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1.
Stroke ; 53(3): 698-709, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34781708

RESUMO

BACKGROUND AND PURPOSE: Cerebral small vessel disease is characterized by progressive cerebral white matter changes (WMCs). This study aimed to compare the effects of cilostazol and aspirin on changes in WMC volume in patients with cerebral small vessel disease. METHODS: In a multicenter, double-blind, randomized controlled trial, participants with moderate or severe WMCs and at least one lacunar infarction detected on brain magnetic resonance imaging were randomly assigned to the cilostazol and aspirin groups in a 1:1 ratio. Cilostazol slow release (200 mg) or aspirin (100 mg) capsules were administered once daily for 2 years. The primary outcome was the change in WMC volume on magnetic resonance images from baseline to 2 years. Secondary imaging outcomes include changes in the number of lacunes or cerebral microbleeds, fractional anisotropy, and mean diffusivity on diffusion tensor images, and brain atrophy. Secondary clinical outcomes include all ischemic strokes, all ischemic vascular events, and changes in cognition, motor function, mood, urinary symptoms, and disability. RESULTS: Between July 2013 and August 2016, 256 participants were randomly assigned to the cilostazol (n=127) and aspirin (n=129) groups. Over 2 years, the percentage of WMC volume to total WM volume and the percentage of WMC volume to intracranial volume increased in both groups, but neither analysis showed significant differences between the groups. The peak height of the mean diffusivity histogram in normal-appearing WMs was significantly reduced in the aspirin group compared with the cilostazol group. Cilostazol significantly reduced the risk of ischemic vascular event compared with aspirin (0.5 versus 4.5 cases per 100 person-years; hazard ratio, 0.11 [95% CI, 0.02-0.89]). CONCLUSIONS: There was no significant difference between the effects of cilostazol and aspirin on WMC progression in patients with cerebral small vessel disease. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01932203.


Assuntos
Aspirina/administração & dosagem , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/tratamento farmacológico , Cilostazol/administração & dosagem , Imageamento por Ressonância Magnética , Substância Branca , Idoso , Idoso de 80 Anos ou mais , Aspirina/efeitos adversos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Doenças de Pequenos Vasos Cerebrais/complicações , Cilostazol/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Substância Branca/irrigação sanguínea , Substância Branca/diagnóstico por imagem
2.
Int J Mol Sci ; 23(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35955451

RESUMO

The presence of protein inclusions, called Lewy bodies (LBs) and Lewy neurites (LNs), in the brain is the main feature of Parkinson's disease (PD). Recent evidence that the prion-like propagation of α-synuclein (α-syn), as a major component of LBs and LNs, plays an important role in the progression of PD has gained much attention, although the molecular mechanism remains unclear. In this study, we evaluated whether neuronal ApoE regulates the cell-to-cell transmission of α-syn and explored its molecular mechanism using in vitro and in vivo model systems. We demonstrate that neuronal ApoE deficiency attenuates both α-syn uptake and release by downregulating LRP-1 and LDLR expression and enhancing chaperone-mediated autophagy activity, respectively, thereby contributing to α-syn propagation. In addition, we observed that α-syn propagation was attenuated in ApoE knockout mice injected with pre-formed mouse α-syn fibrils. This study will help our understanding of the molecular mechanisms underlying α-syn propagation.


Assuntos
Apolipoproteínas E/metabolismo , Doença de Parkinson , alfa-Sinucleína/metabolismo , Animais , Apolipoproteínas E/genética , Corpos de Lewy/metabolismo , Camundongos , Neurônios/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , alfa-Sinucleína/genética
3.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445110

RESUMO

Epidermal growth factor receptor (EGFR) is overexpressed in lung cancer patients. Despite treatment with various EGFR tyrosine kinase inhibitors, recurrence and metastasis of lung cancer are inevitable. Docetaxel (DTX) is an effective conventional drug that is used to treat various cancers. Several researchers have studied the use of traditional herbal medicine in combination with docetaxel, to improve lung cancer treatment. SH003, a novel herbal mixture, exerts anticancer effects in different cancer cell types. Here, we aimed to investigate the apoptotic and anticancer effects of SH003 in combination with DTX, in human non-small-cell lung cancer (NSCLC). SH003, with DTX, induced apoptotic cell death, with increased expression of cleaved caspases and cleaved poly (ADP-ribose) polymerase in NSCLC cells. Moreover, SH003 and DTX induced the apoptosis of H460 cells via the suppression of the EGFR and signal transducer and activator of transcription 3 (STAT3) signaling pathways. In H460 tumor xenograft models, the administration of SH003 or docetaxel alone diminished tumor growth, and their combination effectively killed cancer cells, with increased expression of apoptotic markers and decreased expression of p-EGFR and p-STAT3. Collectively, the combination of SH003 and DTX may be a novel anticancer strategy to overcome the challenges that are associated with conventional lung cancer therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Docetaxel/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células A549 , Angelica , Inibidores da Angiogênese/farmacologia , Animais , Apoptose/efeitos dos fármacos , Astrágalo , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Fator de Transcrição STAT3/metabolismo , Trichosanthes , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
4.
Plant Mol Biol ; 96(1-2): 17-34, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29086189

RESUMO

KEY MESSAGE: This work suggests 2020 potential candidates in rice for the functional annotation of unannotated genes using meta-analysis of anatomical samples derived from microarray and RNA-seq technologies and this information will be useful to identify novel morphological agronomic traits. Although the genome of rice (Oryza sativa) has been sequenced, 14,365 genes are considered unannotated because they lack putative annotation information. According to the Rice Genome Annotation Project Database ( http://rice.plantbiology.msu.edu/ ), the proportion of functionally characterized unannotated genes (0.35%) is quite limited when compared with the approximately 3.9% of annotated genes with assigned putative functions. Researchers require additional information to help them investigate the molecular mechanisms associated with those unannotated genes. To determine which of them might regulate morphological or physiological traits in the rice genome, we conducted a meta-analysis of expression data that covered a wide range of tissue/organ samples. Overall, 2020 genes showed cultivar-, tissue-, or organ-preferential patterns of expression. Representative candidates from featured groups were validated by RT-PCR, and the GUS reporter system was used to validate the expression of genes that were clustered according to their leaf or root preference. Taking a molecular and genetics approach, we examined meta-expression data and found that 127 genes were differentially expressed between japonica and indica rice cultivars. This is potentially significant for future agronomic applications. We also used a T-DNA insertional mutant and performed a co-expression network analysis of Sword shape dwarf1 (SSD1), a gene that regulates cell division. This network was refined via RT-PCR analysis. Our results suggested that SSD1 represses the expression of four genes related to the processes of DNA replication or cell division and provides insight into possible molecular mechanisms. Together, these strategies present a valuable tool for in-depth characterization of currently unannotated genes.


Assuntos
Anotação de Sequência Molecular/métodos , Oryza/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Alzheimer Dis Assoc Disord ; 31(1): 13-18, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28030437

RESUMO

Laboratory-specific reference values for cerebrospinal fluid (CSF) Alzheimer disease (AD) biomarkers are necessary. Our objective was to apply well-known CSF biomarkers and redetermine their diagnostic cutoff values for AD in South Korea. CSF samples from matched control subjects (n=71), patients with AD dementia (ADD, n=76), and other neurological disorders with cognitive decline (OND, n=47) were obtained from 6 Korean dementia clinics according to a standardized protocol. CSF biomarker concentrations were measured using enzyme-linked immunosorbent assay. CSF biomarkers differed significantly between the ADD and control groups (P<0.001 for all), and between the ADD and OND groups (P<0.001 for all). The areas under the curve in differentiation of ADD from control subjects were 0.97 for Aß42, 0.93 for total tau (tTau), 0.86 for pTau, and 0.99 for both tTau/Aß42 and pTau/Aß42 ratios. Our revised cutoff value for Aß42 was higher than our previous one, whereas the values for the Tau proteins were similar. The tTau/Aß42 ratio had the highest accuracy, 97%. Our findings highlight the usefulness of CSF AD biomarkers in South Korea, and the necessity of continually testing the reliability of cutoff values.


Assuntos
Doença de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Transtornos Cognitivos/diagnóstico , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Proteínas tau/líquido cefalorraquidiano
6.
J Geriatr Psychiatry Neurol ; 30(3): 170-177, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28421896

RESUMO

BACKGROUND: We investigated differences in the prevalence of anosognosia and neuropsychiatric symptoms (NPSs) characteristics according to disease severity in patients with early-onset Alzheimer disease (EOAD). METHODS: We recruited 616 patients with EOAD. We subdivided participants into 2 groups based on the presence or absence of anosognosia and then again by Clinical Dementia Rating (CDR) scale. We compared the differences in the Neuropsychiatric Inventory (NPI) scores according to anosognosia and disease severity. RESULTS: The percentage of patients with anosognosia in each CDR group steadily increased as the CDR rating increased (CDR 0.5 8.6% vs CDR 1 13.6% vs CDR 2 26.2%). The NPI total score was significantly higher in patients with anosognosia in the CDR 0.5 and 1 groups; by contrast, it had no association in the CDR 2 group. Frontal lobe functions were associated with anosognosia only in the CDR 0.5 and 1 groups. After stratification by CDR, in the CDR 0.5 group, the prevalence of agitation ( P = .040) and appetite ( P = .013) was significantly higher in patients with anosognosia. In the CDR 1 group, patients with anosognosia had a significantly higher prevalence of delusions ( P = .032), hallucinations ( P = .048), and sleep disturbances ( P = .047). In the CDR 2 group, we found no statistical difference in the frequency of symptoms between patients with and without anosognosia. CONCLUSION: These results confirm that the prevalence of anosognosia as well as the individual NPS and cognitive functions associated with it differ according to EOAD severity.


Assuntos
Agnosia/psicologia , Doença de Alzheimer/psicologia , Afeto , Agnosia/diagnóstico , Agnosia/epidemiologia , Agnosia/fisiopatologia , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/fisiopatologia , Apetite , Cognição , Delusões/epidemiologia , Feminino , Lobo Frontal/fisiopatologia , Alucinações/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Prevalência , Transtornos do Sono-Vigília/epidemiologia
7.
J Korean Med Sci ; 32(2): 371-376, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28049252

RESUMO

Methanol poisoning results in neurological complications including visual disturbances, bilateral putaminal hemorrhagic necrosis, parkinsonism, cerebral edema, coma, or seizures. Almost all reported cases of methanol poisoning are caused by oral ingestion of methanol. However, recently there was an outbreak of methanol poisoning via non-oral exposure that resulted in severe neurological complications to a few workers at industrial sites in Korea. We present 3 patients who had severe neurological complications resulting from non-oral occupational methanol poisoning. Even though initial metabolic acidosis and mental changes were improved with hemodialysis, all of the 3 patients presented optic atrophy and ataxia or parkinsonism as neurological complications resulting from methanol poisoning. In order to manage it adequately, as well as to prevent it, physicians should recognize that methanol poisoning by non-oral exposure can cause neurologic complications.


Assuntos
Ataxia/diagnóstico , Metanol/intoxicação , Atrofia Óptica/diagnóstico , Transtornos Parkinsonianos/diagnóstico , Acidose/diagnóstico , Acidose/etiologia , Adulto , Ataxia/etiologia , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Exposição Ocupacional , Atrofia Óptica/etiologia , Transtornos Parkinsonianos/etiologia , República da Coreia , Tomografia de Coerência Óptica
8.
Biochem Biophys Res Commun ; 478(1): 286-292, 2016 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-27425247

RESUMO

Epidemiologic studies indicate that chronic use of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with a lower risk for developing Alzheimer's disease (AD). Because the primary mode of action of NSAIDs is to inhibit cyclooxygenase (COX) activity, it has been proposed that perturbed activity of COX-1 or COX-2 contributes to AD pathogenesis. To test the role of COX-1 or COX-2 in amyloid deposition and amyloid-associated inflammatory changes, we examined amyloid precursor protein (APP) transgenic mice in the context of either COX-1 or COX-2 deficiency. Our studies showed that loss of either COX-1 or COX-2 gene did not alter amyloid burden in brains of the APP transgenic mice. However, one marker of microglial activation (CD45) was decreased in brains of COX-1 deficient/APP animals and showed a strong trend in reduction in COX-2 deficient/APP animals. These results suggest that COX activity and amyloid deposition in brain are likely independent processes. Further, if NSAIDs do causally reduce the risks of AD, then our findings indicate that the mechanisms are likely not due primarily to their inhibition on COX or γ-secretase modulation activity, the latter reported recently after acute dosing of ibuprofen in humans and nonhuman primates.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/metabolismo , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Proteínas de Membrana/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 2/genética , Feminino , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/metabolismo , Distribuição Tecidual
9.
Psychother Psychosom ; 85(4): 198-207, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27230861

RESUMO

BACKGROUND: We examined the efficacy of group-based cognitive intervention (GCI) and home-based cognitive intervention (HCI) in amnestic mild cognitive impairment (aMCI) and intervention effects on serum brain-derived neurotrophic factor (BDNF). METHODS: In this randomized and rater-blinded trial, 293 patients with aMCI from 18 nationwide hospitals were randomized: 96 to the GCI group, 98 to the HCI group and 99 to the control group. For 12 weeks, subjects receiving GCI participated twice per week in group sessions led by trained instructors, and those receiving HCI completed homework materials 5 days per week. They were assessed at baseline, postintervention (PI) and at the 6-month follow-up after the intervention. The primary endpoint was the change from baseline to PI in the modified Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog). RESULTS: In comparison to the controls (a 0.8-point decrease), the subjects receiving GCI (a 2.3-point decrease, p = 0.01) or HCI (a 2.5-point decrease, p = 0.02) showed significant improvements in the modified ADAS-Cog at PI, respectively. By the 6-month follow-up, those receiving GCI or HCI had better scores in the modified ADAS-Cog than the controls. The changes in BDNF levels significantly correlated with the changes in the modified ADAS-Cog in the GCI (r = -0.29, p = 0.02 at PI) and HCI (r = -0.27, p = 0.03 at 6-month follow-up) groups, respectively. CONCLUSIONS: The GCI and HCI resulted in cognitive improvements in aMCI. An enhanced brain plasticity may be a component of the mechanism underpinning the cognitive improvements associated with the cognitive interventions.


Assuntos
Amnésia/terapia , Fator Neurotrófico Derivado do Encéfalo/sangue , Terapia Cognitivo-Comportamental/métodos , Disfunção Cognitiva/terapia , Psicoterapia de Grupo/métodos , Autocuidado/métodos , Idoso , Idoso de 80 Anos ou mais , Cognição , Terapia Cognitivo-Comportamental/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , República da Coreia , Método Simples-Cego , Resultado do Tratamento
10.
Int J Geriatr Psychiatry ; 30(6): 551-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25060738

RESUMO

OBJECTIVE: Insulin resistance (IR) is a distinct and early feature of type 2 diabetes mellitus and metabolic syndrome. IR is thought to play a vital role in cognitive impairment. We conducted this study to understand the early characteristics of cognitive dysfunctions attributable to IR. METHODS: This study included 85 consecutive non-diabetic elderly participants with mild cognitive impairment (MCI). IR was estimated with the homeostasis model assessment of insulin resistance (HOMA-IR). Cognitive performances were analyzed as a function of scores on the HOMA-IR. RESULTS: The group analysis those with and without IR did not show any differences in the cognitive performance although higher HOMA-IR was closely associated with lower performances in immediate recall on the Seoul Verbal Learning Test (SVLT-I) (r = -0.244, p = 0.026) and Controlled Oral Word Association Test (COWAT) (r = -0.270, p = 0.013). In subgroup analysis by APOE status, SVLT-delayed (p = 0.027) and COWAT (p = 0.016) scores were found to be significantly lower in the IR than the non-IR among those with APOE ε4 allele. In multiple regression analysis, impairment on the COWAT remained significantly correlated with scores on HOMA-IR (ß = -0.271, t = -2.340, p = 0.022). However, IR status was identified to interact with APOE ε4 carriership toward poor performances in the COWAT (ß = -0.335, t = -2.285, p = 0.026). CONCLUSION: This study found a domain-specific impact of HOMA-IR scores on cognitive performances in non-diabetic patients with MCI. This association was profound only in APOE ε4carriers.


Assuntos
Cognição/fisiologia , Disfunção Cognitiva/fisiopatologia , Resistência à Insulina/fisiologia , Idoso , Idoso de 80 Anos ou mais , Apolipoproteína E4/genética , Disfunção Cognitiva/genética , Feminino , Homeostase , Humanos , Masculino , Modelos Biológicos , Testes Neuropsicológicos , Análise de Regressão
11.
Compr Psychiatry ; 62: 114-22, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26343475

RESUMO

BACKGROUND: Women are subject to a disproportionate burden from Alzheimer's disease (AD) and sex differences exist in treatment response and prognosis of the disease. Yet gender-specific risk factors have not been widely studied. We aimed to investigate gender-specific risk factors for AD in subjects with mild cognitive impairment (MCI). METHODS: Participants (n=294) with MCI were recruited from a nationwide, prospective cohort study of dementia and were followed for a median (range) of 13.8 (6.0-36.0) months. Sex-stratified associations of progression to AD with baseline characteristics were explored. RESULTS: Seventy-four individuals (25.2%) developed incident dementia (67 AD) during follow-up. Significant risk factors for probable AD differed by sex. In men, the significant risk factors were severe periventricular white matter hyperintensities, and poorer global cognitive function. In women, older age, clinically significant depressive symptoms at baseline, and positive APOE ε4 alleles were the significant risk factors. CONCLUSIONS: Risk factors for progression from MCI to probable AD differed in men and women. These results may translate to gender-specific preventative or therapeutic strategies for patients with MCI.


Assuntos
Doença de Alzheimer/psicologia , Disfunção Cognitiva/psicologia , Progressão da Doença , Idoso , Doença de Alzheimer/etiologia , Doença de Alzheimer/patologia , Cognição , Disfunção Cognitiva/patologia , Demência , Feminino , Humanos , Masculino , Estudos Prospectivos , República da Coreia , Fatores de Risco , Fatores Sexuais
12.
BMC Neurol ; 14: 66, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24690253

RESUMO

BACKGROUND: We investigated levels of the ß-amyloid 1-42 (Aß42), total tau protein (T-tau) and tau phosphorylated at position threonine 181 (P-tau) in cerebrospinal fluid (CSF) of idiopathic normal pressure hydrocephalus (iNPH) patients and tried to find their clinical implications in the evaluation and treatment of iNPH. METHOD: Twenty-five possible iNPH patients were prospectively enrolled and their CSF was collected to analyze levels of Aß42, T-tau and P-tau using ELISA method. Gait disturbance, urinary incontinence, and cognitive impairment were semi-quantified and detailed neuropsychological (NP) test was performed. RESULT: Eight iNPH patients were classified into the lower CSF Aß42 group and 17 patients were classified into the higher CSF Aß42 group. There was no difference in the iNPH grading score and its improvement after LP between the two groups. The lower CSF Aß42 group showed more deficits in attention, visuospatial function and verbal memory in the baseline NP test and less improvement in phonemic categorical naming and frontal inhibitory function after LP. CONCLUSIONS: Our study suggested that concomitant AD in iNPH patients might contribute to lumbar puncture or shunt unresponsiveness, especially in the field of cognitive dysfunction.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/complicações , Hidrocefalia de Pressão Normal/líquido cefalorraquidiano , Hidrocefalia de Pressão Normal/complicações , Idoso , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Encéfalo/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Hidrocefalia de Pressão Normal/patologia , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Proteínas tau/líquido cefalorraquidiano
13.
J Alzheimers Dis ; 97(1): 485-506, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38108353

RESUMO

BACKGROUND: Obesity is a modifiable risk factor for Alzheimer's disease (AD). However, its relation with tau pathology (i.e., aberrant tau protein behavior in tauopathies such as AD) has been inconclusive. OBJECTIVE: This study investigated the interaction between a high-fat diet (HFD) and tau pathology in adult male mice. METHODS: Transgenic mice overexpressing human P301S Tau (those with the pathology) and wild-type (WT) littermates were subjected to behavioral tests, functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), and western blotting analysis to investigate the effects of prolonged HFD versus regular diet during adulthood. RESULTS: HFD increased body weight in both WT and P301S mice but had minimal effect on blood glucose levels. The brain response to HFD was tau genotype-specific. WT mice exhibited decreased recognition memory and enhanced network connectivity in fMRI, while P301S mice exhibited white matter tract disorganization in DTI as the sole significant finding. The reduction of insulin receptor ß, insulin downstream signaling, neuronal nuclear protein, CD68-positive phagocytic activity, and myelin basic protein level were confined to the cortex of WT mice. In contrast to P301S mice, WT mice showed significant changes in the tau protein and its phosphorylation levels along with increased soluble neurofilament light levels in the hippocampus. CONCLUSIONS: HFD-induced brain dysfunction and pathological changes were blunted in mice with the pathology and more profound in healthy mice. Our findings highlight the need to consider this interaction between obesity and tau pathology when tailoring treatment strategies for AD and other tauopathies.


Assuntos
Doença de Alzheimer , Tauopatias , Camundongos , Masculino , Humanos , Animais , Adulto , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Dieta Hiperlipídica/efeitos adversos , Imagem de Tensor de Difusão , Tauopatias/patologia , Camundongos Transgênicos , Obesidade/diagnóstico por imagem , Obesidade/genética
14.
Nat Commun ; 14(1): 8463, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123547

RESUMO

Brain endothelial LDL receptor-related protein 1 (LRP1) is involved in the clearance of Aß peptides across the blood-brain barrier (BBB). Here we show that endothelial deficiency of ankyrin repeat and SAM domain containing 1 A (ANKS1A) reduces both the cell surface levels of LRP1 and the Aß clearance across the BBB. Association of ANKS1A with the NPXY motifs of LRP1 facilitates the transport of LRP1 from the endoplasmic reticulum toward the cell surface. ANKS1A deficiency in an Alzheimer's disease mouse model results in exacerbated Aß pathology followed by cognitive impairments. These deficits are reversible by gene therapy with brain endothelial-specific ANKS1A. In addition, human induced pluripotent stem cell-derived BBBs (iBBBs) were generated from endothelial cells lacking ANKS1A or carrying the rs6930932 variant. Those iBBBs exhibit both reduced cell surface LRP1 and impaired Aß clearance. Thus, our findings demonstrate that ANKS1A regulates LRP1-mediated Aß clearance across the BBB.


Assuntos
Células-Tronco Pluripotentes Induzidas , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Animais , Humanos , Camundongos , Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Células Endoteliais/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo
15.
J Neurochem ; 123(5): 856-65, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23020770

RESUMO

Caspase cleavage of amyloid precursor protein (APP) has been reported to be important in amyloid beta protein (Aß)-mediated neurotoxicity. However, the underlying mechanisms are not clearly understood. In this study, we explored the effect of caspase cleavage of APP on tau phosphorylation in relation to Aß. We found that Asp664 cleavage of APP increased tau phosphorylation at Thr212 and Ser262 in N2A cells and primary cultured hippocampal neurons. Compared with wild-type APP, protein phosphatase 2A (PP2A) activity was significantly increased when Asp664 cleavage was blocked by the D664A point mutation. Furthermore, we found that over-expression of C31 reduced PP2A activity. C31 binds directly to the PP2A catalytic subunit, through the asparagine, proline, threonine, tyrosine (NPTY) motif, which is essential for C31-induced tau hyperphosphorylation. However, it appears that the other fragment produced by Asp664 cleavage, Jcasp, modulates neither PP2A activity nor tau hyperphosphorylation. Asp664 cleavage and accompanying tau hyperphosphorylation were remarkably diminished by blockage of Aß production using a γ-secretase inhibitor. Taken together, our results suggest that Asp664 cleavage of APP leads to tau hyperphosphorylation at specific epitopes by modulating PP2A activity as a downstream of Aß. Direct binding of C31 to PP2A through the C31-NPTY domain was identified as a mechanism underlying this effect.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Proteína Fosfatase 2/metabolismo , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Western Blotting , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Imuno-Histoquímica , Camundongos , Fosforilação , Ratos , Transfecção
16.
J Clin Neurol ; 18(4): 401-409, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35796265

RESUMO

Alzheimer's disease (AD) is the most-common cause of neurodegenerative dementia, and it is characterized by abnormal amyloid and tau accumulation, which indicates neurodegeneration. AD has mostly been diagnosed clinically. However, ligand-specific positron emission tomography (PET) imaging, such as amyloid PET, and cerebrospinal fluid (CSF) biomarkers are needed to accurately diagnose AD, since they supplement the shortcomings of clinical diagnoses. Using biomarkers that represent the pathology of AD is essential (particularly when disease-modifying treatment is available) to identify the corresponding pathology of targeted therapy and for monitoring the treatment response. Although imaging and CSF biomarkers are useful, their widespread use is restricted by their high cost and the discomfort during the lumbar puncture, respectively. Recent advances in AD blood biomarkers shed light on their future use for clinical purposes. The amyloid ß (Aß)42/Aß40 ratio and the concentrations of phosphorylated tau at threonine 181 and at threonine 217, and of neurofilament light in the blood were found to represent the pathology of Aß, tau, and neurodegeneration in the brain when using automatic electrochemiluminescence technologies, single-molecule arrays, immunoprecipitation coupled with mass spectrometry, etc. These blood biomarkers are imminently expected to be incorporated into clinical practice to predict, diagnose, and determine the stage of AD. In this review we focus on advancements in the measurement technologies for blood biomarkers and the promising biomarkers that are approaching clinical application. We also discuss the current limitations, the needed further investigations, and the perspectives on their use.

17.
Exp Neurobiol ; 31(3): 196-207, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35786641

RESUMO

Circadian disruption often involves a neurodegenerative disorder, such as Alzheimer's disease or frontotemporal dementia, which are characterized by intraneuronal tau accumulations. The altered sleep pattern and diurnal rhythms in these disorders are the results of tau pathology. The circadian disturbance in reverse is thought to develop and potentially aggravate the condition. However, the underlying mechanism is not fully understood. In this study, perturbed oscillations in BMAL1 , the core clock gene, were observed in P301S tau transgenic mice. Tau fractionation analysis of the hippocampus revealed profound fluctuations in soluble and insoluble tau protein levels that were in opposite directions to each other according to zeitgeber time. Interestingly, a diurnal oscillation was detected in the heat shock 70 kDa protein 1A (Hsp70) chaperone that was in-phase with soluble tau but out-of-phase with insoluble tau. Tau protein levels decreased in the soluble and insoluble fractions when Hsp70 was overexpressed in HEK293T cells. Transfection of the BMAL1 carrying vector was continual with the increase in Hsp70 expression and diminished tau protein levels, and it was effectively attenuated by the knockdown of Hsp70, suggesting that Bmal1 could modulate tau protein by Hsp70. Our results suggest that altered circadian oscillations affect tau status and solubility by modulating Hsp70 expression in an experimental model of tau pathology. These findings suggest Hsp70 as a possible pathogenic link between circadian disruption and aggravations of tau pathology.

18.
IEEE Trans Biomed Eng ; 69(1): 199-208, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34156933

RESUMO

OBJECTIVE: Focused ultrasound has been applied in brain therapeutics. Although focusing ultrasonic beams on multiple arbitrary regions under the guidance of magnetic resonance imaging(MRI) is needed for precise treatments, current therapeutic transducers with large pitch sizes have been optimized to focus on deep brain regions. While annular arrays can adjust the beam foci from cortical to deep regions, their circular shape may generate eddy current-induced magnetic flux during MRI. In this study, a quadrisected annular array is proposed to address these limitations. METHODS: Conventional and quadrisected annular arrays with three elements were implemented by loading the electrode patterns onto an 850 kHz 1-3 composite PZT disc, with a diameter of 31 mm, including three rings. MR compatibilities were demonstrated by imaging an MRI phantom with pulse sequences for B0 and B1 mapping and spin-echo imaging. Acoustic beam profiles, with and without a macaque monkey skull, were measured. A quadrisected transducer was also used to open the blood-brain barrier(BBB). RESULTS: The flip angle distortion improved by 20% in spin-echo MR imaging. The acoustic beam distortions shifting the focal point from 36 to 41mm and elongating the focal zone from 10 to 15 mm could be recovered to nearly the original values. BBB openings in the hippocampus and basal region were also demonstrated. CONCLUSION: The MR compatibility was improved by the increased resistance of the electrodes in the quadrisected array maintaining dynamic focusing capabilities. SIGNIFICANCE: The quadrisected annular design can be a fundamental structure for a larger MR-compatible segmented array transducer generating multiple acoustic foci.


Assuntos
Imageamento por Ressonância Magnética , Transdutores , Encéfalo/diagnóstico por imagem , Espectroscopia de Ressonância Magnética , Imagens de Fantasmas
19.
Biosens Bioelectron ; 209: 114279, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35447599

RESUMO

Alzheimer's disease (AD), one of the leading senile disorders in the world, causes severe memory loss and cognitive impairment. To date, there is no clear cure for AD. However, early diagnosis and monitoring can help mitigate the effects of this disease. In this study, we reported a platform for diagnosing early-stage AD using microRNAs (miRNAs) in the blood as biomarkers. First, we selected an appropriate target miRNA (miR-574-5p) using AD model mice (4-month-old 5XFAD mice) and developed a hydrogel-based sensor that enabled high-sensitivity detection of the target miRNA. This hydrogel contained catalytic hairpin assembly (CHA) reaction-based probes, leading to fluorescence signal amplification without enzymes and temperature changes, at room temperature. This sensor exhibited high sensitivity and selectivity, as evidenced by its picomolar-level detection limit (limit of detection: 1.29 pM). Additionally, this sensor was evaluated using the plasma of AD patients and non-AD control to validate its clinical applicability. Finally, to use this sensor as a point-of-care-testing (POCT) diagnostic system, a portable fluorometer was developed and verified for feasibility of application.


Assuntos
Doença de Alzheimer , Técnicas Biossensoriais , MicroRNAs , Animais , Diagnóstico Precoce , Humanos , Hidrogéis , Camundongos , MicroRNAs/genética
20.
Perspect Psychiatr Care ; 57(3): 989-999, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33052599

RESUMO

PURPOSE: To identify factors influencing the hopes of mental health nurses and to explore their experiences with a sense of hope. DESIGN AND METHODS: A descriptive research survey was conducted with 113 nurses at three closed psychiatric wards in South Korea. FINDINGS: Nurses' hope, interpersonal skill competence, and professional self-concept were all found to have statistically significant correlations (r = 0.60-0.73, p < 0.01). These factors explained 62% of the variance in nurses' hope. In ten themes influencing hope, 71.1% were positive, 28.9% negative. PRACTICE IMPLICATIONS: The findings suggest that the promotion of nurses' interpersonal skill competence and professional self-concept is helpful for increasing hope levels. Both positive and negative experiences with hope are important in developing strategies of nursing roles.


Assuntos
Transtornos Mentais , Enfermeiras e Enfermeiros , Enfermagem Psiquiátrica , Esperança , Humanos , Transtornos Mentais/terapia , República da Coreia
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