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Tachykinin receptor 3 (TACR3) is a member of the tachykinin receptor family and falls within the rhodopsin subfamily. As a G protein-coupled receptor, it responds to neurokinin B (NKB), its high-affinity ligand. Dysfunctional TACR3 has been associated with pubertal failure and anxiety, yet the mechanisms underlying this remain unclear. Hence, we have investigated the relationship between TACR3 expression, anxiety, sex hormones, and synaptic plasticity in a rat model, which indicated that severe anxiety is linked to dampened TACR3 expression in the ventral hippocampus. TACR3 expression in female rats fluctuates during the estrous cycle, reflecting sensitivity to sex hormones. Indeed, in males, sexual development is associated with a substantial increase in hippocampal TACR3 expression, coinciding with elevated serum testosterone and a significant reduction in anxiety. TACR3 is predominantly expressed in the cell membrane, including the presynaptic compartment, and its modulation significantly influences synaptic activity. Inhibition of TACR3 activity provokes hyperactivation of CaMKII and enhanced AMPA receptor phosphorylation, associated with an increase in spine density. Using a multielectrode array, stronger cross-correlation of firing was evident among neurons following TACR3 inhibition, indicating enhanced connectivity. Deficient TACR3 activity in rats led to lower serum testosterone levels, as well as increased spine density and impaired long-term potentiation (LTP) in the dentate gyrus. Remarkably, aberrant expression of functional TACR3 in spines results in spine shrinkage and pruning, while expression of defective TACR3 increases spine density, size, and the magnitude of cross-correlation. The firing pattern in response to LTP induction was inadequate in neurons expressing defective TACR3, which could be rectified by treatment with testosterone. In conclusion, our study provides valuable insights into the intricate interplay between TACR3, sex hormones, anxiety, and synaptic plasticity. These findings highlight potential targets for therapeutic interventions to alleviate anxiety in individuals with TACR3 dysfunction and the implications of TACR3 in anxiety-related neural changes provide an avenue for future research in the field.
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Ansiedade , Hipocampo , Plasticidade Neuronal , Testosterona , Animais , Testosterona/metabolismo , Plasticidade Neuronal/fisiologia , Masculino , Ratos , Feminino , Ansiedade/metabolismo , Hipocampo/metabolismo , Receptores da Neurocinina-3/metabolismo , Neurônios/metabolismo , Potenciação de Longa Duração/fisiologia , Receptores de Taquicininas/metabolismo , Ratos Sprague-DawleyRESUMO
Neuropathic lysosomal storage disorders (LSDs) present with activated pro-inflammatory microglia. However, anti-inflammatory treatment failed to improve disease pathology. We characterise the mechanisms underlying microglia activation in Niemann-Pick disease type A (NPA). We establish that an NPA patient and the acid sphingomyelinase knockout (ASMko) mouse model show amoeboid microglia in neurodegeneration-prone areas. In vivo microglia ablation worsens disease progression in ASMko mice. We demonstrate the coexistence of different microglia phenotypes in ASMko brains that produce cytokines or counteract neuronal death by clearing myelin debris. Overloading microglial lysosomes through myelin debris accumulation and sphingomyelin build-up induces lysosomal damage and cathepsin B extracellular release by lysosomal exocytosis. Inhibition of cathepsin B prevents neuronal death and behavioural anomalies in ASMko mice. Similar microglia phenotypes occur in a Niemann-Pick disease type C mouse model and patient. Our results show a protective function for microglia in LSDs and how this is corrupted by lipid lysosomal overload. Data indicate cathepsin B as a key molecule mediating neurodegeneration, opening research pathways for therapeutic targeting of LSDs and other demyelinating diseases.
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Catepsina B/metabolismo , Microglia/patologia , Doença de Niemann-Pick Tipo A/patologia , Esfingomielina Fosfodiesterase/genética , Animais , Linhagem Celular , Pré-Escolar , Modelos Animais de Doenças , Progressão da Doença , Humanos , Recém-Nascido , Lisossomos/metabolismo , Lisossomos/patologia , Camundongos , Camundongos Knockout , Microglia/metabolismo , Doença de Niemann-Pick Tipo A/genética , Fenótipo , Esfingomielinas/metabolismoRESUMO
The accumulation of relatively higher dose of zinc oxide nanoparticles in brain was reported to produce neurotoxicity. Indeed, nanoparticles have a high ability to penetrate biological membranes and be uptaken by cells, which may cause cell disorders and physiological dysfunctions. The aim of the current study was to evaluate, whether oral administration of saffron extract, in rats, can protect from neurotoxicity and behavioural disturbances induced by chronic administration of ZnO-NPs. Daily oral administration of ZnO-NPs was performed for 21 consecutive days to induce oxidative stress-like situation. Then after the saffron extract was concomitantly administrated in several rat groups to overcome the nanotoxicological effect induced by ZnO-NPs. In the frontal cortex, the hippocampus and the cerebellum, ZnO-NPs induced a H2 O2 -oxydative stress-like effect reflected in reduced enzymatic activities of catalase, superoxide dismutase and glutathione S-transferase, and decreased acetylcholinesterase activity. In addition, increased levels of proinflammatory interleukins IL-6 and IL-1-⺠occurred in the hippocampus, reveal the existence of brain inflammation. The concomitant administration of saffron extract to animals exposed to ZnO-NPs prevented the enhanced anxiety-related to the behaviour in the elevated plus-maze test, the open field test and preserved spatial learning abilities in the Morris water maze. Moreover, animals exposed to ZnO-NPs and saffron showed abnormal activity of several antioxidant enzymes as well as acetylcholinesterase activity, an effect that may underly the preserved anxiety-like behaviour and spatial learning abilities observed in these animals. Saffron extract has a potential beneficial therapeutic effect: antioxidant, anti-inflammatory and neuroprotective agent.
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Disfunção Cognitiva , Crocus , Nanopartículas Metálicas , Óxido de Zinco , Ratos , Animais , Antioxidantes/metabolismo , Zinco/farmacologia , Acetilcolinesterase/metabolismo , Acetilcolinesterase/farmacologia , Crocus/metabolismo , Óxido de Zinco/toxicidade , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo , Administração OralRESUMO
Phosphatase and tensin homolog on chromosome 10 (PTEN) is a tumor suppressor and autism-associated gene that exerts an important influence over neuronal structure and function during development. In addition, it participates in synaptic plasticity processes in adulthood. As an attempt to assess synaptic and developmental mechanisms by which PTEN can modulate cognitive function, we studied the consequences of 2 different genetic manipulations in mice: presence of additional genomic copies of the Pten gene (Ptentg) and knock-in of a truncated Pten gene lacking its PDZ motif (Pten-ΔPDZ), which is required for interaction with synaptic proteins. Ptentg mice exhibit substantial microcephaly, structural hypoconnectivity, enhanced synaptic depression at cortico-amygdala synapses, reduced anxiety, and intensified social interactions. In contrast, Pten-ΔPDZ mice have a much more restricted phenotype, with normal synaptic connectivity, but impaired synaptic depression at cortico-amygdala synapses and virtually abolished social interactions. These results suggest that synaptic actions of PTEN in the amygdala contribute to specific behavioral traits, such as sociability. Also, PTEN appears to function as a bidirectional rheostat in the amygdala: reduction in PTEN activity at synapses is associated with less sociability, whereas enhanced PTEN activity accompanies hypersocial behavior.
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Tonsila do Cerebelo/fisiologia , Córtex Cerebral/fisiologia , Plasticidade Neuronal , PTEN Fosfo-Hidrolase/fisiologia , Comportamento Social , Tonsila do Cerebelo/ultraestrutura , Animais , Feminino , Hipocampo/fisiologia , Masculino , Memória/fisiologia , Camundongos Transgênicos , Sinapses/fisiologia , Sinapses/ultraestruturaRESUMO
The prefrontal cortex, and especially the Dorsolateral Prefrontal Cortex (DLPFC), plays an inhibitory role in the regulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis under stressful situations. Moreover, recent evidence suggests that a sustained DLPFC activation is associated with adaptive stress regulation in anticipation of a stressful event, leading to a reduced stress-induced amygdala response, and facilitating the confrontation with the stressor. However, studies using experimental manipulation of the activity of the DLPFC before a stressor are scarce, and more research is needed to understand the specific role of this brain area in the stress-induced physiological response. This pre-registered study investigated the effect on stress regulation of a single excitatory high frequency (versus sham) repetitive transcranial magnetic stimulation (HF-rTMS) session over the left DLPFC applied before the Trier Social Stress Test in 75 healthy young women (M = 21.05, SD = 2.60). Heart rate variability (HRV) and salivary cortisol were assessed throughout the experimental protocol. The active HF-rTMS and the sham group showed a similar cognitive appraisal of the stress task. No differences in HRV were observed during both the anticipation and the actual confrontation with the stress task and therefore, our results did not reflect DLPFC-related adaptive anticipatory adjustments. Importantly, participants in the active HF-rTMS group showed a lower cortisol response to stress. The effect of left prefrontal HF-rTMS on the stress system provides further critical experimental evidence for the inhibitory role played by the DLPFC in the regulation of the HPA axis.
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Frequência Cardíaca/fisiologia , Hidrocortisona/metabolismo , Córtex Pré-Frontal/fisiologia , Estresse Fisiológico , Estimulação Magnética Transcraniana/métodos , Adolescente , Adulto , Feminino , Frequência Cardíaca/efeitos da radiação , Humanos , Hidrocortisona/análise , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipotálamo-Hipofisário/efeitos da radiação , Campos Magnéticos , Sistema Hipófise-Suprarrenal/metabolismo , Sistema Hipófise-Suprarrenal/fisiopatologia , Sistema Hipófise-Suprarrenal/efeitos da radiação , Córtex Pré-Frontal/efeitos da radiação , Saliva/química , Saliva/metabolismo , Estresse Fisiológico/fisiologia , Estresse Fisiológico/efeitos da radiação , Estresse Psicológico/etiologia , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Adulto JovemRESUMO
Post-traumatic stress disorder (PTSD) occurs after exposure to traumatic situations and it is characterized by cognitive deficits that include impaired explicit memory. The neurobiological bases of such PTSD-associated memory alterations are yet to be elucidated and no satisfactory treatment for them exists. To address this issue, we first studied whether a single exposure of young adult rats (60 days) to immobilization on boards (IMO), a putative model of PTSD, produces long-term behavioral effects (2-8 days) similar to those found in PTSD patients. Subsequently, we investigated whether the administration of the TrkB agonist 7,8-dihydroxyflavone (DHF) 8 h after stress (therapeutic window) ameliorated the PTSD-like effect of IMO and the associated changes in synaptic plasticity. A single IMO exposure induced a spatial memory impairment similar to that found in other animal models of PTSD or in PTSD patients. IMO also increased spine density and long-term potentiation (LTP) in the CA3-CA1 pathway. Significantly, DHF reverted both spatial memory impairment and the increase in LTP, while it produced no effect in the controls. These data provide novel insights into the possible neurobiological substrate for explicit memory impairment in PTSD patients, supporting the idea that the activation of the BDNF/TrkB pathway fulfils a protective role after severe stress. Administration of DHF in the aftermath of a traumatic experience might be relevant to prevent its long-term consequences. © 2016 Wiley Periodicals, Inc.
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Flavonas/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Transtornos da Memória/prevenção & controle , Psicotrópicos/farmacologia , Receptor trkB/agonistas , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Animais , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/patologia , Região CA1 Hipocampal/fisiopatologia , Região CA3 Hipocampal/efeitos dos fármacos , Região CA3 Hipocampal/patologia , Região CA3 Hipocampal/fisiopatologia , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/patologia , Espinhas Dendríticas/fisiologia , Modelos Animais de Doenças , Potenciação de Longa Duração/fisiologia , Masculino , Transtornos da Memória/etiologia , Transtornos da Memória/patologia , Transtornos da Memória/fisiopatologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptor trkB/metabolismo , Restrição Física , Memória Espacial/efeitos dos fármacos , Memória Espacial/fisiologia , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/patologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/patologia , Estresse Psicológico/fisiopatologia , Técnicas de Cultura de TecidosRESUMO
Cell adhesion molecules and downstream growth factor-dependent signaling are critical for brain development and synaptic plasticity, and they have been linked to cognitive function in adult animals. We have previously developed a mimetic peptide (FGL) from the neural cell adhesion molecule (NCAM) that enhances spatial learning and memory in rats. We have now investigated the cellular and molecular basis of this cognitive enhancement, using biochemical, morphological, electrophysiological, and behavioral analyses. We have found that FGL triggers a long-lasting enhancement of synaptic transmission in hippocampal CA1 neurons. This effect is mediated by a facilitated synaptic delivery of AMPA receptors, which is accompanied by enhanced NMDA receptor-dependent long-term potentiation (LTP). Both LTP and cognitive enhancement are mediated by an initial PKC activation, which is followed by persistent CaMKII activation. These results provide a mechanistic link between facilitation of AMPA receptor synaptic delivery and improved hippocampal-dependent learning, induced by a pharmacological cognitive enhancer.
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Cognição/fisiologia , Hipocampo/citologia , Potenciação de Longa Duração/efeitos dos fármacos , Moléculas de Adesão de Célula Nervosa/farmacologia , Neurônios/efeitos dos fármacos , Receptores de AMPA/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Análise de Variância , Animais , Western Blotting , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Ensaio de Imunoadsorção Enzimática , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Microscopia Eletrônica , Microscopia de Fluorescência , Neurônios/fisiologia , Técnicas de Patch-Clamp , Fosforilação , Proteína Quinase C/metabolismo , Ratos , Ratos Wistar , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transmissão Sináptica/fisiologiaRESUMO
Fluoxetine (FLX) is prescribed to treat depression and anxiety in adolescent patients. However, FLX has anxiogenic effects during the acute phase of treatment, and caution has been raised due to increased suicidal thinking and behavior. Herein, we sought to study in adolescent (35-day-old) male rats, the effects of short-term FLX treatment (10 mg/kg/day, i.p. for 3-4 days) on hypothalamic-pituitary-adrenal axis activity, serotonin (5-hidroxytriptamine, 5-HT) transporter (SERT) mRNA expression in the dorsal raphe nucleus (DRN), energy balance-related variables and behavioral profiles in the holeboard. Our results revealed that daily FLX administration increased plasma corticosterone (B) concentrations without affecting basal gene expression of corticotrophin releasing hormone in the hypothalamic paraventricular nucleus (PVN) nor of pro-opiomelanocortin in the anterior pituitary. However, FLX had significant effects increasing the mRNA expression of PVN arginine vasopressin (AVP) and reducing SERT mRNA levels in the dorsolateral subdivision of the DRN. In the holeboard, FLX-induced anxiety/emotionality-like behaviors. As expected, FLX treatment was endowed with anorectic effects and reduced body weight gain. Altogether, our study shows that short-term FLX treatment results in physiological, neuroendocrine and behavioral stress-like effects in adolescent male rats. More importantly, considering that the AVP- and 5-HTergic systems: (1) are intimately involved in regulation of the stress response; (2) are regulated by sex hormones and (3) are related to regulation of aggressive behaviors, our results highlight the potential significance of these systems mediating the anxiogenic/emotionality/stress-like responses of adolescent male rats to short-term FLX treatment.
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Ansiedade/induzido quimicamente , Comportamento Animal/efeitos dos fármacos , Fluoxetina/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Animais , Ansiedade/metabolismo , Corticosterona/sangue , Núcleo Dorsal da Rafe/efeitos dos fármacos , Núcleo Dorsal da Rafe/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismoRESUMO
[This corrects the article DOI: 10.1371/journal.pone.0283169.].
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Social isolation in adulthood is a psychosocial stressor that can result in endocrinological and behavioral alterations in different species. In rodents, controversial results have been obtained in fear conditioning after social isolation at adulthood, while neural substrates underlying these differences are largely unknown. Neural cell adhesion molecule (NCAM) and its polysialylated form (PSA-NCAM) are prominent modulators of synaptic plasticity underlying memory processes in many tasks, including fear conditioning. In this study, we used adult female Octodon degus to investigate the effects of long-term social isolation on contextual and cued fear conditioning, and the possible modulation of the synaptic levels of NCAM and PSA-NCAM in the hippocampus. After 6½ months of social isolation, adult female degus showed a normal auditory-cued fear memory, but a deficit in contextual fear memory, a hippocampal dependent task. Subsequently, we observed reduced hippocampal synaptic levels of PSA-NCAM in isolated compared to grouped-housed female degus. No significant differences were found between experimental groups in hippocampal levels of the three main isoforms of NCAM (NCAM180, NCAM140 and NCAM120). Interestingly, social isolation reduced the volume of the hippocampal CA1 subfield, without affecting the volume of the CA3 subregion or the total hippocampus. Moreover, attenuated body weight gain and reduced number of granulocytes were detected in isolated animals. Our findings indicate for the first time, that long-term social isolation of adult female animals induces a specific shrinkage of CA1 and a decrease in synaptic levels of PSA-NCAM in the hippocampus. These effects may be related to the deficit in contextual fear memory observed in isolated female degus.
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Região CA1 Hipocampal/patologia , Transtornos Cognitivos/patologia , Isolamento Social , Animais , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/fisiopatologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/fisiopatologia , Condicionamento Psicológico/fisiologia , Medo/fisiologia , Feminino , Memória/fisiologia , Moléculas de Adesão de Célula Nervosa/metabolismo , Octodon , Tamanho do ÓrgãoRESUMO
Aging is associated with a decline in cognitive abilities, mainly in memory and executive functioning. A similar but premature deterioration in cognitive capacities is the hallmark of mild cognitive impairment, Alzeimer's disease and dementia. The biochemical mechanisms that cause these neurodegenerative disorders are poorly understood. However, some evidence suggests that insufficient dietary intakes of some phospholipids could impact on brain function and increase the risk of future cognitive impairment and dementia. We evaluated the cognitive and biochemical effects of supplementation with a milk fat globule membrane (MFGM) concentrate in aged rats. We observed that, compared to control animals, MFGM supplemented rats showed enhanced spatial working memory, but both groups exhibited similar reference spatial learning and emotional memory abilities. No significant differences between BDNF levels in the hippocampus and frontal cortex of treated rats as compared to controls were found. The nootropic effects observed were accompanied by significant changes in the lipid composition of synaptic membranes. MFGM supplementation increased the levels of EPA and DHA acids as well as the plasmalogens content in the synaptosomes isolated from the hippocampus (Synapt-HP) and the frontal cortex (Synapt-FC). In addition enhanced levels of phosphatidyl serine (PS), particularly PS(18:1/18:1), and phosphatidyl inositol (PI) molecular species were observed in Synapt-HP and Synapt-FC of treated animals.Lipidomic analysis also revealed greater concentration of phosphatidyl ethanolamine (PE) molecular species containing very long-chain fatty acids and PE plasmenyls in Synapt-HP as well as an increase of the SM content in Synapt-FC from the MFGM group. Although further studies are needed to confirm the underlying mechanism (individual or synergistic), these results suggest that MFGM supplementation could be employed as a dietary implement to restore the proper cerebral concentration of some bioactive lipids and prevent or slow the progression of age-related cognitive impairment.
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Disfunção Cognitiva , Demência , Animais , Ratos , Sinaptossomos , Lipidômica , Suplementos Nutricionais , Disfunção Cognitiva/prevenção & controleRESUMO
Introduction: Prolonged social isolation is a form of passive chronic stress that has consequences on human and animal behavior. The present study was undertaken to elucidate whether the long-term isolation would precipitate age-related changes in anxiety and spatial learning and memory in degus. Methods: We investigated the effects of long-term social isolation on anxiety levels in the light-dark test, and spatial orientation abilities in the Barnes maze. Middle-aged female Octodon degus were allocated to either group-housed (3 animals per cage) or individually-housed for 5 months. Results: Under this experimental condition, there were no significant group differences in the anxiety level tested in the light-dark test and in the motivation to escape from the Barnes maze. There were no significant differences in cortisol levels between individually- and group-housed animals. On the last acquisition training day of spatial learning, individually- housed animals had a significantly higher number of correct responses and a smaller number of reference and working memory errors than the group-housed animals. In addition, isolated animals showed a tendency for reference and working memory impairment on the retention trial, while group-housed degus showed improvement in these parameters. Discussion and conclusion: The present study indicates that prolonged social isolation during adulthood in female degus has a dual effect on spatial orientation. Specifically, it results in a significant improvement in acquisition skills but a slight impairment in memory retention. The obtained cognitive changes were not accompanied by modification in anxiety and cortisol levels.
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Introduction: Loneliness is a distressful feeling that can affect mental and physical health, particularly among older adults. Cortisol, the primary hormone of the Hypothalamic-Pituitary-Adrenal axis (HPA-axis), may act as a biological transducer through which loneliness affects health. While most previous studies have evaluated the association between loneliness, as a unidimensional construct, and diurnal cortisol pattern, no research has examined this relationship discriminating between social and emotional loneliness in older adults. As sex differences in the negative mental health outcomes of loneliness have been reported, we also investigated whether diurnal cortisol indices and loneliness associations occur in a sex-specific manner. Methods: We analyzed the diurnal cortisol- pattern in 142 community-dwelling, non-depressed, Caucasian older adults (55,6% female) aged 60-90. Social and emotional (family and romantic) loneliness scores were assessed using the Spanish version of the Social and Emotional Loneliness Scale for Adults (SELSA). Five salivary cortisol samples were used to capture key features of the diurnal cortisol pattern, including: awakening and bedtime cortisol levels, awakening response (CAR), post-awakening cortisol output (post-awakening cortisol [i.e., the area under the curve with reference to the ground: AUCG]), total diurnal cortisol release (AUCG), and diurnal cortisol slope (DCS). Results: After controlling for sociodemographic variables, the hierarchical linear multiple regression analyses revealed that in male older adults, higher scores on social and family loneliness were associated with elevated awakening cortisol levels, total diurnal cortisol output, and a steeper diurnal cortisol slope (DCS). However, these associations were not observed in female older adults. In addition, feelings of romantic loneliness were positively associated with bedtime cortisol levels and AUCG in older males. Multilevel growth curve modeling showed that experiencing more social and emotional loneliness predicted higher diurnal cortisol output throughout the day in older male adults. Discussion: The presence of sex differences in the relationship between cortisol indices and loneliness among older adults holds particular significance for diagnostic and screening procedures. Combining loneliness scales as screening tools with diurnal cortisol measures has the potential to be an effective and cost-efficient approach in identifying higher-risk individuals at early stages.
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INTRODUCTION: The main objective of the study will be to evaluate the effects of two widely used standardized mindfulness-based programs [Mindfulness-Based Stress Reduction (MBSR) and Compassion Cultivation Training (CCT)], on epigenetic, neurobiological, psychological, and physiological variables. METHODS: The programs will be offered in an intensive retreat format in a general population sample of healthy volunteer adults. During a 7-day retreat, participants will receive MBSR and CCT in a crossover design where participants complete both programs in random order. After finishing their first 3-day training with one of the two programs, participants will be assigned to the second 3-day training with the second program. The effects of the MBSR and CCT programs, and their combination, will be measured by epigenetic changes (i.e., DNA methylation biomarkers), neurobiological and psychophysiological measures (i.e., EEG resting state, EKG, respiration patterns, and diurnal cortisol slopes), self-report questionnaires belonging to different psychological domains (i.e., mindfulness, compassion, well-being, distress, and general functioning), and stress tasks (i.e., an Arithmetic Stress Test and the retrieval of negative autobiographical memories). These measures will be collected from both groups on the mornings of day 1 (pre-program), day 4 (after finishing the first program and before beginning the second program), and day 7 (post-second program). We will conduct a 3-month and a 12-month follow-up using only the set of self-report measures. DISCUSSION: This study aims to shed light on the neurobiological and psychological mechanisms linked to meditation and compassion in the general population. The protocol was registered at clinicaltrials.gov (Identifier: NCT05516355; August 23, 2022).
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Meditação , Atenção Plena , Humanos , Adulto , Atenção Plena/métodos , Empatia , Hidrocortisona , Meditação/métodos , Eletroencefalografia , Estresse Psicológico/psicologia , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
In this work, we tested the hypothesis that the development of dementia in individuals with type 2 diabetes (T2DM) requires a genetic background of predisposition to neurodegenerative disease. As a proof of concept, we induced T2DM in middle-aged hAPP NL/F mice, a preclinical model of Alzheimer's disease. We show that T2DM produces more severe behavioral, electrophysiological, and structural alterations in these mice compared with wild-type mice. Mechanistically, the deficits are not paralleled by higher levels of toxic forms of Aß or by neuroinflammation but by a reduction in γ-secretase activity, lower levels of synaptic proteins, and by increased phosphorylation of tau. RNA-seq analysis of the cerebral cortex of hAPP NL/F and wild-type mice suggests that the former could be more susceptible to T2DM because of defects in trans-membrane transport. The results of this work, on the one hand, confirm the importance of the genetic background in the severity of the cognitive disorders in individuals with T2DM and, on the other hand, suggest, among the involved mechanisms, the inhibition of γ-secretase activity.
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Doença de Alzheimer , Disfunção Cognitiva , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Doenças Neurodegenerativas , Camundongos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Camundongos Transgênicos , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Suscetibilidade a DoençasRESUMO
The coronavirus disease 2019 (COVID-19) pandemic led to various government-imposed limitations on social interaction and strict home confinement. Such involuntary social-distancing policies can exacerbate feelings of loneliness and alter emotional well-being. Dysregulation of the hypothalamic-pituitary-adrenocortical (HPA) axis is a potential mechanism for loneliness' deleterious health effects. In this study, we explored whether pre-pandemic diurnal cortisol output (AUC G ), a measure of HPA axis function, may predict the propensity to changes in loneliness during long-term COVID-19 home confinement and if extraversion would moderate this relationship. This association has been explored by analysing the impact of COVID-19 pandemic and strict home confinement on social and emotional loneliness in 45 Spanish young adults. Diurnal cortisol levels were measured from five saliva samples obtained across a day just before the pandemic, and data about participants' perceived loneliness, empathic state, extraversion, and prospective volunteering were obtained both before and during the confinement. Participants' social and family loneliness increased during long-term strict home confinement, while prospective volunteering tendencies and extraversion decreased. Importantly, after adjusting for relevant confounders, moderation analyses revealed that in young adults with high pre-pandemic extraversion, a higher AUC G predicted a larger increase in social loneliness during confinement, while in individuals with low extraversion, AUC G was negatively related to change in loneliness. Our findings highlight the utility of pre-pandemic diurnal cortisol output in predicting the social impact of COVID-19 home confinement, presenting this hormone as a potential biomarker for a priori identification of at-risk groups during public health crises.
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OBJECTIVE: This study aimed to generate updated normative data for commonly used tests in neuropsychological assessment applied to older monolingual Spanish-speaking adults: Verbal fluency tests, the Trail Making Test (TMT), and the Rey-Osterrieth complex figure test (ROCF). METHOD: To obtain normative data, 382 cognitively healthy 60- to 90-year-old Spanish monolingual participants from the Autonomous Community of Madrid (Spain) with 0-22 years education were assessed using an overlapping interval strategy that involved cell and midpoint techniques, and that assessed the influence of age, education, and sex. RESULTS: Age and education were associated with the scores in the verbal fluency tests, TMT, and ROCF, whereas sex only significantly affected the TMT results. Age-adjusted scaled scores (SSA) based on percentile ranks were also converted into age-education scaled scores (SSAE) using a linear regression model. In addition, tables with the relevant adjustments for sex are provided for TMT-A and TMT-B. CONCLUSIONS: Thus, this study provides updated, uniform normative data for widely used neuropsychological tests on older Spanish adults. The normative procedure followed helps to make consistent comparisons when using these neuropsychological tests, which will improve the interpretation of the data obtained when these tools are employed, reducing the risk of misdiagnosing cognitive impairment in older adults.
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Disfunção Cognitiva , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/diagnóstico , Escolaridade , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Valores de Referência , Teste de Sequência AlfanuméricaRESUMO
The aim of this study was to establish normative data for the Spanish version of the California Verbal Learning Test, the Test de Aprendizaje Verbal España-Complutense (TAVEC). Through different subtests, the TAVEC allows verbal learning and episodic memory to be evaluated, an assessment that was carried out on a sample of 382 cognitive healthy Spanish individuals aged 60-90 years old. Unlike the participant's educational level, their age and sex significantly influenced performance in the TAVEC. We provide tables that allow the scaled scores obtained with this test to be adjusted for age and other tables with the relevant adjustments for sex. The normative data obtained in this study will help more precisely interpret the performance of older Spanish adults in the TAVEC, enhancing the utility of this neuropsychological test to evaluate verbal learning and episodic memory in clinical settings and in relation to healthy aging. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
Assuntos
Envelhecimento Saudável , Memória Episódica , Idoso , Idoso de 80 Anos ou mais , Humanos , Testes de Memória e Aprendizagem , Pessoa de Meia-Idade , Testes Neuropsicológicos , Valores de Referência , Aprendizagem VerbalRESUMO
AIM: The Memory Failures of Everyday (MFE) is a widely used instrument for assessing memory failure. The aim of the study was to analyze the MFE items using the Rasch model in a sample of cognitively older adults in Spain. METHODS: A cross-sectional validation study in a sample of 214 healthy people aged ≥60 years who used centers for older people in Madrid (Spain). The MFE for the assessment of memory complaints was used. The following properties of the Rasch model were assessed: data fit, reliability, unidimensionality, local dependence and lack of differential item functioning by gender, age and marital status. RESULTS: The MFE showed a good fit to the Rasch model (χ2 (140) = 160.2; P = 0.116) and high reliability (person separation index = 0.808). The questionnaire was unidimensional (6.54% t-test; IC binomial = 0.036-0.095). The items showed lack of local dependence between them and differential item functioning. The MFE scores were transformed into linear interval scores with a median of 44.31 and an observed range of 17.9-89.2 (theoretical range: 0-100). CONCLUSIONS: The MFE is a unidimensional, reliable instrument to assess memory complaints in cognitively healthy older adults in Spain, with usefulness in clinical research and practice. The construct validity of the MFE linear score could not be fully confirmed and this deserves further investigation. Geriatr Gerontol Int 2022; 22: 332-337.