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1.
Cell ; 186(21): 4546-4566.e27, 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37769657

RESUMEN

Neutrophils are abundant immune cells in the circulation and frequently infiltrate tumors in substantial numbers. However, their precise functions in different cancer types remain incompletely understood, including in the brain microenvironment. We therefore investigated neutrophils in tumor tissue of glioma and brain metastasis patients, with matched peripheral blood, and herein describe the first in-depth analysis of neutrophil phenotypes and functions in these tissues. Orthogonal profiling strategies in humans and mice revealed that brain tumor-associated neutrophils (TANs) differ significantly from blood neutrophils and have a prolonged lifespan and immune-suppressive and pro-angiogenic capacity. TANs exhibit a distinct inflammatory signature, driven by a combination of soluble inflammatory mediators including tumor necrosis factor alpha (TNF-ɑ) and Ceruloplasmin, which is more pronounced in TANs from brain metastasis versus glioma. Myeloid cells, including tumor-associated macrophages, emerge at the core of this network of pro-inflammatory mediators, supporting the concept of a critical myeloid niche regulating overall immune suppression in human brain tumors.

2.
Nat Immunol ; 24(9): 1565-1578, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37580605

RESUMEN

Mucosal-associated invariant T (MAIT) cells are innate-like T cells that recognize microbial metabolites through a semi-invariant T cell receptor (TCR). Major questions remain regarding the extent of human MAIT cell functional and clonal diversity. To address these, we analyzed the single-cell transcriptome and TCR repertoire of blood and liver MAIT cells and developed functional RNA-sequencing, a method to integrate function and TCR clonotype at single-cell resolution. MAIT cell clonal diversity was comparable to conventional memory T cells, with private TCR repertoires shared across matched tissues. Baseline functional diversity was low and largely related to tissue site. MAIT cells showed stimulus-specific transcriptional responses in vitro, with cells positioned along gradients of activation. Clonal identity influenced resting and activated transcriptional profiles but intriguingly was not associated with the capacity to produce IL-17. Overall, MAIT cells show phenotypic and functional diversity according to tissue localization, stimulation environment and clonotype.


Asunto(s)
Células T Invariantes Asociadas a Mucosa , Humanos , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Células Clonales/metabolismo , Activación de Linfocitos/genética , Análisis de la Célula Individual
3.
Nature ; 601(7893): 415-421, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34987220

RESUMEN

Transcriptional and proteomic profiling of individual cells have revolutionized interpretation of biological phenomena by providing cellular landscapes of healthy and diseased tissues1,2. These approaches, however, do not describe dynamic scenarios in which cells continuously change their biochemical properties and downstream 'behavioural' outputs3-5. Here we used 4D live imaging to record tens to hundreds of morpho-kinetic parameters describing the dynamics of individual leukocytes at sites of active inflammation. By analysing more than 100,000 reconstructions of cell shapes and tracks over time, we obtained behavioural descriptors of individual cells and used these high-dimensional datasets to build behavioural landscapes. These landscapes recognized leukocyte identities in the inflamed skin and trachea, and uncovered a continuum of neutrophil states inside blood vessels, including a large, sessile state that was embraced by the underlying endothelium and associated with pathogenic inflammation. Behavioural screening in 24 mouse mutants identified the kinase Fgr as a driver of this pathogenic state, and interference with Fgr protected mice from inflammatory injury. Thus, behavioural landscapes report distinct properties of dynamic environments at high cellular resolution.


Asunto(s)
Inflamación , Leucocitos , Proteómica , Animales , Forma de la Célula , Endotelio/inmunología , Inflamación/inmunología , Leucocitos/inmunología , Ratones , Neutrófilos/inmunología , Proteínas Proto-Oncogénicas/inmunología , Familia-src Quinasas/inmunología
4.
Nature ; 610(7933): 693-698, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36224389

RESUMEN

Soils are the foundation of all terrestrial ecosystems1. However, unlike for plants and animals, a global assessment of hotspots for soil nature conservation is still lacking2. This hampers our ability to establish nature conservation priorities for the multiple dimensions that support the soil system: from soil biodiversity to ecosystem services. Here, to identify global hotspots for soil nature conservation, we performed a global field survey that includes observations of biodiversity (archaea, bacteria, fungi, protists and invertebrates) and functions (critical for six ecosystem services) in 615 composite samples of topsoil from a standardized survey in all continents. We found that each of the different ecological dimensions of soils-that is, species richness (alpha diversity, measured as amplicon sequence variants), community dissimilarity and ecosystem services-peaked in contrasting regions of the planet, and were associated with different environmental factors. Temperate ecosystems showed the highest species richness, whereas community dissimilarity peaked in the tropics, and colder high-latitudinal ecosystems were identified as hotspots of ecosystem services. These findings highlight the complexities that are involved in simultaneously protecting multiple ecological dimensions of soil. We further show that most of these hotspots are not adequately covered by protected areas (more than 70%), and are vulnerable in the context of several scenarios of global change. Our global estimation of priorities for soil nature conservation highlights the importance of accounting for the multidimensionality of soil biodiversity and ecosystem services to conserve soils for future generations.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Mapeo Geográfico , Microbiología del Suelo , Suelo , Animales , Conservación de los Recursos Naturales/métodos , Suelo/parasitología , Invertebrados , Archaea
5.
Proc Natl Acad Sci U S A ; 120(14): e2215428120, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36976767

RESUMEN

Understanding the mechanisms by which information and misinformation spread through groups of individual actors is essential to the prediction of phenomena ranging from coordinated group behaviors to misinformation epidemics. Transmission of information through groups depends on the rules that individuals use to transform the perceived actions of others into their own behaviors. Because it is often not possible to directly infer decision-making strategies in situ, most studies of behavioral spread assume that individuals make decisions by pooling or averaging the actions or behavioral states of neighbors. However, whether individuals may instead adopt more sophisticated strategies that exploit socially transmitted information, while remaining robust to misinformation, is unknown. Here, we study the relationship between individual decision-making and misinformation spread in groups of wild coral reef fish, where misinformation occurs in the form of false alarms that can spread contagiously through groups. Using automated visual field reconstruction of wild animals, we infer the precise sequences of socially transmitted visual stimuli perceived by individuals during decision-making. Our analysis reveals a feature of decision-making essential for controlling misinformation spread: dynamic adjustments in sensitivity to socially transmitted cues. This form of dynamic gain control can be achieved by a simple and biologically widespread decision-making circuit, and it renders individual behavior robust to natural fluctuations in misinformation exposure.


Asunto(s)
Animales Salvajes , Epidemias , Animales , Comunicación , Peces , Campos Visuales
6.
Crit Rev Biochem Mol Biol ; 58(1): 50-80, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-37158748

RESUMEN

Protein aggregation is implicated in multiple diseases, so-called proteinopathies, ranging from neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease (PD) to type 2 diabetes mellitus and sickle cell disease (SCD). The structure of the protein aggregates and the kinetics and mechanisms of aggregation have been the object of intense research over the years toward the development of therapeutic routes, including the design of aggregation inhibitors. Nonetheless, the rational design of drugs targeting aggregation inhibition remains a challenging endeavor because of multiple, disease-specific factors, including an incomplete understanding of protein function, the multitude of toxic and non-toxic protein aggregates, the lack of specific drug binding targets, discrepant action mechanisms of aggregation inhibitors, or a low selectivity, specificity, and/or drug potency, reflected in the high concentrations required for some inhibitors to be effective. Herein, we provide a perspective of this therapeutic route with emphasis on small molecules and peptide-based drugs in two diverse diseases, PD and SCD, aiming at establishing links among proposed aggregation inhibitors. The small and large length-scale regimes of the hydrophobic effect are discussed in light of the importance of hydrophobic interactions in proteinopathies. Some simulation results are reported on model peptides, illustrating the impact of hydrophobic and hydrophilic groups in water's hydrogen-bond network with an impact on drug binding. The seeming importance of aromatic rings and hydroxyl groups in protein-aggregation-inhibitor-drugs is emphasized along with the challenges associated with some inhibitors, limiting their development into effective therapeutic options, and questioning the potential of this therapeutic route.


Asunto(s)
Enfermedad de Alzheimer , Anemia de Células Falciformes , Diabetes Mellitus Tipo 2 , Enfermedad de Parkinson , Deficiencias en la Proteostasis , Humanos , Agregado de Proteínas , Enfermedad de Parkinson/tratamiento farmacológico , Diabetes Mellitus Tipo 2/complicaciones , Enfermedad de Alzheimer/metabolismo , Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/complicaciones , Deficiencias en la Proteostasis/complicaciones
7.
Circulation ; 150(9): 687-705, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-38881440

RESUMEN

BACKGROUND: Thromboembolic events, including myocardial infarction (MI) or stroke, caused by the rupture or erosion of unstable atherosclerotic plaques are the leading cause of death worldwide. Although most mouse models of atherosclerosis develop lesions in the aorta and carotid arteries, they do not develop advanced coronary artery lesions. Moreover, they do not undergo spontaneous plaque rupture with MI and stroke or do so at such a low frequency that they are not viable experimental models to study late-stage thrombotic events or to identify novel therapeutic approaches for treating atherosclerotic disease. This has stymied the development of more effective therapeutic approaches for reducing these events beyond what has been achieved with aggressive lipid lowering. Here, we describe a diet-inducible mouse model that develops widespread advanced atherosclerosis in coronary, brachiocephalic, and carotid arteries with plaque rupture, MI, and stroke. METHODS: We characterized a novel mouse model with a C-terminal mutation in the scavenger receptor class B, type 1 (SR-BI), combined with Ldlr knockout (designated SR-BI∆CT/∆CT/Ldlr-/-). Mice were fed Western diet (WD) for 26 weeks and analyzed for MI and stroke. Coronary, brachiocephalic, and carotid arteries were analyzed for atherosclerotic lesions and indices of plaque stability. To validate the utility of this model, SR-BI∆CT/∆CT/Ldlr-/- mice were treated with the drug candidate AZM198, which inhibits myeloperoxidase, an enzyme produced by activated neutrophils that predicts rupture of human atherosclerotic lesions. RESULTS: SR-BI∆CT/∆CT/Ldlr-/- mice show high (>80%) mortality rates after 26 weeks of WD feeding because of major adverse cardiovascular events, including spontaneous plaque rupture with MI and stroke. Moreover, WD-fed SR-BI∆CT/∆CT/Ldlr-/- mice displayed elevated circulating high-sensitivity cardiac troponin I and increased neutrophil extracellular trap formation within lesions compared with control mice. Treatment of WD-fed SR-BI∆CT/∆CT/Ldlr-/- mice with AZM198 showed remarkable benefits, including >90% improvement in survival and >60% decrease in the incidence of plaque rupture, MI, and stroke, in conjunction with decreased circulating high-sensitivity cardiac troponin I and reduced neutrophil extracellular trap formation within lesions. CONCLUSIONS: WD-fed SR-BI∆CT/∆CT/Ldlr-/- mice more closely replicate late-stage clinical events of advanced human atherosclerotic disease than previous models and can be used to identify and test potential new therapeutic agents to prevent major adverse cardiac events.


Asunto(s)
Infarto del Miocardio , Peroxidasa , Placa Aterosclerótica , Accidente Cerebrovascular , Animales , Masculino , Ratones , Dieta Occidental/efectos adversos , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/uso terapéutico , Inhibidores Enzimáticos/farmacología , Ratones Endogámicos C57BL , Ratones Noqueados , Infarto del Miocardio/patología , Infarto del Miocardio/tratamiento farmacológico , Peroxidasa/metabolismo , Placa Aterosclerótica/tratamiento farmacológico , Receptores de LDL/genética , Receptores de LDL/deficiencia , Rotura Espontánea , Receptores Depuradores de Clase B/genética , Receptores Depuradores de Clase B/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/prevención & control
8.
Genome Res ; 32(2): 242-257, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35042723

RESUMEN

Single-cell RNA sequencing (scRNA-seq) enables molecular characterization of complex biological tissues at high resolution. The requirement of single-cell extraction, however, makes it challenging for profiling tissues such as adipose tissue, for which collection of intact single adipocytes is complicated by their fragile nature. For such tissues, single-nucleus extraction is often much more efficient and therefore single-nucleus RNA sequencing (snRNA-seq) presents an alternative to scRNA-seq. However, nuclear transcripts represent only a fraction of the transcriptome in a single cell, with snRNA-seq marked with inherent transcript enrichment and detection biases. Therefore, snRNA-seq may be inadequate for mapping important transcriptional signatures in adipose tissue. In this study, we compare the transcriptomic landscape of single nuclei isolated from preadipocytes and mature adipocytes across human white and brown adipocyte lineages, with whole-cell transcriptome. We show that snRNA-seq is capable of identifying the broad cell types present in scRNA-seq at all states of adipogenesis. However, we also explore how and why the nuclear transcriptome is biased and limited, as well as how it can be advantageous. We robustly characterize the enrichment of nuclear-localized transcripts and adipogenic regulatory lncRNAs in snRNA-seq, while also providing a detailed understanding for the preferential detection of long genes upon using this technique. To remove such technical detection biases, we propose a normalization strategy for a more accurate comparison of nuclear and cellular data. Finally, we show successful integration of scRNA-seq and snRNA-seq data sets with existing bioinformatic tools. Overall, our results illustrate the applicability of snRNA-seq for the characterization of cellular diversity in the adipose tissue.


Asunto(s)
Adipocitos/citología , Linaje de la Célula , Perfilación de la Expresión Génica , RNA-Seq , Análisis de la Célula Individual , Sesgo , Perfilación de la Expresión Génica/métodos , Humanos , RNA-Seq/métodos , Análisis de la Célula Individual/métodos , Transcriptoma
9.
Arterioscler Thromb Vasc Biol ; 44(6): 1379-1392, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38695167

RESUMEN

BACKGROUND: Thromboembolic events secondary to rupture or erosion of advanced atherosclerotic lesions is the global leading cause of death. The most common and effective means to reduce these major adverse cardiovascular events, including myocardial infarction and stroke, is aggressive lipid lowering via a combination of drugs and dietary modifications. However, we know little regarding the effects of reducing dietary lipids on the composition and stability of advanced atherosclerotic lesions, the mechanisms that regulate these processes, and what therapeutic approaches might augment the benefits of lipid lowering. METHODS: Smooth muscle cell lineage-tracing Apoe-/- mice were fed a high-cholesterol Western diet for 18 weeks and then a zero-cholesterol standard laboratory diet for 12 weeks before treating them with an IL (interleukin)-1ß or control antibody for 8 weeks. We assessed lesion size and remodeling indices, as well as the cellular composition of aortic and brachiocephalic artery lesions, indices of plaque stability, overall plaque burden, and phenotypic transitions of smooth muscle cell and other lesion cells by smooth muscle cell lineage tracing combined with single-cell RNA sequencing, cytometry by time-of-flight, and immunostaining plus high-resolution confocal microscopic z-stack analysis. RESULTS: Lipid lowering by switching Apoe-/- mice from a Western diet to a standard laboratory diet reduced LDL cholesterol levels by 70% and resulted in multiple beneficial effects including reduced overall aortic plaque burden, as well as reduced intraplaque hemorrhage and necrotic core area. However, contrary to expectations, IL-1ß antibody treatment after diet-induced reductions in lipids resulted in multiple detrimental changes including increased plaque burden and brachiocephalic artery lesion size, as well as increasedintraplaque hemorrhage, necrotic core area, and senescence as compared with IgG control antibody-treated mice. Furthermore, IL-1ß antibody treatment upregulated neutrophil degranulation pathways but downregulated smooth muscle cell extracellular matrix pathways likely important for the protective fibrous cap. CONCLUSIONS: Taken together, IL-1ß appears to be required for the maintenance of standard laboratory diet-induced reductions in plaque burden and increases in multiple indices of plaque stability.


Asunto(s)
Aterosclerosis , Modelos Animales de Enfermedad , Interleucina-1beta , Ratones Noqueados para ApoE , Miocitos del Músculo Liso , Placa Aterosclerótica , Animales , Interleucina-1beta/metabolismo , Aterosclerosis/patología , Aterosclerosis/prevención & control , Aterosclerosis/metabolismo , Aterosclerosis/genética , Ratones , Miocitos del Músculo Liso/patología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Masculino , Dieta Occidental , Ratones Endogámicos C57BL , Aorta/patología , Aorta/metabolismo , Aorta/efectos de los fármacos , Enfermedades de la Aorta/patología , Enfermedades de la Aorta/prevención & control , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/metabolismo , Dieta Alta en Grasa , Músculo Liso Vascular/patología , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/efectos de los fármacos , Tronco Braquiocefálico/patología , Tronco Braquiocefálico/metabolismo , Tronco Braquiocefálico/efectos de los fármacos
10.
Physiol Genomics ; 56(2): 113-127, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37982169

RESUMEN

Endothelial cells (ECs) adapt to the unique needs of their resident tissue and metabolic perturbations, such as obesity. We sought to understand how obesity affects EC metabolic phenotypes, specifically mitochondrial gene expression. We investigated the mesenteric and adipose endothelium because these vascular beds have distinct roles in lipid homeostasis. Initially, we performed bulk RNA sequencing on ECs from mouse adipose and mesenteric vasculatures after a normal chow (NC) diet or high-fat diet (HFD) and found higher mitochondrial gene expression in adipose ECs compared with mesenteric ECs in both NC and HFD mice. Next, we performed single-cell RNA sequencing and categorized ECs as arterial, capillary, venous, or lymphatic. We found mitochondrial genes to be enriched in adipose compared with mesentery under NC conditions in artery and capillary ECs. After HFD, these genes were decreased in adipose ECs, becoming like mesenteric ECs. Transcription factor analysis revealed that peroxisome proliferator-activated receptor-γ (PPAR-γ) had high specificity in NC adipose artery and capillary ECs. These findings were recapitulated in single-nuclei RNA-sequencing data from human visceral adipose. The sum of these findings suggests that mesenteric and adipose arterial ECs metabolize lipids differently, and the transcriptional phenotype of the vascular beds converges in obesity due to downregulation of PPAR-γ in adipose artery and capillary ECs.NEW & NOTEWORTHY Using bulk and single-cell RNA sequencing on endothelial cells from adipose and mesentery, we found that an obesogenic diet induces a reduction in adipose endothelial oxidative phosphorylation gene expression, resulting in a phenotypic convergence of mesenteric and adipose endothelial cells. Furthermore, we found evidence that PPAR-γ drives this phenotypic shift. Mining of human data sets segregated based on body mass index supported these findings. These data point to novel mechanisms by which obesity induces endothelial dysfunction.


Asunto(s)
Endotelio Vascular , Genes Mitocondriales , Humanos , Ratones , Animales , Endotelio Vascular/metabolismo , Células Endoteliales/metabolismo , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Arterias , Obesidad/metabolismo , Dieta Alta en Grasa/efectos adversos , Tejido Adiposo/metabolismo
11.
Chembiochem ; : e202400018, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39159394

RESUMEN

Steroid hormones are essential for the biological processes of eukaryotic organisms. The steroid endocrine system of C. elegans, which includes dafachronic acids (DA) and the nuclear receptor ceDAF-12, provides a simple model for exploring the role of steroid hormone signaling pathways in animals. In this study, we show for the first time the feasibility of designing synthetic steroids that can modulate different physiological processes, such as development, reproduction and ageing, in relation to ceDAF-12. Our results not only confirm the conclusions derived from genetic studies linking these processes but also provide new chemical tools to selectively manipulate them, as we found that different compounds produce different phenotypic results. The structures of these compounds are much more diverse than those of endogenous hormones and analogues previously described by other researchers, allowing further development of the chemical modulation of the steroid endocrine system in C. elegans and related nematodes.

12.
Glob Chang Biol ; 30(5): e17295, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38804108

RESUMEN

Plant-soil biodiversity interactions are fundamental for the functioning of terrestrial ecosystems. Yet, the existence of a set of globally distributed topsoil microbial and small invertebrate organisms consistently associated with land plants (i.e., their consistent soil-borne microbiome), together with the environmental preferences and functional capabilities of these organisms, remains unknown. We conducted a standardized field survey under 150 species of land plants, including 58 species of bryophytes and 92 of vascular plants, across 124 locations from all continents. We found that, despite the immense biodiversity of soil organisms, the land plants evaluated only shared a small fraction (less than 1%) of all microbial and invertebrate taxa that were present across contrasting climatic and soil conditions and vegetation types. These consistent taxa were dominated by generalist decomposers and phagotrophs and their presence was positively correlated with the abundance of functional genes linked to mineralization. Finally, we showed that crossing environmental thresholds in aridity (aridity index of 0.65, i.e., the transition from mesic to dry ecosystems), soil pH (5.5; i.e., the transition from acidic to strongly acidic soils), and carbon (less than 2%, the lower limit of fertile soils) can result in drastic disruptions in the associations between land plants and soil organisms, with potential implications for the delivery of soil ecosystem processes under ongoing global environmental change.


Asunto(s)
Embryophyta , Microbiota , Microbiología del Suelo , Biodiversidad , Suelo/química
13.
Epilepsia ; 65(4): 1072-1091, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38411286

RESUMEN

OBJECTIVE: The intricate neuroanatomical structure of the cerebellum is of longstanding interest in epilepsy, but has been poorly characterized within the current corticocentric models of this disease. We quantified cross-sectional regional cerebellar lobule volumes using structural magnetic resonance imaging in 1602 adults with epilepsy and 1022 healthy controls across 22 sites from the global ENIGMA-Epilepsy working group. METHODS: A state-of-the-art deep learning-based approach was employed that parcellates the cerebellum into 28 neuroanatomical subregions. Linear mixed models compared total and regional cerebellar volume in (1) all epilepsies, (2) temporal lobe epilepsy with hippocampal sclerosis (TLE-HS), (3) nonlesional temporal lobe epilepsy, (4) genetic generalized epilepsy, and (5) extratemporal focal epilepsy (ETLE). Relationships were examined for cerebellar volume versus age at seizure onset, duration of epilepsy, phenytoin treatment, and cerebral cortical thickness. RESULTS: Across all epilepsies, reduced total cerebellar volume was observed (d = .42). Maximum volume loss was observed in the corpus medullare (dmax = .49) and posterior lobe gray matter regions, including bilateral lobules VIIB (dmax = .47), crus I/II (dmax = .39), VIIIA (dmax = .45), and VIIIB (dmax = .40). Earlier age at seizure onset ( η ρ max 2 = .05) and longer epilepsy duration ( η ρ max 2 = .06) correlated with reduced volume in these regions. Findings were most pronounced in TLE-HS and ETLE, with distinct neuroanatomical profiles observed in the posterior lobe. Phenytoin treatment was associated with reduced posterior lobe volume. Cerebellum volume correlated with cerebral cortical thinning more strongly in the epilepsy cohort than in controls. SIGNIFICANCE: We provide robust evidence of deep cerebellar and posterior lobe subregional gray matter volume loss in patients with chronic epilepsy. Volume loss was maximal for posterior subregions implicated in nonmotor functions, relative to motor regions of both the anterior and posterior lobe. Associations between cerebral and cerebellar changes, and variability of neuroanatomical profiles across epilepsy syndromes argue for more precise incorporation of cerebellar subregional damage into neurobiological models of epilepsy.


Asunto(s)
Epilepsia del Lóbulo Temporal , Síndromes Epilépticos , Adulto , Humanos , Epilepsia del Lóbulo Temporal/complicaciones , Fenitoína , Estudios Transversales , Síndromes Epilépticos/complicaciones , Cerebelo/diagnóstico por imagen , Cerebelo/patología , Convulsiones/complicaciones , Imagen por Resonancia Magnética/métodos , Atrofia/patología
14.
Photochem Photobiol Sci ; 23(5): 997-1010, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38693447

RESUMEN

Firefly luciferases emit yellow-green light and are pH-sensitive, changing the bioluminescence color to red in the presence of heavy metals, acidic pH and high temperatures. These pH and metal-sensitivities have been recently harnessed for intracellular pH indication and toxic metal biosensing. However, whereas the structure of the pH sensor and the metal binding site, which consists mainly of two salt bridges that close the active site (E311/R337 and H310/E354), has been identified, the specific role of residue H310 in pH and metal sensing is still under debate. The Amydetes vivianii firefly luciferase has one of the lowest pH sensitivities among the group of pH-sensitive firefly luciferases, displaying high bioluminescent activity and special spectral selectivity for cadmium and mercury, which makes it a promising analytical reagent. Using site-directed mutagenesis, we have investigated in detail the role of residue H310 on pH and metal sensitivity in this luciferase. Negatively charged residues at position 310 increase the pH sensitivity and metal sensitivity; H310G considerably increases the size of the cavity, severely impacting the activity, H310R closes the cavity, and H310F considerably decreases both pH and metal sensitivities. However, no substitution completely abolished pH and metal sensitivities. The results indicate that the presence of negatively charged and basic side chains at position 310 is important for pH sensitivity and metals coordination, but not essential, indicating that the remaining side chains of E311 and E354 may still coordinate some metals in this site. Furthermore, a metal binding site search predicted that H310 mutations decrease the affinity mainly for Zn, Ni and Hg but less for Cd, and revealed the possible existence of additional binding sites for Zn, Ni and Hg.


Asunto(s)
Luciérnagas , Histidina , Luciferasas de Luciérnaga , Mutagénesis Sitio-Dirigida , Concentración de Iones de Hidrógeno , Animales , Luciferasas de Luciérnaga/metabolismo , Luciferasas de Luciérnaga/química , Luciferasas de Luciérnaga/genética , Luciérnagas/enzimología , Histidina/química , Histidina/metabolismo , Color , Metales Pesados/química , Metales Pesados/metabolismo , Mercurio/química , Mercurio/metabolismo , Cadmio/química , Cadmio/metabolismo
15.
Photochem Photobiol Sci ; 23(9): 1757-1769, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39242437

RESUMEN

Porphyrazines (Pzs) are porphyrin derivatives that show potential application as photosensitizers for photodynamic therapy (PDT), but are still far less explored in the literature. In this work, we evaluate how the photophysics and phototoxicity of the octakis(trifluoromethylphenyl)porphyrazine (H2Pz) against tumor cells can be modulated by coordination with Mg(II), Zn(II), Cu(II) and Co(II) ions. Fluorescence and singlet oxygen quantum yields for the Pzs were measured in organic solvents and in soy phosphatidylcholine (PC) liposomes suspended in water. While H2Pz and the respective complexes with Cu(II) and Co(II) showed very low efficiency to fluoresce and to produce 1O2, the Mg(II) and Zn(II) complexes showed significantly higher quantum yields in organic solvents. The fluorescence of these two Pzs in the liposomes was sensitive to the fluidity of the membrane, showing potential use as viscosity markers. The cytotoxicity of the compounds was tested in HaCaT (normal) and A431 (tumor) cells using soy PC liposomes as drug carriers. Despite the low 1O2 quantum yields in water, the Mg(II) and Zn(II) complexes showed IC50 values against A431 cells in the nanomolar range when activated with low doses of red LED light. Their phototoxicity was ca. three times higher for the tumor cells compared to the normal ones, showing promising application as photosensitizers for PDT protocols. Considering that H2Pz and the respective Co(II) and Cu(II) complexes were practically non-phototoxic to the cells, we demonstrate the importance of the central metal ion in the modulation of the photodynamic activity of porphyrazines.


Asunto(s)
Liposomas , Fármacos Fotosensibilizantes , Porfirinas , Humanos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Porfirinas/química , Porfirinas/farmacología , Liposomas/química , Fotoquimioterapia , Oxígeno Singlete/metabolismo , Oxígeno Singlete/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Zinc/química , Zinc/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Iones/química
16.
J Chem Inf Model ; 64(15): 6115-6131, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39046235

RESUMEN

α-Synuclein (α-syn) is a 140 amino acid intrinsically disordered protein (IDP) and the primary component of cytotoxic oligomers implicated in the etiology of Parkinson's disease (PD). While IDPs lack a stable three-dimensional structure, they sample a heterogeneous ensemble of conformations that can, in principle, be assessed through molecular dynamics simulations. However, describing the structure and aggregation of large IDPs is challenging due to force field (FF) accuracy and sampling limitations. To cope with the latter, coarse-grained (CG) FFs emerge as a potential alternative at the expense of atomic detail loss. Whereas CG models can accurately describe the structure of the monomer, less is known about aggregation. The latter is key for assessing aggregation pathways and designing aggregation inhibitor drugs. Herein, we investigate the structure and dynamics of α-syn using different resolution CG (Martini3 and Sirah2) and all-atom (Amber99sb and Charmm36m) FFs to gain insight into the differences and resemblances between these models. The dependence of the magnitude of protein-water interactions and the putative need for enhanced sampling (replica exchange) methods in CG simulations are analyzed to distinguish between force field accuracy and sampling limitations. The stability of the CG models of an α-syn fibril was also investigated. Additionally, α-syn aggregation was studied through umbrella sampling for the CG models and CG/all-atom models for an 11-mer peptide (NACore) from an amyloidogenic domain of α-syn. Our results show that despite the α-syn structures of Martini3 and Sirah2 with enhanced protein-water interactions being similar, major differences exist concerning aggregation. The Martini3 fibril is not stable, and the binding free energy of α-syn and NACore is positive, opposite to Sirah2. Sirah2 peptides in a zwitterionic form, in turn, display termini interactions that are too strong, resulting in end-to-end orientation. Sirah2, with enhanced protein-water interactions and neutral termini, provides, however, a peptide aggregation free energy profile similar to that found with all-atom models. Overall, we find that Sirah2 with enhanced protein-water interactions is suitable for studying protein-protein and protein-drug aggregation.


Asunto(s)
Simulación de Dinámica Molecular , Agregado de Proteínas , alfa-Sinucleína , Humanos , alfa-Sinucleína/química , Conformación Proteica
17.
Phys Chem Chem Phys ; 26(26): 18244-18255, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38904333

RESUMEN

Natural deep eutectic solvents (NADESs) comprised of osmolytes are of interest as potential biomolecular (cryo)protectants. However, the way these solvents influence the structure and dynamics of biomolecules as well as the role of water remains poorly understood. We carried out principal component analysis of various secondary structure elements of ubiquitin in water and a betaine : glycerol : water (1 : 2 : ζ; ζ = 0, 1, 2, 5, 10, 20, 45) NADES, from molecular dynamics trajectories, to gain insight into the protein dynamics as it undergoes a transition from a highly viscous anhydrous to an aqueous environment. A crossover of the protein's essential dynamics at ζ ∼ 5, induced by solvent-shell coupled fluctuations, is observed, indicating that ubiquitin might (re)fold in the NADES upon water addition at ζ > ∼5. Further, in contrast to water, the anhydrous NADES preserves ubiquitin's essential modes at high temperatures explaining the protein's seemingly enhanced thermal stability.


Asunto(s)
Ubiquitina , Agua , Betaína/química , Glicerol/química , Simulación de Dinámica Molecular , Análisis de Componente Principal , Estructura Secundaria de Proteína , Solventes/química , Ubiquitina/química , Agua/química
18.
J Phys Chem A ; 128(28): 5586-5604, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38954748

RESUMEN

High-level electronic structure calculations were conducted to examine the bonding and spectroscopic properties of the UO0/± and UF0/± diatomic molecules. The low-lying Ω states were described by using multireference SO-CASPT2 calculations. The adiabatic electronic affinity (AEA), adiabatic ionization energy (IE), and bond dissociation energy (BDE) were calculated at the Feller-Peterson-Dixon (FPD) level. The ground state of UO is predicted to be 5I4, and that of UF is 4I9/2. The calculated AEAs of UO and UF are 1.123 and 0.453 eV, respectively, and the corresponding IEs are 5.976 and 6.278 eV. The BDE of UO (749.5 kJ/mol) is predicted to be considerably higher than that of UF (627.2 kJ/mol), and both are higher than those predicted for UB, UC, and UN. NBO calculations show strong ionic character for the ground states of UO and UF and bond orders that range from 2 to 3 and from 1 to 2, respectively. Comparisons of the calculated properties to those of the series comprising UB, UC, and UN diatomic molecules are given.

19.
Pharmacology ; 109(2): 86-97, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38368862

RESUMEN

BACKGROUND: Hepatic artery infusion chemotherapy (HAI) has been proposed as a valuable adjunct for multimodal therapy of primary and secondary liver malignancies. This review provides an overview of the currently available evidence of HAI, taking into account tumor response and long-term oncologic outcome. SUMMARY: In colorectal liver metastases (CRLM), HAI in combination with systemic therapy leads to high response rates (85-90%) and conversion to resectablity in primary unresectable disease in up to 50%. HAI in combination with systemic therapy in CRLM in the adjuvant setting shows promising long-term outcomes with up to 50% 10-year survival in a large, non-randomized single-center cohort. For hepatocellular carcinoma patients, response rates as high as 20-40% have been reported for HAI and long-term outcomes compare well to other therapies. Similarly, survival for patients with unresectable intrahepatic cholangiocarcinoma 3 years after treatment with HAI is reported as high as 34%, which compares well to trials of systemic therapy where 3-year survival is usually below 5%. However, evidence is mainly limited by highly selected, heterogenous patient groups, and outdated chemotherapy regimens. The largest body of evidence stems from small, often non-randomized cohorts, predominantly from highly specialized single centers. KEY MESSAGE: In well-selected patients with primary and secondary liver malignancies, HAI might improve response rates and, possibly, long-term survival. Results of ongoing randomized trials will show whether a wider adoption of HAI is justified, particularly to increase rates of resectability in advanced malignant diseases confined to the liver.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Arteria Hepática/patología , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Hepáticas/tratamiento farmacológico , Fluorouracilo , Resultado del Tratamiento
20.
J Drugs Dermatol ; 23(2): 67-73, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38306122

RESUMEN

There is contrasting evidence regarding the efficacy and safety of JAK (Janus kinase) inhibitors in the treatment of psoriasis. This systematic review and meta-analysis assessed deucravacitinib, an oral, selective, allosteric tyrosine kinase 2 inhibitor, as the therapy of choice for moderate-to-severe psoriasis. PubMed, Embase, and Cochrane databases were searched for randomized controlled trials, including patients with moderate-to-severe psoriasis. Outcomes of interest were serious adverse events (SAEs), the severity of illness, as measured by the validated questionnaires: Psoriasis Area and Severity Index (PASI) and scalp-specific Physician's Global Assessment (ss-PGA); and quality of life, measured by the Dermatology Life Quality Index (DLQI). Four studies with 1663 patients were included in the meta-analysis, of whom 1123 (67.5%) were treated with deucravacitinib during a 12-to-16-week follow-up. The mean age was 45.4 ± 13.3 years, and 70.2% were male. Two-thirds had a history of scalp psoriasis. Achievement of PASI 75 was significantly higher in the deucravacitinib group, as compared with placebo (RR 5.7; 95% CI 4.32-7.53; P<0.001). Similarly, ss-PGA 0/1 (RR 3.86; 95%CI 3.02-4.94; P<0.001) and DLQI 0/1 (RR 3.89; 2.89-5.22; P<0.001) were also significantly more frequent in the deucravacitinib group. The incidence of SAEs was similar between groups. These findings suggest that patients with moderate-to-severe psoriasis treated with deucravacitinib for 12 to 16 weeks had significantly decreased severity of illness and improved quality of life, without a concerning increase in the incidence of SAEs. J Drugs Dermatol. 2024;23(2):67-73.  doi:10.36849/JDD.7539.


Asunto(s)
Compuestos Heterocíclicos , Psoriasis , Humanos , Psoriasis/diagnóstico , Psoriasis/tratamiento farmacológico , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
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