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1.
Mol Neurobiol ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565786

RESUMO

(CCG) short tandem repeats (STRs) are predominantly enriched in genic regions, mutation hotspots for C to T truncating substitutions, and involved in various neurological and neurodevelopmental disorders. However, intact blocks of this class of STRs are widely overlooked with respect to their link with natural selection. The human neuron-specific gene, DISP2 (dispatched RND transporter family member 2), contains a (CCG) repeat in its 5' untranslated region. Here, we sequenced this STR in a sample of 448 Iranian individuals, consisting of late-onset neurocognitive disorder (NCD) (N = 203) and controls (N = 245). We found that the region spanning the (CCG) repeat was highly mutated, resulting in several flanking (CCG) residues. However, an 8-repeat of the (CCG) repeat was predominantly abundant (frequency = 0.92) across the two groups. While the overall distribution of genotypes was not different between the two groups (p > 0.05), we detected four genotypes in the NCD group only (2% of the NCD genotypes, Mid-p = 0.02), consisting of extreme short alleles, 5- and 6-repeats, that were not detected in the control group. The patients harboring those genotypes received the diagnoses of probable Alzheimer's disease and vascular dementia. We also found six genotypes in the control group only (2.5% of the control genotypes, Mid-p = 0.01) that consisted of the 8-repeat and extreme long alleles, 9- and 10-repeats, of which the 10-repeat was not detected in the NCD group. The (CCG) repeat specifically expanded in primates. In conclusion, we report an indication of natural selection at a novel hypermutable region in the human genome and divergent alleles and genotypes in late-onset NhCDs and controls. These findings reinforce the hypothesis that a collection of rare alleles and genotypes in a number of genes may unambiguously contribute to the cognition impairment component of late-onset NCDs.

2.
Neurol Res ; : 1-13, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563325

RESUMO

BACKGROUND: Vascular dementia (VD) is the second most common type of dementia worldwide. Previous studies have proven that transcranial direct current stimulation (tDCS) has potential applications in relieving cognitive impairment in VD animal models. The purpose of this study was to probe the mechanism by which tDCS combined with swimming exercise improves the learning and memory abilities of VD model rats. METHOD: The VD rat model was induced using the permanent bilateral common carotid artery occlusion (2-VO) method; tDCS was applied to the rats and then they took part in swimming exercises. Rat memory, platform crossing time, and platform crossing frequency were analyzed via a water maze experiment. Nerve damage in the cortex and hippocampal CA1 area of the rats was observed using Nissl staining. Western blotting, immunohistochemistry, immunofluorescence staining and reverse transcription quantitative polymerase chain reaction (RT - qPCR) were used to determine the expression of related proteins and genes. The levels of oxidative stress were detected by kits. RESULTS: We demonstrated that VD model rats treated with tDCS combined with swimming exercise exhibited significant improvement in memory, and VD model rats exhibited significantly reduced neuronal loss in the hippocampus, and reduced microglial activation and M1 polarization. tDCS combined with swimming exercise protects VD model rats from oxidative stress through the miR-223-3p/protein arginine methyltransferase 8 (PRMT8) axis and inhibits the activation of the TLR4/NF-κB signaling pathway. CONCLUSION: Our results suggest that tDCS combined with swimming exercise improved the learning and memory ability of VD model rats by regulating the expression of PRMT8 through miR-223-3p to affect microglial activation and M1 polarization.

3.
J Alzheimers Dis ; 98(4): 1503-1514, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38640163

RESUMO

Background: Population-based studies have shown an increased risk of dementia after infections, but weaker links were reported for autoimmune diseases. Evidence is scarce for whether the links may be modified by the dementia or exposure subtype. Objective: We aimed to investigate the association between infections and/or autoimmune diseases and rates of major types of dementias in the short- and long terms. Methods: Nationwide nested case-control study of dementia cases (65+ years) diagnosed in Denmark 2016-2020 and dementia-free controls. Exposures were hospital-diagnosed infections and autoimmune diseases in the preceding 35 years. Two groups of dementia cases were those diagnosed in memory clinics (MC) and those diagnosed outside memory clinics (non-memory clinic cases, NMC). Results: In total, 26,738 individuals were MC and 12,534 were NMC cases. Following any infection, the incidence rate ratio (IRR) for MC cases was 1.23 (95% CI 1.20-1.27) and 1.70 for NMC cases (1.62-1.76). Long-term increased rates were seen for vascular dementia and NMC cases. IRRs for autoimmune diseases were overall statistically insignificant. Conclusions: Cases with vascular dementia and not Alzheimer's disease, and a subgroup of cases identified with poorer health have increased long-term risk following infections. Autoimmune diseases were not associated with any type of dementia. Notably increased risks (attributed to the short term) and for NMC cases may indicate that immunosenescence rather than de novo infection explains the links. Future focus on such groups and on the role of vascular pathology will explain the infection-dementia links, especially in the long term.


Assuntos
Doença de Alzheimer , Doenças Autoimunes , Demência Vascular , Humanos , Estudos de Casos e Controles , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/epidemiologia , Doenças Autoimunes/epidemiologia , Hospitais
4.
Arch Gerontol Geriatr ; 124: 105441, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643666

RESUMO

BACKGROUND: The breakdown of the blood-brain barrier (BBB) is intricately linked to the onset and advancement of cognitive impairment and dementia. This investigation explores the correlation between blood-brain barrier permeability, assessed through the cerebrospinal fluid/serum albumin ratio (QAlb), in a clinical cohort and the evolution of cognitive decline. METHODS: This prospective observational cohort study included 295 participants. Cognitive decline progression was characterized by an escalation in the overall deterioration scale and/or clinical dementia rating scores. The investigation delves into the correlation between blood-brain barrier permeability and the advancement of cognitive impairment among patients. RESULTS: The APOE 4 allele and diabetes mellitus among individuals exhibited increased BBB permeability (P < 0.05). Moreover, AD patients exhibited the highest QAlb levels, signifying elevated BBB permeability compared to individuals with MCI and SCD (P < 0.05). After mean 17 months following up, 117 patients (51.31 %) were identified as experiencing cognitive decline progression, and we found that only AD diagnosis, CDR, and QAlb (All P < 0.05) were significant predictors of cognitive decline progression. CONCLUSION: Our study emphasizes the clinical relevance of QAlb in detecting individuals with an elevated risk of cognitive decline. It suggests that heightened BBB permeability could contribute to clinical deterioration and serves as a plausible therapeutic target.

5.
Alzheimers Dement ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629936

RESUMO

INTRODUCTION: Cerebral small vessel disease (SVD) is a common cause of stroke/vascular dementia with few effective treatments. Neuroinflammation and increased blood-brain barrier (BBB) permeability may influence pathogenesis. In rodent models, minocycline reduced inflammation/BBB permeability. We determined whether minocycline had a similar effect in patients with SVD. METHODS: MINERVA was a single-center, phase II, randomized, double-blind, placebo-controlled trial. Forty-four participants with moderate-to-severe SVD took minocycline or placebo for 3 months. Co-primary outcomes were microglial signal (determined using 11C-PK11195 positron emission tomography) and BBB permeability (using dynamic contrast-enhanced MRI). RESULTS: Forty-four participants were recruited between September 2019 and June 2022. Minocycline had no effect on 11C-PK11195 binding (relative risk [RR] 1.01, 95% confidence interval [CI] 0.98-1.04), or BBB permeability (RR 0.97, 95% CI 0.91-1.03). Serum inflammatory markers were not affected. DISCUSSION: 11C-PK11195 binding and increased BBB permeability are present in SVD; minocycline did not reduce either process. Whether these pathophysiological mechanisms are disease-causing remains unclear. INTERNATIONAL CLINICAL TRIALS REGISTRY PORTAL IDENTIFIER: ISRCTN15483452 HIGHLIGHTS: We found focal areas of increased microglial signal and increased blood-brain barrier permeability in patients with small vessel disease. Minocycline treatment was not associated with a change in these processes measured using advanced neuroimaging. Blood-brain barrier permeability was dynamic but MRI-derived measurements correlated well with CSF/serum albumin ratio. Advanced neuroimaging is a feasible outcome measure for mechanistic clinical trials.

6.
Zhongguo Zhong Yao Za Zhi ; 49(4): 902-911, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621897

RESUMO

Alzheimer's disease(AD), vascular dementia(VD), and traumatic brain injury(TBI) are more common cognitive impairment diseases characterized by high disability and mortality rates, imposing a heavy burden on individuals and their families. Although AD, VD, and TBI have different specific mechanisms, their pathogenesis is closely related to the nucleotide-binding oligome-rization domain-like receptor protein 3(NLRP3). The NLRP3 inflammasome is involved in neuroinflammatory responses, mediating microglial polarization, regulating the reduction of amyloid ß-protein(Aß) deposition, neurofibrillary tangles(NFTs) formation, autophagy regulation, and maintaining brain homeostasis, and synaptic stability, thereby contributing to the development of AD, VD, and TBI. Previous studies have shown that traditional Chinese medicine(TCM) can alleviate neuroinflammation, promote microglial polarization towards the M2 phenotype, reduce Aß deposition and NFTs formation, regulate autophagy, and maintain brain homeostasis by intervening in NLRP3 inflammasome, hence exerting a role in preventing and treating cognitive impairment-related diseases, reducing psychological and economic pressure on patients, and improving their quality of life. Therefore, this article elucidated the role of NLRP3 inflammasome in AD, VS, and TBI, and provided a detailed summary of the latest research results on TCM intervention in NLRP3 inflammasome for the prevention and treatment of these diseases, aiming to inherit the essence of TCM and provide references and foundations for clinical prevention and treatment of cognitive impairment-related diseases with TCM. Meanwhile, this also offers insights and directions for further research in TCM for the prevention and treatment of cognitive impairment-related diseases.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Peptídeos beta-Amiloides/metabolismo , Medicina Tradicional Chinesa , Qualidade de Vida , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/prevenção & controle , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/prevenção & controle
7.
Immun Ageing ; 21(1): 23, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570813

RESUMO

BACKGROUND: It is of interest whether inflammatory biomarkers can improve dementia prediction models, such as the widely used Cardiovascular Risk Factors, Aging and Dementia (CAIDE) model. METHODS: The Olink Target 96 Inflammation panel was assessed in a nested case-cohort design within a large, population-based German cohort study (n = 9940; age-range: 50-75 years). All study participants who developed dementia over 20 years of follow-up and had complete CAIDE variable data (n = 562, including 173 Alzheimer's disease (AD) and 199 vascular dementia (VD) cases) as well as n = 1,356 controls were selected for measurements. 69 inflammation-related biomarkers were eligible for use. LASSO logistic regression and bootstrapping were utilized to select relevant biomarkers and determine areas under the curve (AUCs). RESULTS: The CAIDE model 2 (including Apolipoprotein E (APOE) ε4 carrier status) predicted all-cause dementia, AD, and VD better than CAIDE model 1 (without APOE ε4) with AUCs of 0.725, 0.752 and 0.707, respectively. Although 20, 7, and 4 inflammation-related biomarkers were selected by LASSO regression to improve CAIDE model 2, the AUCs did not increase markedly. CAIDE models 1 and 2 generally performed better in mid-life (50-64 years) than in late-life (65-75 years) sub-samples of our cohort, but again, inflammation-related biomarkers did not improve their predictive abilities. CONCLUSIONS: Despite a lack of improvement in dementia risk prediction, the selected inflammation-related biomarkers were significantly associated with dementia outcomes and may serve as a starting point to further elucidate the pathogenesis of dementia.

8.
Can J Cardiol ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38579965

RESUMO

Vascular dementia (VaD) is a prevalent form of cognitive impairment with underlying vascular etiology. In this review, we examine recent genetic advancements in our understanding of VaD, encompassing a range of methodologies including genome-wide association studies (GWAS), polygenic risk scores (PRS), heritability estimates, and family studies for monogenic disorders revealing the complex and heterogeneous nature of the disease. We report well-known genetic associations and highlight potential pathways and mechanisms implicated in VaD and its pathological risk factors, including stroke, cerebral small vessel diseases and cerebral amyloid angiopathy. Moreover, we discuss important modifiable risk factors such as hypertension, diabetes, and dyslipidemia, emphasizing the importance of a multifactorial approach in prevention, treatment, and understanding the genetic basis of VaD. Lastly, we outline several areas of scientific advancements to improve clinical care, highlighting that large-scale collaborative efforts, together with an integromics approach can enhance the robustness of genetic discoveries. Indeed, understanding the genetics of VaD and its pathophysiological risk factors hold the potential to redefine VaD based on molecular mechanisms and generate novel diagnostic, prognostic, and therapeutic tools.

9.
Brain Res ; : 148917, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582415

RESUMO

Exploring the intricate pathogenesis of Vascular Dementia (VD), there is a noted absence of potent treatments available in the current medical landscape. A new brain-protective medication developed in China, Edaravone dexboeol (EDB), has shown promise due to its antioxidant and anti-inflammatory properties, albeit with a need for additional research to elucidate its role and mechanisms in VD contexts. In a research setup, a VD model was established utilizing Sprague-Dawley (SD) rats, subjected to permanent bilateral typical carotid artery occlusion (2VO). Behavioral assessment of the rats was conducted using the Bederson test and pole climbing test, while cognitive abilities, particularly learning and memory, were evaluated via the novel object recognition test and the Morris water maze test. Ensuing, the levels of malondialdehyde (MDA), superoxide dismutase (SOD), IL-1ß, IL-6, IL-4, and tumor necrosis factor-α (TNF-α) were determined through Enzyme-Linked Immunosorbent Assay (ELISA). Synaptic plasticity-related proteins, synaptophysin (SYP), post-synaptic density protein 95 (PSD-95), and N-methyl-D-aspartate (NMDA) receptor proteins (NR1, NR2A, NR2B) were investigated via Western blotting technique. The findings imply that EDB has the potential to ameliorate cognitive deficiencies, attributed to VD, by mitigating oxidative stress, dampening inflammatory responses, and modulating the NMDA receptor signaling pathway, furnishing new perspectives into EDB's mechanism and proposing potential avenues for therapeutic strategies in managing VD.

10.
Front Cell Dev Biol ; 12: 1343962, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628595

RESUMO

Tauopathies are neurodegenerative diseases characterized by deposits of abnormal Tau protein in the brain. Conventional tauopathies are often defined by a limited number of Tau epitopes, notably neurofibrillary tangles, but emerging evidence suggests structural heterogeneity among tauopathies. The prolyl isomerase Pin1 isomerizes cis P-tau to inhibit the development of oligomers, tangles and neurodegeneration in multiple neurodegenerative diseases such as Alzheimer's disease, traumatic brain injury, vascular contribution to cognitive impairment and dementia (VCID) and preeclampsia (PE). Thus, cis P-tau has emerged as an early etiological driver, blood marker and therapeutic target for multiple neurodegenerative diseases, with clinical trials ongoing. The discovery of cis P-tau and other tau pathologies in VCID and PE calls attention for simplistic classification of tauopathy in neurodegenerative diseases. These recent advances have revealed the exciting novel role of the Pin1-cis P-tau axis in the development and treatment of vascular contribution to cognitive impairment and dementia and preeclampsia.

11.
Geroscience ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639833

RESUMO

Cerebral microhemorrhages (CMHs, also known as cerebral microbleeds) are a critical but frequently underestimated aspect of cerebral small vessel disease (CSVD), bearing substantial clinical consequences. Detectable through sensitive neuroimaging techniques, CMHs reveal an extensive pathological landscape. They are prevalent in the aging population, with multiple CMHs often being observed in a given individual. CMHs are closely associated with accelerated cognitive decline and are increasingly recognized as key contributors to the pathogenesis of vascular cognitive impairment and dementia (VCID) and Alzheimer's disease (AD). This review paper delves into the hypothesis that atherosclerosis, a prevalent age-related large vessel disease, extends its pathological influence into the cerebral microcirculation, thereby contributing to the development and progression of CSVD, with a specific focus on CMHs. We explore the concept of vascular aging as a continuum, bridging macrovascular pathologies like atherosclerosis with microvascular abnormalities characteristic of CSVD. We posit that the same risk factors precipitating accelerated aging in large vessels (i.e., atherogenesis), primarily through oxidative stress and inflammatory pathways, similarly instigate accelerated microvascular aging. Accelerated microvascular aging leads to increased microvascular fragility, which in turn predisposes to the formation of CMHs. The presence of hypertension and amyloid pathology further intensifies this process. We comprehensively overview the current body of evidence supporting this interconnected vascular hypothesis. Our review includes an examination of epidemiological data, which provides insights into the prevalence and impact of CMHs in the context of atherosclerosis and CSVD. Furthermore, we explore the shared mechanisms between large vessel aging, atherogenesis, microvascular aging, and CSVD, particularly focusing on how these intertwined processes contribute to the genesis of CMHs. By highlighting the role of vascular aging in the pathophysiology of CMHs, this review seeks to enhance the understanding of CSVD and its links to systemic vascular disorders. Our aim is to provide insights that could inform future therapeutic approaches and research directions in the realm of neurovascular health.

13.
Heart Rhythm ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38604586

RESUMO

BACKGROUND: Atrial fibrillation (AF) is associated with the development of dementia and observational studies have shown that oral anticoagulation (OAC) and catheter ablation reduce dementia risk. However, such studies did not consistently report on periprocedural anticoagulation and long term OAC coverage, for which reason the separate effect of AF ablation on dementia risk could not be established. OBJECTIVE: We evaluated the protective effect of AF ablation in large cohort who received optimized anticoagulation and compared them with patients who were managed medically. METHODS: We retrospectively included 5,912 consecutive patients who underwent first-time catheter ablation for AF between 2008 and 2018 and compared them with 52,681 control individuals from the Swedish Patient Register. Propensity score matching produced two cohorts of equal size (n=3,940) with similar baseline characteristics. Dementia diagnosis was identified based on ICD-codes from the patient register. RESULTS: The majority of PS-matched patients were on an OAC at the start (94.5%) and end (75.0%) of the study. Mean follow-up was 4.9±2.8 years. Catheter ablation was associated with lower risk for the dementia diagnosis compared with the control group (HR 0.44, 95% CI 0.22-0.86, P=0.017). The result was similar when including patients with a stroke diagnosis prior to inclusion (HR 0.50, 95% CI 0.28-0.89, P=0.019) and after adjusting for the competing risk of death (HR 0.41, 95% CI 0.20-0.86, P=0.018). CONCLUSIONS: Catheter ablation of AF in patients with optimized OAC therapy was associated with a reduction in dementia diagnosis, even after adjusting for potential confounders and for competing risk of death.

14.
Front Pharmacol ; 15: 1374408, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659577

RESUMO

Cerebrovascular diseases and their sequalae, such as ischemic stroke, chronic cerebral hypoperfusion, and vascular dementia are significant contributors to adult disability and cognitive impairment in the modern world. Astrocytes are an integral part of the neurovascular unit in the CNS and play a pivotal role in CNS homeostasis, including ionic and pH balance, neurotransmission, cerebral blood flow, and metabolism. Astrocytes respond to cerebral insults, inflammation, and diseases through unique molecular, morphological, and functional changes, collectively known as reactive astrogliosis. The function of reactive astrocytes has been a subject of debate. Initially, astrocytes were thought to primarily play a supportive role in maintaining the structure and function of the nervous system. However, recent studies suggest that reactive astrocytes may have both beneficial and detrimental effects. For example, in chronic cerebral hypoperfusion, reactive astrocytes can cause oligodendrocyte death and demyelination. In this review, we will summarize the (1) roles of ion transporter cascade in reactive astrogliosis, (2) role of reactive astrocytes in vascular dementia and related dementias, and (3) potential therapeutic approaches for dementing disorders targeting reactive astrocytes. Understanding the relationship between ion transporter cascade, reactive astrogliosis, and cerebrovascular diseases may reveal mechanisms and targets for the development of therapies for brain diseases associated with reactive astrogliosis.

15.
Int J Stroke ; : 17474930241252556, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651759

RESUMO

BACKGROUND: There are major challenges in determining the aetiology of vascular cognitive impairment (VCI) clinically, especially in the presence of mixed pathologies, such as vascular and amyloid. Most recently, two criteria (American Heart Association/American Stroke Association [AHA/ASA] and Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition [DSM-V]) have been proposed for the clinical diagnosis of VCI but have not as yet been validated using neuroimaging. AIMS: This study aims to determine whether the AHA/ASA and DSM-V criteria for VCI can distinguish between cases with predominantly vascular pathology and cases with mixed pathology. METHODS: 186 subjects were recruited from a cross-sectional memory clinic-based study at the National University Hospital, Singapore. All subjects underwent clinical and neuropsychological assessment, MRI and [11C] PiB PET scans. Diagnosis of the etiological subtypes of VCI [probable vascular mild cognitive impairment (VaMCI), possible VaMCI, non-VaMCI, probable vascular dementia (VaD), possible VaD, non-VaD] were performed following AHA/ASA and DSM-V criteria. Brain amyloid burden was determined for each subject with standardised uptake value ratio (SUVR) values ≥ 1.5 classified as amyloid positive. RESULTS: Using κ statistics, both criteria had excellent agreement for probable VaMCI, probable VaD, and possible VaD (κ=1.00), and good for possible VaMCI (κ=0.71). Using the AHA/ASA criteria, the amyloid positivity of probable VaMCI (3.8%) and probable VaD (15%) was significantly lower compared to possible VaMCI (26.7%), non-VaMCI (33.3%), possible VaD (73.3%) and non-VaD (76.2%) )(p<0.001). Similarly, using the DSM-V criteria the amyloid positivity of probable VaMCI (3.8%) and probable VaD (15%) were significantly lower compared to possible VaMCI (26.3%), non-VaMCI (32.1%), possible VaD (73.3%) and non-VaD (76.2%)(p<0.001). In both criteria, there was good agreement in differentiating individuals with non-VaD and possible VaD, with significantly higher (p<0.001) global [11C]-PiB SUVR, from individuals with probable VaMCI and probable VaD, who had predominant vascular pathology. CONCLUSIONS: The AHA/ASA and DSM-V criteria for VCI can identify VCI cases with little to no concomitant amyloid pathology, hence supporting the utility of AHA/ASA and DSM-V criteria in diagnosing patients with predominant vascular pathology.

16.
Neuropeptides ; 105: 102428, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38583362

RESUMO

RNA methylation can epigenetically regulate learning and memory. However, it is unclear whether RNA methylation plays a critical role in the pathophysiology of Vascular dementia (VD). Here, we report that expression of the fat mass and obesity associated gene (FTO), an RNA demethylase, is downregulated in the hippocampus in models of VD. Through prediction and dual-luciferase reporters validation studies, we observed that miRNA-711 was upregulated after VD and could bind to the 3'-untranslated region of FTO mRNA and regulate its expression in vitro. Methylated RNA immunoprecipitation (MeRIP)-qPCR assay and functional study confirmed that Syn1 was an important target gene of FTO. This suggests that FTO is an important regulator of Syn1. FTO upregulation by inhibition of miR-711 in the hippocampus relieves synaptic association protein and synapse deterioration in vivo, whereas FTO downregulation by miR-711 agomir in the hippocampus leads to aggravate the synapse deterioration. FTO upregulation by inhibition of miR-711 relieves cognitive impairment of rats VD model, whereas FTO downregulation by miR-711 deteriorate cognitive impairment. Our findings suggest that FTO is a regulator of a mechanism underlying RNA methylation associated with spatial cognitive dysfunction after chronic cerebral hypoperfusion.

17.
Ann Indian Acad Neurol ; 27(1): 34-39, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495239

RESUMO

Background: Deep cerebral venous thrombosis (DCVT) can have long-term functional and cognitive sequelae. Although literature exists on cognitive impairment after arterial stroke, cognitive sequelae after cerebral venous thrombosis (CVT) are much less studied. Methods: Clinical records of 29 patients diagnosed with DCVT were reviewed. The Modified Telephonic Interview for Cognitive Status (TICS-M) was adapted and validated in the regional language (Kannada) and applied to 18 patients with DCVT, at a mean follow-up duration of 5.32 years. Screening for depression was done via telephonic Patient Health Questionnaire-9 (PHQ-9)-Kannada version, and functional status was screened by applying the modified Rankin Scale (mRS). Results: DCVT had a mortality rate of 10.34% due to acute complications. mRS scores of 0-1 were achieved at follow-up in all patients who survived. Receiver operating characteristic (ROC) analysis revealed a cutoff of ≤44.5 (maximum score of 49) for the diagnosis of cognitive impairment via TICS-M (Kannada version) in DCVT patients. Evidence of cognitive dysfunction was seen in eight patients (42.10%), and three patients (16.66%) had evidence of depression. Conclusions: Survivors of acute DCVT can potentially have long-term cognitive sequelae. Screening for cognitive dysfunction, depression, and functional status can be effectively done using telephonically applied scales that are adapted to the local language. Neuropsychological evaluation and early cognitive rehabilitation can be initiated for patients in whom deficits are identified on cognitive screening.

18.
Sci Rep ; 14(1): 7116, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531892

RESUMO

This study aimed to investigate structural synaptic plasticity in the medial prefrontal cortex of rats under treadmill exercise pretreatment or naive conditions in a vascular dementia model, followed by recognition memory performance in a novel object recognition task. In this study, 24 Sprague-Dawley rats were obtained and randomly assigned into 4 groups as follows: control group (Con group, n = 6), vascular dementia (VD group, n = 6), exercise and vascular dementia group (Exe + VD group, n = 6), and exercise group (Exe group, n = 6). Initially, 4 weeks of treadmill exercise intervention was administered to the rats in the Exe + VD and Exe groups. Then, to establish the vascular dementia model, the rats both in the VD and Exe + VD groups were subjected to bilateral common carotids arteries surgery. One week later, open-field task and novel recognition memory task were adopted to evaluate anxiety-like behavior and recognition memory in each group. Then, immunofluorescence and Golgi staining were used to evaluate neuronal number and spine density in the rat medial prefrontal cortex. Transmission electron microscopy was used to observe the synaptic ultrastructure. Finally, microdialysis coupled with high-performance liquid chromatography was used to assess the levels of 5-HT and dopamine in the medial prefrontal cortex. The behavior results showed that 4 weeks of treadmill exercise pretreatment significantly alleviated recognition memory impairment and anxiety-like behavior in VD rats (P < 0.01), while the rats in VD group exhibited impaired recognition memory and anxiety-like behavior when compared with the Con group (P < 0.001). Additionally, NeuN immunostaining results revealed a significant decrease of NeuN-marked neuron in the VD group compared to Con group (P < 0.01), but a significantly increase in this molecular marker was found in the Exe + VD group compared to the Con group (P < 0.01). Golgi staining results showed that the medial prefrontal cortex neurons in the VD group displayed fewer dendritic spines than those in the Con group (P < 0.01), and there were more spines on the dendrites of medial prefrontal cortex cells in Exe + VD rats than in VD rats (P < 0.01). Transmission electron microscopy further revealed that there was a significant reduction of synapses intensity in the medial prefrontal cortex of rats in the VD group when compared with the Con group(P < 0.01), but physical exercise was found to significantly increased synapses intensity in the VD model (P < 0.01). Lastly, the levels of dopamine and 5-HT in the medial prefrontal cortex of rats in the VD group was significantly lower compared to the Con group (P < 0.01), and treadmill exercise was shown to significantly increased the levels of dopamine and 5-HT in the VD rats (P < 0.05). Treadmill exercise pretreatment ameliorated structural synaptic plasticity impairments of medial prefrontal cortex in VD rat and improved recognition memory.


Assuntos
Demência Vascular , Dopamina , Ratos , Animais , Ratos Sprague-Dawley , Serotonina , Plasticidade Neuronal/fisiologia , Transtornos da Memória , Córtex Pré-Frontal , Hipocampo
19.
J Integr Neurosci ; 23(3): 66, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38538218

RESUMO

Neuropeptides are endogenous active substances within the central and peripheral nervous systems that play important roles in a wide range of brain functions, including metabolism, food intake, social behavior, reproduction, learning, sleep, and wakefulness. This article reviews recent advances in the involvement of neuropeptides in vascular dementia. Neuropeptides are present in the brain as chemical signals and last for nearly 50 years. Peptide hormones are chemical signals of the endocrine system. Thus, neuropeptides are the most diverse class of signaling molecules in the brain, involving the genomes of many mammals, encoding neuropeptide precursors and many bioactive neuropeptides. Here the aim is to describe the recent advances in classical neuropeptides, as well as putative neuropeptides from other families, in the control of or as diagnostic tools for vascular dementia. Additionally, its molecular mechanisms are described to explore new avenues of treatment and early diagnosis, as there is increasing evidence that dysregulation of vascular processes is associated with different pathological conditions.


Assuntos
Demência Vascular , Neuropeptídeos , Animais , Humanos , Demência Vascular/diagnóstico , Neuropeptídeos/metabolismo , Encéfalo/metabolismo , Transdução de Sinais , Biomarcadores/metabolismo , Mamíferos/metabolismo
20.
Aging (Albany NY) ; 16(5): 4363-4377, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38441564

RESUMO

BACKGROUND: Neuronal injury in chronic cerebral hypoperfusion (CCH) is the main pathogenic factor of vascular dementia (VD). Clinically, there isn't a drug specifically for VD; instead, the majority of medications used to treat Alzheimer's disease (AD) are also used to treat VD. Based on the proven anti-inflammatory and antioxidant effects of Probucol, we hypothesized that it may have therapeutic effects on VD, but more research is required to determine its exact mechanism of action. METHODS: In vivo experiment: We used SD rats and most commonly used bilateral carotid artery occlusion (2-VO) in VD for modeling. After successful modeling, SD rats were given Probucol 3.5 mg/kg/day for 8 weeks to evaluate the therapeutic effect. In vitro experiment: BV-2 microglia of rats were cultured and divided into Control group and Probucol group. Each group was treated with hypoxia-hypoglycemia, hypoxia-hypoglycemia hydrogen peroxide and hypoxia-hypoglycemia hydrogen peroxide Syk inhibitor respectively. RESULTS: The results of immunofluorescence and Western blot showed that Probucol could significantly improve the cognitive impairment induced by CCH, and the neuronal damage was also attenuated. On the one hand, the underlying mechanism of Probucol was to reduce oxidative stress and cell apoptosis of hippocampal neurons by inhibiting the expression of phosphorylated spleen tyrosine kinase (P-Syk); On the other hand, it exerted a protective effect by reducing NLRP3-dependent cell pyroptosis and inhibiting neuroinflammation induced by microglia activation. CONCLUSION: Probucol could reduce oxidative stress and cell apoptosis by inhibiting the Syk/ROS signaling pathway, thereby improving CCH-induced cognitive impairment in vitro and in vivo.


Assuntos
Isquemia Encefálica , Demência Vascular , Hipoglicemia , Ratos , Animais , Demência Vascular/tratamento farmacológico , Demência Vascular/etiologia , Demência Vascular/metabolismo , Probucol/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ratos Sprague-Dawley , Piroptose , Peróxido de Hidrogênio/farmacologia , Isquemia Encefálica/metabolismo , Hipocampo/metabolismo , Hipóxia/metabolismo
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