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1.
Alzheimers Dement ; 19(10): 4641-4650, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36988152

RESUMO

BACKGROUND: A combination of plasma phospho-tau (p-tau), amyloid beta (Aß)-positron emission tomography (PET), brain magnetic resonance imaging, cognitive function tests, and other biomarkers might predict future cognitive decline. This study aimed to investigate the efficacy of combining these biomarkers in predicting future cognitive stage transitions within 3 years. METHODS: Among the participants in the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease (KBASE-V) study, 49 mild cognitive impairment (MCI) and 113 cognitively unimpaired (CU) participants with Aß-PET and brain imaging data were analyzed. RESULTS: Older age, increased plasma p-tau181, Aß-PET positivity, and decreased semantic fluency were independently associated with cognitive stage transitions. Combining age, p-tau181, the Centiloid scale, semantic fluency, and hippocampal volume produced high predictive value in predicting future cognitive stage transition (area under the curve = 0.879). CONCLUSIONS: Plasma p-tau181 and Centiloid scale alone or in combination with other biomarkers, might predict future cognitive stage transition in non-dementia patients. HIGHLIGHTS: -Plasma p-tau181 and Centiloid scale might predict future cognitive stage transition. -Combining them or adding other biomarkers increased the predictive value. -Factors that independently associated with cognitive stage transition were demonstrated.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Peptídeos beta-Amiloides , Proteínas tau , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Cognição , Disfunção Cognitiva/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Biomarcadores
2.
Anal Biochem ; 609: 113921, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32828793

RESUMO

Alzheimer's disease (AD) causes cognitive impairment and serious social isolation. However, there are no effective treatments and even no established confirmatory diagnostic tools for the disease. Amyloid beta (Aß) aggregation in the brain is the best-known pathognomonic mechanism of AD, so various methods for Aß detection have been developed for the diagnosis of this disease. We synthesized two novel, ultra-sensitive peptide probes specialized in detecting Aß aggregates, and examined their potential for future diagnostic application. The peptides are produced through phage high-throughput screening (HTS) and amplified through a serial process called biopanning, which is a repeating method of elution and amplification of probes. We picked phages specific for amyloid from two kinds of phage display. The synthesized peptides were confirmed to have excellent binding affinity to Aß aggregates, by immunohistochemical staining and western blotting using the brains of 3X transgenic (Tg) AD mice at different stages (5-7, 12-17 months old) of AD severity. In the present study, it was confirmed that newly developed amyloid-binding peptides could be used as novel probes for the detection of Aß aggregates, which can be used for clinical diagnosis of AD in the future.


Assuntos
Peptídeos beta-Amiloides/análise , Aptâmeros de Peptídeos/metabolismo , Fragmentos de Peptídeos/análise , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Aptâmeros de Peptídeos/química , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Biblioteca de Peptídeos , Agregados Proteicos/fisiologia , Ligação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Índice de Gravidade de Doença
3.
Clin Exp Ophthalmol ; 48(5): 624-635, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32173975

RESUMO

IMPORTANCE: Micro-RNAs (miRNAs) have been studied as new biomarkers or mediators in various diseases, but the value of aqueous humour (AH) miRNAs in diabetic macular oedema (DMO) is still not known. BACKGROUND: To compare AH miRNAs and related cytokine expression in DMO patients and healthy controls. DESIGN: Prospective cross-sectional study. PARTICIPANTS: Twenty naïve DMO patients and 13 control subjects, who were scheduled for intravitreal injection and cataract surgery, respectively. METHODS: AH samples were collected at the beginning of each procedure and analysed using a miRNA polymerase chain reaction (PCR) array composed of 84 miRNAs, reverse transcripase-quantitative PCR (qPCR) for verifying selected differentially expressed miRNAs, and a cytokine assay, the results of which were compared with bioinformatics conducted to find out genes associated with DMO-related miRNAs. MAIN OUTCOMES MEASURES: AH expression of miRNAs and cytokines and the bioinformatics results. RESULTS: Five miRNAs (hsa-miR-185-5p, hsa-miR-17-5p, hsa-miR-20a-5p, hsa-miR-15b-5p and hsa-miR-15a-5p) showing a fold change greater than -50 in log2 values in the miRNA PCR array were selected, all significantly down-regulated in the DMO group compared to the control group (P < .05), and showed a direct relationship with tumour necrosis factor, nuclear factor kappa B subunit 1 and interleukin-6 (IL-6) in bioinformatics analysis, all of which were related to vascular endothelial growth factor (VEGF). In the cytokine assay, the aqueous concentrations of VEGF, placental growth factor, IL-6 and IL-8 were significantly higher in the DMO group compared to the control group. CONCLUSIONS AND RELEVANCE: This study is the first to perform miRNA profiling of the AH of DMO patients. We identified differentially expressed miRNAs in DMO AH, which may be used as potential biomarkers or novel therapeutic targets for DMO.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , MicroRNAs , Humor Aquoso , Estudos Transversais , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Edema Macular/diagnóstico , Edema Macular/genética , MicroRNAs/genética , Fator de Crescimento Placentário , Estudos Prospectivos , Fator A de Crescimento do Endotélio Vascular
4.
Anal Chem ; 91(9): 5573-5581, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30938150

RESUMO

Amyloid-beta 42 (Aß42), the key biomarker of Alzheimer's disease (AD), aggregates to form neurotoxic amyloid plaques. In this work, we modified two fluorescein isothiocyanate-labeled Aß42-targeting peptides and designed an Aß42-specific ultrasensitive polyvalent-directed peptide polymer (PDPP) to enhance AD diagnosis sensitivity. The dissociation constant of Aß42 by PDPP was 103-fold higher than the single-site-directed peptide. The improved binding was due to the ability of PDPP to detect multiple receptors on the target. The power of the PDPP diagnostic probe was verified in its application to detect Aß42 in cerebrospinal fluid (CSF), which showed a lower limit of detection (LOD) in the fg mL-1 range that is more sensitive than detection by antibodies or single peptides. In addition, we present a novel ultrasensitive diagnostic system using an array of nanoporous ZnO nanoparticles, which play a role in fluorescence signal amplification, to further improve AD diagnosis sensitivity. We enhanced the signal on the basis of the properties of nanoporous ZnO nanoparticles and measured and quantified an ultralow concentration (ag mL-1 range) of Aß42. This PDPP coupled to the nanoporous ZnO-based system is a novel approach to AD diagnosis that might also be useful for the detection of other target biomarkers and clinical applications.


Assuntos
Doença de Alzheimer/diagnóstico , Limite de Detecção , Nanoporos , Peptídeos/química , Peptídeos/metabolismo , Óxido de Zinco/química , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/metabolismo , Sequência de Aminoácidos , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Diatrizoato/análogos & derivados , Humanos , Isotiocianatos/química , Camundongos , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fragmentos de Peptídeos/metabolismo , Espectrometria de Fluorescência
5.
Cell Biol Toxicol ; 34(3): 219-232, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28965180

RESUMO

Cerebral infarction causes severe morbidity and mortality. Most patients with cerebral infarction should take antiplatelet drugs daily, so the effects of those drugs on the regeneration of the brain need to be investigated. Aspirin and clopidogrel are the most widely used antiplatelet drugs for the prevention of ischemic stroke. We investigated the effects of aspirin and clopidogrel on neural stem cells (NSCs). NSCs were dissociated from fetal rat cortex and cultured with basic fibroblast growth factor and N2 medium. To measure the effects of aspirin and clopidogrel on NSCs, NSCs were treated with several concentrations of aspirin, clopidogrel bisulfate, and clopidogrel resinate for 24 h. After the treatment, we measured cell viability by cell counting kit-8, MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay, trypan blue staining, flow cytometry, and lactate dehydrogenase assay. To evaluate their effects on NSC proliferation, we performed BrdU cell proliferation assay and colony-forming unit assay. We compared the intracellular protein level in the NSCs treated with aspirin and two types of clopidogrel, by proteomics analysis. Various viability tests showed that clopidogrel resinate and clopidogrel bisulfate did not affect the viability and proliferation of NSCs whereas aspirin decreased them even at low concentrations which are clinically relevant. Moreover, through the proteomics, it was confirmed that the toxicity of aspirin to NSCs might be associated with the alteration of several intracellular proteins. Taken together, these results suggest that clopidogrel resinate and clopidogrel bisulfate are safe but aspirin could be toxic to NSCs. Therefore, when these antiplatelet agents are prescribed over the long-term, the finding that aspirin could be toxic to NSCs should be considered.


Assuntos
Aspirina/farmacologia , Clopidogrel/farmacologia , Células-Tronco Neurais/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Eletroforese em Gel Bidimensional , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Ratos
6.
J Neurochem ; 135(1): 186-93, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26222278

RESUMO

Cerebral infarction causes permanent neuronal loss inducing severe morbidity and mortality. Because hypertension is the main risk factor for cerebral infarction and most patients with hypertension take antihypertensive drugs daily, the neuroprotective effects and mechanisms of anti-hypertensive drugs need to be investigated. Cilnidipine, a long-acting, new generation 1,4-dihydropyridine inhibitor of both L- and N-type calcium channels, was reported to reduce oxidative stress. In this study, we investigated whether cilnidipine has therapeutic effects in an animal model of cerebral infarction. After determination of the most effective dose of cilnidipine, a total of 128 rats were subjected to middle cerebral artery occlusion. Neurobehavioral function test and brain MRI were performed, and rats with similar sized infarcts were randomized to either the cilnidipine group or the control group. Cilnidipine treatment was performed with reperfusion after 2-h occlusion. Western blots and immunohistochemistry were also performed after 24-h occlusion. Initial infarct volume on diffusion-weighted MRI was not different between the cilnidipine group and the control group; however, fluid-attenuated inversion recovery MRI at 24 h showed significantly reduced infarct volume in the cilnidipine group compared with the control group. Cilnidipine treatment significantly decreased the number of triphosphate nick end labeling-positive cells compared to the control group. Western blot and immunohistochemistry showed increased expression of phosphorylated Akt (Ser473), phosphorylated glycogen synthase kinase-3ß, and Bcl-2 and decreased expression of Bax and cleaved caspase-3. These results suggest that cilnidipine, which is used for the treatment of hypertension, has neuroprotective effects in the ischemic brain through activation of the PI3K pathway. We investigated whether cilnidipine has neuroprotective effects on ischemic stroke in an animal model. We have demonstrated that the neuroprotective effect of cilnidipine is associated with the activation of the PI3K pathway. Considering the daily use of antihypertensive drugs for patients with hypertension, cilnidipine could be beneficial for patients with ischemic stroke.


Assuntos
Encéfalo/efeitos dos fármacos , Infarto Cerebral/tratamento farmacológico , Di-Hidropiridinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Hipertensão/tratamento farmacológico , Masculino , Ratos Sprague-Dawley
7.
J Stroke Cerebrovasc Dis ; 24(3): 704-10, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25601176

RESUMO

BACKGROUND: Pre-existing silent brain infarctions (SBIs) have been reported to be associated with better outcomes after first-ever symptomatic ischemic stroke, although the mechanism of this remains unclear. We investigated the association between SBIs, outcomes of acute lacunar infarction, and biomarkers including vascular endothelial growth factor (VEGF), stromal cell-derived factor-1α (SDF-1α), macrophage migration inhibitory factor (MIF), and high-mobility group box-1 (HMGB1). METHODS: A total of 68 consecutive patients diagnosed with first-ever lacunar infarction (<20 mm) within 24 hours of symptom onset were included in this study. Clinical, laboratory, and imaging data were obtained. Plasma levels of VEGF, SDF-1α, MIF, and HMGB1 were assessed using Enzyme-Linked Immunosorbent Assay kits. RESULTS: SBIs were noted in 31 of the 68 patients. Although the initial National Institutes of Health Stroke Scale scores were not related with the presence of SBIs (P = .313), patients with SBIs had better outcomes at 3 months (P = .029). Additionally, plasma VEGF levels were higher (P = .035) and SDF-1α levels were lower (P < .001) in patients with SBIs. Logistic regression analysis indicated that VEGF and SDF-1α were independently associated with the presence of SBIs. CONCLUSIONS: SBIs are associated with favorable outcomes in patients with first-ever acute lacunar infarction and higher levels of VEGF, and lower levels of SDF-1α in these patients may contribute to their more favorable prognosis.


Assuntos
Quimiocina CXCL12/sangue , Acidente Vascular Cerebral Lacunar/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Avaliação da Deficiência , Regulação para Baixo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Acidente Vascular Cerebral Lacunar/diagnóstico , Acidente Vascular Cerebral Lacunar/etiologia , Acidente Vascular Cerebral Lacunar/terapia , Fatores de Tempo , Regulação para Cima
8.
Aging (Albany NY) ; 16(3): 1983-2004, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38301041

RESUMO

GV1001, which mimics the activity of human telomerase reverse transcriptase, protects neural cells from amyloid beta (Aß) toxicity and other stressors through extra-telomeric function, as noted in our prior in vitro studies. As per a recent phase II clinical trial, it improves cognitive function in patients with moderate to severe dementia. However, the underlying protective mechanisms remain unclear. This study aimed to investigate the effects of GV1001 on neurodegeneration, senescence, and survival in triple transgenic Alzheimer's disease (3xTg-AD) mice. GV1001 (1 mg/kg) was subcutaneously injected into old 3xTg-AD mice thrice a week until the endpoint for sacrifice, and survival was analysed. Magnetic resonance imaging (MRI) and Prussian blue staining (PBS) were performed to evaluate entry of GV1001 entrance into the brain. Diverse molecular studies were performed to investigate the effect of GV1001 on neurodegeneration and cellular senescence in AD model mice, with a particular focus on BACE, amyloid beta1-42 (Aß1-42), phosphorylated tau, volume of dentate gyrus, ß-galactosidase positive cells, telomere length, telomerase activity, and ageing-associated proteins. GV1001 crossed the blood-brain barrier, as confirmed by assessing the status of ferrocenecarboxylic acid-conjugated GV1001 using magnetic resonance imaging and PBS. GV1001 increased the survival of 3xTg-AD mice. It decreased BACE and Aß1-42 levels, neurodegeneration (i.e., reduced CA1, CA3 and dentate gyrus volume, decreased levels of senescence-associated ß-galactosidase positive cells, and increased telomere length and telomerase activity), and levels of ageing-associated proteins. We suggest that GV1001 exerts anti-ageing effects in 3xTg-AD mice by reducing neurodegeneration and senescence, which contributes to improved survival.


Assuntos
Doença de Alzheimer , Telomerase , Camundongos , Humanos , Animais , Peptídeos beta-Amiloides/metabolismo , Longevidade , Camundongos Transgênicos , Telomerase/metabolismo , Doença de Alzheimer/metabolismo , Envelhecimento , Modelos Animais de Doenças , beta-Galactosidase/metabolismo , Proteínas tau/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo
9.
Aging (Albany NY) ; 162024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39074257

RESUMO

A shorter leukocyte telomere length (LTL) is reported to be associated with age-related diseases, including osteoporosis. Many studies have tried identifying the association between LTL and osteoporosis, although it remains controversial. This study aimed to determine whether osteoporosis is independently associated with LTL shortening in a prospective longitudinal cohort. The KBASE study is an independent multicenter prospective cohort in South Korea, which began in 2014. We compared the LTL values for each participant at baseline and over a 2-year follow-up period. Boxplots were used to demonstrate the differences in the change in LTL over a 2-year follow-up according to osteoporosis. Multivariable linear regression was conducted to identify whether osteoporosis is independently associated with the rate of telomere shortening. A total of 233 subjects (from 55 to 88 years) from the KBASE cohort were finally enrolled in the study. We observed that the LTL decreased by approximately 1.2 kbp over 2 years. While the LTL decreased as age increased, the rate of LTL shortening did not increase with age. Multivariable linear regression analysis indicated that only osteoporosis was independently associated with rapid LTL shortening over 2 years (B, -8.08; p = 0.038). We sought to identify an association between osteoporosis and LTL shortening in an independent prospective cohort. We found that participants with osteoporosis had significantly faster LTL shortening over 2 years than those without osteoporosis. We hope this study will help elucidate the underlying mechanisms in the relationship between LTL and osteoporosis in the future.

10.
Aging (Albany NY) ; 15(4): 914-931, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36805537

RESUMO

Telomere length (TL) has been reported to be associated with depression and cognitive impairment in elderly. Early detection of depression and cognitive impairment is important to delay disease progression. Therefore, we aimed to identify whether TL is associated with early subjective depressive symptoms and cognitive complaints among healthy elderly subjects. This study was a multicenter, outcome assessor-blinded, 24-week, randomized controlled trial (RCT). Measurement of questionnaire and physical activity scores and blood sample analyses were performed at baseline and after six months of follow-up in all study participants. Linear regression analyses were performed to identify whether early subjective depressive symptoms, cognitive complaints, and several blood biomarkers are associated with TL. Altogether, 137 relatively healthy elderly individuals (60-79 years old) were enrolled in this prospective RCT. We observed an approximate decrease of 0.06 and 0.11-0.14 kbps of TL per one point increase in the geriatric depression scale and cognitive complaint interview scores, respectively, at baseline and after six months of follow-up. We also found an approximate decrease of 0.08-0.09 kbps of TL per one point increase in interleukin (IL)-6 levels at baseline and after six months of follow-up. Our study showed that both early subjective depressive symptoms and cognitive complaints were associated with a relatively shorter TL in relatively healthy elderly individuals. In addition, based on our findings, we believe that IL-6 plays an important role in the relationship between shortening TL and early subjective depressive symptoms and cognitive complaints.


Assuntos
Disfunção Cognitiva , Depressão , Idoso , Humanos , Cognição , Disfunção Cognitiva/psicologia , Depressão/psicologia , Inquéritos e Questionários , Telômero , Encurtamento do Telômero , Pessoa de Meia-Idade
11.
Alzheimers Dement (Amst) ; 15(4): e12502, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026758

RESUMO

Introduction: This study aimed to determine the efficacy of combining plasma phosphorylated tau (p-tau)181, amyloid beta (Aß)42/Aß40, neurofilament light (NfL), and apolipoprotein E (APOE) genotypes for detecting positive amyloid positron emission tomography (PET), which is little known in the Asian population, in two independent cohorts. Methods: Biomarkers were measured using a single-molecule array (Simoa) in a cohort study (Asan). All participants underwent amyloid PET. Significant changes in the area under the curve (AUC) and Akaike Information Criterion values were considered to determine the best model. The generalizability of this model was tested using another cohort (KBASE-V). Results: In the Asan cohort, after adjusting for age and sex, p-tau181 (AUC = 0.854) or APOE ε4 status (AUC = 0.769) distinguished Aß status with high accuracy. Combining them or adding NfL and Aß42/40 improved model fitness. The best-fit model included the plasma p-tau181, APOE ε4, NfL and Aß42/40. The models established from the Asan cohort were tested in the KBASE-V cohort. Additionally, in the KBASE-V cohort, these three biomarker models had similar AUC in cognitively unimpaired (AUC = 0.768) and mild cognitive impairment (MCI) (AUC = 0.997) participants. Conclusions: Plasma p-tau181 showed a high performance in determining Aß-PET positivity. Adding plasma NfL and APOE ε4 status improved the model fit without significant improvement in AUC.

12.
Sci Rep ; 12(1): 16429, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180575

RESUMO

The aim of this study is to investigate the differential expression of microRNAs (miRNAs) in the aqueous humor (AH) of patients with central retinal vein occlusion (CRVO), and their association with AH matrix metalloproteinase (MMP) activity. Eighteen subjects, including 10 treatment naïve patients with CRVO and 8 control subjects, scheduled for intravitreal injection and cataract surgery, respectively, were included. AH samples were collected at the beginning of the procedure. A microarray composed of 84 miRNAs was performed to identify differentially expressed miRNAs in CRVO AH, which were further analyzed using bioinformatic tools to identify directly related cytokines/proteins. Eight miRNAs (hsa-mir-16-5p, hsa-mir-142-3p, hsa-mir-19a-3p, hsa-mir-144-3p, hsa-mir-195-5p, hsa-mir-17-5p, hsa-mir-93-5p, and hsa-mir-20a-5p) were significantly downregulated in the CRVO group. Bioinformatic analysis revealed a direct relationship among downregulated miRNAs, CRVO, and the following proteins: MMP-2, MMP-9, tumor necrosis factor, transforming growth factor beta-1, caspase-3, interleukin-6, interferon gamma, and interleukin-1-beta. Activities of MMP-2 and -9 in AH were detected using gelatin zymography, showing significant increase in the CRVO group compared to the control group (p < 0.01). This pilot study first revealed that MMP-2 and -9 were directly related to downregulated miRNAs and showed significant increase in activity in AH of patients with CRVO. Therefore, the relevant miRNAs and MMPs in AH could serve as potential biomarkers or therapeutic targets for CRVO.


Assuntos
MicroRNAs , Oclusão da Veia Retiniana , Humor Aquoso/metabolismo , Biomarcadores/metabolismo , Caspase 3/metabolismo , Gelatina/metabolismo , Perfilação da Expressão Gênica , Humanos , Interferon gama/metabolismo , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Projetos Piloto , Oclusão da Veia Retiniana/genética , Oclusão da Veia Retiniana/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fatores de Necrose Tumoral/metabolismo
13.
Alzheimers Res Ther ; 14(1): 6, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996525

RESUMO

BACKGROUND: Neurofilament light chain (NFL) level has been suggested as a blood-based biomarker for neurodegeneration in dementia. However, the association between baseline NFL levels and cognitive stage transition or cortical thickness is unclear. This study aimed to investigate whether baseline NFL levels are associated with cognitive stage transition or cortical thickness in mild cognitive impairment (MCI) and cognitively unimpaired (CU) participants. METHODS: This study analyzed data on participants from the independent validation cohort of the Korea Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's disease (KBASE-V) study. Among the participants of KBASE-V study, 53 MCI and 146 CU participants who were followed up for ≥ 2 years and had data on the serum NFL levels were eligible for inclusion in this study. Participants were classified into three groups according to baseline serum NFL levels of low, middle, or high. RESULTS: The Kaplan-Meier analysis showed association between the serum NFL tertiles and risk of cognitive stage transition in MCI (P = 0.002) and CU (P = 0.028) participants, analyzed separately. The same is true upon analysis of MCI and CU participants together (P < 0.001). In MCI participants, the highest serum NFL tertile and amyloid-beta positivity were independent predictors for cognitive stage transition after adjusting for covariates. For CU participants, only amyloid-beta positivity was identified to be an independent predictor. CONCLUSION: The study shows that higher serum NFL tertile levels correlate with increased risk of cognitive stage transition in both MCI and CU participants. Serum NFL levels were negatively correlated with the mean cortical thickness of the whole-brain and specific brain regions.


Assuntos
Disfunção Cognitiva , Filamentos Intermediários , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/sangue , Biomarcadores , Cognição , Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico , Humanos
14.
Aging (Albany NY) ; 14(7): 2930-2944, 2022 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-35366243

RESUMO

BACKGROUND: The relationship between sleep parameters and longitudinal shortening of telomere length is unclear. This study aimed to investigate the relationship between sleep parameters and the shortening of leukocyte telomere length (LTL) over a year. METHODS: Among the participants in the validation cohort of the Korea Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease, participants who measured both baseline and follow-up (two years later) of LTL were analyzed. They were dichotomized according to the degree of LTL attrition over two years. Clinical characteristics were compared between the faster and slower LTL shortening groups (cut-off points: -0.710 kbp, n = 119 each). Multivariable logistic regression analyses were performed to determine independent relationships between faster shortening of LTL length and sleep parameters. RESULTS: A total of 238 participants, aged 55-88 years, were included. Participants with faster LTL shortening had a shorter duration of sleep (P = 0.013) and longer sleep latency (P = 0.007). Among the components of the PSQI, subjective measures of sleep quality, sleep latency, sleep duration, and sleep efficiency were significantly worse in participants with faster LTL shortening. Multivariate logistic regression analysis showed that sleep duration (per hour, OR = 0.831, 95% CI = 0.698-0.989), sleep latency (per minute, OR = 1.013, 95% CI = 1.002-1.024), global PSQI score (OR = 1.134, 95% CI = 1.040-1.236), shortest sleep duration (OR = 5.173, 95% CI = 1.563-17.126), and lowest sleep efficiency (OR = 7.351, 95% CI = 1.943-27.946) were independently associated with faster LTL shortening. CONCLUSIONS: Poor sleep quality, specifically short sleep duration, long sleep latency, and low sleep efficiency were associated with faster longitudinal shortening of LTL.


Assuntos
Encurtamento do Telômero , Telômero , Envelhecimento/genética , Humanos , Leucócitos , Estudos Longitudinais , Sono
15.
J Neurochem ; 119(6): 1262-70, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21988238

RESUMO

We examined the neuroprotective effects of the long-acting third-generation dihydropyridine Ca(2+) antagonists, amlodipine besylate (AB) and amlodipine camsylate (AC), on neuronal cell death induced by oxidative stress. Cell viability and levels of free radicals and intracellular signaling proteins were measured after treating primary cultures of cortical neurons with AB, AC, and/or hydrogen peroxide (H(2) O(2) ) under various conditions. Cell viability was not affected by concentrations of AB or AC up to 5 µM but decreased at higher concentrations. Following H(2) O(2) exposure, the viability of cortical neurons decreased in a concentration-dependent manner; however, treatment with AB or AC up to 5 µM restored the viability of H(2) O(2) -injured cortical neurons. Treatment with H(2) O(2) increased the level of free radicals in cortical neurons, and pre-treatment with AB or AC counteracted this in a dose-dependent manner. Similarly, treatment with AB or AC reduced the declines in p85aPI3K, phosphorylated Akt, phosphorylated GSK-3ß, heat-shock transcription factor-1, and Bcl-2 induced by H(2) O(2) , as well as the increases in cyclooxygenase-2, cytosolic cytochrome c, cleaved caspase 9, and cleaved caspase 3. Our results indicate that AB and AC exert similar neuroprotective effects by reducing oxidative stress, enhancing survival signals, and inhibiting death signals.


Assuntos
Anlodipino/farmacologia , Córtex Cerebral/citologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Análise de Variância , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Peróxido de Hidrogênio/farmacologia , Marcação In Situ das Extremidades Cortadas/métodos , Indóis , Ratos
16.
Mol Neurobiol ; 58(4): 1806-1818, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33404978

RESUMO

Angiotensin II receptor blockers (ARBs) have been shown to exert neuroprotective effects by suppressing inflammatory and apoptotic responses. In the present study, the effects of the ARB telmisartan on the NLRP3 inflammasome induced by oxygen-glucose deprivation (OGD) in neural stem cells (NSCs) were investigated, as well as their possible association with the activation of the PI3K pathway. Cultured NSCs were treated with different concentrations of telmisartan and subjected to various durations of OGD. Cell counting, lactate dehydrogenase, bromodeoxyuridine, and colony-forming unit assays were performed to measure cell viability and proliferation. In addition, the activity of intracellular signaling pathways associated with the PI3K pathway and NLRP3 inflammasome was evaluated. Telmisartan alone did not affect NSCs up to a concentration of 10 µM under normal conditions but showed toxicity at a concentration of 100 µM. Moreover, OGD reduced the viability of NSCs in a time-dependent manner. Nevertheless, treatment with telmisartan increased the viability and proliferation of OGD-injured NSCs. Furthermore, telmisartan promoted the expression of survival-related proteins and mRNA while inhibiting the expression of death-related proteins induced by OGD. In particular, telmisartan attenuated OGD-dependent expression of the NLRP3 inflammasome and its related signaling proteins. These beneficial effects of telmisartan were blocked by a PI3K inhibitor. Together, these results indicate that telmisartan attenuated the activation of the NLRP3 inflammasome by triggering the PI3K pathway, thereby contributing to neuroprotection.


Assuntos
Glucose/deficiência , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células-Tronco Neurais/metabolismo , Oxigênio/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Telmisartan/farmacologia , Anilidas/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Espaço Intracelular/metabolismo , Modelos Biológicos , Células-Tronco Neurais/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , PPAR gama/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
J Stroke ; 23(3): 420-436, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34649386

RESUMO

BACKGROUND AND PURPOSE: Previous studies have revealed the diverse neuroprotective effects of GV1001. In this study, we investigated the effects of GV1001 on focal cerebral ischemia-reperfusion injury (IRI) in rats and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced injury in neural stem cells (NSCs) and cortical neurons. METHODS: Focal cerebral IRI was induced by transient middle cerebral artery occlusion (MCAO). Brain diffusion-weighted imaging (DWI) was performed 2 hours after occlusion, and a total of 37 rats were treated by reperfusion with GV1001 or saline 2 hours after occlusion. Fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging, immunohistochemistry, and neurobehavioral function analyses were performed. Additionally, OGD/R-injured NSCs and cortical neurons were treated with different GV1001 concentrations. Cell viability, proliferation, migration, and oxidative stress were determined by diverse molecular analyses. RESULTS: In the stroke model, GV1001 protected neural cells against IRI. The most effective dose of GV1001 was 60 µM/kg. The infarct volume on FLAIR 48 hours after MCAO compared to lesion volume on DWI showed a significantly smaller ratio in the GV1001-treated group. GV1001-treated rats exhibited better behavioral functions than the saline-treated rats. Treatment with GV1001 increased the viability, proliferation, and migration of the OGD/R-injured NSCs. Free radicals were significantly restored by treatment with GV1001. These neuroprotective effects of GV1001 have also been demonstrated in OGD/R-injured cortical neurons. CONCLUSIONS: The results suggest that GV1001 has neuroprotective effects against IRI in NSCs, cortical neurons, and the rat brain. These effects are mediated through the induction of cellular proliferation, mitochondrial stabilization, and anti-apoptotic, anti-aging, and antioxidant effects.

18.
Sci Rep ; 11(1): 13050, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34158530

RESUMO

Microglial activation is a central player in the pathophysiology of Alzheimer's disease (AD). The soluble fragment of triggering receptor expressed on myeloid cells 2 (sTREM2) can serve as a marker for microglial activation and has been shown to be overexpressed in AD. However, the relationship of sTREM2 with other AD biomarkers has not been extensively studied. We investigated the relationship between cerebrospinal fluid (CSF) sTREM2 and other AD biomarkers and examined the correlation of plasma sTREM2 with CSF sTREM2 in a cohort of individuals with AD and without AD. Participants were consecutively recruited from Asan Medical Center from 2018 to 2020. Subjects were stratified by their amyloid positivity and clinical status. Along with other AD biomarkers, sTREM2 level was measured in the plasma as well as CSF. In 101 patients with either amyloid-positive or negative status, CSF sTREM2 was closely associated with CSF T-tau and P-tau and not with Abeta42. CSF sTREM2 levels were found to be strongly correlated with CSF neurofilament light chain. The comparison of CSF and plasma sTREM2 levels tended to have an inverse correlation. Plasma sTREM2 and P-tau levels were oppositely influenced by age. Our results suggest that neuroinflammation may be closely associated with tau-induced neurodegeneration.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/líquido cefalorraquidiano , Receptores Imunológicos/sangue , Fatores Etários , Idoso , Amiloide/metabolismo , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Estudos de Coortes , Bases de Dados como Assunto , Feminino , Humanos , Masculino , Degeneração Neural/sangue , Fosforilação , Solubilidade , Proteínas tau/líquido cefalorraquidiano
19.
Aging (Albany NY) ; 13(12): 15898-15916, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34148030

RESUMO

We aimed to evaluate the feasibility of multidomain intervention (MI) tailored to the Korean context. In an outcome assessor-blinded, randomized controlled trial, participants without dementia and with one or more modifiable dementia risk factors, aged 60-79 years, were randomly assigned to the facility-based MI (FMI; n=51), the home-based MI (HMI; n=51), or the control group receiving general health advice (n=50). The 24-week intervention comprised vascular risk management, cognitive training, social activity, physical exercise, nutrition guidance, and motivational enhancement. The FMI participants performed all intervention programs at a facility three times a week. The HMI participants performed some programs at a facility once every 1-2 weeks and performed others at home. The primary outcome was feasibility measured through retention, adherence, and at least no differences from the control group in the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). In the FMI and HMI groups, the retention rates were 88.2% and 96.1%, and adherence to the intervention was 94.5% and 96.8%, respectively. The RBANS total scale index score improved significantly in the FMI (5.46 ± 7.50, P = 0.004) and HMI (5.50 ± 8.14, P = 0.004) groups compared to the control group (-0.74 ± 11.51). The FMI and HMI are feasible and there are indicators of efficacy.


Assuntos
Cognição/fisiologia , Dieta , Exercício Físico/fisiologia , Instalações de Saúde , Motivação , Gestão de Riscos , Idoso , Biomarcadores/sangue , Determinação de Ponto Final , Estudos de Viabilidade , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Cooperação do Paciente
20.
J Neurol Sci ; 428: 117565, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34311139

RESUMO

BACKGROUND: Telomeres are repetitive DNA sequences of TTAGGG at the ends of chromosomes. Many studies have shown that telomere shortening is associated with aging-related diseases, such as cardiovascular diseases, hypertension, diabetes, cancer, and various neurodegenerative diseases, including Alzheimer's disease, vascular dementia, Parkinson's disease, and dementia with Lewy bodies. However, changes in telomere length (TL) in patients with frontotemporal dementia (FTD) syndrome are unclear. Accordingly, in this study, we assessed TL in blood samples from patients with FTD syndrome. METHODS: Absolute TL was measured in peripheral blood leukocytes from 53 patients with FTD syndromes (25 with behavioral variant FTD, 19 with semantic variant primary progressive aphasia [PPA], six with nonfluent/agrammatic variant PPA, and three with amyotrophic lateral sclerosis [ALS] plus) and 28 cognitively unimpaired (CU) controls using terminal restriction fragment analysis. RESULTS: TL was significantly longer in the FTD group than in the CU group. All FTD subtypes had significantly longer TL than controls. There were no significant differences in TL among FTD syndromes. No significant correlations were found between TL and demographic factors in the FTD group. CONCLUSIONS: Longer telomeres were associated with FTD syndrome, consistent with a recent report demonstrating that longer telomeres are related to ALS. Therefore, our results may support a shared biology between FTD and ALS. More studies with larger sample sizes are needed.


Assuntos
Doença de Alzheimer , Esclerose Lateral Amiotrófica , Demência Frontotemporal , Demência Frontotemporal/genética , Humanos , Síndrome , Telômero/genética
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