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1.
Front Immunol ; 14: 1168252, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37409123

RESUMEN

TLR Agonists have promising activity in preclinical models of viral infection and cancer. However, clinical use is only in topical application. Systemic uses of TLR-ligands such as Resiquimod, have failed due to adverse effects that limited dose and thus, efficacy. This issue could be related to pharmacokinetic properties that include fast elimination leading to low AUC with simultaneously high cmax at relevant doses. The high cmax is associated with a sharp, poorly tolerated cytokine pulse, suggesting that a compound with a higher AUC/cmax-ratio could provide a more sustained and tolerable immune activation. Our approach was to design TLR7/8-agonist Imidazoquinolines intended to partition to endosomes via acid trapping using a macrolide-carrier. This can potentially extend pharmacokinetics and simultaneously direct the compounds to the target compartment. The compounds have hTLR7/8-agonist activity (EC50 of the most active compound in cellular assays: 75-120 nM hTLR7, 2.8-3.1 µM hTLR8) and maximal hTLR7 activation between 40 and 80% of Resiquimod. The lead candidates induce secretion of IFNα from human Leukocytes in the same range as Resiquimod but induce at least 10-fold less TNFα in this system, consistent with a higher specificity for human TLR7. This pattern was reproduced in vivo in a murine system, where small molecules are thought not to activate TLR8. We found that Imidazoquinolines conjugated to a macrolide or, substances carrying an unlinked terminal secondary amine, had longer exposure compared with Resiquimod. The kinetics of pro-inflammatory cytokine release for these substances in vivo were slower and more extended (for comparable AUCs, approximately half-maximal plasma concentrations). Maximal IFNα plasma levels were reached 4 h post application. Resiquimod-treated groups had by then returned to baseline from a peak at 1 h. We propose that the characteristic cytokine profile is likely a consequence of altered pharmacokinetics and, potentially, enhanced endosomal tropism of the novel substances. In particular, our substances are designed to partition to cellular compartments where the target receptor and a distinct combination of signaling molecules relevant to IFNα-release are located. These properties could address the tolerability issues of TLR7/8 ligands and provide insight into approaches to fine-tune the outcomes of TLR7/8 activation by small molecules.


Asunto(s)
Receptor Toll-Like 7 , Factor de Necrosis Tumoral alfa , Humanos , Animales , Ratones , Ligandos , Interferón-alfa , Citocinas , Adyuvantes Inmunológicos , Macrólidos
2.
Lancet Reg Health Eur ; 31: 100656, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37303945

RESUMEN

Background: Low rates of postnatal retention in HIV care and viral suppression have been reported in women living with HIV (WLWH) despite viral suppression at delivery. At the same time, postpartum follow-up is of crucial importance in light of the increasing support offered in many resource-rich countries including Switzerland to WLWH choosing to breastfeed their infant, if optimal scenario criteria are met. Methods: We longitudinally investigated retention in HIV care, viral suppression, and infant follow-up in a prospective multicentre HIV cohort study of WLWH in the optimal scenario who had a live birth between January 2000 and December 2018. Risk factors for adverse outcomes in the first year postpartum were assessed using logistic and proportional hazard models. Findings: Overall, WLWH were retained in HIV care for at least six months after 94.2% of the deliveries (694/737). Late start of combination antiretroviral therapy (cART) during the third trimester was found to be the main risk factor for failure of retention in HIV care (crude odds ratio [OR] 3.91; 95% confidence interval [CI], 1.50-10.22; p = 0.005). Among mothers on cART until at least one year after delivery, 4.4% (26/591) experienced viral failure, with illicit drugs use being the most important risk factor (hazard ratio [HR], 13.2; 95% CI, 2.35-73.6; p = 0.003). The main risk factors for not following the recommendations regarding infant follow-up was maternal depression (OR, 3.52; 95% CI, 1.18-10.52; p = 0.024). Interpretation: Although the results are reassuring, several modifiable risk factors for adverse postpartum outcome, such as late treatment initiation and depression, were identified. These factors should be addressed in HIV care of all WLWH, especially those opting to breastfeed in resource-rich countries. Funding: This study has been financed within the framework of the Swiss HIV Cohort Study, supported by the Swiss National Science Foundation (grant #201369), by SHCS project 850 and by the SHCS research foundation.

3.
Inflammopharmacology ; 31(2): 799-812, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36943539

RESUMEN

Topical imiquimod based creams are indicated as immune stimulants for papillomas and various skin neoplasms. Imiquimod is considered a TLR7 ligand. These creams are also used in research to induce skin inflammation in mice as a model for psoriasis. We observed that this inflammatory response was not strictly imiquimod dependent and we set out to establish which components drive the proinflammatory effects. To this end, we examined the induction response in a BALB/cJRj mouse model, in which 50 mg of cream is applied to 2 cm2 of skin (125 mg/kg imiquimod-5% W/V, and/or 625 mg/kg isostearic acid-25% W/V). Comparing cream formulations containing isostearic acid, imiquimod and the combination, we observed that isostearic acid causes skin inflammation within 2 days, whereas imiquimod requires up to 5 days for initial signs. Isostearic acid activated an inflammasome response, stimulated release of proinflammatory cytokines and upregulated the IL-23/17 axis. Animals treated with isostearic acid had enlarged livers (+ 40% weight), which was not observed with imiquimod alone. Imiquimod was readily metabolized and cleared from plasma and liver, but was maintained at high levels in the skin throughout the body (200 mM at area of application; 200 µM in untreated skin). Imiquimod application was associated with splenomegaly, cytokine induction/release and initial body weight loss over 3 days. Despite high imiquimod skin levels throughout the animal, inflammation was only apparent in the treated areas and was less severe than in isostearic acid groups. As the concentrations in these areas are well above the 10 µM required for TLR7 responses in vitro, there is an implication that skin inflammation following imiquimod is due to effects other than TLR7 agonism (e.g., adenosine receptor agonism). In brain, isostearic caused no major changes in cytokine expression while imiquimod alone sightly stimulated expression of IL-1ß and CCL9. However, the combination of both caused brain induction of CCL3, -9, CXCL10, -13, IL-1ß and TNFα. The implication of these data is that isostearic acid facilitates the entry of imiquimod or peripherally secreted cytokines into the brain. Our data suggest that psoriaform skin responses in mice are more driven by isostearic acid, than generally reported and that the dose and route used in the model, leads to profound systemic effects, which may complicate the interpretation of drug effects in this model.


Asunto(s)
Dermatitis , Receptor Toll-Like 7 , Animales , Ratones , Imiquimod/metabolismo , Receptor Toll-Like 7/metabolismo , Piel/metabolismo , Citocinas/metabolismo , Dermatitis/metabolismo , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Modelos Animales de Enfermedad , Ratones Endogámicos BALB C
4.
Artif Organs ; 47(8): 1309-1318, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36995348

RESUMEN

BACKGROUND: Preeclampsia remains one of the most serious complications of pregnancy. Effective therapies are yet to be developed. Recent research has identified an imbalance of angiogenic and antiangiogenic factors as a root cause of preeclampsia. In particular, soluble fms-like tyrosine kinase-1 (sFlt-1) has been shown to bind the angiogenic factors vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), reducing blood vessel growth. Increasing preclinical and clinical evidence suggests that removal of the sFlt-1 protein may benefit patients with early onset preeclampsia. sFlt-1 may be removed by conventional blood purification techniques, such as therapeutic plasma exchange (TPE) and dextran sulfate apheresis (DSA), or emerging technologies, including extracorporeal magnetic blood purification (MBP). METHODS: We compare the performance and selectivity of TPE, DSA, and MBP for the therapeutic removal of sFlt-1. For MPB, we employ magnetic nanoparticles functionalized with either sFlt-1 antibodies or the sFlt-1-binding partner, vascular endothelial growth factor (VEGF). RESULTS: We demonstrate that sFlt-1 removal by MBP is feasible and significantly more selective than TPE and DSA at comparable sFlt-1 removal efficiencies (MBP 96%, TPE 92%, DSA 78%). During both TPE and DSA, complement factors (incl. C3c and C4) are depleted to a considerable extent (-90% for TPE, -55% for DSA), while in MBP, complement factor concentrations remain unaltered. We further demonstrate that the removal efficacy of sFlt-1 in the MBP approach is strongly dependent on the nanoparticle type and dose and can be optimized to reach clinically feasible throughputs. CONCLUSIONS: Taken together, the highly selective removal of sFlt-1 and potential other disease-causing factors by extracorporeal magnetic blood purification may offer new prospects for preeclamptic patients.


Asunto(s)
Eliminación de Componentes Sanguíneos , Preeclampsia , Embarazo , Humanos , Femenino , Factor A de Crecimiento Endotelial Vascular , Preeclampsia/terapia , Intercambio Plasmático , Factor de Crecimiento Placentario , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Sulfato de Dextran , Eliminación de Componentes Sanguíneos/métodos , Fenómenos Magnéticos
6.
Front Med (Lausanne) ; 9: 857529, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35433726

RESUMEN

Preeclampsia is one of the most dangerous diseases in pregnancy. Because of the hypertensive nature of preeclampsia, placental calcifications are believed to be a predictor for its occurrence, analogous to their role in cardiovascular diseases. However, the prevalence and the relevance of calcifications for the clinical outcome with respect to preeclampsia remains controversial. In addition, the role of other inorganic components present in the placental tissue in the development of preeclampsia has rarely been investigated. In this work, we therefore characterized inorganic constituents in placental tissue in groups of both normotensive and preeclamptic patients (N = 20 each) using a multi-scale and multi-modal approach. Examinations included elemental analysis (metallomics), sonography, computed tomography (CT), histology, scanning electron microscopy, X-ray fluorescence and energy dispersive X-ray spectroscopy. Our data show that tissue contents of several heavy metals (Al, Cd, Ni, Co, Mn, Pb, and As) were elevated whereas the Rb content was decreased in preeclamptic compared to normotensive placentae. However, the median mineral content (Ca, P, Mg, Na, K) was remarkably comparable between the two groups and CT showed lower calcified volumes and fewer crystalline deposits in preeclamptic placentae. Electron microscopy investigations revealed four distinct types of calcifications, all predominantly composed of calcium, phosphorus and oxygen with variable contents of magnesium in tissues of both maternal and fetal origin in both preeclamptic and normotensive placentae. In conclusion our study suggests that heavy metals, combined with other factors, can be associated with the development of preeclampsia, however, with no obvious correlation between calcifications and preeclampsia.

7.
BMJ Case Rep ; 15(4)2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35459654

RESUMEN

The case presented here shows the rare diagnosis of fetal otocephaly with lethal prognosis due to impossible airway management after birth. Otocephaly is characterised by fetal agnathia, microstomia and synotia. As in our case, otocephaly is usually not recognised until the third trimester and leads to challenging clinical situations and decision making.A woman in her 30s presented to our tertiary hospital at 27 weeks of gestation because of an unexplained polyhydramnios. 3D imaging illustrated the complex syndrome of otocephaly and helped understand the present disease patterns. After premature birth, palliative care was agreed on and the newborn was able to pass away peacefully in the arms of his parents.We recommend the implementation of 3D imaging into routine scans for the assessment of the fetal face and ears, especially in situations of unexplained polyhydramnios.


Asunto(s)
Anomalías Craneofaciales , Anomalías Maxilomandibulares , Polihidramnios , Femenino , Humanos , Imagenología Tridimensional , Recién Nacido , Polihidramnios/diagnóstico por imagen , Embarazo , Diagnóstico Prenatal , Ultrasonografía Prenatal/métodos
8.
BMC Pregnancy Childbirth ; 22(1): 355, 2022 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-35461218

RESUMEN

OBJECTIVE: The aim of this study was to investigate guidelines on preterm birth, analyze decision-criteria, and to identify consensus and discrepancies among these guidelines. DESIGN: Objective consensus analysis of guidelines. SAMPLE: Ten international guidelines on preterm birth. METHODS: Relevant decision criteria were singleton vs. twin pregnancy, history, cervical length, and cervical surgery / trauma or Mullerian anomaly. Eight treatment recommendations were extracted. For each decision-making criteria the most commonly recommended treatment was identified, and the level of consensus was evaluated. MAIN OUTCOME MEASURES: Consensus and Discrepancies among recommendations. RESULTS: In a case of singleton pregnancies with no history of preterm birth and shortened cervix, most guidelines recommend progesterone. In singleton pregnancies with a positive history and shortened cervix, all guidelines recommend a cerclage as an option, alternative or conjunct to progesterone. The majority of the guidelines advise against treatment in twin pregnancies. CONCLUSIONS: A shortened cervix and a history of preterm birth are relevant in singleton pregnancies. In twins, most guidelines recommend no active treatment. Among international guidelines a shortened cervix and a history of preterm birth are relevant in singleton pregnancies. With no history of preterm birth and with a shortened cervix most guidelines recommend progesterone treatment.


Asunto(s)
Cerclaje Cervical , Nacimiento Prematuro , Cuello del Útero/diagnóstico por imagen , Cuello del Útero/cirugía , Femenino , Humanos , Recién Nacido , Pesarios , Embarazo , Embarazo Gemelar , Nacimiento Prematuro/prevención & control , Progesterona/uso terapéutico
9.
Neonatology ; 118(1): 116-121, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33472211

RESUMEN

BACKGROUND: Newborns delivered by elective cesarean section (CS) are at higher respiratory risk than those delivered vaginally or by CS proceeded by labor (secondary CS). The oxytocin challenge test (OCT) induces uterine contractions that trigger the release of fetal hormones regulating lung fluid clearance during transition from the uterine to an air-breathing environment. OBJECTIVES: The aim is to summarize current evidence and outline the Lacarus trial protocol. METHODS: Literature review informed the design of a randomized placebo-controlled multicenter trial of OCT preceding elective CS in 1,450 women with a singleton pregnancy due for CS at >35 weeks gestation, without preceding contractions, rupture of the membranes, or antenatal steroids. OCT comprises the infusion of oxytocin 5 IU/500 mL Ringer lactate at a rate of 12 mL/h, doubling every 10 min until inducing 5 uterine contractions per 15-min interval. The primary endpoint is the occurrence of neonatal respiratory morbidity within 24 h after birth. Secondary endpoints include biochemical and physiological parameters of fetal and maternal well-being, such as breastfeeding rate and fetal plasma copeptin concentrations. CONCLUSION: This is the first trial to test the hypothesis that oxytocin-induced contractions before elective CS is a promising application of physiologic principles gleaned from natural birth to improve neonatal and maternal outcomes.


Asunto(s)
Cesárea , Trabajo de Parto Inducido , Femenino , Edad Gestacional , Humanos , Recién Nacido , Oxitocina , Embarazo
11.
Analyst ; 144(23): 6850-6857, 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-31591608

RESUMEN

Despite its crucial role, the placenta is the least understood human organ. Recent clinical studies indicate a direct association between placental calcification and maternal and offspring health. This study reveals distinct characteristics of minerals formed during gestational ageing using cutting-edge nano-analytical characterization and paves the way for investigations focused on the identification of potential markers for disease risks in a clinical setting based on atypical placental mineral fingerprints.


Asunto(s)
Calcificación Fisiológica/fisiología , Minerales/análisis , Placenta/metabolismo , Animales , Gatos , Perros , Femenino , Caballos , Humanos , Microscopía Electrónica de Rastreo , Minerales/química , Minerales/metabolismo , Placenta/ultraestructura , Embarazo , Conejos , Análisis Espectral , Tomografía Computarizada por Rayos X
12.
J Am Heart Assoc ; 6(10)2017 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-29066440

RESUMEN

BACKGROUND: Respiratory muscle weakness contributes to exercise intolerance in patients with heart failure with a preserved ejection fraction (HFpEF)-a condition characterized by multiple comorbidities with few proven treatments. We aimed, therefore, to provide novel insight into the underlying diaphragmatic alterations that occur in HFpEF by using an obese cardiometabolic rat model and further assessed whether exercise training performed only after the development of overt HFpEF could reverse impairments. METHODS AND RESULTS: Obese ZSF1 rats (n=12) were compared with their lean controls (n=8) at 20 weeks, with 3 additional groups of obese ZSF1 rats compared at 28 weeks following 8 weeks of either sedentary behavior (n=13), high-intensity interval training (n=11), or moderate-continuous training (n=11). Obese rats developed an obvious HFpEF phenotype at 20 and 28 weeks. In the diaphragm at 20 weeks, HFpEF induced a shift towards an oxidative phenotype and a fiber hypertrophy paralleled by a lower protein expression in MuRF1 and MuRF2, yet mitochondrial and contractile functional impairments were observed. At 28 weeks, neither the exercise training regimen of high-intensity interval training or moderate-continuous training reversed any of the diaphragm alterations induced by HFpEF. CONCLUSIONS: This study, using a well-characterized rat model of HFpEF underpinned by multiple comorbidities and exercise intolerance (ie, one that closely resembles the patient phenotype), provides evidence that diaphragm alterations and dysfunction induced in overt HFpEF are not reversed following 8 weeks of aerobic exercise training. As such, whether alternative therapeutic interventions are required to treat respiratory muscle weakness in HFpEF warrants further investigation.


Asunto(s)
Diafragma/fisiopatología , Tolerancia al Ejercicio , Insuficiencia Cardíaca/terapia , Entrenamiento de Intervalos de Alta Intensidad , Debilidad Muscular , Obesidad/terapia , Volumen Sistólico , Función Ventricular Izquierda , Animales , Diafragma/metabolismo , Modelos Animales de Enfermedad , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/fisiopatología , Mitocondrias Musculares/metabolismo , Mitocondrias Musculares/patología , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patología , Proteínas Musculares/metabolismo , Obesidad/complicaciones , Obesidad/metabolismo , Obesidad/fisiopatología , Oxidación-Reducción , Fenotipo , Ratas Zucker , Factores de Tiempo , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
13.
J Cachexia Sarcopenia Muscle ; 8(6): 939-953, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28887874

RESUMEN

BACKGROUND: Muscle ring finger 1 (MuRF1) is a muscle-specific ubiquitin E3 ligase activated during clinical conditions associated with skeletal muscle wasting. Yet, there remains a paucity of therapeutic interventions that directly inhibit MuRF1 function, particularly in vivo. The current study, therefore, developed a novel compound targeting the central coiled coil domain of MuRF1 to inhibit muscle wasting in cardiac cachexia. METHODS: We identified small molecules that interfere with the MuRF1-titin interaction from a 130 000 compound screen based on Alpha Technology. A subset of nine prioritized compounds were synthesized and administrated during conditions of muscle wasting, that is, to C2C12 muscle cells treated with dexamethasone and to mice treated with monocrotaline to induce cardiac cachexia. RESULTS: The nine selected compounds inhibited MuRF1-titin complexation with IC50 values <25 µM, of which three were found to also inhibit MuRF1 E3 ligase activity, with one further showing low toxicity on cultured myotubes. This last compound, EMBL chemical core ID#704946, also prevented atrophy in myotubes induced by dexamethasone and attenuated fibre atrophy and contractile dysfunction in mice during cardiac cachexia. Proteomic and western blot analyses showed that stress pathways were attenuated by ID#704946 treatment, including down-regulation of MuRF1 and normalization of proteins associated with apoptosis (BAX) and protein synthesis (elF2B-delta). Furthermore, actin ubiquitinylation and proteasome activity was attenuated. CONCLUSIONS: We identified a novel compound directed to MuRF1's central myofibrillar protein recognition domain. This compound attenuated in vivo muscle wasting and contractile dysfunction in cardiac cachexia by protecting de novo protein synthesis and by down-regulating apoptosis and ubiquitin-proteasome-dependent proteolysis.


Asunto(s)
Caquexia/patología , Caquexia/fisiopatología , Corazón/fisiopatología , Proteínas Musculares/antagonistas & inhibidores , Atrofia Muscular/patología , Atrofia Muscular/fisiopatología , Miocardio/patología , Proteínas de Motivos Tripartitos/antagonistas & inhibidores , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , Animales , Biomarcadores , Caquexia/tratamiento farmacológico , Caquexia/etiología , Línea Celular , Dexametasona/farmacología , Descubrimiento de Drogas , Humanos , Ratones , Contracción Muscular/efectos de los fármacos , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/etiología , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Transducción de Señal
14.
Med Sci Sports Exerc ; 49(5): 879-887, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28009790

RESUMEN

PURPOSE: Cigarette smoking is the main risk factor for chronic obstructive pulmonary disease and emphysema. However, evidence on the extrapulmonary effects of smoke exposure that precede lung impairments remains unclear at present, as are data on nonpharmacological treatments such as exercise training. METHODS: Three groups of mice, including control (n = 10), smoking (n = 10), and smoking with 6 wk of high-intensity interval treadmill running (n = 11), were exposed to 20 wk of fresh air or whole-body cigarette smoke. Exercise capacity (peak oxygen uptake) and lung destruction (histology) were subsequently measured, whereas the heart, peripheral endothelium (aorta), and respiratory (diaphragm) and limb (extensor digitorum longus and soleus) skeletal muscles were assessed for in vivo and in vitro function, in situ mitochondrial respiration, and molecular alterations. RESULTS: Smoking reduced body weight by 26% (P < 0.05) without overt airway destruction (P > 0.05). Smoking impaired exercise capacity by 15% while inducing right ventricular dysfunction by ~20%, endothelial dysfunction by ~20%, and diaphragm muscle weakness by ~15% (all P < 0.05), but these were either attenuated or reversed by exercise training (P < 0.05). Compared with controls, smoking mice had normal limb muscle and mitochondrial function (cardiac and skeletal muscle fibers); however, diaphragm measures of oxidative stress and protein degradation were increased by 111% and 65%, respectively (P < 0.05), but these were attenuated by exercise training (P < 0.05). CONCLUSIONS: Prolonged cigarette smoking reduced exercise capacity concomitant with functional impairments to the heart, peripheral endothelium, and respiratory muscle that preceded the development of overt emphysema. However, high-intensity exercise training was able to reverse these smoke-induced extrapulmonary impairments.


Asunto(s)
Diafragma/fisiopatología , Endotelio Vascular/fisiopatología , Tolerancia al Ejercicio/fisiología , Pulmón/fisiopatología , Músculo Esquelético/fisiopatología , Condicionamiento Físico Animal/fisiología , Fumar/efectos adversos , Animales , Peso Corporal , Femenino , Extremidad Inferior/fisiopatología , Pulmón/patología , Ratones , Mitocondrias Musculares/fisiología , Modelos Animales , Consumo de Oxígeno/fisiología , Condicionamiento Físico Animal/métodos , Disfunción Ventricular Derecha/fisiopatología
15.
FASEB J ; 31(1): 60-71, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27650398

RESUMEN

Hypertension is a key risk factor for heart failure, with the latter characterized by diaphragm muscle weakness that is mediated in part by increased oxidative stress. In the present study, we used a deoxycorticosterone acetate (DOCA)-salt mouse model to determine whether hypertension could independently induce diaphragm dysfunction and further investigated the effects of high-intensity interval training (HIIT). Sham-treated (n = 11), DOCA-salt-treated (n = 11), and DOCA-salt+HIIT-treated (n = 15) mice were studied over 4 wk. Diaphragm contractile function, protein expression, enzyme activity, and fiber cross-sectional area and type were subsequently determined. Elevated blood pressure confirmed hypertension in DOCA-salt mice independent of HIIT (P < 0.05). Diaphragm forces were impaired by ∼15-20% in DOCA-salt vs. sham-treated mice (P < 0.05), but this effect was prevented after HIIT. Myosin heavy chain (MyHC) protein expression tended to decrease (∼30%; P = 0.06) in DOCA-salt vs. sham- and DOCA-salt+HIIT mice, whereas oxidative stress increased (P < 0.05). Enzyme activity of NADPH oxidase was higher, but superoxide dismutase was lower, with MyHC oxidation elevated by ∼50%. HIIT further prevented direct oxidant-mediated diaphragm contractile dysfunction (P < 0.05) after a 30 min exposure to H2O-2 (1 mM). Our data suggest that hypertension induces diaphragm contractile dysfunction via an oxidant-mediated mechanism that is prevented by HIIT.-Bowen, T. S., Eisenkolb, S., Drobner, J., Fischer, T., Werner, S., Linke, A., Mangner, N., Schuler, G., Adams, V. High-intensity interval training prevents oxidant-mediated diaphragm muscle weakness in hypertensive mice.


Asunto(s)
Diafragma/patología , Entrenamiento de Intervalos de Alta Intensidad , Debilidad Muscular/prevención & control , Oxidantes/metabolismo , Condicionamiento Físico Animal/fisiología , Animales , Fenómenos Fisiológicos Cardiovasculares , Desoxicorticosterona/administración & dosificación , Desoxicorticosterona/farmacología , Hipertensión , Masculino , Ratones , Ratones Endogámicos C57BL , Mineralocorticoides/administración & dosificación , Mineralocorticoides/farmacología , Mitocondrias/fisiología , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Debilidad Muscular/metabolismo , Estrés Oxidativo
16.
Cardiol Res Pract ; 2016: 2820432, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27965912

RESUMEN

Background. Endothelial dysfunction occurs in obese children and adolescent and is regarded as a key step in the development of atherosclerosis. Important components for the development of endothelial dysfunction are reduced activity of endothelial nitric oxide synthase (eNOS) and an increase in cholesterol deposition in the vessel wall, due to reduced reverse cholesterol transport (RCT) activity. High density lipoprotein (HDL) exhibits antiatherosclerotic properties including modulation of eNOS activity and cholesterol efflux capacity. Lifestyle intervention programs can modify endothelial dysfunction in obese adolescents, but their impact on HDL-mediated eNOS activation and RCT is unknown so far. Methods. Obese adolescents (15 ± 1 years, BMI > 35 kg/m2) where randomized either to an intervention group (IG, n = 8; restricted diet and exercise) or to a usual care group (UC, n = 8). At the beginning and after 10 months of treatment HDL-mediated eNOS phosphorylation and cholesterol efflux capacity were evaluated. Results. Ten months of treatment resulted in a substantial weight loss (-31%), an improvement of endothelial function, and an increase in HDL-mediated eNOS-Ser1177 phosphorylation and RCT. A correlation between change in eNOS-Ser1177 phosphorylation or RCT and change in endothelial function was noted. Conclusion. A structured lifestyle intervention program improves antiatherosclerotic HDL functions, thereby positively influencing endothelial function.

17.
Circ Heart Fail ; 9(9)2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27609832

RESUMEN

BACKGROUND: A greater understanding of the different underlying mechanisms between patients with heart failure with reduced (HFrEF) and with preserved (HFpEF) ejection fraction is urgently needed to better direct future treatment. However, although skeletal muscle impairments, potentially mediated by inflammatory cytokines, are common in both HFrEF and HFpEF, the underlying cellular and molecular alterations that exist between groups are yet to be systematically evaluated. The present study, therefore, used established animal models to compare whether alterations in skeletal muscle (limb and respiratory) were different between HFrEF and HFpEF, while further characterizing inflammatory cytokines. METHODS AND RESULTS: Rats were assigned to (1) HFrEF (ligation of the left coronary artery; n=8); (2) HFpEF (high-salt diet; n=10); (3) control (con: no intervention; n=7). Heart failure was confirmed by echocardiography and invasive measures. Soleus tissue in HFrEF, but not in HFpEF, showed a significant increase in markers of (1) muscle atrophy (ie, MuRF1, calpain, and ubiquitin proteasome); (2) oxidative stress (ie, higher nicotinamide adenine dinucleotide phosphate oxidase but lower antioxidative enzyme activities); (3) mitochondrial impairments (ie, a lower succinate dehydrogenase/lactate dehydrogenase ratio and peroxisome proliferator-activated receptor-γ coactivator-1α expression). The diaphragm remained largely unaffected between groups. Plasma concentrations of circulating cytokines were significantly increased in HFrEF for tumor necrosis factor-α, whereas interleukin-1ß and interleukin-12 were higher in HFpEF. CONCLUSIONS: Our findings suggest, for the first time, that skeletal muscle alterations are exacerbated in HFrEF compared with HFpEF, which predominantly reside in limb, rather than in respiratory, muscle. This disparity may be mediated, in part, by the different circulating inflammatory cytokines that were elevated between HFpEF and HFrEF.


Asunto(s)
Citocinas/sangre , Insuficiencia Cardíaca/sangre , Mediadores de Inflamación/sangre , Músculo Esquelético/metabolismo , Volumen Sistólico , Función Ventricular Izquierda , Animales , Diafragma/metabolismo , Modelos Animales de Enfermedad , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Interleucina-12/sangre , Interleucina-1beta/sangre , Mitocondrias Musculares/metabolismo , Músculo Esquelético/enzimología , Músculo Esquelético/patología , Atrofia Muscular/sangre , Atrofia Muscular/patología , Estrés Oxidativo , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/sangre , Regulación hacia Arriba
18.
Cardiol Res Pract ; 2016: 4826102, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27563480

RESUMEN

Background. Endothelial function is impaired in chronic heart failure (CHF). Statins upregulate endothelial NO synthase (eNOS) and improve endothelial function. Recent studies demonstrated that HDL stimulates NO production due to eNOS phosphorylation at Ser(1177), dephosphorylation at Thr(495), and diminished phosphorylation of PKC-ßII at Ser(660). The aim of this study was to elucidate the impact of rosuvastatin on HDL mediated eNOS and PKC-ßII phosphorylation and its relation to endothelial function. Methods. 18 CHF patients were randomized to 12 weeks of rosuvastatin or placebo. At baseline, 12 weeks, and 4 weeks after treatment cessation we determined lipid levels and isolated HDL. Human aortic endothelial cells (HAEC) were incubated with isolated HDL and phosphorylation of eNOS and PKC-ßII was evaluated. Flow-mediated dilatation (FMD) was measured at the radial artery. Results. Rosuvastatin improved FMD significantly. This effect was blunted after treatment cessation. LDL plasma levels were reduced after rosuvastatin treatment whereas drug withdrawal resulted in significant increase. HDL levels remained unaffected. Incubation of HAEC with HDL had no impact on phosphorylation of eNOS or PKC-ßII. Conclusion. HDL mediated eNOS and PKC-ßII phosphorylation levels in endothelial cells do not change with rosuvastatin in CHF patients and do not mediate the marked improvement in endothelial function.

19.
Med Sci Sports Exerc ; 48(11): 2118-2124, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27327028

RESUMEN

PURPOSE: Patient studies have demonstrated the efficacy of exercise training in attenuating respiratory muscle weakness in chronic heart failure (HF), yet direct assessment of muscle fiber contractile function together with data on the underlying intracellular mechanisms remains elusive. The present study, therefore, used a mouse model of HF to assess whether exercise training could prevent diaphragm contractile fiber dysfunction by potentially mediating the complex interplay between intracellular oxidative stress and proteolysis. METHODS: Mice underwent sham operation (n = 10) or a ligation of the left coronary artery and were randomized to sedentary HF (n = 10) or HF with aerobic exercise training (HF + AET; n = 10). Ten weeks later, echocardiography and histological analyses confirmed HF. RESULTS: In vitro diaphragm fiber bundles demonstrated contractile dysfunction in sedentary HF compared with sham mice that was prevented by AET, with maximal force 21.0 ± 0.7 versus 26.7 ± 1.4 and 25.4 ± 1.4 N·cm, respectively (P < 0.05). Xanthine oxidase enzyme activity and MuRF1 protein expression, markers of oxidative stress and protein degradation, were ~20% and ~70% higher in sedentary HF compared with sham mice (P < 0.05) but were not different when compared with the HF + AET group. Oxidative modifications to numerous contractile proteins (i.e., actin and creatine kinase) and markers of proteolysis (i.e., proteasome and calpain activity) were elevated in sedentary HF compared with HF + AET mice (P < 0.05); however, these indices were not significantly different between sedentary HF and sham mice. Antioxidative enzyme activities were also not different between groups. CONCLUSION: Our findings demonstrate that AET can protect against diaphragm contractile fiber dysfunction induced by HF, but it remains unclear whether alterations in oxidative stress and/or protein degradation are primarily responsible.


Asunto(s)
Diafragma/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Contracción Muscular/fisiología , Condicionamiento Físico Animal , Animales , Proteínas Contráctiles/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones Endogámicos C57BL , Fibras Musculares Esqueléticas/enzimología , Fibras Musculares Esqueléticas/fisiología , Proteínas Musculares/metabolismo , Estrés Oxidativo , Proteolisis , Distribución Aleatoria , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Xantina Oxidasa/metabolismo
20.
J Appl Physiol (1985) ; 119(6): 745-52, 2015 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26229002

RESUMEN

Heart failure patients with preserved left ventricular ejection fraction (HFpEF) have endothelial dysfunction, but the underlying molecular mechanisms remain unknown. In addition, whether exercise training improves endothelial function in HFpEF is still controversial. The present study therefore aimed to determine the functional and molecular alterations in the endothelium associated with HFpEF, while further assessing the effects of high-intensity interval training (HIT). Female Dahl salt-sensitive rats were randomized for 28 wk into the following groups: 1) control: fed 0.3% NaCl; 2) HFpEF: fed 8% NaCl; and 3) HFpEF + HIT: animals fed 8% NaCl and HIT treadmill exercise. Echocardiography and invasive hemodynamic measurements were used to assess diastolic dysfunction. Endothelial function of the aorta was measured in vitro. Expression of endothelial nitric oxide synthase (eNOS), nicotinamide adenine dinucleotide phosphate-oxidase [NAD(P)H oxidase], and advanced glycation end product (AGE)-modified proteins were quantified by Western blot, and zymography quantified matrix metalloproteinase (MMP) activity. In this model of HFpEF, endothelium-dependent and -independent vasodilation was impaired. However, this was prevented by HIT. In HFpEF protein expression of eNOS was reduced by 47%, but MMP-2 and MMP-9 activity was elevated by 186 and 68%. The expression of AGE-modified proteins was increased by 106%. All of these changes were prevented by HIT. Endothelial function was impaired in this model of HFpEF, which was associated with reduced expression of eNOS, increased MMP activity, and increased AGE-modified proteins. HIT was able to attenuate both these functional and molecular alterations. These findings therefore suggest HFpEF induces endothelial dysfunction, but this is reversible by HIT.


Asunto(s)
Endotelio/fisiopatología , Tolerancia al Ejercicio/fisiología , Insuficiencia Cardíaca/fisiopatología , Condicionamiento Físico Animal/fisiología , Cloruro de Sodio/metabolismo , Enfermedades Vasculares/fisiopatología , Animales , Endotelio/metabolismo , Prueba de Esfuerzo/métodos , Femenino , Insuficiencia Cardíaca/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Ratas , Ratas Endogámicas Dahl , Enfermedades Vasculares/metabolismo , Vasodilatación/fisiología
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