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1.
Molecules ; 29(4)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38398590

RESUMO

Rapid screening of botanical extracts for the discovery of bioactive natural products was performed using a fractionation approach in conjunction with flow-injection high-resolution mass spectrometry for obtaining chemical fingerprints of each fraction, enabling the correlation of the relative abundance of molecular features (representing individual phytochemicals) with the read-outs of bioassays. We applied this strategy for discovering and identifying constituents of Centella asiatica (C. asiatica) that protect against Aß cytotoxicity in vitro. C. asiatica has been associated with improving mental health and cognitive function, with potential use in Alzheimer's disease. Human neuroblastoma MC65 cells were exposed to subfractions of an aqueous extract of C. asiatica to evaluate the protective benefit derived from these subfractions against amyloid ß-cytotoxicity. The % viability score of the cells exposed to each subfraction was used in conjunction with the intensity of the molecular features in two computational models, namely Elastic Net and selectivity ratio, to determine the relationship of the peak intensity of molecular features with % viability. Finally, the correlation of mass spectral features with MC65 protection and their abundance in different sub-fractions were visualized using GNPS molecular networking. Both computational methods unequivocally identified dicaffeoylquinic acids as providing strong protection against Aß-toxicity in MC65 cells, in agreement with the protective effects observed for these compounds in previous preclinical model studies.


Assuntos
Doença de Alzheimer , Centella , Ácido Quínico/análogos & derivados , Triterpenos , Humanos , Peptídeos beta-Amiloides/toxicidade , Doença de Alzheimer/tratamento farmacológico , Extratos Vegetais/farmacologia , Cognição , Centella/química , Triterpenos/análise , Bioensaio , Simulação por Computador
2.
Sci Rep ; 14(1): 2148, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272952

RESUMO

There is great interest in developing clinical biomarker assays that can aid in non-invasive diagnosis and/or monitoring of human diseases, such as cancer, cardiovascular disease, and neurological diseases. Yet little is known about the longitudinal stability of miRNAs in human plasma. Here we assessed the intraindividual longitudinal stability of miRNAs in plasma from healthy human adults, and the impact of common factors (e.g., hemolysis, age) that may confound miRNA data. We collected blood by venipuncture biweekly over a 3-month period from 22 research participants who had fasted overnight, isolated total RNA, then performed miRNA qPCR. Filtering and normalization of the qPCR data revealed amplification of 134 miRNAs, 74 of which had high test-retest reliability and low percentage level drift, meaning they were stable in an individual over the 3-month time period. We also determined that, of nuisance factors, hemolysis and tobacco use have the greatest impact on miRNA levels and variance. These findings support that many miRNAs show intraindividual longitudinal stability in plasma from healthy human adults, including some reported as candidate biomarkers for Alzheimer's disease.


Assuntos
MicroRNAs , Adulto , Humanos , MicroRNAs/genética , Hemólise , Reprodutibilidade dos Testes , Plasma , Biomarcadores
3.
Neurobiol Dis ; 174: 105888, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36209948

RESUMO

Based on previous evidence that the non-steroidal estrogen receptor modulator STX mitigates the effects of neurotoxic Amyloid-ß (Aß) in vitro, we have evaluated its neuroprotective benefits in a mouse model of Alzheimer's disease. Cohorts of 5XFAD mice, which begin to accumulate cerebral Aß at two months of age, were treated with orally-administered STX starting at 6 months of age for two months. After behavioral testing to evaluate cognitive function, biochemical and immunohistochemical assays were used to analyze key markers of mitochondrial function and synaptic integrity. Oral STX treatment attenuated Aß-associated mitochondrial toxicity and synaptic toxicity in the brain, as previously documented in cultured neurons. STX also moderately improved spatial memory in 5XFAD mice. In addition, STX reduced markers for reactive astrocytosis and microgliosis surrounding amyloid plaques, and also unexpectedly reduced overall levels of cerebral Aß in the brain. The neuroprotective effects of STX were more robust in females than in males. These results suggest that STX may have therapeutic potential in Alzheimer's Disease.


Assuntos
Doença de Alzheimer , Síndromes Neurotóxicas , Masculino , Feminino , Animais , Camundongos , Doença de Alzheimer/tratamento farmacológico , Moduladores de Receptor Estrogênico/uso terapêutico , Camundongos Transgênicos , Peptídeos beta-Amiloides , Modelos Animais de Doenças , Placa Amiloide/tratamento farmacológico
4.
Anesth Analg ; 135(5): 1048-1056, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35986676

RESUMO

BACKGROUND: The American Geriatrics Society (AGS) Beers Criteria is an explicit list of potentially inappropriate medications (PIMs) best avoided in adults ≥65 years of age. Cognitively impaired and frail surgical patients often experience poor outcomes after surgery, but the impacts of PIMs on these patients are unclear. Our objective was to assess whether perioperative PIM administration was associated with poor outcomes in geriatric surgical patients. We then evaluated the association between PIM administration and postoperative outcomes in subgroups of patients who were frail or cognitively impaired. METHODS: We performed a retrospective cohort study of patients ≥65 years of age who underwent elective inpatient surgery at a large academic medical center from February 2018 to January 2020. Edmonton Frail Scale and Mini-Cog screening tools were administered to all patients at their preoperative clinic visit. A Mini-Cog score of 0 to 2 was considered cognitive impairment, and frailty was defined by an Edmonton Frail Scale score of ≥8. Patients were divided into 2 groups depending on whether they received at least 1 PIM (PIM+), based on the 2019 AGS Beers Criteria, in the perioperative period or none (PIM-). We assessed the association of preoperative frailty, cognitive impairment, and perioperative PIM administration with the length of hospital stay and discharge disposition using multiple regression analyses adjusted for age, sex, ASA physical status, and intensive care unit (ICU) admission. RESULTS: Of the 1627 included patients (mean age, 73.7 years), 69.3% (n = 1128) received at least 1 PIM. A total of 12.7% of patients were frail, and 11.1% of patients were cognitively impaired; 64% of the frail patients and 58% of the cognitively impaired patients received at least 1 PIM. Perioperative PIM administration was associated with longer hospital stay after surgery (PIM-, 3.56 ± 5.2 vs PIM+, 4.93 ± 5.66 days; P < .001; 95% confidence interval [CI], 0.360-0.546). Frail patients who received PIMs had an average length of stay (LOS) that was nearly 2 days longer than frail patients who did not receive PIMs (PIM-, 4.48 ± 5.04 vs PIM+, 6.33 ± 5.89 days; P = .02). Multiple regression analysis revealed no significant association between PIM administration and proportion of patients discharged to a care facility (PIM+, 26.3% vs PIM-, 28.7%; P = .87; 95% CI, -0.046 to 0.054). CONCLUSIONS: Perioperative PIM administration was common in older surgical patients, including cognitively impaired and frail patients. PIM administration was associated with an increased hospital LOS, particularly in frail patients. There was no association found between PIM administration and discharge disposition.


Assuntos
Fragilidade , Lista de Medicamentos Potencialmente Inapropriados , Humanos , Idoso , Estudos Retrospectivos , Alta do Paciente , Hospitalização
5.
J Alzheimers Dis ; 83(3): 1251-1268, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34420963

RESUMO

BACKGROUND: Geriatric surgical patients are at higher risk of developing postoperative neurocognitive disorders (NCD) than younger patients. The specific mechanisms underlying postoperative NCD remain unknown, but they have been linked to genetic risk factors, such as the presence of APOE4, compared to APOE3, and epigenetic modifications caused by exposure to anesthesia and surgery. OBJECTIVE: To test the hypothesis that compared to E3 mice, E4 mice exhibit a more pronounced postoperative cognitive impairment associated with differential DNA methylation in brain regions linked to learning and memory. METHODS: 16-month-old humanized apolipoprotein-E targeted replacement mice bearing E3 or E4 were subjected to surgery (laparotomy) under general isoflurane anesthesia or sham. Postoperative behavioral testing and genome-wide DNA methylation were performed. RESULTS: Exposure to surgery and anesthesia impaired cognition in aged E3, but not E4 mice, likely due to the already lower cognitive performance of E4 prior to surgery. Cognitive impairment in E3 mice was associated with hypermethylation of specific genes, including genes in the Ephrin pathway implicated in synaptic plasticity and learning in adults and has been linked to Alzheimer's disease. Other genes, such as the Scratch Family Transcriptional Repressor 2, were altered after surgery and anesthesia in both the E3 and E4 mice. CONCLUSION: Our findings suggest that the neurocognitive and behavioral effects of surgery and anesthesia depend on baseline neurocognitive status and are associated with APOE isoform-dependent epigenetic modifications of specific genes and pathways involved in memory and learning.


Assuntos
Apolipoproteína E3/genética , Apolipoproteína E4/genética , Disfunção Cognitiva/genética , Metilação de DNA , Camundongos Transgênicos , Complicações Cognitivas Pós-Operatórias , Doença de Alzheimer/genética , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Humanos , Aprendizagem , Masculino , Camundongos
6.
Front Neurol ; 12: 805135, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35173668

RESUMO

The Lewy Body Dementia Association (LBDA) held a virtual event, the LBDA Biofluid/Tissue Biomarker Symposium, on January 25, 2021, to present advances in biomarkers for Lewy body dementia (LBD), which includes dementia with Lewy bodies (DLBs) and Parkinson's disease dementia (PDD). The meeting featured eight internationally known scientists from Europe and the United States and attracted over 200 scientists and physicians from academic centers, the National Institutes of Health, and the pharmaceutical industry. Methods for confirming and quantifying the presence of Lewy body and Alzheimer's pathology and novel biomarkers were discussed.

7.
Antioxidants (Basel) ; 8(12)2019 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-31817977

RESUMO

Centella asiatica (CA) herb is a traditional medicine, long reputed to provide cognitive benefits. We have reported that CA water extract (CAW) treatment improves cognitive function of aged Alzheimer's disease (AD) model Tg2576 and wild-type (WT) mice, and induces an NRF2-regulated antioxidant response in aged WT mice. Here, CAW was administered to AD model 5XFAD female and male mice and WT littermates (age: 7.6 +/ - 0.6 months), and object recall and contextual fear memory were tested after three weeks treatment. CAW's impact on amyloid-ß plaque burden, and markers of neuronal oxidative stress and synaptic density, was assessed after five weeks treatment. CAW antioxidant activity was evaluated via nuclear transcription factor (erythroid-derived 2)-like 2 (NRF2) and NRF2-regulated antioxidant response element gene expression. Memory improvement in both genders and genotypes was associated with dose-dependent CAW treatment without affecting plaque burden, and marginally increased synaptic density markers in the hippocampus and prefrontal cortex. CAW treatment increased Nrf2 in hippocampus and other NRF2 targets (heme oxygenase-1, NAD(P)H quinone dehydrogenase 1, glutamate-cysteine ligase catalytic subunit). Reduced plaque-associated SOD1, an indicator of oxidative stress, was observed in the hippocampi and cortices of CAW-treated 5XFAD mice. We postulate that CAW treatment leads to reduced oxidative stress, contributing to improved neuronal health and cognition.

8.
J Neurol Sci ; 400: 188-193, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30981123

RESUMO

BACKGROUND/AIMS: Prostate specific antigen (PSA) is regulated by steroid hormones, such as testosterone, the serum levels of which are altered in patients with Alzheimer's disease (AD).This pilot study compared serum levels of the free (f) PSA between AD, mild cognitive impairment (MCI), and control subjects, and evaluated the relationship between fPSA serum levels and cognitive assessment tests and neuroimaging data. In addition, in a subgroup of AD patients, we correlated fPSA serum levels with the existing data on serum levels of amyloid-beta (Aß), and iron-related proteins, including hepcidin and ferritin. METHODS: Frozen serum samples from the Oregon Tissue Bank were used to measure serum levels of fPSA using enzyme-linked immunosorbent assay. RESULTS: fPSA serum levels calculated as median ±â€¯SD were higher in AD males (663.6 ±â€¯821.0 pg/ml) compared to control males (152.0 ±â€¯207.0 pg/ml), p = 0.003. A similar Pattern emerged when comparing MCI males (310.7 ±â€¯367.0 pg/ml) to control males (P = 0.02). Correlation studies showed a significant association between fPSA and CDR (r = 0.56, P = 0.006) and CDR-SOB (r = 0.54, P = 0.009) in AD males. CONCLUSION: Additional studies in a larger cohort are required for determining whether fPSA can be used as biomarker of AD disease progression and whether it has the potential to identify male subjects at risk of AD dementia.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico , Antígeno Prostático Específico/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Biomarcadores/sangue , Disfunção Cognitiva/psicologia , Humanos , Masculino , Pessoa de Meia-Idade
9.
Biol Sex Differ ; 10(1): 14, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30922389

RESUMO

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a common postoperative complication experienced by patients aged 65 years and older, and these older adults comprise more than one third of the surgical patients in the USA. Because not everyone with a history of exposure to surgery and anesthesia develops POCD, there are likely major biological risk factors involved. There are important gaps in our knowledge regarding whether genetic makeup, biological sex, or other Alzheimer's disease risk factors predispose older adults to developing POCD. We set out to determine whether biological sex and Apolipoprotein E-ε4 (APOE4) carrier status increase the risk of developing POCD in older adults. METHODS: We performed a cohort analysis of 1033 participants of prospective longitudinal aging studies. Participants underwent regular cognitive test batteries and we compared the annual rate of change over time in various cognitive measures in the women exposed to surgery and general anesthesia compared to the men exposed to surgery and general anesthesia. Mixed-effects statistical models were used to assess the relationship between biological sex, APOE4 carrier status, surgery and anesthesia exposure, and the rate of change in cognitive test scores. RESULTS: When comparing all men (n = 89) and women (n = 164) who had surgery, there were no significant sex differences in postoperative cognitive outcomes. However, men with an APOE4 allele performed significantly worse on cognitive testing following surgery and anesthesia than women APOE4 carriers, even after adjusting for age, education level, and comorbidities. CONCLUSIONS: Older men with APOE4 allele may be more vulnerable to postoperative cognitive dysfunction than older women with APOE4 allele.


Assuntos
Anestesia Geral/efeitos adversos , Apolipoproteína E4/genética , Complicações Cognitivas Pós-Operatórias/genética , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Complicações Cognitivas Pós-Operatórias/epidemiologia , Caracteres Sexuais
10.
J Clin Lipidol ; 12(5): 1169-1178, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30017468

RESUMO

BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is a rare disorder due to defective sterol 27-hydroxylase causing a lack of chenodeoxycholic acid (CDCA) production and high plasma cholestanol levels. OBJECTIVES: Our objective was to review the diagnosis and treatment results in 43 CTX cases. METHODS: We conducted a careful review of the diagnosis, laboratory values, treatment, and clinical course in 43 CTX cases. RESULTS: The mean age at diagnosis was 32 years; the average follow-up was 8 years. Cases had the following conditions: 53% chronic diarrhea, 74% cognitive impairment, 70% premature cataracts, 77% tendon xanthomas, 81% neurologic disease, and 7% premature cardiovascular disease. The mean serum cholesterol concentration was 190 mg/dL; the mean plasma cholestanol level was 32 mg/L (normal <5.0 mg/L), which decreased to 6.0 mg/L (-81%) with CDCA therapy generally given as 250 mg orally 3 times daily. Of those tested on treatment, 63% achieved cholestanol levels of <5.0 mg/L; 91% had normal liver enzyme levels; none had significant liver problems after dose adjustment. Treatment improved symptoms in 57% at follow-up, but 20% with advanced disease continued to deteriorate. In the United States, CDCA has been approved for gallstone dissolution, but not for CTX despite long-term efficacy and safety data. CONCLUSIONS: Health care providers seeing young patients with tendon xanthomas and relatively normal cholesterol levels, especially those with cataracts and learning problems, should consider the diagnosis of CTX so they can receive treatment. CDCA should receive regulatory approval to facilitate therapy for the prevention of the complications of the disease.


Assuntos
Xantomatose Cerebrotendinosa/diagnóstico , Xantomatose Cerebrotendinosa/terapia , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
11.
Cancer ; 124(12): 2607-2620, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29624648

RESUMO

BACKGROUND: Central nervous system Langerhans cell histiocytosis (CNS-LCH) brain involvement may include mass lesions and/or a neurodegenerative disease (LCH-ND) of unknown etiology. The goal of this study was to define the mechanisms of pathogenesis that drive CNS-LCH. METHODS: Cerebrospinal fluid (CSF) biomarkers including CSF proteins and extracellular BRAFV600E DNA were analyzed in CSF from patients with CNS-LCH lesions compared with patients with brain tumors and other neurodegenerative conditions. Additionally, the presence of BRAFV600E was tested in peripheral mononuclear blood cells (PBMCs) as well as brain biopsies from LCH-ND patients, and the response to BRAF-V600E inhibitor was evaluated in 4 patients with progressive disease. RESULTS: Osteopontin was the only consistently elevated CSF protein in patients with CNS-LCH compared with patients with other brain pathologies. BRAFV600E DNA was detected in CSF of only 2/20 (10%) cases, both with LCH-ND and active lesions outside the CNS. However, BRAFV600E+ PBMCs were detected with significantly higher frequency at all stages of therapy in LCH patients who developed LCH-ND. Brain biopsies of patients with LCH-ND demonstrated diffuse perivascular infiltration by BRAFV600E+ cells with monocyte phenotype (CD14+ CD33+ CD163+ P2RY12- ) and associated osteopontin expression. Three of 4 patients with LCH-ND treated with BRAF-V600E inhibitor experienced significant clinical and radiologic improvement. CONCLUSION: In LCH-ND patients, BRAFV600E+ cells in PBMCs and infiltrating myeloid/monocytic cells in the brain is consistent with LCH-ND as an active demyelinating process arising from a mutated hematopoietic precursor from which LCH lesion CD207+ cells are also derived. Therapy directed against myeloid precursors with activated MAPK signaling may be effective for LCH-ND. Cancer 2018;124:2607-20. © 2018 American Cancer Society.


Assuntos
Neoplasias Encefálicas/diagnóstico , Histiocitose de Células de Langerhans/diagnóstico , Doenças Neurodegenerativas/diagnóstico , Osteopontina/líquido cefalorraquidiano , Proteínas Proto-Oncogênicas B-raf/genética , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Biópsia , Encéfalo/patologia , Neoplasias Encefálicas/líquido cefalorraquidiano , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Células-Tronco Hematopoéticas/patologia , Histiocitose de Células de Langerhans/líquido cefalorraquidiano , Histiocitose de Células de Langerhans/genética , Histiocitose de Células de Langerhans/patologia , Humanos , Lactente , Recém-Nascido , Leucócitos Mononucleares/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Doenças Neurodegenerativas/líquido cefalorraquidiano , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Estudos Retrospectivos , Adulto Jovem
12.
Oxid Med Cell Longev ; 2017: 7023091, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28883904

RESUMO

Centella asiatica has been used for centuries to enhance memory. We have previously shown that a water extract of Centella asiatica (CAW) protects against the deleterious effects of amyloid-ß (Aß) in neuroblastoma cells and attenuates Aß-induced cognitive deficits in mice. Yet, the neuroprotective mechanism of CAW has yet to be thoroughly explored in neurons from these animals. This study investigates the effects of CAW on neuronal metabolism and oxidative stress in isolated Aß-expressing neurons. Hippocampal neurons from amyloid precursor protein overexpressing Tg2576 mice and wild-type (WT) littermates were treated with CAW. In both genotypes, CAW increased the expression of antioxidant response genes which attenuated the Aß-induced elevations in reactive oxygen species (ROS) and lipid peroxidation in Tg2576 neurons. CAW also improved mitochondrial function in both genotypes and increased the expression of electron transport chain enzymes and mitochondrial labeling, suggesting an increase in mitochondrial content. These data show that CAW protects against mitochondrial dysfunction and oxidative stress in Aß-exposed hippocampal neurons which could contribute to the beneficial effects of the extract observed in vivo. Since CAW also improved mitochondrial function in the absence of Aß, these results suggest a broader utility for other conditions where neuronal mitochondrial dysfunction occurs.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Hipocampo/citologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Triterpenos/farmacologia , Animais , Centella , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais , Espécies Reativas de Oxigênio/metabolismo
13.
J Extracell Vesicles ; 6(1): 1317577, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28717417

RESUMO

We examined the extracellular vesicle (EV) and RNA composition of pooled normal cerebrospinal fluid (CSF) samples and CSF from five major neurological disorders: Alzheimer's disease (AD), Parkinson's disease (PD), low-grade glioma (LGG), glioblastoma multiforme (GBM), and subarachnoid haemorrhage (SAH), representing neurodegenerative disease, cancer, and severe acute brain injury. We evaluated: (I) size and quantity of EVs by nanoparticle tracking analysis (NTA) and vesicle flow cytometry (VFC), (II) RNA yield and purity using four RNA isolation kits, (III) replication of RNA yields within and between laboratories, and (IV) composition of total and EV RNAs by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and RNA sequencing (RNASeq). The CSF contained ~106 EVs/µL by NTA and VFC. Brain tumour and SAH CSF contained more EVs and RNA relative to normal, AD, and PD. RT-qPCR and RNASeq identified disease-related populations of microRNAs and messenger RNAs (mRNAs) relative to normal CSF, in both total and EV fractions. This work presents relevant measures selected to inform the design of subsequent replicative CSF studies. The range of neurological diseases highlights variations in total and EV RNA content due to disease or collection site, revealing critical considerations guiding the selection of appropriate approaches and controls for CSF studies.

14.
Aging Dis ; 8(2): 215-227, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28400987

RESUMO

This pilot study examined the status of the master iron regulatory peptide, hepcidin, and peripheral related iron parameters in Alzheimer's disease (AD) and mild cognitive impairment patients, and evaluated the relationship between iron dyshomeostasis and amyloid-beta (Aß), cognitive assessment tests, neuroimaging and clinical data. Frozen serum samples from the Oregon Tissue Bank were used to measure serum levels of hepcidin, ferritin, Aß40, Aß42 using enzyme-linked immunosorbent assay. Serum transferrin levels were determined indirectly as total iron binding capacity, serum iron was measured and the percent saturation of transferrin calculated. The study variables were correlated with the patients' existing cognitive assessment tests, neuroimaging, and clinical data. Hepcidin, and iron-related proteins tended to be higher in AD patients than controls, reaching statistical significance for ferritin, whereas Aß40, Aß42 serum levels tended to be lower. Patients with pure AD had three times higher serum hepcidin levels than controls; gender differences in hepcidin and iron-related proteins were observed. Patient stratification based on clinical dementia rating-sum of boxes revealed significantly higher levels of iron and iron-related proteins in AD patients in the upper 50% as compared to controls, suggesting that iron dyshomeostasis worsens as cognitive impairment increases. Unlike Aß peptides, iron and iron-related proteins showed significant association with cognitive assessment tests, neuroimaging, and clinical data. Hepcidin and iron-related proteins comprise a group of serum biomarkers that relate to AD diagnosis and AD disease progression. Future studies should determine whether strategies targeted to diminishing hepcidin synthesis/secretion and improving iron homeostasis could have a beneficial impact on AD progression.

15.
J Alzheimers Dis ; 51(2): 391-403, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26890746

RESUMO

Because STX is a selective ligand for membrane estrogen receptors, it may be able to confer the beneficial effects of estrogen without eliciting the deleterious side effects associated with activation of the nuclear estrogen receptors. This study evaluates the neuroprotective properties of STX in the context of amyloid-ß (Aß) exposure. MC65 and SH-SY5Y neuroblastoma cell lines, as well as primary hippocampal neurons from wild type (WT) and Tg2576 mice, were used to investigate the ability of STX to attenuate cell death, mitochondrial dysfunction, dendritic simplification, and synaptic loss induced by Aß. STX prevented Aß-induced cell death in both neuroblastoma cell lines; it also normalized the decrease in ATP and mitochondrial gene expression caused by Aß in these cells. Notably, STX also increased ATP content and mitochondrial gene expression in control neuroblastoma cells (in the absence of Aß). Likewise in primary neurons, STX increased ATP levels and mitochondrial gene expression in both genotypes. In addition, STX treatment enhanced dendritic arborization and spine densities in WT neurons and prevented the diminished outgrowth of dendrites caused by Aß exposure in Tg2576 neurons. These data suggest that STX can act as an effective neuroprotective agent in the context of Aß toxicity, improving mitochondrial function as well as dendritic growth and synaptic differentiation. In addition, since STX also improved these endpoints in the absence of Aß, this compound may have broader therapeutic value beyond Alzheimer's disease.


Assuntos
Acrilamidas/farmacologia , Peptídeos beta-Amiloides/toxicidade , Moduladores de Receptor Estrogênico/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Genes Mitocondriais/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Mitocôndrias/fisiologia , Neurônios/patologia , Neurônios/fisiologia
16.
Am J Pathol ; 186(3): 500-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26724389

RESUMO

Three key elements to precision medicine are stratification by risk, detection of pathophysiological processes as early as possible (even before clinical presentation), and alignment of mechanism of action of intervention(s) with an individual's molecular driver(s) of disease. Used for decades in the management of some rare diseases and now gaining broad currency in cancer care, a precision medicine approach is beginning to be adapted to cognitive impairment and dementia. This review focuses on the application of precision medicine to address the clinical and biological complexity of two common neurodegenerative causes of dementia: Alzheimer disease and Parkinson disease.


Assuntos
Demência/fisiopatologia , Doença de Parkinson/fisiopatologia , Medicina de Precisão , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/terapia , Transtornos Cognitivos/genética , Transtornos Cognitivos/fisiopatologia , Demência/genética , Humanos , Mutação , Doença de Parkinson/genética , Doença de Parkinson/terapia
17.
Alzheimers Dement ; 12(5): 590-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26610898

RESUMO

INTRODUCTION: In preclinical studies, surgery/anesthesia contribute to cognitive decline and enhance neuropathologic changes underlying Alzheimer's disease (AD). Nevertheless, the link between surgery, anesthesia, apolipoprotein E ε4 (APOE ε4), and AD remains unclear. METHODS: We performed a retrospective cohort analysis of two prospective longitudinal aging studies. Mixed-effects statistical models were used to assess the relationship between surgical/anesthetic exposure, the APOE genotype, and rate of change in measures of cognition, function, and brain volumes. RESULTS: The surgical group (n = 182) experienced a more rapid rate of deterioration compared with the nonsurgical group (n = 345) in several cognitive, functional, and brain magnetic resonance imaging measures. Furthermore, there was a significant synergistic effect of anesthesia/surgery exposure and presence of the APOE ε4 allele in the decline of multiple cognitive and functional measures. DISCUSSION: These data provide insight into the role of surgical exposure as a risk factor for cognitive and functional decline in older adults.


Assuntos
Atividades Cotidianas , Ventrículos Cerebrais/anormalidades , Transtornos Cognitivos/etiologia , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Transtornos Cognitivos/genética , Progressão da Doença , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco
18.
J Extracell Vesicles ; 4: 27495, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26320940

RESUMO

Ten ongoing studies designed to test the possibility that extracellular RNAs may serve as biomarkers in human disease are described. These studies, funded by the NIH Common Fund Extracellular RNA Communication Program, examine diverse extracellular body fluids, including plasma, serum, urine and cerebrospinal fluid. The disorders studied include hepatic and gastric cancer, cardiovascular disease, chronic kidney disease, neurodegenerative disease, brain tumours, intracranial haemorrhage, multiple sclerosis and placental disorders. Progress to date and the plans for future studies are outlined.

19.
Mol Cell Proteomics ; 14(3): 544-55, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25556233

RESUMO

Finding robust biomarkers for Parkinson disease (PD) is currently hampered by inherent technical limitations associated with imaging or antibody-based protein assays. To circumvent the challenges, we adapted a staged pipeline, starting from our previous proteomic profiling followed by high-throughput targeted mass spectrometry (MS), to identify peptides in human cerebrospinal fluid (CSF) for PD diagnosis and disease severity correlation. In this multicenter study consisting of training and validation sets, a total of 178 subjects were randomly selected from a retrospective cohort, matching age and sex between PD patients, healthy controls, and neurological controls with Alzheimer disease (AD). From ∼14,000 unique peptides displaying differences between PD and healthy control in proteomic investigations, 126 peptides were selected based on relevance and observability in CSF using bioinformatic analysis and MS screening, and then quantified by highly accurate and sensitive selected reaction monitoring (SRM) in the CSF of 30 PD patients versus 30 healthy controls (training set), followed by diagnostic (receiver operating characteristics) and disease severity correlation analyses. The most promising candidates were further tested in an independent cohort of 40 PD patients, 38 AD patients, and 40 healthy controls (validation set). A panel of five peptides (derived from SPP1, LRP1, CSF1R, EPHA4, and TIMP1) was identified to provide an area under curve (AUC) of 0.873 (sensitivity = 76.7%, specificity = 80.0%) for PD versus healthy controls in the training set. The performance was essentially confirmed in the validation set (AUC = 0.853, sensitivity = 82.5%, specificity = 82.5%). Additionally, this panel could also differentiate the PD and AD groups (AUC = 0.990, sensitivity = 95.0%, specificity = 97.4%). Furthermore, a combination of two peptides belonging to proteins TIMP1 and APLP1 significantly correlated with disease severity as determined by the Unified Parkinson's Disease Rating Scale motor scores in both the training (r = 0.381, p = 0.038)j and the validation (r = 0.339, p = 0.032) sets. The novel panel of CSF peptides, if validated in independent cohorts, could be used to assist in clinical diagnosis of PD and has the potential to help monitoring or predicting disease progression.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Espectrometria de Massas/métodos , Doença de Parkinson/líquido cefalorraquidiano , Peptídeos/líquido cefalorraquidiano , Proteômica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Curva ROC , Estudos Retrospectivos
20.
J Alzheimers Dis ; 45(3): 933-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25633675

RESUMO

BACKGROUND: We previously showed that a water extract of the medicinal plant Centella asiatica (CAW) attenuates amyloid-ß (Aß)-induced cognitive deficits in vivo, and prevents Aß-induced cytotoxicity in vitro. Yet the neuroprotective mechanism of CAW is unknown. OBJECTIVE: The goal of this study was to identify biochemical pathways altered by CAW using in vitro models of Aß toxicity. METHODS: The effects of CAW on aberrations in antioxidant response, calcium homeostasis, and mitochondrial function induced by Aß were evaluated in MC65 and SH-SY5Y neuroblastoma cells. RESULTS: CAW decreased intracellular reactive oxygen species and calcium levels elevated in response to Aß, and induced the expression of antioxidant response genes in both cell lines. In SH-SY5Y cells, CAW increased basal and maximal oxygen consumption without altering spare capacity, and attenuated Aß-induced decreases in mitochondrial respiration. CAW also prevented Aß-induced decreases in ATP and induced the expression of mitochondrial genes and proteins in both cell types. Caffeoylquinic acids from CAW were shown to have a similar effect on antioxidant and mitochondrial gene expression in neuroblastoma cells. Primary rat hippocampal neurons treated with CAW also showed an increase in mitochondrial and antioxidant gene expression. CONCLUSIONS: These data suggest an effect of CAW on mitochondrial biogenesis, which in conjunction with activation of antioxidant response genes and normalizing calcium homeostasis, likely contributes to its neuroprotective action against Aß toxicity.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Mitocôndrias/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/toxicidade , Triterpenos/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Centella/química , Embrião de Mamíferos , Hipocampo/citologia , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Neuroblastoma/patologia , Extratos Vegetais , Fatores de Tempo
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