Assessment of Genotoxicity Induced by Subchronic Exposure to Graphene in HaCaT Human Skin Cell Line

The applications of graphene-based materials (GBMs) and even their processing involve prolonged contact with cellular barriers such as human skin. Even though the potential cytotoxicity of graphene has been studied in recent years, the impact of long-term graphene exposure has rarely been explored. We tested in the HaCaT epithelial cells, in vitro, the effect of subchronic treatments with subletal doses of four different, well-characterized GBMs, two commercial graphene oxides (GO) and two few-layer graphenes (FLG). Cells were exposed weekly to low doses of the GBMs for 14 days, 30 days, 3 months, and 6 months. GBMs-cells uptake was assessed by confocal microscopy. Cell death and cell cycle were determined by fluorescence microscopy and cytometry, respectively. DNA damage was measured by comet assay and g-H2AX staining, followed by determination of p-p53 and p-ATR by immunolabeling. Subchronic exposure to different GBMs at non-cytotoxic doses has potential genotoxic effects on HaCaT epithelial cells, that can be recovered depending on the GBM and exposure time. Specifically, GO-induced genotoxicity can be detected after 14 and 30 days from treatment. At this time, FLG appears less genotoxic than GO, and cells can recover more easily when genotoxic pressure disappears after some days removal of the GBM. Long-term exposure, 3 and 6 months, to different GBMs induces permanent, non-reversible, genotoxic damage that is comparable than the exerted by arsenite. This should be considered for the production and future applications of GBMs in scenarios where low concentrations of the material interact chronically with epithelial barriers

CoQ10 reduces glioblastoma growth and infiltration through proteome remodeling and inhibition of angiogenesis and inflammation

Purpose: Most monotherapies available against glioblastoma multiforme (GBM) target individual hallmarks of this aggressive brain tumor with minimal success. In this article, we propose a therapeutic strategy using coenzyme Q10 (CoQ10) as a pleiotropic factor that crosses the blood-brain barrier and accumulates in cell membranes acting as an antioxidant, and in mitochondrial membranes as a regulator of cell bioenergetics and gene expression. Methods: Xenografts of U251 cells in nu/nu mice were used to assay tumor growth, hypoxia, angiogenesis, and inflammation. An orthotopic model was used to explore microglial infiltration, tumor growth, and invasion into the brain parenchyma. Cell proliferation, migration, invasion, proteome remodeling, and secretome were assayed in vitro. Conditioned media were used to assay angiogenesis, monocyte chemoattraction, and differentiation into macrophages in vitro. Results: CoQ10 treatment decreased tumor volume in xenografts and orthotopic models, although its effect on tumor cell proliferation was not direct. Tumors from mice treated with CoQ10 were less hypoxic and vascularized, having less infiltration from inflammatory cells. Treatment-induced downregulation of HIF-1α and NF-kB led to a complete remodeling of the tumor cells proteome and secretome, impacting angiogenesis, monocyte infiltration, and their differentiation into macrophages. Besides, tumor cell migration and invasion were drastically restricted by mechanisms involving modulation of the actin cytoskeleton and downregulation of matrix metalloproteases (MMPs). Conclusions: CoQ10 has a pleiotropic effect on GBM growth, targeting several hallmarks simultaneously. Thus, its integration into current treatments of this fatal disease should be considered. Keywords: Angiogenesis; Coenzyme Q10; Glioblastoma; Inflammation; Invasion.Propósito: La mayoría de las monoterapias disponibles contra el glioblastoma multiforme (GBM) se dirigen a las características individuales de este tumor cerebral agresivo con un éxito mínimo. En este artículo proponemos una estrategia terapéutica utilizando la coenzima Q 10 (CoQ 10 ) como factor pleiotrópico que atraviesa la barrera hematoencefálica y se acumula en las membranas celulares actuando como antioxidante, y en las membranas mitocondriales como regulador de la bioenergética celular y gen expresión. Métodos: Se utilizaron xenoinjertos de células U251 en ratones nu/nu para analizar el crecimiento tumoral, la hipoxia, la angiogénesis y la inflamación. Se utilizó un modelo ortotópico para explorar la infiltración microglial, el crecimiento tumoral y la invasión del parénquima cerebral. Se ensayaron in vitro la proliferación celular, la migración, la invasión, la remodelación del proteoma y el secretoma. Se usaron medios acondicionados para analizar la angiogénesis, la quimioatracción de monocitos y la diferenciación en macrófagos in vitro. Resultados: el tratamiento con CoQ 10 disminuyó el volumen tumoral en xenoinjertos y modelos ortotópicos, aunque su efecto sobre la proliferación de células tumorales no fue directo. Los tumores de ratones tratados con CoQ 10 eran menos hipóxicos y vascularizados, con menos infiltración de células inflamatorias. La regulación a la baja inducida por el tratamiento de HIF-1α y NF-kB condujo a una remodelación completa del proteoma y el secretoma de las células tumorales, lo que impactó en la angiogénesis, la infiltración de monocitos y su diferenciación en macrófagos. Además, la migración e invasión de células tumorales se vieron drásticamente restringidas por mecanismos que involucran la modulación del citoesqueleto de actina y la regulación a la baja de las metaloproteasas de matriz (MMP). Conclusiones: CoQ 10 tiene un efecto pleiotrópico en el crecimiento de GBM, apuntando a varios sellos simultáneamente. Por lo tanto, se debe considerar su integración en los tratamientos actuales de esta enfermedad mortal

Spatial and Temporal Protein Modules Signatures Associated with Alzheimer Disease in 3xTg-AD Mice Are Restored by Early Ubiquinol Supplementation

Despite its robust proteopathic nature, the spatiotemporal signature of disrupted protein modules in sporadic Alzheimer's disease (AD) brains remains poorly understood. This considered oxidative stress contributes to AD progression and early intervention with coenzyme Q10 or its reduced form, ubiquinol, delays the progression of the disease. Using MALDI-MSI and functional bioinformatic analysis, we have developed a protocol to express how deregulated protein modules arise from hippocampus and cortex in the AD mice model 3xTG-AD in an age-dependent manner. This strategy allowed us to identify which modules can be efficiently restored to a non-pathological condition by early intervention with ubiquinol. Indeed, an early deregulation of proteostasis-related protein modules, oxidative stress and metabolism has been observed in the hippocampus of 6-month mice (early AD) and the mirrored in cortical regions of 12-month mice (middle/late AD). This observation has been validated by IHC using mouse and human brain sections, suggesting that these protein modules are also affected in humans. The emergence of disrupted protein modules with AD signature can be prevented by early dietary intervention with ubiquinol in the 3xTG-AD mice model.A pesar de su robusta naturaleza proteopática, la firma espaciotemporal de los módulos de proteínas interrumpidos en los cerebros de la enfermedad de Alzheimer (EA) esporádica sigue siendo poco conocida. Este considerado estrés oxidativo contribuye a la progresión de la EA y la intervención precoz con coenzima Q10 o su forma reducida, el ubiquinol, retrasa la progresión de la enfermedad. Usando MALDI-MSI y análisis bioinformático funcional, hemos desarrollado un protocolo para expresar cómo surgen módulos de proteína desregulados del hipocampo y la corteza en el modelo de ratones AD 3xTG-AD de una manera dependiente de la edad. Esta estrategia nos permitió identificar qué módulos se pueden restaurar de manera eficiente a una condición no patológica mediante una intervención temprana con ubiquinol. De hecho, una desregulación temprana de los módulos proteicos relacionados con la proteostasis, Se ha observado estrés oxidativo y metabolismo en el hipocampo de ratones de 6 meses (EA temprana) y se refleja en regiones corticales de ratones de 12 meses (EA media/tardía). Esta observación ha sido validada por IHC utilizando secciones de cerebro humano y de ratón, lo que sugiere que estos módulos de proteína también se ven afectados en humanos. La aparición de módulos de proteínas interrumpidos con la firma AD puede prevenirse mediante una intervención dietética temprana con ubiquinol en el modelo de ratones 3xTG-AD

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality