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1.
ScientificWorldJournal ; 2021: 6649574, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33994883

RESUMEN

Garugapinnata Roxb. (Burseraceae) is a medium-sized tree widely available all over the tropical regions of Asia. Bryophyllum pinnatum (Lam) Oken. (Crassulaceae) is an indigenous and exotic plant grown in tropical regions. Both plants have been used for their anti-inflammatory, antioxidant, anticancer, wound healing, antidiabetic activities, etc. This investigation was designed to explore the result shown by methanolic extract of Garuga pinnata bark and Bryophyllum pinnatum leaves, on cognitive power and retention of the memory in experimental mice along with quantification of phenolic compounds and DPPH radicals neutralizing capacity. The memory-enhancing activity was determined by the elevated plus-maze method in Scopolamine-induced amnesic mice, using Piracetam as allopathic and Shankhpushpi as ayurvedic standard drugs. Two doses (200 and 400 mg/kg p.o.) of both extracts were administered to mice up to 8 consecutive days; transfer latency of individual group was recorded after 45 minutes and memory of the experienced things was examined after 1 day. DPPH assay method and the Folin-Ciocalteu method were employed to determine antioxidant potency and total phenol amount, respectively. 400 mg/kg of the methanolic B. pinnatum bark extract significantly improved memory and learning of mice with transfer latency (TL) of 32.75 s, which is comparable to that of standard Piracetam (21.78 s) and Shankhpushpi (27.83 s). Greater phenolic content was quantified in B. pinnatum bark extract (156.80 ± 0.33 µg GAE/mg dry extract) as well as the antioxidant potency (69.77% of free radical inhibition at the 100 µg/mL concentration). Our study proclaimed the scientific evidence for the memory-boosting effect of both plants.


Asunto(s)
Amnesia/tratamiento farmacológico , Antioxidantes/farmacología , Burseraceae/química , Kalanchoe/química , Nootrópicos/farmacología , Fitoquímicos/farmacología , Amnesia/inducido químicamente , Amnesia/fisiopatología , Animales , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Cognición/efectos de los fármacos , Cognición/fisiología , Femenino , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Aprendizaje por Laberinto/fisiología , Memoria/efectos de los fármacos , Memoria/fisiología , Ratones , Nootrópicos/aislamiento & purificación , Fenoles/farmacología , Fitoquímicos/aislamiento & purificación , Picratos/antagonistas & inhibidores , Piracetam/farmacología , Corteza de la Planta/química , Extractos Vegetales/química , Hojas de la Planta/química , Preparaciones de Plantas/farmacología , Escopolamina/administración & dosificación
2.
Hum Brain Mapp ; 42(10): 3202-3215, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33955088

RESUMEN

A major challenge in the cognitive training field is inducing broad, far-transfer training effects. Thus far, little is known about the neural mechanisms underlying broad training effects. Here, we tested a set of competitive hypotheses regarding the role of brain integration versus segregation underlying the broad training effect. We retrospectively analyzed data from a randomized controlled trial comparing neurocognitive effects of vision-based speed of processing training (VSOP) and an active control consisting of mental leisure activities (MLA) in older adults with MCI. We classified a subset of participants in the VSOP as learners, who showed improvement in executive function and episodic memory. The other participants in the VSOP (i.e., VSOP non-learners) and a subset of participants in the MLA (i.e., MLA non-learners) served as controls. Structural brain networks were constructed from diffusion tensor imaging. Clustering coefficients (CCs) and characteristic path lengths were computed as measures of segregation and integration, respectively. Learners showed significantly greater global CCs after intervention than controls. Nodal CCs were selectively enhanced in cingulate cortex, parietal regions, striatum, and thalamus. Among VSOP learners, those with more severe baseline neurodegeneration had greater improvement in segregation after training. Our findings suggest broad training effects are related to enhanced segregation in selective brain networks, providing insight into cognitive training related neuroplasticity.


Asunto(s)
Amnesia , Corteza Cerebral/patología , Disfunción Cognitiva , Remediación Cognitiva , Red Nerviosa/patología , Tálamo/patología , Anciano , Anciano de 80 o más Años , Amnesia/diagnóstico por imagen , Amnesia/patología , Amnesia/fisiopatología , Amnesia/terapia , Corteza Cerebral/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/terapia , Cuerpo Estriado , Imagen de Difusión Tensora , Femenino , Humanos , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Plasticidad Neuronal/fisiología , Desempeño Psicomotor/fisiología , Estudios Retrospectivos , Tálamo/diagnóstico por imagen
3.
Trials ; 20(1): 518, 2019 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-31429790

RESUMEN

BACKGROUND: Amnestic mild cognitive impairment (aMCI) is a syndrome characterized by significant forgetfulness that does not meet the criteria of dementia. Individuals with aMCI are at greater risk of progressing to dementia. Current studies suggest that good sleep quality is linked with preserved cognition in the elderly, and sleep complaints are common among the elderly with amnesia. Therefore, improving their sleep may be helpful for maintaining and improving their cognitive capacity. According to the theory of traditional Chinese medicine, Yi-Zhi-An-Shen is an herbal compound which may ameliorate forgetfulness and sleep disorders. As growing evidence indicates that the gut microbiome is associated with major mental symptoms, a hypothesis was proposed that Yi-Zhi-An-Shen granules (YZASG) might work by alternating microbial abundance and diversity. In this study, the investigators intend to assess the efficacy of YZASG on global cognition in the elderly suffering from aMCI and evaluate its safety as well as its potential mechanisms via sleep quality, fecal microbial 16S ribosomal DNA and metagenomics analyses, and serum markers. METHODS/DESIGN: This study is a randomized, double-blind, placebo-controlled clinical trial. A total of 80 patients (aged 60-85 years) will be recruited and allocated randomly to a treatment group and a placebo group in a 1:1 ratio and will then be administered YZASG or isodose placebo three times a day. The intervention course is 16 weeks, with an 18 months follow-up. The primary outcome is the Alzheimer's Disease Assessment Scale-Cognitive Subscale. Secondary outcome measures are the Mini-Mental State Examination, Montreal Cognitive Assessment, Pittsburgh Sleep Quality Index, serum concentrations of immunological factors and inflammatory cytokines, and fecal microbiota. Fecal microbiota will only be collected at the baseline and endpoint of the intervention. DISCUSSION: The results of this trial will be conducive to assessing the safety and effectiveness on cognition of YZASG in intervening aMCI among the elderly and determining if it takes effect via the improvement of sleep quality, regulation of gut microbiota, and concentration of certain serum markers. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03601000 . Registered on 26 July 2018.


Asunto(s)
Amnesia/tratamiento farmacológico , Cognición/efectos de los fármacos , Disfunción Cognitiva/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Hipnóticos y Sedantes/uso terapéutico , Memoria/efectos de los fármacos , Nootrópicos/uso terapéutico , Sueño/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Amnesia/diagnóstico , Amnesia/fisiopatología , Amnesia/psicología , Biomarcadores/sangre , China , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/psicología , Método Doble Ciego , Medicamentos Herbarios Chinos/efectos adversos , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Hipnóticos y Sedantes/efectos adversos , Mediadores de Inflamación/sangre , Masculino , Persona de Mediana Edad , Nootrópicos/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Tiempo , Resultado del Tratamiento
4.
Bioengineered ; 10(1): 353-364, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31431119

RESUMEN

Cinnabar is an attractive mineral with many different uses. It is reported that cinnabar is one of the traditional Chinese's medicines extensively use. The main objective of this critical review is to identify the current overview, concept and chemistry of cinnabar, which includes the process developments, challenges, and diverse options for pharmacology research. It is used as a medicine through probable toxicity, especially when taking overdoes. This review is the first to describe the toxicological effects of cinnabar and its associated compounds. Nuclear magnetic resonance (NMR) dependent metabolomics could be useful for examination of the pharmaceutical consequence. The analysis indicated that the accurate preparation methods, appropriate doses, disease status, ages with drug combinations are significant factors for impacting the cinnabar toxicity. Toxicologically, synthetic mercury sulfide or cinnabar should be notable for mercuric chloride, mercury vapor and methyl mercury for future protection and need several prominent advancements in cinnabar research.


Asunto(s)
Amnesia/tratamiento farmacológico , Hipnóticos y Sedantes/uso terapéutico , Compuestos de Mercurio/uso terapéutico , Nootrópicos/uso terapéutico , Agitación Psicomotora/tratamiento farmacológico , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/patología , Amnesia/fisiopatología , Animales , Cálculo de Dosificación de Drogas , Historia Antigua , Humanos , Hipnóticos y Sedantes/química , Hipnóticos y Sedantes/aislamiento & purificación , Hipnóticos y Sedantes/toxicidad , Medicina Ayurvédica/historia , Medicina Ayurvédica/métodos , Medicina Tradicional China/historia , Medicina Tradicional China/métodos , Compuestos de Mercurio/química , Compuestos de Mercurio/aislamiento & purificación , Compuestos de Mercurio/toxicidad , Ratones , Nootrópicos/química , Nootrópicos/aislamiento & purificación , Nootrópicos/toxicidad , Agitación Psicomotora/fisiopatología , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Pruebas de Toxicidad
5.
Neuropsychologia ; 132: 107104, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31260681

RESUMEN

Despite their severely impaired episodic memory, individuals with amnesia are able to comprehend ongoing events. Online representations of a current event are thought to be supported by a network of regions centred on the posterior midline cortex (PMC). By contrast, episodic memory is widely believed to be supported by interactions between the hippocampus and these cortical regions. In this MRI study, we investigated the encoding and retrieval of real life-like events (video clips) in a patient with severe amnesia likely resulting from a stroke to the right (and possibly the left) thalamus, and a group of 20 age-matched controls. Structural MRI revealed grey matter reductions in left hippocampus and left thalamus in comparison to controls. We first characterised the regions activated in the controls while they watched and retrieved the videos. There were no differences in activation between the patient and controls in any of the regions. We then identified a widespread network of brain regions, including the hippocampus, that were functionally connected with the PMC in controls. However, in the patient there was a specific reduction in functional connectivity between the PMC and a region of left hippocampus when both watching and attempting to retrieve the videos. A follow up analysis of the control group revealed that, when watching the videos, the functional connectivity between these two regions was correlated with memory performance. Taken together, these findings support the view that the interactions between the PMC and the hippocampus enable the encoding and retrieval of naturalistic events.


Asunto(s)
Amnesia/fisiopatología , Conectoma , Hipocampo/fisiopatología , Red Nerviosa/fisiopatología , Anciano , Amnesia/diagnóstico por imagen , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Tálamo/diagnóstico por imagen , Tálamo/patología
6.
Elife ; 82019 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-31282861

RESUMEN

Patients with hippocampal amnesia play a central role in memory neuroscience but the neural underpinnings of amnesia are hotly debated. We hypothesized that focal hippocampal damage is associated with changes across the extended hippocampal system and that these, rather than hippocampal atrophy per se, would explain variability in memory between patients. We assessed this hypothesis in a uniquely large cohort of patients (n = 38) after autoimmune limbic encephalitis, a syndrome associated with focal structural hippocampal pathology. These patients showed impaired recall, recognition and maintenance of new information, and remote autobiographical amnesia. Besides hippocampal atrophy, we observed correlatively reduced thalamic and entorhinal cortical volume, resting-state inter-hippocampal connectivity and activity in posteromedial cortex. Associations of hippocampal volume with recall, recognition, and remote memory were fully mediated by wider network abnormalities, and were only direct in forgetting. Network abnormalities may explain the variability across studies of amnesia and speak to debates in memory neuroscience.


Asunto(s)
Amnesia/fisiopatología , Hipocampo/fisiopatología , Memoria/fisiología , Red Nerviosa/fisiopatología , Adolescente , Adulto , Anciano , Amnesia/complicaciones , Atrofia , Enfermedades Autoinmunes/complicaciones , Enfermedades Autoinmunes/fisiopatología , Estudios de Cohortes , Femenino , Hipocampo/patología , Humanos , Encefalitis Límbica/complicaciones , Encefalitis Límbica/fisiopatología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/anomalías , Tálamo/patología , Tálamo/fisiopatología
7.
J Neurosci ; 39(34): 6696-6713, 2019 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-31235646

RESUMEN

Diencephalic amnesia can be as debilitating as the more commonly known temporal lobe amnesia, yet the precise contribution of diencephalic structures to memory processes remains elusive. Across four cohorts of male rats, we used discrete lesions of the mammillothalamic tract to model aspects of diencephalic amnesia and assessed the impact of these lesions on multiple measures of activity and plasticity within the hippocampus and retrosplenial cortex. Lesions of the mammillothalamic tract had widespread indirect effects on hippocampocortical oscillatory activity within both theta and gamma bands. Both within-region oscillatory activity and cross-regional synchrony were altered. The network changes were state-dependent, displaying different profiles during locomotion and paradoxical sleep. Consistent with the associations between oscillatory activity and plasticity, complementary analyses using several convergent approaches revealed microstructural changes, which appeared to reflect a suppression of learning-induced plasticity in lesioned animals. Together, these combined findings suggest a mechanism by which damage to the medial diencephalon can impact upon learning and memory processes, highlighting an important role for the mammillary bodies in the coordination of hippocampocortical activity.SIGNIFICANCE STATEMENT Information flow within the Papez circuit is critical to memory. Damage to ascending mammillothalamic projections has consistently been linked to amnesia in humans and spatial memory deficits in animal models. Here we report on the changes in hippocampocortical oscillatory dynamics that result from chronic lesions of the mammillothalamic tract and demonstrate, for the first time, that the mammillary bodies, independently of the supramammillary region, contribute to frequency modulation of hippocampocortical theta oscillations. Consistent with the associations between oscillatory activity and plasticity, the lesions also result in a suppression of learning-induced plasticity. Together, these data support new functional models whereby mammillary bodies are important for coordinating hippocampocortical activity rather than simply being a relay of hippocampal information as previously assumed.


Asunto(s)
Amnesia/fisiopatología , Diencéfalo/fisiopatología , Hipocampo/fisiopatología , Tubérculos Mamilares/fisiopatología , Vías Nerviosas/fisiopatología , Tálamo/fisiopatología , Amnesia/diagnóstico por imagen , Animales , Diencéfalo/diagnóstico por imagen , Electroencefalografía , Ritmo Gamma , Hipocampo/diagnóstico por imagen , Locomoción , Imagen por Resonancia Magnética , Masculino , Tubérculos Mamilares/diagnóstico por imagen , Aprendizaje por Laberinto , Vías Nerviosas/diagnóstico por imagen , Plasticidad Neuronal , Ratas , Sueño REM , Memoria Espacial , Tálamo/diagnóstico por imagen , Ritmo Teta
8.
Brain Nerve ; 70(11): 1203-1208, 2018 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-30416113

RESUMEN

Confabulation is defined as the production of narrative descriptions of events that never happened, and is often observed in amnesia with basal forebrain lesions. However, little is known about the possible mechanisms related to confabulation. In this review article, we summarized previous neuropsychological and neuroimaging studies associated with confabulation, and proposed a hypothetical mechanism of confabulation. Previous studies have demonstrated that amnesic patients with confabulation after basal forebrain damage are impaired in the processing of time-related information in episodic memory and that activation of this region is significant during the processing of time-related information in episodic memory. In addition, confabulating patients with basal forebrain lesions extending to the medial prefrontal cortex (mPFC), medial temporal, and thalamic regions are likely to show significant disturbances in age-awareness and significant false memories in personally experienced events. Given the importance of the mPFC in the self-referential process and of the hippocampus in the integration of episodic components, the basal forebrain region could play an important role in orienting the self in time by acting as an interface between the mPFC and the hippocampus. Confabulation in basal forebrain amnesia could be caused by a decline of the time-self interaction.


Asunto(s)
Amnesia/fisiopatología , Deluciones , Memoria Episódica , Percepción del Tiempo , Hipocampo , Humanos , Pruebas Neuropsicológicas , Corteza Prefrontal/patología , Lóbulo Temporal/patología , Tálamo/patología
9.
Brain Nerve ; 70(7): 771-782, 2018 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-29997273

RESUMEN

It has been proposed that there are two distinct neural circuits underlying human episodic memory. A first circuit connects the hippocampus to the anterior nucleus of the thalamus (hippocampal-anterior thalamic memory circuit). A second circuit conveys fibers from the perirhinal cortex to the dorsomedial nucleus of the thalamus (perirhinal-medial dorsal thalamic memory circuit). In this article, we briefly review research investigating the functional roles of the two circuits in memory, including neuropsychological studies of amnesic patients with thalamic infarcts and functional magnetic resonance imaging (fMRI) studies of healthy participants. On the basis of the findings, we discuss the relationship between thalamic structures, episodic memory, and its disorders (thalamic amnesia).


Asunto(s)
Amnesia/fisiopatología , Hipocampo/fisiología , Memoria Episódica , Tálamo/fisiopatología , Humanos
10.
Neuropsychologia ; 117: 332-338, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29932960

RESUMEN

During conversation, people integrate information from co-speech hand gestures with information in spoken language. For example, after hearing the sentence, "A piece of the log flew up and hit Carl in the face" while viewing a gesture directed at the nose, people tend to later report that the log hit Carl in the nose (information only in gesture) rather than in the face (information in speech). The cognitive and neural mechanisms that support the integration of gesture with speech are unclear. One possibility is that the hippocampus - known for its role in relational memory and information integration - is necessary for integrating gesture and speech. To test this possibility, we examined how patients with hippocampal amnesia and healthy and brain-damaged comparison participants express information from gesture in a narrative retelling task. Participants watched videos of an experimenter telling narratives that included hand gestures that contained supplementary information. Participants were asked to retell the narratives and their spoken retellings were assessed for the presence of information from gesture. For features that had been accompanied by supplementary gesture, patients with amnesia retold fewer of these features overall and fewer retellings that matched the speech from the narrative. Yet their retellings included features that contained information that had been present uniquely in gesture in amounts that were not reliably different from comparison groups. Thus, a functioning hippocampus is not necessary for gesture-speech integration over short timescales. Providing unique information in gesture may enhance communication for individuals with declarative memory impairment, possibly via non-declarative memory mechanisms.


Asunto(s)
Amnesia/patología , Amnesia/fisiopatología , Gestos , Hipocampo/patología , Desempeño Psicomotor/fisiología , Habla/fisiología , Estimulación Acústica , Anciano , Amnesia/diagnóstico por imagen , Femenino , Hipocampo/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
11.
Biomed Pharmacother ; 99: 198-204, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29334662

RESUMEN

BACKGROUND: Tetrapleura tetraptera (TT) and Quassia undulata (QU) are two predominant tropical ethnobotanicals with various medicinal values but are commonly used in folklore for the treatment of mental illness without justifiable mechanisms of action. AIM OF THE STUDY: To investigate the effects of aqueous extracts from TT fruits and QU leaves on the spatial and non-spatial working memory, antioxidant status and activities of neuronal marker enzymes of scopolamine-induced amnesic rats and thus, understand the possible mechanism of action of these plants. MATERIALS AND METHODS: Fifty-five albino rats were divided into eleven groups. Group I (normal rats) received normal saline (p.o), Group II-V (normal rats) administered with 50 and 300 mg/kg of each extract group VI (induced rats) received 2 mg/kg of scopolamine (i.p.), groups VII-X (induced rats) pretreated with 50 and 300 mg/kg of TT and QU extracts (p.o) before scopolamine administration, group XI (induced rats) treated with 2.5 mg/kg of donepezil. The treatment lasted for 14 days and amnesia was induced by a single dose of 2 mg/kg of scopolamine on the last day. Spatial (Y-maze) and non-spatial (novel objectect recoginiton test) working memories of the rats were tested. Thereafter, the animals were sacrificed and homogenates of isolated brain samples were assayed for cholinesterase activity and malondialdehyde (MDA) content. The phenolic characterisation of the samples was also carried out using HPLC-DAD chromatography. RESULTS: Administration of 2 mg/kg of scopolamine brought about a decrease in spatial and non-spatial memory indeces, increase in acetylcholinesterase and butyrylcholinesterase activities, as well as increased MDA content compared to the control. However, pretreatment with both extracts improved both spatial and non-spatial working memories and ameliorated the increased enzyme activities and MDA contents. Furthermore, the HPLC-DAD characterization of the extracts revealed the presence of p-coumaric acid, rutin, catechin, ellagic acid, quercetin, caffeic acid, chlorogenic acid and galic acid. CONCLUSION: The ability of the extracts to improved cognitive function and ameliorate impairment in cholinergic enzyme activities and antioxidant status in scopolamine-induced amnesic rats could help justify the possible neuroprotective properties of TT and QU and also explain possible mechanism of action of these ethnobotanicals as obtained in folklore medical practices.


Asunto(s)
Amnesia/tratamiento farmacológico , Amnesia/fisiopatología , Antioxidantes/farmacología , Colinérgicos/farmacología , Memoria a Corto Plazo/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Quassia/química , Tetrapleura/química , Acetilcolinesterasa/metabolismo , Animales , Encéfalo/enzimología , Cromatografía Líquida de Alta Presión , Etnobotánica , Conducta Exploratoria , Femenino , Peroxidación de Lípido/efectos de los fármacos , Aprendizaje por Laberinto/efectos de los fármacos , Extractos Vegetales/farmacología , Ratas , Escopolamina , Agua/química
13.
Brain Struct Funct ; 222(5): 2143-2156, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27783220

RESUMEN

Despite being historically one of the first brain regions linked to memory loss, there remains controversy over the core features of diencephalic amnesia as well as the critical site for amnesia to occur. The mammillary bodies and thalamus appear to be the primary locus of pathology in the cases of diencephalic amnesia, but the picture is complicated by the lack of patients with circumscribed damage. Impaired temporal memory is a consistent neuropsychological finding in Korsakoff syndrome patients, but again, it is unclear whether this deficit is attributable to pathology within the diencephalon or concomitant frontal lobe dysfunction. To address these issues, we used an animal model of diencephalic amnesia and examined the effect of mammillothalamic tract lesions on tests of recency memory. The mammillothalamic tract lesions severely disrupted recency judgements involving multiple items but left intact both recency and familiarity judgements for single items. Subsequently, we used disconnection procedures to assess whether this deficit reflects the indirect involvement of the prefrontal cortex. Crossed-lesion rats, with unilateral lesions of the mammillothalamic tract and medial prefrontal cortex in contralateral hemispheres, were unimpaired on the same recency tests. These results provide the first evidence for the selective importance of mammillary body efferents for recency memory. Moreover, this contribution to recency memory is independent of the prefrontal cortex. More broadly, these findings identify how specific diencephalic structures are vital for key elements of event memory.


Asunto(s)
Amnesia/fisiopatología , Diencéfalo/fisiopatología , Tubérculos Mamilares/fisiopatología , Trastornos de la Memoria/fisiopatología , Memoria/fisiología , Animales , Diencéfalo/patología , Lóbulo Frontal/patología , Masculino , Tubérculos Mamilares/patología , Trastornos de la Memoria/patología , Vías Nerviosas/patología , Vías Nerviosas/fisiopatología , Corteza Prefrontal/patología , Corteza Prefrontal/fisiopatología , Ratas , Tálamo/patología
14.
Cogn Affect Behav Neurosci ; 17(1): 24-76, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27905080

RESUMEN

How do the hippocampus and amygdala interact with thalamocortical systems to regulate cognitive and cognitive-emotional learning? Why do lesions of thalamus, amygdala, hippocampus, and cortex have differential effects depending on the phase of learning when they occur? In particular, why is the hippocampus typically needed for trace conditioning, but not delay conditioning, and what do the exceptions reveal? Why do amygdala lesions made before or immediately after training decelerate conditioning while those made later do not? Why do thalamic or sensory cortical lesions degrade trace conditioning more than delay conditioning? Why do hippocampal lesions during trace conditioning experiments degrade recent but not temporally remote learning? Why do orbitofrontal cortical lesions degrade temporally remote but not recent or post-lesion learning? How is temporally graded amnesia caused by ablation of prefrontal cortex after memory consolidation? How are attention and consciousness linked during conditioning? How do neurotrophins, notably brain-derived neurotrophic factor (BDNF), influence memory formation and consolidation? Is there a common output path for learned performance? A neural model proposes a unified answer to these questions that overcome problems of alternative memory models.


Asunto(s)
Aprendizaje/fisiología , Consolidación de la Memoria/fisiología , Modelos Neurológicos , Adaptación Psicológica/fisiología , Amnesia/fisiopatología , Amígdala del Cerebelo/fisiología , Animales , Parpadeo/fisiología , Corteza Cerebral/fisiología , Condicionamiento Psicológico/fisiología , Estado de Conciencia/fisiología , Retroalimentación , Hipocampo/fisiología , Humanos , Factores de Crecimiento Nervioso/metabolismo , Vías Nerviosas/fisiología , Neuronas/fisiología , Tálamo/fisiología
15.
Chem Biol Interact ; 260: 208-218, 2016 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-27717698

RESUMEN

Asparagus adscendens Roxb. commonly known as safed musli and belonging to the Liliaceae family is cultivated mainly in Asian countries. In traditional medicine, safed musli is recommended as nerve tonic and remedy for memory impairment. The present study was aimed to evaluate nootropic and antiamnesic activities of Asparagus adscendens extract (AAE) using in silico and in vivo approach. Phytoconstituents of A. adscendens root reported in literature were subjected to in silico prediction using PASS and Pharmaexpert. The radial arm maze and passive shock avoidance paradigm were employed to evaluate nootropic activity. Subsequently, the anti-amnesic activity was evaluated in scopolamine induced amnesia model. To elucidate the mechanism of nootropic activity, the effect of AAE on the activities of acetylcholinesterase and antioxidant enzymes in the cortex and hippocampus of mice were also evaluated. In silico activity spectrum for all of A. adscendens phytoconstituents exhibited excellent prediction score for nootropic activity. Pretreatment with AAE (50, 100 & 200 mg/kg, i.p.) for 15 days showed significant decrease in working memory error, reference memory error and retrieval latency in radial arm maze and decrease in step down latency in passive shock avoidance paradigm were observed. Further, AAE significantly reduced acetylcholinesterase and oxidative stress parameters in cortex and hippocampus of mice. Thus, in silico and in vivo results suggest that A. adscendens root may exert its nootropic activity through both anti-acetylcholinesterase and antioxidant activities.


Asunto(s)
Amnesia/tratamiento farmacológico , Amnesia/fisiopatología , Asparagaceae/química , Simulación por Computador , Fármacos Neuroprotectores/uso terapéutico , Extractos Vegetales/uso terapéutico , Raíces de Plantas/química , Acetilcolinesterasa/metabolismo , Animales , Reacción de Prevención/efectos de los fármacos , Biomarcadores/metabolismo , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Ratones , Actividad Motora/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Nitritos/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Extractos Vegetales/farmacología , Escopolamina , Análisis y Desempeño de Tareas , Pruebas de Toxicidad Aguda
16.
PLoS One ; 11(8): e0159823, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27483466

RESUMEN

We evaluated the neuropharmacological effects of Gongjin-Dan (GJD) on the memory impairment caused by scopolamine injection. BALB/c mice were orally treated with GJD (100, 200, or 400 mg/kg, daily) or tacrine (THA, 10 mg/kg) for 10 days, and scopolamine (2 mg/kg) was injected intraperitoneally. The radial arm maze and passive avoidance tests were performed to evaluate the animal's learning and memory. Scopolamine increased the task completing time, the number of total errors (reference and working memory error) in the radial arm maze task, and the latency time in the passive avoidance test, which were significantly ameliorated by treatment with GJD. The GJD treatment also attenuated the scopolamine-induced hyperactivation of acetylcholinesterase activity, and suppression of the expression of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) and their receptors in the hippocampus. These effects of GJD were supported by both the doublecortin (DCX)-positive staining and Nissl staining, which were used to measure hippocampal neurogenesis and atrophy, respectively. These findings strongly suggest that GJD exerts a potent anti-amnesic effect, and its underlying mechanism might involve the modulation of cholinergic activity.


Asunto(s)
Amnesia/inducido químicamente , Amnesia/tratamiento farmacológico , Hipocampo/efectos de los fármacos , Memoria/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Escopolamina , Acetilcolinesterasa/metabolismo , Amnesia/metabolismo , Amnesia/fisiopatología , Animales , Reacción de Prevención/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/análisis , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Proteína Doblecortina , Hipocampo/metabolismo , Hipocampo/fisiopatología , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Factor de Crecimiento Nervioso/análisis , Factor de Crecimiento Nervioso/metabolismo
17.
J Ethnopharmacol ; 190: 165-73, 2016 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-27267831

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Eclipta prostrata L. (Asteraceae) has been prescribed for whole body nourishment and nervine tonic in Asia. However, the effects of E. prostrata in learning and memory have not been fully explored. AIM OF THE STUDY: To scientifically elucidate the effects of E. prostrata on cognitive functions, we examined whether E. prostrata could ameliorate a cholinergic blockade-induced memory impairment, and we also investigated the effects of E. prostrata on the synaptic plasticity in the hippocampus. MATERIALS AND METHODS: Memory impairment was induced by scopolamine, a cholinergic muscarinic receptor antagonist. The anti-amnesic effects of the ethanolic extract of Eclipta prostrata L. (EEEP) were measured in mice by the passive avoidance, Y-maze and Morris water maze tasks. To test the effects of EEEP on synaptic plasticity, we measured long-term potentiation (LTP) in the hippocampus. We also studied several signaling molecules related to learning and memory, such as phosphorylated protein kinase B (Akt) or phosphorylated glycogen synthase kinase-3ß (GSK-3ß). RESULTS: In the passive avoidance task, EEEP (50 or 100mg/kg, p.o.) significantly ameliorated the shortened step-through latency induced by scopolamine. EEEP (100mg/kg, p.o.) also showed significant increase in alternation behavior during the Y-maze task. In the Morris water maze task, scopolamine-induced a decrease in both the swimming time within the target zone and the number of crossings where the platform had been placed were significantly reversed by EEEP (50 or 100mg/kg, p.o.). Moreover, EEEP (100µg/ml) significantly enhanced hippocampal LTP without affecting basal synaptic transmission. The administration of EEEP (100mg/kg) increased the phosphorylation levels of Akt and GSK-3ß in the hippocampal region. CONCLUSION: These results suggest that EEEP has memory-ameliorating activity against scopolamine-induced cognitive impairment and facilitates LTP in the hippocampus. This could be, at least in part, mediated by the activation of the Akt-GSK-3ß signaling pathway.


Asunto(s)
Amnesia/prevención & control , Conducta Animal/efectos de los fármacos , Trastornos del Conocimiento/prevención & control , Cognición/efectos de los fármacos , Eclipta/química , Etanol/química , Hipocampo/efectos de los fármacos , Memoria/efectos de los fármacos , Nootrópicos/farmacología , Extractos Vegetales/farmacología , Escopolamina , Solventes/química , Amnesia/inducido químicamente , Amnesia/fisiopatología , Amnesia/psicología , Animales , Trastornos del Conocimiento/inducido químicamente , Trastornos del Conocimiento/fisiopatología , Trastornos del Conocimiento/psicología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Hipocampo/metabolismo , Hipocampo/fisiopatología , Potenciación a Largo Plazo/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones Endogámicos ICR , Actividad Motora/efectos de los fármacos , Nootrópicos/aislamiento & purificación , Fosforilación , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tiempo de Reacción/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
18.
Biosci Biotechnol Biochem ; 80(1): 166-71, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26287580

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disease induced by cholinergic neuron damage or amyloid-beta aggregation in the basal forebrain region and resulting in cognitive disorder. We previously reported on the neuroprotective effects of Betula platyphylla bark (BPB) in an amyloid-beta-induced amnesic mouse model. In this study, we obtained a cognitive-enhancing compound by assessing results using a scopolamine-induced amnesic mouse model. Our results show that oral treatment of mice with BPB and betulin significantly ameliorated scopolamine-induced memory deficits in both passive avoidance and Y-maze tests. In the Morris water maze test, administration of BPB and betulin significantly improved memory and cognitive function indicating the formation of working and reference memories in treated mice. Moreover, betulin significantly increased glutathione content in mouse hippocampus, and the increase was greater than that from betulinic acid treatment. We conclude that BPB and its active component betulin have potential as therapeutic, cognitive enhancer in AD.


Asunto(s)
Amnesia/tratamiento farmacológico , Betula/química , Memoria/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Nootrópicos/farmacología , Triterpenos/farmacología , Administración Oral , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Amnesia/inducido químicamente , Amnesia/metabolismo , Amnesia/fisiopatología , Animales , Reacción de Prevención/efectos de los fármacos , Cognición/efectos de los fármacos , Modelos Animales de Enfermedad , Glutatión/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/fisiopatología , Humanos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Fármacos Neuroprotectores/aislamiento & purificación , Nootrópicos/aislamiento & purificación , Triterpenos Pentacíclicos , Corteza de la Planta/química , Extractos Vegetales/química , Escopolamina , Triterpenos/aislamiento & purificación , Ácido Betulínico
19.
Brain Nerve ; 67(12): 1481-94, 2015 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-26618762

RESUMEN

The anterior and mediodorsal thalamic nuclei form neuroanatomical networks supporting memory along with the mammillary body, medial temporal structures, prefrontal cortices and posterior cingulate cortex. In this review article, we discuss human diencephalic amnesic syndromes, including Wernicke-Korsakoff syndrome and amnesia associated with thalamic infarcts, and animal neuropsychological studies from a neuroanatomical network perspective. In addition, we suggest future research directions for understanding the functional roles of the anterior and mediodorsal thalamic nuclei in memory function based on findings from recent animal studies.


Asunto(s)
Amnesia/fisiopatología , Trastornos de la Memoria/fisiopatología , Memoria/fisiología , Enfermedades Talámicas/fisiopatología , Tálamo/anatomía & histología , Animales , Humanos , Pruebas Neuropsicológicas
20.
Neuroscience ; 258: 131-46, 2014 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-24215977

RESUMEN

Voluntary exercise (VEx) has profound effects on neural and behavioral plasticity, including recovery of CNS trauma and disease. However, the unique regional cortical adaption to VEx has not been elucidated. In a series of experiments, we first examined whether VEx would restore and retain neurotrophin levels in several cortical regions (frontal cortex [FC], retrosplenial cortex [RSC], occipital cortex [OC]) in an animal model (pyrithiamine-induced thiamine deficiency [PTD]) of the amnestic disorder Wernicke-Korsakoff syndrome. In addition, we assessed the time-dependent effect of VEx to rescue performance on a spontaneous alternation task. Following 2-weeks of VEx or stationary housing conditions (Stat), rats were behaviorally tested and brains were harvested either the day after VEx (24-h) or after an additional 2-week period (2-wk). In both control pair-fed (PF) rats and PTD rats, all neurotrophin levels (brain-derived neurotrophic factor [BDNF], nerve growth factor [NGF], and vascular endothelial growth factor) increased at the 24-h period after VEx in the FC and RSC, but not OC. Two-weeks following VEx, BDNF remained elevated in both FC and RSC, whereas NGF remained elevated in only the FC. Interestingly, VEx only recovered cognitive performance in amnestic rats when there was an additional 2-wk adaptation period after VEx. Given this unique temporal profile, Experiment 2 examined the cortical cytogenetic responses in all three cortical regions following a 2-wk adaptation period after VEx. In healthy (PF) rats, VEx increased the survival of progenitor cells in both the FC and RSC, but only increased oligodendrocyte precursor cells (OLPs) in the FC. Furthermore, VEx had a selective effect of only recovering OLPs in the FC in PTD rats. These data reveal the therapeutic potential of exercise to restore cortical plasticity in the amnestic brain, and that the FC is one of the most responsive cortical regions to VEx.


Asunto(s)
Amnesia/fisiopatología , Corteza Cerebral/fisiopatología , Actividad Motora/fisiología , Factores de Crecimiento Nervioso/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Supervivencia Celular , Análisis Citogenético , Lóbulo Frontal/fisiopatología , Vivienda para Animales , Masculino , Factor de Crecimiento Nervioso/metabolismo , Lóbulo Occipital/fisiopatología , Oligodendroglía/fisiología , Piritiamina , Ratas , Ratas Sprague-Dawley , Células Madre/fisiología , Deficiencia de Tiamina/fisiopatología , Factores de Tiempo , Factor A de Crecimiento Endotelial Vascular/metabolismo
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