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1.
Nucleic Acids Res ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850156

RESUMEN

Alu elements are non-autonomous Short INterspersed Elements (SINEs) derived from the 7SL RNA gene that are present at over one million copies in human genomic DNA. Alu mobilizes by a mechanism known as retrotransposition, which requires the Long INterspersed Element-1 (LINE-1) ORF2-encoded protein (ORF2p). Here, we demonstrate that HeLa strains differ in their capacity to support Alu retrotransposition. Human Alu elements retrotranspose efficiently in HeLa-HA and HeLa-CCL2 (Alu-permissive) strains, but not in HeLa-JVM or HeLa-H1 (Alu-nonpermissive) strains. A similar pattern of retrotransposition was observed for other 7SL RNA-derived SINEs and tRNA-derived SINEs. In contrast, mammalian LINE-1s, a zebrafish LINE, a human SINE-VNTR-Alu (SVA) element, and an L1 ORF1-containing mRNA can retrotranspose in all four HeLa strains. Using an in vitro reverse transcriptase-based assay, we show that Alu RNAs associate with ORF2p and are converted into cDNAs in both Alu-permissive and Alu-nonpermissive HeLa strains, suggesting that 7SL- and tRNA-derived SINEs use strategies to 'hijack' L1 ORF2p that are distinct from those used by SVA elements and ORF1-containing mRNAs. These data further suggest ORF2p associates with the Alu RNA poly(A) tract in both Alu-permissive and Alu-nonpermissive HeLa strains, but that Alu retrotransposition is blocked after this critical step in Alu-nonpermissive HeLa strains.

2.
J Neurochem ; 168(2): 69-82, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38178803

RESUMEN

N-acetylaspartate (NAA) is an abundant central nervous system amino acid derivative that is tightly coupled to mitochondria and energy metabolism in neurons. A reduced NAA signature is a prominent early pathological biomarker in multiple neurodegenerative diseases and becomes progressively more pronounced as disease advances. Because NAA synthesis requires aspartate drawn directly from mitochondria, we argued that this process is in direct competition with oxidative phosphorylation for substrate and that sustained high levels of NAA synthesis would be incompatible with pathological energy crisis. We show here that over-expression of the rate-limiting NAA synthetic enzyme in the hippocampus of the 5x familial Alzheimer's disease (5xFAD) mouse results in an exaggerated pathological ATP deficit and accelerated cognitive decline. Over-expression of NAA synthase did not increase amyloid burden or result in cell loss but did significantly deplete mitochondrial aspartate and impair the ability of mitochondria to oxidize glutamate for adenosine triphosphate (ATP) synthesis. These results define NAA as a sink for energetic substrate and suggest initial pathological reductions in NAA are part of a response to energetic crisis designed to preserve substrate bioavailability for mitochondrial ATP synthesis.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Ratones , Animales , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Ácido Aspártico/metabolismo , Adenosina Trifosfato/metabolismo
3.
Eur J Neurol ; 30(10): 3032-3046, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37340928

RESUMEN

BACKGROUND: Neuroinflammation in the cerebral cortex of patients who died with liver cirrhosis and neuroinflammation, and neuronal death in the cerebellum of patients who died with steatohepatitis or cirrhosis, were reported. Hippocampal neuroinflammation could contribute to cognitive decline in patients with liver disease, but this has yet to be studied. The study aims were to assess if hippocampus from patients who died with steatohepatitis or cirrhosis showed: (i) glial activation, (ii) altered cytokine content, (iii) immune cell infiltration, (iv) neuronal apoptosis and (v) neuronal loss. METHODS: Post-mortem hippocampus was obtained from 6 controls, 19 patients with steatohepatitis (SH) and 4 patients with liver cirrhosis. SH patients were divided into SH1 (n = 9), SH2 (n = 6) and SH3 (n = 4) groups depending on disease severity. Glial activation, IL-1ß and TNFα content, CD4 lymphocyte and monocyte infiltration, neuronal apoptosis and neuronal loss were analyzed by immunohistochemistry. RESULTS: Patients who died in SH1 showed astrocyte activation, whereas those who died in SH2 also showed microglial activation, CD4 lymphocyte and monocyte infiltration, neuronal apoptosis and neuronal loss. These changes remained in patients in SH3, who also showed increased IL-1ß and TNFα. Patients who died of liver cirrhosis did not show CD4 lymphocyte infiltration, neuronal apoptosis or increase in TNFα, but still showed glial activation, increased IL-1ß and neuronal loss. CONCLUSIONS: Patients with steatohepatitis showed glial activation, immune cell infiltration, apoptosis and neuronal loss. Glial activation and neuronal loss remained in cirrhotic patients. This may explain the irreversibility of some cognitive alterations in hepatic encephalopathy. Cognitive reserve may contribute to different grades of cognitive impairment despite similar neuronal loss.


Asunto(s)
Hígado Graso , Factor de Necrosis Tumoral alfa , Humanos , Enfermedades Neuroinflamatorias , Cirrosis Hepática/complicaciones , Hígado Graso/patología , Hipocampo/patología
4.
Exp Cell Res ; 403(1): 112594, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33823179

RESUMEN

COVID-19 was declared an international public health emergency in January, and a pandemic in March of 2020. There are over 125 million confirmed COVID-19 cases that have caused over 2.7 million deaths worldwide as of March 2021. COVID-19 is caused by the SARS-CoV-2 virus. SARS-CoV-2 presents a surface "spike" protein that binds to the ACE2 receptor to infect host cells. In addition to the respiratory tract, SARS-Cov-2 can also infect cells of the oral mucosa, which also express the ACE2 receptor. The spike and ACE2 proteins are highly glycosylated with sialic acid modifications that direct viral-host interactions and infection. Maackia amurensis seed lectin (MASL) has a strong affinity for sialic acid modified proteins and can be used as an antiviral agent. Here, we report that MASL targets the ACE2 receptor, decreases ACE2 expression and glycosylation, suppresses binding of the SARS-CoV-2 spike protein, and decreases expression of inflammatory mediators by oral epithelial cells that cause ARDS in COVID-19 patients. In addition, we report that MASL also inhibits SARS-CoV-2 infection of kidney epithelial cells in culture. This work identifies MASL as an agent with potential to inhibit SARS-CoV-2 infection and COVID-19 related inflammatory syndromes.


Asunto(s)
Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , Lectinas/farmacología , Boca/efectos de los fármacos , SARS-CoV-2/efectos de los fármacos , Glicoproteína de la Espiga del Coronavirus/efectos de los fármacos , Progresión de la Enfermedad , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Interacciones Microbiota-Huesped/efectos de los fármacos , Humanos , Maackia/metabolismo , SARS-CoV-2/patogenicidad , Glicoproteína de la Espiga del Coronavirus/metabolismo
5.
J Evol Biol ; 34(10): 1624-1636, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34378263

RESUMEN

Understanding how species can thrive in a range of environments is a central challenge for evolutionary ecology. There is strong evidence for local adaptation along large-scale ecological clines in insects. However, potential adaptation among neighbouring populations differing in their environment has been studied much less. We used RAD sequencing to quantify genetic divergence and clustering of ten populations of the field cricket Gryllus campestris in the Cantabrian Mountains of northern Spain, and an outgroup on the inland plain. Our populations were chosen to represent replicate high and low altitude habitats. We identified genetic clusters that include both high and low altitude populations indicating that the two habitat types do not hold ancestrally distinct lineages. Using common-garden rearing experiments to remove environmental effects, we found evidence for differences between high and low altitude populations in physiological and life-history traits. As predicted by the local adaptation hypothesis, crickets with parents from cooler (high altitude) populations recovered from periods of extreme cooling more rapidly than those with parents from warmer (low altitude) populations. Growth rates also differed between offspring from high and low altitude populations. However, contrary to our prediction that crickets from high altitudes would grow faster, the most striking difference was that at high temperatures, growth was fastest in individuals from low altitudes. Our findings reveal that populations a few tens of kilometres apart have independently evolved adaptations to their environment. This suggests that local adaptation in a range of traits may be commonplace even in mobile invertebrates at scales of a small fraction of species' distributions.


Asunto(s)
Gryllidae , Aclimatación , Adaptación Fisiológica/genética , Altitud , Animales , Evolución Biológica , Gryllidae/genética , Humanos
6.
Monaldi Arch Chest Dis ; 92(3)2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-34964575

RESUMEN

Six minute walk test (6MWT) is a field exercise test widely used in clinical practice, both in adults and in pediatric patients. The primary aim of the study is to evaluate the physical performance of the subjects and compare them with the predicted Italian values. The secondary aim is to verify the possible relationship between the 6MWT distance (6MWD) and the clinical variables of the sample. Italian children between 6-11 years affected by CF were recruited from 9 regional centers for CF. Short questionnaire assessments about their health state and physical activity routine was administered. Anthropometric characteristics were measured before the test and, peripheral oxygen saturation (SpO2), heart and respiratory rate were measured before and after a 6-minute walk test. The tests were performed according to the American Thoracic Society (ATS) guidelines. 6MWD was compared with the predicted distance calculated by the reference equation for healthy subjects of the same age. A total of 132 children were recruited (70 male) and completed the assessment. The mean (±SD) for 6MWD was 557.4 (±69.9), male = 551.4 (±80.0), female = 560.4 (±63.3), however the predicted distance mean was 605 m. A total of 101(76.5%) subjects practice regular physical activity. A total of 31 (23%) had a FEV1 lower than their lower limits of normal (LLN). Functional performance on the 6MWT was poorer among the CF patients than among the predicted distance estimated with Italian values. The correlation with the amount of physical activity and 6MWD has been verified.


Asunto(s)
Fibrosis Quística , Adulto , Niño , Fibrosis Quística/diagnóstico , Fibrosis Quística/epidemiología , Ejercicio Físico , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Prueba de Paso , Caminata
7.
J Hepatol ; 73(3): 582-592, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-30654069

RESUMEN

BACKGROUND & AIMS: Chronic hyperammonemia induces neuroinflammation which mediates cognitive impairment. How hyperammonemia induces neuroinflammation remains unclear. We aimed to assess whether: chronic hyperammonemia induces peripheral inflammation, and whether this then contributes to neuroinflammation, altered neurotransmission and impaired spatial learning - before assessing whether this neuroinflammation and impairment is reversible following hyperammonemia elimination or treatment of peripheral inflammation with anti-TNF-α. METHODS: Chronic hyperammonemia was induced by feeding rats an ammonia-containing diet. Peripheral inflammation was analyzed by measuring PGE2, TNF-α, IL-6 and IL-10. We tested whether chronic anti-TNF-α treatment improves peripheral inflammation, neuroinflammation, membrane expression of glutamate receptors in the hippocampus and spatial learning. RESULTS: Hyperammonemic rats show a rapid and reversible induction of peripheral inflammation, with increased pro-inflammatory PGE2, TNF-α and IL-6, followed at around 10 days by reduced anti-inflammatory IL-10. Peripheral anti-TNF-α treatment prevents peripheral inflammation induction and the increase in IL-1b and TNF-α and microglia activation in hippocampus of the rats, which remain hyperammonemic. This is associated with prevention of the altered membrane expression of glutamate receptors and of the impairment of spatial memory assessed in the radial and Morris water mazes. CONCLUSIONS: This report unveils a new mechanism by which chronic hyperammonemia induces neurological alterations: induction of peripheral inflammation. This suggests that reducing peripheral inflammation by safe procedures would improve cognitive function in patients with minimal hepatic encephalopathy. LAY SUMMARY: This article unveils a new mechanism by which chronic hyperammonemia induces cognitive impairment in rats: chronic hyperammonemia per se induces peripheral inflammation, which mediates many of its effects on the brain, including induction of neuroinflammation, which alters neurotransmission, leading to cognitive impairment. It is also shown that reducing peripheral inflammation by treating rats with anti-TNF-α, which does not cross the blood-brain barrier, prevents hyperammonemia-induced neuroinflammation, alterations in neurotransmission and cognitive impairment.


Asunto(s)
Antiinflamatorios/administración & dosificación , Disfunción Cognitiva/etiología , Disfunción Cognitiva/prevención & control , Hiperamonemia/complicaciones , Infliximab/administración & dosificación , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Disfunción Cognitiva/sangre , Modelos Animales de Enfermedad , Encefalopatía Hepática/tratamiento farmacológico , Encefalopatía Hepática/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/etiología , Inflamación/metabolismo , Masculino , Memoria/efectos de los fármacos , Ratas , Ratas Wistar , Aprendizaje Espacial/efectos de los fármacos , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/sangre
8.
Pharmacogenomics J ; 20(1): 136-158, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31616044

RESUMEN

Colorectal cancer is one of the leading causes of cancer death worldwide. Over the last decades, several studies have shown that tumor-related genomic alterations predict tumor prognosis, drug response, and toxicity. These observations have led to the development of several therapies based on individual genomic profiles. As part of these approaches, pharmacogenomics analyses genomic alterations which may predict an efficient therapeutic response. Studying these mutations as biomarkers for predicting drug response is of a great interest to improve precision medicine. We conduct a comprehensive review of the main pharmacogenomics biomarkers and genomic alterations affecting enzyme activity, transporter capacity, channels, and receptors; and therefore the new advances in CRC precision medicine to select the best therapeutic strategy in populations worldwide, with a focus on Latin America.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Frecuencia de los Genes/genética , Redes Reguladoras de Genes/genética , Farmacogenética/métodos , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Frecuencia de los Genes/efectos de los fármacos , Redes Reguladoras de Genes/efectos de los fármacos , Humanos
9.
PLoS Comput Biol ; 15(5): e1006918, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31071077

RESUMEN

Scientific data recording and reporting systems are of a great interest for endorsing reproducibility and transparency practices among the scientific community. Current research generates large datasets that can no longer be documented using paper lab notebooks (PLNs). In this regard, electronic laboratory notebooks (ELNs) could be a promising solution to replace PLNs and promote scientific reproducibility and transparency. We previously analyzed five ELNs and performed two survey-based studies to implement an ELN in a biomedical research institute. Among the ELNs tested, we found that Microsoft OneNote presents numerous features related to ELN best functionalities. In addition, both surveyed groups preferred OneNote over a scientifically designed ELN (PerkinElmer Elements). However, OneNote remains a general note-taking application and has not been designed for scientific purposes. We therefore provide a quick guide to adapt OneNote to an ELN workflow that can also be adjusted to other nonscientific ELNs.


Asunto(s)
Almacenamiento y Recuperación de la Información/métodos , Proyectos de Investigación/tendencias , Investigación Biomédica , Laboratorios , Reproducibilidad de los Resultados , Programas Informáticos , Flujo de Trabajo
10.
J Transl Med ; 17(1): 293, 2019 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-31462286

RESUMEN

BACKGROUND: Minimal hepatic encephalopathy (MHE) in cirrhotic patients is associated with specific changes in parameters of the immune system reflecting a more pro-inflammatory environment than in patients without MHE. The aims of this work were to assess the effects of rifaximin treatment of cirrhotic patients with MHE on: (1) MHE; (2) intermediate (CD14++CD16+) pro-inflammatory monocytes; (3) expression of early activation marker CD69 in T lymphocytes; (4) autoreactive CD4+CD28- T lymphocytes; (5) differentiation of CD4+ T lymphocytes to Th follicular and Th22; (6) serum IgG levels; and (7) levels of some pro-inflammatory cytokines. METHODS: These parameters were measured by immunophenotyping and cytokine profile analysis in 30 controls without liver disease, 30 cirrhotic patients without MHE and 22 patients with MHE. Patients with MHE were treated with rifaximin and the same parameters were measured at 3 and 6 months of treatment. We assessed if changes in these parameters are different in patients who improve MHE (responders) and those who remain in MHE (non-responders). RESULTS: Rifaximin improved MHE in 59% of patients with MHE. In these responder patients rifaximin normalized all alterations in the immune system measured while in non-responders it normalizes only IL-6, CCL20, and differentiation of T lymphocytes to Th22. Non-responder patients do not show increased expression of CD69 before treatment. CONCLUSIONS: Rifaximin normalizes changes in the immune system in patients who improve MHE but not in non-responders. Some alterations before treatment are different in responders and non-responders. Understanding these differences may identify predictors of the response of MHE to rifaximin.


Asunto(s)
Encefalopatía Hepática/tratamiento farmacológico , Encefalopatía Hepática/inmunología , Inmunofenotipificación , Rifaximina/uso terapéutico , Citocinas/sangre , Regulación de la Expresión Génica/efectos de los fármacos , Encefalopatía Hepática/sangre , Humanos , Inmunoglobulina G/sangre , Monocitos/efectos de los fármacos , Psicometría , Rifaximina/farmacología , Linfocitos T/efectos de los fármacos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
11.
Neurobiol Dis ; 96: 323-334, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27717881

RESUMEN

Breakdown of neuro-glial N-acetyl-aspartate (NAA) metabolism results in the failure of developmental myelination, manifest in the congenital pediatric leukodystrophy Canavan disease caused by mutations to the sole NAA catabolizing enzyme aspartoacylase. Canavan disease is a major point of focus for efforts to define NAA function, with available evidence suggesting NAA serves as an acetyl donor for fatty acid synthesis during myelination. Elevated NAA is a diagnostic hallmark of Canavan disease, which contrasts with a broad spectrum of alternative neurodegenerative contexts in which levels of NAA are inversely proportional to pathological progression. Recently generated data in the nur7 mouse model of Canavan disease suggests loss of aspartoacylase function results in compromised energetic integrity prior to oligodendrocyte death, abnormalities in myelin content, spongiform degeneration, and motor deficit. The present study utilized a next-generation "oligotropic" adeno-associated virus vector (AAV-Olig001) to quantitatively assess the impact of aspartoacylase reconstitution on developmental myelination. AAV-Olig001-aspartoacylase promoted normalization of NAA, increased bioavailable acetyl-CoA, and restored energetic balance within a window of postnatal development preceding gross histopathology and deteriorating motor function. Long-term effects included increased oligodendrocyte numbers, a global increase in myelination, reversal of vacuolation, and rescue of motor function. Effects on brain energy observed following AAV-Olig001-aspartoacylase gene therapy are shown to be consistent with a metabolic profile observed in mild cases of Canavan disease, implicating NAA in the maintenance of energetic integrity during myelination via oligodendroglial aspartoacylase.


Asunto(s)
Amidohidrolasas/metabolismo , Ácido Aspártico/análogos & derivados , Encéfalo/enzimología , Enfermedad de Canavan/patología , Vaina de Mielina/fisiología , Oligodendroglía/enzimología , Amidohidrolasas/genética , Animales , Ácido Aspártico/genética , Ácido Aspártico/metabolismo , Proteínas Relacionadas con la Autofagia , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Encéfalo/patología , Enfermedad de Canavan/complicaciones , Enfermedad de Canavan/diagnóstico por imagen , Enfermedad de Canavan/genética , Niño , Preescolar , Dependovirus/genética , Progresión de la Enfermedad , Metabolismo Energético/genética , Femenino , Regulación de la Expresión Génica/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Humanos , Lactante , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Ratones , Ratones Transgénicos , Trastornos del Movimiento/etiología , Proteína Básica de Mielina/metabolismo , Enfermedades Neurodegenerativas/etiología , Enfermedades Neurodegenerativas/genética
12.
Mol Cell Neurosci ; 65: 143-52, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25766789

RESUMEN

N-acetylaspartate (NAA) provides a non-invasive clinical index of neuronal metabolic integrity across the entire neurodegenerative spectrum. While NAA function is not comprehensively defined, reductions in the brain are associated with compromised mitochondrial metabolism and are tightly linked to ATP. We have undertaken an analysis of abnormalities in NAA during early stage pathology in the 5xFAD mouse model of familial Alzheimer's disease and show here that dysregulated expression of the gene encoding for the rate-limiting NAA synthetic enzyme (Nat8L) is associated with deficits in mitochondrial oxidative phosphorylation in this model system. Downreguation of Nat8L is particularly pronounced in the 5xFAD hippocampus, and is preceded by a significant upregulation of oligodendrocytic aspartoacylase (aspa), which encodes for the sole known NAA-catabolizing enzyme in the brain. Reductions in 5xFAD NAA and Nat8L cannot be accounted for by discrepancies in either neuron content or activity of the substrate-providing malate-aspartate shuttle, thereby implicating transcriptional regulation in a coordinated response to pathological energetic crisis. A central role for ASPA in this response is supported by a parallel developmental analysis showing highly significant increases in Nat8L expression in an ASPA-null mouse model during a period of early postnatal development normally punctuated by the transcriptional upregulation of aspa. These results provide preliminary evidence of a signaling mechanism in Alzheimer's disease that involves cross talk between neurons and oligodendrocytes, and suggest that ASPA acts to negatively regulate Nat8L expression. This mechanism is proposed to be a fundamental means by which the brain conserves available substrate during energy crises.


Asunto(s)
Acetiltransferasas/metabolismo , Enfermedad de Alzheimer/metabolismo , Neuroglía/metabolismo , Neuronas/metabolismo , Fosforilación Oxidativa , Transcripción Genética , Acetiltransferasas/genética , Amidohidrolasas/genética , Amidohidrolasas/metabolismo , Animales , Regulación hacia Abajo , Hipocampo/citología , Hipocampo/metabolismo , Ratones , ARN Mensajero/genética , ARN Mensajero/metabolismo
13.
Traffic ; 13(8): 1083-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22519601

RESUMEN

The widely used botulinum neurotoxin A (BoNT/A) blocks neurotransmission via cleavage of the synaptic protein SNAP-25 (synaptosomal-associated protein of 25 kDa). Recent evidence demonstrating long-distance propagation of SNAP-25 proteolysis has challenged the idea that BoNT/A remains localized to the injection site. However, the extent to which distant neuronal networks are impacted by BoNT/A retrograde trafficking remains unknown. Importantly, no studies have addressed whether SNAP-25 cleavage translates into structural and functional changes in distant intoxicated synapses. Here we show that the BoNT/A injections into the adult rat optic tectum result in SNAP-25 cleavage in retinal neurons two synapses away from the injection site, such as rod bipolar cells and photoreceptors. Retinal endings displaying cleaved SNAP-25 were enlarged and contained an abnormally high number of synaptic vesicles, indicating impaired exocytosis. Tectal injection of BoNT/A in rat pups resulted in appearance of truncated-SNAP-25 in cholinergic amacrine cells. Functional imaging with calcium indicators showed a clear reduction in cholinergic-driven wave activity, demonstrating impairments in neurotransmission. These data provide the first evidence for functional effects of the retrograde trafficking of BoNT/A, and open the possibility of using BoNT/A fragments as drug delivery vehicles targeting the central nervous system.


Asunto(s)
Toxinas Botulínicas Tipo A/farmacología , Transmisión Sináptica/efectos de los fármacos , Vesículas Sinápticas/metabolismo , Proteína 25 Asociada a Sinaptosomas/antagonistas & inhibidores , Animales , Señalización del Calcio , Ratas , Ratas Long-Evans , Neuronas Retinianas/efectos de los fármacos , Neuronas Retinianas/metabolismo , Neuronas Retinianas/ultraestructura , Transmisión Sináptica/fisiología , Vesículas Sinápticas/efectos de los fármacos , Vesículas Sinápticas/ultraestructura , Proteína 25 Asociada a Sinaptosomas/metabolismo
14.
J Inherit Metab Dis ; 37(3): 369-81, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24288037

RESUMEN

The inherited pediatric leukodystrophy Canavan disease is characterized by dysmyelination and severe spongiform degeneration, and is currently refractory to treatment. A definitive understanding of core disease mechanisms is lacking, but pathology is believed to result at least in part compromised fatty acid synthesis during myelination. Recent evidence generated in an animal model suggests that the breakdown of N-acetylaspartate metabolism in CD results in a heightened coupling of fatty acid synthesis to oligodendrocyte oxidative metabolism during the early stages of myelination, thereby causing acute oxidative stress. We present here the results of a dietary intervention designed to support oxidative integrity during developmental myelination in the nur7 mouse model of Canavan disease. Provision of the odd carbon triglyceride triheptanoin to neonatal nur7 mice reduced oxidative stress, promoted long-term oligodendrocyte survival, and increased myelin in the brain. Improvements in oligodendrocyte survival and myelination were associated with a highly significant reduction in spongiform degeneration and improved motor function in triheptanoin treated mice. Initiation of triheptanoin treatment in older animals resulted in markedly more modest effects on these same pathological indices, indicating a window of therapeutic intervention that corresponds with developmental myelination. These results support the targeting of oxidative integrity at early stages of Canavan disease, and provide a foundation for the clinical development of a non-invasive dietary triheptanoin treatment regimen.


Asunto(s)
Amidohidrolasas/genética , Enfermedad de Canavan/terapia , Vaina de Mielina/fisiología , Oligodendroglía/patología , Triglicéridos/administración & dosificación , Adenosina Trifosfato/metabolismo , Animales , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Enfermedad de Canavan/patología , Enfermedad de Canavan/fisiopatología , Modelos Animales de Enfermedad , Ratones
15.
bioRxiv ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38746229

RESUMEN

Alu elements are non-autonomous Short INterspersed Elements (SINEs) derived from the 7SL RNA gene that are present at over one million copies in human genomic DNA. Alu mobilizes by a mechanism known as retrotransposition, which requires the Long INterspersed Element-1 (LINE-1 or L1) ORF2 -encoded protein (ORF2p). Here, we demonstrate that HeLa strains differ in their capacity to support Alu retrotransposition. Human Alu elements retrotranspose efficiently in HeLa-HA and HeLa-CCL2 ( Alu -permissive) strains, but not in HeLa-JVM or HeLa-H1 ( Alu -nonpermissive) strains. A similar pattern of retrotransposition was observed for other 7SL RNA -derived SINEs and tRNA -derived SINEs. In contrast, mammalian LINE-1s, a zebrafish LINE, a human SINE-VNTR - Alu ( SVA ) element, and an L1 ORF1 -containing messenger RNA can retrotranspose in all four HeLa strains. Using an in vitro reverse transcriptase-based assay, we show that Alu RNAs associate with ORF2p and are converted into cDNAs in both Alu -permissive and Alu -nonpermissive HeLa strains, suggesting that 7SL - and tRNA -derived SINE RNAs use strategies to 'hijack' L1 ORF2p that are distinct from those used by SVA elements and ORF1 -containing mRNAs. These data further suggest ORF2p associates with the Alu RNA poly(A) tract in both Alu -permissive and Alu -nonpermissive HeLa strains, but that Alu retrotransposition is blocked after this critical step in Alu -nonpermissive HeLa strains.

16.
iScience ; 26(11): 108143, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37915599

RESUMEN

Studies have reported increased intestinal permeability in multiple sclerosis (MS) patients and its mouse model experimental autoimmune encephalomyelitis (EAE). However, the mechanisms driving increased intestinal permeability that in turn exacerbate neuroinflammation during EAE remain unclear. Here we showed that vancomycin preserved the integrity of the intestinal barrier, while also suppressing gut trypsin activity, enhancing the relative abundance of specific Lactobacilli and ameliorating disease during EAE. Furthermore, Lactobacilli enriched in the gut of vancomycin-treated EAE mice at day 3 post immunization negatively correlated with gut trypsin activity and EAE severity. In untreated EAE mice, we observed increased intestinal permeability and increased intestinal protease activated receptor 2 (PAR2) expression at day 3 post immunization. Prior studies have shown that trypsin increases intestinal permeability by activating PAR2. Our results suggest that the interaction between intestinal PAR2 and trypsin may be a key modulator of intestinal permeability and disease severity during EAE.

17.
J Cell Mol Med ; 16(12): 3009-21, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22947336

RESUMEN

To further contribute to the understanding of multiple myeloma, we have focused our research interests on the mechanisms by which tumour plasma cells have a higher survival rate than normal plasma cells. In this article, we study the expression profile of genes involved in the regulation and protection of telomere length, telomerase activity and apoptosis in samples from patients with monoclonal gammopathy of undetermined significance, smouldering multiple myeloma, multiple myeloma (MM) and plasma cell leukaemia (PCL), as well as several human myeloma cell lines (HMCLs). Using conventional cytogenetic and fluorescence in situ hybridization studies, we identified a high number of telomeric associations (TAs). Moreover, telomere length measurements by terminal restriction fragment (TRF) assay showed a shorter mean TRF peak value, with a consistent correlation with the number of TAs. Using gene expression arrays and quantitative PCR we identified the hTERT gene together with 16 other genes directly involved in telomere length maintenance: HSPA9, KRAS, RB1, members of the Small nucleolar ribonucleoproteins family, A/B subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins, and 14-3-3 family. The expression levels of these genes were even higher than those in human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs), which have unlimited proliferation capacity. In conclusion, the gene signature suggests that MM tumour cells are able to maintain stable short telomere lengths without exceeding the short critical length, allowing cell divisions to continue. We propose that this could be a mechanism contributing to MM tumour cells expansion in the bone marrow (BM).


Asunto(s)
Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Homeostasis del Telómero/genética , Telómero/genética , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Inestabilidad Cromosómica , Células Madre Embrionarias/metabolismo , Femenino , Perfilación de la Expresión Génica , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Ribonucleoproteínas Nucleares Heterogéneas/genética , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Leucemia de Células Plasmáticas/genética , Leucemia de Células Plasmáticas/metabolismo , Masculino , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Gammopatía Monoclonal de Relevancia Indeterminada/genética , Gammopatía Monoclonal de Relevancia Indeterminada/metabolismo , Células Plasmáticas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas p21(ras) , Proteína de Retinoblastoma/genética , Proteína de Retinoblastoma/metabolismo , Ribonucleoproteínas Nucleolares Pequeñas/genética , Ribonucleoproteínas Nucleolares Pequeñas/metabolismo , Telomerasa/genética , Telomerasa/metabolismo , Telómero/metabolismo , Transcriptoma , Proteínas ras/genética , Proteínas ras/metabolismo
18.
Ann Surg Oncol ; 19(7): 2367-79, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22395973

RESUMEN

BACKGROUND: Glioblastoma multiforme (GBM) is the most common primary tumor of the central nervous system in adults. Patients with GBM have few treatment options, and their disease is invariably fatal. Molecularly targeted agents offer the potential to improve patient treatment; however, the use of these will require a fuller understanding of the genetic changes in this complex tumor. METHODS: We analyzed a series of 32 patients with GBM with array comparative genomic hybridization in combination with gene expression analysis. We focused on the recurrent breakpoints found by spectral karyotyping (SKY). RESULTS: By SKY we identified 23 recurrent breakpoints of the 202 translocations found in GBM cases. Gains and losses were identified in chromosomal regions close to the breakpoints by array comparative genomic hybridization. We evaluated the genes located in the regions involved in the breakpoints in depth. A list of 406 genes that showed a level of expression significantly different between patients and control subjects was selected to determine their effect on survival. Genes CACNA2D3, PPP2R2B, SIK, MAST3, PROM1, and PPP6C were significantly associated with shorter survival (median 200 days vs. 450 days, P≤0.03). CONCLUSIONS: We present a list of genes located in regions of breakpoints that could be grounds for future studies to determine whether they are crucial in the pathogenesis of this type of tumor, and we provide a list of six genes associated with the clinical outcome of patients with GBM.


Asunto(s)
Biomarcadores de Tumor/genética , Aberraciones Cromosómicas , Hibridación Genómica Comparativa , Perfilación de la Expresión Génica , Glioblastoma/genética , Glioblastoma/patología , Cariotipificación Espectral , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Glioblastoma/mortalidad , Humanos , Cariotipificación , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Riesgo , Tasa de Supervivencia
19.
Blood ; 116(15): e56-65, 2010 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-20616218

RESUMEN

To obtain a comprehensive genomic profile of presenting multiple myeloma cases we performed high-resolution single nucleotide polymorphism mapping array analysis in 114 samples alongside 258 samples analyzed by U133 Plus 2.0 expression array (Affymetrix). We examined DNA copy number alterations and loss of heterozygosity (LOH) to define the spectrum of minimally deleted regions in which relevant genes of interest can be found. The most frequent deletions are located at 1p (30%), 6q (33%), 8p (25%), 12p (15%), 13q (59%), 14q (39%), 16q (35%), 17p (7%), 20 (12%), and 22 (18%). In addition, copy number-neutral LOH, or uniparental disomy, was also prevalent on 1q (8%), 16q (9%), and X (20%), and was associated with regions of gain and loss. Based on fluorescence in situ hybridization and expression quartile analysis, genes of prognostic importance were found to be located at 1p (FAF1, CDKN2C), 1q (ANP32E), and 17p (TP53). In addition, we identified common homozygously deleted genes that have functions relevant to myeloma biology. Taken together, these analyses indicate that the crucial pathways in myeloma pathogenesis include the nuclear factor-κB pathway, apoptosis, cell-cycle regulation, Wnt signaling, and histone modifications. This study was registered at http://isrctn.org as ISRCTN68454111.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos/genética , Variaciones en el Número de Copia de ADN/genética , Mieloma Múltiple/genética , Anciano , Deleción Cromosómica , Femenino , Reordenamiento Génico de Cadena Pesada de Linfocito B , Humanos , Hibridación Fluorescente in Situ , Estimación de Kaplan-Meier , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/inmunología , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Pronóstico , Translocación Genética , Disomía Uniparental
20.
Biomedicines ; 10(6)2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35740285

RESUMEN

Patients with non-alcoholic fatty liver disease (NAFLD) may show mild cognitive impairment. Neuroinflammation in the hippocampus mediates cognitive impairment in rat models of minimal hepatic encephalopathy (MHE). Treatment with rifaximin reverses cognitive impairment in a large proportion of cirrhotic patients with MHE. However, the underlying mechanisms remain unclear. The aims of this work were to assess if rats with mild liver damage, as a model of NAFLD, show neuroinflammation in the hippocampus and impaired cognitive function, if treatment with rifaximin reverses it, and to study the underlying mechanisms. Mild liver damage was induced with carbon-tetrachloride. Infiltration of immune cells, glial activation, and cytokine expression, as well as glutamate receptors expression in the hippocampus and cognitive function were assessed. We assessed the effects of daily treatment with rifaximin on the alterations showed by these rats. Rats with mild liver damage showed hippocampal neuroinflammation, reduced membrane expression of glutamate N-methyl-D-aspartate (NMDA) receptor subunits, and impaired spatial memory. Increased C-C Motif Chemokine Ligand 2 (CCL2), infiltration of monocytes, microglia activation, and increased tumor necrosis factor α (TNFα) were reversed by rifaximin, that normalized NMDA receptor expression and improved spatial memory. Thus, rifaximin reduces neuroinflammation and improves cognitive function in rats with mild liver damage, being a promising therapy for patients with NAFLD showing mild cognitive impairment.

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