, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37260751

RESUMEN

Failure of inherently protective cellular processes and misfolded protein-associated stress contribute to the progressive loss of dopamine (DA) neurons characteristic of Parkinson's disease (PD). A disease-modifying role for the microbiome has recently emerged in PD, representing an impetus to employ the soil-dwelling nematode, Caenorhabditis elegans, as a preclinical model to correlate changes in gene expression with neurodegeneration in transgenic animals grown on distinct bacterial food sources. Even under tightly controlled conditions, hundreds of differentially expressed genes and a robust neuroprotective response were discerned between clonal C. elegans strains overexpressing human alpha-synuclein in the DA neurons fed either one of only two subspecies of Escherichia coli. Moreover, this neuroprotection persisted in a transgenerational manner. Genetic analysis revealed a requirement for the double-stranded RNA (dsRNA)-mediated gene silencing machinery in conferring neuroprotection. In delineating the contribution of individual genes, evidence emerged for endopeptidase activity and heme-associated pathway(s) as mechanistic components for modulating dopaminergic neuroprotection.

3.
Cells ; 12(8)2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-37190079

RESUMEN

Oxidative stress is a contributing factor to Parkinson's disease (PD). Considering the prevalence of sporadic PD, environmental exposures are postulated to increase reactive oxygen species and either incite or exacerbate neurodegeneration. We previously determined that exposure to the common soil bacterium, Streptomyces venezuelae (S. ven), enhanced oxidative stress and mitochondrial dysfunction in Caenorhabditis elegans, leading to dopaminergic (DA) neurodegeneration. Here, S. ven metabolite exposure in C. elegans was followed by RNA-Seq analysis. Half of the differentially identified genes (DEGs) were associated with the transcription factor DAF-16 (FOXO), which is a key node in regulating stress response. Our DEGs were enriched for Phase I (CYP) and Phase II (UGT) detoxification genes and non-CYP Phase I enzymes associated with oxidative metabolism, including the downregulated xanthine dehydrogenase gene, xdh-1. The XDH-1 enzyme exhibits reversible interconversion to xanthine oxidase (XO) in response to calcium. S. ven metabolite exposure enhanced XO activity in C. elegans. The chelation of calcium diminishes the conversion of XDH-1 to XO and results in neuroprotection from S. ven exposure, whereas CaCl2 supplementation enhanced neurodegeneration. These results suggest a defense mechanism that delimits the pool of XDH-1 available for interconversion to XO, and associated ROS production, in response to metabolite exposure.


Asunto(s)
Caenorhabditis elegans , Xantina Deshidrogenasa , Animales , Xantina Deshidrogenasa/metabolismo , Caenorhabditis elegans/metabolismo , Calcio/metabolismo , Xantina Oxidasa/metabolismo , Especies Reactivas de Oxígeno/metabolismo
4.
J Dev Biol ; 11(2)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37218814

RESUMEN

Differential RNA editing by adenosine deaminases that act on RNA (ADARs) has been implicated in several neurological disorders, including Parkinson's disease (PD). Here, we report results of a RNAi screen of genes differentially regulated in adr-2 mutants, normally encoding the only catalytically active ADAR in Caenorhabditis elegans, ADR-2. Subsequent analysis of candidate genes that alter the misfolding of human α-synuclein (α-syn) and dopaminergic neurodegeneration, two PD pathologies, reveal that reduced expression of xdh-1, the ortholog of human xanthine dehydrogenase (XDH), is protective against α-synuclein-induced dopaminergic neurodegeneration. Further, RNAi experiments show that WHT-2, the worm ortholog of the human ABCG2 transporter and a predicted interactor of XDH-1, is the rate-limiting factor in the ADR-2, XDH-1, WHT-2 system for dopaminergic neuroprotection. In silico structural modeling of WHT-2 indicates that the editing of one nucleotide in the wht-2 mRNA leads to the substitution of threonine with alanine at residue 124 in the WHT-2 protein, changing hydrogen bonds in this region. Thus, we propose a model where wht-2 is edited by ADR-2, which promotes optimal export of uric acid, a known substrate of WHT-2 and a product of XDH-1 activity. In the absence of editing, uric acid export is limited, provoking a reduction in xdh-1 transcription to limit uric acid production and maintain cellular homeostasis. As a result, elevation of uric acid is protective against dopaminergic neuronal cell death. In turn, increased levels of uric acid are associated with a decrease in ROS production. Further, downregulation of xdh-1 is protective against PD pathologies because decreased levels of XDH-1 correlate to a concomitant reduction in xanthine oxidase (XO), the form of the protein whose by-product is superoxide anion. These data indicate that modifying specific targets of RNA editing may represent a promising therapeutic strategy for PD.

5.
MicroPubl Biol ; 20232023.
Artículo en Inglés | MEDLINE | ID: mdl-37033702

RESUMEN

Previous research has described promising neuroprotective and/or antioxidant properties for extracts derived from a few Salvia (sage) species. Here, six new Salvia species were isolated during flowering times from plants native to Turkey. Extracts were prepared and then examined for their potential to rescue both anterior and posterior mechanosensory behavioral defects in a transgenic C. elegans Alzheimer's disease model that expresses human amyloid-beta (Aß) peptide (1-42) exclusively in the glutamatergic neurons. Extracts from all six Salvia species rescued anterior touch response defects while only three rescued posterior touch response defects, compared to the Aß controls.

6.
Proc Natl Acad Sci U S A ; 120(7): e2210712120, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36745808

RESUMEN

Whole-exome sequencing of Parkinson's disease (PD) patient DNA identified single-nucleotide polymorphisms (SNPs) in the tyrosine nonreceptor kinase-2 (TNK2) gene. Although this kinase had a previously demonstrated activity in preventing the endocytosis of the dopamine reuptake transporter (DAT), a causal role for TNK2-associated dysfunction in PD remains unresolved. We postulated the dopaminergic neurodegeneration resulting from patient-associated variants in TNK2 were a consequence of aberrant or prolonged TNK2 overactivity, the latter being a failure in TNK2 degradation by an E3 ubiquitin ligase, neuronal precursor cell-expressed developmentally down-regulated-4 (NEDD4). Interestingly, systemic RNA interference protein-3 (SID-3) is the sole TNK2 ortholog in the nematode Caenorhabditis elegans, where it is an established effector of epigenetic gene silencing mediated through the dsRNA-transporter, SID-1. We hypothesized that TNK2/SID-3 represents a node of integrated dopaminergic and epigenetic signaling essential to neuronal homeostasis. Use of a TNK2 inhibitor (AIM-100) or a NEDD4 activator [N-aryl benzimidazole 2 (NAB2)] in bioassays for either dopamine- or dsRNA-uptake into worm dopaminergic neurons revealed that sid-3 mutants displayed robust neuroprotection from 6-hydroxydopamine (6-OHDA) exposures, as did AIM-100 or NAB2-treated wild-type animals. Furthermore, NEDD4 activation by NAB2 in rat primary neurons correlated to a reduction in TNK2 levels and the attenuation of 6-OHDA neurotoxicity. CRISPR-edited nematodes engineered to endogenously express SID-3 variants analogous to TNK2 PD-associated SNPs exhibited enhanced susceptibility to dopaminergic neurodegeneration and circumvented the RNAi resistance characteristic of SID-3 dysfunction. This research exemplifies a molecular etiology for PD whereby dopaminergic and epigenetic signaling are coordinately regulated to confer susceptibility or resilience to neurodegeneration.


Asunto(s)
Enfermedad de Parkinson , Animales , Ratas , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Dopamina/metabolismo , Oxidopamina , Neuroprotección/genética , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Neuronas Dopaminérgicas/metabolismo , Epigénesis Genética , Modelos Animales de Enfermedad
7.
PLoS Genet ; 18(8): e1010115, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35984862

RESUMEN

The fine-tuning of gene expression is critical for all cellular processes; aberrations in this activity can lead to pathology, and conversely, resilience. As their role in coordinating organismal responses to both internal and external factors have increasingly come into focus, small non-coding RNAs have emerged as an essential component to disease etiology. Using Systemic RNA interference Defective (SID) mutants of the nematode Caenorhabditis elegans, deficient in gene silencing, we examined the potential consequences of dysfunctional epigenomic regulation in the context of Parkinson's disease (PD). Specifically, the loss of either the sid-1 or sid-3 genes, which encode a dsRNA transporter and an endocytic regulatory non-receptor tyrosine kinase, respectively, conferred neuroprotection to dopaminergic (DA) neurons in an established transgenic C. elegans strain wherein overexpression of human α-synuclein (α-syn) from a chromosomally integrated multicopy transgene causes neurodegeneration. We further show that knockout of a specific microRNA, mir-2, attenuates α-syn neurotoxicity; suggesting that the native targets of mir-2-dependent gene silencing represent putative neuroprotective modulators. In support of this, we demonstrated that RNAi knockdown of multiple mir-2 targets enhanced α-syn-induced DA neurodegeneration. Moreover, we demonstrate that mir-2 overexpression originating in the intestine can induce neurodegeneration of DA neurons, an effect that was reversed by pharmacological inhibition of SID-3 activity. Interestingly, sid-1 mutants retained mir-2-induced enhancement of neurodegeneration. Transcriptomic analysis of α-syn animals with and without a sid-1 mutation revealed 27 differentially expressed genes with human orthologs related to a variety of diseases, including PD. Among these was pgp-8, encoding a P-glycoprotein-related ABC transporter. Notably, sid-1; pgp-8 double mutants abolished the neurodegeneration resulting from intestinal mir-2 overexpression. This research positions known regulators of small RNA-dependent gene silencing within a framework that facilitates mechanistic evaluation of epigenetic responses to exogenous and endogenous factors influencing DA neurodegeneration, revealing a path toward new targets for therapeutic intervention of PD.


Asunto(s)
Proteínas de Caenorhabditis elegans , Enfermedad de Parkinson , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Humanos , Enfermedad de Parkinson/patología , Interferencia de ARN , ARN Bicatenario/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
8.
Hum Mol Genet ; 31(R1): R37-R46, 2022 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-35994032

RESUMEN

The exponential accumulation of DNA sequencing data has opened new avenues for discovering the causative roles of single-nucleotide polymorphisms (SNPs) in neurological diseases. The opportunities emerging from this are staggering, yet only as good as our abilities to glean insights from this surplus of information. Whereas computational biology continues to improve with respect to predictions and molecular modeling, the differences between in silico and in vivo analysis remain substantial. Invertebrate in vivo model systems represent technically advanced, experimentally mature, high-throughput, efficient and cost-effective resources for investigating a disease. With a decades-long track record of enabling investigators to discern function from DNA, fly (Drosophila) and worm (Caenorhabditis elegans) models have never been better poised to serve as living engines of discovery. Both of these animals have already proven useful in the classification of genetic variants as either pathogenic or benign across a range of neurodevelopmental and neurodegenerative disorders-including autism spectrum disorders, ciliopathies, amyotrophic lateral sclerosis, Alzheimer's and Parkinson's disease. Pathogenic SNPs typically display distinctive phenotypes in functional assays when compared with null alleles and frequently lead to protein products with gain-of-function or partial loss-of-function properties that contribute to neurological disease pathogenesis. The utility of invertebrates is logically limited by overt differences in anatomical and physiological characteristics, and also the evolutionary distance in genome structure. Nevertheless, functional annotation of disease-SNPs using invertebrate models can expedite the process of assigning cellular and organismal consequences to mutations, ascertain insights into mechanisms of action, and accelerate therapeutic target discovery and drug development for neurological conditions.


Asunto(s)
Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Animales , Humanos , Caenorhabditis elegans/genética , Drosophila/genética , Mutación , Enfermedades Neurodegenerativas/genética , Enfermedad de Parkinson/genética , Modelos Animales de Enfermedad , Polimorfismo de Nucleótido Simple
9.
NPJ Parkinsons Dis ; 8(1): 74, 2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35680956

RESUMEN

Synucleinopathy (Parkinson's disease (PD); Lewy body dementia) disease-modifying treatments represent a huge unmet medical need. Although the PD-causing protein α-synuclein (αS) interacts with lipids and fatty acids (FA) physiologically and pathologically, targeting FA homeostasis for therapeutics is in its infancy. We identified the PD-relevant target stearoyl-coA desaturase: inhibiting monounsaturated FA synthesis reversed PD phenotypes. However, lipid degradation also generates FA pools. Here, we identify the rate-limiting lipase enzyme, LIPE, as a candidate target. Decreasing LIPE in human neural cells reduced αS inclusions. Patient αS triplication vs. corrected neurons had increased pSer129 and insoluble αS and decreased αS tetramer:monomer ratios. LIPE inhibition rescued all these and the abnormal unfolded protein response. LIPE inhibitors decreased pSer129 and restored tetramer:monomer equilibrium in αS E46K-expressing human neurons. LIPE reduction in vivo alleviated αS-induced dopaminergic neurodegeneration in Caenorhabditis elegans. Co-regulating FA synthesis and degradation proved additive in rescuing PD phenotypes, signifying co-targeting as a therapeutic strategy.

10.
Nat Biomed Eng ; 6(1): 76-93, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34992270

RESUMEN

A reduced removal of dysfunctional mitochondria is common to aging and age-related neurodegenerative pathologies such as Alzheimer's disease (AD). Strategies for treating such impaired mitophagy would benefit from the identification of mitophagy modulators. Here we report the combined use of unsupervised machine learning (involving vector representations of molecular structures, pharmacophore fingerprinting and conformer fingerprinting) and a cross-species approach for the screening and experimental validation of new mitophagy-inducing compounds. From a library of naturally occurring compounds, the workflow allowed us to identify 18 small molecules, and among them two potent mitophagy inducers (Kaempferol and Rhapontigenin). In nematode and rodent models of AD, we show that both mitophagy inducers increased the survival and functionality of glutamatergic and cholinergic neurons, abrogated amyloid-ß and tau pathologies, and improved the animals' memory. Our findings suggest the existence of a conserved mechanism of memory loss across the AD models, this mechanism being mediated by defective mitophagy. The computational-experimental screening and validation workflow might help uncover potent mitophagy modulators that stimulate neuronal health and brain homeostasis.


Asunto(s)
Enfermedad de Alzheimer , Mitofagia , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides , Animales , Aprendizaje Automático , Mitofagia/fisiología , Flujo de Trabajo
11.
Biology (Basel) ; 10(8)2021 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-34440004

RESUMEN

B-cell lymphoma-extra large (Bcl-xL) is a mitochondrial protein known to inhibit mitochondria-dependent intrinsic apoptotic pathways. An increasing number of studies have demonstrated that Bcl-xL is critical in regulating neuronal energy metabolism and has a protective role in pathologies associated with an energy deficit. However, it is less known how Bcl-xL regulates physiological processes of the brain. In this study, we hypothesize that Bcl-xL is required for neurite branching and maturation during neuronal development by improving local energy metabolism. We found that the absence of Bcl-xL in rat primary hippocampal neurons resulted in mitochondrial dysfunction. Specifically, the ATP/ADP ratio was significantly decreased in the neurites of Bcl-xL depleted neurons. We further found that neurons transduced with Bcl-xL shRNA or neurons treated with ABT-263, a pharmacological inhibitor of Bcl-xL, showed impaired mitochondrial motility. Neurons lacking Bcl-xL had significantly decreased anterograde and retrograde movement of mitochondria and an increased stationary mitochondrial population when Bcl-xL was depleted by either means. These mitochondrial defects, including loss of ATP, impaired normal neurite development. Neurons lacking Bcl-xL showed significantly decreased neurite arborization, growth and complexity. Bcl-xL depleted neurons also showed impaired synapse formation. These neurons showed increased intracellular calcium concentration and were more susceptible to excitotoxic challenge. Bcl-xL may support positioning of mitochondria at metabolically demanding regions of neurites like branching points. Our findings suggest a role for Bcl-xL in physiological regulation of neuronal growth and development.

12.
EMBO Mol Med ; 13(5): e13258, 2021 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-33851776

RESUMEN

Vacuolar protein sorting 41 (VPS41) is as part of the Homotypic fusion and Protein Sorting (HOPS) complex required for lysosomal fusion events and, independent of HOPS, for regulated secretion. Here, we report three patients with compound heterozygous mutations in VPS41 (VPS41S285P and VPS41R662* ; VPS41c.1423-2A>G and VPS41R662* ) displaying neurodegeneration with ataxia and dystonia. Cellular consequences were investigated in patient fibroblasts and VPS41-depleted HeLa cells. All mutants prevented formation of a functional HOPS complex, causing delayed lysosomal delivery of endocytic and autophagic cargo. By contrast, VPS41S285P enabled regulated secretion. Strikingly, loss of VPS41 function caused a cytosolic redistribution of mTORC1, continuous nuclear localization of Transcription Factor E3 (TFE3), enhanced levels of LC3II, and a reduced autophagic response to nutrient starvation. Phosphorylation of mTORC1 substrates S6K1 and 4EBP1 was not affected. In a C. elegans model of Parkinson's disease, co-expression of VPS41S285P /VPS41R662* abolished the neuroprotective function of VPS41 against α-synuclein aggregates. We conclude that the VPS41 variants specifically abrogate HOPS function, which interferes with the TFEB/TFE3 axis of mTORC1 signaling, and cause a neurodegenerative disease.


Asunto(s)
Enfermedades Neurodegenerativas , Animales , Autofagia , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Caenorhabditis elegans/genética , Células HeLa , Humanos , Lisosomas/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Enfermedades Neurodegenerativas/genética , Transporte de Proteínas , Proteínas de Transporte Vesicular/metabolismo
13.
iScience ; 24(3): 102140, 2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33665559

RESUMEN

Tobacco smoking is a risk factor for several human diseases. Conversely, smoking also reduces the prevalence of Parkinson's disease, whose hallmark is degeneration of substantia nigra dopaminergic neurons (DNs). We use C. elegans as a model to investigate whether tobacco-derived nicotine activates nicotinic acetylcholine receptors (nAChRs) to selectively protect DNs. Using this model, we demonstrate conserved functions of DN-expressed nAChRs. We find that DOP-2, a D3-receptor homolog; MCU-1, a mitochondrial calcium uniporter; PINK-1 (PTEN-induced kinase 1); and PDR-1 (Parkin) are required for nicotine-mediated protection of DNs. Together, our results support involvement of a calcium-modulated, mitochondrial stress-activated PINK1/Parkin-dependent pathway in nicotine-induced neuroprotection. This suggests that nicotine-selective protection of substantia nigra DNs is due to the confluence of two factors: first, their unique vulnerability to mitochondrial stress, which is mitigated by increased mitochondrial quality control due to PINK1 activation, and second, their specific expression of D3-receptors.

14.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33723042

RESUMEN

Ykt6 is a soluble N-ethylmaleimide sensitive factor activating protein receptor (SNARE) critically involved in diverse vesicular fusion pathways. While most SNAREs rely on transmembrane domains for their activity, Ykt6 dynamically cycles between the cytosol and membrane-bound compartments where it is active. The mechanism that regulates these transitions and allows Ykt6 to achieve specificity toward vesicular pathways is unknown. Using a Parkinson's disease (PD) model, we found that Ykt6 is phosphorylated at an evolutionarily conserved site which is regulated by Ca2+ signaling. Through a multidisciplinary approach, we show that phosphorylation triggers a conformational change that allows Ykt6 to switch from a closed cytosolic to an open membrane-bound form. In the phosphorylated open form, the spectrum of protein interactions changes, leading to defects in both the secretory and autophagy pathways, enhancing toxicity in PD models. Our studies reveal a mechanism by which Ykt6 conformation and activity are regulated with potential implications for PD.


Asunto(s)
Secuencia Conservada , Modelos Moleculares , Conformación Proteica , Proteínas R-SNARE/química , Proteínas R-SNARE/metabolismo , Aminoácidos , Autofagia , Proteínas Portadoras/química , Proteínas Portadoras/metabolismo , Membrana Celular/metabolismo , Evolución Molecular , Fosforilación , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Proteínas R-SNARE/genética , Relación Estructura-Actividad
15.
Elife ; 92020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33319748

RESUMEN

The AAA+ protein disaggregase, Hsp104, increases fitness under stress by reversing stress-induced protein aggregation. Natural Hsp104 variants might exist with enhanced, selective activity against neurodegenerative disease substrates. However, natural Hsp104 variation remains largely unexplored. Here, we screened a cross-kingdom collection of Hsp104 homologs in yeast proteotoxicity models. Prokaryotic ClpG reduced TDP-43, FUS, and α-synuclein toxicity, whereas prokaryotic ClpB and hyperactive variants were ineffective. We uncovered therapeutic genetic variation among eukaryotic Hsp104 homologs that specifically antagonized TDP-43 condensation and toxicity in yeast and TDP-43 aggregation in human cells. We also uncovered distinct eukaryotic Hsp104 homologs that selectively antagonized α-synuclein condensation and toxicity in yeast and dopaminergic neurodegeneration in C. elegans. Surprisingly, this therapeutic variation did not manifest as enhanced disaggregase activity, but rather as increased passive inhibition of aggregation of specific substrates. By exploring natural tuning of this passive Hsp104 activity, we elucidated enhanced, substrate-specific agents that counter proteotoxicity underlying neurodegeneration.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Agregación Patológica de Proteínas/patología , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , alfa-Sinucleína/metabolismo , Animales , Caenorhabditis elegans , Línea Celular , Endopeptidasa Clp/genética , Endopeptidasa Clp/metabolismo , Escherichia coli , Variación Genética/genética , Células HEK293 , Humanos , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/patología , Pliegue de Proteína , Deficiencias en la Proteostasis/genética , Deficiencias en la Proteostasis/patología , Proteína FUS de Unión a ARN/metabolismo , Saccharomyces cerevisiae
16.
J Manag Care Spec Pharm ; 26(12): 1517-1528, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33251993

RESUMEN

BACKGROUND: Multiple barriers exist for appropriate use of the proprotein convertase subtilisin/kexin type 9 enzyme inhibitors (PCSK9i) in patients with atherosclerotic cardiovascular disease (ASCVD) or familial hypercholesterolemia (FH) with inadequately controlled hypercholesterolemia despite standard therapies. Among these barriers, high payer rejection rates and inadequate prior authorization (PA) documentation by providers hinder optimal use of PCSK9i. OBJECTIVES: To (a) identify and discuss provider and payer discordances on barriers to authorization and use of PCSK9i based on clinical and real-world evidence and (b) align understanding and application of clinical, cost, safety, and efficacy data of PCSK9i. METHODS: Local groups of 3 payers and 3 providers met in 6 separate locations across the United States through a collaborative project of AMCP and PRIME Education. Responses to selected pre- and postmeeting survey questions measured changes in attitudes and beliefs regarding treatment barriers, lipid thresholds for considering PCSK9i therapy, and tactics for improving PA processes. Statistical analysis of inter- and intragroup changes in attitudes were performed by Cox proportional hazards test and Fisher's exact test for < 5 variables. RESULTS: The majority of providers and payers (67%-78%) agreed that high patient copayments and inadequate PA documentation were significant barriers to PCSK9i usage. However, payers and providers differed on beliefs that current evidence does not support PCSK9i cost-effectiveness (6% providers, 56% payers; P = 0.003) and that PA presents excessive administrative burden (72% providers, 44% payers; P = 0.09) Average increases pre- to postmeeting were noted in provider beliefs that properly documented PA forms expedite access to PCSK9i (22%-50% increase) and current authorization criteria accurately distinguish patients who benefit most from PCSK9i (6%-22%). Payers decreased in their belief that current authorization criteria accurately distinguish benefiting patients (72%-50%). Providers and payers increased in their belief that PCSK9i are cost-effective (44%-61% and 28%-50%, respectively) and were more willing to consider PCSK9i at the low-density lipoprotein cholesterol threshold of > 70 mg/dL for patients with ASCVD (78%-83% and 44%-67%, respectively) or FH (22%-39% and 22%-33%). Payers were more agreeable to less stringent PA requirements for patients with FH (33%-72%, P = 0.019) and need for standardized PA requirements (50%-83%, P = 0.034); these considerations remained high (89%) among providers after the meeting. Most participants supported educational programs for patient treatment adherence (83%) and physician/staff PA processes (83%-94%). CONCLUSIONS: Provider and payer representatives in 6 distinct geographic locations provided recommendations to improve quality of care in patients eligible for PCSK9i. Participants also provided tactical recommendations for streamlining PA documentation processes and improving awareness of PCSK9i cost-effectiveness and clinical efficacy. The majority of participants supported development of universal, standardized patient eligibility criteria and PA forms. DISCLOSURES: The study reported in this article was part of a continuing education program funded by an independent educational grant awarded by Sanofi US and Regeneron Pharmaceuticals to PRIME Education. The grantor had no role in the study design, execution, analysis, or reporting. AMCP received grant funding from PRIME to assist in the study, as well as in writing the manuscript. McCormick, Bhatt, Bays, Taub, Caldwell, Guerin, Steinhoff, and Ahmad received an honorarium from PRIME for serving as faculty for the continuing education program. McCormick, Bhatt, Bays, Taub, Caldwell, Guerin, Steinhoff, and Ahmad were involved as participants in the study. Bhatt discloses the following relationships: Advisory board: Cardax, CellProthera, Cereno Scientific, Elsevier Practice Update Cardiology, Level Ex, Medscape Cardiology, PhaseBio, PLx Pharma, Regado Biosciences; Board of directors: Boston VA Research Institute, Society of Cardiovascular Patient Care, TobeSoft; Chair: American Heart Association Quality Oversight Committee; Data monitoring committees: Baim Institute for Clinical Research (formerly Harvard Clinical Research Institute, for the PORTICO trial, funded by St. Jude Medical, now Abbott), Cleveland Clinic (including for the ExCEED trial, funded by Edwards), Contego Medical (Chair, PERFORMANCE 2), Duke Clinical Research Institute, Mayo Clinic, Mount Sinai School of Medicine (for the ENVISAGE trial, funded by Daiichi Sankyo), Population Health Research Institute; Honoraria: American College of Cardiology (Senior Associate Editor, Clinical Trials and News, ACC.org; Vice chair, ACC Accreditation Committee), Baim Institute for Clinical Research (formerly Harvard Clinical Research Institute; RE-DUAL PCI clinical trial steering committee funded by Boehringer Ingelheim; AEGIS-II executive committee funded by CSL Behring), Belvoir Publications (Editor in Chief, Harvard Heart Letter), Duke Clinical Research Institute (clinical trial steering committees, including for the PRONOUNCE trial, funded by Ferring Pharmaceuticals), HMP Global (Editor in Chief, Journal of Invasive Cardiology), Journal of the American College of Cardiology (Guest Editor; Associate Editor), K2P (Co-Chair, interdisciplinary curriculum), Level Ex, Medtelligence/ReachMD (CME steering committees), MJH Life Sciences, Population Health Research Institute (for the COMPASS operations committee, publications committee, steering committee, and USA national co-leader, funded by Bayer), Slack Publications (Chief Medical Editor, Cardiology Today's Intervention), Society of Cardiovascular Patient Care (Secretary/Treasurer), WebMD (CME steering committees); Other: Clinical Cardiology (Deputy Editor), NCDR-ACTION Registry Steering Committee (Chair), VA CART Research and Publications Committee (Chair); Research funding: Abbott, Afimmune, Amarin, Amgen, AstraZeneca, Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Cardax, Chiesi, CSL Behring, Eisai, Ethicon, Ferring Pharmaceuticals, Forest Laboratories, Fractyl, Idorsia, Ironwood, Ischemix, Lexicon, Lilly, Medtronic, Pfizer, PhaseBio, PLx Pharma, Regeneron, Roche, Sanofi Aventis, Synaptic, The Medicines Company; Royalties: Elsevier (Editor, Cardiovascular Intervention: A Companion to Braunwald's Heart Disease); Site co-investigator: Biotronik, Boston Scientific, CSI, St. Jude Medical (now Abbott), Svelte; Trustee: American College of Cardiology; Unfunded research: FlowCo, Merck, Novo Nordisk, Takeda. Bays' research site has received research grants from 89Bio, Acasti, Akcea, Allergan, Alon Medtech/Epitomee, Amarin, Amgen, AstraZeneca, Axsome, Boehringer Ingelheim, Civi, Eli Lilly, Esperion, Evidera, Gan and Lee, Home Access, Janssen, Johnson and Johnson, Lexicon, Matinas, Merck, Metavant, Novartis, Novo Nordisk, Pfizer, Regeneron, Sanofi, Selecta, TIMI, and Urovant. Bays has served as a consultant/advisor for 89Bio, Amarin, Esperion, Matinas, and Gelesis, and speaker for Esperion. McCormick, Caldwell, Guerin, Ahmad, Singh, Moreo, Carter, Heggen, and Sapir have nothing to disclose.


Asunto(s)
Anticolesterolemiantes/administración & dosificación , Enfermedades Cardiovasculares/tratamiento farmacológico , Hiperlipoproteinemia Tipo II/tratamiento farmacológico , Inhibidores de PCSK9 , Anticolesterolemiantes/efectos adversos , Anticolesterolemiantes/economía , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/economía , Enfermedades Cardiovasculares/economía , Análisis Costo-Beneficio , Documentación , Costos de los Medicamentos , Grupos Focales , Humanos , Hiperlipoproteinemia Tipo II/economía , Cumplimiento de la Medicación , Calidad de la Atención de Salud , Encuestas y Cuestionarios , Resultado del Tratamiento , Estados Unidos
17.
Dis Model Mech ; 13(10)2020 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-33106318

RESUMEN

The global burden of neurodegenerative diseases underscores the urgent need for innovative strategies to define new drug targets and disease-modifying factors. The nematode Caenorhabditis elegans has served as the experimental subject for multiple transformative discoveries that have redefined our understanding of biology for ∼60 years. More recently, the considerable attributes of C. elegans have been applied to neurodegenerative diseases, including amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease and Huntington's disease. Transgenic nematodes with genes encoding normal and disease variants of proteins at the single- or multi-copy level under neuronal-specific promoters limits expression to select neuronal subtypes. The anatomical transparency of C. elegans affords the use of co-expressed fluorescent proteins to follow the progression of neurodegeneration as the animals age. Significantly, a completely defined connectome facilitates detailed understanding of the impact of neurodegeneration on organismal health and offers a unique capacity to accurately link cell death with behavioral dysfunction or phenotypic variation in vivo Moreover, chemical treatments, as well as forward and reverse genetic screening, hasten the identification of modifiers that alter neurodegeneration. When combined, these chemical-genetic analyses establish critical threshold states to enhance or reduce cellular stress for dissecting associated pathways. Furthermore, C. elegans can rapidly reveal whether lifespan or healthspan factor into neurodegenerative processes. Here, we outline the methodologies employed to investigate neurodegeneration in C. elegans and highlight numerous studies that exemplify its utility as a pre-clinical intermediary to expedite and inform mammalian translational research.


Asunto(s)
Degeneración Nerviosa/patología , Envejecimiento/patología , Animales , Animales Modificados Genéticamente , Conducta Animal , Caenorhabditis elegans , Modelos Animales de Enfermedad , Humanos , Degeneración Nerviosa/genética
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