RESUMO
ABSTRACT Mild cognitive impairment (MCI) is an interstitial state between normal aging and dementia. Objective: In this study, we investigated working memory (WM) profiles of MCI patients using the Cambridge Neuropsychological Test Automated Battery (CANTAB). We also examined the diagnostic accuracy and possible associated factors as secondary outcomes of the study. Methods: We conducted an electronic search on EMBASE, PubMed, and ScienceDirect databases. Studies with MCI participants and using CANTAB battery subtests for the assessment of WM were included. Meta-analysis was conducted using the CMA2 software. Results: Out of 1537 records, 14 studies were covered in this systematic review, and 7 of them were included in the meta-analysis. There was a significant difference between MCI patients and healthy controls in spatial working memory (SWM) (SDM: 0.535; 95%CI 11-96; p-value=0.014), spatial span (SSP) (SDM: 0.649 95%CI 0.297-0.100; p-value<0.01), and rapid visual information processing (RVP) (SDM: 0.52; 95%CI 0.386-0.654; p-value<0.01). WM function of MCI patients was associated with the cerebrospinal fluid (CSF) levels of tau-protein and amyloid-beta (Aβ). Conclusions: WM is an impaired cognitive domain in MCI. CANTAB WM subtests including SSP, SWM, and RVP are accurate enough to be used as a proper assessment tool for the diagnosis of MCI in clinical settings. Tau-protein and Aβ are associated with lower WM scores in MCI patients; however, sex, age, psychiatric disorders, apolipoprotein 4 allele, and functional activity scores cannot affect WM.
RESUMO O comprometimento cognitivo leve (CCL) é um estado intersticial entre o envelhecimento normal e a demência. Objetivo: Neste estudo, investigamos os perfis de memória de trabalho (MT) de pacientes com CCL usando a bateria automatizada de testes neuropsicológicos de Cambridge (Cambridge Neuropsychological Test Automated Battery - CANTAB). Também examinamos a acurácia diagnóstica e possíveis fatores associados como desfechos secundários do estudo. Métodos: Foi realizada uma busca eletrônica nas bases de dados EMBASE, PubMed e ScienceDirect. Foram incluídos estudos com participantes com CCL e utilizando subtestes da bateria CANTAB para avaliação da MT. A meta-análise foi realizada usando o software CMA2. Resultados: Dos 1.537 registros, esta revisão sistemática abordou 14 estudos, e 7 deles foram incluídos na meta-análise. Houve uma diferença significativa entre pacientes com CCL e controles saudáveis na memória de trabalho espacial (MTE) (DPM: 0,535; IC95% 11-96; valor p=0,014), spatial span (SSP) (SDM: 0,649; IC95% 0,297-0,100; valor p<0,01) e processamento rápido de informação visual (PRV) (DPM: 0,52; IC95% 0,386-0,654; valor p<0,01). A MT de pacientes com CCL foi associada com os níveis de proteína tau e beta-amiloide (Aβ) no líquido cefalorraquidiano (CSF). Conclusões: A MT é um domínio cognitivo prejudicado no CCL. Os subtestes CANTAB WM, incluindo SSP, MTE e PRV, são precisos o suficiente para serem usados como uma ferramenta de avaliação adequada para o diagnóstico de CCL em ambientes clínicos. A proteína Tau e Aβ estão associadas a pontuações de MT mais baixas em pacientes com CCL; entretanto, sexo, idade, transtornos psiquiátricos, alelo da apolipoproteína 4 e escores de atividade funcional não podem afetar a MT.
Assuntos
HumanosRESUMO
PURPOSE: To evaluate the effects of PHA-543613 (α7-nAChR agonist) and galantamine (acetylcholinesterase inhibitor (AChEI)) on recognition memory and neurovascular coupling (NVC) response in beta-amyloid (Aβ) 25-35-treated mice. METHODS: PHA-543613 (1 mg/kg, i.p.), and galantamine (3 mg/kg, s.c.), effects were tested in Aβ25-35 mice model of AD. α7-nAChR antagonist, methyllycaconitine (MLA) (1 mg/kg, i.p.), was used for evaluation of receptor blockade effects. Recognition memory in animals was assessed by the novel object recognition (NOR) task. NVC response was analyzed by laser-doppler flow meter in barrel cortex by whisker stimulation method. RESULTS: Both, PHA-543613 and galantamine improve recognition memory in Aβ-treated animals. However, the advantageous effects of PHA-543613 were significantly higher than galantamine. Also, pretreatment with MLA reversed both galantamine and PHA-543613 effects on NOR. Impaired NVC response in AD animals was improved by PHA-543613 and galantamine. However, MLA pretreatment disrupts this function. CONCLUSION: Activation of α7-nAChR improved recognition memory possible through enhancement of neurovascular response in Alzheimer's disease in animals.