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Cell-cell communication via ligand-receptor signaling is a fundamental feature of complex organs. Despite this, the global landscape of intercellular signaling in mammalian liver has not been elucidated. Here we perform single-cell RNA sequencing on non-parenchymal cells isolated from healthy and NASH mouse livers. Secretome gene analysis revealed a highly connected network of intrahepatic signaling and disruption of vascular signaling in NASH. We uncovered the emergence of NASH-associated macrophages (NAMs), which are marked by high expression of triggering receptors expressed on myeloid cells 2 (Trem2), as a feature of mouse and human NASH that is linked to disease severity and highly responsive to pharmacological and dietary interventions. Finally, hepatic stellate cells (HSCs) serve as a hub of intrahepatic signaling via HSC-derived stellakines and their responsiveness to vasoactive hormones. These results provide unprecedented insights into the landscape of intercellular crosstalk and reprogramming of liver cells in health and disease.
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Comunicación Celular/genética , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Análisis de Secuencia de ARN , Animales , Reprogramación Celular/genética , Modelos Animales de Enfermedad , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Humanos , Ligandos , Hígado/patología , Macrófagos/metabolismo , Macrófagos/patología , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Transducción de Señal/genética , Análisis de la Célula IndividualRESUMEN
The human DNA repair factor CtIP helps to initiate the resection of double-stranded DNA breaks for repair by homologous recombination, in part through its ability to bind and bridge DNA molecules. However, CtIP is a natively disordered protein that bears no apparent similarity to other DNA-binding proteins and so the structural basis for these activities remains unclear. In this work, we have used bulk DNA binding, single molecule tracking, and DNA bridging assays to study wild-type and variant CtIP proteins to better define the DNA binding domains and the effects of mutations associated with inherited human disease. Our work identifies a monomeric DNA-binding domain in the C-terminal region of CtIP. CtIP binds non-specifically to DNA and can diffuse over thousands of nucleotides. CtIP-mediated bridging of distant DNA segments is observed in single-molecule magnetic tweezers experiments. However, we show that binding alone is insufficient for DNA bridging, which also requires tetramerization via the N-terminal domain. Variant CtIP proteins associated with Seckel and Jawad syndromes display impaired DNA binding and bridging activities. The significance of these findings in the context of facilitating DNA break repair is discussed.
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Proteínas Portadoras , ADN , Proteínas Nucleares , Unión Proteica , Humanos , ADN/metabolismo , ADN/genética , ADN/química , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/química , Proteínas Portadoras/metabolismo , Proteínas Portadoras/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/química , Mutación , Dominios Proteicos , Endodesoxirribonucleasas/metabolismo , Endodesoxirribonucleasas/genética , Endodesoxirribonucleasas/química , Roturas del ADN de Doble Cadena , Sitios de UniónRESUMEN
BACKGROUND: Plasma concentration of PAI-1 (plasminogen activator inhibitor-1) correlates with arterial stiffness. Vascular smooth muscle cells (SMCs) express PAI-1, and the intrinsic stiffness of SMCs is a major determinant of total arterial stiffness. We hypothesized that PAI-1 promotes SMC stiffness by regulating the cytoskeleton and that pharmacological inhibition of PAI-1 decreases SMC and aortic stiffness. METHODS: PAI-039, a specific inhibitor of PAI-1, and small interfering RNA were used to inhibit PAI-1 expression in cultured human SMCs. Effects of PAI-1 inhibition on SMC stiffness, F-actin (filamentous actin) content, and cytoskeleton-modulating enzymes were assessed. WT (wild-type) and PAI-1-deficient murine SMCs were used to determine PAI-039 specificity. RNA sequencing was performed to determine the effects of PAI-039 on SMC gene expression. In vivo effects of PAI-039 were assessed by aortic pulse wave velocity. RESULTS: PAI-039 significantly reduced intrinsic stiffness of human SMCs, which was accompanied by a significant decrease in cytoplasmic F-actin content. PAI-1 gene knockdown also decreased cytoplasmic F-actin. PAI-1 inhibition significantly increased the activity of cofilin, an F-actin depolymerase, in WT murine SMCs, but not in PAI-1-deficient SMCs. RNA-sequencing analysis suggested that PAI-039 upregulates AMPK (AMP-activated protein kinase) signaling in SMCs, which was confirmed by Western blotting. Inhibition of AMPK prevented activation of cofilin by PAI-039. In mice, PAI-039 significantly decreased aortic stiffness and tunica media F-actin content without altering the elastin or collagen content. CONCLUSIONS: PAI-039 decreases intrinsic SMC stiffness and cytoplasmic stress fiber content. These effects are mediated by AMPK-dependent activation of cofilin. PAI-039 also decreases aortic stiffness in vivo. These findings suggest that PAI-1 is an important regulator of the SMC cytoskeleton and that pharmacological inhibition of PAI-1 has the potential to prevent and treat cardiovascular diseases involving arterial stiffening.
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Endothelial insulin resistance represents a causal factor in the pathogenesis of type 2 diabetes (T2D) and vascular disease, thus the need to identify molecular mechanisms underlying defects in endothelial insulin signaling. We previously have shown that a disintegrin and metalloproteinase-17 (ADAM17) is increased while insulin receptor α-subunit (IRα) is decreased in the vasculature of patients with T2D, leading to impaired insulin-induced vasodilation. We have also demonstrated that ADAM17 sheddase activity targets IRα; however, the mechanisms driving endothelial ADAM17 activity in T2D are largely unknown. Herein, we report that externalization of phosphatidylserine (PS) to the outer leaflet of the plasma membrane causes ADAM17-mediated shedding of IRα and blunting of insulin signaling in endothelial cells. Furthermore, we demonstrate that endothelial PS externalization is mediated by the phospholipid scramblase anoctamin-6 (ANO6) and that this process can be stimulated by neuraminidase, a soluble enzyme that cleaves sialic acid residues. Of note, we demonstrate that men and women with T2D display increased levels of neuraminidase activity in plasma, relative to age-matched healthy individuals, and this occurs in conjunction with increased ADAM17 activity and impaired leg blood flow responses to endogenous insulin. Collectively, this work reveals the neuraminidase-ANO6-ADAM17 axis as a novel potential target for restoring endothelial insulin sensitivity in T2D.NEW & NOTEWORTHY This work provides the first evidence that neuraminidase, an enzyme increased in the circulation of men and women with type 2 diabetes (T2D), promotes anoctamin-6 (ANO6)-dependent externalization of phosphatidylserine in endothelial cells, which in turn leads to activation of a disintegrin and metalloproteinase-17 (ADAM17) and consequent shedding of the insulin receptor-α from the cell surface. Hence, this work supports that consideration should be given to the neuraminidase-ANO6-ADAM17 axis as a novel potential target for restoring endothelial insulin sensitivity in T2D.
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Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Masculino , Humanos , Femenino , Células Endoteliales/metabolismo , Receptor de Insulina/metabolismo , Fosfatidilserinas/metabolismo , Neuraminidasa/metabolismo , Insulina/metabolismo , Desintegrinas , Proteína ADAM17/metabolismo , Anoctaminas/metabolismoRESUMEN
This study determines the functional role of the plant ultraviolet-B radiation (UV-B) photoreceptor, UV RESISTANCE LOCUS 8 (UVR8) under natural conditions using a large-scale 'synchronized-genetic-perturbation-field-experiment'. Laboratory experiments have demonstrated a role for UVR8 in UV-B responses but do not reflect the complexity of outdoor conditions where 'genotype × environment' interactions can mask laboratory-observed responses. Arabidopsis thaliana knockout mutant, uvr8-7, and the corresponding Wassilewskija wild type, were sown outdoors on the same date at 21 locations across Europe, ranging from 39°N to 67°N latitude. Growth and climatic data were monitored until bolting. At the onset of bolting, rosette size, dry weight, and phenolics and glucosinolates were quantified. The uvr8-7 mutant developed a larger rosette and contained less kaempferol glycosides, quercetin glycosides and hydroxycinnamic acid derivatives than the wild type across all locations, demonstrating a role for UVR8 under field conditions. UV effects on rosette size and kaempferol glycoside content were UVR8 dependent, but independent of latitude. In contrast, differences between wild type and uvr8-7 in total quercetin glycosides, and the quercetin-to-kaempferol ratio decreased with increasing latitude, that is, a more variable UV response. Thus, the large-scale synchronized approach applied demonstrates a location-dependent functional role of UVR8 under natural conditions.
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With the continuous development of genetics in healthcare, there has been a significant contribution to the development of precision medicine, which is ultimately aimed at improving the care of patients. Generally, drug treatments used in Oncology are characterized by a narrow therapeutic range and by their potential toxicity. Knowledge of pharmacogenomics and pharmacogenetics can be very useful in the area of Oncology, as they constitute additional tools that can help to individualize patients' treatment. This work includes a description of some genes that have been revealed to be useful in the field of Oncology, as they play a role in drug prescription and in the prediction of treatment response.
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Encephalocraniocutaneous lipomatosis (ECCL) is a rare genetic condition with well-described skin, ocular, and central nervous system findings. Several case reports have been documented demonstrating the presence of low-grade gliomas in patients with ECCL and the association with certain FGFR1 mutations. We report on a case of diffuse low-grade glioma, mitogen activated protein kinase pathway altered in a patient with ECCL, who was found to have a distinct FGFR1 mutation.
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OBJECTIVE: This study aimed to examine fetal and neonatal inflammatory and neurologic complications associated with maternal coronavirus disease 2019 (COVID-19) infection. STUDY DESIGN: Case-series using a convenience sample of neonates cared for in a large referral-based children's hospital neonatal intensive care unit between September 2021 and May 2022. RESULTS: We identified seven neonates with exposure to maternal severe acute respiratory syndrome related coronavirus 2 (SARS-CoV-2) and a presentation consistent with inflammatory complications. All had some degree of neurologic injury with neuroimaging findings including restricted diffusion indicating injury in the white matter, cortex, deep gray structures, and splenium of the corpus callosum as well as intracranial hemorrhage. In addition, many infants had cytopenia and abnormal coagulation studies. Placental pathology, when available, revealed inflammation, clot with calcifications, and hematomas with associated infarcts. CONCLUSION: Neonates born to mothers with SARS-CoV-2, even when negative for the virus themselves, may have complications consistent with a systemic inflammatory syndrome. Placental pathology as well as neurologic imaging in infants with neurologic findings may help to support this diagnosis. KEY POINTS: · A systemic inflammatory response may cause illness in babies born to mothers with a history of COVID-19.. · Inflammatory markers and placental pathology are helpful in supporting this diagnosis.. · Consider neuroimaging in infants of mothers with a history of COVID-19 with neurologic findings..
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COVID-19 , Complicaciones Infecciosas del Embarazo , SARS-CoV-2 , Síndrome de Respuesta Inflamatoria Sistémica , Humanos , COVID-19/complicaciones , Femenino , Embarazo , Recién Nacido , Complicaciones Infecciosas del Embarazo/virología , Masculino , Placenta/patología , Placenta/virología , Adulto , Transmisión Vertical de Enfermedad Infecciosa , NeuroimagenRESUMEN
BACKGROUND AND AIMS: While endomyocardial biopsy (EMB) is recommended in adult patients with fulminant myocarditis, the clinical impact of its timing is still unclear. METHODS: Data were collected from 419 adult patients with clinically suspected fulminant myocarditis admitted to intensive care units across 36 tertiary centres in 15 countries worldwide. The diagnosis of myocarditis was histologically proven in 210 (50%) patients, either by EMB (n = 183, 44%) or by autopsy/explanted heart examination (n = 27, 6%), and clinically suspected cardiac magnetic resonance imaging confirmed in 96 (23%) patients. The primary outcome of survival free of heart transplantation (HTx) or left ventricular assist device (LVAD) at 1 year was specifically compared between patients with early EMB (within 2 days after intensive care unit admission, n = 103) and delayed EMB (n = 80). A propensity score-weighted analysis was done to control for confounders. RESULTS: Median age on admission was 40 (29-52) years, and 322 (77%) patients received temporary mechanical circulatory support. A total of 273 (65%) patients survived without HTx/LVAD. The primary outcome was significantly different between patients with early and delayed EMB (70% vs. 49%, P = .004). After propensity score weighting, the early EMB group still significantly differed from the delayed EMB group in terms of survival free of HTx/LVAD (63% vs. 40%, P = .021). Moreover, early EMB was independently associated with a lower rate of death or HTx/LVAD at 1 year (odds ratio of 0.44; 95% confidence interval: 0.22-0.86; P = .016). CONCLUSIONS: Endomyocardial biopsy should be broadly and promptly used in patients admitted to the intensive care unit for clinically suspected fulminant myocarditis.
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Trasplante de Corazón , Miocarditis , Adulto , Humanos , Miocarditis/complicaciones , Biopsia/métodos , Cateterismo Cardíaco , Imagen por Resonancia Magnética , Estudios Retrospectivos , Miocardio/patologíaRESUMEN
The ageing of the population needs the automation of patient monitoring. The objective of this is twofold: to improve care and reduce costs. Frailty, as a state of increased vulnerability resulting from several diseases, can be seen as a pandemic for older people. One of the most common detection tests is gait speed. This article compares the gait speed measured outdoors using smartphones with that measured using manual tests conducted in medical centres. In the experiments, the walking speed was measured over a straight path of 80 m. Additionally, the speed was measured over 2.4 m in the middle of the path, given that this is the minimum distance used in medical frailty tests. To eliminate external factors, the participants were healthy individuals, the weather was good, and the path was flat and free of obstacles. The results obtained are promising. The measurements taken with common smartphones over a straight path of 80 m are within the same order of error as those observed in the manual tests conducted by practitioners.
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Fragilidad , Teléfono Inteligente , Humanos , Fragilidad/diagnóstico , Fragilidad/fisiopatología , Masculino , Anciano , Femenino , Sistemas de Información Geográfica , Velocidad al Caminar/fisiología , Marcha/fisiología , Adulto , Evaluación Geriátrica/métodosRESUMEN
INTRODUCTION: Granulocyte and monocyte adsorptive apheresis (GMA) removes neutrophils and monocytes from peripheral blood, preventing their incorporation into the inflamed tissue also influencing cytokine balance. Published therapeutic efficacy in ulcerative colitis (UC) is more consistent than in Crohn's disease (CD). We assessed clinical efficacy of GMA in UC and CD 4 weeks after last induction session, at 3 and 12 months, sustained remission and corticosteroid-free remission. PATIENTS AND METHOD: Retrospective observational study of UC and CD patients treated with GMA. Partial Disease Activity Index-DAIp in UC and Harvey-Bradshaw Index-HBI in CD assessed efficacy of Adacolumn® with induction and optional maintenance sessions. RESULTS: We treated 87 patients (CD-25, UC-62), 87.3% corticosteroid-dependent (CSD), 42.5% refractory/intolerant to immunomodulators. In UC, remission and response were 32.2% and 19.3% after induction, 35.5% and 6.5% at 12 weeks and 29% and 6.5% at 52 weeks. In CD, remission rates were 60%, 52% and 40% respectively. In corticosteroid-dependent and refractory or intolerant to INM patients (UC-41, CD-14), 68.3% of UC achieved remission or response after induction, 51.2% at 12 weeks and 46.3% at 52 weeks, and 62.3%, 64.3% and 42.9% in CD. Maintained remission was achieved by 66.6% in CD and 53.1% in UC. Up to 74.5% of patients required corticosteroids at some timepoint. Corticosteroid-free response/remission was 17.7% in UC and 24% in CD. CONCLUSIONS: GMA is a good therapeutic tool for both in UC and CD patients. In corticosteroid-dependent and refractory or intolerant to INM patients it avoids biological therapy or surgery in up to 40% of them in one year.
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Difficulties in monitoring reading comprehension result in poor comprehension. One key aspect of monitoring is metacomprehension, which refers to one's awareness of one's own reading comprehension. Previous studies have observed difficulties in metacomprehension among the deaf or hard-of-hearing (DHH) population. This study aims to determine whether the metacomprehension of DHH students corresponds to their reading score and whether they are truly capable of adjusting their metacomprehension to the difficulty of the text. We evaluated 25 Spanish-speaking DHH students with reading scores approximately equivalent to Grades 5 or 6 of Primary School. Participants were asked to read a text and answer questions. The texts corresponded to three levels of difficulty (explicit, inferable, and noninferable). The results revealed that the metacomprehension of DHH students corresponded to their reading score. The DHH population may have better reading metacomprehension than is typically assumed, although the manifestation of this skill may depend on the type of task demanded of them (comprehension judgment or knowledge judgment).
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Cytochrome P450 3A4 (CYP3A4) is the dominant P450 involved in human xenobiotic metabolism. Competition for CYP3A4 therefore underlies several adverse drug-drug interactions. Despite its clinical significance, the mechanisms CYP3A4 uses to bind diverse ligands remain poorly understood. Highly monodisperse CYP3A4 embedded in anionic lipoprotein nanodiscs containing an equal mixture of 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) were used to determine which of the limiting kinetic schemes that include protein conformational change, conformational selection (CS) or induced fit (IF), best described the binding of four known irreversible inhibitors. Azamulin, retapamulin, pleuromutilin, and mibrefadil binding to CYP3A4 nanodiscs conformed to a single-site binding model. Exponential fits of stopped-flow UV-visible absorption spectroscopy data supported multiple-step binding mechanisms. Trends in the rates of relaxation to equilibrium with increasing ligand concentrations were ambiguous as to whether IF or CS was involved; however, global fitting and consideration of the rate constants favored an IF mechanism. In the case of mibrefadil, a transient complex was observed in the stopped-flow UV-visible experiment, definitively assigning the presence of IF in ligand binding. While these studies only consider a small region of CYP3A4's vast ligand space, they provide kinetic evidence that CYP3A4 can use an IF mechanism. SIGNIFICANCE STATEMENT: CYP3A4 is capable of oxidizing numerous xenobiotics, including many drugs. Such promiscuity could not be achieved without conformational changes to accommodate diverse substrates. It is unknown whether conformational heterogeneity is present before (conformational selection) or after (induced fit) ligand binding. Stopped-flow measurements of suicide inhibitors binding to nanodisc-embedded CYP3A4 combined with sophisticated numerical analyses support that induced fit better describes ligand binding to this important enzyme.
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Citocromo P-450 CYP3A , Sistema Enzimático del Citocromo P-450 , Humanos , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Ligandos , Conformación MolecularRESUMEN
Two pathways have been described for vulvar squamous cell carcinomas (VSCC), one associated with human papillomavirus (HPV), and the other HPV-independent. We compared the etiopathogenic features of a series of VSCC from Mozambique, a sub-Saharan country with high prevalence of HPV and HIV, with those of Spain, a European country with low prevalence of HPV and HIV. All VSCC diagnosed at the two institutions from January 2018 to December 2020 were included (n = 35 and n = 41, respectively). HPV DNA detection and genotyping, and immunohistochemistry for p16 and p53 were performed. Tumors showing p16 positive staining and/or HPV DNA positivity were considered HPV-associated. 34/35 tumors (97%) from Mozambique and 8/41 (19%) from Spain were HPV-associated (P < .001). Mean age of the patients from Mozambique and Spain was 45 ± 12 and 72 ± 14, respectively (P < .001). No differences were found in terms of HPV genotypes or multiple HPV infection rates. 1/35 tumors (3%) from Mozambique and 29/41 (70%) from Spain showed abnormal p53 immunostaining (P < .001). In contrast with the predominance of HPV-independent VSCC affecting old women in Europe, most VSCC in sub-Saharan Africa are HPV-associated and arise in young women. This data may have important consequences for primary prevention of VSCC worldwide.
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Carcinoma de Células Escamosas , Infecciones por VIH , Infecciones por Papillomavirus , Neoplasias de la Vulva , Humanos , Femenino , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/diagnóstico , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Neoplasias de la Vulva/epidemiología , Neoplasias de la Vulva/etiología , Neoplasias de la Vulva/diagnóstico , Papillomaviridae/genética , Papillomaviridae/metabolismo , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/metabolismo , Infecciones por VIH/complicaciones , Mozambique/epidemiología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismoRESUMEN
In the year 2002, DNA loss model (DNA-LM) postulated that neuropeptide genes to emerged through codons loss via the repair of damaged DNA from ancestral gene namely Neuropeptide Precursor Predictive (NPP), which organization correspond two or more neuropeptides precursors evolutive related. The DNA-LM was elaborated according to amino acids homology among LWamide, APGWamide, red pigment-concentrating hormone (RPCH), adipokinetic hormones (AKHs) and in silico APGW/RPCH NPPAPGW/AKH NPP were proposed. With the above principle, it was proposed the evolution of corazonin (CRZ), gonadotropin-releasing hormone (GnRH), AKH, and AKH/CRZ (ACP), but any NPP never was considered. However, the evolutive relation via DNA-LM among these neuropeptides precursors not has been established yet. Therefore, the transcriptomes from crabs Callinectes toxotes and Callinectes arcuatus were used to characterized ACP and partial CRZ precursors, respectively. BLAST alignment with APGW/RPCH NPP and APGW/AKH NPP allow identified similar NPP in the rotifer Brachionus plicatilis and other invertebrates. Moreover, three bioinformatics algorithms and manual verification were used to purify 13,778 sequences, generating a database with 719 neuropeptide precursors. Phylogenetic trees with the DNA-LM parameters showed that some ACP, CRZ, AKH2 and two NPP share nodes with GnRH from vertebrates and some of this neuropeptide had nodes in invertebrates. Whereas the phylogenetic tree with standard parameters do not showed previous node pattern. Robinson-Foulds metric corroborates the differences among phylogenetic trees. Homology relationship showed four putative orthogroups; AKH4, CRZ, and protostomes GnRH had individual group. This is the first demonstration of NPP in species and would explain the evolution neuropeptide families by the DNA-LM.
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Hormona Liberadora de Gonadotropina , Neuropéptidos , Humanos , Animales , Hormona Liberadora de Gonadotropina/genética , Hormona Liberadora de Gonadotropina/metabolismo , Filogenia , Evolución Molecular , Neuropéptidos/genética , Neuropéptidos/química , Neuropéptidos/metabolismo , Invertebrados/genética , ADN/metabolismoRESUMEN
Neuraminidases cleave sialic acids from glycocalyx structures and plasma neuraminidase activity is elevated in type 2 diabetes (T2D). Therefore, we hypothesize circulating neuraminidase degrades the endothelial glycocalyx and diminishes flow-mediated dilation (FMD), whereas its inhibition restores shear mechanosensation and endothelial function in T2D settings. We found that compared with controls, subjects with T2D have higher plasma neuraminidase activity, reduced plasma nitrite concentrations, and diminished FMD. Ex vivo and in vivo neuraminidase exposure diminished FMD and reduced endothelial glycocalyx presence in mouse arteries. In cultured endothelial cells, neuraminidase reduced glycocalyx coverage. Inhalation of the neuraminidase inhibitor, zanamivir, reduced plasma neuraminidase activity, enhanced endothelial glycocalyx length, and improved FMD in diabetic mice. In humans, a single-arm trial (NCT04867707) of zanamivir inhalation did not reduce plasma neuraminidase activity, improved glycocalyx length, or enhanced FMD. Although zanamivir plasma concentrations in mice reached 225.8 ± 22.0 ng/mL, in humans were only 40.0 ± 7.2 ng/mL. These results highlight the potential of neuraminidase inhibition for ameliorating endothelial dysfunction in T2D and suggest the current Food and Drug Administration-approved inhaled dosage of zanamivir is insufficient to achieve desired outcomes in humans.NEW & NOTEWORTHY This work identifies neuraminidase as a key mediator of endothelial dysfunction in type 2 diabetes that may serve as a biomarker for impaired endothelial function and predictive of development and progression of cardiovascular pathologies associated with type 2 diabetes (T2D). Data show that intervention with the neuraminidase inhibitor zanamivir at effective plasma concentrations may represent a novel pharmacological strategy for restoring the glycocalyx and ameliorating endothelial dysfunction.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Enfermedades Vasculares , Ratones , Humanos , Animales , Zanamivir/farmacología , Neuraminidasa/química , Neuraminidasa/farmacología , Células Endoteliales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Antivirales/farmacología , Inhibidores Enzimáticos/farmacologíaRESUMEN
Debaryomyces hansenii is a halotolerant/halophilic yeast usually found in salty environments. The yeast accumulated sodium at high concentrations, which improved growth in salty media. In contrast, lithium was toxic even at low concentrations and its presence prevented cell proliferation. To analyse the responses to both cations, metabolite levels, enzymatic activities and gene expression were determined, showing that NaCl and LiCl trigger different cellular responses. At high concentrations of NaCl (0.5 or 1.5 M) cells accumulated higher amounts of the intermediate metabolites glyoxylate and malate and, at the same time, the levels of intracellular oxoglutarate decreased. Additionally, 0.5 M NaCl increased the activity of the enzymes isocitrate lyase and malate synthase involved in the synthesis of glyoxylate and malate respectively and decreased the activity of isocitrate dehydrogenase. Moreover, transcription of the genes coding for isocitrate lyase and malate synthase was activated by NaCl. Also, cells accumulated phosphate upon NaCl exposure. None of these effects was provoked when LiCl (0.1 or 0.3 M) was used instead of NaCl. Lithium induced accumulation of higher amounts of oxoglutarate and decreased the concentrations of glyoxylate and malate to non-detectable levels. Cells incubated with lithium also showed higher activity of the isocitrate dehydrogenase and neither increased isocitrate lyase and malate synthase activities nor the transcription of the corresponding genes. In summary, we show that sodium, but not lithium, up regulates the shunt of the glyoxylic acid in D. hansenii and we propose that this is an important metabolic adaptation to thrive in salty environments.
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Debaryomyces , Sodio , Cloruro de Sodio/farmacología , Malato Sintasa/genética , Malato Sintasa/metabolismo , Isocitratoliasa/genética , Isocitratoliasa/metabolismo , Malatos , Debaryomyces/metabolismo , Saccharomyces cerevisiae/metabolismo , Isocitrato Deshidrogenasa/genética , Carbono , Ácidos Cetoglutáricos , Glioxilatos/metabolismoRESUMEN
Vascular insulin resistance, a major characteristic of obesity and type 2 diabetes (T2D), manifests with blunting of insulin-induced vasodilation. Although there is evidence that females are more whole body insulin sensitive than males in the healthy state, whether sex differences exist in vascular insulin sensitivity is unclear. Also uncertain is whether weight loss can reestablish vascular insulin sensitivity in T2D. The purpose of this investigation was to 1) establish if sex differences in vasodilatory responses to insulin exist in absence of disease, 2) determine whether female sex affords protection against the development of vascular insulin resistance with long-term overnutrition and obesity, and 3) examine if diet-induced weight loss can restore vascular insulin sensitivity in men and women with T2D. First, we show in healthy mice and humans that sex does not influence insulin-induced femoral artery dilation and insulin-stimulated leg blood flow, respectively. Second, we provide evidence that female mice are protected against impairments in insulin-induced dilation caused by overnutrition-induced obesity. Third, we show that men and women exhibit comparable levels of vascular insulin resistance when T2D develops but that diet-induced weight loss is effective at improving insulin-stimulated leg blood flow, particularly in women. Finally, we provide indirect evidence that these beneficial effects of weight loss may be mediated by a reduction in endothelin-1. In aggregate, the present data indicate that female sex confers protection against obesity-induced vascular insulin resistance and provide supportive evidence that, in women with T2D, vascular insulin resistance can be remediated with diet-induced weight loss.
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Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Humanos , Femenino , Masculino , Ratones , Animales , Resistencia a la Insulina/fisiología , Insulina , Obesidad , Pérdida de Peso , Arteria Femoral , DietaRESUMEN
BACKGROUND: Achieving and maintaining a low-risk profile is associated with favorable outcome in pulmonary arterial hypertension (PAH). The effects of treatment on risk profile are variable among patients. OBJECTIVE: To Identify variables that might predict the response to treatment with phosphodiesterase-5 inhibitors (PDE-5i) in PAH. METHODS: We carried out a cohort analysis of the Spanish PAH registry in 830 patients diagnosed with PAH that started PDE5i treatment and had > 1 year follow-up. 644 patients started PDE-5i either in mono- or add-on therapy and 186 started combined treatment with PDE-5i and endothelin receptor antagonist (ERA). Responders were considered when at 1 year they: (1) were alive; (2) did not present clinical worsening; and (3) improved European Society of Cardiology/European Respiratory Society (ESC/ERS) risk score or remained in low-risk. Univariate and multivariate logistic regression models were used to analyze variables associated with a favorable response. RESULTS: Two hundred and ten patients (33%) starting PDE-5i alone were classified as responders, irrespective of whether it was mono- or add-on therapy. In addition to known predictors of PAH outcome (low-risk at baseline, younger age), male sex and diagnosis of portopulmonary hypertension (PoPH) or HIV-PAH were independent predictors of favorable response to PDE-5i. Diffusing capacity for carbon monoxide (DLco) ≤ 40% of predicted was associated with an unfavorable response. When PDE-5i were used in upfront combination, 58% of patients were responders. In this group, diagnosis of idiopathic PAH (IPAH) was an independent predictor of favorable response, whereas connective tissue disease-PAH was associated with an unfavorable response. CONCLUSION: Male sex and diagnosis of PoPH or HIV-PAH are predictors of favorable effect of PDE-5i on risk profile when used as mono- or add-on therapy. Patients with IPAH respond more favorably to PDE-5i when used in upfront combination. These results identify patient profiles that may respond favorably to PDE-5i in monotherapy and those who might benefit from alternative treatment strategies.
Asunto(s)
Infecciones por VIH , Hipertensión Arterial Pulmonar , Humanos , Masculino , Hipertensión Arterial Pulmonar/diagnóstico , Hipertensión Arterial Pulmonar/tratamiento farmacológico , Hipertensión Arterial Pulmonar/epidemiología , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5 , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Hipertensión Pulmonar Primaria Familiar , Sistema de RegistrosRESUMEN
Calcium phosphate nanoparticles were doped with zinc ions to produce multifunctional nanomaterials for efficient agronomic fortification and protection of plants. The resulting round-shaped nanoparticles (nanoZn) were composed of 20.3 wt % Ca, 14.8 wt % P, and 13.4 wt % Zn and showed a pH-controlled solubility. NanoZn were stable in aqueous solutions at neutral pH but dissolved in citric acid at pH 4.5 (i.e., the pH inside tomato fruits), producing a pH-responsive delivery of the essential nutrients Ca, P, and Zn. In fact, the foliar application of nanoZn on tomato plants provided tomatoes with the highest Zn, Ca, and P contents (causing, respectively, a 65, 65, and 15% increase with respect to a conventional treatment with ZnSO4) and the highest yields. Additionally, nanoZn (100 ppm of Zn) inhibited in vitro the growth of Pseudomonas syringae (Ps), the main cause of bacterial speck, and significantly reduced Ps incidence and mortality in tomato seeds, previously inoculated with the pathogen. Therefore, nanoZn present dual agricultural applicability, enriching crops with nutrients with important metabolic functions in humans and simultaneously protecting the plants against important bacterial-based diseases, with considerable negative impact in crop production.