RESUMEN
This study aimed to comprehensively assess the metabolic, mitochondrial, and inflammatory effects of first-line efavirenz, emtricitabine, and tenofovir disoproxil fumarate (EFV/FTC/TDF) single-tablet regimen (STR) relative to untreated asymptomatic HIV infection. To this end, we analyzed 29 people with HIV (PWH) treated for at least one year with this regimen vs. 33 antiretroviral-naïve PWH. Excellent therapeutic activity was accompanied by significant alterations in metabolic parameters. The treatment group showed increased plasmatic levels of glucose, total cholesterol and its fractions (LDL and HDL), triglycerides, and hepatic enzymes (GGT, ALP); conversely, bilirubin levels (total and indirect fraction) decreased in the treated cohort. Mitochondrial performance was preserved overall and treatment administration even promoted the recovery of mitochondrial DNA (mtDNA) content depleted by the virus, although this was not accompanied by the recovery in some of their encoded proteins (since cytochrome c oxidase II was significantly decreased). Inflammatory profile (TNFα, IL-6), ameliorated after treatment in accordance with viral reduction and the recovery of TNFα levels correlated to mtDNA cell restoration. Thus, although this regimen causes subclinical metabolic alterations, its antiviral and anti-inflammatory properties may be associated with partial improvement in mitochondrial function.
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Alquinos , Fármacos Anti-VIH , Benzoxazinas , Ciclopropanos , ADN Mitocondrial , Emtricitabina , Infecciones por VIH , Mitocondrias , Tenofovir , Humanos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/metabolismo , Masculino , Femenino , Adulto , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Benzoxazinas/uso terapéutico , Benzoxazinas/farmacología , Fármacos Anti-VIH/uso terapéutico , Fármacos Anti-VIH/efectos adversos , Ciclopropanos/uso terapéutico , Tenofovir/uso terapéutico , Persona de Mediana Edad , Emtricitabina/uso terapéutico , ADN Mitocondrial/metabolismo , InflamaciónRESUMEN
Oxidized cholesterol metabolite 27-hydroxycholesterol (27-OH) is a potential link between hypercholesterolemia and neurodegenerative diseases since unlike peripheral cholesterol, 27-OH is transported across the blood-brain barrier. However, the effects of high 27-OH levels on oligodendrocyte function remain unexplored. We hypothesize that during hypercholesterolemia 27-OH may impact oligodendrocytes and myelin and thus contribute to the disconnection of neural networks in neurodegenerative diseases. To test this idea, we first investigated the effects of 27-OH in cultured oligodendrocytes and found that it induces cell death of immature O4+ /GalC+ oligodendrocytes along with stimulating differentiation of PDGFR+ oligodendrocyte progenitors (OPCs). Next, transgenic mice with increased systemic 27-OH levels (Cyp27Tg) underwent behavioral testing and their brains were immunohistochemically stained and lysed for immunoblotting. Chronic exposure to 27-OH in mice resulted in increased myelin basic protein (MBP) but not 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase) or myelin oligodendrocyte glycoprotein (MOG) levels in the corpus callosum and cerebral cortex. Intriguingly, we also found impairment of spatial learning suggesting that subtle changes in myelinated axons of vulnerable areas like the hippocampus caused by 27-OH may contribute to impaired cognition. Finally, we found that 27-OH levels in cerebrospinal fluid from memory clinic patients were associated with levels of the myelination regulating CNPase, independently of Alzheimer's disease markers. Thus, 27-OH promotes OPC differentiation and is toxic to immature oligodendrocytes as well as it subtly alters myelin by targeting oligodendroglia. Taken together, these data indicate that hypercholesterolemia-derived higher 27-OH levels change the oligodendrocytic capacity for appropriate myelin remodeling which is a crucial factor in neurodegeneration and aging.
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Hipercolesterolemia , Sustancia Blanca , Ratones , Animales , Sustancia Blanca/metabolismo , Hipercolesterolemia/metabolismo , Encéfalo/metabolismo , Vaina de Mielina/metabolismo , Oligodendroglía/metabolismo , Diferenciación Celular , 2',3'-Nucleótido Cíclico Fosfodiesterasas/metabolismo , Ratones TransgénicosRESUMEN
OBJECTIVE: The aim of this study is to assess Trypanosoma cruzi infection prevalence among pregnant migrants living in Madrid according to the country of origin and to assess screening coverage in this at-risk population. METHODS: Retrospective multicentre cross-sectional study conducted from January 2011 to December 2016 in eight Madrid hospitals. Each hospital reviewed their microbiology data records to assess the screening coverage and serological diagnosis in all pregnant women coming from endemic areas. RESULTS: From 2011 to 2016, 149,470 deliveries were attended at the eight hospitals, and 11,048 pregnant women were screened for Chagas disease. Most cases (93.5%) were in women from Bolivia, who also showed the highest prevalence (12.4%, 95% confidence interval: 9.9-15.0). Pooled prevalence amongst the screened women was 2.9% (95% CI: 1.8-4.1). Chagas disease screening coverage varied greatly between centres, with a pooled mean coverage of 47% (95% CI: 37%-57%; 73% [95% CI: 63%-82%] for those centres with universal screening vs. 10% [95% CI: 6%-15%] for those with a selective screening approach; p < 0.001). CONCLUSION: Our study provides useful data for policy makers and epidemiologists in a non-endemic area without congenital Chagas screening programmes.
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Enfermedad de Chagas , Trypanosoma cruzi , Femenino , Humanos , Embarazo , Mujeres Embarazadas , Estudios Transversales , España/epidemiología , Prevalencia , América Latina/epidemiología , Transmisión Vertical de Enfermedad Infecciosa , Enfermedad de Chagas/diagnósticoRESUMEN
BACKGROUND: The COVID-19 pandemic has significantly influenced the routine of healthcare workers. This study investigated the impact of the pandemic on dental practice and dentists' feelings in Latin America. METHODS: A survey was conducted with dentists from 11 Spanish-speaking Latin American countries in September-December 2020. Professionals were invited by email and via an open campaign promoted on social media. The questions investigated dental care routines, practice changes, and feelings about the pandemic. Descriptive statistics were used to identify frequencies and distributions of variables. Proportions were compared using chi-square tests. RESULTS: A total of 2127 responses were collected from a sample with diverse demographic, sex, work, and education characteristics. The impact of COVID-19 was considered high/very high by 60% of respondents. The volume of patients assisted weekly was lower compared with the pre-pandemic period (mean reduction = 14 ± 15 patients). A high rate of fear to contracting the COVID-19 at work was observed (85%); 4.9% of participants had a positive COVID-19 test. The main professional challenges faced by respondents were reduction in the number of patients or financial gain (35%), fear of contracting COVID-19 (34%), and burden with or difficulty in purchasing new personal protective equipment (22%). The fear to contracting COVID-19 was influenced by the number of weekly appointments. A positive test by the dentists was associated with their reports of having assisted COVID-19 patients. The most cited feelings about the pandemic were uncertainty, fear, worry, anxiety, and stress. Negative feelings were more prevalent for professionals who did not receive training for COVID-19 preventive measures and those reporting higher levels of fear to contract the disease. CONCLUSION: This multi-country survey indicated a high impact of the pandemic on dental care routines in Latin America. A massive prevalence of bad feelings was associated with the pandemic.
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COVID-19 , COVID-19/epidemiología , Odontólogos , Emociones , Humanos , América Latina/epidemiología , Pandemias , Encuestas y CuestionariosRESUMEN
Glial cells participate actively in the early cognitive decline in Alzheimer's disease (AD) pathology. In fact, recent studies have found molecular and functional abnormalities in astrocytes and microglia in both animal models and brains of patients suffering from this pathology. In this regard, reactive gliosis intimately associated with amyloid plaques has become a pathological hallmark of AD. A recent study from our laboratory reports that astrocyte reactivity is caused by a direct interaction between amyloid beta (Aß) oligomers and integrin ß1. Here, we have generated four recombinant peptides including the extracellular domain of integrin ß1, and evaluated their capacity both to bind in vitro to Aß oligomers and to prevent in vivo Aß oligomer-induced gliosis and endoplasmic reticulum stress. We have identified the minimal region of integrin ß1 that binds to Aß oligomers. This region is called signal peptide and corresponds to the first 20 amino acids of the integrin ß1 N-terminal domain. This recombinant integrin ß1 signal peptide prevented Aß oligomer-induced ROS generation in primary astrocyte cultures. Furthermore, we carried out intrahippocampal injection in adult mice of recombinant integrin ß1 signal peptide combined with or without Aß oligomers and we evaluated by immunohistochemistry both astrogliosis and microgliosis as well as endoplasmic reticulum stress. The results show that recombinant integrin ß1 signal peptide precluded both astrogliosis and microgliosis and endoplasmic reticulum stress mediated by Aß oligomers in vivo. We have developed a molecular tool that blocks the activation of the molecular cascade that mediates gliosis via Aß oligomer/integrin ß1 signaling.
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Péptidos beta-Amiloides , Gliosis , Integrina beta1 , Señales de Clasificación de Proteína , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Humanos , Integrina beta1/metabolismo , RatonesRESUMEN
Erythrostemon yucatanensis (Greenm.) Gagnon & GP Lewis is a legume tree native to and widely distributed in southeast Mexico, where its branches are used in traditional medicine. An in vitro evaluation of the antiviral activity of extracts and fractions from the leaves, stem bark and roots against two strains of the AH1N1 influenza virus was performed, leading to the identification of bioactive compounds in this medicinal plant. In a cytopathic effect reduction assay, the fractions from the leaves and stem bark were the active elements at the co-treatment level. These were further fractionated based on their hemagglutination inhibition activity. The analysis of spectroscopy data identified a combination of phytosterols (ß-sitosterol, stigmasterol and campesterol) in the stem bark active fraction as the main anti-hemagglutinin binding components, while 5-hydroxy-2(2-hydroxy-3,4,5-trimethoxyphenyl)-7-metoxi-4H(chromen-4-ona), which was isolated from the leaf extracts, showed a weak inhibition of viral hemagglutinin. Time of addition experiments demonstrated that the mixture of sterols had a direct effect on viral particle infectivity at the co-treatment level (IC50 = 3.125 µg/mL). This effect was also observed in the virus plaque formation inhibition assay, where the mixture showed 90% inhibition in the first 20 min of co-treatment at the same concentration. Additionally, it was found using qRT-PCR that the NP copy number was reduced by 92.85% after 60 min of co-treatment. These results are the first report of components with anti-hemagglutinin binding activity in the genus Erythrostemon sp.
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Fabaceae , Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Gripe Humana , Antivirales/química , Bioensayo , Hemaglutininas , Humanos , Extractos Vegetales/químicaRESUMEN
Fibroblast growth factor-21 (FGF21) is a hormonal regulator of metabolism; it promotes glucose oxidation and the thermogenic capacity of adipose tissues. The levels of ß-klotho (KLB), the co-receptor required for FGF21 action, are decreased in brown (BAT) and white (WAT) adipose tissues during obesity, diabetes, and lipodystrophy. Reduced ß-klotho levels have been proposed to account for FGF21 resistance in these conditions. In this study, we explored whether downregulation of ß-klotho affects metabolic regulation and the thermogenic responsiveness of adipose tissues using mice with total (KLB-KO) or partial (KLB-heterozygotes) ablation of ß-klotho. We herein show that KLB gene dosage was inversely associated with adiposity in mice. Upon cold exposure, impaired browning of subcutaneous WAT and milder alterations in BAT were associated with reduced KLB gene dosage in mice. Cultured brown and beige adipocytes from mice with total or partial ablation of the KLB gene showed reduced thermogenic responsiveness to ß3-adrenergic activation by treatment with CL316,243, indicating that these effects were cell-autonomous. Deficiency in FGF21 mimicked the KLB-reduction-induced impairment of thermogenic responsiveness in brown and beige adipocytes. These results indicate that the levels of KLB in adipose tissues determine their thermogenic capacity to respond to cold and/or adrenergic stimuli. Moreover, an autocrine action of FGF21 in brown and beige adipocytes may account for the ability of the KLB level to influence thermogenic responsiveness.NEW & NOTEWORTHY Reduced levels of KLB (the obligatory FGF21 co-receptor), as occurring in obesity and type 2 diabetes, reduce the thermogenic responsiveness of adipose tissues in cold-exposed mice. Impaired response to ß3-adrenergic activation in brown and beige adipocytes with reduced KLB occurs in a cell-autonomous manner involving an autocrine action of FGF21.
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Tejido Adiposo/metabolismo , Factores de Crecimiento de Fibroblastos/fisiología , Proteínas de la Membrana/fisiología , Termogénesis/genética , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo Pardo/efectos de los fármacos , Tejido Adiposo Pardo/metabolismo , Adiposidad/genética , Animales , Comunicación Autocrina/efectos de los fármacos , Comunicación Autocrina/genética , Células Cultivadas , Factores de Crecimiento de Fibroblastos/farmacología , Dosificación de Gen/fisiología , Proteínas Klotho , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Termogénesis/efectos de los fármacosRESUMEN
Chemokine (C-X-C motif) ligand-14 (CXCL14) levels are downregulated in experimental rodent models of obesity. Moreover, CXCL14 reportedly favors insulin sensitization in obese mice. Here we examined, for the first time, the role of CXCL14 in human obesity. We found that circulating levels of CXCL14 were decreased in patients with obesity and, especially, those with concomitant type-2 diabetes. CXCL14 levels were negatively associated with BMI and with indices of impaired glucose/insulin homeostasis. CXCL14 expression was decreased in subcutaneous adipose tissue from patients with obesity and type-2 diabetes. In adipose tissue, CXCL14 expression was negatively correlated with the expression of genes encoding pro-inflammatory molecules, and positively correlated with GLUT4 and adiponectin expression. In conclusion, obesity, and especially, concomitant type-2 diabetes are associated with abnormally decreased levels of CXCL14 in blood and impaired CXCL14 expression in adipose tissue. CXCL14 downregulation may be a novel biomarker of altered metabolism in obesity. CXCL14 also deserves further research as a therapeutic candidate.
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Quimiocinas CXC/sangre , Diabetes Mellitus Tipo 2 , Obesidad , Tejido Adiposo/química , Tejido Adiposo/metabolismo , Quimiocinas CXC/análisis , Quimiocinas CXC/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Humanos , Obesidad/sangre , Obesidad/complicaciones , Obesidad/epidemiologíaRESUMEN
Parkin is an ubiquitin-E3 ligase that acts as a key component of the cellular machinery for mitophagy. We show here that Parkin expression is reciprocally regulated in brown adipose tissue in relation to thermogenic activity. Thermogenic stimuli repress Parkin gene expression via transcriptional mechanisms that are elicited by noradrenergic and PPARα-mediated pathways that involve intracellular lipolysis in brown adipocytes. Parkin-KO mice show over-activated brown adipose tissue thermogenic activity and exhibit improved metabolic parameters, especially when fed a high-fat diet. Deacclimation, which is the return of a cold-adapted mouse to a thermoneutral temperature, dramatically induces mitophagy in brown adipocytes, with a concomitant induction of Parkin levels. We further reveal that Parkin-KO mice exhibit defects in the degradative processing of mitochondrial proteins in brown adipose tissue in response to deacclimation. These results suggest that the transcriptional control of Parkin in brown adipose tissue may contribute to modulating the mitochondrial mass and activity for adaptation to thermogenic requirements.
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Tejido Adiposo Pardo/metabolismo , Plasticidad de la Célula/fisiología , Termogénesis/fisiología , Ubiquitina-Proteína Ligasas/metabolismo , Adipocitos Marrones , Animales , Dieta Alta en Grasa , Regulación de la Expresión Génica/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mitocondrias/metabolismo , Mitofagia/fisiología , Transcripción Genética/fisiologíaRESUMEN
In this article, we investigated the inâ vitro potential beneficial effects of the anthocyanin cyanidin-3-O-glucoside (C3G) on inflammation and insulin resistance markers induced by palmitic acid (PA) in human SGBS adipocytes. Results demonstrated that PA reduced insulin sensitivity in SGBS cells with a significant inhibition of Akt phosphorylation, with a higher sensitivity to PA than murine 3T3-L1 adipocytes, GLUT-1 and GLUT-4 glucose transporters and the enzyme hexokinase-II. C3G pretreatment (1-20â µM) reverted these effects. Moreover, we demonstrated, for the first time in human adipocytes, that cells exposure to PA induced gene expression of proinflammatory cytokines TNF-α, IL-6, IL-8, and MCP-1. Cells pretreatment with C3G resulted in a reduction in mRNA levels starting at very low concentrations (1â µM). In conclusion, this study highlights the effects of PA on inflammation and insulin resistance markers in human adipocytes, and confirm the role of C3G in the prevention of lipotoxicity in dysfunctional adipocytes.
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Adipocitos/efectos de los fármacos , Antocianinas/farmacología , Citocinas/genética , Inflamación/tratamiento farmacológico , Ácido Palmítico/farmacología , Células 3T3-L1 , Animales , Antocianinas/química , Relación Dosis-Respuesta a Droga , Humanos , Inflamación/metabolismo , RatonesRESUMEN
Mitochondrial fission mediated by cytosolic dynamin related protein 1 (Drp1) is essential for mitochondrial quality control but may contribute to apoptosis as well. Blockade of Drp1 with mitochondrial division inhibitor 1 (mdivi-1) provides neuroprotection in several models of neurodegeneration and cerebral ischemia and has emerged as a promising therapeutic drug. In oligodendrocytes, overactivation of AMPA-type ionotropic glutamate receptors (AMPARs) induces intracellular Ca2+ overload and excitotoxic death that contributes to demyelinating diseases. Mitochondria are key to Ca2+ homeostasis, however it is unclear how it is disrupted during oligodendroglial excitotoxicity. In the current study, we have analyzed mitochondrial dynamics during AMPAR activation and the effects of mdivi-1 on excitotoxicity in optic nerve-derived oligodendrocytes. Sublethal AMPAR activation triggered Drp1-dependent mitochondrial fission, whereas toxic AMPAR activation produced Drp1-independent mitochondrial swelling. Accordingly, mdivi-1 efficiently inhibited Drp1-mediated mitochondrial fission and did not prevent oligodendrocyte excitotoxicity. Unexpectedly, mdivi-1 also induced mitochondrial depolarization, ER Ca2+ depletion and modulation of AMPA-induced Ca2+ signaling. These off-target effects of mdivi-1 sensitized oligodendrocytes to excitotoxicity and ER stress and eventually produced oxidative stress and apoptosis. Interestingly, in cultured astrocytes mdivi-1 induced nondetrimental mitochondrial depolarization and oxidative stress that did not cause toxicity or sensitization to apoptotic stimuli. In summary, our results provide evidence of Drp1-mediated mitochondrial fission during activation of ionotropic glutamate receptors in oligodendrocytes, and uncover a deleterious and Drp1-independent effect of mdivi-1 on mitochondrial and ER function in these cells. These off-target effects of mdivi-1 limit its therapeutic potential and should be taken into account in clinical studies.
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Dinámicas Mitocondriales , Quinazolinonas , Apoptosis , Dinaminas/metabolismo , Homeostasis , Mitocondrias/metabolismo , Oligodendroglía/metabolismo , Quinazolinonas/farmacología , Receptores Ionotrópicos de Glutamato , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol PropiónicoRESUMEN
As many tumor cells synthetize vascular endothelial growth factors (VEGF) that promote neo-vascularization and metastasis, frontline cancer therapies often administer anti-VEGF (α-VEGF) antibodies. To target the oncolytic parvovirus minute virus of mice (MVM) to the tumor vasculature, we studied the functional tolerance, evasion of neutralization, and induction of α-VEGF antibodies of chimeric viruses in which the footprint of a neutralizing monoclonal antibody within the 3-fold capsid spike was replaced by VEGF-blocking peptides: P6L (PQPRPL) and A7R (ATWLPPR). Both peptides allowed viral genome replication and nuclear translocation of chimeric capsid subunits. MVM-P6L efficiently propagated in culture, exposing the heterologous peptide on the capsid surface, and evaded neutralization by the anti-spike monoclonal antibody. In contrast, MVM-A7R yielded low infectious titers and was poorly recognized by an α-A7R monoclonal antibody. MVM-A7R showed a deficient assembly pattern, suggesting that A7R impaired a transitional configuration that the subunits must undergo in the 3-fold axis to close up the capsid shell. The MVM-A7R chimeric virus consistently evolved in culture into a mutant carrying the P6Q amino acid substitution within the A7R sequence, which restored normal capsid assembly and infectivity. Consistent with this finding, anti-native VEGF antibodies were induced in mice by a single injection of MVM-A7R empty capsids, but not by MVM-A7R virions. This fundamental study provides insights to endow an infectious parvovirus with immune antineovascularization and evasion capacities by replacing an antibody footprint in the capsid 3-fold axis with VEGF-blocking peptides, and it also illustrates the evolutionary capacity of single-stranded DNA (ssDNA) viruses to overcome engineered capsid structural restrictions.IMPORTANCE Targeting the VEGF signaling required for neovascularization by vaccination with chimeric capsids of oncolytic viruses may boost therapy for solid tumors. VEGF-blocking peptides (VEbp) engineered in the capsid 3-fold axis endowed the infectious parvovirus MVM with the ability to induce α-VEGF antibodies without adjuvant and to evade neutralization by MVM-specific antibodies. However, these properties may be compromised by structural restraints that the capsid imposes on the peptide configuration and by misassembly caused by the heterologous peptides. Significantly, chimeric MVM-VEbp resolved the structural restrictions by selecting mutations within the engineered peptides that restored efficient capsid assembly. These data show the promise of antineovascularization vaccines using chimeric VEbp-icosahedral capsids of oncolytic viruses but also raise safety concerns regarding the genetic stability of manipulated infectious parvoviruses in cancer and gene therapies.
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Vacunas contra el Cáncer/inmunología , Proteínas de la Cápside/inmunología , Proteínas de la Cápside/metabolismo , Virus Diminuto del Ratón/inmunología , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacunas contra el Cáncer/administración & dosificación , Vacunas contra el Cáncer/genética , Proteínas de la Cápside/genética , Ratones Endogámicos BALB C , Virus Diminuto del Ratón/genética , Virus Diminuto del Ratón/crecimiento & desarrollo , Virus Oncolíticos/genética , Virus Oncolíticos/crecimiento & desarrollo , Virus Oncolíticos/inmunología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Carga Viral , Ensamble de Virus , Acoplamiento Viral , Internalización del VirusRESUMEN
Adaptive induction of thermogenesis in brown adipose tissue (BAT) is essential for the survival of mammals after birth. We show here that G protein-coupled receptor protein 120 (GPR120) expression is dramatically induced after birth in mouse BAT. GPR120 expression in neonatal BAT is the highest among GPR120-expressing tissues in the mouse at any developmental stage tested. The induction of GPR120 in neonatal BAT is caused by postnatal thermal stress rather than by the initiation of suckling. GPR120-null neonates were found to be relatively intolerant to cold: close to one-third did not survive at 21°C, but all such pups survived at 25°C. Heat production in BAT was significantly impaired in GPR120-null pups. Deficiency in GPR120 did not modify brown adipocyte morphology or the anatomical architecture of BAT, as assessed by electron microscopy, but instead impaired the expression of uncoupling protein-1 and the fatty acid oxidation capacity of neonatal BAT. Moreover, GPR120 deficiency impaired fibroblast growth factor 21 (FGF21) gene expression in BAT and reduced plasma FGF21 levels. These results indicate that GPR120 is essential for neonatal adaptive thermogenesis.
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Tejido Adiposo Pardo/fisiología , Animales Recién Nacidos/fisiología , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/fisiología , Termogénesis/fisiología , Animales , Frío , Ácidos Grasos/metabolismo , Femenino , Factores de Crecimiento de Fibroblastos , Glucosa/metabolismo , Trastornos de Estrés por Calor/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Oxidación-Reducción , Palmitatos/metabolismo , Proteína Desacopladora 1/metabolismoRESUMEN
With the idea of proposing solid state systems that have a high storage capacity of molecular hydrogen, a density functional theory study of magnesium oxide (MgO)n clusters (n = 1-10) was carried out. Hydrogen-magnesium oxide systems presented adsorption energy values in accordance with the previously reported studies of physisorption processes; additionally negative values of ΔGads were found describing adsorption as a favorable process. Here, the (MgO)7 cluster presented the highest adsorption energy. The storage capacity by weight of the magnesium oxide clusters was greater than the recommended percentage (7.5%) by the U.S. Department of Energy. QTAIM analysis and non-covalent index plots highlighted the weak nature of the interaction between the MgO clusters and hydrogen molecules, and the fundamental role of the Mg-O bonds' polarity in the systems' storage capacity.
RESUMEN
Following antiretroviral therapy, HIV-infected patients show increased circulating levels of the antidiabetic hormone fibroblast growth factor 21 (FGF21). In contrast, the expression of the FGF21-obligatory coreceptor ß-Klotho (KLB) is reduced in target tissues. This situation is comparable to the FGF21 resistance status observed in obesity and type 2 diabetes. Here, we performed the first systematic study of the effects of distinct members of different antiretroviral drug classes on the FGF21/KLB system in human hepatic, adipose, and skeletal muscle cells. Most protease inhibitors and the nonnucleoside reverse transcriptase inhibitor efavirenz induced FGF21 gene expression. Neither nucleoside reverse transcriptase inhibitors nor the viral entry inhibitor maraviroc had any effect. Among the integrase inhibitors, elvitegravir significantly induced FGF21 expression, whereas raltegravir had minor effects only in adipose cells. In human hepatocytes and adipocytes, known target cells of FGF21 action, efavirenz, elvitegravir, and the lopinavir-ritonavir combination exerted inhibitory effects on KLB gene expression. Drug treatments that elicited FGF21 induction/KLB repression were those found to induce endoplasmic reticulum (ER) stress and oxidative stress. Notably, the pharmacological agents thapsigargin and tunicamycin, which induce these stress pathways, mimicked the effects of drug treatments. Moreover, pharmacological inhibitors of either ER or oxidative stress significantly impaired lopinavir-ritonavir-induced regulation of FGF21, but not KLB. In conclusion, the present in vitro screen study identifies the antiretroviral drugs that affect FGF21/KLB expression in human cells. The present results could have important implications for the management of comorbidities resulting from side effects of specific antiretroviral drugs for the treatment of HIV-infected patients.
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Tejido Adiposo/metabolismo , Antirretrovirales/farmacología , Factores de Crecimiento de Fibroblastos/análisis , Infecciones por VIH/tratamiento farmacológico , Hígado/metabolismo , Proteínas de la Membrana/análisis , Músculo Esquelético/metabolismo , Alquinos , Benzoxazinas/farmacología , Ciclopropanos , Diabetes Mellitus Tipo 2/patología , Combinación de Medicamentos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Inhibidores de Integrasa VIH/farmacología , Células Hep G2 , Humanos , Proteínas Klotho , Lopinavir/farmacología , Maraviroc/farmacología , Obesidad/patología , Estrés Oxidativo/efectos de los fármacos , Inhibidores de Proteasas/farmacología , Quinolonas/farmacología , Inhibidores de la Transcriptasa Inversa/farmacología , Ritonavir/farmacología , Tapsigargina/farmacología , Tunicamicina/farmacologíaRESUMEN
Calcium sensing receptor (CaSR) activates the NLRP3 inflammasome with consequences on homeostatic responses. However, little is known about how this process is orchestrated. Since proteolysis of critical regulators of NLRP3 inflammasome contribute to its activation, we aimed to understand how CaSR stimulates proteolytic pathways to activate the NLRP3 inflammasome. We found that proteasome and lysosome-dependent mechanisms are activated by CaSR to promote the degradation of important regulators of NLRP inflammasome. The pathway involves Gαq/PLC/PKC and Gßγ/PI3K signaling cascades and IRAK1 ubiquitination. In addition, CaSR stimulates Hsp70 expression activating a chaperone-assisted protein degradation that dictates the fate of ASC, NLRP3 (NOD-like receptor family protein 3), IRAK1 and TRAF6 proteins, turning on the NLRP3 inflammasome. In response to CaSR signaling, these proteins are degraded through the combination of CUPS (chaperone-assisted ubiquitin proteasome pathway) and CAEMI (chaperone-assisted endosomal microautophagy) systems being integrated by autophagosomes (chaperone-assisted macroautophagy, CAMA), as indicated by LC3-II, a classical marker for autophagy, that is induced in the process. Furthermore, CaSR triggers the proteolytic cleavage of pro-IL-1ß (IL-1ß, 31â¯kDa) into mature IL-1ß (IL-1ß, 17â¯kDa), via the proteasome. Taken together, our results indicate that CaSR promotes NLRP3 inflammasome activation and proteolytic maturation of IL-1ß by inducing CUPS and CAEMI, chaperone-assisted degradation pathways. Overall, these results support the inclusion of CaSR as an activator of homeostasis-altering molecular processes.
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Proteínas HSP70 de Choque Térmico/metabolismo , Inflamasomas/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Receptores Sensibles al Calcio/metabolismo , Células Cultivadas , Células HEK293 , HumanosRESUMEN
The physiological regulation of hepatic glutathione efflux by catecholamines is poorly understood. The purpose of this work was to review the role of adrenergic receptors (AR) on total glutathione (GT) efflux in rat liver. Two models were used: isolated hepatocytes and perfused livers. In hepatocytes 10⯵M adrenaline (Adr), but not isoproterenol (Iso) a ß-AR agonist, or phenylephrine (Phe) an α1-AR agonist, (in a Krebs-Henseleit buffer (KHB) enriched with Ca2+ and some aminoacids) increased in 13% GT efflux. In livers perfused with KHB, Adr or Iso at 1 µmolar doses (but not Phe) stimulated 11-fold initial velocity of GT release, but only during the first 2â¯min of perfusion. This immediate response progressively disappeared during the following 15â¯min of perfusion. A second phase of GT efflux, observed between 2 and 14â¯min of perfusion, mimics the one reported earlier in isolated hepatocytes. The ED50 for Adr and Iso activation are in the range of 320â¯nM and 10â¯nM, respectively. Iso-mediated GT release requires Ca2+ to work, and was prevented by H89, glibenclamide, cystic fibrosis transmembrane regulator (CFTR) antibodies, and a direct CFTR inhibitor. This short-lived GT release system is associated to PKA activation and probably operates through CFTR.
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Glutatión/metabolismo , Hepatocitos/metabolismo , Hígado/metabolismo , Receptores Adrenérgicos beta/metabolismo , Agonistas de Receptores Adrenérgicos alfa 1/farmacología , Agonistas Adrenérgicos beta/farmacología , Animales , Hepatocitos/citología , Isoproterenol/farmacología , Hígado/citología , Masculino , Fenilefrina/farmacología , Ratas , Ratas Wistar , Receptores Adrenérgicos alfa 1/metabolismoRESUMEN
AIMS/HYPOTHESIS: Adipocyte lipopolysaccharide-binding protein (LBP) biosynthesis is associated with obesity-induced adipose tissue dysfunction. Our purpose was to study the role of LBP in regulating the browning of adipose tissue. METHODS: Adult mice were maintained at 4°C for 3 weeks or treated with the ß3-adrenergic agonist, CL316,243, for 1 week to induce the browning of white fat. Precursor cells from brown and white adipose tissues were cultured under differentiation-inducing conditions to yield brown and beige/brite adipocytes, respectively. In vitro, Lbp was knocked down in 3T3-L1 adipocytes, and cells were treated with recombinant LBP or co-cultured in transwells with control 3T3-L1 adipocytes. Wild-type and Lbp-null mice, fed a standard or high fat diet (HFD) for 15 weeks, were also used in investigations. In humans, subcutaneous and visceral adipose tissue samples were obtained from a cohort of morbidly obese participants. RESULTS: The induction of white fat browning by exposure of mice to cold or CL316,243 treatment was strongly associated with decreased Lbp mRNA expression in white adipose tissue. The acquisition of the beige/brite phenotype in cultured cells was associated with downregulation of Lbp. Moreover, silencing of Lbp induced the expression of brown fat-related genes in adipocytes, whereas LBP treatment reversed this effect. Lbp-null mice exhibited the spontaneous induction of subcutaneous adipose tissue browning, as evidenced by a remarkable increase in Ucp1 and Dio2 gene expression and the appearance of multivacuolar adipocyte clusters. The amount of brown adipose tissue, and brown adipose tissue activity were also increased in Lbp-null mice. These changes were associated with decreased weight gain in Lbp-null mice and protection against HFD-induced inflammatory responses, as shown by reduced IL-6 levels. However, rather than improving glucose homeostasis, these effects led to glucose intolerance and insulin resistance. CONCLUSIONS/INTERPRETATION: LBP is identified as a negative regulator of the browning process, which is likely to contribute to the obesity-promoting action of LBP. The deleterious metabolic effects of LBP deletion are compatible with the concept that the appropriate regulation of inflammatory pathways is necessary for a healthy systemic metabolic profile, regardless of body weight regulation.
Asunto(s)
Proteínas de Fase Aguda/metabolismo , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Proteínas Portadoras/metabolismo , Glicoproteínas de Membrana/metabolismo , Obesidad Mórbida/metabolismo , Células 3T3-L1 , Proteínas de Fase Aguda/genética , Animales , Western Blotting , Proteínas Portadoras/genética , Células Cultivadas , Técnicas de Cocultivo , Dieta Alta en Grasa/efectos adversos , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Yoduro Peroxidasa/genética , Yoduro Peroxidasa/metabolismo , Glicoproteínas de Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad Mórbida/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Sirtuina 3/genética , Sirtuina 3/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo , Yodotironina Deyodinasa Tipo IIRESUMEN
Tissue inhibitors of metalloproteases (TIMPs) are multifunctional proteins that inhibit matrix metalloproteases (MMPs). The latest described member of the family, TIMP-4, is expressed mainly in adipose tissue, with detectable levels in the brain and heart. Besides its high expression in fat, the role of this inhibitor in adipose tissue is unknown. In order to study the role of TIMP-4 during adipogenesis in vitro, 3T3-L1 cells were stably transfected with a TIMP-4 specific shRNA or a control shRNA. Unexpectedly, upon TIMP-4 knockdown, 3T3-L1 cells differentiated faster into mature adipocytes. To get better insight of TIMP-4's role in adipogenesis, microarray expression analyses were performed. Network enrichment analyses uncovered 25 significant upstream signaling pathways, among which the NFκB cascade was found. Previous works have shown that NFκB is a key regulator of adipogenesis. In accordance, we found that TIMP-4 knockdown decreased NFκB activity during adipogenesis. The present work suggests that TIMP-4 might act as a negative regulator of adipogenesis through NFκB cascade modulation.