RESUMEN
Identification of genetic mutations in Parkinson's disease (PD) promulgates the genetic nature of disease susceptibility. Resilience-associated genes being unknown till date, the normal genetic makeup of an individual may be determinative too. Our earlier studies comparing the substantia nigra (SN) and striatum of C57BL/6J, CD-1 mice, and their F1-crossbreds demonstrated the neuroprotective role of admixing against the neurotoxin MPTP. Furthermore, the differences in levels of mitochondrial fission/fusion proteins in the SN of parent strains imply effects on mitochondrial biogenesis. Our present investigations suggest that the baseline levels of apoptotic factors Bcl-2, Bax, and AIF differ across the three strains and are differentially altered in SN following MPTP administration. The reduction in complex-I levels exclusively in MPTP-injected C57BL/6J reiterates mitochondrial involvement in PD pathogenesis. The MPTP-induced increase in complex-IV, in the nigra of both parent strains, may be compensatory in nature. The ultrastructural evaluation showed fairly preserved mitochondria in the dopaminergic neurons of CD-1 and F1-crossbreds. However, in CD-1, the endoplasmic reticulum demonstrated distinct luminal enlargement, bordering onto ballooning, suggesting proteinopathy as a possible initial trigger.The increase in α-synuclein in the pars reticulata of crossbreds suggests a supportive role for this output nucleus in compensating for the lost function of pars compacta. Alternatively, since α-synuclein over-expression occurs in different brain regions in PD, the α-synuclein increase here may suggest a similar pathogenic outcome. Further understanding is required to resolve this biological contraption. Nevertheless, admixing reduces the risk to MPTP by favoring anti-apoptotic consequences. Similar neuroprotection may be envisaged in the admixed populace of Anglo-Indians.
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Intoxicación por MPTP , Enfermedad de Parkinson , Animales , Ratones , Neurotoxinas/metabolismo , alfa-Sinucleína/metabolismo , Ratones Endogámicos C57BL , Sustancia Negra/patología , Enfermedad de Parkinson/patología , Neuronas Dopaminérgicas/metabolismo , Mitocondrias/metabolismo , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Intoxicación por MPTP/metabolismoRESUMEN
Rabies is a fatal encephalitis caused by the Rabies lyssavirus (RABV). The presence of minimal neuropathological changes observed in rabies indicates that neuronal dysfunction, rather than neuronal death contributes to the fatal outcome. The role of mitochondrial changes has been suggested as a possible mechanism for neuronal dysfunction in rabies. However, these findings are mostly based on studies that have employed experimental models and laboratory-adapted virus. Studies on brain tissues from naturally infected human and animal hosts are lacking. The current study investigated the role of mitochondrial changes in rabies by morphological, biochemical and proteomic analysis of RABV-infected human and canine brains. Morphological analysis showed minimal inflammation with preserved neuronal and disrupted mitochondrial structure in both human and canine brains. Proteomic analysis revealed involvement of mitochondrial processes (oxidative phosphorylation, cristae formation, homeostasis and transport), synaptic proteins and autophagic pathways, with over-expression of subunits of mitochondrial respiratory complexes. Consistent with these findings, human and canine brains displayed elevated activities of complexes I (p < 0.05), IV (p < 0.05) and V (p < 0.05). However, this did not result in elevated ATP production (p < 0.0001), probably due to lowered mitochondrial membrane potential as noted in RABV-infected cells in culture. These could lead to mitochondrial dysfunction and mitophagy as indicated by expression of FKBP8 (p < 0.05) and PINK1 (p < 0.001)/PARKIN (p > 0.05) and ensuing autophagy, as shown by the status of LCIII (p < 0.05), LAMP1 (p < 0.001) and pertinent ultrastructural markers. We propose that altered mitochondrial bioenergetics and cristae architecture probably induce mitophagy, leading to autophagy and consequent neuronal dysfunction in rabies.
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Virus de la Rabia , Rabia , Animales , Encéfalo/metabolismo , Perros , Humanos , Mitocondrias/metabolismo , Proteómica , Rabia/metabolismo , Rabia/patología , Virus de la Rabia/fisiologíaRESUMEN
There are several neurological diseases wherein skin biopsy is useful for diagnosis, even in the absence of skin involvement. Skin biopsy is especially relevant in diseases in which the metabolic error is unknown or has no available diagnostic biochemical test. Skin biopsy, being relatively noninvasive, obviates the need for an invasive procedure such as a brain biopsy. These disorders wherein skin biopsies are particularly useful include the progressive myoclonic epilepsies, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), neuroaxonal dystrophy, and small fiber neuropathies (SFN). We review the role of skin biopsy in such conditions with notes on preferred sites and techniques.
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CADASIL , Enfermedades de la Piel , Biopsia , Humanos , Imagen por Resonancia Magnética , Piel , Enfermedades de la Piel/diagnósticoRESUMEN
Foot-and-mouth disease virus (FMDV) is a picornavirus that causes contagious acute infection in cloven-hoofed animals. FMDV replication-associated viral protein expression induces endoplasmic reticulum (ER) stress and the unfolded protein response (UPR), in turn inducing autophagy to restore cellular homeostasis. We observed that inhibition of BiP (also known as HSPA5 and GRP78), a master regulator of ER stress and UPR, decreased FMDV infection confirming their involvement. Further, we show that the FMDV infection induces UPR mainly through the PKR-like ER kinase (PERK; also known as EIF2AK3)-mediated pathway. Knockdown of PERK and chemical inhibition of PERK activation resulted in decreased expression of FMDV proteins along with the reduction of autophagy marker protein LC3B-II [the lipidated form of LC3B (also known as MAP1LC3B)]. There are conflicting reports on the role of autophagy in FMDV multiplication. Our study systematically demonstrates that during FMDV infection, PERK-mediated UPR stimulated an increased level of endogenous LC3B-II and turnover of SQSTM1, thus confirming the activation of functional autophagy. Modulation of the UPR and autophagy by pharmacological and genetic approaches resulted in reduced numbers of viral progeny, by enhancing the antiviral interferon response. Taken together, this study underscores the prospect of exploring PERK-mediated autophagy as an antiviral target.
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Virus de la Fiebre Aftosa , Animales , Antivirales/farmacología , Autofagia , Estrés del Retículo Endoplásmico , Virus de la Fiebre Aftosa/metabolismo , Interferones , Respuesta de Proteína Desplegada , eIF-2 Quinasa/genética , eIF-2 Quinasa/metabolismoRESUMEN
Drug-resistant tuberculosis is being increasingly recognized and is one among the leading cause of death worldwide. Remarkable impermeability of cell wall to antituberculous drugs protects the mycobacteria from drug action. The present study analyzed the cell wall thickness among first-line drug resistant and sensitive Mycobacterium tuberculosis (Mtb) isolated from cerebrospinal fluid by transmission electron microscopy (TEM). The average thickness of the cell wall of sensitive isolates was 13.60 ± 0.98 nm. The maximum difference (26.48%) in the cell wall thickness was seen among multi-drug resistant (18.50 ± 1.71 nm) isolates and the least difference (4.14%) was shown by streptomycin-resistant (14.18 ± 1.38 nm) isolates. The ultrastructural study showed evident differences in the cell wall thickness among sensitive and resistant isolates. Preliminary TEM examination of cells indicates that morphological changes occur in the cell wall which might be attributed to the drug resistance. The thickened wall of Mtb appears to help the bacilli to overcome the action of antituberculous drugs.
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Pared Celular/ultraestructura , Farmacorresistencia Bacteriana , Mycobacterium tuberculosis/ultraestructura , Antituberculosos/farmacología , Biometría , Líquido Cefalorraquídeo/microbiología , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Meníngea/microbiologíaRESUMEN
Disease modeling has become challenging in the context of amyotrophic lateral sclerosis (ALS), as obtaining viable spinal motor neurons from postmortem patient tissue is an unlikely possibility. Limitations in the animal models due to their phylogenetic distance from human species hamper the success of translating possible findings into therapeutic options. Accordingly, there is a need for developing humanized models as a lead towards identifying successful therapeutic possibilities. In this study, human embryonic stem cells-BJNHem20-were differentiated into motor neurons expressing HB9, Islet1, and choline acetyl transferase using retinoic acid and purmorphamine. These motor neurons discharged spontaneous action potentials with two different frequencies (< 5 and > 5 Hz), and majority of them were principal neurons firing with < 5 Hz. Exposure to cerebrospinal fluid from ALS patients for 48 h induced several degenerative changes in the motor neurons as follows: cytoplasmic changes such as beading of neurites and vacuolation; morphological alterations, viz., dilation and vacuolation of mitochondria, curled and closed Golgi architecture, dilated endoplasmic reticulum, and chromatin condensation in the nucleus; lowered activity of different mitochondrial complex enzymes; reduced expression of brain-derived neurotrophic factor; up-regulated neurofilament phosphorylation and hyperexcitability represented by increased number of spikes. All these changes along with the enhanced expression of pro-apoptotic proteins-Bax and caspase 9-culminated in the death of motor neurons.
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Esclerosis Amiotrófica Lateral/metabolismo , Líquido Cefalorraquídeo , Células Madre Embrionarias Humanas/efectos de los fármacos , Neuronas Motoras/citología , Células Cultivadas , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Femenino , Células Madre Embrionarias Humanas/citología , Humanos , Filamentos Intermedios/metabolismo , Masculino , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neuronas Motoras/efectos de los fármacos , Degeneración Nerviosa/patología , Médula Espinal/efectos de los fármacos , Médula Espinal/patologíaRESUMEN
The precise role of autophagy in P. falciparum remains largely unknown. Although a limited number of autophagy genes have been identified in this apicomplexan, only PfAtg8 has been characterized to a certain extent. On the basis of the expression levels of PfAtg8 and the putative PfAtg5, we report that the basal autophagy in this parasite is quite robust and mediates not only the intraerythrocytic development but also fresh invasion of red blood cells (RBCs) in the subsequent cycles. We demonstrate that the basal autophagy responds to both inducers and inhibitors of autophagy. In addition, the parasite survival upon starvation is temporally governed by the autophagy status. Brief periods of starvation, which induces autophagy, help survival while prolonged starvation decreases autophagy leading to stalled parasite growth and reduced invasion. Thus, starvation-induced autophagy is context dependent. Importantly, we report characterization of another autophagy marker in this parasite, the putative PfAtg5 (Pf3D7_1430400). PfAtg5 is expressed in all the intraerythrocytic stages and partially colocalizes with ER, mitochondria, apicoplast and PfAtg8. It is also present on the double membrane bound vesicles. Altogether, these studies pave way for the detailed dissection of P. falciparum autophagy machinery and insights into molecular and functional characterization of its players for developing new therapeutics as antimalarials.
RESUMEN
Cytoplasmic mislocalisation and aggregation of TDP-43 and FUS/TLS proteins in spinal motor neurons contribute to the pathogenesis of the highly fatal disorder amyotrophic lateral sclerosis (ALS). We investigated the neuroprotective effect of VEGF on expression of these proteins in the motor neuronal cell line NSC-34 modelled to reminisce sporadic form of ALS. We studied the expression of TDP-43 and FUS/TLS proteins after exposure to ALS-CSF and following VEGF supplementation by quantitative confocal microscopy and electron microscopy. ALS-CSF caused cytoplasmic overexpression of both the proteins and stress-granule formation in the cells. These alterations were alleviated by VEGF supplementation. The related ultrastructural changes like nuclear membrane dysmorphism and p-bodies associated changes were also reversed. However the protein expression did not completely translocate to the nucleus, as some cells continued to show to cytoplasmic mislocalisation. Thus, the present findings indicate that VEGF alleviates TDP43 and FUS pathology by complimenting its role in controlling apoptosis and reversing choline acetyl transferase expression. Hence, VEGF appears to target multiple pathogenic processes in the neurodegenerative cascade of ALS.
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Esclerosis Amiotrófica Lateral/líquido cefalorraquídeo , Citoplasma/metabolismo , Proteínas de Unión al ADN/biosíntesis , Proteína FUS de Unión a ARN/biosíntesis , Factor A de Crecimiento Endotelial Vascular/farmacología , Adulto , Esclerosis Amiotrófica Lateral/patología , Biomarcadores/líquido cefalorraquídeo , Línea Celular , Citoplasma/efectos de los fármacos , Citoplasma/patología , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: The survival of motor neurons is dependent upon neurotrophic factors both during childhood and adolescence and during adult life. In disease conditions, such as in patients with amyotrophic lateral sclerosis (ALS), the mRNA levels of trophic factors like brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), fibroblast growth factor-2 (FGF-2), and vascular endothelial growth factor are downregulated. This was replicated in our in vivo experimental system following the injection of cerebral spinal fluid (CSF) of sporadic ALS (ALS-CSF) patients. OBJECTIVE: To evaluate the protective role of BDNF in a model of sporadic ALS patients. METHODS: The expressions of endogenous BDNF, its receptor TrkB, the enzyme choline acetyl transferase (ChAT), and phosphorylated neurofilaments were studied in NSC-34 cells. The calcium-buffering and proapoptotic effects were assessed by calbindin-D28K and caspase-3 expression, respectively. RESULTS: ALS-CSF considerably depleted the endogenous BDNF protein, while its effect on IGF-1 and FGF-2 was inconsequential; this indirectly indicates a key role for BDNF in supporting motor neuronal survival. The exogenous supplementation of BDNF reversed autocrine expression; however, it may not be completely receptor mediated, as the TrkB levels were not restored. BDNF completely revived ChAT expression. It may inhibit apoptosis by restoring Ca2+ homeostasis, since caspase-3 and calbindin-D28K expression was back to normal. The organellar ultrastructural changes were only partially reversed. CONCLUSION: Our study provides evidence that BDNF supplementation ameliorates most but not all degenerative changes. The incomplete revival at the ultrastructural level signifies the requirement of factors other than BDNF for near-total protection of motor neurons, and, to an extent, it explains why only a partial success is achieved in clinical trials with BDNF in ALS patients.
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Esclerosis Amiotrófica Lateral/líquido cefalorraquídeo , Factor Neurotrófico Derivado del Encéfalo/farmacología , Neuronas Motoras/efectos de los fármacos , Degeneración Nerviosa/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Recuperación de la Función/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Calcio/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Humanos , Filamentos Intermedios/efectos de los fármacos , Filamentos Intermedios/metabolismo , Filamentos Intermedios/patología , Ratones , Neuronas Motoras/fisiología , Neuronas Motoras/ultraestructura , Degeneración Nerviosa/patología , Degeneración Nerviosa/fisiopatología , Ratas Wistar , Receptor trkB/metabolismo , Recuperación de la Función/fisiología , Médula Espinal/efectos de los fármacos , Médula Espinal/patología , Médula Espinal/fisiopatologíaRESUMEN
The present study was undertaken to determine the membrane-stabilizing effect of Bio-tea in the prevention of myocardial injury caused by isoproterenol in rats. The efficiency of Bio-tea pretreatment was compared against black tea pretreatment and the positive control (rats with isoproterenol-induced myocardial infarction) and negative control (normal control rats). For this purpose, biochemical analysis of the in vivo antioxidants (superoxide dismutase, catalase, and reduced glutathione), glycoprotein components (hexose, hexosamine, sialic acid, and fucose), lipids (total, ester and free cholesterol, triglycerides, free fatty acids, and phospholipids), and transmembrane protein activities (Na+/K+ ATPase, Ca2+ ATPase, and Mg2+ ATPase) was carried out along with the histological and ultrastructural study of the myocardial tissue. Induction of myocardial infarction using isoproterenol resulted in a significant decrease in tissue antioxidants and an increase in the levels of total, ester and free cholesterol, triglycerides, free fatty acids, and glycoprotein components in plasma and heart. The phospholipid content showed an increase in plasma and a simultaneous decrease in the heart tissue, while the Na+/K+ ATPase activity decreased and Ca2+ ATPase and Mg2+ ATPase activities increased, resulting in destabilization of the membranes. Pretreatment with Bio-tea was able to bring these components to near normal, indicating its reactive-oxygen-species-scavenging, lipid-lowering, membrane-stabilizing and glycoprotein-modulating effects and lending credibility to the regular use of Bio-tea.
RESUMEN
Chordoid glioma (CG) is a World Health Organization classified grade II tumor located exclusively in the region of anterior third ventricle. Association of CG with other lesions is extremely rare. We report a case of CG in a 45-year-old male coexisting with an epidermoid cyst in the third ventricle. Ultrastructural examination of the CG revealed microvilli, junctional complexes, and intermediate filaments within the cytoplasm suggesting origin from specialized ependyma. The association of the 2 lesions appears coincidental as convincing evidence for a common histogenesis was not found.
Asunto(s)
Encefalopatías/complicaciones , Neoplasias del Ventrículo Cerebral/complicaciones , Quiste Epidérmico/complicaciones , Glioma/complicaciones , Tercer Ventrículo/patología , Biomarcadores de Tumor/análisis , Encefalopatías/patología , Neoplasias del Ventrículo Cerebral/patología , Neoplasias del Ventrículo Cerebral/ultraestructura , Quiste Epidérmico/patología , Quiste Epidérmico/ultraestructura , Glioma/patología , Glioma/ultraestructura , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Tercer Ventrículo/ultraestructuraRESUMEN
In our laboratory, we have developed (1) an in vitro model of sporadic Amyotrophic Lateral Sclerosis (sALS) involving exposure of motor neurons to cerebrospinal fluid (CSF) from sALS patients and (2) an in vivo model involving intrathecal injection of sALS-CSF into rat pups. In the current study, we observed that spinal cord extract from the in vivo sALS model displayed elevated reactive oxygen species (ROS) and mitochondrial dysfunction. Quantitative proteomic analysis of sub-cellular fractions from spinal cord of the in vivo sALS model revealed down-regulation of 35 mitochondrial proteins and 4 lysosomal proteins. Many of the down-regulated mitochondrial proteins contribute to alterations in respiratory chain complexes and organellar morphology. Down-regulated lysosomal proteins Hexosaminidase, Sialidase and Aryl sulfatase also displayed lowered enzyme activity, thus validating the mass spectrometry data. Proteomic analysis and validation by western blot indicated that sALS-CSF induced the over-expression of the pro-apoptotic mitochondrial protein BNIP3L. In the in vitro model, sALS-CSF induced neurotoxicity and elevated ROS, while it lowered the mitochondrial membrane potential in rat spinal cord mitochondria in the in vivo model. Ultra structural alterations were evident in mitochondria of cultured motor neurons exposed to ALS-CSF. These observations indicate the first line evidence that sALS-CSF mediated mitochondrial and lysosomal defects collectively contribute to the pathogenesis underlying sALS.
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Esclerosis Amiotrófica Lateral/líquido cefalorraquídeo , Lisosomas/metabolismo , Mitocondrias/fisiología , Extractos de Tejidos/farmacología , Adulto , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Células Cultivadas , Femenino , Humanos , Inyecciones Espinales , Masculino , Potencial de la Membrana Mitocondrial , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Proteínas Mitocondriales/metabolismo , Neuronas Motoras/metabolismo , Neuronas Motoras/ultraestructura , Estrés Oxidativo , Proteoma/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Proteínas Supresoras de Tumor/metabolismoRESUMEN
The Fourier-Transform Infrared and Fourier-Transform Raman spectra of 2,2-diphenyl-4-(piperidin-1-yl)butanamide were recorded in the region 4000-400 cm(-1) and 4000-0 cm(-1). The vibrational wavenumbers are computed using HF and DFT methods. The complete vibrational assignments were performed on the basis of potential energy distribution using GAR2PED program. The geometrical parameters of the title compound are in agreement with the XRD data. From the MEP study, the negative electrostatic potential regions are mainly localized of carbonyl group and are possible sites for electrophilic attack and the positive regions are localized all the rings, indicating possible sites for nucleophilic attack. Stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using natural bond orbital analysis. The calculated HOMO and LUMO energies also confirm that charge transfer occurs within the molecule. PASS analysis of the title compound predicts among other activities, antidyskinetic activity. Molecular docking results draw us to the conclusion that the compound might exhibit inhibitory activity against adenosine A2A and may act as antidyskinetic agent.
Asunto(s)
Amidas/química , Compuestos de Bifenilo/química , Piperidinas/química , Amidas/farmacocinética , Compuestos de Bifenilo/farmacocinética , Modelos Moleculares , Conformación Molecular , Simulación del Acoplamiento Molecular , Piperidinas/farmacocinética , Teoría Cuántica , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Electricidad Estática , VibraciónRESUMEN
Astroblastomas are extremely rare neuroepithelial tumors of uncertain histogenesis, affecting children and young adults, and constitute a new addition to the WHO 2000 classification of CNS tumors. We report the largest series of nine cases diagnosed in a single institute over the last 13 years and review published literature. Mean age at presentation was 12.8 years (range: 22 months to 27years). Seven out of nine cases were supratentorial (frontal/frontoparietal - three, parieto-occipital - three, parafalcine - one), one was intraventricular and another was optochaismatic/suprasellar. Five cases were high grade (anaplastic) astroblastomas with Ki-67 labeling index of 8-10%. Immunohistochemical and ultrastructural evidence suggesting origin from cells intermediate between ependymocytes and astrocytes is presented. The histogenetic origin of these tumors remains speculative. But the lack of Isocitrate dehydrogenase 1 (IDH1) mutation as detected by immunohistochemistry in this study, which is similar to ependymomas supports putative origin from ependymoglial cells. Out of the nine cases, recurrence was noted in one case, 12 months after gross total resection with progression to high grade in the recurrent tumor. There is no recommended treatment protocol due to the rarity of this entity and prognostic factors are yet to be established.
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Neoplasias Encefálicas/genética , Neoplasias Encefálicas/ultraestructura , Células Ependimogliales/ultraestructura , Isocitrato Deshidrogenasa/genética , Neoplasias Neuroepiteliales/genética , Neoplasias Neuroepiteliales/ultraestructura , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Mutación , Neoplasias Neuroepiteliales/etiología , Adulto JovenRESUMEN
Stress and depression are associated with impaired neuroplasticity in the hippocampus; there is a decrease in neurogenesis, which is hypothesized to decrease the adaptative competence of the organism. Representative light microscopy images are presented which show that 6 once-daily electroconvulsive shocks (ECS), dose-dependently increased new cell formation in the subgranular region of the hippocampus in healthy adult male Wistar rats (10 sections per rat, 3 rats in each of sham ECS, 10 mC, and 40 mC groups). These neuroplasticity changes, demonstrated 1 month after the last ECS, may explain a part of the mechanism of action of electroconvulsive therapy in conditions such as depression.
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Terapia Electroconvulsiva , Hipocampo/citología , Hipocampo/ultraestructura , Plasticidad Neuronal/fisiología , Animales , Proliferación Celular , Masculino , Ratas , Ratas WistarRESUMEN
Memory impairment during aging is believed to be a consequence of decline in neuronal function and increase in neurodegeneration. Accumulation of oxidative damage and reduction of antioxidant defense system play a key role in organismal aging and functional senescence. In our study, we examined the age-related memory impairment (AMI) in relation to oxidative stress using Drosophila model. We observed a decline in cognitive function in old flies with respect to both short-lived and consolidated forms of olfactory memory. Light and electron microscopy of mushroom bodies revealed a reduction in the number of synapses and discernible architectural defects in mitochondria. An increase in neuronal apoptosis in Kenyon cells was also evident in aged flies. Biochemical investigations revealed a comparable age-associated decrease in the activity of antioxidant enzymes such as catalase and superoxide dismutase as well as the GSH level, accompanied by an increase in the level of lipid peroxidation and generation of reactive oxygen species in the brain. There was no significant difference in the activity level of AChE and BChE enzymes between different age groups while immunohistochemical studies showed a significant decrease in the level of ChAT in 50-day-old flies. RNAi-mediated silencing of cat and sod1 genes caused severe memory impairment in 15-day-old flies, whereas, over-expression of cat gene could partially rescue the memory loss in the old flies. We demonstrated that a Drosophila long-lived strain, possessing enhanced activity of antioxidant enzymes and higher rate of resistance to oxidative stress, shows lower extent of AMI compared to normal lifespan strain. Present study provides evidence for involvement of oxidative stress in AMI in Drosophila.
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Envejecimiento , Encéfalo/patología , Drosophila melanogaster/fisiología , Trastornos de la Memoria/patología , Estrés Oxidativo/fisiología , Acetilcolina/metabolismo , Envejecimiento/genética , Animales , Animales Modificados Genéticamente , Encéfalo/metabolismo , Encéfalo/ultraestructura , Catalasa/genética , Catalasa/metabolismo , Colina/análogos & derivados , Colina/metabolismo , Colina O-Acetiltransferasa/metabolismo , Condicionamiento Clásico/fisiología , Proteínas de Drosophila/genética , Regulación de la Expresión Génica/genética , Glutatión/metabolismo , Peroxidación de Lípido/genética , Trastornos de la Memoria/genética , Cuerpos Pedunculados/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Olfato/fisiología , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa-1 , Factores de TiempoRESUMEN
The Indian Bombyxmori Densovirus type 2 isolate (DNV-2), revealed closer homology with Japanese Yamanashi isolate. PCR and qPCR analyses indicated severe and widespread prevalence of the virus in flacherie diseased B. mori under Indian field conditions. Viral inoculation revealed typical flacherie disease symptoms and transmission electron microscopy revealed damage of infected midgut tissue cells. The nsd-2 gene for resistance to DNV-2 restricted viral proliferation in B. mori. This study indicates possible major role of the Indian DNV-2 isolate in causing flacherie disease in B. mori leading to crop loss. A detailed molecular characterization of the whole viral genome including nsd-2 gene expression profiling is essential to develop appropriate diagnostic tools and control strategies.
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Bombyx/genética , Bombyx/virología , Densovirus/genética , Resistencia a la Enfermedad/genética , Animales , Bombyx/inmunología , Genoma Viral , Humanos , India , Proteínas de Insectos/genética , Microscopía Electrónica de Transmisión , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
BACKGROUND: In animal models, stress and depression are associated with excitatory changes in the amygdala; this aberrant neuroplasticity may represent increased fear learning, explaining the anxiety, fear, and related symptoms that characterize clinical depression. MATERIALS AND METHODS: In a pilot investigation, we treated adult, male, Wistar rats with sham electroconvulsive shocks (ECS; n=3), low-dose ECS (10 mC; n=3), and high-dose ECS (60 mC; n=3). The rats were sacrificed 1 month after the last of 6 once-daily ECS and, after dissection, sections of the basolateral amygdala were examined using transmission electron microscopy under low (×11,000) and high (×30,000) magnification. RESULTS: In each group, 4 fields were examined under low magnification and 6 fields under high magnification. The number of excitatory synapses and the ratio of excitatory to inhibitory synapses were both numerically lower with ECS than with sham ECS, and the effect was stronger in the high-dose ECS group (statistical analyses were not performed because this was a pilot study). CONCLUSIONS: By reducing the number of excitatory synapses and the ratio of excitatory to inhibitory synapses, ECT (especially high-dose ECT) may reduce stress-induced excitatory changes in the amygdala. These changes may help explain a part of the benefits observed with ECT in conditions such as depression and post-traumatic stress disorder.
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In foot-and-mouth disease (FMD) control programme, liquid-phase blocking ELISA (LPBE) is widely used to assay vaccine-induced seroconversion. Currently, the assay utilizes inactivated FMD virus antigen for the detection of antibodies in serum samples. To develop a non-infectious substitute for the antigen in LPBE, we expressed the structural polypeptide of FMDV (serotype A) using a baculovirus expression system, and show that inclusion of viral 3C with reduced protease activity resulted in a higher yield of structural proteins. Structural proteins expressed in insect cells assembled into empty virus-like particles (VLPs) and showed antigenicity comparable to chemically inactivated FMDV. Screening of serum samples from FMD-vaccinated cattle showed that the test performance of VLP-LPBE had a correlation of 0.89 with conventional inactivated virus antigen LPBE. The VLP-LPBE developed here demonstrates the diagnostic application of recombinant FMDV VLPs in monitoring seroconversion following FMD vaccination.
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Anticuerpos Antivirales/sangre , Antígenos Virales , Proteínas de la Cápside , Virus de la Fiebre Aftosa/inmunología , Fiebre Aftosa/inmunología , Medicina Veterinaria/métodos , Vacunas Virales/inmunología , Animales , Antígenos Virales/inmunología , Proteínas de la Cápside/inmunología , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/prevención & control , Ensayo de Inmunoadsorción Enzimática/métodos , Fiebre Aftosa/prevención & control , Proteínas Recombinantes/inmunología , Pruebas Serológicas/métodosRESUMEN
Salmonella has evolved several strategies to counteract intracellular microbicidal agents like reactive oxygen and nitrogen species. However, it is not yet clear how Salmonella escapes lysosomal degradation. Some studies have demonstrated that Salmonella can inhibit phagolysosomal fusion, whereas other reports have shown that the Salmonella-containing vacuole (SCV) fuses/interacts with lysosomes. Here, we have addressed this issue from a different perspective by investigating if the infected host cell has a sufficient quantity of lysosomes to target Salmonella. Our results suggest that SCVs divide along with Salmonella, resulting in a single bacterium per SCV. As a consequence, the SCV load per cell increases with the division of Salmonella inside the host cell. This demands more investment from the host cell to counteract Salmonella. Interestingly, we observed that Salmonella infection decreases the number of acidic lysosomes inside the host cell both in vitro and in vivo. These events potentially result in a condition in which an infected cell is left with insufficient acidic lysosomes to target the increasing number of SCVs, which favors the survival and proliferation of Salmonella inside the host cell.