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1.
J Am Coll Cardiol ; 2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38593947

RESUMEN

BACKGROUND: Most patients with atherosclerotic cardiovascular disease fail to achieve guideline-directed low-density lipoprotein cholesterol (LDL-C) goals. Twice-yearly inclisiran lowers LDL-C by ∼50% when added to statins. OBJECTIVES: This study evaluated the effectiveness of an "inclisiran first" implementation strategy (adding inclisiran immediately upon failure to reach LDL-C <70 mg/dL despite receiving maximally tolerated statins) vs representative usual care in U.S. patients with atherosclerotic cardiovascular disease. METHODS: VICTORION-INITIATE, a prospective, pragmatically designed trial, randomized patients 1:1 to inclisiran (284 mg at days 0, 90, and 270) plus usual care (lipid management at treating physician's discretion) vs usual care alone. Primary endpoints were percentage change in LDL-C from baseline and statin discontinuation rates. RESULTS: We randomized 450 patients (30.9% women, 12.4% Black, 15.3% Hispanic); mean baseline LDL-C was 97.4 mg/dL. The "inclisiran first" strategy led to significantly greater reductions in LDL-C from baseline to day 330 vs usual care (60.0% vs 7.0%; P < 0.001). Statin discontinuation rates with "inclisiran first" (6.0%) were noninferior vs usual care (16.7%). More "inclisiran first" patients achieved LDL-C goals vs usual care (<70 mg/dL: 81.8% vs 22.2%; <55 mg/dL: 71.6% vs 8.9%; P < 0.001). Treatment-emergent adverse event (TEAE) and serious TEAE rates compared similarly between treatment strategies (62.8% vs 53.7% and 11.5% vs 13.4%, respectively). Injection-site TEAEs and TEAEs causing treatment withdrawal occurred more commonly with "inclisiran first" than usual care (10.3% vs 0.0% and 2.6% vs 0.0%, respectively). CONCLUSIONS: An "inclisiran first" implementation strategy led to greater LDL-C lowering compared with usual care without discouraging statin use or raising new safety concerns. (A Randomized, Multicenter, Open-label Trial Comparing the Effectiveness of an "Inclisiran First" Implementation Strategy to Usual Care on LDL Cholesterol [LDL-C] in Patients With Atherosclerotic Cardiovascular Disease and Elevated LDL-C [≥70 mg/dL] Despite Receiving Maximally Tolerated Statin Therapy [VICTORION-INITIATE]; NCT04929249).

2.
Data Brief ; 33: 106332, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33015259

RESUMEN

The data presented in this article are related to the research article entitled "NiCoPt/Graphene-dot Nanosponge as a Highly Stable Electrocatalyst for Efficient Hydrogen Evolution Reaction in Acidic Electrolyte (N.-A. Nguyen et al., 2020) [1]. This article reports a simple method to synthesize NiCoPt/Graphene-dot as an electrocatalyst with low Pt loading but high hydrogen evolution reaction (HER) performance. The morphology of NiCoPt/Graphene-dot was analyzed by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) techniques. The structural and chemical properties of NiCoPt/Graphene-dot were investigated by using X-ray Powder Diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques.

3.
J Adv Vet Anim Res ; 6(3): 425-430, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31583241

RESUMEN

OBJECTIVE: The objective of this study was to develop a low-cost kit for the detection of subclinical mastitis (SCM) and to check its validity, reproducibility, and efficacy at the field level. MATERIALS AND METHODS: A total of 550 quarter milk samples from crossbred dairy cows were collected, of which 400 milk samples were used to validate the newly developed BLRI mastitis test (BMT) kit to justify its efficacy as an individual test kit in detecting SCM based on somatic cell count (SCC) by direct microscopic count (DMC). The efficacy of the newly developed BMT was compared with the California Mastitis Test (CMT) kit. Another 150 milk samples were subjected to SCC determined by DMC and DCC (De Laval cell counter®) categorized by CMT and BMT scores. RESULTS: A SCM test kit, namely, BMT kit was successfully developed in this study. The percentage accuracy of CMT and BMT were 76.75% and 75.75%; sensitivity 69.36% and 67.56%; specificity 85.95% and 85.85%; positive predictive value 86.03% and 85.71%; negative predictive value 69.23% and 68%, respectively. A p value of 0.001 was found for both CMT and BMT. However, CMT and BMT had no significant difference in sensitivity (p = 0.778). Average SCCs (cells/ml) determined by DCC and DMC, respectively, were mostly corresponded to the SCC ranges of both CMT and BMT scores. CONCLUSION: The newly developed BMT kit is an independent, cheap, farmer-friendly, first country made, and reliable SCM diagnostic test kit that can be used at field condition.

4.
Environ Sci Pollut Res Int ; 26(18): 18804-18813, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31062241

RESUMEN

Fish assemblage structure in Panchet, a large tropical reservoir along river Damodar, major tributary of river Ganga in India, was studied along the spatial gradient of the impoundment. Fish samples were collected bimonthly from October 2014 to September 2016. Fish community structure in terms of species composition, relative abundance, and trophic and conservation status was recorded. Spatial fish diversity was analyzed from riverine, transitional, and lacustrine zones. Sixty-two fish species were recorded wherein the family Cyprinidae dominated in number of species (26) followed by Bagridae (5). Shannon diversity index, evenness index, and species richness did not reveal significant variation (p > 0.05) across different zones. Relative abundance of individuals and species richness were maximum in the transitional zone and minimum in the lacustrine zone. Multi-dimensional scaling of fish assemblage revealed similar pattern in the riverine and transitional zones. Trophic guild of fishes indicated dominance of carnivorous species followed by planktivores. Conservation status (IUCN 2017.3) showed 4 fish species in Near Threatened category. The study suggests conservation of fish habitats to maintain diversity and sustained production. The baseline information generated in the study will be beneficial for monitoring the alteration in fish assemblage, conservation of fish diversity, and management planning.


Asunto(s)
Peces/clasificación , Lagos , Ríos , Animales , Biodiversidad , Ecosistema , Explotaciones Pesqueras , Peces/crecimiento & desarrollo , Cadena Alimentaria , India , Densidad de Población , Dinámica Poblacional , Estaciones del Año
5.
Sci Rep ; 8(1): 9251, 2018 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-29915328

RESUMEN

MicroRNAs (miRs) are 18~23 nucleotides long non-coding RNAs that regulate gene expression. To explore whether miR alterations in tauopathy contribute to pathological conditions, we first determined which hippocampal miRs are altered at the presymptomatic and symptomatic stages of tauopathy using rTg4510 mice (Tau mice), a well-characterized tauopathy model. miR-RNA pairing analysis using QIAGEN Ingenuity Pathway Analysis (IPA) revealed 401 genes that can be regulated by 71 miRs altered in Tau hippocampi at the presymptomatic stage. Among several miRs confirmed with real-time qPCR, miR142 (-3p and -5p) in Tau hippocampi were significantly upregulated by two-weeks of age and onward. Transcriptome studies by RNAseq and IPA revealed several overlapping biological and disease associated pathways affected by either Tau or miR142 overexpression, including Signal Transducer and Activator of Transcription 3 (Stat3) and Tumor Necrosis Factor Receptor 2 (Tnfr2) signaling pathways. Similar to what was observed in Tau brains, overexpressing miR142 in wildtype cortical neurons augments mRNA levels of Glial Fibrillary Acidic Protein (Gfap) and Colony Stimulating Factor 1 (Csf1), accompanied by a significant increase in microglia and reactive astrocyte numbers. Taken together, our study suggests that miR alterations by Tau overexpression may contribute to the neuroinflammation observed in Tau brains.


Asunto(s)
MicroARNs/metabolismo , Tauopatías/genética , Proteínas tau/metabolismo , Envejecimiento/genética , Animales , Femenino , Redes Reguladoras de Genes , Hipocampo/metabolismo , Humanos , Ratones Endogámicos ICR , Ratones Transgénicos , MicroARNs/genética , Microglía/metabolismo , Neuronas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transcripción Genética , Transcriptoma/genética , Regulación hacia Arriba/genética
6.
J Coll Physicians Surg Pak ; 27(8): 511-513, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28903847

RESUMEN

Acute liver failure (ALF) is an acute medical emergency which carries high mortality without liver transplantation. Various hepatotropic viruses, drug induced liver injury, auto immune hepatitis, and metabolic liver diseases are the commonly implicated etiologic agents. Liver involvement in dengue hemorrhagic fever (DHF) is quite common, but acute liver failure is its rare complication. Neurological complications are also commonly seen in DHF. Ateenage girl presented with high grade fever and subconjunctival hemorrhage, and later developed jaundice due to acute liver failure. Liver transplantation could not be offered due to fungemia. During hospital stay, she had seizures and intracranial hemorrhage culminating in brain death. ALF with neurological involvement is a rare but very important and fatal complication of DHF; and it should be considered as a cause of acute liver failure, especially in endemic areas.


Asunto(s)
Enfermedades de la Conjuntiva/complicaciones , Hepatitis/diagnóstico por imagen , Ictericia/complicaciones , Fallo Hepático Agudo/etiología , Dengue Grave/diagnóstico , Adolescente , Antivirales/uso terapéutico , Resultado Fatal , Femenino , Hepatitis/tratamiento farmacológico , Humanos , Dengue Grave/complicaciones
8.
Sci Rep ; 7: 43846, 2017 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-28266613

RESUMEN

Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) is a key neuronal maintenance factor and provides potent neuroprotection in numerous preclinical models of neurological disorders. NMNAT2 is significantly reduced in Alzheimer's, Huntington's, Parkinson's diseases. Here we developed a Meso Scale Discovery (MSD)-based screening platform to quantify endogenous NMNAT2 in cortical neurons. The high sensitivity and large dynamic range of this NMNAT2-MSD platform allowed us to screen the Sigma LOPAC library consisting of 1280 compounds. This library had a 2.89% hit rate, with 24 NMNAT2 positive and 13 negative modulators identified. Western analysis was conducted to validate and determine the dose-dependency of identified modulators. Caffeine, one identified NMNAT2 positive-modulator, when systemically administered restored NMNAT2 expression in rTg4510 tauopathy mice to normal levels. We confirmed in a cell culture model that four selected positive-modulators exerted NMNAT2-specific neuroprotection against vincristine-induced cell death while four selected NMNAT2 negative modulators reduced neuronal viability in an NMNAT2-dependent manner. Many of the identified NMNAT2 positive modulators are predicted to increase cAMP concentration, suggesting that neuronal NMNAT2 levels are tightly regulated by cAMP signaling. Taken together, our findings indicate that the NMNAT2-MSD platform provides a sensitive phenotypic screen to detect NMNAT2 in neurons.


Asunto(s)
Corteza Cerebral/citología , Ensayos Analíticos de Alto Rendimiento/métodos , Neuronas/efectos de los fármacos , Nicotinamida-Nucleótido Adenililtransferasa/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Cafeína/farmacología , Supervivencia Celular/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/farmacología , Corteza Cerebral/metabolismo , Expresión Génica/efectos de los fármacos , Ratones Noqueados , Ratones Transgénicos , Neuronas/metabolismo , Nicotinamida-Nucleótido Adenililtransferasa/genética , Reproducibilidad de los Resultados , Tauopatías/genética , Tauopatías/metabolismo
9.
PLoS Biol ; 14(6): e1002472, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27254664

RESUMEN

Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) is neuroprotective in numerous preclinical models of neurodegeneration. Here, we show that brain nmnat2 mRNA levels correlate positively with global cognitive function and negatively with AD pathology. In AD brains, NMNAT2 mRNA and protein levels are reduced. NMNAT2 shifts its solubility and colocalizes with aggregated Tau in AD brains, similar to chaperones, which aid in the clearance or refolding of misfolded proteins. Investigating the mechanism of this observation, we discover a novel chaperone function of NMNAT2, independent from its enzymatic activity. NMNAT2 complexes with heat shock protein 90 (HSP90) to refold aggregated protein substrates. NMNAT2's refoldase activity requires a unique C-terminal ATP site, activated in the presence of HSP90. Furthermore, deleting NMNAT2 function increases the vulnerability of cortical neurons to proteotoxic stress and excitotoxicity. Interestingly, NMNAT2 acts as a chaperone to reduce proteotoxic stress, while its enzymatic activity protects neurons from excitotoxicity. Taken together, our data indicate that NMNAT2 exerts its chaperone or enzymatic function in a context-dependent manner to maintain neuronal health.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Encéfalo/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , Nicotinamida-Nucleótido Adenililtransferasa/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/fisiopatología , Animales , Western Blotting , Encéfalo/patología , Encéfalo/fisiopatología , Células COS , Células Cultivadas , Chlorocebus aethiops , Cognición/fisiología , Femenino , Proteínas HSP90 de Choque Térmico/genética , Humanos , Masculino , Ratones Transgénicos , Microscopía Fluorescente , Persona de Mediana Edad , Chaperonas Moleculares/genética , Mutación , Neuronas/citología , Neuronas/metabolismo , Nicotinamida-Nucleótido Adenililtransferasa/genética , Unión Proteica , Pliegue de Proteína , Estabilidad Proteica , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
10.
PLoS One ; 11(1): e0147620, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26808812

RESUMEN

Nicotinamide mononucleotide adenylyl transferases (NMNATs) are essential neuronal maintenance factors postulated to preserve neuronal function and protect against axonal degeneration in various neurodegenerative disease states. We used in vitro and in vivo approaches to assess the impact of NMNAT2 reduction on cellular and physiological functions induced by treatment with a vinca alkaloid (vincristine) and a taxane-based (paclitaxel) chemotherapeutic agent. NMNAT2 null (NMNAT2-/-) mutant mice die at birth and cannot be used to probe functions of NMNAT2 in adult animals. Nonetheless, primary cortical cultures derived from NMNAT2-/- embryos showed reduced cell viability in response to either vincristine or paclitaxel treatment whereas those derived from NMNAT2 heterozygous (NMNAT2+/-) mice were preferentially sensitive to vincristine-induced degeneration. Adult NMNAT2+/- mice, which survive to adulthood, exhibited a 50% reduction of NMNAT2 protein levels in dorsal root ganglia relative to wildtype (WT) mice with no change in levels of other NMNAT isoforms (NMNAT1 or NMNAT3), NMNAT enzyme activity (i.e. NAD/NADH levels) or microtubule associated protein-2 (MAP2) or neurofilament protein levels. We therefore compared the impact of NMNAT2 knockdown on the development and maintenance of chemotherapy-induced peripheral neuropathy induced by vincristine and paclitaxel treatment using NMNAT2+/- and WT mice. NMNAT2+/- did not differ from WT mice in either the development or maintenance of either mechanical or cold allodynia induced by either vincristine or paclitaxel treatment. Intradermal injection of capsaicin, the pungent ingredient in hot chili peppers, produced equivalent hypersensitivity in NMNAT2+/- and WT mice receiving vehicle in lieu of paclitaxel. Capsaicin-evoked hypersensitivity was enhanced by prior paclitaxel treatment but did not differ in either NMNAT2+/- or WT mice. Thus, capsaicin failed to unmask differences in nociceptive behaviors in either paclitaxel-treated or paclitaxel-untreated NMNAT2+/- and WT mice. Moreover, no differences in motor behavior were detected between genotypes in the rotarod test. Our studies do not preclude the possibility that complete knockout of NMNAT2 in a conditional knockout animal could unmask a role for NMNAT2 in protection against detrimental effects of chemotherapeutic treatment.


Asunto(s)
Nicotinamida-Nucleótido Adenililtransferasa/genética , Nicotinamida-Nucleótido Adenililtransferasa/metabolismo , Enfermedades del Sistema Nervioso Periférico/enzimología , Enfermedades del Sistema Nervioso Periférico/genética , Animales , Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Femenino , Ratones , Ratones Mutantes , Paclitaxel/farmacología , Embarazo , Vincristina/farmacología
11.
Curr Pharm Des ; 22(5): 549-65, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26601968

RESUMEN

Diabetes mellitus (DM) is one of the most common endocrine metabolic disorders. In addition to exercise and diet, oral anti-diabetic drugs have been used as a part of the management strategy worldwide. Unfortunately, none of the conventional anti-diabetic drugs are without side effects, and these drugs pose an economic burden. Therefore, the investigation of novel anti-diabetic regimens is a major challenge for researchers, in which nature has been the primary resource for the discovery of potential therapeutics. Many plants have been shown to act as anti-diabetic agents, in which the main active constituents are believed to be polyphenols. Natural products containing high polyphenol levels can control carbohydrate metabolism by various mechanisms, such as protecting and restoring beta-cell integrity, enhancing insulin releasing activity, and increasing cellular glucose uptake. Blackberries, red grapes, apricots, eggplant and popular drinks such as coffee, cocoa and green tea are all rich in polyphenols, which may dampen insulin resistance and be natural alternatives in the treatment of diabetes. Therefore, the aim of this review is to report on the available anti-diabetic polyphenols (medicinal plants, fruits and vegetables), their mechanisms in the various pathways of DM and their correlations with DM. Additionally, this review emphasizes the types of polyphenols that could be potential future resources in the treatment of DM via either novel regimens or as supplementary agents.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Polifenoles/uso terapéutico , Animales , Humanos
12.
Compr Rev Food Sci Food Saf ; 15(1): 219-233, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33371579

RESUMEN

Honey is a popular natural food product with a very complex composition mainly consisting of both organic and inorganic constituents. The composition of honey is strongly influenced by both natural and anthropogenic factors, which vary based on its botanical and geographical origins. Although minerals and heavy metals are minor constituents of honey, they play vital role in determining its quality. There are several different analytical methods used to determine the chemical elements in honey. These methods are typically based on spectroscopy or spectrometry techniques (including atomic absorption spectrometry, atomic emission spectrometry, inductively coupled plasma mass spectrometry, and inductively coupled plasma optical emission spectrometry). This review compiles available scientific information on minerals and heavy metals in honey reported from all over the world. To date, 54 chemical elements in various types of honey have been identified and can be divided into 3 groups: major or macroelements (Na, K, Ca, Mg, P, S, Cl), minor or trace elements (Al, Cu, Pb, Zn, Mn, Cd, Tl, Co, Ni, Rb, Ba, Be, Bi, U, V, Fe, Pt, Pd, Te, Hf, Mo, Sn, Sb, La, I, Sm, Tb, Dy, Sd, Th, Pr, Nd, Tm, Yb, Lu, Gd, Ho, Er, Ce, Cr, As, B, Br, Cd, Hg, Se, Sr), and heavy metals (trace elements that have a specific gravity at least 5 times higher than that of water and inorganic sources). Chemical elements in honey samples throughout the world vary in terms of concentrations and are also influenced by environmental pollution.

13.
J Neurosci ; 35(21): 8118-31, 2015 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-26019329

RESUMEN

The age-dependent progression of tau pathology is a major characteristic of tauopathies, including Alzheimer's disease (AD), and plays an important role in the behavioral phenotypes of AD, including memory deficits. Despite extensive molecular and cellular studies on tau pathology, it remains to be determined how it alters the neural circuit functions underlying learning and memory in vivo. In rTg4510 mice, a Tau-P301L tauopathy model, hippocampal place fields that support spatial memories are abnormal at old age (7-9 months) when tau tangles and neurodegeneration are extensive. However, it is unclear how the abnormality in the hippocampal circuit function arises and progresses with the age-dependent progression of tau pathology. Here we show that in young (2-4 months of age) rTg4510 mice, place fields of hippocampal CA1 cells are largely normal, with only subtle differences from those of age-matched wild-type control mice. Second, high-frequency ripple oscillations of local field potentials in the hippocampal CA1 area are significantly reduced in young rTg4510 mice, and even further deteriorated in old rTg4510 mice. The ripple reduction is associated with less bursty firing and altered synchrony of CA1 cells. Together, the data indicate that deficits in ripples and neuronal synchronization occur before overt deficits in place fields in these mice. The results reveal a tau-pathology-induced progression of hippocampal functional changes in vivo.


Asunto(s)
Modelos Animales de Enfermedad , Progresión de la Enfermedad , Hipocampo/fisiopatología , Neuronas , Tauopatías/fisiopatología , Animales , Femenino , Hipocampo/patología , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Transgénicos , Neuronas/patología , Tauopatías/patología
14.
Neuroimage Clin ; 4: 711-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24936422

RESUMEN

BACKGROUND: Axonal transport is vital for neurons and deficits in this process have been previously reported in a few mouse models of Alzheimer's disease prior to the appearance of plaques and tangles. However, it remains to be determined whether axonal transport is defective prior to the onset of neurodegeneration. The rTg4510 mouse, a fronto-temporal dementia and parkinsonism-17 (FTDP-17) tauopathy model, over-express tau-P301L mutation found in familial forms of FTDP-17, in the forebrain driven by the calcium-calmodulin kinase II promoter. This mouse model exhibits tau pathology, neurodegeneration in the forebrain, and associated behavioral deficits beginning at 4-5 months of age. ANIMAL MODEL: rTg4510 transgenic mice were used in these studies. Mice were given 2 µL of MnCl2 in each nostril 1 h prior to Magnetic Resonance Imaging (MRI). Following MnCl2 nasal lavage, mice were imaged using Manganese enhanced Magnetic Resonance Imaging (MEMRI) Protocol with TE = 8.5 ms, TR = 504 ms, FOV = 3.0 cm, matrix size = 128 × 128 × 128, number of cycles = 15 with each cycle taking approximately 2 min, 9 s, and 24 ms using Paravision software (BrukerBioSpin, Billerica, MA). During imaging, body temperature was maintained at 37.0 °C using an animal heating system (SA Instruments, Stony Brook, NY). DATA ANALYSIS: Resulting images were analyzed using Paravision software. Regions of interest (ROI) within the olfactory neuronal layer (ONL) and the water phantom consisting of one pixel (ONL) and 9 pixels (water) were selected and copied across each of the 15 cycles. Signal intensities (SI) of ONL and water phantom ROIs were measured. SI values obtained for ONL were then normalized the water phantom SI values. The correlation between normalized signal intensity in the ONL and time were assessed using Prism (GraphPad Software, San Diego, CA). RESULTS: Using the MEMRI technique on 1.5, 3, 5, and 10-month old rTg4510 mice and littermate controls, we found significant axonal transport deficits present in the rTg4510 mice beginning at 3 months of age in an age-dependent manner. Using linear regression analysis, we measured rates of axonal transport at 1.5, 3, 5, and 10 months of age in rTg4510 and WT mice. Axonal transport rates were observed in rTg4510 mice at 48% of WT levels at 3 months, 40% of WT levels at 5 months, and 30% of WT levels at 10 months of age. In order to determine the point at which tau appears in the cortex, we probed for phosphorylated tau levels, and found that pSer262 is present at 3 months of age, not earlier at 1.5 months of age, but observed no pathological tau species until 6 months of age, months after the onset of the transport deficits. In addition, we saw localization of tau in the ONL at 6 months of age. DISCUSSION: In our study, we identified the presence of age-dependent axonal transport deficits beginning at 3 months of age in rTg4510 mice. We correlated these deficits at 3 months to the presence of hyperphosphorylated tau in the brain and the presence within the olfactory epithelium. We observed tau pathology not only in the soma of these neurons but also within the axons and processes of these neurons. Our characterization of axonal transport in this tauopathy model provides a functional time point that can be used for future therapeutic interventions.


Asunto(s)
Transporte Axonal/fisiología , Axones/metabolismo , Encéfalo/patología , Demencia Frontotemporal/patología , Vías Olfatorias/patología , Proteínas tau/metabolismo , Factores de Edad , Animales , Modelos Animales de Enfermedad , Demencia Frontotemporal/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Ratones , Ratones Transgénicos , Mutación/genética , Proteína Marcadora Olfativa/metabolismo , Factores de Tiempo , Proteínas tau/genética
15.
Trends Neurosci ; 36(11): 632-40, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23968695

RESUMEN

Proper brain function requires neuronal homeostasis over a range of environmental challenges. Neuronal activity, injury, and aging stress the nervous system, and lead to neuronal dysfunction and degeneration. Nevertheless, most organisms maintain healthy neurons throughout life, implying the existence of active maintenance mechanisms. Recent studies have revealed a key neuronal maintenance and protective function for nicotinamide mononucleotide adenylyl transferases (NMNATs). We review evidence that NMNATs protect neurons through multiple mechanisms in different contexts, and highlight functions that either require or are independent of NMNAT catalytic activity. We then summarize data supporting a role for NMNATs in neuronal maintenance and raise intriguing questions on how NMNATs preserve neuronal integrity and facilitate proper neural function throughout life.


Asunto(s)
Evolución Molecular , Degeneración Nerviosa/metabolismo , Neuronas/metabolismo , Mononucleótido de Nicotinamida/metabolismo , Nucleotidiltransferasas/metabolismo , Animales , Biocatálisis , Humanos , Degeneración Nerviosa/patología , Neuronas/patología
16.
EMBO Rep ; 14(1): 87-94, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23154466

RESUMEN

Active zones are specialized presynaptic structures critical for neurotransmission. We show that a neuronal maintenance factor, nicotinamide mononucleotide adenylyltransferase (NMNAT), is required for maintaining active zone structural integrity in Drosophila by interacting with the active zone protein, Bruchpilot (BRP), and shielding it from activity-induced ubiquitin-proteasome-mediated degradation. NMNAT localizes to the peri-active zone and interacts biochemically with BRP in an activity-dependent manner. Loss of NMNAT results in ubiquitination, mislocalization and aggregation of BRP, and subsequent active zone degeneration. We propose that, as a neuronal maintenance factor, NMNAT specifically maintains active zone structure by direct protein-protein interaction.


Asunto(s)
Proteínas de Drosophila/genética , Drosophila/genética , Nicotinamida-Nucleótido Adenililtransferasa/genética , Terminales Presinápticos/enzimología , Animales , Drosophila/enzimología , Proteínas de Drosophila/metabolismo , Regulación de la Expresión Génica , Nicotinamida-Nucleótido Adenililtransferasa/antagonistas & inhibidores , Nicotinamida-Nucleótido Adenililtransferasa/metabolismo , Terminales Presinápticos/ultraestructura , Complejo de la Endopetidasa Proteasomal , Unión Proteica , Proteolisis , ARN Interferente Pequeño/genética , Transducción de Señal , Transmisión Sináptica/fisiología , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitinación
17.
J Orthop Surg (Hong Kong) ; 20(3): 371-4, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23255650

RESUMEN

PURPOSE: To compare early outcome of transforaminal lumbar interbody fusion (TLIF) for lytic versus degenerative spondylolisthesis. METHODS: 14 women and 8 men aged 20 to 60 (mean, 36) years underwent TLIF for lytic (n=15) or degenerative (n=7) spondylolisthesis. Of the 15 patients with lytic spondylolisthesis, 9 involved L4/ L5 and 6 L5/S1. Of the 7 patients with degenerative spondylolisthesis, 3 involved L4/L5, 2 L5/S1, one L2/L3, and one L3/L4. The spondylolistheses were classified as grade II (n=15), grade III (n=4), and retrolisthesis (n=3). 11 patients with lytic and 2 with degenerative spondylolisthesis had sensory deficits (n=12), motor deficits (n=9), and diminished reflexes (n=7). Visual analogue score (VAS) for pain and the Oswestry Disability Index (ODI) of each patient were assessed at months 3, 6, and 12, and 6 monthly thereafter. Fusion status was assessed by radiologists. Comprehensive outcome of each patient was graded as excellent, good, fair, or poor. RESULTS: The mean VAS score for low back pain improved significantly from 7.4 preoperatively to 2.1 at year 1 (p<0.001), as did the mean VAS score for leg pain from 6.7 to 1.4 (p<0.001) and the mean ODI from 67.8% to 11.8% (p<0.001). No patient had any residual neurological deficit, and all achieved radiological fusion. The comprehensive outcome was excellent in 16 patients, good in 5, and fair in one. 16 patients returned to their previous level of activity. CONCLUSION: TLIF is a safe and effective surgical procedure for the treatment of lytic and degenerative spondylolisthesis.


Asunto(s)
Vértebras Lumbares , Fusión Vertebral/métodos , Espondilolistesis/cirugía , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Radiografía , Columna Vertebral/diagnóstico por imagen , Espondilolistesis/diagnóstico por imagen , Adulto Joven
18.
Acta Neuropathol ; 123(6): 825-39, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22426854

RESUMEN

C9ORF72-hexanucleotide repeat expansions and ubiquilin-2 (UBQLN2) mutations are recently identified genetic markers in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). We investigate the relationship between C9ORF72 expansions and the clinical phenotype and neuropathology of ALS and FTLD. Genetic analysis and immunohistochemistry (IHC) were performed on autopsy-confirmed ALS (N = 75), FTLD-TDP (N = 30), AD (N = 14), and controls (N = 11). IHC for neurodegenerative disease pathology consisted of C9ORF72, UBQLN, p62, and TDP-43. A C9ORF72 expansion was identified in 19.4 % of ALS and 31 % of FTLD-TDP cases. ALS cases with C9ORF72 expansions frequently showed a bulbar onset of disease (57 %) and more rapid disease progression to death compared to non-expansion cases. Staining with C9ORF72 antibodies did not yield specific pathology. UBQLN pathology showed a highly distinct pattern in ALS and FTLD-TDP cases with the C9ORF72 expansion, with UBQLN-positive cytoplasmic inclusions in the cerebellar granular layer and extensive UBQLN-positive aggregates and dystrophic neurites in the hippocampal molecular layer and CA regions. These UBQLN pathologies were sufficiently unique to allow correct prediction of cases that were later confirmed to have C9ORF72 expansions by genetic analysis. UBQLN pathology partially co-localized with p62, and to a minor extent with TDP-43 positive dystrophic neurites and spinal cord skein-like inclusions. Our data indicate a pathophysiological link between C9ORF72 expansions and UBQLN proteins in ALS and FTLD-TDP that is associated with a highly characteristic pattern of UBQLN pathology. Our study indicates that this pathology is associated with alterations in clinical phenotype, and suggests that the presence of C9ORF72 repeat expansions may indicate a worse prognosis in ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Proteínas de Ciclo Celular/metabolismo , Degeneración Lobar Frontotemporal/genética , Proteínas/metabolismo , Ubiquitinas/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Edad de Inicio , Anciano , Anciano de 80 o más Años , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/mortalidad , Esclerosis Amiotrófica Lateral/patología , Proteínas Relacionadas con la Autofagia , Proteína C9orf72 , Proteínas de Ciclo Celular/genética , Expansión de las Repeticiones de ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Degeneración Lobar Frontotemporal/mortalidad , Degeneración Lobar Frontotemporal/patología , Humanos , Cuerpos de Inclusión/patología , Masculino , Persona de Mediana Edad , Mutación/genética , Proteínas/genética , Ubiquitinas/genética
19.
Hum Mol Genet ; 21(2): 237-50, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-21965302

RESUMEN

Tauopathies, including Alzheimer's disease, are a group of neurodegenerative diseases characterized by abnormal tau hyperphosphorylation that leads to formation of neurofibrillary tangles. Drosophila models of tauopathy display prominent features of the human disease including compromised lifespan, impairments of learning, memory and locomotor functions and age-dependent neurodegeneration visible as vacuolization. Here, we use a Drosophila model of frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17), in order to study the neuroprotective capacity of a recently identified neuronal maintenance factor, nicotinamide mononucleotide (NAD) adenylyl transferase (NMNAT), a protein that has both NAD synthase and chaperone function. NMNAT is essential for maintaining neuronal integrity under normal conditions and has been shown to protect against several neurodegenerative conditions. However, its protective role in tauopathy has not been examined. Here, we show that overexpression of NMNAT significantly suppresses both behavioral and morphological deficits associated with tauopathy by means of reducing the levels of hyperphosphorylated tau oligomers. Importantly, the protective activity of NMNAT protein is independent of its NAD synthesis activity, indicating a role for direct protein-protein interaction. Next, we show that NMNAT interacts with phosphorylated tau in vivo and promotes the ubiquitination and clearance of toxic tau species. Consequently, apoptosis activation was significantly reduced in brains overexpressing NMNAT, and neurodegeneration was suppressed. Our report on the molecular basis of NMNAT-mediated neuroprotection in tauopathies opens future investigation of this factor in other protein foldopathies.


Asunto(s)
Modelos Animales de Enfermedad , Nicotinamida-Nucleótido Adenililtransferasa/metabolismo , Tauopatías/metabolismo , Proteínas tau/antagonistas & inhibidores , Animales , Drosophila , Fosforilación , Tauopatías/enzimología , Tauopatías/patología , Proteínas tau/metabolismo
20.
Hum Mol Genet ; 21(2): 251-67, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22027994

RESUMEN

Tauopathies, characterized by neurofibrillary tangles (NFTs) of phosphorylated tau proteins, are a group of neurodegenerative diseases, including frontotemporal dementia and both sporadic and familial Alzheimer's disease. Forebrain-specific over-expression of human tau(P301L), a mutation associated with frontotemporal dementia with parkinsonism linked to chromosome 17, in rTg4510 mice results in the formation of NFTs, learning and memory impairment and massive neuronal death. Here, we show that the mRNA and protein levels of NMNAT2 (nicotinamide mononucleotide adenylyltransferase 2), a recently identified survival factor for maintaining neuronal health in peripheral nerves, are reduced in rTg4510 mice prior to the onset of neurodegeneration or cognitive deficits. Two functional cAMP-response elements (CREs) were identified in the nmnat2 promoter region. Both the total amount of phospho-CRE binding protein (CREB) and the pCREB bound to nmnat2 CRE sites in the cortex and the hippocampus of rTg4510 mice are significantly reduced, suggesting that NMNAT2 is a direct target of CREB under physiological conditions and that tau(P301L) overexpression down-regulates CREB-mediated transcription. We found that over-expressing NMNAT2 or its homolog NMNAT1, but not NMNAT3, in rTg4510 hippocampi from 6 weeks of age using recombinant adeno-associated viral vectors significantly reduced neurodegeneration caused by tau(P301L) over-expression at 5 months of age. In summary, our studies strongly support a protective role of NMNAT2 in the mammalian central nervous system. Decreased endogenous NMNAT2 function caused by reduced CREB signaling during pathological insults may be one of underlying mechanisms for neuronal death in tauopathies.


Asunto(s)
Proteína de Unión a CREB/genética , Regulación hacia Abajo , Nicotinamida-Nucleótido Adenililtransferasa/genética , Tauopatías/genética , Transcripción Genética , Animales , Secuencia de Bases , Western Blotting , Cartilla de ADN , Modelos Animales de Enfermedad , Técnica del Anticuerpo Fluorescente , Hipocampo/patología , Humanos , Ratones , Ratones Transgénicos , Regiones Promotoras Genéticas , Reacción en Cadena en Tiempo Real de la Polimerasa , Tauopatías/patología
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