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1.
Cell ; 187(16): 4150-4175, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39121846

RESUMEN

Cellular senescence is a cell fate triggered in response to stress and is characterized by stable cell-cycle arrest and a hypersecretory state. It has diverse biological roles, ranging from tissue repair to chronic disease. The development of new tools to study senescence in vivo has paved the way for uncovering its physiological and pathological roles and testing senescent cells as a therapeutic target. However, the lack of specific and broadly applicable markers makes it difficult to identify and characterize senescent cells in tissues and living organisms. To address this, we provide practical guidelines called "minimum information for cellular senescence experimentation in vivo" (MICSE). It presents an overview of senescence markers in rodent tissues, transgenic models, non-mammalian systems, human tissues, and tumors and their use in the identification and specification of senescent cells. These guidelines provide a uniform, state-of-the-art, and accessible toolset to improve our understanding of cellular senescence in vivo.


Asunto(s)
Senescencia Celular , Humanos , Animales , Biomarcadores/metabolismo , Guías como Asunto , Neoplasias/patología
3.
Nat Aging ; 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39210150

RESUMEN

Inhibition of S6 kinase 1 (S6K1) extends lifespan and improves healthspan in mice, but the underlying mechanisms are unclear. Cellular senescence is a stable growth arrest accompanied by an inflammatory senescence-associated secretory phenotype (SASP). Cellular senescence and SASP-mediated chronic inflammation contribute to age-related pathology, but the specific role of S6K1 has not been determined. Here we show that S6K1 deletion does not reduce senescence but ameliorates inflammation in aged mouse livers. Using human and mouse models of senescence, we demonstrate that reduced inflammation is a liver-intrinsic effect associated with S6K deletion. Specifically, we show that S6K1 deletion results in reduced IRF3 activation; impaired production of cytokines, such as IL1ß; and reduced immune infiltration. Using either liver-specific or myeloid-specific S6K knockout mice, we also demonstrate that reduced immune infiltration and clearance of senescent cells is a hepatocyte-intrinsic phenomenon. Overall, deletion of S6K reduces inflammation in the liver, suggesting that suppression of the inflammatory SASP by loss of S6K could underlie the beneficial effects of inhibiting this pathway on healthspan and lifespan.

5.
Nature ; 632(8023): 157-165, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39020175

RESUMEN

For healthspan and lifespan, ERK, AMPK and mTORC1 represent critical pathways and inflammation is a centrally important hallmark1-7. Here we examined whether IL-11, a pro-inflammatory cytokine of the IL-6 family, has a negative effect on age-associated disease and lifespan. As mice age, IL-11 is upregulated across cell types and tissues to regulate an ERK-AMPK-mTORC1 axis to modulate cellular, tissue- and organismal-level ageing pathologies. Deletion of Il11 or Il11ra1 protects against metabolic decline, multi-morbidity and frailty in old age. Administration of anti-IL-11 to 75-week-old mice for 25 weeks improves metabolism and muscle function, and reduces ageing biomarkers and frailty across sexes. In lifespan studies, genetic deletion of Il11 extended the lives of mice of both sexes, by 24.9% on average. Treatment with anti-IL-11 from 75 weeks of age until death extends the median lifespan of male mice by 22.5% and of female mice by 25%. Together, these results demonstrate a role for the pro-inflammatory factor IL-11 in mammalian healthspan and lifespan. We suggest that anti-IL-11 therapy, which is currently in early-stage clinical trials for fibrotic lung disease, may provide a translational opportunity to determine the effects of IL-11 inhibition on ageing pathologies in older people.


Asunto(s)
Envejecimiento , Interleucina-11 , Longevidad , Transducción de Señal , Animales , Femenino , Masculino , Ratones , Envejecimiento/efectos de los fármacos , Envejecimiento/genética , Envejecimiento/metabolismo , Envejecimiento/patología , Proteínas Quinasas Activadas por AMP/metabolismo , Fragilidad/genética , Fragilidad/metabolismo , Fragilidad/prevención & control , Inflamación/metabolismo , Inflamación/tratamiento farmacológico , Interleucina-11/antagonistas & inhibidores , Interleucina-11/deficiencia , Interleucina-11/genética , Interleucina-11/metabolismo , Subunidad alfa del Receptor de Interleucina-11/metabolismo , Subunidad alfa del Receptor de Interleucina-11/deficiencia , Longevidad/efectos de los fármacos , Longevidad/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Humanos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología
6.
Artículo en Inglés | MEDLINE | ID: mdl-38889348
8.
Nat Prod Res ; : 1-7, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38414225

RESUMEN

This study explores the phytochemical composition of leaf extracts from Handroanthus impetiginosus (Mart.) Mattos and Luehea divaricata Mart., used in a contraceptive decoction by Mbya-Guarani women. The phytocompounds were identified by gas chro-matography-mass spectrometry, while Fourier-transform infrared spectroscopy, multi-elemental, and thermal analyses were used to characterise plant biomass. Notably, no phytoconstituent supporting the efficacy of these extracts as female contraceptives was found, except for a small amount (0.3%) of sitosterol. Conversely, L. divaricata leaves contained compounds like 1,3-dihydroxyacetone dimer, N-methyl-N-nitroso-2-propanamine, 2-methoxy-N-(2-methoxyethyl)-N-methyl-ethanamine, and 1,3,5-triazine-2,4,6-triamine, potentially exerting cytotoxic, genotoxic, and toxicogenomic effects. Due to the absence of scientific support for the claimed contraceptive efficacy and the presence of safety concerns, we propose an alternative valorisation pathway centred on the presence of phytochemicals exhibiting antimicrobial activity. This proposition is substantiated by their considerable in vitro efficacy against Botrytis cinerea.

10.
Nat Commun ; 15(1): 1041, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38310113

RESUMEN

Cellular senescence is a stress response with broad pathophysiological implications. Senotherapies can induce senescence to treat cancer or eliminate senescent cells to ameliorate ageing and age-related pathologies. However, the success of senotherapies is limited by the lack of reliable ways to identify senescence. Here, we use nuclear morphology features of senescent cells to devise machine-learning classifiers that accurately predict senescence induced by diverse stressors in different cell types and tissues. As a proof-of-principle, we use these senescence classifiers to characterise senolytics and to screen for drugs that selectively induce senescence in cancer cells but not normal cells. Moreover, a tissue senescence score served to assess the efficacy of senolytic drugs and identified senescence in mouse models of liver cancer initiation, ageing, and fibrosis, and in patients with fatty liver disease. Thus, senescence classifiers can help to detect pathophysiological senescence and to discover and validate potential senotherapies.


Asunto(s)
Envejecimiento , Senescencia Celular , Animales , Ratones , Humanos , Envejecimiento/fisiología , Senescencia Celular/fisiología , Fibrosis
11.
Int J Mol Sci ; 25(2)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38256176

RESUMEN

Advancements in polymer science and nanotechnology hold significant potential for addressing the increasing demands of food security, by enhancing the shelf life, barrier properties, and nutritional quality of harvested fruits and vegetables. In this context, biopolymer-based delivery systems present themselves as a promising strategy for encapsulating bioactive compounds, improving their absorption, stability, and functionality. This study provides an exploration of the synthesis, characterization, and postharvest protection applications of nanocarriers formed through the complexation of chitosan oligomers, carboxymethylcellulose, and alginate in a 2:2:1 molar ratio. This complexation process was facilitated by methacrylic anhydride and sodium tripolyphosphate as cross-linking agents. Characterization techniques employed include transmission electron microscopy, energy-dispersive X-ray spectroscopy, infrared spectroscopy, thermal analysis, and X-ray powder diffraction. The resulting hollow nanospheres, characterized by a monodisperse distribution and a mean diameter of 114 nm, exhibited efficient encapsulation of carvacrol, with a loading capacity of approximately 20%. Their suitability for phytopathogen control was assessed in vitro against three phytopathogens-Botrytis cinerea, Penicillium expansum, and Colletotrichum coccodes-revealing minimum inhibitory concentrations ranging from 23.3 to 31.3 µg·mL-1. This indicates a higher activity compared to non-encapsulated conventional fungicides. In ex situ tests for tomato (cv. 'Daniela') protection, higher doses (50-100 µg·mL-1, depending on the pathogen) were necessary to achieve high protection. Nevertheless, these doses remained practical for real-world applicability. The advantages of safety, coupled with the potential for a multi-target mode of action, further enhance the appeal of these nanocarriers.


Asunto(s)
Quitosano , Cimenos , Solanum lycopersicum , Carboximetilcelulosa de Sodio , Alginatos
12.
Sci Rep ; 14(1): 2131, 2024 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-38267495

RESUMEN

Mosquitoes are primary vectors of pathogens impacting humans, wildlife, and livestock. Among them, the Asian tiger mosquito, Aedes albopictus, stands out as an invasive species with a global distribution, having established populations on every continent except Antarctica. Recent findings incriminate Ae. albopictus in the local transmission of several pathogens causing human diseases, including dengue, chikungunya, and Zika viruses and worm parasites as Dirofilaria. In Spain, the establishment of Ae. albopictus occurred in 2004 and it rapidly expanded, currently reaching southern provinces and creating novel epidemiological scenarios in recently invaded areas. In this study, we conducted captures of Ae. albopictus from May to November 2022 in two provinces, Granada and Malaga, situated near the current edge of the species' expanding range in Spain. The objective was to identify the primary factors influencing their captures in these regions. Mosquitoes were captured using BG-Sentinel traps baited with CO2 and BG-Lure, and miniature CDC-UV traps in five different localities. Our findings underscore the influence of both extrinsic factors, such as locality, and intrinsic factors, including mosquito sex, on the abundance of captured Ae. albopictus. A higher abundance of Ae. albopictus was observed in the Malaga province compared to localities in the Granada province. Furthermore, similar numbers of Ae. albopictus mosquitoes were captured in more urbanized areas of Granada, while the lowest counts were recorded in the less urbanized area. These results were compared to captures of another common species in the area, specifically Culex pipiens. Overall, these results represent the first monitoring of invasive Ae. albopictus in the area and are discussed in the light of the potential importance of the species as a nuisance for humans and vectors of pathogens of public health relevance.


Asunto(s)
Aedes , Culex , Infección por el Virus Zika , Virus Zika , Humanos , Animales , Estaciones del Año , España , Mosquitos Vectores , Ligando de CD40 , Infección por el Virus Zika/epidemiología
13.
Protein Sci ; 33(1): e4835, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37984447

RESUMEN

Pulmonary surfactant (PS) is a lipid-protein complex that forms films reducing surface tension at the alveolar air-liquid interface. Surfactant protein C (SP-C) plays a key role in rearranging the lipids at the PS surface layers during breathing. The N-terminal segment of SP-C, a lipopeptide of 35 amino acids, contains two palmitoylated cysteines, which affect the stability and structure of the molecule. The C-terminal region comprises a transmembrane α-helix that contains a ALLMG motif, supposedly analogous to a well-studied dimerization motif in glycophorin A. Previous studies have demonstrated the potential interaction between SP-C molecules using approaches such as Bimolecular Complementation assays or computational simulations. In this work, the oligomerization state of SP-C in membrane systems has been studied using fluorescence spectroscopy techniques. We have performed self-quenching and FRET assays to analyze dimerization of native palmitoylated SP-C and a non-palmitoylated recombinant version of SP-C (rSP-C) using fluorescently labeled versions of either protein reconstituted in different lipid systems mimicking pulmonary surfactant environments. Our results reveal that doubly palmitoylated native SP-C remains primarily monomeric. In contrast, non-palmitoylated recombinant SP-C exhibits dimerization, potentiated at high concentrations, especially in membranes with lipid phase separation. Therefore, palmitoylation could play a crucial role in stabilizing the monomeric α-helical conformation of SP-C. Depalmitoylation, high protein densities as a consequence of membrane compartmentalization, and other factors may all lead to the formation of protein dimers and higher-order oligomers, which could have functional implications under certain pathological conditions and contribute to membrane transformations associated with surfactant metabolism and alveolar homeostasis.


Asunto(s)
Proteína C Asociada a Surfactante Pulmonar , Surfactantes Pulmonares , Proteína C Asociada a Surfactante Pulmonar/química , Proteína C Asociada a Surfactante Pulmonar/metabolismo , Surfactantes Pulmonares/química , Surfactantes Pulmonares/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Lípidos/química , Tensoactivos
14.
Nat Cell Biol ; 25(12): 1804-1820, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38012402

RESUMEN

Drugs that selectively kill senescent cells (senolytics) improve the outcomes of cancer, fibrosis and age-related diseases. Despite their potential, our knowledge of the molecular pathways that affect the survival of senescent cells is limited. To discover senolytic targets, we performed RNAi screens and identified coatomer complex I (COPI) vesicle formation as a liability of senescent cells. Genetic or pharmacological inhibition of COPI results in Golgi dispersal, dysfunctional autophagy, and unfolded protein response-dependent apoptosis of senescent cells, and knockdown of COPI subunits improves the outcomes of cancer and fibrosis in mouse models. Drugs targeting COPI have poor pharmacological properties, but we find that N-myristoyltransferase inhibitors (NMTi) phenocopy COPI inhibition and are potent senolytics. NMTi selectively eliminated senescent cells and improved outcomes in models of cancer and non-alcoholic steatohepatitis. Our results suggest that senescent cells rely on a hyperactive secretory apparatus and that inhibiting trafficking kills senescent cells with the potential to treat various senescence-associated diseases.


Asunto(s)
Neoplasias , Senoterapéuticos , Ratones , Animales , Aparato de Golgi/metabolismo , Senescencia Celular , Neoplasias/metabolismo , Fibrosis
15.
PLoS One ; 18(11): e0293678, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37992030

RESUMEN

The fecal immunochemical test (FIT) is the most widely used test for colorectal cancer (CRC) screening. RAID-CRC Screen is a new non-invasive test based on fecal bacterial markers, developed to complement FIT by increasing its specificity. The test was previously clinically evaluated in FIT-positive patients (>20 µg of hemoglobin/g of feces, "FIT20"), in which it reduced the proportion of false positive results by 16.3% while maintaining most of FIT20's sensitivity. The aim of this study was to compare the sensitivity and specificity of a CRC screening program using RAID-CRC Screen in addition to FIT20 as a triage test in a European screening population undergoing screening colonoscopy with a CRC screening program with FIT20 alone in the same cohort. A cohort of 2481 subjects aged > 55 years from the German screening colonoscopy program was included. The colonoscopy findings were used as the gold standard in calculating the diagnostic capacity of the tests and included 15 CRC and 257 advanced neoplasia cases. RAID-CRC Screen added to FIT20 provided the same sensitivity as FIT20 alone (66.7%) in detecting CRC and a significantly higher specificity (97.0% vs. 96.1%, p<0.0001). The positive predictive value was 11.9% when using RAID-CRC Screen and 9.5% with FIT20 alone, and the negative predictive value was 99.8% in the two scenarios. For advanced neoplasia detection, the use of RAID-CRC Screen yielded significantly lower sensitivity than with FIT20 alone (17.5% vs. 21.8%, p = 0.0009), and the overall specificity was significantly higher when using RAID-CRC Screen compared with FIT20 alone (98.2% vs. 97.8%, p = 0.0039). Our findings confirm the results obtained in previous clinical studies in a CRC screening setting, showing the potential of RAID-CRC Screen to increase the overall specificity of FIT-based screening.


Asunto(s)
Neoplasias Colorrectales , Detección Precoz del Cáncer , Humanos , Detección Precoz del Cáncer/métodos , Neoplasias Colorrectales/diagnóstico , Sensibilidad y Especificidad , Tamizaje Masivo/métodos , Colonoscopía , Sangre Oculta , Heces
17.
Heliyon ; 9(9): e19978, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809756

RESUMEN

Recycled aggregate (RA) made from waste concrete is an environmentally friendly alternative to natural aggregate (NA) for concrete manufacturing. However, compared to NA concrete, concrete produced with recycled aggregates has poor characteristics. Supplementary cementitious materials (SCMs) can be used to enhance the poor properties of recycled aggregate concrete (RAC). Silica fume and fly ash are commonly used SCMs in the World, but their high usage led to a shortage of silica fume and fly ash. Still, the deficiency of these materials in large parts of the world is a challenge that requires exploring alternative feedstock materials for the construction industry in the coming years. Wheat straw ash (WSA) is an agricultural waste product that could be used as an alternative SCM due to its pozzolanic behavior to enhance the properties of RAC. In addition, concrete is brittle and needs reinforcement, for which polypropylene fibers (PPFs) can be used. The current research examines the mechanical characteristics of fiber-reinforced RAC, including compressive strength, splitting tensile strength, and ductility performance. Durability indicators, such as chloride diffusion, chloride penetration, acid resistance, and water absorption test, were also assessed. The results showed that concrete samples with 10% WSA, 50% RA and 1.5% PPFs had the highest compressive and splitting tensile strength, 60.2 MPa and 7.25 MPa, respectively, representing increases of 24.75% and 30.65%, as compared to plain samples at 56 days. In these samples, water absorption was reduced by 13% due to the finer WSA particles resulting in the lowest reduction in strength and mass recorded when exposing concrete samples to acidic media. The statistical analysis also validated that irrespective of WSA and PPFs, the concrete with 0% RA had the highest performance in strength and durability behavior. The study showed that WSA and PPFs might be employed in tandem to offset the poor behavior of RA, enhance the bond between fibers and concrete, and improve the mechanical strength and durability performance of RAC, thus demonstrating its suitability as a sustainable and economical construction material.

18.
Nat Cell Biol ; 25(11): 1554-1556, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37884646
19.
Nature ; 623(7989): 1053-1061, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37844613

RESUMEN

Inflammation is a hallmark of cancer1. In patients with cancer, peripheral blood myeloid expansion, indicated by a high neutrophil-to-lymphocyte ratio, associates with shorter survival and treatment resistance across malignancies and therapeutic modalities2-5. Whether myeloid inflammation drives progression of prostate cancer in humans remain unclear. Here we show that inhibition of myeloid chemotaxis can reduce tumour-elicited myeloid inflammation and reverse therapy resistance in a subset of patients with metastatic castration-resistant prostate cancer (CRPC). We show that a higher blood neutrophil-to-lymphocyte ratio reflects tumour myeloid infiltration and tumour expression of senescence-associated mRNA species, including those that encode myeloid-chemoattracting CXCR2 ligands. To determine whether myeloid cells fuel resistance to androgen receptor signalling inhibitors, and whether inhibiting CXCR2 to block myeloid chemotaxis reverses this, we conducted an investigator-initiated, proof-of-concept clinical trial of a CXCR2 inhibitor (AZD5069) plus enzalutamide in patients with metastatic CRPC that is resistant to androgen receptor signalling inhibitors. This combination was well tolerated without dose-limiting toxicity and it decreased circulating neutrophil levels, reduced intratumour CD11b+HLA-DRloCD15+CD14- myeloid cell infiltration and imparted durable clinical benefit with biochemical and radiological responses in a subset of patients with metastatic CRPC. This study provides clinical evidence that senescence-associated myeloid inflammation can fuel metastatic CRPC progression and resistance to androgen receptor blockade. Targeting myeloid chemotaxis merits broader evaluation in other cancers.


Asunto(s)
Antagonistas de Receptores Androgénicos , Antineoplásicos , Quimiotaxis , Resistencia a Antineoplásicos , Células Mieloides , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Quimiotaxis/efectos de los fármacos , Progresión de la Enfermedad , Inflamación/tratamiento farmacológico , Inflamación/patología , Antígeno Lewis X/metabolismo , Células Mieloides/efectos de los fármacos , Células Mieloides/patología , Metástasis de la Neoplasia , Próstata/efectos de los fármacos , Próstata/metabolismo , Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Receptores Androgénicos/metabolismo , Antagonistas de Receptores Androgénicos/farmacología , Antagonistas de Receptores Androgénicos/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico
20.
Cell ; 186(23): 5135-5150.e28, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37865090

RESUMEN

Mycobacterium tuberculosis (Mtb) cultured axenically without detergent forms biofilm-like cords, a clinical identifier of virulence. In lung-on-chip (LoC) and mouse models, cords in alveolar cells contribute to suppression of innate immune signaling via nuclear compression. Thereafter, extracellular cords cause contact-dependent phagocyte death but grow intercellularly between epithelial cells. The absence of these mechanopathological mechanisms explains the greater proportion of alveolar lesions with increased immune infiltration and dissemination defects in cording-deficient Mtb infections. Compression of Mtb lipid monolayers induces a phase transition that enables mechanical energy storage. Agent-based simulations demonstrate that the increased energy storage capacity is sufficient for the formation of cords that maintain structural integrity despite mechanical perturbation. Bacteria in cords remain translationally active despite antibiotic exposure and regrow rapidly upon cessation of treatment. This study provides a conceptual framework for the biophysics and function in tuberculosis infection and therapy of cord architectures independent of mechanisms ascribed to single bacteria.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Animales , Ratones , Biopelículas , Pulmón/microbiología , Pulmón/patología , Mycobacterium tuberculosis/fisiología , Tuberculosis/microbiología , Tuberculosis/patología , Virulencia , Fenómenos Biomecánicos
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