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OBJECTIVE: A hitherto undescribed phenotype of early onset muscular dystrophy associated with sensorineural hearing loss and primary ovarian insufficiency was initially identified in 2 siblings and in subsequent patients with a similar constellation of findings. The goal of this study was to understand the genetic and molecular etiology of this condition. METHODS: We applied whole exome sequencing (WES) superimposed on shared haplotype regions to identify the initial biallelic variants in GGPS1 followed by GGPS1 Sanger sequencing or WES in 5 additional families with the same phenotype. Molecular modeling, biochemical analysis, laser membrane injury assay, and the generation of a Y259C knock-in mouse were done. RESULTS: A total of 11 patients in 6 families carrying 5 different biallelic pathogenic variants in specific domains of GGPS1 were identified. GGPS1 encodes geranylgeranyl diphosphate synthase in the mevalonate/isoprenoid pathway, which catalyzes the synthesis of geranylgeranyl pyrophosphate, the lipid precursor of geranylgeranylated proteins including small guanosine triphosphatases. In addition to proximal weakness, all but one patient presented with congenital sensorineural hearing loss, and all postpubertal females had primary ovarian insufficiency. Muscle histology was dystrophic, with ultrastructural evidence of autophagic material and large mitochondria in the most severe cases. There was delayed membrane healing after laser injury in patient-derived myogenic cells, and a knock-in mouse of one of the mutations (Y259C) resulted in prenatal lethality. INTERPRETATION: The identification of specific GGPS1 mutations defines the cause of a unique form of muscular dystrophy with hearing loss and ovarian insufficiency and points to a novel pathway for this clinical constellation. ANN NEUROL 2020;88:332-347.
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Dimetilaliltranstransferasa/genética , Farnesiltransferasa/genética , Geraniltranstransferasa/genética , Pérdida Auditiva/genética , Distrofias Musculares/genética , Mutación/genética , Insuficiencia Ovárica Primaria/genética , Adolescente , Adulto , Animales , Femenino , Técnicas de Sustitución del Gen/métodos , Pérdida Auditiva/diagnóstico por imagen , Humanos , Masculino , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Distrofias Musculares/diagnóstico por imagen , Linaje , Insuficiencia Ovárica Primaria/diagnóstico por imagen , Estructura Secundaria de Proteína , Análisis de Secuencia de ADN/métodos , Secuenciación del Exoma/métodos , Adulto JovenRESUMEN
Kessler et al. in this current issue have attempted to discern biomarker(s) for spinal muscular atrophy (SMA) by assessing alterations in cerebrospinal fluid (CSF) proteomics profile. Recently, antisense oligonucleotide (nusinersen) therapy is shown to mitigate pathologies and provide behavioral improvements in patients. This Editorial highlights the study by Kessler et al on the proteomics of CSF from adult and young patients prior to, and 10 months after nusinersen intrathecal therapy. Although the study by Kessler et al. suffers from small sample size and mixed results that deterred a strong conclusion, yet is a strong case-control study that is contemporary and important to the patients, clinicians and care-takers alike. Since identifying biomarker and characterizing the pathology in SMA are imminent necessity to advance this promising therapy, the high-throughput CSF proteomics data prior and after nusinersen therapy provide possible biomarkers that may help in identification of positive responders, the disease course, efficacy of treatment, and more accurate prognosis.
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Atrofia Muscular Espinal/líquido cefalorraquídeo , Atrofia Muscular Espinal/tratamiento farmacológico , Oligonucleótidos/uso terapéutico , Proteómica/métodos , Biomarcadores/líquido cefalorraquídeo , Humanos , Atrofia Muscular Espinal/genética , Proteómica/tendenciasRESUMEN
Infantile neuronal ceroid lipofuscinosis (INCL) is a devastating neurodegenerative lysosomal storage disease (LSD) caused by inactivating mutations in the CLN1 gene. CLN1 encodes palmitoyl-protein thioesterase-1 (PPT1), a lysosomal enzyme that catalyzes the deacylation of S-palmitoylated proteins to facilitate their degradation and clearance by lysosomal hydrolases. Despite the discovery more than two decades ago that CLN1 mutations causing PPT1-deficiency underlies INCL, the precise molecular mechanism(s) of pathogenesis has remained elusive. Here, we report that autophagy is dysregulated in Cln1-/- mice, which mimic INCL and in postmortem brain tissues as well as cultured fibroblasts from INCL patients. Moreover, Rab7, a small GTPase, critical for autophagosome-lysosome fusion, requires S-palmitoylation for trafficking to the late endosomal/lysosomal membrane where it interacts with Rab-interacting lysosomal protein (RILP), essential for autophagosome-lysosome fusion. Notably, PPT1-deficiency in Cln1-/- mice, dysregulated Rab7-RILP interaction and preventing autophagosome-lysosome fusion, which impaired degradative functions of the autolysosome leading to INCL pathogenesis. Importantly, treatment of Cln1-/- mice with a brain-penetrant, PPT1-mimetic, small molecule, N-tert (butyl)hydroxylamine (NtBuHA), ameliorated this defect. Our findings reveal a previously unrecognized role of CLN1/PPT1 in autophagy and suggest that small molecules functionally mimicking PPT1 may have therapeutic implications.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Lisosomas/enzimología , Lipofuscinosis Ceroideas Neuronales/genética , Tioléster Hidrolasas/metabolismo , Proteínas de Unión al GTP rab/metabolismo , Animales , Autofagia , Células Cultivadas , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Lipofuscinosis Ceroideas Neuronales/patología , Tioléster Hidrolasas/genética , Proteínas de Unión a GTP rab7RESUMEN
Infectious diseases caused by bacteria still pose major diagnostic challenges in spite of the availability of various molecular approaches. Irrespective of the type of infection, rapid identification of the causative pathogen with a high degree of sensitivity and specificity is essential for initiating appropriate treatment. While existing methods like PCR possess high sensitivity, they are incapable of identifying the viability status of the pathogen and those which can, like culturing, are inherently slow. To overcome these limitations, we developed a diagnostic platform based on Raman microspectroscopy, capable of detecting biochemical signatures from a single bacterium for identification as well as viability assessment. The study also establishes a decontamination protocol for handling live pathogenic bacteria which does not affect identification and viability testing, showing applicability in the analysis of sputum samples containing pathogenic mycobacterial strains. The minimal sample processing along with multivariate analysis of spectroscopic signatures provides an interface for automatic classification, allowing the prediction of unknown samples by mapping signatures onto available datasets. Also, the novelty of the current work is the demonstration of simultaneous identification and viability assessment at a single bacterial level for pathogenic bacteria. Graphical abstract.
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Bacterias/aislamiento & purificación , Infecciones Bacterianas/diagnóstico , Espectrometría Raman/métodos , Bacterias/química , Humanos , Sensibilidad y Especificidad , Factores de TiempoRESUMEN
OBJECTIVE: This study aims to detect pathogenic Escherichia coli (E. coli) bacteria using non-destructive fluorescence microscopy and micro-Raman spectroscopy. RESULTS: Raman vibrational spectroscopy provides additional information regarding biochemical changes at the cellular level. We have used two nanomaterials zinc oxide nanoparticles (ZnO-NPs) and gold nanoparticles (Au-NPs) to detect pathogenic E. coli. The scanning electron microscope (SEM) with energy dispersive X-ray (EDAX) spectroscopy exhibit surface morphology and the elemental composition of the synthesized NPs. The metal NPs are useful contrast agents due to the surface plasmon resonance (SPR) to detect the signal intensity and hence the bacterial cells. The changes due to the interaction between cells and NPs are further correlated to the change in the surface charge and stiffness of the cell surface with the help of the fluorescence microscopic assay. CONCLUSIONS: We conclude that when two E. coli strains (MTCC723 and MTCC443) and NPs are respectively mixed and kept overnight, the growth of bacteria are inhibited by ZnO-NPs due to changes in cell membrane permeability and intracellular metabolic system under fluorescence microscopy. However, SPR possessed Au-NPs result in enhanced fluorescence of both pathogens. In addition, with the help of Raman microscopy and element analysis, significant changes are observed when Au-NPs are added with the two strains as compared to ZnO-NPs due to protein, lipid and DNA/RNA induced conformational changes.
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Antibacterianos/farmacología , Escherichia coli/aislamiento & purificación , Oro/farmacología , Óxido de Zinc/farmacología , Antibacterianos/química , Permeabilidad de la Membrana Celular , Escherichia coli/efectos de los fármacos , Escherichia coli/patogenicidad , Proteínas de Escherichia coli/efectos de los fármacos , Proteínas de Escherichia coli/metabolismo , Oro/química , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Microscopía Fluorescente , Propiedades de Superficie , Óxido de Zinc/químicaRESUMEN
BACKGROUND & OBJECTIVES: Lymphatic filariasis (LF) is a neglected parasitic disease of tropics and subtropics including India. Although the disease mostly affects adults, there are evidences that LF infection is often acquired during childhood. This study assessed the filarial epidemiology as well as awareness about the disease among school children in the rural areas of Bankura district, West Bengal, India. METHODS: Night blood samples of 1193 school children were examined to detect microfilariae. They were examined clinically by a physician for filarial manifestations and inquired about their awareness on the disease. RESULTS: Microfilaria rate and disease rate among school children of the study area were assessed as 3.69% and 8.97% respectively. Only 12.74% of the school children had proper knowledge about filariasis and 72.09% had filarial patients living nearby. Among those affected children, 53.79% never received proper medical attention and 66.21% were found to be anxious about the fate of their filarial problems. School going males were found to be more affected than the females. Anxiety about the effect of the disease in girls was higher due to societal and medical ignorance among women that might develop psychological concerns. INTERPRETATION & CONCLUSION: This study suggests that, in the present study area, about 12.15% population acquired filarial infection at the stage of schooling. But effort for developing awareness about filariasis among the school children is scanty, which is presumably one of the major causes of high endemicity. To rectify the situation, knowledge about mosquito and mosquito borne diseases, including LF, should be properly incorporated in school curriculum. Control measures like anti-filarial drug administration and morbidity-management can be implemented in schools by the local governments, as it should be.
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Filariasis Linfática , Animales , Niño , Filariasis Linfática/epidemiología , Femenino , Humanos , India/epidemiología , Masculino , Microfilarias , Prevalencia , Instituciones Académicas , Wuchereria bancroftiRESUMEN
Application of antibiotics to combat bacterial diseases in fish has been criticized due to likely emergence of drug resistance. Therefore, investigation of new bioactive compounds from natural sources has been taken into account. This study was designed to purify and characterize the bioactive compound in the cell free supernatant (CFSs) of autochthonous gut bacteria (Bacillus methylotrophicus KU556164, B. amyloliquefaciens KU556165, Pseudomonas fluorescens KU556166 and B. licheniformis KU556167) isolated from rohu, Labeo rohita. CFSs were antagonistic to fish pathogenic Aeromonas spp., moderately thermo-tolerant and active in wide range of pH (5-11). Antibacterial activity of the CFSs was reduced by the action of proteases (e.g., Proteinase K and Trypsin), indicating proteinaceous nature of the bioactive compound like the bacteriocins. Three-step purification procedure resulted in recovery of 16.97%, 18.04%, 33.33% and 6.38% activity of the antimicrobial protein produced by B. methylotrophicus, B. amyloliquefaciens, P. fluorescens and B. licheniformis, respectively. Purification at each step revealed decrease in protein content with gradual increase in the specific activity of the antimicrobial protein. The purified antibacterial compound ranged between 18.2 and 25.6â¯kDa. Identification through MALDI-TOF MS/MS and database search through Mascot search engine predicted that the bactericidal compound belonged to either alkaline proteases, or, transcriptional regulator and some hypothetical proteins. Apart from potential technological application of the antibacterial compound, the present study might show promise for application of gut-associated bacteriocinogenic bacteria to control diseases in fish caused by pathogenic bacteria.
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Antibacterianos/metabolismo , Bacterias/metabolismo , Proteínas Bacterianas/metabolismo , Productos Biológicos/metabolismo , Cyprinidae/microbiología , Microbioma Gastrointestinal , Aeromonas/efectos de los fármacos , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antibiosis , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/farmacología , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Concentración de Iones de Hidrógeno , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Although the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model is the most widely used animal model for Parkinson's disease (PD), it is known that nigrostriatal pathologies do not persist in the acute MPTP mouse model. This study highlights the importance of adaptive immunity in driving persistent and progressive disease in acute MPTP-intoxicated mice. Although marked infiltration of T cells into the nigra was found on 1 d of MPTP insult, T cell infiltration decreased afterward, becoming normal on 30 d of insult. Interestingly, twice-weekly supplementation of RANTES and eotaxin, chemokines that are involved in T cell trafficking, drove continuous T cell infiltration to the nigra and incessant glial inflammation. Supplementation of RANTES and eotaxin was also associated with the induction of nigral α-synuclein pathology, persistent loss of dopaminergic neurons and striatal neurotransmitters, and continuous impairment of motor functions in MPTP-intoxicated mice. In contrast, supplementation of TNF-α and IL-1ß, widely studied proinflammatory cytokines, did not induce persistent disease in MPTP-insulted mice. Our results suggest that induction of adaptive immunity by RANTES and eotaxin could hold the key for driving persistent nigrostriatal pathologies in the MPTP mouse model, and that targeting these factors may halt disease progression in PD patients.
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Inmunidad Adaptativa , Intoxicación por MPTP/inmunología , Intoxicación por MPTP/fisiopatología , Sustancia Negra/inmunología , Enfermedad Aguda , Animales , Quimiocina CCL11/administración & dosificación , Quimiocina CCL5/administración & dosificación , Progresión de la Enfermedad , Inflamación , Interleucina-1beta/administración & dosificación , Intoxicación por MPTP/patología , Ratones , Ratones Endogámicos C57BL , Sustancia Negra/patología , Factor de Necrosis Tumoral alfa/administración & dosificaciónRESUMEN
Ionic liquids (ILs) and their aqueous solutions are emerging media for solving and manipulating biochemical molecules such as proteins. Unleashing the full potential however requires a detailed mechanistic understanding of how suitable protic and aprotic ILs behave in the presence of water in the first place. The present work aims at making an important step by performing a combined experimental and computational study of two selected ILs and their mixtures with water: the aprotic cholinium propionate ([Chl][Pro]) and the protic N-methyl-2-pyrrolidonium propionate ([NMP][Pro]). IR and Raman spectroscopy reveal stronger ion-solvent interactions in [Chl][Pro]-H2O systems compared to [NMP][Pro]-H2O mixtures. This can be explained by the tightly packed ion-pair associations in [NMP][Pro] comprising the protic -N+-H counterpart, which allows the establishment of highly directional and strong interionic hydrogen bonds. The spectral decomposition of the O-D stretching band into three sub-peaks showed that the protic [NMP][Pro] favors the self-association of water molecules. On the other hand, the predominant fraction of water-anion/cation aggregates exists in aprotic [Chl][Pro]. These hydrated systems can be envisaged using quantum-chemical calculations in the following way: H2O[Chl]+H2O[Pro]-H2O and H2O[NMP]+[Pro]-H2O, which implied preferable solvent-shared ion-pair (SIP) configurations for [Chl][Pro]-H2O systems, whereas the contact ion-pair (CIP) state prevails for the [NMP][Pro]-H2O systems. The latter holds even in the water-rich regime. In future work, these findings will be the basis for an understanding of the underlying principles that govern the interactions of ions with bio-molecules in aqueous solutions.
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Mutations of the DYSF gene leading to reduced dysferlin protein level causes limb girdle muscular dystrophy type 2B (LGMD2B). Dysferlin facilitates sarcolemmal membrane repair in healthy myofibers, thus its deficit compromises myofiber repair and leads to chronic muscle inflammation. An experimental therapeutic approach for LGMD2B is to protect damage or improve repair of myofiber sarcolemma. Here, we compared the effects of prednisolone and vamorolone (a dissociative steroid; VBP15) on dysferlin-deficient myofiber repair. Vamorolone, but not prednisolone, stabilized dysferlin-deficient muscle cell membrane and improved repair of dysferlin-deficient mouse (B6A/J) myofibers injured by focal sarcolemmal damage, eccentric contraction-induced injury or injury due to spontaneous in vivo activity. Vamorolone decreased sarcolemmal lipid mobility, increased muscle strength, and decreased late-stage myofiber loss due to adipogenic infiltration. In contrast, the conventional glucocorticoid prednisolone failed to stabilize dysferlin deficient muscle cell membrane or improve repair of dysferlinopathic patient myoblasts and mouse myofibers. Instead, prednisolone treatment increased muscle weakness and myofiber atrophy in B6A/J mice-findings that correlate with reports of prednisolone worsening symptoms of LGMD2B patients. Our findings showing improved cellular and pre-clinical efficacy of vamorolone compared to prednisolone and better safety profile of vamorolone indicates the suitability of vamorolone for clinical trials in LGMD2B.
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Disferlina/deficiencia , Distrofias Musculares/tratamiento farmacológico , Esteroides/uso terapéutico , Adolescente , Animales , Células Cultivadas , Disferlina/metabolismo , Humanos , Masculino , Ratones , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Prednisolona/uso terapéutico , Pregnadienodioles/uso terapéuticoRESUMEN
BACKGROUND: Plant derived medicines show significant contributions to mankind in treating infections of pathogenic bacteria. Recently plants are used in pharmaceutical industries for novel drug preparations because to ensure efficacy and safety as synthetic antibiotics are threatened for their multidrug resistance. The present study aimed at finding antibacterial potential of aqueous and ethanolic leaf extracts of Combretum album. METHODS: Antibacterial activity was evaluated against seven bacterial strains by determining minimum inhibitory concentration (MIC) and zone of inhibition. Diameters of the zone of inhibition were compared with standard antibiotics. Preliminary phytochemical screening was done according to standard protocol. FTIR analysis was performed to identify the general phytochemical groups of compounds in the extract. All experiments were conducted in triplicate and values were expressed as the mean ± standard deviation. One-way analysis of variance (ANOVA) and Tukey tests were performed for statistical justification. RESULTS: Maximum zones of inhibition were found in case of ethanolic extracts in the following order Bacillus licheniformis (MTCC 530) > Pseudomonas aeruginosa (MTCC 2453) > Bacillus subtilis (MTCC 441) >, Pseudomonas fluorescens (MTCC 103) > Bacillus mycoides (MTCC 7343) > Escherichia coli (MTCC 739) > Pseudomonas putida (MTCC 1654) with zone of inhibition of 27.67 ± 0.33 mm diameter in B. licheniformis (MTCC 530). Qualitatively, the ethanol extract contains flavonoids, tannins and alkaloids. The results of FTIR analysis confirmed the presence of R-CH2-OH groups, aromatics, C-N stretching amine and NH stretching secondary amine. One way ANOVA and Tukey tests statistically justify the data (p ≤ 0.05). CONCLUSIONS: All the tested leaf extracts showed promising antibacterial activity against both gram positive and gram negative bacteria. Phytochemical screening and FTIR analysis revealed the presence of tannins, alkaloids, R-CH2-OH groups, aromatics and flavonoids in ethanolic leaf extract qualitatively and these compounds could be responsible for antibacterial property of leaf extracts of C. album.
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Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/microbiología , Combretum/química , Extractos Vegetales/farmacología , Alcaloides/química , Alcaloides/farmacología , Antibacterianos/química , Bacterias/genética , Fenómenos Fisiológicos Bacterianos , Flavonoides/química , Flavonoides/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Hojas de la Planta/química , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Mesoporous carbon nitrides (MCN) with C3 N4 stoichiometry could find applications in fields ranging from catalysis, sensing, and adsorption-separation to biotechnology. The extension of the synthesis of MCN with different nitrogen contents and chemical structures promises access to a wider range of applications. Herein we prepare mesoporous C3 N5 with a combined triazole and triazine framework via a simple self-assembly of 5-amino-1H-tetrazole (5-ATTZ). We are able to hybridize these nanostructures with graphene by using graphene-mesoporous-silica hybrids as a template to tune the electronic properties. DFT calculations and spectroscopic analyses clearly demonstrate that the C3 N5 consists of 1â triazole and 2â triazine moieties. The triazole-based mesoporous C3 N5 and its graphene hybrids are found to be highly active for oxygen reduction reaction (ORR) with a higher diffusion-limiting current density and a decreased overpotential than those of bulk g-C3 N4 .
RESUMEN
Highly ordered mesoporous C60 with a well-ordered porous structure and a high crystallinity is prepared through the nanohard templating method using a saturated solution of C60 in 1-chloronaphthalene (51â mg mL-1 ) as a C60 precursor and SBA-15 as a hard template. The high solubility of C60 in 1-chloronaphthalene helps not only to encapsulate a huge amount of the C60 into the mesopores of the template but also supports the oligomerization of C60 and the formation of crystalline walls made of C60 . The obtained mesoporous C60 exhibits a rod-shaped morphology, a high specific surface area (680â m2 g-1 ), tuneable pores, and a highly crystalline wall structure. This exciting ordered mesoporous C60 offers high supercapacitive performance and a high selectivity to H2 O2 production and methanol tolerance for ORR. This simple strategy could be adopted to make a series of mesoporous fullerenes with different structures and carbon atoms as a new class of energy materials.
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Parkinson disease (PD) is second only to Alzheimer disease as the most common human neurodegenerative disorder. Despite intense investigation, no interdictive therapy is available for PD. Recent studies indicate that both innate and adaptive immune processes are active in PD. Accordingly, we found a rapid increase in RANTES (regulated on activation normal T cell expressed and secreted) and eotaxin, chemokines that are involved in T cell trafficking, in vivo in the substantia nigra pars compacta and the serum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated mice. RANTES and eotaxin were also up-regulated in the substantia nigra pars compacta of post-mortem PD brains as compared with age-matched controls. Therefore, we investigated whether neutralization of RANTES and eotaxin could protect against nigrostriatal degeneration in MPTP-intoxicated mice. Interestingly, after peripheral administration, functional blocking antibodies against RANTES and eotaxin reduced the infiltration of CD4(+) and CD8(+) T cells into the nigra, attenuated nigral expression of proinflammatory molecules, and suppressed nigral activation of glial cells. These findings paralleled dopaminergic neuronal protection, normalized striatal neurotransmitters, and improved motor functions in MPTP-intoxicated mice. Therefore, we conclude that attenuation of the chemokine-dependent adaptive immune response may be of therapeutic benefit for PD patients.
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Quimiocina CCL11/antagonistas & inhibidores , Quimiocina CCL5/antagonistas & inhibidores , Neuronas Dopaminérgicas/inmunología , Trastornos Parkinsonianos/terapia , Inmunidad Adaptativa , Anciano , Anciano de 80 o más Años , Animales , Anticuerpos Bloqueadores/administración & dosificación , Encéfalo/inmunología , Encéfalo/patología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Quimiocina CCL11/biosíntesis , Quimiocina CCL11/inmunología , Quimiocina CCL5/biosíntesis , Quimiocina CCL5/inmunología , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/patología , Humanos , Terapia de Inmunosupresión , Mediadores de Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/inmunología , Microglía/patología , Persona de Mediana Edad , Trastornos Parkinsonianos/inmunología , Trastornos Parkinsonianos/patología , Sustancia Negra/inmunología , Sustancia Negra/patologíaRESUMEN
Neurodegeneration is a devastating manifestation in the majority of >50 lysosomal storage disorders (LSDs). Neuronal ceroid lipofuscinoses (NCLs) are the most common childhood neurodegenerative LSDs. Mutations in 13 different genes (called CLNs) underlie various types of NCLs, of which the infantile NCL (INCL) and congenital NCL (CNCL) are the most lethal. Although inactivating mutations in the CLN1 gene encoding palmitoyl-protein thioesterase-1 (PPT1) cause INCL, those in the CLN10 gene encoding cathepsin D (CD) underlie CNCL. PPT1 is a lysosomal thioesterase that cleaves the thioester linkage in S-acylated proteins required for their degradation by lysosomal hydrolases like CD. Thus, PPT1 deficiency causes lysosomal accumulation of these lipidated proteins (major constituents of ceroid) leading to INCL. We sought to determine whether there is a common pathogenic link between INCL and CNCL. Using biochemical, histological and confocal microscopic analyses of brain tissues and cells from Cln1(-/-) mice that mimic INCL, we uncovered that Cln10/CD is overexpressed. Although synthesized in the endoplasmic reticulum, the CD-precursor protein (pro-CD) is transported through endosome to the lysosome where it is proteolytically processed to enzymatically active-CD. We found that despite Cln10 overexpression, the maturation of pro-CD to enzymatically active-CD in lysosome was disrupted. This defect impaired lysosomal degradative function causing accumulation of undegraded cargo in lysosome leading to INCL. Notably, treatment of intact Cln1(-/-) mice as well as cultured brain cells derived from these animals with a thioesterase-mimetic small molecule, N-tert-butyl-hydroxylamine, ameliorated the CD-processing defect. Our findings are significant in that they define a pathway in which Cln1 mutations disrupt the maturation of a major degradative enzyme in lysosome contributing to neuropathology in INCL and suggest that lysosomal CD deficiency is a common pathogenic link between INCL and CNCL.
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Encéfalo/metabolismo , Catepsina D/metabolismo , Lipofuscinosis Ceroideas Neuronales/patología , Tioléster Hidrolasas/genética , Animales , Encéfalo/patología , Catepsina D/deficiencia , Niño , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Humanos , Hidroxilaminas/administración & dosificación , Hidroxilaminas/uso terapéutico , Lisosomas/metabolismo , Ratones , Mutación , Lipofuscinosis Ceroideas Neuronales/tratamiento farmacológico , Lipofuscinosis Ceroideas Neuronales/genéticaRESUMEN
To identify and characterize glycation, induced modifications of DNA are crucial toward understanding their functional significance due to their significant role in the long term control of aging and age-related diseases. In this study, we present the ability of Raman microspectroscopy as a novel analytical technique for a rapid and reliable identification of glycated DNA in a reagent-free manner. We have demonstrated that this technique has potential to provide very small conformational modifications. The combination of principal component analysis (PCA) and two-dimensional (2D) correlation spectroscopy has assisted us to explore in vitro DNA-glycation and provide more insights into the dynamics of the DNA-glycation process in an easier fashion. PCA analysis of Raman spectra shows a clear discrimination between native and glycated DNA samples. On the other hand, 2D correlation Raman analysis provides sequential order of the mechanism of the DNA-glycation process, and most likely, it occurs in the following sequence: Structural modifications of individual nucleobases (G > A > C) â DNA backbone modifications â partial transition of DNA conformations (A to B form). Our observations clearly suggest that the structure of DNA is altered, i.e., a partial transition of DNA backbone conformation from A to B form when glycated, but does not induce any final transition in DNA double helix conformation, and eventually, DNA presents in an intermediate A-B form, more toward the B form.
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ADN/química , Indicadores y Reactivos/química , Ribosa/química , Espectrometría Raman/métodos , Animales , Bovinos , Glicosilación , Técnicas In Vitro , Conformación de Ácido Nucleico , Espectrofotometría UltravioletaRESUMEN
Acyl-protein thioesterase-1 (APT1) and APT2 are cytosolic enzymes that catalyze depalmitoylation of membrane-anchored, palmitoylated H-Ras and growth-associated protein-43 (GAP-43), respectively. However, the mechanism(s) of cytosol-membrane shuttling of APT1 and APT2, required for depalmitoylating their substrates H-Ras and GAP-43, respectively, remained largely unknown. Here, we report that both APT1 and APT2 undergo palmitoylation on Cys-2. Moreover, blocking palmitoylation adversely affects membrane localization of both APT1 and APT2 and that of their substrates. We also demonstrate that APT1 not only catalyzes its own depalmitoylation but also that of APT2 promoting dynamic palmitoylation (palmitoylation-depalmitoylation) of both thioesterases. Furthermore, shRNA suppression of APT1 expression or inhibition of its thioesterase activity by palmostatin B markedly increased membrane localization of APT2, and shRNA suppression of APT2 had virtually no effect on membrane localization of APT1. In addition, mutagenesis of the active site Ser residue to Ala (S119A), which renders catalytic inactivation of APT1, also increased its membrane localization. Taken together, our findings provide insight into a novel mechanism by which dynamic palmitoylation links cytosol-membrane trafficking of APT1 and APT2 with that of their substrates, facilitating steady-state membrane localization and function of both.
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Citosol/metabolismo , Proteína GAP-43/metabolismo , Tioléster Hidrolasas/metabolismo , Proteínas ras/metabolismo , Animales , Astrocitos/citología , Dominio Catalítico , Membrana Celular/metabolismo , Células Cultivadas , Humanos , Ratones , Microscopía Confocal , Mutagénesis , Mutación , Células 3T3 NIH , Neuronas/metabolismo , Ácido Palmítico/química , Ácido Palmítico/metabolismo , Unión Proteica , Proto-Oncogenes Mas , Fracciones Subcelulares/metabolismo , TransfecciónRESUMEN
Disruption of the blood-brain barrier (BBB) is a serious complication frequently encountered in neurodegenerative disorders. Infantile neuronal ceroid lipofuscinosis (INCL) is a devastating childhood neurodegenerative lysosomal storage disorder caused by palmitoyl-protein thioesterase-1 (PPT1) deficiency. It remains unclear whether BBB is disrupted in INCL and if so, what might be the molecular mechanism(s) of this complication. We previously reported that the Ppt1-knockout (Ppt1-KO) mice that mimic INCL manifest high levels of oxidative stress and neuroinflammation. Recently, it has been reported that CD4(+) T-helper 17 (T(H)17) lymphocytes may mediate BBB disruption and neuroinflammation, although the precise molecular mechanism(s) remain unclear. We sought to determine: (i) whether the BBB is disrupted in Ppt1-KO mice, (ii) if so, do T(H)17-lymphocytes underlie this complication, and (iii) how might T(H)17 lymphocytes breach the BBB. Here, we report that the BBB is disrupted in Ppt1-KO mice and that T(H)17 lymphocytes producing IL-17A mediate disruption of the BBB by stimulating production of matrix metalloproteinases (MMPs), which degrade the tight junction proteins essential for maintaining BBB integrity. Importantly, dietary supplementation of resveratrol (RSV), a naturally occurring antioxidant/anti-inflammatory polyphenol, markedly reduced the levels of T(H)17 cells, IL-17A and MMPs, and elevated the levels of tight junction proteins, which improved the BBB integrity in Ppt1-KO mice. Intriguingly, we found that RSV suppressed the differentiation of CD4(+) T lymphocytes to IL-17A-positive T(H)17 cells. Our findings uncover a mechanism by which T(H)17 lymphocytes mediate BBB disruption and suggest that small molecules such as RSV that suppress T(H)17 differentiation are therapeutic targets for neurodegenerative disorders such as INCL.
Asunto(s)
Barrera Hematoencefálica/metabolismo , Inhibidores Enzimáticos/farmacología , Ratones , Lipofuscinosis Ceroideas Neuronales/metabolismo , Estilbenos/farmacología , Tioléster Hidrolasas/genética , Animales , Encéfalo/metabolismo , Encéfalo/patología , Modelos Animales de Enfermedad , Ratones Noqueados , Lipofuscinosis Ceroideas Neuronales/enzimología , Resveratrol , Tioléster Hidrolasas/metabolismoRESUMEN
BACKGROUND & OBJECTIVES: Indiscriminate use of synthetic pesticides has created serious problem for the aquatic flora and fauna, and also resulted in appearance of pesticide resistance in vector population. This study was designed to evaluate the biocontrol efficacy of aqueous and solvent extracts of mature leaves of Solanum nigrum L., against fresh water snail Lymnaea acuminata f. rufescens (Gray) (an intermediate host of parasites causing fasciolopsiasis) and larvae of Culex vishnui group (Reuben) (vector of Japanese encephalitis). METHODS: Aqueous and solvent extracts of fresh, mature, green/shed dried leaves of S. nigrum were tested against adult L. acuminata and larvae of Cx. vishnui group. The lethal concentration was determined and the appropriate lethal concentration at 24 h of benzene extract was also studied on non target organisms such as Daphnia sp, Diplonychus annulatum and Chironomus circumdatus. A qualitative phytochemical analysis was carried out in search of active ingredient and the chemical nature of the active substance was also evaluated by infrared (IR) analysis. RESULTS: In a 72 h bioassay experiment with the aqueous extract, the highest mortality was recorded in 0.5 and 3 per cent extract against larvae of Cx. vishnui group and L. acuminata, respectivela. In the benzene solvent extract, the maximum mortality was recorded at a concentration of 150 ppm against L. acuminata and at 50 ppm against larvae of Cx. vishnui group with LC 50 values of 55.45 and 11.59 ppm, respectively at 72 h. The log probit analysis (95% confidence level) recorded lowest value at 72 h of exposure. Qualitative phytochemical analysis reported the presence of some biochemical compounds, such as saponin, flavonoids, steroid and tannin. Among these, the toxic compound was detected by IR analysis having Rf=0.87 (showed 66.70% and 76.70% mortality of L. acuminata and larvae of Cx. vishnui group, respectively). IR analysis provided preliminary information about the aliphatic amide nature of the active ingredient. INTERPRETATION & CONCLUSIONS: The study results provide considerable scope in exploiting local indigenous plant resources for molluscicidal and mosquito larvicidal activities.
Asunto(s)
Culex/efectos de los fármacos , Lymnaea/efectos de los fármacos , Control Biológico de Vectores/métodos , Extractos Vegetales/toxicidad , Hojas de la Planta/química , Solanum nigrum/química , Amidas/química , Amidas/toxicidad , Animales , Benceno , Relación Dosis-Respuesta a Droga , Larva/efectos de los fármacos , Extractos Vegetales/análisis , AguaRESUMEN
BACKGROUND & OBJECTIVES: Mosquitoes transmit serious human health diseases, causing millions of deaths every year. Plants may be sources of alternative mosquito control agents. The present study was carried out to assess the role of larvicidal activities of the crude extracts of four plants viz. Alternanthera sessilis L. (Amaranthaceae), Trema orientalis L. (Cannabaceae), Gardenia carinata Smith. (Rubiaceae) and Ruellia tuberosa L. (Acanthaceae) against Culex quinquefasciatus Say in laboratory bioassay. METHODS: Selective concentrations (0.5, 1 and 1.5%) of crude extract of all four plant leaves were tested against I st to IV th instar larvae of Cx. quinquefasciatus. Log probit analysis (at 95% confidence level) revealed the LC50 values. Preliminary qualitative phytochemical analyses of crude extracts were also done. The lethal concentrations (%) of crude extracts at 24 h against III rd instar larvae were also studied on non-target organisms. RESULT: In a 72 h bioassay experiment with crude extract, the highest mortality was recorded in 1.5 per cent extract. A. sessilis showed the highest mortality (76.7%) at 1.5 per cent crude extract against II nd instar larvae having LC50 value of 0.35 per cent, followed by R. tuberosa (LC50 = 1.84%), G. carinata (LC50 = 2.11) and T. orientalis (LC50 = 2.95%). The regression equation showed a dose-dependent mortality, as the rate of mortality (Y) was positively correlated with the concentration (X). Phytochemical analysis of the crude extract showed the presence of many bioactive phytochemicals such as steroids, alkaloids, terpenes, saponins, etc. No changes in the swimming behaviour and survivality of non-target organism were noticed at the studied concentrations. INTERPRETATION & CONCLUSIONS: Crude extract of the four selected plants showed larvicidal activity against Cx. quinquefasciatus. The extracts at the studied concentrations did not produce any harmful effect on non-target organisms.