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1.
Hypertension ; 79(1): 218-229, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34775786

RESUMO

There are inconsistent results on the impacts of controlling blood pressure (BP) on the risk of dementia. We investigated the association between BP and risk of dementia subtypes by antihypertensive treatment and comorbidities. Using the Korean National Health Insurance Service-Health Screening Database from 2009 to 2012, a total of 4 522 447 adults aged 60+ years without a history of dementia were analyzed and followed up for a mean of 5.4 years. Individuals were classified according to their baseline systolic BP (SBP) and diastolic BP; SBP 130 to <140 mm Hg and diastolic BP 80 to <90 mm Hg were used as reference groups. The risk of overall dementia and probable Alzheimer disease was significantly higher in the SBP≥160 and lower SBP groups. These U-shaped associations were consistent regardless of antihypertensive use or comorbidities. The risk of probable vascular dementia (VaD) was not higher among lower SBP groups and increased gradually as SBP increased. Although there was a linear association between SBP and the risk of probable VaD in individuals not taking antihypertensives or without comorbidities, there was a U-shaped association in individuals taking antihypertensives or with comorbidities. Patterns of association between diastolic BP and risk of probable Alzheimer disease or probable VaD were similar to those with SBP, except for the risk of probable VaD in individuals taking antihypertensives. In conclusion, risks of probable Alzheimer disease and probable VaD were different among lower BP groups. Although the risk of dementia appears higher in people with lower BP receiving antihypertensives, this finding may be affected by comorbidities.


Assuntos
Pressão Sanguínea/fisiologia , Demência/epidemiologia , Hipertensão/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/fisiopatologia , Anti-Hipertensivos/uso terapêutico , Comorbidade , Demência/fisiopatologia , Demência Vascular/epidemiologia , Demência Vascular/fisiopatologia , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Incidência , Masculino , Pessoa de Meia-Idade , Risco
2.
Brain Res ; 1776: 147750, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896332

RESUMO

INTRODUCTION: The incidence rate of senile dementia is rising, and there is no definite cure for it yet. Cell therapy, as a new investigational approach, has shown promising results. Hair bulges with abundant easily accessible neural stem cells permit autologous implantation in irreversible neurodegenerative disorders. METHODS: Fifty rats were randomly divided into 5 groups of control, sham-operation, two-common carotid vessel-occlusion rats that received vehicle (2VO + V), 2VO rats that received 1 × 106 epidermal stem cells (2VO + ESC1), and 2VO rats that received 2.5 × 106 epidermal stem cells (2VO + ESC2) in 300 µl PBS intravenously on days 4, 9, and 14 after surgery. The epidermal neural crest stem cells (EPI-NCSCs) were isolated from hair follicles of rat whiskers. The open-field, passive avoidance, and Morris water maze were used as behavioral tests. The basal-synaptic transmission, long-term potentiation (LTP), and short-term synaptic plasticity were evaluated by field-potential recording of the CA1 hippocampal area. RESULTS: 30 days after the first transplantation in the 2VO + ESC1 group, functional recovery was prominent in anxiety and fear memory compared to the 2VO + ESC2 group, while LTP induction was recovered in both groups of grafted animals without improvement in basal synaptic transmission. These positive recoveries may be related to the release of different neurotrophic factors from grafted cells that can stimulate endogenous neurogenesis and synaptic plasticity. CONCLUSIONS: Our results showed that EPI-NCSCs implantation could rescue LTP and cognitive disability in 2VO rats, while transplantation of 1 million cells showed better performance relative to 2.5 million cells.


Assuntos
Demência Vascular/terapia , Crista Neural/citologia , Células-Tronco Neurais/transplante , Neuroproteção/fisiologia , Transplante de Células-Tronco/métodos , Animais , Aprendizagem da Esquiva/fisiologia , Demência Vascular/fisiopatologia , Modelos Animais de Doenças , Aprendizagem em Labirinto/fisiologia , Ratos , Transmissão Sináptica/fisiologia
3.
J Alzheimers Dis ; 85(4): 1819-1833, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34958038

RESUMO

BACKGROUND: Understanding how the age of dementia symptom onset affects the longitudinal course of dementia can assist with prognosis and care planning. OBJECTIVE: To synthesize evidence regarding the relationship of age of symptom onset with the longitudinal course of sporadic Alzheimer's disease (AD), vascular dementia (VaD), and frontotemporal dementia (FTD). METHODS: We searched Medline, CINAHL, Embase, PsycINFO, PubMed, and Scopus for longitudinal studies that examined the impact of sporadic AD, VaD, or FTD symptom onset age on measures of cognition, function, or behavioral symptoms. Studies that examined age at diagnosis only were excluded. Quantitative meta-analysis was conducted where studies reported sufficient data for pooling. RESULTS: Thirty studies met all inclusion criteria (people with AD (n = 26), FTD (n = 4)) though no studies examined VaD. Earlier onset of AD was associated with more rapid annual cognitive decline (estimate = -0.07; 95% CI -0.14 to 0.00; p = 0.045). Most studies that stratified their sample reported that younger AD onset (usually < 65 years) was associated with more rapid cognitive decline. Other evidence was inconclusive. CONCLUSION: Younger people with AD appear to have a poorer prognosis in terms of faster cognitive decline than older people with AD. More research is required to determine the impact of symptom onset age in VaD and FTD, and on functional decline in all dementias.


Assuntos
Idade de Início , Doença de Alzheimer/fisiopatologia , Demência Vascular/fisiopatologia , Progressão da Doença , Demência Frontotemporal/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Humanos , Estudos Longitudinais
4.
J Alzheimers Dis ; 85(3): 943-955, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34897090

RESUMO

Hypertension is a major risk factor for the pathogenesis of vascular dementia and Alzheimer's disease. Chronic activation of the renin-angiotensin system (RAS) contributes substantially to neuroinflammation. We propose that neuroinflammation arising from chronic RAS activation can initiate and potentiate the onset of hypertension and related dementia. Neuroinflammation induced by chronic activation of the RAS plays a key role in the pathogenesis of dementia. Increased levels of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and transforming growth factor (TGF)-ß have been reported in brain tissue of vascular dementia patients and animal models of vascular dementia induced by either angiotensin II infusion or transverse aortic coarctation. It is proposed that neuronal cell death and synaptic dysfunction induced by neuroinflammation lead to cognitive impairment in dementia. The neuroprotective RAS pathway, regulated by angiotensin-converting enzyme 2 (ACE2) which converts angiotensin II into angiotensin-(1-7), can attenuate hypertension and dementia. Furthermore, the use of anti-hypertensive medications in preventing dementia or cognitive decline in hypertensive patients and animal models of dementia have mostly been beneficial. Current evidence suggests a strong link between RAS induced neuroinflammation and the onset of hypertension and dementia, which warrants further investigation. Strategies to counteract an overactive RAS and enhance the neuroprotective arm of the RAS may help prevent or improve cognitive impairment associated with hypertension.


Assuntos
Citocinas/metabolismo , Demência Vascular/fisiopatologia , Hipertensão/complicações , Inflamação/complicações , Sistema Renina-Angiotensina/fisiologia , Angiotensina I , Angiotensina II/metabolismo , Animais , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/uso terapêutico , Encéfalo/metabolismo , Citocinas/imunologia , Humanos , Hipertensão/tratamento farmacológico , Fragmentos de Peptídeos
5.
Neurosci Lett ; 765: 136266, 2021 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-34571087

RESUMO

DL-3-n-butylphthalide (NBP) has neuroprotective effect on chronic cerebral hypoperfusion animals. Here, we explored the role and underlying mechanism of NBP on autophagy and angiogenesis in rats with vascular dementia (VD). Adult male Sprague-Dawley (SD) rats were subjected to permanent bilateral occlusion of the common carotid arteries (2VO) to establish VD model. These rats were randomly divided into five groups: sham, model, NBP120 (120 mg/kg), Shh siRNA (50 nM), and NBP120 + Shh siRNA groups. Our results showed that NBP treatment attenuated memory damage in rats with VD, as demonstrated by Morris water maze tests. Immunofluorescence (IF) assay revealed that NBP induced neuronal process length and neuronal activity in hippocampus, which were reversed by Shh silencing. Furthermore, NBP treatment also reduced the expression of autophagy marker proteins B-cell lymphoma-2 interacting protein 1 (Beclin 1) and microtubule-associated protein 1 light chain 3 (LC3), which were further enhanced by Shh silencing. Meanwhile, NBP promoted the angiogenesis, which was accompanied by upregulated vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF)-1, and Angiopoietin (Ang) expression in the hippocampus. And Shh siRNA co-treatment blocked the angiogenesis induced by NBP. Altogether, our results established that NBP treatment suppressed autophagy and improved angiogenesis and neurobehavioral recovery in VD rats partly by activating the Shh/Ptch1 signaling pathway.


Assuntos
Autofagia/efeitos dos fármacos , Benzofuranos/farmacologia , Demência Vascular , Neovascularização Fisiológica/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Demência Vascular/metabolismo , Demência Vascular/patologia , Demência Vascular/fisiopatologia , Proteínas Hedgehog/efeitos dos fármacos , Proteínas Hedgehog/metabolismo , Masculino , Receptor Patched-1/efeitos dos fármacos , Receptor Patched-1/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
6.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445515

RESUMO

The impacts of sex differences on the biology of various organ systems and the influences of sex hormones on modulating health and disease have become increasingly relevant in clinical and biomedical research. A growing body of evidence has recently suggested fundamental sex differences in cardiovascular and cognitive function, including anatomy, pathophysiology, incidence and age of disease onset, symptoms affecting disease diagnosis, disease severity, progression, and treatment responses and outcomes. Atrial fibrillation (AF) is currently recognized as the most prevalent sustained arrhythmia and might contribute to the pathogenesis and progression of vascular cognitive impairment (VCI), including a range of cognitive deficits, from mild cognitive impairment to dementia. In this review, we describe sex-based differences and sex hormone functions in the physiology of the brain and vasculature and the pathophysiology of disorders therein, with special emphasis on AF and VCI. Deciphering how sex hormones and their receptor signaling (estrogen and androgen receptors) potentially impact on sex differences could help to reveal disease links between AF and VCI and identify therapeutic targets that may lead to potentially novel therapeutic interventions early in the disease course of AF and VCI.


Assuntos
Fibrilação Atrial/fisiopatologia , Sistema Cardiovascular/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Demência Vascular/fisiopatologia , Hormônios Esteroides Gonadais/metabolismo , Feminino , Humanos , Masculino , Fatores Sexuais
7.
Clin Sci (Lond) ; 135(15): 1929-1944, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34374423

RESUMO

The accumulation of extracellular amyloid-ß (Aß) and intracellular hyperphosphorylated τ proteins in the brain are the hallmarks of Alzheimer's disease (AD). Much of the research into the pathogenesis of AD has focused on the amyloid or τ hypothesis. These hypotheses propose that Aß or τ aggregation is the inciting event in AD that leads to downstream neurodegeneration, inflammation, brain atrophy and cognitive impairment. Multiple drugs have been developed and are effective in preventing the accumulation and/or clearing of Aß or τ proteins. However, clinical trials examining these therapeutic agents have failed to show efficacy in preventing or slowing the progression of the disease. Thus, there is a need for fresh perspectives and the evaluation of alternative therapeutic targets in this field. Epidemiology studies have revealed significant overlap between cardiovascular and cerebrovascular risk factors such as hypertension, diabetes, atherosclerosis and stroke to the development of cognitive impairment. This strong correlation has given birth to a renewed focus on vascular contributions to AD and related dementias. However, few genes and mechanisms have been identified. 20-Hydroxyeicosatetraenoic acid (20-HETE) is a potent vasoconstrictor that plays a complex role in hypertension, autoregulation of cerebral blood flow and blood-brain barrier (BBB) integrity. Multiple human genome-wide association studies have linked mutations in the cytochrome P450 (CYP) 4A (CYP4A) genes that produce 20-HETE to hypertension and stroke. Most recently, genetic variants in the enzymes that produce 20-HETE have also been linked to AD in human population studies. This review examines the emerging role of 20-HETE in AD and related dementias.


Assuntos
Artérias Cerebrais/metabolismo , Circulação Cerebrovascular , Cognição , Disfunção Cognitiva/metabolismo , Demência Vascular/metabolismo , Ácidos Hidroxieicosatetraenoicos/metabolismo , Animais , Artérias Cerebrais/fisiopatologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Demência Vascular/epidemiologia , Demência Vascular/fisiopatologia , Demência Vascular/psicologia , Hemodinâmica , Humanos , Prognóstico , Medição de Risco , Fatores de Risco , Transdução de Sinais
8.
J Clin Invest ; 131(18)2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34351870

RESUMO

Dementia resulting from small vessel diseases (SVDs) of the brain is an emerging epidemic for which there is no treatment. Hypertension is the major risk factor for SVDs, but how hypertension damages the brain microcirculation is unclear. Here, we show that chronic hypertension in a mouse model progressively disrupts on-demand delivery of blood to metabolically active areas of the brain (functional hyperemia) through diminished activity of the capillary endothelial cell inward-rectifier potassium channel, Kir2.1. Despite similar efficacy in reducing blood pressure, amlodipine, a voltage-dependent calcium-channel blocker, prevented hypertension-related damage to functional hyperemia whereas losartan, an angiotensin II type 1 receptor blocker, did not. We attribute this drug class effect to losartan-induced aldosterone breakthrough, a phenomenon triggered by pharmacological interruption of the renin-angiotensin pathway leading to elevated plasma aldosterone levels. This hypothesis is supported by the finding that combining losartan with the aldosterone receptor antagonist eplerenone prevented the hypertension-related decline in functional hyperemia. Collectively, these data suggest Kir2.1 as a possible therapeutic target in vascular dementia and indicate that concurrent mineralocorticoid aldosterone receptor blockade may aid in protecting against late-life cognitive decline in hypertensive patients treated with angiotensin II type 1 receptor blockers.


Assuntos
Anti-Hipertensivos/uso terapêutico , Doenças de Pequenos Vasos Cerebrais/tratamento farmacológico , Doenças de Pequenos Vasos Cerebrais/etiologia , Hiperemia/tratamento farmacológico , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Anlodipino/uso terapêutico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Animais , Anti-Hipertensivos/administração & dosagem , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Circulação Cerebrovascular/efeitos dos fármacos , Circulação Cerebrovascular/fisiologia , Demência Vascular/tratamento farmacológico , Demência Vascular/etiologia , Demência Vascular/fisiopatologia , Modelos Animais de Doenças , Quimioterapia Combinada , Eplerenona/administração & dosagem , Eplerenona/uso terapêutico , Fatores de Risco de Doenças Cardíacas , Humanos , Hiperemia/fisiopatologia , Losartan/administração & dosagem , Losartan/uso terapêutico , Masculino , Camundongos , Microvasos/efeitos dos fármacos , Microvasos/fisiopatologia , Canais de Potássio Corretores do Fluxo de Internalização/efeitos dos fármacos , Canais de Potássio Corretores do Fluxo de Internalização/fisiologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/fisiologia
10.
PLoS One ; 16(7): e0253856, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34237081

RESUMO

INTRODUCTION: Vascular dementia is the second most common cause of dementia. Physical disability and cognitive impairment due to stroke are conditions that considerably affect quality of life. We estimated the prevalence and incidence of possible vascular dementia (PVD) in older adults using data from the Mexican Health and Aging Study (MHAS 2012 and 2015 waves). METHODS: The MHAS is a representative longitudinal cohort study of Mexican adults aged ≥50 years. Data from 14, 893 participants from the 2012 cohort and 14,154 from the 2015 cohort were analyzed to estimate the prevalence and incidence of PVD. Self-respondents with history of stroke were classified as PVD if scores in two or more cognitive domains in the Cross-Cultural Cognitive Examination were ≥ 1.5 standard deviations below the mean on reference norms and if limitations in ≥ 1 instrumental activities of daily living were present. For proxy respondents with history of stroke, we used a score ≥3.4 on the Informant Questionnaire on Cognitive Decline in the Elderly. Crude and standardized rates of prevalent and incident PVD were estimated. RESULTS: Prevalence of PVD was 0.6% (95% CI, 0.5-0.8) (0.5 with age and sex- standardization). Rates increased with age reaching 2.0% among those aged 80 and older and decreased with educational attainment. After 3.0 years of follow-up, 87 new cases of PVD represented an overall incident rate of 2.2 (95% CI, 1.7-2.6) per 1,000 person-years (2.0 with age and sex- standardization). Incidence also increased with advancing age reaching an overall rate of 9.4 (95% CI, 6.3-13.6) per 1,000 person-years for participants aged >80 years. Hypertension and depressive symptoms were strong predictors of incident PVD. CONCLUSION: These data provide new estimates of PVD prevalence and incidence in the Mexican population. We found that PVD incidence increased with age. Males aged 80 years or older showed a greater incidence rate when compared to females, which is comparable to previous estimates from other studies.


Assuntos
Envelhecimento/fisiologia , Demência Vascular/epidemiologia , Qualidade de Vida , Acidente Vascular Cerebral/epidemiologia , Atividades Cotidianas , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Demência Vascular/diagnóstico , Demência Vascular/etiologia , Demência Vascular/fisiopatologia , Feminino , Inquéritos Epidemiológicos/estatística & dados numéricos , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Sexuais , Acidente Vascular Cerebral/complicações
11.
Pharmacol Res ; 170: 105756, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237440

RESUMO

Chronic Cerebral Hypoperfusion(CCH)-induced vascular dementia(VD) is a common neurodegenerative disease which seriously affects the patient's quality of life. Therefore, it is critical to find an effective treatment of VD. Autophagy is a natural regulated mechanism that can remove dysfunctional proteins and organelles, however, over-activation or under-activation can of autophagy can induce the apoptosis of cells. Although autophagy plays a role in the central nervous system is unquestionable, the effects of autophagy in the ischemic brain are still controversial. Some autophagy regulators have been tested, suggesting that both activation and inhibition of autophagy can improve the cognitive function. This article reviews the role of autophagy in CCH-induced VD to discuss whether autophagy has the potential to become a target for drug development and provides several potential compounds for treating vascular dementia.


Assuntos
Autofagia/efeitos dos fármacos , Produtos Biológicos/uso terapêutico , Encéfalo/efeitos dos fármacos , Demência Vascular/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Produtos Biológicos/efeitos adversos , Encéfalo/metabolismo , Encéfalo/patologia , Circulação Cerebrovascular , Demência Vascular/metabolismo , Demência Vascular/patologia , Demência Vascular/fisiopatologia , Humanos , Transdução de Sinais
12.
J Alzheimers Dis ; 82(2): 781-790, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34092632

RESUMO

BACKGROUND: Sulfatides (STs) in cerebrospinal fluid (CSF), as well as magnetic resonance imaging (MRI)-detected white matter hyperintensities (WMHs), may reflect demyelination. Here, we investigated the diagnostic utility of CSF ST levels in the subcortical small vessel type of dementia (SSVD), which is characterized by the presence of brain WMHs. OBJECTIVE: To study the diagnostic utility of CSF ST levels in SSVD. METHODS: This was a mono-center, cross-sectional study of SSVD (n = 16), Alzheimer's disease (n = 40), mixed dementia (n = 27), and healthy controls (n = 33). Totally, 20 ST species were measured in CSF by liquid chromatography-mass spectrometry (LC-MS/MS). RESULTS: CSF total ST levels, as well as CSF levels of hydroxylated and nonhydroxylated ST species, did not differ across the study groups. In contrast, CSF neurofilament light chain (NFL) levels separated the patient groups from the controls. CSF total ST level correlated with CSF/serum albumin ratio in the total study population (r = 0.64, p < 0.001) and in all individual study groups. Furthermore, CSF total ST level correlated positively with MRI-estimated WMH volume in the total study population (r = 0.30, p < 0.05), but it did not correlate with CSF NFL level. CONCLUSION: Although there was some relation between CSF total ST level and WMH volume, CSF ST levels were unaltered in all dementia groups compared to the controls. This suggests that CSF total ST level is a poor biomarker of demyelination in SSVD. Further studies are needed to investigate the mechanisms underlying the marked correlation between CSF total ST level and CSF/serum albumin ratio.


Assuntos
Doença de Alzheimer , Demência Vascular , Doenças Desmielinizantes , Imageamento por Ressonância Magnética/métodos , Sulfoglicoesfingolipídeos/líquido cefalorraquidiano , Substância Branca/diagnóstico por imagem , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico , Cromatografia Líquida/métodos , Estudos Transversais , Demência Vascular/líquido cefalorraquidiano , Demência Vascular/diagnóstico , Demência Vascular/fisiopatologia , Doenças Desmielinizantes/líquido cefalorraquidiano , Doenças Desmielinizantes/diagnóstico , Diagnóstico Diferencial , Técnicas de Diagnóstico Neurológico , Feminino , Humanos , Masculino , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Utilização de Procedimentos e Técnicas , Reprodutibilidade dos Testes , Substância Branca/patologia
13.
J Alzheimers Dis ; 82(2): 871-879, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34092648

RESUMO

BACKGROUND: Most common progressive brain diseases in the elderly are Alzheimer's disease (AD) and vascular dementia (VaD). They present with relatively similar clinical symptoms of cognitive decline, but the underlying pathophysiological mechanisms are different. OBJECTIVE: The aim is to explore the brain connectivity differences between AD and VaD patients compared to mild cognitive impairment (MCI) and normal elderly (Nold) subjects applying graph theory, in particular the Small World (SW) analysis. METHODS: 274 resting state EEGs were analyzed in 100 AD, 80 MCI, 40 VaD, and 54 Nold subjects. Graph theory analyses were applied to undirected and weighted networks obtained by lagged linear coherence evaluated by eLORETA tool. RESULTS: VaD and AD patients presented more ordered low frequency structure (lower value of SW) than Nold and MCI subjects, and more random organization (higher value of SW) in low and high frequency alpha rhythms. Differences between patients have been found in high frequency alpha rhythms in VaD (higher value of SW) with respect to AD, and in theta band with a trend which is more similar to MCI and Nold than to AD. MCI subjects presented a network organization which is intermediate, in low frequency bands, between Nold and patients. CONCLUSION: Graph theory applied to EEG data has proved very useful in identifying differences in brain network patterns in subjects with dementia, proving to be a valid tool for differential diagnosis. Future studies will aim to validate this method to diagnose especially in the early stages of the disease and at single subject level.


Assuntos
Doença de Alzheimer , Encéfalo/fisiopatologia , Disfunção Cognitiva/diagnóstico , Demência Vascular , Eletroencefalografia/métodos , Rede Nervosa/fisiopatologia , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/fisiopatologia , Ondas Encefálicas , Conectoma/métodos , Demência Vascular/diagnóstico , Demência Vascular/fisiopatologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
14.
Neural Plast ; 2021: 8812490, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34104193

RESUMO

Widespread structural and functional alterations have been reported in the two highly prevalent mild cognitive impairment (MCI) subtypes, amnestic MCI (aMCI) and vascular MCI (VaMCI). However, the changing pattern in functional connectivity strength (FCS) remains largely unclear. The aim of the present study is to detect the differences of FCS and to further explore the detailed resting-state functional connectivity (FC) alterations among VaMCI subjects, aMCI subjects, and healthy controls (HC). Twenty-six aMCI subjects, 31 VaMCI participants, and 36 HC participants underwent cognitive assessments and resting-state functional MRI scans. At first, one-way ANCOVA and post hoc analysis indicated significant decreased FCS in the left middle temporal gyrus (MTG) in aMCI and VaMCI groups compared to HC, especially in the VaMCI group. Then, we selected the left MTG as a seed to further explore the detailed resting-state FC alterations among the three groups, and the results indicated that FC between the left MTG and some frontal brain regions were significantly decreased mainly in VaMCI. Finally, partial correlation analysis revealed that the FC values between the left MTG and left inferior frontal gyrus were positively correlated with the cognitive performance episodic memory and negatively related to the living status. The present study demonstrated that different FCS alterations existed in aMCI and VaMCI. These findings may provide a novel insight into the understanding of pathophysiological mechanisms underlying different MCI subtypes.


Assuntos
Amnésia/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Demência Vascular/fisiopatologia , Idoso , Amnésia/psicologia , Mapeamento Encefálico , Disfunção Cognitiva/psicologia , Demência Vascular/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória Episódica , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Testes Neuropsicológicos , Desempenho Psicomotor , Descanso , Lobo Temporal/diagnóstico por imagem
15.
J Stroke Cerebrovasc Dis ; 30(8): 105864, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34062312

RESUMO

OBJECTIVE: Vascular dementia (VaD) is the second most common cause of dementia and a major health concern worldwide. A comprehensive review on VaD is warranted for better understanding and guidance for the practitioner. We provide an updated overview of the epidemiology, pathophysiological mechanisms, neuroimaging patterns as well as current diagnostic and therapeutic approaches. MATERIALS AND METHODS: A narrative review of current literature in VaD was performed based on publications from the database of PubMed, Scopus and Google Scholar up to January, 2021. RESULTS: VaD can be the result of ischemic or hemorrhagic tissue injury in a particular region of the brain which translates into clinically significant cognitive impairment. For example, a cerebral infarct in the speech area of the dominant hemisphere would translate into clinically significant impairment as would involvement of projection pathways such as the arcuate fasciculus. Specific involvement of the angular gyrus of the dominant hemisphere, with resultant Gerstman's syndrome, could have a pronounced effect on functional ability despite being termed a "minor stroke". Small vessel cerebrovascular disease can have a cumulate effect on cognitive function over time. It is unfortunately well recognized that "good" functional recovery in acute ischemic or haemorrhagic stroke, including subarachnoid haemorrhage, does not necessarily translate into good cognitive recovery. The victim may often be left unable to have gainful employment, drive a car safely or handle their affairs independently. CONCLUSIONS: This review should serve as a compendium of updated information on VaD and provide guidance in terms of newer diagnostic and potential therapeutic approaches.


Assuntos
Encéfalo/irrigação sanguínea , Doenças de Pequenos Vasos Cerebrais/complicações , Circulação Cerebrovascular , Cognição , Demência Vascular/etiologia , Acidente Vascular Cerebral Hemorrágico/complicações , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Doenças de Pequenos Vasos Cerebrais/terapia , Demência Vascular/fisiopatologia , Demência Vascular/psicologia , Demência Vascular/terapia , Progressão da Doença , Acidente Vascular Cerebral Hemorrágico/fisiopatologia , Acidente Vascular Cerebral Hemorrágico/terapia , Humanos , Prognóstico , Recuperação de Função Fisiológica , Fatores de Risco
16.
Nat Commun ; 12(1): 3190, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045465

RESUMO

The hippocampus is essential for spatial and episodic memory but is damaged early in Alzheimer's disease and is very sensitive to hypoxia. Understanding how it regulates its oxygen supply is therefore key for designing interventions to preserve its function. However, studies of neurovascular function in the hippocampus in vivo have been limited by its relative inaccessibility. Here we compared hippocampal and visual cortical neurovascular function in awake mice, using two photon imaging of individual neurons and vessels and measures of regional blood flow and haemoglobin oxygenation. We show that blood flow, blood oxygenation and neurovascular coupling were decreased in the hippocampus compared to neocortex, because of differences in both the vascular network and pericyte and endothelial cell function. Modelling oxygen diffusion indicates that these features of the hippocampal vasculature may restrict oxygen availability and could explain its sensitivity to damage during neurological conditions, including Alzheimer's disease, where the brain's energy supply is decreased.


Assuntos
Hipocampo/irrigação sanguínea , Microcirculação/fisiologia , Neocórtex/irrigação sanguínea , Córtex Visual/irrigação sanguínea , Trifosfato de Adenosina/biossíntese , Doença de Alzheimer/fisiopatologia , Animais , Hipóxia Celular/fisiologia , Demência Vascular/fisiopatologia , Feminino , Hipocampo/citologia , Hipocampo/diagnóstico por imagem , Hipocampo/fisiopatologia , Humanos , Microscopia Intravital , Fluxometria por Laser-Doppler , Masculino , Camundongos , Microscopia de Fluorescência por Excitação Multifotônica , Microvasos/diagnóstico por imagem , Microvasos/fisiologia , Modelos Animais , Neocórtex/citologia , Neocórtex/diagnóstico por imagem , Neocórtex/fisiopatologia , Neurônios/metabolismo , Acoplamento Neurovascular/fisiologia , Fosforilação Oxidativa , Oxigênio/análise , Oxigênio/metabolismo , Memória Espacial/fisiologia , Córtex Visual/citologia , Córtex Visual/fisiopatologia
17.
Int J Mol Sci ; 22(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33926146

RESUMO

Vascular dementia (VaD) is the second most common form of dementia worldwide. It is caused by cerebrovascular disease, and patients often show severe impairments of advanced cognitive abilities. Nitric oxide synthase (NOS) and nitric oxide (NO) play vital roles in the pathogenesis of VaD. The functions of NO are determined by its concentration and bioavailability, which are regulated by NOS activity. The activities of different NOS subtypes in the brain are partitioned. Pathologically, endothelial NOS is inactivated, which causes insufficient NO production and aggravates oxidative stress before inducing cerebrovascular endothelial dysfunction, while neuronal NOS is overactive and can produce excessive NO to cause neurotoxicity. Meanwhile, inflammation stimulates the massive expression of inducible NOS, which also produces excessive NO and then induces neuroinflammation. The vicious circle of these kinds of damage having impacts on each other finally leads to VaD. This review summarizes the roles of the NOS/NO pathway in the pathology of VaD and also proposes some potential therapeutic methods that target this pathway in the hope of inspiring novel ideas for VaD therapeutic approaches.


Assuntos
Demência Vascular/fisiopatologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Encéfalo/metabolismo , Transtornos Cerebrovasculares , Demência Vascular/metabolismo , Demência Vascular/terapia , Humanos , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/fisiologia , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/fisiologia , Transdução de Sinais
18.
Neurobiol Aging ; 103: 78-97, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33845399

RESUMO

Vascular contribution to cognitive impairment (VCI) and dementia is related to etiologies that may affect the neurophysiological mechanisms regulating brain arousal and generating electroencephalographic (EEG) activity. A multidisciplinary expert panel reviewed the clinical literature and reached consensus about the EEG measures consistently found as abnormal in VCI patients with dementia. As compared to cognitively unimpaired individuals, those VCI patients showed (1) smaller amplitude of resting state alpha (8-12 Hz) rhythms dominant in posterior regions; (2) widespread increases in amplitude of delta (< 4 Hz) and theta (4-8 Hz) rhythms; and (3) delayed N200/P300 peak latencies in averaged event-related potentials, especially during the detection of auditory rare target stimuli requiring participants' responses in "oddball" paradigms. The expert panel formulated the following recommendations: (1) the above EEG measures are not specific for VCI and should not be used for its diagnosis; (2) they may be considered as "neural synchronization" biomarkers to enlighten the relationships between features of the VCI-related cerebrovascular lesions and abnormalities in neurophysiological brain mechanisms; and (3) they may be tested in future clinical trials as prognostic biomarkers and endpoints of interventions aimed at normalizing background brain excitability and vigilance in wakefulness.


Assuntos
Encéfalo/fisiopatologia , Disfunção Cognitiva/diagnóstico , Demência Vascular/diagnóstico , Eletroencefalografia/métodos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Demência Vascular/etiologia , Demência Vascular/fisiopatologia , Potenciais Evocados/fisiologia , Humanos , Descanso/fisiologia
19.
Oxid Med Cell Longev ; 2021: 8879060, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747352

RESUMO

OBJECTIVE: To explore the oxidative stress mechanism of modified Buyang Huanwu decoction (MBHD) in intervention of vascular dementia (VD) based on systems biology strategy. METHODS: In this study, through the reverse virtual target prediction technology and transcriptomics integration strategy, the active ingredients and potential targets of MBHD treatment of VD were analyzed, and the drug-disease protein-protein interaction (PPI) network was constructed. Then, bioinformatics analysis methods are used for Gene Ontology (GO) enrichment analysis and pathway enrichment analysis, and finally find the core biological process. After that, in animal models, low-throughput technology is used to detect gene expression and protein expression of key molecular targets in oxidative stress-mediated inflammation and apoptosis signaling pathways to verify the mechanism of MBHD treatment of VD rats. Finally, the potential interaction relationship between MBHD and VD-related molecules is further explored through molecular docking technology. RESULTS: There are a total of 54 MBHD components, 252 potential targets, and 360 VD genes. The results of GO enrichment analysis and pathway enrichment analysis showed that MBHD may regulate neuronal apoptosis, nitric oxide synthesis and metabolism, platelet activation, NF-κB signaling pathway-mediated inflammation, oxidative stress, angiogenesis, etc. Among them, SIRT1, NF-κB, BAX, BCL-2, CASP3, and APP may be important targets for MBHD to treat VD. Low-throughput technology (qRT-PCR/WB/immunohistochemical technology) detects oxidative stress-mediated inflammation and apoptosis-related signaling pathway molecules. The molecular docking results showed that 64474-51-7, cycloartenol, ferulic acid, formononetin, kaempferol, liquiritigenin, senkyunone, wallichilide, xanthinin, and other molecules can directly interact with NF-κB p65, BAX, BCL-2, and CASP3. CONCLUSION: The active compounds of MBHD interact with multiple targets and multiple pathways in a synergistic manner, and have important therapeutic effects on VD mainly by balancing oxidative stress/anti-inflammatory and antiapoptotic, enhancing metabolism, and enhancing the immune system.


Assuntos
Demência Vascular/patologia , Medicamentos de Ervas Chinesas/farmacologia , Estresse Oxidativo , Biologia de Sistemas , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Análise por Conglomerados , Demência Vascular/genética , Demência Vascular/fisiopatologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiopatologia , Ligantes , Masculino , Memória/efeitos dos fármacos , Mapas de Interação de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Transdução de Sinais/genética
20.
MEDICC Rev ; 23(1): 55-63, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33780424

RESUMO

INTRODUCTION: Alzheimer disease is related to several risk factors including aging, family history, high blood pressure and diabetes. Studies have shown specific regional cerebral perfusion changes in patients with Alzheimer disease. Some authors state that these changes could appear years before patient memory becomes impaired, enabling early diagnosis in high-risk persons who appear to be healthy. OBJECTIVE: Determine the usefulness of cerebral perfusion studies in Alzheimer patients and first-degree relatives for obtaining additional diagnostic information and detecting functional changes that may suggest elevated disease risk. METHODS: This study involved 128 persons (87 clinically diagnosed with Alzheimer disease and 41 of their first-degree relatives with normal cognition), all from Artemisa Province, Cuba. We performed clinical, laboratory, neuropsychological and genetic (apolipoprotein E-ApoE, e4 allele) tests, as well as cerebral perfusion studies using single photon emission computed tomography after administering 740-925 MBq of 99m Tc-ECD, following internationally standardized protocols. RESULTS: In the Alzheimer disease group, the cerebral single photon emission computed tomography showed a typical Alzheimer pattern (bilateral posterior temporal-parietal hypoperfusion) in 77% (67/87) of participants; 35.9% (28/67) in stage 1; 51.3% (40/67) in stage 2; and 12.8% (10/67) in stage 3 of the disease. In this group, 12.7% (11/87) had mild or unilateral cerebral perfusion changes; 5.7% (5/87) vascular dementia; 3.4% (3/87) frontal dementia; and 1.2% (1/87) normal cerebral perfusion. Of the patients, 28.7% (25/87) received a different classification of stage and disease diagnosis after cerebral perfusion results were considered. In the relative group, 14.6% (6/41) had cerebral perfusion abnormalities. Among these, 7.1% (3/41) were mild bilateral temporal-parietal hypoperfusion; 4.8% (2/41) mild unilateral temporal-parietal hypoperfusion; and 2.4% (1/41) had perfusion defecits in their right frontal lobes. Of patients with typical Alzheimer disease patterns in the cerebral single photon emission computed tomography, 76.6% (52/67) had positive ApoE e4. All relatives with perfusion abnormalities (6/6) had positive ApoE e4. CONCLUSIONS: Cerebral perfusion studies confirmed the Alzheimer disease diagnosis, classified disease stages, and differentiated between the types of dementia. The test showed perfusion changes in several asymptomatic first-degree relatives with positive ApoE e4, which could be predictors of disease. The technique was useful for evaluating patients and their relatives.


Assuntos
Doença de Alzheimer/fisiopatologia , Doenças Assintomáticas , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular , Saúde da Família , Sintomas Prodrômicos , Adulto , Idoso , Doença de Alzheimer/diagnóstico , Cuba , Demência Vascular/diagnóstico , Demência Vascular/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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