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1.
Cell Mol Life Sci ; 81(1): 55, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38261097

RESUMEN

To investigate the mechanism(s) underlying the expression of primate-specific microRNAs (miRs), we sought DNA regulatory elements and proteins mediating expression of the primate-specific hsa-miR-608 (miR-608), which is located in the SEMA4G gene and facilitates the cholinergic blockade of inflammation by targeting acetylcholinesterase mRNA. 'Humanized' mice carrying pre-miR-608 flanked by 250 bases of endogenous sequences inserted into the murine Sema4g gene successfully expressed miR-608. Moreover, by flanking miR-608 by shortened fragments of its human genome region we identified an active independent promoter within the 150 nucleotides 5' to pre-miR-608, which elevated mature miR-608 levels by 100-fold in transfected mouse- and human-originated cells. This highlighted a regulatory role of the 5' flank as enabling miR-608 expression. Moreover, pull-down of the 150-base 5' sequence revealed its interaction with ribosomal protein L24 (RPL24), implicating an additional mechanism controlling miR-608 levels. Furthermore, RPL24 knockdown altered the expression of multiple miRs, and RPL24 immunoprecipitation indicated that up- or down-regulation of the mature miRs depended on whether their precursors bind RPL24 directly. Finally, further tests showed that RPL24 interacts directly with DDX5, a component of the large microprocessor complex, to inhibit miR processing. Our findings reveal that RPL24, which has previously been shown to play a role in miR processing in Arabidopsis thaliana, has a similar evolutionarily conserved function in miR biogenesis in mammals. We thus characterize a novel extra-ribosomal role of RPL24 in primate miR regulation.


Asunto(s)
MicroARNs , Proteínas Ribosómicas , Animales , Humanos , Ratones , Acetilcolinesterasa , MicroARNs/genética , Primates , Proteínas Ribosómicas/genética
2.
Proc Natl Acad Sci U S A ; 119(49): e2123487119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36454749

RESUMEN

Hexanucleotide G4C2 repeat expansions in the C9orf72 gene are the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Dipeptide repeat proteins (DPRs) generated by translation of repeat-containing RNAs show toxic effects in vivo as well as in vitro and are key targets for therapeutic intervention. We generated human antibodies that bind DPRs with high affinity and specificity. Anti-GA antibodies engaged extra- and intra-cellular poly-GA and reduced aggregate formation in a poly-GA overexpressing human cell line. However, antibody treatment in human neuronal cultures synthesizing exogenous poly-GA resulted in the formation of large extracellular immune complexes and did not affect accumulation of intracellular poly-GA aggregates. Treatment with antibodies was also shown to directly alter the morphological and biochemical properties of poly-GA and to shift poly-GA/antibody complexes to more rapidly sedimenting ones. These alterations were not observed with poly-GP and have important implications for accurate measurement of poly-GA levels including the need to evaluate all centrifugation fractions and disrupt the interaction between treatment antibodies and poly-GA by denaturation. Targeting poly-GA and poly-GP in two mouse models expressing G4C2 repeats by systemic antibody delivery for up to 16 mo was well-tolerated and led to measurable brain penetration of antibodies. Long-term treatment with anti-GA antibodies produced improvement in an open-field movement test in aged C9orf72450 mice. However, chronic administration of anti-GA antibodies in AAV-(G4C2)149 mice was associated with increased levels of poly-GA detected by immunoassay and did not significantly reduce poly-GA aggregates or alleviate disease progression in this model.


Asunto(s)
Genes Reguladores , Poli A , Animales , Humanos , Ratones , Complejo Antígeno-Anticuerpo , Proteína C9orf72/genética , Dipéptidos , Modelos Animales de Enfermedad
3.
Proc Natl Acad Sci U S A ; 114(25): E4996-E5005, 2017 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-28584127

RESUMEN

Epilepsy is a common neurological disease, manifested in unprovoked recurrent seizures. Epileptogenesis may develop due to genetic or pharmacological origins or following injury, but it remains unclear how the unaffected brain escapes this susceptibility to seizures. Here, we report that dynamic changes in forebrain microRNA (miR)-211 in the mouse brain shift the threshold for spontaneous and pharmacologically induced seizures alongside changes in the cholinergic pathway genes, implicating this miR in the avoidance of seizures. We identified miR-211 as a putative attenuator of cholinergic-mediated seizures by intersecting forebrain miR profiles that were Argonaute precipitated, synaptic vesicle target enriched, or differentially expressed under pilocarpine-induced seizures, and validated TGFBR2 and the nicotinic antiinflammatory acetylcholine receptor nAChRa7 as murine and human miR-211 targets, respectively. To explore the link between miR-211 and epilepsy, we engineered dTg-211 mice with doxycycline-suppressible forebrain overexpression of miR-211. These mice reacted to doxycycline exposure by spontaneous electrocorticography-documented nonconvulsive seizures, accompanied by forebrain accumulation of the convulsive seizures mediating miR-134. RNA sequencing demonstrated in doxycycline-treated dTg-211 cortices overrepresentation of synaptic activity, Ca2+ transmembrane transport, TGFBR2 signaling, and cholinergic synapse pathways. Additionally, a cholinergic dysregulated mouse model overexpressing a miR refractory acetylcholinesterase-R splice variant showed a parallel propensity for convulsions, miR-211 decreases, and miR-134 elevation. Our findings demonstrate that in mice, dynamic miR-211 decreases induce hypersynchronization and nonconvulsive and convulsive seizures, accompanied by expression changes in cholinergic and TGFBR2 pathways as well as in miR-134. Realizing the importance of miR-211 dynamics opens new venues for translational diagnosis of and interference with epilepsy.


Asunto(s)
Encéfalo/metabolismo , Epilepsia/metabolismo , MicroARNs/metabolismo , Acetilcolina/farmacología , Acetilcolinesterasa/metabolismo , Animales , Encéfalo/efectos de los fármacos , Colinérgicos/farmacología , Epilepsia/tratamiento farmacológico , Humanos , Ratones , Ratones Transgénicos , Pilocarpina/farmacología , Receptores Nicotínicos/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Convulsiones/metabolismo
4.
Retina ; 37(2): 344-349, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28118284

RESUMEN

PURPOSE: To evaluate the role of serum urea and creatinine as surrogate markers for disruption of retinal photoreceptor external limiting membrane (ELM) and inner segment ellipsoid zone (EZ) in Type 2 diabetic retinopathy (DR) using spectral-domain optical coherence tomography, for the first time. METHODS: One hundred and seventeen consecutive cases of Type 2 diabetes mellitus (diabetes without retinopathy [No DR; n = 39], nonproliferative diabetic retinopathy [NPDR; n = 39], proliferative diabetic retinopathy [PDR; n = 39]) and 40 healthy control subjects were included. Serum levels of urea and creatinine were assessed using standard protocol. Spectral-domain optical coherence tomography was used to grade the disruption of ELM and EZ as follows: Grade 0, no disruption of ELM and EZ; Grade 1, ELM disrupted, EZ intact; Grade 2, ELM and EZ disrupted. Data were analyzed statistically. RESULTS: Increase in serum levels of urea (F = 22.93) and creatinine (F = 15.82) and increased grades of disruption of ELM and EZ (γ = 116.3) were observed with increased severity of DR (P < 0.001). Increase in serum levels of urea (F = 10.45) and creatinine (F = 6.89) was observed with increased grades of disruption of ELM and EZ (P = 0.001). CONCLUSION: Serum levels of urea and creatinine are surrogate markers for disruption of retinal photoreceptor ELM and EZ on spectral-domain optical coherence tomography in DR.


Asunto(s)
Creatinina/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/patología , Retinopatía Diabética/sangre , Retinopatía Diabética/patología , Membrana Epirretinal/patología , Segmento Interno de las Células Fotorreceptoras Retinianas/patología , Urea/sangre , Adulto , Anciano , Análisis de Varianza , Biomarcadores/sangre , Estudios de Casos y Controles , Retinopatía Diabética/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Células Fotorreceptoras de Vertebrados/patología , Enfermedades de la Retina , Índice de Severidad de la Enfermedad
5.
Horm Behav ; 79: 70-3, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26435474

RESUMEN

Tamoxifen (TMX) is a selective estrogen receptor modulator (SERM) used in the treatment of breast cancer. Earlier studies show its neuroprotection via regulating apoptosis, microglial functions, and synaptic plasticity. TMX also showed memory enhancement in ovariectomized mice, and protection from amyloid induced damage in hippocampal cell line. These reports encouraged us to explore the role of TMX in relevance to Alzheimer's disease (AD). We report here, the effect of TMX treatment a) on memory, and b) levels of neurotransmitters (acetylcholine (ACh) and dopamine (DA)) in breeding-retired-female mice injected with beta amyloid1-42 (Aß1-42). Mice were treated with TMX (10mg/kg, i.p.) for 15 days. In Morris water maze test, the TMX treated mice escape latency decreased during training trials. They also spent longer time in the platform quadrant on probe trial, compared to controls. In Passive avoidance test, TMX treated mice avoided stepping on the shock chamber. This suggests that TMX protects memory from Aß induced toxicity. In frontal cortex, ACh was moderately increased, with TMX treatment. In striatum, dopamine was significantly increased, 3,4-dihydroxyphenylacetic acid (DOPAC) level and DOPAC/DA ratio was decreased post TMX treatment. Therefore, TMX enhances spatial and contextual memory by reducing dopamine metabolism and increasing ACh level in Aß1-42 injected-breeding-retired-female mice.


Asunto(s)
Enfermedad de Alzheimer/patología , Amiloidosis/patología , Memoria/efectos de los fármacos , Tamoxifeno/farmacología , Ácido 3,4-Dihidroxifenilacético/farmacología , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides , Amiloidosis/inducido químicamente , Amiloidosis/psicología , Animales , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Cuerpo Estriado/patología , Modelos Animales de Enfermedad , Dopamina/metabolismo , Femenino , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/patología , Ratones , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Neostriado/patología , Moduladores Selectivos de los Receptores de Estrógeno/farmacología
6.
Clin Exp Ophthalmol ; 43(5): 429-36, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25675974

RESUMEN

BACKGROUND: The aim of the study was to determine plasma nitric oxide (NO) and lipid peroxide (LPO) levels in diabetic retinopathy and its association with severity of disease. DESIGN: Prospective observational study. PARTICIPANTS: A total of 60 consecutive cases and 20 healthy controls were included. METHODS: Severity of retinopathy was graded according to early treatment diabetic retinopathy study (ETDRS) classification. Photoreceptor inner segment ellipsoid band (ISel) disruption and retinal pigment epithelium (RPE) alteration were graded using spectral domain optical coherence tomography. Data were statistically analyzed. MAIN OUTCOME MEASURES: Plasma thiobarbituric acid reactive substances, NO assay and reduced glutathione (GSH) were measured using standard protocol. RESULTS: Increased severity of diabetic retinopathy was significantly associated with increase in plasma levels of LPO (P < 0.05), NO (P < 0.001) and decrease in plasma levels of GSH (P < 0.0001), ISel disruption (P < 0.001) and RPE topographic alteration (P < 0.01). CONCLUSION: Increased plasma NO levels are associated with increased severity of diabetic retinopathy. For the first time, it has been demonstrated that increased plasma LPO, NO and decreased GSH levels are associated with in vivo structural changes in inner segment ellipsoid and RPE.


Asunto(s)
Retinopatía Diabética/fisiopatología , Peróxidos Lipídicos/sangre , Óxido Nítrico/sangre , Estrés Oxidativo , Segmento Interno de las Células Fotorreceptoras Retinianas/patología , Epitelio Pigmentado de la Retina/patología , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Glutatión/sangre , Humanos , Peroxidación de Lípido , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Tomografía de Coherencia Óptica
7.
Bioorg Med Chem Lett ; 23(3): 702-5, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23276831

RESUMEN

MAO-B and AChE are the two validated targets for Alzheimer's disease. In pursuit of a single molecule hitting both the targets, we explored a set of previously reported extremely potent MAO-B selective inhibitors, for their additional AChE inhibitory activity. We performed molecular docking studies that formed the basis for in vitro enzyme assay, and provided necessary insights into their binding mode. Most of the compounds were found active at nano molar range, and are consistent with the docking results. The identified dual acting lead molecules may provide the basis for further exploring these chemical moieties.


Asunto(s)
Acetilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/farmacología , Monoaminooxidasa/metabolismo , Pirazoles/síntesis química , Sitios de Unión , Inhibidores de la Colinesterasa/química , Activación Enzimática/efectos de los fármacos , Humanos , Modelos Moleculares , Estructura Molecular , Pirazoles/química , Pirazoles/farmacología
8.
ALTEX ; 39(4): 560-582, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35502629

RESUMEN

Drug-induced neurotoxicity is a leading cause of safety-related attrition for therapeutics in clinical trials, often driven by poor predictivity of preclinical in vitro and in vivo models of neurotoxicity. Over a dozen different iPSC-derived 3D spheroids have been described in recent years, but their ability to predict neurotoxicity in patients has not been evaluated nor compared with the predictive power of nonclinical species. To assess the predictive capabilities of human iPSC-derived neural spheroids (microBrains), we used 84 structurally diverse pharmaceuticals with robust clinical and pre-clinical datasets with varying degrees of seizurogenic and neurodegenerative liability. Drug-induced changes in neural viability and phenotypic calcium bursts were assessed using 7 endpoints based on calcium oscillation profiles and cel-lular ATP levels. These endpoints, normalized by therapeutic exposure, were used to build logistic regression models to establish endpoint cutoffs and evaluate probability for clinical neurotoxicity. The neurotoxicity score calculated from the logistic regression model could distinguish neurotoxic from non-neurotoxic clinical molecules with a specificity as high as 93.33% and a sensitivity of 53.49%, demonstrating a very low false positive rate for the prediction of seizures, convulsions, and neurodegeneration. In contrast, nonclinical species showed a higher sensitivity (75%) but much lower specificity (30.4%). The neural spheroids demonstrated higher likelihood ratio positive and inverse likelihood ratio neg-ative values compared with nonclinical safety studies. This assay has the potential to be used as a predictive assay to detect neurotoxicity in early drug discovery, aiding in the early identification of compounds that eventually may fail due to neurotoxicity.


Asunto(s)
Células Madre Pluripotentes Inducidas , Síndromes de Neurotoxicidad , Humanos , Síndromes de Neurotoxicidad/etiología , Convulsiones/inducido químicamente , Señalización del Calcio , Preparaciones Farmacéuticas
9.
Bioorg Med Chem Lett ; 21(7): 1969-73, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21377879

RESUMEN

In an effort to develop selective MAO (monoamine oxidase) B inhibitors, structure based virtual screening was initiated on an in-house library. Top 10 HITS were synthesized and evaluated for MAO (A and B) inhibitory activity, both against human and rat enzymes. All the compounds were found selective, reversible and active in nM range (100 times more potent than selegeline) towards MAO-B. Outstanding co-relation between predicted and experimental K(i) values were observed.


Asunto(s)
Inhibidores de la Monoaminooxidasa/farmacología , Monoaminooxidasa/efectos de los fármacos , Pirazoles/farmacología , Animales , Técnicas Químicas Combinatorias , Evaluación Preclínica de Medicamentos , Humanos , Modelos Moleculares , Inhibidores de la Monoaminooxidasa/síntesis química , Inhibidores de la Monoaminooxidasa/química , Pirazoles/síntesis química , Pirazoles/química , Ratas
10.
Indian J Ophthalmol ; 69(11): 3199-3202, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34708772

RESUMEN

PURPOSE: Advanced glycation end products (AGEs), due to increased production and a slow turnover rate, serve as mediators of "metabolic memory" even after the resolution of hyperglycemia. A prospective study was undertaken to evaluate the association of AGEs with subfoveal ellipsoid zone (EZ) disruption in diabetic macular edema (DME). METHODS: A tertiary-care-center-based cross-sectional study included 40 consecutive cases with DME and 20 healthy controls in the age group of 40-65 years. All the study subjects underwent spectral-domain optical coherence tomography (SD-OCT) for cross-sectional imaging of the retina. The EZ was defined as a hyperreflective band below the external limiting membrane. The disruption of EZ was graded as intact EZ and disrupted EZ. Serum AGEs were assessed by assay of Nε-carboxymethyl-lysine (Nε-CML) using the standard protocol. Data were analyzed statistically. RESULTS: Subfoveal EZ disruption was noted in 80% (32/40) of the cases of DME. In the cases without EZ disruption, visual acuity (LogMAR VA) was 0.60 ± 0.52, whereas in cases with EZ disruption, LogMAR VA was 0.96 ± 0.56 (P < 0.001). In the cases without EZ disruption, Nε-CML was 94.31 ± 57 ng/mL, whereas in cases with EZ disruption Nε-CML was 120.64 ± 71.98 ng/mL (P < 0.001). CONCLUSION: In DME, increased levels of AGEs are significantly associated with EZ disruption on SD-OCT.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Adulto , Anciano , Estudios Transversales , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Productos Finales de Glicación Avanzada , Humanos , Edema Macular/diagnóstico , Edema Macular/etiología , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Tomografía de Coherencia Óptica
11.
Nat Commun ; 12(1): 3028, 2021 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-34021132

RESUMEN

Gene mutations causing cytoplasmic mislocalization of the RNA-binding protein FUS lead to severe forms of amyotrophic lateral sclerosis (ALS). Cytoplasmic accumulation of FUS is also observed in other diseases, with unknown consequences. Here, we show that cytoplasmic mislocalization of FUS drives behavioral abnormalities in knock-in mice, including locomotor hyperactivity and alterations in social interactions, in the absence of widespread neuronal loss. Mechanistically, we identified a progressive increase in neuronal activity in the frontal cortex of Fus knock-in mice in vivo, associated with altered synaptic gene expression. Synaptic ultrastructural and morphological defects were more pronounced in inhibitory than excitatory synapses and associated with increased synaptosomal levels of FUS and its RNA targets. Thus, cytoplasmic FUS triggers synaptic deficits, which is leading to increased neuronal activity in frontal cortex and causing related behavioral phenotypes. These results indicate that FUS mislocalization may trigger deleterious phenotypes beyond motor neuron impairment in ALS, likely relevant also for other neurodegenerative diseases characterized by FUS mislocalization.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Citoplasma/metabolismo , Proteína FUS de Unión a ARN/genética , Proteína FUS de Unión a ARN/metabolismo , Sinapsis/metabolismo , Esclerosis Amiotrófica Lateral/genética , Animales , Femenino , Expresión Génica , Técnicas de Sustitución del Gen , Masculino , Ratones , Ratones Endogámicos C57BL , Neuronas Motoras/metabolismo , Mutación , Fenotipo , Transmisión Sináptica/fisiología
12.
Bioorg Med Chem ; 18(5): 1875-81, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20149663

RESUMEN

3,5-Diaryl pyrazolines analogs were synthesized and evaluated for their monoamine oxidase (MAO) inhibitory activity. The compounds were found reversible and selective towards MAO-A with selectivity index in the magnitude of 10(3)-10(5). The docking studies were carried out to gain further structural insights of the binding mode and possible interactions with the active site of MAO-A. Interestingly, the theoretical (K(i)) values obtained by molecular docking studies were in congruence with their experimental (K(i)) values.


Asunto(s)
Inhibidores de la Monoaminooxidasa/síntesis química , Monoaminooxidasa/química , Pirazoles/química , Animales , Sitios de Unión , Simulación por Computador , Cinética , Monoaminooxidasa/metabolismo , Inhibidores de la Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/farmacología , Pirazoles/síntesis química , Pirazoles/farmacología , Ratas , Relación Estructura-Actividad
13.
Bioorg Med Chem Lett ; 19(19): 5582-5, 2009 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-19716699

RESUMEN

GSK-3beta, one of the vital enzymes responsible for various phosphorylation catalysis. Induced fit mechanism and the presence of conserved water molecule(s) in the active site poses complexity during the process of virtual screening. The present investigation reveals the practical strategy to handle the induced fit mechanism of GSK-3beta though flexible docking protocol. This protocol provides an enrichment of 70% in top 1% of the dataset with a rank correlation of >0.9 and found better in comparison to earlier reported protocols.


Asunto(s)
Glucógeno Sintasa Quinasa 3/química , Dominio Catalítico , Simulación por Computador , Diseño de Fármacos , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Estructura Terciaria de Proteína
14.
Bioorg Med Chem Lett ; 18(23): 6248-50, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-18976907

RESUMEN

Ribonucleotide reductase (RR) is an important therapeutic target for anticancer drugs. The structure of human RR features a 1:1 complex of two homodimeric subunits, hRRM1 and hRRM2. Prokaryotically expressed and highly purified recombinant human RR subunits, hRRM1 and hRRM2, were used for holoenzyme-based [(3)H]CDP reduction in vitro assay. Ten new thiosemicarbazones (7-16) were synthesized and screened for their RR inhibitory activity. Two thiosemicarbazones derived from p-hydroxy benzaldehyde (9 and 10) were found to be active but less potent than the standard, Hydroxyurea (HU). Guided by the activity of compounds 9 and 10, 11 new thiosemicarbazones (17-27) derived from p-hydroxy benzaldehyde were prepared and screened for their RR inhibitory activity. All the 11 compounds were more potent than HU.


Asunto(s)
Ribonucleótido Reductasas/antagonistas & inhibidores , Ribonucleótido Reductasas/química , Tiosemicarbazonas/síntesis química , Tiosemicarbazonas/farmacología , Humanos , Hidroxiurea/farmacología , Estructura Molecular , Oxidación-Reducción , Subunidades de Proteína/química , Tiosemicarbazonas/química
15.
Indian J Ophthalmol ; 71(5): 2294-2295, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37202980
16.
Sci Rep ; 7: 42755, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28209997

RESUMEN

MicroRNA (miR)-132 brain-to-body messages suppress inflammation by targeting acetylcholinesterase (AChE), but the target specificity of 3'-AChE splice variants and the signaling pathways involved remain unknown. Using surface plasmon resonance (SPR), we identified preferential miR-132 targeting of soluble AChE-R over synaptic-bound AChE-S, potentiating miR-132-mediated brain and body cholinergic suppression of pro-inflammatory cytokines. Inversely, bacterial lipopolysaccharide (LPS) reduced multiple miR-132 targets, suppressed AChE-S more than AChE-R and elevated inflammatory hallmarks. Furthermore, blockade of peripheral miR-132 by chemically protected AM132 antisense oligonucleotide elevated muscle AChE-R 10-fold over AChE-S, and cortical miRNA-sequencing demonstrated inverse brain changes by AM132 and LPS in immune-related miRs and neurotransmission and cholinergic signaling pathways. In neuromuscular junctions, AM132 co-elevated the nicotinic acetylcholine receptor and AChE, re-balancing neurotransmission and reaching mild muscle incoordination. Our findings demonstrate preferential miR-132-induced modulation of AChE-R which ignites bidirectional brain and body anti-inflammatory regulation, underscoring splice-variant miR-132 specificity as a new complexity level in inflammatory surveillance.


Asunto(s)
Acetilcolinesterasa/metabolismo , Corteza Cerebral/metabolismo , Citocinas/metabolismo , Acetilcolinesterasa/genética , Animales , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/patología , Citocinas/genética , Inflamación , Isoenzimas , Lipopolisacáridos/toxicidad , Masculino , Ratones , Ratones Endogámicos BALB C , MicroARNs/genética , MicroARNs/metabolismo , Receptores Nicotínicos/metabolismo
17.
BMJ Case Rep ; 20162016 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-27402655

RESUMEN

To study the retinal structural alterations and surface topography of retinal pigment epithelium (RPE) immediately following laser photocoagulation up to day 7. Cross-sectional retinal imaging and RPE segmentation maps on spectral domain optical coherence tomography were obtained immediately at hour 1, day 1, day 4 and day 7 following 532 nm neodymium:YAG laser photocoagulation in a 56-year-old male patient for branch retinal vein occlusion. Immediately postlaser, loss of reflectivity of all the retinal layers was observed. At hour 1, hyper-reflectivity of outer retinal layers was observed with increase in hyporeflective spaces by day 1. Immediately postlaser, pitting of the RPE was observed on surface topography which regressed at day 1. On day 4, smooth RPE surface topography was observed with the occurrence of small elevated areas on day 7. The present report provides an insight into the in vivo changes in the retinal structure and RPE surface topography after laser photocoagulation.


Asunto(s)
Imagenología Tridimensional/métodos , Coagulación con Láser , Láseres de Estado Sólido/uso terapéutico , Retina/diagnóstico por imagen , Oclusión de la Vena Retiniana/cirugía , Tomografía de Coherencia Óptica/métodos , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Retina/cirugía , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Resultado del Tratamiento
18.
Neurochem Int ; 93: 113-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26796202

RESUMEN

Naturally, occurring compounds with MAO inhibitory property may provide promising lead molecules against neurodegenerative disorders. We report MAO inhibitory activity of a naturally occurring coumarin (validated chemical scaffold as MAO inhibitors), scopoletin. It selectively (and reversibly) inhibits human (Ki = 20.7 µM) and mouse (Ki = 22 µM) MAO-B, ∼3.5 times more selective towards MAO-B than MAO-A. Docking studies revealed its molecular recognition and explained the selectivity mechanism towards MAO isoforms. Scopoletin occupied the hydrophobic aromatic pockets showing favorable interactions for MAO-B; experimental Ki agreed with the predicted Ki. In vivo, scopoletin (80 mg/kg, i.p.) treatment significantly increases dopamine level and decreases its metabolite DOPAC in striatum. Overall, scopoletin is a partially selective MAO-B inhibitor that increases brain dopamine level.


Asunto(s)
Aminas/metabolismo , Encéfalo/efectos de los fármacos , Monoaminooxidasa/efectos de los fármacos , Escopoletina/farmacología , Animales , Encéfalo/metabolismo , Masculino , Ratones , Simulación del Acoplamiento Molecular
19.
J Diabetes Complications ; 30(3): 511-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26782022

RESUMEN

PURPOSE: To correlate serum levels of N-epsilon-carboxy methyl lysine (N(ε)-CML) with severity of retinopathy, in vivo macular edema and disruption of external limiting membrane (ELM) and photoreceptor ellipsoid zone in type 2 diabetes mellitus (DM). METHODS: Consecutive cases of type 2 DM [diabetes mellitus with no retinopathy (No DR) (n=20); non- proliferative diabetic retinopathy (NPDR) with diabetic macular edema (n=20); proliferative diabetic retinopathy with diabetic macular edema (PDR) (n=20)] and healthy controls (n=20) between the ages of 40 and 65 years were included (power of study=93.8%). In vivo histology of retinal layers was assessed using spectral domain optical coherence tomography. Every study subject underwent macular thickness analysis using the macular cube 512×128 feature. Disruption of ELM and photoreceptor ellipsoid zone was graded: grade 0, no disruption of ELM and ellipsoid zone; grade 1, ELM disrupted and ellipsoid zone intact; grade 2, both ELM and ellipsoid zone disrupted. Data were statistically analyzed. RESULTS: The mean levels of N(ε)-CML were 31.34±21.23 ng/ml, 73.88±35.01 ng/ml, 91.21±66.65 ng/ml, and 132.08±84.07 ng/ml in control, No DR, NPDR and PDR respectively. N(ε)-CML level was significantly different between the study groups (control, No DR, NPDR and PDR) (p<0.001). Mean logMAR visual acuity decreased with increased levels of N(ε)-CML (p<0.001). The association of N(Ɛ)CML with the grades of disruption was found to be statistically significant (F value=18.48, p<0.001). Univariate analysis was done with N(Ɛ)-CML as a dependent variable. The values of N(Ɛ)-CML were normalized (log10) and were subjected to univariate analysis with fasting blood glucose level, glycosylated hemoglobin, central subfield macular thickness and cube average thickness among the diseased groups (NPDR and PDR) that act as confounders. It was found that none of the variables had significant effect on N(Ɛ)-CML (fasting blood glucose p=0.12, HBA1c p=0.65, central subfield macular thickness p=0.13, cube average thickness p=0.19). N(Ɛ)-CML tends to be a significant and important predictor of grade of ELM and ellipsoid zone disruption in diabetic retinopathy. CONCLUSIONS: Increased N(ε)-CML levels are associated with increased severity of diabetic retinopathy, macular edema and structural changes in macula that is ELM and ellipsoid zone disruption, which serves as a prognosticator of visual outcome.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/sangre , Lisina/análogos & derivados , Adulto , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/sangre , Retinopatía Diabética/patología , Femenino , Humanos , Lisina/sangre , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
20.
Front Mol Neurosci ; 9: 19, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27013966

RESUMEN

Neuro-inflammation, one of the pathogenic causes of neurodegenerative diseases, is regulated through the cholinergic anti-inflammatory pathway via the α7 nicotinic acetylcholine receptor (α7 nAChR). We previously showed that either bacterial lipopolysaccharide (LPS) or immunization with the α7(1-208) nAChR fragment decrease α7 nAChRs density in the mouse brain, exacerbating chronic inflammation, beta-amyloid accumulation and episodic memory decline, which mimic the early stages of Alzheimer's disease (AD). To study the molecular mechanisms underlying the LPS and antibody effects in the brain, we employed an in vivo model of acute LPS-induced inflammation and an in vitro model of cultured glioblastoma U373 cells. Here, we report that LPS challenge decreased the levels of α7 nAChR RNA and protein and of acetylcholinesterase (AChE) RNA and activity in distinct mouse brain regions, sensitized brain mitochondria to the apoptogenic effect of Ca(2+) and modified brain microRNA profiles, including the cholinergic-regulatory CholinomiRs-132/212, in favor of anti-inflammatory and pro-apoptotic ones. Adding α7(1-208)-specific antibodies to the LPS challenge prevented elevation of both the anti-inflammatory and pro-apoptotic miRNAs while supporting the resistance of brain mitochondria to Ca(2+) and maintaining α7 nAChR/AChE decreases. In U373 cells, α7-specific antibodies and LPS both stimulated interleukin-6 production through the p38/Src-dependent pathway. Our findings demonstrate that acute LPS-induced inflammation induces the cholinergic anti-inflammatory pathway in the brain, that α7 nAChR down-regulation limits this pathway, and that α7-specific antibodies aggravate neuroinflammation by inducing the pro-inflammatory interleukin-6 and dampening anti-inflammatory miRNAs; however, these antibodies may protect brain mitochondria and decrease the levels of pro-apoptotic miRNAs, preventing LPS-induced neurodegeneration.

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