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The human brain vasculature is of great medical importance: its dysfunction causes disability and death1, and the specialized structure it forms-the blood-brain barrier-impedes the treatment of nearly all brain disorders2,3. Yet so far, we have no molecular map of the human brain vasculature. Here we develop vessel isolation and nuclei extraction for sequencing (VINE-seq) to profile the major vascular and perivascular cell types of the human brain through 143,793 single-nucleus transcriptomes from 25 hippocampus and cortex samples of 9 individuals with Alzheimer's disease and 8 individuals with no cognitive impairment. We identify brain-region- and species-enriched genes and pathways. We reveal molecular principles of human arteriovenous organization, recapitulating a gradual endothelial and punctuated mural cell continuum. We discover two subtypes of human pericytes, marked by solute transport and extracellular matrix (ECM) organization; and define perivascular versus meningeal fibroblast specialization. In Alzheimer's disease, we observe selective vulnerability of ECM-maintaining pericytes and gene expression patterns that implicate dysregulated blood flow. With an expanded survey of brain cell types, we find that 30 of the top 45 genes that have been linked to Alzheimer's disease risk by genome-wide association studies (GWASs) are expressed in the human brain vasculature, and we confirm this by immunostaining. Vascular GWAS genes map to endothelial protein transport, adaptive immune and ECM pathways. Many are microglia-specific in mice, suggesting a partial evolutionary transfer of Alzheimer's disease risk. Our work uncovers the molecular basis of the human brain vasculature, which will inform our understanding of overall brain health, disease and therapy.
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Doença de Alzheimer , Encéfalo , Suscetibilidade a Doenças , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Encéfalo/metabolismo , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Estudo de Associação Genômica Ampla , Hipocampo/irrigação sanguínea , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Camundongos , Microglia/metabolismo , Pericitos/metabolismo , TranscriptomaRESUMO
Physical exercise is generally beneficial to all aspects of human and animal health, slowing cognitive ageing and neurodegeneration1. The cognitive benefits of physical exercise are tied to an increased plasticity and reduced inflammation within the hippocampus2-4, yet little is known about the factors and mechanisms that mediate these effects. Here we show that 'runner plasma', collected from voluntarily running mice and infused into sedentary mice, reduces baseline neuroinflammatory gene expression and experimentally induced brain inflammation. Plasma proteomic analysis revealed a concerted increase in complement cascade inhibitors including clusterin (CLU). Intravenously injected CLU binds to brain endothelial cells and reduces neuroinflammatory gene expression in a mouse model of acute brain inflammation and a mouse model of Alzheimer's disease. Patients with cognitive impairment who participated in structured exercise for 6 months had higher plasma levels of CLU. These findings demonstrate the existence of anti-inflammatory exercise factors that are transferrable, target the cerebrovasculature and benefit the brain, and are present in humans who engage in exercise.
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Doença de Alzheimer , Encefalite , Doença de Alzheimer/metabolismo , Animais , Clusterina/genética , Clusterina/metabolismo , Células Endoteliais/metabolismo , Humanos , Camundongos , ProteômicaRESUMO
BACKGROUND: Benign prostatic hyperplasia (BPH) is a condition generally associated with advanced age in men that can be accompanied by bothersome lower urinary tract symptoms (LUTS) including intermittency, weak stream, straining, urgency, frequency, and incomplete bladder voiding. Pharmacotherapies for LUTS/BPH include alpha-blockers, which relax prostatic and urethral smooth muscle and 5É-reductase inhibitors such as finasteride, which can block conversion of testosterone to dihydrotestosterone thereby reducing prostate volume. Celecoxib is a cyclooxygenase-2 inhibitor that reduces inflammation and has shown some promise in reducing prostatic inflammation and alleviating LUTS for some men with histological BPH. However, finasteride and celecoxib can reduce mitochondrial function in some contexts, potentially impacting their efficacy for alleviating BPH-associated LUTS. METHODS: To determine the impact of these pharmacotherapies on mitochondrial function in prostate tissues, we performed immunostaining of mitochondrial Complex I (CI) protein NADH dehydrogenase [ubiquinone] iron-sulfur protein 3 (NDUFS3) and inflammatory cells on BPH specimens from patients naïve to treatment, or who were treated with celecoxib and/or finasteride for 28 days, as well as prostate tissues from male mice treated with celecoxib or vehicle control for 28 days. Quantification and statistical correlation analyses of immunostaining were performed. RESULTS: NDUFS3 immunostaining was decreased in BPH compared to normal adjacent prostate. Patients treated with celecoxib and/or finasteride had significantly decreased NDUFS3 in both BPH and normal tissues, and no change in inflammatory cell infiltration compared to untreated patients. Mice treated with celecoxib also displayed a significant decrease in NDUFS3 immunostaining and no change in inflammatory cell infiltration. CONCLUSIONS: These findings suggest that celecoxib and/or finasteride are associated with an overall decrease in NDUFS3 levels in prostate tissues but do not impact the presence of inflammatory cells, suggesting a decline in mitochondrial CI function in the absence of enhanced inflammation. Given that BPH has recently been associated with increased prostatic mitochondrial dysfunction, celecoxib and/or finasteride may exacerbate existing mitochondrial dysfunction in some BPH patients thereby potentially limiting their overall efficacy in providing metabolic stability and symptom relief.
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BACKGROUND: Despite the misconceptions regarding E-cigarettes (ECs), only a few studies have been conducted in the Middle East that focused on this topic. This study assesses the knowledge of and attitudes towards ECs in Lebanon, determines how these two measures are associated, and identifies the variables that explain each of these measures. METHODS: A cross sectional study was conducted on a convenience sample of Lebanese pedestrians aged between 18 and 64 inclusive. A structured self-administered questionnaire comprising of knowledge and attitude scales, and questions on demographical, health and smoking characteristics was used. RESULTS: Scores for attitudes and knowledge of ECs were summed and dichotomized using a 75% cutoff, above which the participant was considered to have a positive attitude and good knowledge. Among the 352 participants (56.6% males, 43.3% females, mean age 30.3, 46.2% smokers), 63.3% exhibited a lower level of EC knowledge. More than 50% erroneously thought that ECs are not associated with lung and bladder cancer or impair lung and heart function. 65% falsely thought that it is harmless and not addictive. As for attitude, 43.3, 53.9, and 44.3% thought that it is socially acceptable, helps in smoking cessation, and is a good replacement for cigarettes and an enjoyable recreational device respectively. Our results revealed an inverse correlation between attitude and knowledge scores (Spearman's correlation = -.30, p < .001). Predictors of knowledge included health-related occupation (p = .010), regular exercise (p = .016), healthy diet (p = .026), EC use (p = .026), perception that ECs are not harmful (p = .001), and help in smoking cessation (p = .017). Predictors of attitude included EC use (p = .008), sex (p = .010), and knowledge that most ECs are addictive (p = .006), harmful (p = .014), and impair heart and lung function (p = .047). CONCLUSIONS: Our study revealed a gap in EC knowledge, especially among participants who displayed a positive attitude towards ECs. Hence, measures should be undertaken to regulate its use by instituting more stringent laws and holding nationwide awareness campaigns.
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Conhecimentos, Atitudes e Prática em Saúde , Vaping/psicologia , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Líbano , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Inquéritos e Questionários , Vaping/efeitos adversos , Adulto JovemRESUMO
INTRODUCTION: There is a lack of studies on the optimal anti-tumor necrosis factor (anti-TNF) agent for postoperative prophylaxis of Crohn's disease (CD) recurrence. Therefore, we conducted a network meta-analysis (NMA) of prospective trials to compare the efficacy of anti-TNF agents in the prevention of postoperative endoscopic and clinical recurrence of CD following ileocolonic resection. METHODS: We searched PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and recent American gastroenterology association (AGA) meeting abstracts through August 2017. We selected prospective studies comparing anti-TNF agents among each other or to other agents in the setting of postoperative prevention of CD recurrence. We performed a NMA using a frequentist approach with generalized pairwise modeling and inverse variance heterogeneity method. RESULTS: We identified 9 studies, including 571 patients and 5 treatment agents, among which 2 anti-TNF drugs (adalimumab and infliximab). Compared with infliximab, our NMA yielded the following results for endoscopic recurrence: adalimumab [odds ratio (OR), 0.92; 95% confidence interval (CI), 0.18-4.75], thiopurines (OR, 4.11; 95% CI, 0.68-24.78), placebo (OR, 4.39; 95% CI, 0.70-27.68), and Mesalamine (OR, 37.84; 95% CI, 3.77-379.42). For clinical recurrence: adalimumab (OR, 1.03; 95% CI, 0.17-6.03), thiopurines (OR, 1.40; 95% CI, 0.20-10.02), placebo (OR, 1.77; 95% CI, 1.01-3.10), and mesalamine (OR, 16.54; 95% CI, 1.55-176.24). CONCLUSIONS: On the basis of a NMA combining direct and indirect evidence either adalimumab or infliximab may be used in the postoperative prophylaxis of CD recurrence. There is currently a lack of evidence on the use of other anti-TNF agents in this setting.
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Doença de Crohn/cirurgia , Prevenção Secundária/métodos , Inibidores do Fator de Necrose Tumoral/administração & dosagem , Adalimumab/administração & dosagem , Doença de Crohn/prevenção & controle , Humanos , Infliximab/administração & dosagem , Período Pós-Operatório , Recidiva , Fator de Necrose Tumoral alfa/antagonistas & inibidoresRESUMO
BACKGROUND AND PURPOSE: Resveratrol, at least in part via SIRT1 (silent information regulator 2 homologue 1) activation, protects against cerebral ischemia when administered 2 days before injury. However, it remains unclear if SIRT1 activation must occur, and in which brain cell types, for the induction of neuroprotection. We hypothesized that neuronal SIRT1 is essential for resveratrol-induced ischemic tolerance and sought to characterize the metabolic pathways regulated by neuronal Sirt1 at the cellular level in the brain. METHODS: We assessed infarct size and functional outcome after transient 60 minute middle cerebral artery occlusion in control and inducible, neuronal-specific SIRT1 knockout mice. Nontargeted primary metabolomics analysis identified putative SIRT1-regulated pathways in brain. Glycolytic function was evaluated in acute brain slices from adult mice and primary neuronal-enriched cultures under ischemic penumbra-like conditions. RESULTS: Resveratrol-induced neuroprotection from stroke was lost in neuronal Sirt1 knockout mice. Metabolomics analysis revealed alterations in glucose metabolism on deletion of neuronal Sirt1, accompanied by transcriptional changes in glucose metabolism machinery. Furthermore, glycolytic ATP production was impaired in acute brain slices from neuronal Sirt1 knockout mice. Conversely, resveratrol increased glycolytic rate in a SIRT1-dependent manner and under ischemic penumbra-like conditions in vitro. CONCLUSIONS: Our data demonstrate that resveratrol requires neuronal SIRT1 to elicit ischemic tolerance and identify a novel role for SIRT1 in the regulation of glycolytic function in brain. Identification of robust neuroprotective mechanisms that underlie ischemia tolerance and the metabolic adaptations mediated by SIRT1 in brain are crucial for the translation of therapies in cerebral ischemia and other neurological disorders.
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Isquemia Encefálica/metabolismo , Glicólise/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Sirtuína 1/metabolismo , Estilbenos/farmacologia , Acidente Vascular Cerebral/metabolismo , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/genética , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Resveratrol , Sirtuína 1/genética , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/patologiaRESUMO
Astrocytes are a morphologically and functionally heterogeneous population of cells that play critical roles in neurodevelopment and in the regulation of central nervous system homeostasis. Studies of human astrocytes have been hampered by the lack of specific molecular markers and by the difficulties associated with purifying and culturing astrocytes from adult human brains. Human neural progenitor cells (NPCs) with self-renewal and multipotent properties represent an appealing model system to gain insight into the developmental genetics and function of human astrocytes, but a comprehensive molecular characterization that confirms the validity of this cellular system is still missing. Here we used an unbiased transcriptomic analysis to characterize in vitro culture of human NPCs and to define the gene expression programs activated during the differentiation of these cells into astrocytes using FBS or the combination of CNTF and BMP4. Our results demonstrate that in vitro cultures of human NPCs isolated during the gliogenic phase of neurodevelopment mainly consist of radial glial cells (RGCs) and glia-restricted progenitor cells. In these cells the combination of CNTF and BMP4 activates the JAK/STAT and SMAD signaling cascades, leading to the inhibition of oligodendrocytes lineage commitment and activation of astrocytes differentiation. On the other hand, FBS-derived astrocytes have properties of reactive astrocytes. Our work suggests that in vitro culture of human NPCs represents a valuable cellular system to study human disorders characterized by impairment of astrocytes development and function. Our datasets represent an important resource for researchers studying human astrocytes development and might set the basis for the discovery of novel human-specific astrocyte markers.
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Astrócitos/metabolismo , Células-Tronco Embrionárias/metabolismo , Células-Tronco Neurais/metabolismo , Transcriptoma , Astrócitos/citologia , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Células Cultivadas , Fator Neurotrófico Ciliar/genética , Fator Neurotrófico Ciliar/metabolismo , Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Janus Quinases/genética , Janus Quinases/metabolismo , Células-Tronco Neurais/citologia , Neurogênese , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Proteínas Smad/genética , Proteínas Smad/metabolismoRESUMO
BACKGROUND: Alcohol-associated liver disease (ALD) is the most common indication for liver transplantation in the United States. Alcohol use disorder (AUD) treatment is recommended in all patients with ALD and AUD, but it remains underutilized. AIMS: To identify predictors of AUD treatment and to assess 30-day readmission, return to drinking, and 1-year transplant-free survival. METHODS: Retrospective single-center cohort study of consecutive patients hospitalized with ALD and AUD between 2018 and 2020. Patients who died or were lost to follow-up at 90 days after hospitalization were excluded. AUD treatment was defined as receiving medication or participating in residential, outpatient, or support groups within 90 days of discharge. RESULTS: One hundred nine patients were included. Mean age was 51.7 years, and 63% were male. Fifty-six (51%) patients received AUD treatment, and 23 (21%) patients received more than one treatment. Predictors of AUD treatment were younger age (OR, 1.07 [95% CI, 1.04-1.12]; P < 0.001), gastroenterology/hepatology consult (AOR, 8.54 [95% CI, 2.55-39.50]; P = 0.0002), addiction psychiatry consult (AOR, 2.77 [95% CI, 1.16-6.84]; P = 0.02), and a brief AUD intervention (AOR, 18.19 [95% CI, 3.36-339.07]; P = 0.0001). Cirrhosis decompensation, MELD-Na score, and insurance status were not associated with treatment. Thirty-one patients (28.4%) were readmitted, and 29 (26.6%) remained abstinent 30 days from discharge. Patients who received treatment had improved transplant-free survival (HR, 0.44, P = 0.04). CONCLUSION: A brief intervention on AUD had the strongest association with receiving AUD treatment in our cohort. Further efforts to incorporate brief interventions when offering AUD treatment to patients with ALD may be beneficial.
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A major concern for cardiac arrest (CA) survivors is the manifestation of long-term cognitive impairments. Physical exercise (PE) is a well-established approach to improve cognitive functions under certain pathological conditions. We previously showed that PE post-CA mitigates cognitive deficits, but the underlying mechanisms remain unknown. To define neuroprotective mechanisms, we analyzed whether PE post-CA protects neurons involved in memory. We first performed a contextual fear conditioning (CFC) test to confirm that PE post-CA preserves memory in rats. We then conducted a cell-count analysis and determined the number of live cells in the hippocampus, and septal and thalamic nuclei, all areas involved in cognitive functions. Lastly, we performed RNA-seq to determine PE post-CA effect on gene expression. Following CA, exercised rats had preserved CFC memory than sham PE animals. Despite this outcome, PE post-CA did not protect hippocampal cells from dying. However, PE ameliorated cell death in septal and thalamic nuclei compared to sham PE animals, suggesting that these nuclei are crucial in mitigating cognitive decline post-CA. Interestingly, PE affected regulation of genes related to neuroinflammation, plasticity, and cell death. These findings reveal potential mechanisms whereby PE post-CA preserves cognitive functions by protecting septal and thalamic cells via gene regulation.
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Parada Cardíaca , Hipocampo , Ratos , Animais , Hipocampo/metabolismo , Medo/fisiologia , Medo/psicologia , Núcleos Talâmicos , Morte Celular , Parada Cardíaca/patologia , Exercício FísicoRESUMO
Turmeric is a common herbal supplement used for its possible anti-inflammatory and other properties. It is marketed as safe with few reports of major adverse effects directly related to oral supplementation. We report a case of turmeric supplement-induced liver injury in a 49-year-old woman admitted with elevated aspartate aminotransferase and alanine aminotransferase with no history of liver disease or alcohol use disorder. Thus, this case re-emphasizes the importance of evaluating herbal and dietary supplements as potential drug-induced liver injury causes.
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BACKGROUND: Fibrolamellar hepatocellular carcinoma (FL-HCC) is a rare and distinct type of hepatocellular carcinoma that frequently presents in an advanced stage in younger patients with no underlying liver disease. Currently, there is a limited understanding of factors that impact outcomes in FL-HCC. AIM: To characterize the survival of FL-HCC by age, race, and surgical intervention. METHODS: This is a retrospective study of The Surveillance, Epidemiology, and End Results database. We identified patients with FL-HCC between 2000-2018 by using an ICD-O-3 site code C22.0 and a histology code 8171/3: Hepatocellular carcinoma, fibrolamellar. In addition, demographics, tumor characteristics, types of surgical procedure, stages, and survival data were obtained. We conducted three separate survival analyses by age groups; ≤ 19, 20-59, and ≥ 60-year-old, and race; White, Black, Hispanic, Asian and Pacific islanders (API), and surgical types; Wedge resection or segmental resection, lobectomy, extended lobectomy (lobectomy + locoregional therapy or resection of the other lobe), and transplant. The Chi-Square test analyzed categorical variables, and continuous variables were examined using the Mann-Whitney U test. The Kaplan-Meier survival curve was used to compare survival. Multivariate analysis was done with Cox regression analysis. RESULTS: We identified 225 FL-HCC patients with a mean age of 36.9. Overall median survival was 34 (95%CI: 27-41) mo. Patients ≤ 19-years-old had more advanced disease with positive lymph nodes status. However, they received more surgical interventions such as a wedge, segmental resection, lobectomy, extended lobectomy, and transplant. Survival for ≤ 19 was 85 (95%CI: 37-137) mo, age 20-59 was 29 (95%CI: 18-41) mo, and age ≥ 60 years was 12 (95%CI: 7-31) mo (P < 0.001). There were no differences in stage, lymph node status, metastasis status, and surgical treatment among races. The median survival were; Whites had 39 (95%CI: 29-63), Blacks 26 (95%CI: 5-92), Hispanics 31 (95%CI: 11-54), and APIs 28 (95%CI: 5-39) mo (P = 0.28). Of 225 patients, 111 FL-HCC patients had surgical procedures. Median survivals for a wedge or segmental resection was 112 (95%CI: 78-NA), lobectomy was 92 (95%CI: 57-NA), extended lobectomy was 54 (95%CI: 23-NA), and a transplant was 63 (95%CI: 20-NA) mo (P < 0.001). The median survival was better in patients who had surgical treatments regardless of lymph nodes or metastasis status (P < 0.001). CONCLUSION: FL-HCC occurs in a primarily younger population, but survival can be prolonged despite the aggressive disease. There were no racial differences in the survival of FL-HCC; however, Asians with FL-HCC tended to be older than in other races. Surgical treatment provided better survival even in those patients with nodal disease or metastases. Although future studies are needed to explore other therapies for FL-HCC, surgical options should be considered in all cases of FL-HCC unless contraindicated.
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BACKGROUND: Genetic mutations underlying familial Alzheimer's disease (AD) were identified decades ago, but the field is still in search of transformative therapies for patients. While mouse models based on overexpression of mutated transgenes have yielded key insights in mechanisms of disease, those models are subject to artifacts, including random genetic integration of the transgene, ectopic expression and non-physiological protein levels. The genetic engineering of novel mouse models using knock-in approaches addresses some of those limitations. With mounting evidence of the role played by microglia in AD, high-dimensional approaches to phenotype microglia in those models are critical to refine our understanding of the immune response in the brain. METHODS: We engineered a novel App knock-in mouse model (AppSAA) using homologous recombination to introduce three disease-causing coding mutations (Swedish, Arctic and Austrian) to the mouse App gene. Amyloid-ß pathology, neurodegeneration, glial responses, brain metabolism and behavioral phenotypes were characterized in heterozygous and homozygous AppSAA mice at different ages in brain and/ or biofluids. Wild type littermate mice were used as experimental controls. We used in situ imaging technologies to define the whole-brain distribution of amyloid plaques and compare it to other AD mouse models and human brain pathology. To further explore the microglial response to AD relevant pathology, we isolated microglia with fibrillar Aß content from the brain and performed transcriptomics and metabolomics analyses and in vivo brain imaging to measure energy metabolism and microglial response. Finally, we also characterized the mice in various behavioral assays. RESULTS: Leveraging multi-omics approaches, we discovered profound alteration of diverse lipids and metabolites as well as an exacerbated disease-associated transcriptomic response in microglia with high intracellular Aß content. The AppSAA knock-in mouse model recapitulates key pathological features of AD such as a progressive accumulation of parenchymal amyloid plaques and vascular amyloid deposits, altered astroglial and microglial responses and elevation of CSF markers of neurodegeneration. Those observations were associated with increased TSPO and FDG-PET brain signals and a hyperactivity phenotype as the animals aged. DISCUSSION: Our findings demonstrate that fibrillar Aß in microglia is associated with lipid dyshomeostasis consistent with lysosomal dysfunction and foam cell phenotypes as well as profound immuno-metabolic perturbations, opening new avenues to further investigate metabolic pathways at play in microglia responding to AD-relevant pathogenesis. The in-depth characterization of pathological hallmarks of AD in this novel and open-access mouse model should serve as a resource for the scientific community to investigate disease-relevant biology.
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Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Amiloidose/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Microglia/metabolismo , Placa Amiloide/patologia , Receptores de GABA/metabolismoRESUMO
Brain-derived neurotrophic factor (Bdnf) expression is tightly controlled at the transcriptional and post-transcriptional levels. Previously, we showed that inhibition of noncoding Bdnf antisense (Bdnf-AS) RNA upregulates Bdnf protein. Here, we generated a Bdnf-antisense knockout (Bdnf-AS KO) mouse model by deleting 6 kilobases upstream of Bdnf-AS. After verifying suppression of Bdnf-AS, baseline behavioral tests indicated no significant difference in knockout and wild type mice, except for enhanced cognitive function in the knockout mice in the Y-maze. Following acute involuntary exercise, Bdnf-AS KO mice were re-assessed and a significant increase in Bdnf mRNA and protein were observed. Following long-term involuntary exercise, we observed a significant increase in nonspatial and spatial memory in novel object recognition and Barnes maze tests in young and aged Bdnf-AS KO mice. Our data provides evidence for the beneficial effects of endogenous Bdnf upregulation and the synergistic effect of Bdnf-AS knockout on exercise and memory retention.
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The preservation of mitochondrial function is a major protective strategy for cerebral ischemic injuries. Previously, our laboratory demonstrated that protein kinase C epsilon (PKCε) promotes the synthesis of mitochondrial nicotinamide adenine dinucleotide (NAD+). NAD+ along with its reducing equivalent, NADH, is an essential co-factor needed for energy production from glycolysis and oxidative phosphorylation. Yet, NAD+/NADH are impermeable to the inner mitochondrial membrane and their import into the mitochondria requires the activity of specific shuttles. The most important neuronal NAD+/NADH shuttle is the malate-aspartate shuttle (MAS). The MAS has been implicated in synaptic function and is potentially dysregulated during cerebral ischemia. The aim of this study was to determine if metabolic changes induced by PKCε preconditioning involved regulation of the MAS. Using primary neuronal cultures, we observed that the activation of PKCε enhanced mitochondrial respiration and glycolysis in vitro. Conversely, inhibition of the MAS resulted in decreased oxidative phosphorylation and glycolytic capacity. We further demonstrated that activation of PKCε increased the phosphorylation of key components of the MAS in rat brain synaptosomal fractions. Additionally, PKCε increased the enzyme activity of glutamic oxaloacetic transaminase 2 (GOT2), an effect that was dependent on the import of PKCε into the mitochondria and phosphorylation of GOT2. Furthermore, PKCε activation was able to rescue decreased GOT2 activity induced by ischemia. These findings reveal novel protective targets and mechanisms against ischemic injury, which involves PKCε-mediated phosphorylation and activation of GOT2 in the MAS.
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Aspartato Aminotransferase Mitocondrial/metabolismo , Isquemia Encefálica/enzimologia , NAD/metabolismo , Neurônios/enzimologia , Proteína Quinase C-épsilon/metabolismo , Animais , Malatos/metabolismo , Masculino , Fosforilação , Cultura Primária de Células , Ratos Sprague-DawleyRESUMO
BACKGROUND: The Breastfeeding Behavior Questionnaire (BBQ) assesses women's perceptions of their breastfeeding behavior. It was adapted to several languages and used in different settings, but has not been validated in Arabic-speaking populations. None of the previous studies that used the BBQ in other cultures examined its ability to predict the actual breastfeeding behaviors of mothers postpartum. This study validated the BBQ in a cohort of Lebanese pregnant women between December 2013 and January 2016, and examined whether it can predict exclusive breastfeeding at one, three and six months. METHODS: The internal consistency reliability and construct validity of the Arabic BBQ (BBQ-A) were tested on 354 pregnant women. Its predictive ability was assessed by correlating the women's BBQ-A scores with their breastfeeding outcomes at one, three and six months post-delivery. RESULTS: The BBQ-A had a good internal consistency reliability (Cronbach's alpha = 0.78). Exploratory factor analysis revealed that it is unidimensional. Inter-item correlations ranged between - 0.016 and 0.934, with corrected-item total correlations ranging from 0.273 to 0.678. Perceived positive breastfeeding behavior correlated with positive breastfeeding attitudes, good breastfeeding knowledge and stronger breastfeeding intention supporting its external validity. However, in binomial multivariate logistic regression analysis, the BBQ-A did not predict exclusive breastfeeding at one, three or six months. CONCLUSIONS: The BBQ-A is a reliable and valid instrument to assess women's perceptions of their breastfeeding behavior in an Arab context. Availability of this instrument is important for investigators conducting breastfeeding research in the Arab world. However, the BBQ-A does not predict exclusive breastfeeding at one, three or six months. Further research on the Breastfeeding Behavior Questionnaire is needed to examine its predictive validity in other cultures.
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Aleitamento Materno/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários/normas , Adulto , Árabes , Ensaios Clínicos como Assunto , Comportamento Alimentar , Feminino , Humanos , Líbano , Gravidez , Psicometria , Reprodutibilidade dos Testes , Adulto JovemRESUMO
Despite its heterogeneity, autism is characterized by a defined behavioral phenotype, suggesting that the molecular pathology affects specific neural substrates to cause behavioral dysfunction. Previous studies identified genes dysregulated in autism cortex but did not address their cell-type specificity. Moreover, it is unknown whether there is a core of genes dysregulated across multiple neocortical regions. We applied RNA sequencing to postmortem brain tissue samples from autism patients and neurologically normal controls and combined our data with previously published datasets. We then identified genes, pathways, and alternative splicing events which are dysregulated in five neocortical regions in autism. To gain information about cell-type specificity of the dysregulated genes, we analyzed single-nuclei RNA sequencing data of adult human cortex and intersected cell-type-specific gene signatures with genes dysregulated in autism in specific cortical regions. We found that autism-associated gene expression changes across 4 frontal and temporal cortex regions converge on 27 genes related to immune response and enriched in human astrocytes, microglia, and brain endothelium. Shared splicing changes, however, are found in genes predominantly associated with synaptic function and adult interneurons and projection neurons. Finally, we demonstrate that regions of DNA differentially methylated in autism overlap genes associated with development and enriched in human cortical oligodendrocytes. Our study identifies signatures of autism molecular pathology shared across neocortical regions, as well as neural cell types enriched for common dysregulated genes, thus paving way for assessing cell-type-specific mechanisms of autism pathology.
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Transtorno do Espectro Autista/genética , Neocórtex/metabolismo , RNA Mensageiro/análise , Processamento Alternativo , Transtorno do Espectro Autista/patologia , Metilação de DNA , Regulação da Expressão Gênica , Ontologia Genética , Humanos , Imunidade/genética , Redes e Vias Metabólicas/genética , Neocórtex/patologia , Neuroglia/metabolismo , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Análise de Célula Única , Sinapses/metabolismo , Lobo Temporal/metabolismo , Lobo Temporal/patologia , TranscriptomaRESUMO
Musculoskeletal disorders remain a major problem in hemodialysis patients. The aim of the study was to estimate the prevalence of musculoskeletal manifestations in hemodialysis patients and identify disease cluster profiles. We performed a cross-sectional study including all adult patients in the hemodialysis unit at Hotel-Dieu de France Hospital. We collected demographic characteristics, musculoskeletal symptoms, biologic parameters, and treatments. Musculoskeletal disorders were classified by a rheumatologist into predefined diagnostic categories. Prevalence was presented, and a cluster analysis was performed. Eighty-nine patients were included, mean age was 67.5 ± 12 years, and 43.8% were female. Dialysis vintage was 5.7 ± 5.37 years. Musculoskeletal symptoms were reported by 76.4% of the patients. Pain was the most frequent symptom (44.9%). The main diagnoses were osteoarthritis (53.9%) and fracture (27%). Musculoskeletal symptoms and disorders were significantly associated with dialysis vintage and age. Cluster analysis identified three patient profiles: younger with low calcium levels, younger but long dialysis vintage with osteoarthritis and carpal tunnel syndrome, and older with long dialysis vintage and fractures. The prevalence of musculoskeletal manifestations is high in the hemodialysis population and increases with dialysis vintage. Musculoskeletal disorders cluster according to age and dialysis vintage. Key Points⢠Musculoskeletal symptoms are highly prevalent among hemodialysis patients (76.4%).⢠All musculoskeletal disorders are associated with dialysis vintage and age.⢠Three clusters are identified among hemodialysis patients: young with low calcium levels, young but long dialysis vintage with osteoarthritis and carpal tunnel syndrome and old with long dialysis vintage with fractures.
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Síndrome do Túnel Carpal/epidemiologia , Fraturas Ósseas/epidemiologia , Falência Renal Crônica/terapia , Dor Musculoesquelética/epidemiologia , Osteoartrite/epidemiologia , Diálise Renal/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Cálcio/sangue , Condrocalcinose/epidemiologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/sangue , Distúrbio Mineral e Ósseo na Doença Renal Crônica/epidemiologia , Análise por Conglomerados , Duração da Terapia , Feminino , Humanos , Falência Renal Crônica/epidemiologia , Líbano/epidemiologia , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fósforo/sangue , Prevalência , Albumina Sérica/metabolismo , Tendinopatia , Fatores de TempoRESUMO
Neuroprotective agents administered post-cerebral ischemia have failed so far in the clinic to promote significant recovery. Thus, numerous efforts were redirected toward prophylactic approaches such as preconditioning as an alternative therapeutic strategy. Our laboratory has revealed a novel long-term window of cerebral ischemic tolerance mediated by resveratrol preconditioning (RPC) that lasts for 2 weeks in mice. To identify its mediators, we conducted an RNA-seq experiment on the cortex of mice 2 weeks post-RPC, which revealed 136 differentially expressed genes. The majority of genes (116/136) were downregulated upon RPC and clustered into biological processes involved in transcription, synaptic signaling, and neurotransmission. The downregulation in these processes was reminiscent of metabolic depression, an adaptation used by hibernating animals to survive severe ischemic states by downregulating energy-consuming pathways. Thus, to assess metabolism, we used a neuronal-astrocytic co-culture model and measured the cellular respiration rate at the long-term window post-RPC. Remarkably, we observed an increase in glycolysis and mitochondrial respiration efficiency upon RPC. We also observed an increase in the expression of genes involved in pyruvate uptake, TCA cycle, and oxidative phosphorylation, all of which indicated an increased reliance on energy-producing pathways. We then revealed that these nuclear and mitochondrial adaptations, which reduce the reliance on energy-consuming pathways and increase the reliance on energy-producing pathways, are epigenetically coupled through acetyl-CoA metabolism and ultimately increase baseline ATP levels. This increase in ATP would then allow the brain, a highly metabolic organ, to endure prolonged durations of energy deprivation encountered during cerebral ischemia.
Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Isquemia Encefálica/genética , Isquemia Encefálica/fisiopatologia , Metabolismo Energético , Genoma , Precondicionamento Isquêmico , Resveratrol/farmacologia , Acetilcoenzima A/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Isquemia Encefálica/patologia , Respiração Celular/efeitos dos fármacos , Técnicas de Cocultura , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Metabolismo Energético/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Biológicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos Sprague-Dawley , Fatores de Tempo , Transcriptoma/genéticaRESUMO
Sirtuins are evolutionarily conserved proteins that use nicotinamide adenine dinucleotide (NAD+) as a co-substrate in their enzymatic reactions. There are seven proteins (SIRT1-7) in the human sirtuin family, among which SIRT1 is the most conserved and characterized. SIRT1 in the brain, in particular, within the hypothalamus, plays crucial roles in regulating systemic energy homeostasis and circadian rhythm. Apart from this, SIRT1 has also been found to mediate beneficial effects in neurological diseases. In this review, we will first summarize how SIRT1 in the brain relates to obesity, type 2 diabetes, and circadian synchronization, and then we discuss the neuroprotective roles of brain SIRT1 in the context of cerebral ischemia and neurodegenerative disorders.