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1.
JHEP Rep ; 6(4): 101017, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38544553

RESUMEN

Background & Aims: Effective treatments for acute-on-chronic liver failure (ACLF) are a major unmet need. This proof-of-concept pilot study was aimed at evaluating the effects of plasma exchange (PE) with albumin 5% (PE-A5%) on albumin functional capacity and organ dysfunction in patients with ACLF. Methods: Ten adult patients were enrolled in a single-center phase II, prospective, open-label, non-controlled study. Six PE-A5% sessions were performed in 10 days followed by a 1-month follow-up visit. Albumin functional capacity and circulatory function were assessed, as were renal, cerebral, and liver function, and systemic inflammation. The main safety variable was the percentage of PE sessions associated with at least one procedure-related adverse event (AE). Results: Patients with ACLF showed lower albumin binding capacity, lower antioxidant capacity, and lower levels of albumin with preserved structure compared to healthy donors (n = 19). From baseline to day 11, PE-A5% treatment increased albumin levels and improved albumin binding capacity to Sudlow site II (15.3±1.6 mg/ml to 18.9±1.7 mg/ml; p = 0.003), fatty acid-binding capacity (8.2±1.4 µM to 3.1±1.5 µM; p = 0.013) and antioxidant capacity (human mercaptalbumin 9.5±1.5 mg/ml to 14.6±1.6 mg/ml; p = 0.001). Native albumin levels were increased throughout day 1-11 PE-A5% sessions (6.5±1.0 mg/ml to 10.2±1.4 mg/ml; p = 0.035). PE-A5% improved systemic hemodynamics (mean arterial pressure, heart rate, cardiac index), renal function (creatinine level, blood urea nitrogen), cerebral function (hepatic encephalopathy grade), liver parameters (transaminases, bilirubin) and inflammatory parameters (C-reactive protein, leukocyte count). All patients had at least one of the 78 AEs reported, mostly mild (product/procedure-related: 36%). Sixteen serious AEs were reported in eight patients (procedure/product-related: none). Conclusions: PE-A5% was a safe procedure associated with positive effects on albumin functionality, and circulatory, renal, cerebral, and liver function in patients with ACLF. Impact and implications: Acute-on-chronic liver failure (ACLF) is a clinical condition characterized by severe systemic inflammation, organ failure, and high mortality. Plasma exchange removes patient's plasma containing pathogenic substances, replacing it with 5% albumin and fresh frozen plasma (PE-A5%). In this study, cirrhotic patients with ACLF were treated with PE-A5%, which was a safe procedure that increased binding and antioxidant capacity of patients' albumin, while improving circulatory, kidney, brain, and liver functions. These beneficial effects could impact survival in ACLF. ClinicalTrialsgov Identifier: NCT01201720. EudraCT number: 2010-021360-15.

2.
Commun Biol ; 6(1): 1267, 2023 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097664

RESUMEN

Lysine-specific demethylase 1A (LSD1) binds to the REST corepressor (RCOR) protein family of corepressors to erase transcriptionally active marks on histones. Functional diversity in these complexes depends on the type of RCOR included, which modulates the catalytic activity of the complex. Here, we studied the duplicative history of the RCOR and LSD gene families and analyzed the evolution of their interaction. We found that RCOR genes are the product of the two rounds of whole-genome duplications that occurred early in vertebrate evolution. In contrast, the origin of the LSD genes traces back before to the divergence of animals and plants. Using bioinformatics tools, we show that the RCOR and LSD1 interaction precedes the RCOR repertoire expansion that occurred in the last common ancestor of jawed vertebrates. Overall, we trace LSD1-RCOR complex evolution and propose that animal non-model species offer advantages in addressing questions about the molecular biology of this epigenetic complex.


Asunto(s)
Histona Demetilasas , Lisina , Animales , Histona Demetilasas/genética , Histona Demetilasas/metabolismo , Histonas/metabolismo , Vertebrados/genética , Proteínas Co-Represoras/genética , Proteínas Co-Represoras/metabolismo
3.
Int J Mol Sci ; 24(14)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37511412

RESUMEN

Small RNAs (sRNAs) are bioactive molecules that can be detected in biofluids, reflecting physiological and pathological states. In plasma, sRNAs are found within extracellular vesicles (EVs) and in extravesicular compartments, offering potential sources of highly sensitive biomarkers. Deep sequencing strategies to profile sRNAs favor the detection of microRNAs (miRNAs), the best-known class of sRNAs. Phospho-RNA-seq, through the enzymatic treatment of sRNAs with T4 polynucleotide kinase (T4-PNK), has been recently developed to increase the detection of thousands of previously inaccessible RNAs. In this study, we investigated the value of phospho-RNA-seq on both the EVs and extravesicular plasma subfractions. Phospho-RNA-seq increased the proportion of sRNAs used for alignment and highlighted the diversity of the sRNA transcriptome. Unsupervised clustering analysis using sRNA counts matrices correctly classified the EVs and extravesicular samples only in the T4-PNK treated samples, indicating that phospho-RNA-seq stresses the features of sRNAs in each plasma subfraction. Furthermore, T4-PNK treatment emphasized specific miRNA variants differing in the 5'-end (5'-isomiRs) and certain types of tRNA fragments in each plasma fraction. Phospho-RNA-seq increased the number of tissue-specific messenger RNA (mRNA) fragments in the EVs compared with the extravesicular fraction, suggesting that phospho-RNA-seq favors the discovery of tissue-specific sRNAs in EVs. Overall, the present data emphasizes the value of phospho-RNA-seq in uncovering RNA-based biomarkers in EVs.


Asunto(s)
Vesículas Extracelulares , MicroARNs , ARN Pequeño no Traducido , RNA-Seq , Análisis de Secuencia de ARN , MicroARNs/genética , Vesículas Extracelulares/genética , Biomarcadores , ARN Pequeño no Traducido/genética
4.
PLoS One ; 18(4): e0284357, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37053190

RESUMEN

Prenatal ethanol exposure is associated with neurodevelopmental defects and long-lasting cognitive deficits, which are grouped as fetal alcohol spectrum disorders (FASD). The molecular mechanisms underlying FASD are incompletely characterized. Alternative splicing, including the insertion of microexons (exons of less than 30 nucleotides in length), is highly prevalent in the nervous system. However, whether ethanol exposure can have acute or chronic deleterious effects in this process is poorly understood. In this work, we used the bioinformatic tools VAST-TOOLS, rMATS, MAJIQ, and MicroExonator to predict alternative splicing events affected by ethanol from available RNA sequencing data. Experimental protocols of ethanol exposure included human cortical tissue development, human embryoid body differentiation, and mouse development. We found common genes with predicted differential alternative splicing using distinct bioinformatic tools in different experimental designs. Notably, Gene Ontology and KEGG analysis revealed that the alternative splicing of genes related to RNA processing and protein synthesis was commonly affected in the different ethanol exposure schemes. In addition, the inclusion of microexons was also affected by ethanol. This bioinformatic analysis provides a reliable list of candidate genes whose splicing is affected by ethanol during nervous system development. Furthermore, our results suggest that ethanol particularly modifies the alternative splicing of genes related to post-transcriptional regulation, which probably affects neuronal proteome complexity and brain function.


Asunto(s)
Etanol , Trastornos del Espectro Alcohólico Fetal , Embarazo , Femenino , Ratones , Humanos , Animales , Etanol/toxicidad , ARN , Empalme Alternativo , Trastornos del Espectro Alcohólico Fetal/genética , Biología Computacional
5.
FASEB J ; 37(3): e22817, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36809676

RESUMEN

Cytokine-induced inflammation and mitochondrial oxidative stress are key drivers of liver tissue injury. Here, we describe experiments modeling hepatic inflammatory conditions in which plasma leakage leads to large amounts of albumin to reach the interstitium and parenchymal surfaces to explore whether this protein plays a role in preserving hepatocyte mitochondria against the damaging actions of the cytotoxic cytokine tumor necrosis factor alpha (TNFα). Hepatocytes and precision-cut liver slices were cultured in the absence or presence of albumin in the cell media and then exposed to mitochondrial injury with the cytokine TNFα. The homeostatic role of albumin was also investigated in a mouse model of TNFα-mediated liver injury induced by lipopolysaccharide and D-galactosamine (LPS/D-gal). Mitochondrial ultrastructure, oxygen consumption, ATP and reactive oxygen species (ROS) generation, fatty acid ß-oxidation (FAO), and metabolic fluxes were assessed by transmission electron microscopy (TEM), high-resolution respirometry, luminescence-fluorimetric-colorimetric assays and NADH/FADH2 production from various substrates, respectively. TEM analysis revealed that in the absence of albumin, hepatocytes were more susceptible to the damaging actions of TNFα and showed more round-shaped mitochondria with less intact cristae than hepatocytes cultured with albumin. In the presence of albumin in the cell media, hepatocytes also showed reduced mitochondrial ROS generation and FAO. The mitochondria protective actions of albumin against TNFα damage were associated with the restoration of a breakpoint between isocitrate and α-ketoglutarate in the tricarboxylic acid cycle and the upregulation of the antioxidant activating transcription factor 3 (ATF3). The involvement of ATF3 and its downstream targets was confirmed in vivo in mice with LPS/D-gal-induced liver injury, which showed increased hepatic glutathione levels, indicating a reduction in oxidative stress after albumin administration. These findings reveal that the albumin molecule is required for the effective protection of liver cells from mitochondrial oxidative stress induced by TNFα. These findings emphasize the importance of maintaining the albumin levels in the interstitial fluid within the normal range to protect the tissues against inflammatory injury in patients with recurrent hypoalbuminemia.


Asunto(s)
Albúminas , Hepatopatías , Factor de Necrosis Tumoral alfa , Animales , Ratones , Albúminas/metabolismo , Apoptosis , Citocinas/metabolismo , Hepatocitos/metabolismo , Lipopolisacáridos , Hígado/metabolismo , Hepatopatías/metabolismo , Mitocondrias/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/farmacología
6.
Haemophilia ; 28(5): 737-744, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35654086

RESUMEN

INTRODUCTION: Presence of von Willebrand factor (VWF) in FVIII concentrates offers protection against neutralizing inhibitors in haemophilia A (HA). Whether this protection is more evident in plasma-derived (pd) FVIII/VWF or recombinant (r) FVIII concentrates remains controversial. AIM: We investigated the protection exerted by VWF against FVIII inhibitors in an in vivo mouse model of HA exposed to pdFVIII/VWF or to various rFVIII concentrates. METHODS: Haemophilia A mice received the different FVIII concentrates after administration of vehicle or an inhibitory IgG purified from a commercial pool of HA plasma with inhibitors and FVIII:C recoveries were measured. Furthermore, using a novel clinically oriented ex vivo approach, Bethesda inhibitory activities (BU) of a commercial pool of HA plasma with inhibitors were assessed using normal plasma, or plasma from severe HA patients, without inhibitors, after treatment with the same concentrates. RESULTS: in vivo studies showed that pdFVIII/VWF offers markedly higher protection against inhibitors when compared with any of the FVIII products without VWF. More importantly, in the ex vivo studies, plasma from patients treated with pdFVIII/VWF showed higher protection against inhibitors (P values ranging .05-.001) in comparison with that observed in plasma from patients who received FVIII products without VWF, regardless of the type of product evaluated. CONCLUSION: Data indicate that FVIII+VWF complexes assembled in the circulation after rFVIII infusion are not equivalent to the naturally formed complex in pdFVIII/VWF. Therefore, rFVIII infused into HA patients with inhibitors would be less protected by VWF than the FVIII in pdFVIII/VWF concentrates.


Asunto(s)
Factor VIII , Hemofilia A , Factor de von Willebrand , Animales , Modelos Animales de Enfermedad , Factor VIII/administración & dosificación , Factor VIII/inmunología , Factor VIII/aislamiento & purificación , Hemofilia A/terapia , Inmunoglobulina G/inmunología , Ratones , Proteínas Recombinantes/administración & dosificación , Factor de von Willebrand/administración & dosificación , Factor de von Willebrand/aislamiento & purificación
7.
Nat Commun ; 13(1): 1550, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35322029

RESUMEN

RCOR1 is a known transcription repressor that recruits and positions LSD1 and HDAC1/2 on chromatin to erase histone methylation and acetylation. However, there is currently an incomplete understanding of RCOR1's range of localization and function. Here, we probe RCOR1's distribution on a genome-wide scale and unexpectedly find that RCOR1 is predominantly associated with transcriptionally active genes. Biochemical analysis reveals that RCOR1 associates with RNA Polymerase II (POL-II) during transcription and deacetylates its carboxy-terminal domain (CTD) at lysine 7. We provide evidence that this non-canonical RCOR1 activity is linked to dampening of POL-II productive elongation at actively transcribing genes. Thus, RCOR1 represses transcription in two ways-first, via a canonical mechanism by erasing transcriptionally permissive histone modifications through associating with HDACs and, second, via a non-canonical mechanism that deacetylates RNA POL-II's CTD to inhibit productive elongation. We conclude that RCOR1 is a transcription rheostat.


Asunto(s)
Cromatina , ARN Polimerasa II , Acetilación , Cromatina/genética , Metilación , Procesamiento Proteico-Postraduccional , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , Transcripción Genética
8.
Neurol Sci ; 43(5): 3211-3221, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34791571

RESUMEN

BACKGROUND: Plasma exchange (PE) is used to treat a range of neurological disorders. Based on results demonstrated in Alzheimer's disease, we theorized that PE with albumin replacement (PE-A) might alter the metabolic profile of plasma and cerebrospinal fluid in patients with amyotrophic lateral sclerosis (ALS) by removing disease-inducing molecules. The aim of this study was to evaluate the effect of PE-A on disease progression in ALS. METHODS: In this open-label, non-controlled, single-arm, prospective pilot study, 13 adults with ALS had 6 months' treatment with PE-A 5% and 6 months' follow-up. Primary endpoints were changes from baseline in the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) score and forced vital capacity (FVC) through 48 weeks. A post hoc analysis compared individual patient data with the expected ALSFRS-R progression slope. RESULTS: The median ALSFRS-R score declined throughout the study, although the rate of decline was slower than expected in seven patients at treatment end and in five patients at study end. Six patients remained in the same baseline slope progression category, and four patients improved their slope category at treatment end. Median FVC decreased significantly during the study. Treatment was well tolerated. Of 330 PE-A procedures, 0.9% were associated with potentially related adverse events. CONCLUSION: Although functional impairment progressed, about two-thirds of patients showed a slower than expected rate of decline at treatment end. Most patients had unaltered (54.5%) or reduced (36.4%) ALSFRS-R slope progression at treatment end. Further evaluation of PE-A in controlled studies involving more patients is warranted. EUDRACT NUMBER: 2013-004842-40. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02479802.


Asunto(s)
Esclerosis Amiotrófica Lateral , Adulto , Albúminas , Progresión de la Enfermedad , Humanos , Proyectos Piloto , Intercambio Plasmático , Estudios Prospectivos
9.
Artículo en Inglés | MEDLINE | ID: mdl-34501901

RESUMEN

Greenspace is widely related to mental health benefits, but this relationship may vary by social group. Gentrification, as linked to processes of unequal urban development and conflict, potentially impacts health outcomes. This study explores the relationships between greenspace and mental health and between gentrification and mental health associations. It also further examines gentrification as an effect modifier in the greenspace-mental health association and SES as an effect modifier in the gentrification-mental health association. We used cross-sectional Barcelona (Spain) data from 2006, which included perceived mental health status and self-reported depression/anxiety from the Barcelona Health Survey. Greenspace exposure was measured as residential access to (1) all greenspace, (2) greenways and (3) parks in 2006. Census-tract level gentrification was measured using an index including changes in sociodemographic indicators between 1991 and 2006. Logistic regression models revealed that only greenways were associated with better mental health outcomes, with no significant relationship between mental health and parks or all greenspace. Living in gentrifying neighborhoods was protective for depression/anxiety compared to living in non-gentrifying neighborhoods. However, only residents of gentrifiable census tracts benefited from the exposure to greenways. SES was not found to be an effect modifier in the association between gentrification and mental health. Future research should tackle this study's limitations by incorporating a direct measure of displacement in the gentrification status indicator, accounting for qualitative aspects of greenspace and user's perceptions. Gentrification may undermine the health benefits provided by greenspace interventions.


Asunto(s)
Parques Recreativos , Cambio Social , Estudios Transversales , Humanos , Evaluación de Resultado en la Atención de Salud , Características de la Residencia
10.
Expert Rev Neurother ; 21(8): 843-849, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34338566

RESUMEN

INTRODUCTION: Alzheimer's disease (AD) is a chronic neurodegenerative disease and the most common cause of dementia. It has a complex pathophysiology that is not yet completely understood, where multiple central, systemic, and environmental factors play a key role in disease progression. Understanding the multifactorial nature of AD is paramount to formulate new therapies. AREAS COVERED: The authors reviewed the role of the amyloid-ß-binding, antioxidant, and immunomodulatory properties of albumin in AD and the use of therapeutic plasma exchange (PE) in neurology. The results from the Alzheimer Management By Albumin Replacement (AMBAR) trial that combined the use of PE with albumin replacement in patients with mild-to-moderate AD, are also analyzed. EXPERT OPINION: Findings from the AMBAR study provide encouraging results in the treatment of AD with PE and albumin replacement, especially in patients at the moderate stage of the disease, who showed less cognitive decline from baseline compared with placebo in most of the variables analyzed. Further research is warranted to ascertain the possible mechanisms of action underlying these results. Different cohorts of patients that may also benefit from this treatment, such as those with mild cognitive impairment or other types of dementia, could also be the target of additional studies.


Asunto(s)
Albúminas , Enfermedad de Alzheimer , Intercambio Plasmático , Enfermedad de Alzheimer/terapia , Péptidos beta-Amiloides , Biomarcadores , Disfunción Cognitiva , Progresión de la Enfermedad , Humanos
11.
Front Physiol ; 12: 682877, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34447316

RESUMEN

Inflammation and oxidative stress characterize sepsis and determine its severity. In this study, we investigated the relationship between albumin oxidation and sepsis severity in a selected cohort of patients from the Albumin Italian Outcome Study (ALBIOS). A retrospective analysis was conducted on the oxidation forms of human albumin [human mercapto-albumin (HMA), human non-mercapto-albumin form 1 (HNA1) and human non-mercapto-albumin form 2 (HNA2)] in 60 patients with severe sepsis or septic shock and 21 healthy controls. The sepsis patients were randomized (1:1) to treatment with 20% albumin and crystalloid solution or crystalloid solution alone. The albumin oxidation forms were measured at day 1 and day 7. To assess the albumin oxidation forms as a function of oxidative stress, the 60 sepsis patients, regardless of the treatment, were grouped based on baseline sequential organ failure assessment (SOFA) score as surrogate marker of oxidative stress. At day 1, septic patients had significantly lower levels of HMA and higher levels of HNA1 and HNA2 than healthy controls. HMA and HNA1 concentrations were similar in patients treated with albumin or crystalloids at day 1, while HNA2 concentration was significantly greater in albumin-treated patients (p < 0.001). On day 7, HMA was significantly higher in albumin-treated patients, while HNA2 significantly increased only in the crystalloids-treated group, reaching values comparable with the albumin group. When pooling the septic patients regardless of treatment, albumin oxidation was similar across all SOFA groups at day 1, but at day 7 HMA was lower at higher SOFA scores. Mortality rate was independently associated with albumin oxidation levels measured at day 7 (HMA log-rank = 0.027 and HNA2 log-rank = 0.002), irrespective of treatment group. In adjusted regression analyses for 90-day mortality, this effect remained significant for HMA and HNA2. Our data suggest that the oxidation status of albumin is modified according to the time of exposure to oxidative stress (differences between day 1 and day 7). After 7 days of treatment, lower SOFA scores correlate with higher albumin antioxidant capacity. The trend toward a positive effect of albumin treatment, while not statistically significant, warrants further investigation.

12.
Transfus Apher Sci ; 60(3): 103164, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34083161

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative process that inexorably leads to progressive deterioration of cognition function and, ultimately, death. Central pathophysiologic features of AD include the accumulation of extracellular plaques comprised of amyloid-ß peptide (Aß) and the presence of intraneuronal neurofibrillary tangles. However, a large body of evidence suggests that oxidative stress and inflammation are major contributors to the pathogenesis and progression of AD. To date, available pharmacologic treatments are only symptomatic. Clinical trials focused on amyloid and non-amyloid-targeted treatments with small molecule pharmacotherapy and immunotherapies have accumulated a long list of failures. Considering that around 90 % of the circulating Aß is bound to albumin, and that a dynamic equilibrium exists between peripheral and central Aß, plasma exchange with albumin replacement has emerged as a new approach in a multitargeted AD therapeutic strategy (AMBAR Program). In plasma exchange, a patient's plasma is removed by plasmapheresis to eliminate toxic endogenous substances, including Aß and functionally impaired albumin. The fluid replacement used is therapeutic albumin, which acts not only as a plasma volume expander but also has numerous pleiotropic functions (e.g., circulating Aß- binding capacity, transporter, detoxifier, antioxidant) that are clinically relevant for the treatment of AD. Positive results from the AMBAR Program (phase 1, 2, an 2b/3 trials), i.e., slower decline or stabilization of disease symptoms in the most relevant clinical efficacy and safety endpoints, offer a glimmer of hope to both AD patients and caregivers.


Asunto(s)
Albúminas/uso terapéutico , Enfermedad de Alzheimer/terapia , Intercambio Plasmático/métodos , Albúminas/farmacología , Humanos , Modelos Moleculares
13.
FASEB J ; 35(2): e21365, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33496031

RESUMEN

Besides its oncotic power, albumin exerts pleiotropic actions, including binding, transport, and detoxification of endogenous and exogenous molecules, antioxidant activity, and modulation of immune and inflammatory responses. In particular, recent studies have demonstrated that albumin reduces leukocyte cytokine production. Here, we investigated whether albumin also has the ability to protect tissues from the damaging actions of these inflammatory mediators. We circumscribed our investigation to tumor necrosis factor (TNF) α, which exemplifies the connection between immunity and tissue injury. In vivo experiments in analbuminemic mice showed that these mice exhibit a more pronounced response to a model of TNFα-mediated liver injury induced by the administration of lipopolysaccharide (LPS) and D-galactosamine (D-gal). A tissue protective action against LPS/D-gal liver injury was also observed during the administration of human albumin to humanized mice expressing the human genes for albumin and neonatal Fc receptor (hAlb+/+ /hFcRn+/+ ) with preestablished carbon tetrachloride (CCl4 )-induced early cirrhosis. The cytoprotective actions of albumin against TNFα-induced injury were confirmed ex vivo, in precision-cut liver slices, and in vitro, in primary hepatocytes in culture. Albumin protective actions were independent of its scavenging properties and were reproduced by recombinant human albumin expressed in Oryza sativa. Albumin cytoprotection against TNFα injury was related to inhibition of lysosomal cathepsin B leakage accompanied by reductions in mitochondrial cytochrome c release and caspase-3 activity. These data provide evidence that in addition to reducing cytokines, the albumin molecule also has the ability to protect tissues against inflammatory injury.


Asunto(s)
Albúminas/metabolismo , Antiinflamatorios/farmacología , Hepatocitos/metabolismo , Cirrosis Hepática/metabolismo , Factor de Necrosis Tumoral alfa/toxicidad , Albúminas/farmacología , Albúminas/uso terapéutico , Animales , Antiinflamatorios/uso terapéutico , Tetracloruro de Carbono/toxicidad , Células Cultivadas , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Lipopolisacáridos/toxicidad , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/etiología , Masculino , Ratones , Ratones Endogámicos C57BL
14.
Biochem Biophys Rep ; 25: 100889, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33426312

RESUMEN

Epilepsy is a neurological disorder of genetic or environmental origin characterized by recurrent spontaneous seizures. A rodent model of temporal lobe epilepsy is induced by a single administration of pilocarpine, a non-selective cholinergic muscarinic receptor agonist. The molecular changes associated with pilocarpine-induced seizures are still poorly described. Epigenetic multiprotein complexes that regulate gene expression by changing the structure of chromatin impose transcriptional memories. Among the epigenetic enzymes relevant to the epileptogenic process is lysine-specific demethylase 1 (LSD1, KDM1A), which regulates the expression of genes that control neuronal excitability. LSD1 forms complexes with the CoREST family of transcriptional corepressors, which are molecular bridges that bring HDAC1/2 and LSD1 enzymes to deacetylate and demethylate the tail of nucleosomal histone H3. To test the hypothesis that LSD1-complexes are involved in initial modifications associated with pilocarpine-induced epilepsy, we studied the expression of main components of LSD1-complexes and the associated epigenetic marks on isolated neurons and the hippocampus of pilocarpine-treated mice. Using a single injection of 300 mg/kg of pilocarpine and after 24 h, we found that protein levels of LSD1, CoREST2, and HDAC1/2 increased, while CoREST1 decreased in the hippocampus. In addition, we observed increased histone H3 lysine 9 di- and trimethylation (H3K9me2/3) and decreased histone H3 lysine 4 di and trimethylation (H3K4me2/3). Similar findings were observed in cultured hippocampal neurons and HT-22 hippocampal cell line treated with pilocarpine. In conclusion, our data show that muscarinic receptor activation by pilocarpine induces a global repressive state of chromatin and prevalence of LSD1-CoREST2 epigenetic complexes, modifications that could underlie the pathophysiological processes leading to epilepsy.

15.
Sci Transl Med ; 12(566)2020 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-33087502

RESUMEN

Human serum albumin (HSA) is an emerging treatment for preventing excessive systemic inflammation and organ failure(s) in patients with acutely decompensated (AD) cirrhosis. Here, we investigated the molecular mechanisms underlying the immunomodulatory properties of HSA. Administration of HSA to patients with AD cirrhosis with elevated circulating bacterial DNA rich in unmethylated cytosine-phosphate-guanine dideoxynucleotide motifs (CpG-DNA) was associated with reduced plasma cytokine concentrations. In isolated leukocytes, HSA abolished CpG-DNA-induced cytokine expression and release independently of its oncotic and scavenging properties. Similar anti-inflammatory effects were observed with recombinant human albumin. HSA exerted widespread changes on the immune cell transcriptome, specifically in genes related to cytokines and type I interferon responses. Our data revealed that HSA was taken up by leukocytes and internalized in vesicles positively stained with early endosome antigen 1 and colocalized with CpG-DNA in endosomes, where the latter binds to Toll-like receptor 9 (TLR9), its cognate receptor. Furthermore, HSA also inhibited polyinosinic:polycytidylic acid- and lipopolysaccharide-induced interferon regulatory factor 3 phosphorylation and TIR domain-containing adapter-inducing interferon-ß-mediated responses, which are exclusive of endosomal TLR3 and TLR4 signaling, respectively. The immunomodulatory actions of HSA did not compromise leukocyte defensive mechanisms such as phagocytosis, efferocytosis, and intracellular reactive oxygen species production. The in vitro immunomodulatory effects of HSA were confirmed in vivo in analbuminemic humanized neonatal Fc receptor transgenic mice. These findings indicate that HSA internalizes in immune cells and modulates their responses through interaction with endosomal TLR signaling, thus providing a mechanism for the benefits of HSA infusions in patients with cirrhosis.


Asunto(s)
Citocinas , Transducción de Señal , Albúminas , Humanos , Leucocitos , Cirrosis Hepática/tratamiento farmacológico
16.
Crit Care Med ; 48(12): e1350-e1355, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32833695

RESUMEN

OBJECTIVES: Infection by severe acute respiratory syndrome coronavirus-2 can induce uncontrolled systemic inflammation and multiple organ failure. The aim of this study was to evaluate if plasma exchange, through the removal of circulating mediators, can be used as rescue therapy in these patients. DESIGN: Single center case series. SETTING: Local study. SUBJECTS: Four critically ill adults with coronavirus disease 19 pneumonia that failed conventional interventions. INTERVENTIONS: Plasma exchange. Two to six sessions (1.2 plasma volumes). Human albumin (5%) was used as the main replacement fluid. Fresh frozen plasma and immunoglobulins were administered after each session to avoid coagulopathy and hypogammaglobulinemia. MEASUREMENTS AND MAIN RESULTS: Serum markers of inflammation and macrophage activation. All patients showed a dramatic reduction in inflammatory markers, including the main cytokines, and improved severity scores after plasma exchange. All survived to ICU admission. CONCLUSIONS: Plasma exchange mitigates cytokine storm, reverses organ failure, and could improve survival in critically ill patients with coronavirus disease 2019 infection.


Asunto(s)
COVID-19/complicaciones , COVID-19/terapia , Insuficiencia Multiorgánica/etiología , Intercambio Plasmático/métodos , Enfermedad Crítica , Citocinas/biosíntesis , Humanos , Mediadores de Inflamación/metabolismo , Macrófagos/metabolismo , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Índice de Severidad de la Enfermedad
17.
Alzheimers Dement ; 16(10): 1412-1425, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32715623

RESUMEN

INTRODUCTION: This phase 2b/3 trial examined the effects of plasma exchange (PE) in patients with mild-to-moderate Alzheimer's disease (AD). METHODS: Three hundred forty-seven patients (496 screened) were randomized (1:1:1:1) into three PE treatment arms with different doses of albumin and intravenous immunoglobulin replacement (6-week period of weekly conventional PE followed by a 12-month period of monthly low-volume PE), and placebo (sham). RESULTS: PE-treated patients performed significantly better than placebo for the co-primary endpoints: change from baseline of Alzheimer's Disease Cooperative Study-Activities of Daily Living (ADCS-ADL; P = .03; 52% less decline) with a trend for Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog; P = .06; 66% less decline) scores at month 14. Moderate-AD patients (baseline Mini-Mental State Examination [MMSE] 18-21) scored better on ADCS-ADL (P = .002) and ADAS-Cog (P = .05), 61% less decline both. There were no changes in mild-AD patients (MMSE 22-26). PE-treated patients scored better on the Clinical Dementia Rating Sum of Boxes (CDR-sb) (P = .002; 71% less decline) and Alzheimer's Disease Cooperative Study-Clinical Global Impression of Change (ADCS-CGIC) (P < .0001; 100% less decline) scales. DISCUSSION: This trial suggests that PE with albumin replacement could slow cognitive and functional decline in AD, although further studies are warranted.


Asunto(s)
Enfermedad de Alzheimer/terapia , Intercambio Plasmático/métodos , Anciano , Anciano de 80 o más Años , Albúminas/administración & dosificación , Disfunción Cognitiva , Femenino , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Masculino , Persona de Mediana Edad
18.
J Med Case Rep ; 14(1): 72, 2020 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-32552844

RESUMEN

BACKGROUND: Sacrococcygeal teratoma is one of the most frequently prenatally diagnosed neoplasias. Obstetric ultrasound has a role in the diagnosis and management of these tumors during pregnancy. In this report, we describe a multidisciplinary approach in a case of a patient with sacrococcygeal teratomas and preterm delivery, as well as postnatal outcomes. CASE PRESENTATION: A 26-year-old Caucasian woman at 20.3 weeks of gestation with a normal gestational course and no relevant medical or surgical history was referred to our institution with a sacrococcygeal mass diagnosis. Magnetic resonance imaging confirmed the diagnosis of sacrococcygeal teratoma type I according to the Altman classification. Follow-up with ultrasound showed an increase in the size of the mass up to 190 × 150 mm, high Doppler flow, and severe polyhydramnios. At 35.1 weeks of gestation, the patient had premature rupture of membranes, and an emergency cesarean section was performed due to recurrent late decelerations detected by fetal heart rate monitoring. Afterward, surgery was performed successfully at 36 hours of life. Posterior controls revealed normal and healthy child growth. CONCLUSIONS: This case report demonstrates the importance of a multidisciplinary approach to offer the best neonatal outcomes by performing early surgery, as well as the need for follow-up by ultrasound in order to minimize complications by assessing mass growth, Doppler flow, and amniotic fluid.


Asunto(s)
Cesárea , Nacimiento Prematuro , Región Sacrococcígea/diagnóstico por imagen , Teratoma/diagnóstico por imagen , Adulto , Femenino , Rotura Prematura de Membranas Fetales , Humanos , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Grupo de Atención al Paciente , Embarazo , Diagnóstico Prenatal , Región Sacrococcígea/cirugía , Teratoma/cirugía , Ultrasonografía Prenatal
19.
J Thromb Haemost ; 18(8): 1934-1939, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32379931

RESUMEN

BACKGROUND: Emicizumab is an alternative non-factor approach for treating patients with hemophilia A. However, there is a potential risk of thrombotic events when emicizumab is concomitantly administered with pro-hemostatic therapies. OBJECTIVES: To assess the hemostatic effect in vitro when a plasma-derived factor VIII concentrate containing von Willebrand factor (pdFVIII/VWF) was added to hemophilia A plasma (HAp) in combination with emicizumab. METHODS: HAp and HAp with FVIII inhibitors (HAp-i) samples with different concentrations of emicizumab (50 and 100 µg/mL) were combined with activated prothrombin complex concentrate at 0.5 to 1 U/mL, recombinant activated factor VII (rFVIIa) at 0.5 to 7 µg/mL, and pdFVIII/VWF at 0.1 to 4.5 IU/mL. Thrombin generation (TG; thrombin peak and endogenous thrombin potential) was determined using a Calibrated Automated Thrombogram assay. RESULTS: When activated prothrombin complex concentrate was added to HAp and HAp-i with emicizumab, TG dramatically increased (multiplier effect > 4.5×). Addition of rFVIIa to HAp or HAp-i with emicizumab moderately increased TG in a concentration-related manner compared with rFVIIa alone. Addition of pdFVIII/VWF to HAp or HAp-i with emicizumab induced a TG response equivalent to those samples without emicizumab. In an in vitro model of immune tolerance induction with bleeds (HAp-i 15 Bethesda units), combination of pdFVIII/VWF, emicizumab, and rFVIIa did not trigger a multiplying effect on TG. CONCLUSIONS: pdFVIII/VWF showed a non-additive effect on TG when combined in vitro with emicizumab. This finding suggests that emicizumab has limited ability to promote factor X activation in the presence of pdFVIII/VWF, thus reducing the risk of thrombotic events.


Asunto(s)
Anticuerpos Biespecíficos , Hemofilia A , Anticuerpos Monoclonales Humanizados , Factor VIII , Hemofilia A/tratamiento farmacológico , Humanos , Trombina , Factor de von Willebrand
20.
Mol Metab ; 37: 100984, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32229246

RESUMEN

OBJECTIVE: Pancreatic ß-cell failure is central to the development and progression of type 2 diabetes (T2D). The aggregation of human islet amyloid polypeptide (hIAPP) has been associated with pancreatic islet inflammation and dysfunction in T2D. Alpha1-antitrypsin (AAT) is a circulating protease inhibitor with anti-inflammatory properties. Here, we sought to investigate the potential therapeutic effect of AAT treatment in a mouse model characterized by hIAPP overexpression in pancreatic ß-cells. METHODS: Mice overexpressing hIAPP (hIAPP-Tg) in pancreatic ß-cells were used as a model of amyloid-induced ß-cell dysfunction. Glucose homeostasis was evaluated by glucose tolerance tests and insulin secretion assays. Apoptosis and amyloid formation was assessed in hIAPP-Tg mouse islets cultured at high glucose levels. Dissociated islet cells were cocultured with macrophages obtained from the peritoneal cavity. RESULTS: Nontreated hIAPP-Tg mice were glucose intolerant and exhibited impaired insulin secretion. Interestingly, AAT treatment improved glucose tolerance and restored the insulin secretory response to glucose in hIAPP-Tg mice. Moreover, AAT administration normalized the expression of the essential ß-cell genes MafA and Pdx1, which were downregulated in pancreatic islets from hIAPP-Tg mice. AAT prevented the formation of amyloid deposits and apoptosis in hIAPP-Tg islets cultured at high glucose concentrations. Since islet macrophages mediate hIAPP-induced ß-cell dysfunction, we investigated the effect of AAT in cocultures of macrophages and islet cells. AAT prevented hIAPP-induced ß-cell apoptosis in these cocultures without reducing the hIAPP-induced secretion of IL-1ß by macrophages. Remarkably, AAT protected ß-cells against the cytotoxic effects of conditioned medium from hIAPP-treated macrophages. Similarly, AAT also abrogated the cytotoxic effects of exogenous proinflammatory cytokines on pancreatic ß-cells. CONCLUSIONS: These results demonstrate that treatment with AAT improves glucose homeostasis in mice overexpressing hIAPP and protects pancreatic ß-cells from the cytotoxic actions of hIAPP mediated by macrophages. These results support the use of AAT-based therapies to recover pancreatic ß-cell function for the treatment of T2D.


Asunto(s)
Células Secretoras de Insulina/fisiología , Polipéptido Amiloide de los Islotes Pancreáticos/metabolismo , alfa 1-Antitripsina/metabolismo , Amiloide/metabolismo , Animales , Apoptosis , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animales de Enfermedad , Glucosa/metabolismo , Intolerancia a la Glucosa/metabolismo , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Polipéptido Amiloide de los Islotes Pancreáticos/genética , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/fisiología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Transgénicos , alfa 1-Antitripsina/genética
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