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1.
Brain ; 147(5): 1871-1886, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38128553

RESUMEN

Multiple sclerosis is a chronic inflammatory disease in which disability results from the disruption of myelin and axons. During the initial stages of the disease, injured myelin is replaced by mature myelinating oligodendrocytes that differentiate from oligodendrocyte precursor cells. However, myelin repair fails in secondary and chronic progressive stages of the disease and with ageing, as the environment becomes progressively more hostile. This may be attributable to inhibitory molecules in the multiple sclerosis environment including activation of the p38MAPK family of kinases. We explored oligodendrocyte precursor cell differentiation and myelin repair using animals with conditional ablation of p38MAPKγ from oligodendrocyte precursors. We found that p38γMAPK ablation accelerated oligodendrocyte precursor cell differentiation and myelination. This resulted in an increase in both the total number of oligodendrocytes and the migration of progenitors ex vivo and faster remyelination in the cuprizone model of demyelination/remyelination. Consistent with its role as an inhibitor of myelination, p38γMAPK was significantly downregulated as oligodendrocyte precursor cells matured into oligodendrocytes. Notably, p38γMAPK was enriched in multiple sclerosis lesions from patients. Oligodendrocyte progenitors expressed high levels of p38γMAPK in areas of failed remyelination but did not express detectable levels of p38γMAPK in areas where remyelination was apparent. Our data suggest that p38γ could be targeted to improve myelin repair in multiple sclerosis.


Asunto(s)
Esclerosis Múltiple , Vaina de Mielina , Oligodendroglía , Remielinización , Animales , Remielinización/fisiología , Esclerosis Múltiple/patología , Esclerosis Múltiple/metabolismo , Vaina de Mielina/metabolismo , Vaina de Mielina/patología , Ratones , Oligodendroglía/metabolismo , Oligodendroglía/patología , Humanos , Proteína Quinasa 12 Activada por Mitógenos/metabolismo , Proteína Quinasa 12 Activada por Mitógenos/genética , Diferenciación Celular/fisiología , Cuprizona/toxicidad , Ratones Endogámicos C57BL , Masculino , Femenino , Enfermedades Desmielinizantes/patología , Enfermedades Desmielinizantes/metabolismo , Células Precursoras de Oligodendrocitos/metabolismo , Células Precursoras de Oligodendrocitos/patología , Ratones Transgénicos
2.
Arch Microbiol ; 203(7): 4209-4219, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34080042

RESUMEN

Conjugated estrogens, such as 17ß-estradiol-3-sulfate (E2-3S), can be released into aquatic environments through wastewater treatment plants (WWTP). There, they are microbiologically degraded into free estrogens, which can have harmful effects on aquatic wildlife. Here, the degradation of E2-3S in environmental samples taken upstream, downstream and at the effluent of a WWTP was assessed. Sediment and biofilm samples were enriched for E2-3S-degrading microorganisms, yielding a broad diversity of bacterial isolates, including known and novel degraders of estrogens. Since E2-3S-degrading bacteria were also isolated in the sample upstream of the WWTP, the WWTP does not influence the ability of the microbial community to degrade E2-3S.


Asunto(s)
Bacterias , Biodiversidad , Biopelículas , Estradiol/análogos & derivados , Sedimentos Geológicos , Bacterias/clasificación , Bacterias/genética , Estradiol/análisis , Estradiol/metabolismo , Sedimentos Geológicos/microbiología , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua
3.
PLoS Biol ; 14(4): e1002440, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27070899

RESUMEN

Microtubule-based kinesin motors have many cellular functions, including the transport of a variety of cargos. However, unconventional roles have recently emerged, and kinesins have also been reported to act as scaffolding proteins and signaling molecules. In this work, we further extend the notion of unconventional functions for kinesin motor proteins, and we propose that Kif13b kinesin acts as a signaling molecule regulating peripheral nervous system (PNS) and central nervous system (CNS) myelination. In this process, positive and negative signals must be tightly coordinated in time and space to orchestrate myelin biogenesis. Here, we report that in Schwann cells Kif13b positively regulates myelination by promoting p38γ mitogen-activated protein kinase (MAPK)-mediated phosphorylation and ubiquitination of Discs large 1 (Dlg1), a known brake on myelination, which downregulates the phosphatidylinositol 3-kinase (PI3K)/v-AKT murine thymoma viral oncogene homolog (AKT) pathway. Interestingly, Kif13b also negatively regulates Dlg1 stability in oligodendrocytes, in which Dlg1, in contrast to Schwann cells, enhances AKT activation and promotes myelination. Thus, our data indicate that Kif13b is a negative regulator of CNS myelination. In summary, we propose a novel function for the Kif13b kinesin in glial cells as a key component of the PI3K/AKT signaling pathway, which controls myelination in both PNS and CNS.


Asunto(s)
Sistema Nervioso Central/fisiología , Cinesinas/fisiología , Proteínas de la Membrana/fisiología , Vaina de Mielina/fisiología , Proteínas del Tejido Nervioso/fisiología , Sistema Nervioso Periférico/fisiología , Animales , Homólogo 1 de la Proteína Discs Large , Ratones , Ratones Noqueados , Oligodendroglía/metabolismo , Proteínas Asociadas a SAP90-PSD95 , Células de Schwann/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
4.
J Invertebr Pathol ; 120: 59-66, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24907449

RESUMEN

A potential Delia radicum biological control strategy involving cauliflower plantlet inoculation with various fungi was investigated in a series of laboratory and glasshouse experiments. In addition to entomopathogenic fungi, fungi with a high rhizosphere competence and fungi with the ability to survive as saprotrophs in soil were tested. The following fungal species were evaluated in the experiments: Trichoderma atroviride, T. koningiopsis, T. gamsii, Beauveria bassiana, Metharhizium anisopliae, M. brunneum and Clonostachys solani. A commercial carbosulfan-based insecticide was used as a positive control. Additionally, two commercial products, one based on B. bassiana (Naturalis) and one on Bacillus thuringiensis (Delfin) were used as reference biocontrol agents. The aims were (i) to assess the pathogenicity of the selected fungal isolates to Delia radicum, (ii) to evaluate the fungal isolates' rhizosphere competence, with the emphasis on the persistence of the original inoculum on the growing roots, (iii) to assess possible endophytic plant tissue colonization, and (iv) to evaluate potential plant growth stimulating effects of the added inoculi. Significant pathogenicity of tested fungi against Delia radicum was confirmed in in vitro and glasshouse experiments. All tested fungi persisted on cauliflower rhizoplane. More importantly, the added fungi were found on thoroughly washed roots outside the original point of inoculation. This provided us with evidence that our tested fungi could be transferred via or grow with the elongating roots. In addition to colonizing the rhizoplane, some fungi were found inside the plant root or stem tissue, thus exhibiting endophytic characteristics. The importance of fungal ecology as a criterion in appropriate biological control agent selection is discussed.


Asunto(s)
Brassica/microbiología , Dípteros/microbiología , Hongos , Larva/microbiología , Control Biológico de Vectores/métodos , Animales , Enfermedades de las Plantas/microbiología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología
5.
J Asthma Allergy ; 15: 1593-1604, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36387835

RESUMEN

Purpose: Benralizumab effectively reduces severe eosinophilic asthma (SEA) exacerbations in patients with a wide range of baseline blood eosinophil count (BEC). Patients included in real-world studies are often characterized by high mean/median BEC, while patients with BEC close to 300 cells/mm3 are poorly represented. This post hoc analysis from the Italian study ANANKE aims to define the clinical features and corroborate the efficacy of benralizumab in real world in the BEC 300-450 cells/mm3 subset of patients. Patients and Methods: Post hoc analysis of the Italian, multicenter, observational, retrospective real-life study ANANKE (NCT04272463). Baseline clinical and laboratory characteristics were collected in the 12 months prior to benralizumab treatment and presented for a BEC 300-450 cells/mm3 subgroup of patients. Change over time of BEC, annualized exacerbation rate (AER), asthma control (ACT), lung function and oral corticosteroid (OCS) use at 16, 24 and 48 weeks after benralizumab introduction were collected. Results: A total of 164 patients were analyzed, 34 of whom with a BEC of 300-450 cells/mm3. This subgroup was more likely to be female (64.7%), with lower rates of severe exacerbations at baseline when compared to the total population (0.69 vs 1.01). After 48 weeks of benralizumab treatment, the BEC 300-450 subset showed similar reductions in AER (-94.8% vs -92.2%) and OCS use (median dose reduction of 100% in both groups), as well as improvement in ACT score (median scores 22.5 vs 22) and lung function (pre-BD FEV1: +200 mL vs +300 mL) when compared to the total population. No discontinuations for safety reasons were registered. Conclusion: At baseline, apart from lower severe exacerbation rate, the BEC 300-450 cells/mm3 subset of patients is comparable to the total population prescribed with benralizumab. In this real-life study, benralizumab is as effective in BEC 300-450 patients as in the total population.

6.
Neurosci Lett ; 753: 135868, 2021 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-33812927

RESUMEN

Small Rho GTPases such as Cdc42 and Rac1 regulate peripheral myelination during development. Deletion of Rac1 in Schwann cell conditional knockout mice causes a delay in the process of radial sorting, followed by hypomyelination as well as defective PAK1 activation and high number of immature Oct6+ Schwann cells. Rac3 has been shown to have redundant, specific and even opposite functions to Rac1 depending on the cell type, age and other factors. In neuronal cells, evidence suggests that Rac3 may oppose Rac1 by disrupting PAK1-GIT1-Paxillin signaling thus preventing cell differentiation and extension of lamellipodia. Therefore, we tested if these Rho GTPases have similar or opposite functions in Schwann cells, by deleting the genes for both proteins in mice during peripheral myelination. At P30, global deletion of Rac3 alleviates the developmental defects on axonal sorting and hypomyelination that are caused by Schwann cell conditional ablation of Rac1. Moreover, Rac3 deletion also reverses the arrest of Schwann cells at the Oct6+ stage and ameliorates the defects in PAK1 phosphorylation observed in Rac1 deficient mice. This partial rescue of the phenotype declines later on with aging. Since double transgenic animals showed dysmyelination without axonal degeneration at P60, we postulate that this deterioration is not likely due to loss of Rac3 in neurons, but it seems to be a Schwann cell-specific defect in the maintenance of myelin.


Asunto(s)
Vaina de Mielina/metabolismo , Neuropéptidos/metabolismo , Células de Schwann/fisiología , Proteínas de Unión al GTP rac/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Animales , Axones/metabolismo , Diferenciación Celular , Ratones , Ratones Noqueados , Neuropéptidos/genética , Fosforilación , Quinasas p21 Activadas/metabolismo , Proteína de Unión al GTP rac1/genética
7.
PLoS One ; 14(6): e0218166, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31188879

RESUMEN

OBJECTIVE: Non-invasive prenatal testing (NIPT) based on cell-free fetal DNA (cffDNA) is highly accurate in the detection of common fetal autosomal trisomies. Aim of this project was to investigate short-term costs and clinical outcomes of the contingent use of cffDNA for prenatal screening of trisomies 21, 18, 13 within a national health service (NHS). METHODS: An economic analysis was developed from the perspective of the Italian NHS to compare two possible scenarios for managing pregnant women: women managed according to the Standard of Care screening (SoC) vs a cffDNA scenario, where Harmony Prenatal Test was introduced as a second line screening choice for women with an "at risk" result from SoC screening. RESULTS: The introduction of cffDNA as a second line screening test, conditional to a risk ≥ 1:1,000 from SoC screening, showed a 3% increase in the detection of trisomies, with a 71% decrease in the number of invasive tests performed. Total short-term costs (pregnancy management until childbirth) decreased by € 19 million (from € 84.5 to 65.5 million). CONCLUSION: The adoption of the Harmony Prenatal Test in women resulting at risk from SoC screening, implied a greater number of trisomies detection, together with a reduction of the healthcare costs.


Asunto(s)
Ácidos Nucleicos Libres de Células/economía , ADN/economía , Síndrome de Down/economía , Diagnóstico Prenatal/economía , Síndrome de la Trisomía 13/economía , Síndrome de la Trisomía 18/economía , Presupuestos/métodos , Ácidos Nucleicos Libres de Células/genética , ADN/genética , Síndrome de Down/diagnóstico , Síndrome de Down/genética , Femenino , Pruebas Genéticas/economía , Costos de la Atención en Salud , Humanos , Embarazo , Síndrome de la Trisomía 13/diagnóstico , Síndrome de la Trisomía 13/genética , Síndrome de la Trisomía 18/diagnóstico , Síndrome de la Trisomía 18/genética
8.
Nat Neurosci ; 19(7): 879-87, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27273766

RESUMEN

Myelination is essential for nervous system function. Schwann cells interact with neurons and the basal lamina to myelinate axons using known receptors, signals and transcription factors. In contrast, the transcriptional control of axonal sorting and the role of mechanotransduction in myelination are largely unknown. Yap and Taz are effectors of the Hippo pathway that integrate chemical and mechanical signals in cells. We describe a previously unknown role for the Hippo pathway in myelination. Using conditional mutagenesis in mice, we show that Taz is required in Schwann cells for radial sorting and myelination and that Yap is redundant with Taz. Yap and Taz are activated in Schwann cells by mechanical stimuli and regulate Schwann cell proliferation and transcription of basal lamina receptor genes, both necessary for radial sorting of axons and subsequent myelination. These data link transcriptional effectors of the Hippo pathway and of mechanotransduction to myelin formation in Schwann cells.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Vaina de Mielina/metabolismo , Fosfoproteínas/metabolismo , Células de Schwann/metabolismo , Factores de Transcripción/metabolismo , Aciltransferasas , Animales , Axones/fisiología , Axones/ultraestructura , Proteínas de Ciclo Celular , Células Cultivadas , Mecanotransducción Celular/fisiología , Ratones Endogámicos C57BL , Neurogénesis/fisiología , Receptores de Laminina/metabolismo , Células de Schwann/citología , Proteínas Señalizadoras YAP
9.
J Cell Biol ; 208(3): 313-29, 2015 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-25646087

RESUMEN

Fast neural conduction requires accumulation of Na(+) channels at nodes of Ranvier. Dedicated adhesion molecules on myelinating cells and axons govern node organization. Among those, specific laminins and dystroglycan complexes contribute to Na(+) channel clustering at peripheral nodes by unknown mechanisms. We show that in addition to facing the basal lamina, dystroglycan is found near the nodal matrix around axons, binds matrix components, and participates in initial events of nodogenesis. We identify the dystroglycan-ligand perlecan as a novel nodal component and show that dystroglycan is required for the selective accumulation of perlecan at nodes. Perlecan binds the clustering molecule gliomedin and enhances clustering of node of Ranvier components. These data show that proteoglycans have specific roles in peripheral nodes and indicate that peripheral and central axons use similar strategies but different molecules to form nodes of Ranvier. Further, our data indicate that dystroglycan binds free matrix that is not organized in a basal lamina.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/metabolismo , Proteoglicanos de Heparán Sulfato/metabolismo , Nódulos de Ranvier/metabolismo , Animales , Células Cultivadas , Técnicas de Cocultivo , Distroglicanos/metabolismo , Matriz Extracelular/metabolismo , Humanos , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Transgénicos , Microvellosidades/metabolismo , Unión Proteica , Transporte de Proteínas , Proteolisis , Canales de Sodio/metabolismo
10.
PLoS One ; 9(7): e100592, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24984037

RESUMEN

X-ray diffraction has provided extensive information about the arrangement of lipids and proteins in multilamellar myelin. This information has been limited to the abundant inter-nodal regions of the sheath because these regions dominate the scattering when x-ray beams of 100 µm diameter or more are used. Here, we used a 1 µm beam, raster-scanned across a single nerve fiber, to obtain detailed information about the molecular architecture in the nodal, paranodal, and juxtaparanodal regions. Orientation of the lamellar membrane stacks and membrane periodicity varied spatially. In the juxtaparanode-internode, 198-202 Å-period membrane arrays oriented normal to the nerve fiber axis predominated, whereas in the paranode-node, 205-208 Å-period arrays oriented along the fiber direction predominated. In parts of the sheath distal to the node, multiple sets of lamellar reflections were observed at angles to one another, suggesting that the myelin multilayers are deformed at the Schmidt-Lanterman incisures. The calculated electron density of myelin in the different regions exhibited membrane bilayer profiles with varied electron densities at the polar head groups, likely due to different amounts of major myelin proteins (P0 glycoprotein and myelin basic protein). Scattering from the center of the nerve fibers, where the x-rays are incident en face (perpendicular) to the membrane planes, provided information about the lateral distribution of protein. By underscoring the heterogeneity of membrane packing, microdiffraction analysis suggests a powerful new strategy for understanding the underlying molecular foundation of a broad spectrum of myelinopathies dependent on local specializations of myelin structure in both the PNS and CNS.


Asunto(s)
Membrana Celular/química , Proteína Básica de Mielina/química , Proteína P0 de la Mielina/química , Vaina de Mielina/química , Difracción de Rayos X , Animales , Membrana Celular/metabolismo , Ratones , Proteína Básica de Mielina/metabolismo , Proteína P0 de la Mielina/metabolismo , Vaina de Mielina/metabolismo
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