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Lung type 2 pneumocytes (T2Ps) and alveolar macrophages (AMs) play crucial roles in the synthesis, recycling and catabolism of surfactant material, a lipid/protein fluid essential for respiratory function. The liver X receptors (LXR), LXRα and LXRß, are transcription factors important for lipid metabolism and inflammation. While LXR activation exerts anti-inflammatory actions in lung injury caused by lipopolysaccharide (LPS) and other inflammatory stimuli, the full extent of the endogenous LXR transcriptional activity in pulmonary homeostasis is incompletely understood. Here, using mice lacking LXRα and LXRß as experimental models, we describe how the loss of LXRs causes pulmonary lipidosis, pulmonary congestion, fibrosis and chronic inflammation due to defective de novo synthesis and recycling of surfactant material by T2Ps and defective phagocytosis and degradation of excess surfactant by AMs. LXR-deficient T2Ps display aberrant lamellar bodies and decreased expression of genes encoding for surfactant proteins and enzymes involved in cholesterol, fatty acids, and phospholipid metabolism. Moreover, LXR-deficient lungs accumulate foamy AMs with aberrant expression of cholesterol and phospholipid metabolism genes. Using a house dust mite aeroallergen-induced mouse model of asthma, we show that LXR-deficient mice exhibit a more pronounced airway reactivity to a methacholine challenge and greater pulmonary infiltration, indicating an altered physiology of LXR-deficient lungs. Moreover, pretreatment with LXR agonists ameliorated the airway reactivity in WT mice sensitized to house dust mite extracts, confirming that LXR plays an important role in lung physiology and suggesting that agonist pharmacology could be used to treat inflammatory lung diseases.
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Homeostasis , Receptores X del Hígado , Macrófagos Alveolares , Neumonía , Surfactantes Pulmonares , Transducción de Señal , Animales , Receptores X del Hígado/metabolismo , Receptores X del Hígado/genética , Surfactantes Pulmonares/metabolismo , Ratones , Neumonía/metabolismo , Neumonía/patología , Macrófagos Alveolares/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Pulmón/metabolismo , Pulmón/patología , Células Epiteliales Alveolares/metabolismo , Asma/metabolismo , Asma/patología , Asma/genética , Colesterol/metabolismo , Metabolismo de los Lípidos , FagocitosisRESUMEN
BACKGROUND: High-risk Pulmonary Embolism (PE) mortality remains very high. Systemic thrombolysis is effective but carries significant complications and contraindications related to the hemorrhagic risk. Percutaneous thrombectomy using aspiration catheters may be an alternative in patients with a high bleeding risk. OBJECTIVE: This study aimed to evaluate the results of catheter-directed thrombectomy using aspiration dedicated catheters in patients with high-risk PE and absolute contraindication to systemic thrombolysis, with specific focus on procedural success, safety, and in-hospital outcomes. METHODS: A prospective study enrolled all consecutive patients diagnosed with high-risk pulmonary embolism and absolute contraindication to systemic thrombolysis, who underwent percutaneous pulmonary thrombectomy using dedicated aspiration catheters. The study documented the effectiveness and complications of the procedure, as well as patient outcomes at discharge and during the follow-up period. RESULTS: Thirteen patients underwent percutaneous pulmonary thrombectomy using aspiration dedicated catheters. The procedure was successful for all patients, resulting in hemodynamic and respiratory improvement within the first 24 h. No deaths attributable to cardiovascular or respiratory causes occurred during admission or follow-up. Furthermore, no serious adverse events or complications were reported during the procedure or hospitalization. CONCLUSIONS: Percutaneous pulmonary thrombectomy with dedicated aspiration catheters in patients with high-risk pulmonary embolism and contraindications to systemic thrombolysis was associated with excellent clinical results and low rate of complications.
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BACKGROUND AND AIMS: Cyclooxygenase-2 (COX-2) is involved in different liver diseases, but little is known about the significance of COX-2 in cholestatic injury. This study was designed to elucidate the role of COX-2 expression in hepatocytes during the pathogenesis of obstructive cholestasis. METHODS: We used genetically modified mice constitutively expressing human COX-2 in hepatocytes. Transgenic mice (hCOX-2-Tg) and their wild-type (Wt) littermates were either subjected to a mid-abdominal laparotomy or common bile duct ligation (BDL) for 2 or 5 days. Then, we explored the mechanisms underlying the role of COX-2 and its derived prostaglandins in liver function, and the synthesis and excretion of bile acids (BA) in response to cholestatic liver injury. RESULTS: After BDL, hCOX-2-Tg mice showed lower grades of hepatic necrosis and inflammation than Wt mice, in part by a reduced hepatic neutrophil recruitment associated with lower mRNA levels of pro-inflammatory cytokines. Furthermore, hCOX-2-Tg mice displayed a differential metabolic pattern of BA synthesis that led to an improved clearance after BDL-induced accumulation. In addition, an enhanced response to the BDL-induced oxidative stress and hepatic apoptosis was observed. In vitro experiments using hepatic cells that stably express hCOX-2 confirmed the cytoprotective role of prostaglandin E2 against BA toxicity. CONCLUSIONS: Taken together, our data indicate that constitutive expression of COX-2 in hepatocytes ameliorates cholestatic liver injury in mice by reducing inflammation and cell damage and by modulating BA metabolism, pointing to a role for COX-2 as a defensive response against cholestasis-derived BA accumulation and injury.
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Ácidos y Sales Biliares , Colestasis , Conducto Colédoco , Ciclooxigenasa 2 , Hepatocitos , Hígado , Ratones Transgénicos , Animales , Ciclooxigenasa 2/metabolismo , Ciclooxigenasa 2/genética , Ratones , Ligadura , Hígado/patología , Hígado/metabolismo , Ácidos y Sales Biliares/metabolismo , Colestasis/metabolismo , Hepatocitos/metabolismo , Conducto Colédoco/cirugía , Estrés Oxidativo , Apoptosis , Humanos , Modelos Animales de Enfermedad , MasculinoRESUMEN
BACKGROUND: Previous studies have documented a high rate of implantation success with the ACURATE neo2 valve, as well as a reduction in paravalvular leak (PVL) compared to its predecessor, the ACURATE neo. However, there are no studies that have reviewed and compared the long-term clinical and hemodynamic outcomes of these patients. AIMS: This study aimed to evaluate the results of the ACURATE neo transcatheter aortic valve in a real-world context, and to compare the results of the outcomes of both generations of this device (ACURATE neo and ACURATE neo2), with a specific focus on procedural success, safety, and long-term effectiveness. METHODS: A prospective study including all consecutive patients treated with the ACURATE neo device in seven hospitals was conducted (Clinical Trials Identification Number: NCT03846557). The primary endpoint consisted of a composite of adverse events, including mortality, aortic insufficiency, and other procedural complications. As the second-generation device (ACURATE neo2) replaced the ACURATE neo during the study period, hemodynamic and clinical results before admission, at 30 days, and at 1 year of follow-up were compared between the two generations. RESULTS: A total of 296 patients underwent transcatheter aortic valve implantation with the ACURATE device, with 178 patients receiving the ACURATE neo and 118 patients receiving the ACURATE neo2. In the overall population, the absence of device success occurred in 14.5%. The primary reason for the absence of device success was the presence of para-valvular regurgitation ≥ 2. There were no instances of coronary occlusions, valve embolization, annulus rupture, or procedural deaths. ACURATE neo2 was associated with a significantly higher device success rate (91.7% vs. 82%, p = 0.04), primarily due to a significantly lower rate of para-valvular regurgitation, which remained significant at 1 year. CONCLUSION: The use of ACURATE neo and neo2 transcatheter aortic valves is associated with satisfactory clinical results and an extremely low rate of complications. The ACURATE neo2 enables a significantly higher device success rate, primarily attributed to a significant reduction in the rate of PVL.
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Estenosis de la Válvula Aórtica , Válvula Aórtica , Prótesis Valvulares Cardíacas , Hemodinámica , Diseño de Prótesis , Sistema de Registros , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Válvula Aórtica/cirugía , Válvula Aórtica/fisiopatología , Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/fisiopatología , Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Complicaciones Posoperatorias , Estudios Prospectivos , Recuperación de la Función , Factores de Riesgo , España , Factores de Tiempo , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del TratamientoRESUMEN
Contrast-Induced Acute Kidney Injury (CI-AKI) remains a frequent iatrogenic condition since radiological procedures using intra-vascular iodinated contrast media (CM) are being widely administered for diagnostic and therapeutic purposes. Despite the improvement of the medical healthcare system worldwide, CI-AKI is still associated with direct short-term and indirect long-term outcomes including increased morbidity and mortality, especially in patients with underlying pre-existing renal function impairment, cardiovascular disease, or diabetes that could rapidly progress into Chronic Kidney Disease. Although the RIFLE (Risk, Injury, Failure, Loss, End-Stage Kidney Disease), AKIN (Acute Kidney Injury Network), and KDIGO (Kidney Disease Improving Global Outcomes) clinical criteria and recommendation guidelines are based on traditional "gold standard" biomarkers known as serum creatinine, glomerular filtration rate, and urinary output, new reliable serum and urinary biomarkers are still needed for an effective unified diagnostic strategy for AKI. Starting from previous and recent publications on the benefits and limitations of validated biomarkers responding to kidney injury, glomerular filtration, and inflammation among others, this review unravels the role of new emerging biomarkers used alone or in combination as reliable tools for early diagnosis and prognosis of CI-AKI, taking into account patients and procedures-risk factors towards a new clinical perspective.
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Lesión Renal Aguda , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Fallo Renal Crónico , Humanos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/diagnóstico , Riñón , Biomarcadores , Fallo Renal Crónico/complicaciones , Factores de Riesgo , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/complicaciones , CreatininaRESUMEN
Macrophages regulate essential aspects of innate immunity against pathogens. In response to microbial components, macrophages activate primary and secondary inflammatory gene programs crucial for host defense. The liver X receptors (LXRα, LXRß) are ligand-dependent nuclear receptors that direct gene expression important for cholesterol metabolism and inflammation, but little is known about the individual roles of LXRα and LXRß in antimicrobial responses. Here, the results demonstrate that induction of LXRα transcription by prolonged exposure to lipopolysaccharide (LPS) supports inflammatory gene expression in macrophages. LXRα transcription is induced by NF-κB and type-I interferon downstream of TLR4 activation. Moreover, LPS triggers a reprogramming of the LXRα cistrome that promotes cytokine and chemokine gene expression through direct LXRα binding to DNA consensus sequences within cis-regulatory regions including enhancers. LXRα-deficient macrophages present fewer binding of p65 NF-κB and reduced histone H3K27 acetylation at enhancers of secondary inflammatory response genes. Mice lacking LXRα in the hematopoietic compartment show impaired responses to bacterial endotoxin in peritonitis models, exhibiting reduced neutrophil infiltration and decreased expansion and inflammatory activation of recruited F4/80lo-MHC-IIhi peritoneal macrophages. Together, these results uncover a previously unrecognized function for LXRα-dependent transcriptional cis-activation of secondary inflammatory gene expression in macrophages and the host response to microbial ligands.
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Inflamación , Receptores X del Hígado , Macrófagos , Transcriptoma , Animales , Ratones , Modelos Animales de Enfermedad , Inflamación/genética , Inflamación/metabolismo , Lipopolisacáridos , Receptores X del Hígado/genética , Receptores X del Hígado/metabolismo , Macrófagos/metabolismo , Macrófagos/inmunología , Ratones Endogámicos C57BLRESUMEN
Nucleotide-binding oligomerization domain-like (NOD) receptors rely on the interface between immunity and metabolism. Dietary factors constitute critical players in the activation of innate immunity and modulation of the gut microbiota. The latter have been involved in worsening or improving the control and promotion of diseases such as obesity, type 2 diabetes, metabolic syndrome, diseases known as non-communicable metabolic diseases (NCDs), and the risk of developing cancer. Intracellular NODs play key coordinated actions with innate immune 'Toll-like' receptors leading to a diverse array of gene expressions that initiate inflammatory and immune responses. There has been an improvement in the understanding of the molecular and genetic implications of these receptors in, among others, such aspects as resting energy expenditure, insulin resistance, and cell proliferation. Genetic factors and polymorphisms of the receptors are determinants of the risk and severity of NCDs and cancer, and it is conceivable that dietary factors may have significant differential consequences depending on them. Host factors are difficult to influence, while environmental factors are predominant and approachable with a preventive and/or therapeutic intention in obesity, T2D, and cancer. However, beyond the recognition of the activation of NODs by peptidoglycan as its prototypical agonist, the underlying molecular response(s) and its consequences on these diseases remain ill-defined. Metabolic (re)programming is a hallmark of NCDs and cancer in which nutritional strategies might play a key role in preventing the unprecedented expansion of these diseases. A better understanding of the participation and effects of immunonutritional dietary ingredients can boost integrative knowledge fostering interdisciplinary science between nutritional precision and personalized medicine against cancer. This review summarizes the current evidence concerning the relationship(s) and consequences of NODs on immune and metabolic health.
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Trabectedin (TRB) and Lurbinectedin (LUR) are alkaloid compounds originally isolated from Ecteinascidia turbinata with proven antitumoral activity. Both molecules are structural analogues that differ on the tetrahydroisoquinoline moiety of the C subunit in TRB, which is replaced by a tetrahydro-ß-carboline in LUR. TRB is indicated for patients with relapsed ovarian cancer in combination with pegylated liposomal doxorubicin, as well as for advanced soft tissue sarcoma in adults in monotherapy. LUR was approved by the FDA in 2020 to treat metastatic small cell lung cancer. Herein, we systematically summarise the origin and structure of TRB and LUR, as well as the molecular mechanisms that they trigger to induce cell death in tumoral cells and supporting stroma cells of the tumoral microenvironment, and how these compounds regulate immune cell function and fate. Finally, the novel therapeutic venues that are currently under exploration, in combination with a plethora of different immunotherapeutic strategies or specific molecular-targeted inhibitors, are reviewed, with particular emphasis on the usage of immune checkpoint inhibitors, or other bioactive molecules that have shown synergistic effects in terms of tumour regression and ablation. These approaches intend to tackle the complexity of managing cancer patients in the context of precision medicine and the application of tailor-made strategies aiming at the reduction of undesired side effects.
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Carbolinas , Compuestos Heterocíclicos de 4 o más Anillos , Neoplasias Ováricas , Microambiente Tumoral , Adulto , Femenino , Humanos , Trabectedina , Recurrencia Local de NeoplasiaRESUMEN
The role of extracellular nucleotides as modulators of inflammation and cell stress is well established. One of the main actions of these molecules is mediated by the activation of purinergic receptors (P2) of the plasma membrane. P2 receptors can be classified according to two different structural families: P2X ionotropic ion channel receptors, and P2Y metabotropic G protein-coupled receptors. During inflammation, damaged cells release nucleotides and purinergic signaling occurs along the temporal pattern of the synthesis of pro-inflammatory and pro-resolving mediators by myeloid and lymphoid cells. In macrophages under pro-inflammatory conditions, the expression and activity of cyclooxygenase 2 significantly increases and enhances the circulating levels of prostaglandin E2 (PGE2), which exerts its effects both through specific plasma membrane receptors (EP1-EP4) and by activation of intracellular targets. Here we review the mechanisms involved in the crosstalk between PGE2 and P2Y receptors on macrophages, which is dependent on several isoforms of protein kinase C and protein kinase D1. Due to this crosstalk, a P2Y-dependent increase in calcium is blunted by PGE2 whereas, under these conditions, macrophages exhibit reduced migratory capacity along with enhanced phagocytosis, which contributes to the modulation of the inflammatory response and tissue repair.
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Inflamación , Prostaglandina-Endoperóxido Sintasas , Humanos , Prostaglandina-Endoperóxido Sintasas/metabolismo , Inflamación/metabolismo , Nucleótidos/metabolismo , Macrófagos/metabolismo , Receptores Purinérgicos/metabolismoRESUMEN
In the aftermath of tissue injury or infection, an efficient resolution mechanism is crucial to allow tissue healing and preserve appropriate organ functioning. Pro-resolving bioactive lipids prevent uncontrolled inflammation and its consequences. Among these mediators, lipoxins were the first described and their pro-resolving actions have been mainly described in immune cells. They exert their actions mostly through formyl-peptide receptor 2 (ALX/FPR2 receptor), a G-protein-coupled receptor whose biological function is tremendously complex, primarily due to its capacity to mediate variable cellular responses. Moreover, lipoxins can also interact with alternative receptors like the cytoplasmic aryl hydrocarbon receptor, the cysteinyl-leukotrienes receptors or GPR32, triggering different intracellular signaling pathways. The available information about this complex response mediated by lipoxins is addressed in this review, going over the different mechanisms used by these molecules to stop the inflammatory reaction and avoid the development of dysregulated and chronic pathologies.
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Lipoxinas , Humanos , Lipoxinas/metabolismo , Receptores de Formil Péptido/metabolismo , Transducción de Señal , Inflamación , Receptores de Lipoxina/metabolismoRESUMEN
We previously reported that the loss of activity of an essential DNA repair enzyme, polynucleotide kinase 3'-phosphatase (PNKP), resulted in accumulation of double strand breaks (DSB) in patient's brain genome in Huntington's disease (HD) and Spinocerebellar ataxia type 3 (SCA3). Here we document that PNKP interacts with the nuclear isoform of phosphofructokinase fructose-2,6-bisphosphatase 3 (PFKFB3), which converts fructose-6-phosphate (F6P) into fructose-2,6-bisphosphate (F2,6BP), a potent allosteric modulator of glycolysis. Depletion of PFKFB3 markedly abrogates PNKP activity, thereby affecting PNKP mediated transcription-coupled non-homologous end joining (TC-NHEJ). Both PFKFB3 and F2,6BP levels are significantly lower in the nuclear extracts of HD and SCA3 patients' brains. Exogenous F2,6BP restored PNKP activity in the brain nuclear extracts of those samples. Moreover, delivery of F2,6BP into HD mouse striata-derived neuronal cells restored PNKP activity, transcribed genome integrity and cellular viability. We thus postulate that F2,6BP serves in vivo as a cofactor for proper functionality of PNKP and thereby of brain health. Our results thus provide a compelling rationale for exploring therapeutic use of F2,6BP and related compounds for treating polyQ diseases.
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Autophagy inducers can prevent cardiovascular aging and age-associated diseases including atherosclerosis. Therefore, we hypothesized that autophagy-inducing compounds that act on atherosclerosis-relevant cells might have a protective role in the development of atherosclerosis. Here we identified 3,4-dimethoxychalcone (3,4-DC) as an inducer of autophagy in several cell lines from endothelial, myocardial and myeloid/macrophagic origin, as demonstrated by the aggregation of the autophagosome marker GFP-LC3 in the cytoplasm of cells, as well as the downregulation of its nuclear pool indicative of autophagic flux. In this respect, 3,4-DC showed a broader autophagy-inducing activity than another chalcone (4,4- dimethoxychalcone), spermidine and triethylene tetramine. Thus, we characterized the potential antiatherogenic activity of 3,4-DC in two different mouse models, namely, (i) neointima formation with smooth muscle expansion of vein segments grafted to the carotid artery and (ii) genetically predisposed ApoE-/- mice fed an atherogenic diet. In the vein graft model, local application of 3,4-DC was able to maintain the lumen of vessels and to reduce neointima lesions. In the diet-induced model, intraperitoneal injections of 3,4-DC significantly reduced the number of atherosclerotic lesions in the aorta. In conclusion, 3,4-DC stands out as an autophagy inducer with potent antiatherogenic activity.
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Aterosclerosis , Neointima , Ratones , Animales , Neointima/tratamiento farmacológico , Neointima/patología , Hiperplasia/patología , Aterosclerosis/patología , Aorta/patología , Modelos Animales de Enfermedad , Autofagia , Ratones Endogámicos C57BLRESUMEN
In recent years, the central role of cell bioenergetics in regulating immune cell function and fate has been recognized, giving rise to the interest in immunometabolism, an area of research focused on the interaction between metabolic regulation and immune function. Thus, early metabolic changes associated with the polarization of macrophages into pro-inflammatory or pro-resolving cells under different stimuli have been characterized. Tumor-associated macrophages are among the most abundant cells in the tumor microenvironment; however, it exists an unmet need to study the effect of chemotherapeutics on macrophage immunometabolism. Here, we use a systems biology approach that integrates transcriptomics and metabolomics to unveil the immunometabolic effects of trabectedin (TRB) and lurbinectedin (LUR), two DNA-binding agents with proven antitumor activity. Our results show that TRB and LUR activate human macrophages toward a pro-inflammatory phenotype by inducing a specific metabolic rewiring program that includes ROS production, changes in the mitochondrial inner membrane potential, increased pentose phosphate pathway, lactate release, tricarboxylic acids (TCA) cycle, serine and methylglyoxal pathways in human macrophages. Glutamine, aspartate, histidine, and proline intracellular levels are also decreased, whereas oxygen consumption is reduced. The observed immunometabolic changes explain additional antitumor activities of these compounds and open new avenues to design therapeutic interventions that specifically target the immunometabolic landscape in the treatment of cancer.
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Neoplasias , Humanos , Trabectedina/farmacología , Macrófagos , Ácido Láctico , Microambiente TumoralRESUMEN
Macrophages are essential components of the innate immune system that play both homeostatic roles in healthy organs, and host defence functions against pathogens after tissue injury. To accomplish their physiological role, macrophages display different profiles of gene expression, immune function, and metabolic phenotypes that allow these cells to participate in different steps of the inflammatory reaction, from the initiation to the resolution phase. In addition, significant differences exist in the phenotype of macrophages depending on the tissue in which they are present and on the mammalian species. From a metabolic point of view, macrophages are essentially glycolytic cells; however, their metabolic fluxes are dependent on the functional polarisation of these cells. This metabolic and cellular plasticity offers the possibility to interfere with the activity of macrophages to avoid harmful effects due to persistent activation or the release of molecules that delay tissue recovery after injury.
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Inflamación , Macrófagos , Humanos , Homeostasis , Inflamación/metabolismo , Activación de Macrófagos , Macrófagos/metabolismo , FenotipoRESUMEN
Background & Aims: Lipotoxicity triggers non-alcoholic fatty liver disease (NAFLD) progression owing to the accumulation of toxic lipids in hepatocytes including saturated fatty acids (SFAs), which activate pro-inflammatory pathways. We investigated the impact of hepatocyte- or circulating-derived small extracellular vesicles (sEV) secreted under NAFLD conditions on liver inflammation and hepatocyte insulin signalling. Methods: sEV released by primary mouse hepatocytes, characterised and analysed by lipidomics, were added to mouse macrophages/Kupffer cells (KC) to monitor internalisation and inflammatory responses. Insulin signalling was analysed in hepatocytes exposed to conditioned media from sEV-loaded macrophages/KC. Mice were i.v. injected sEV to study liver inflammation and insulin signalling. Circulating sEV from mice and humans with NAFLD were used to evaluate macrophage-hepatocyte crosstalk. Results: Numbers of sEV released by hepatocytes increased under NAFLD conditions. Lipotoxic sEV were internalised by macrophages through the endosomal pathway and induced pro-inflammatory responses that were ameliorated by pharmacological inhibition or deletion of Toll-like receptor-4 (TLR4). Hepatocyte insulin signalling was impaired upon treatment with conditioned media from macrophages/KC loaded with lipotoxic sEV. Both hepatocyte-released lipotoxic sEV and the recipient macrophages/KC were enriched in palmitic (C16:0) and stearic (C18:0) SFAs, well-known TLR4 activators. Upon injection, lipotoxic sEV rapidly reached KC, triggering a pro-inflammatory response in the liver monitored by Jun N-terminal kinase (JNK) phosphorylation, NF-κB nuclear translocation, pro-inflammatory cytokine expression, and infiltration of immune cells into the liver parenchyma. sEV-mediated liver inflammation was attenuated by pharmacological inhibition or deletion of TLR4 in myeloid cells. Macrophage inflammation and subsequent hepatocyte insulin resistance were also induced by circulating sEV from mice and humans with NAFLD. Conclusions: We identified hepatocyte-derived sEV as SFA transporters targeting macrophages/KC and activating a TLR4-mediated pro-inflammatory response enough to induce hepatocyte insulin resistance. Impact and Implications: Small extracellular vesicles (sEV) released by the hepatocytes under non-alcoholic fatty liver disease (NAFLD) conditions cause liver inflammation and insulin resistance in hepatocytes via paracrine hepatocyte-macrophage-hepatocyte crosstalk. We identified sEV as transporters of saturated fatty acids (SFAs) and potent lipotoxic inducers of liver inflammation. TLR4 deficiency or its pharmacological inhibition ameliorated liver inflammation induced by hepatocyte-derived lipotoxic sEV. Evidence of this macrophage-hepatocyte interactome was also found in patients with NAFLD, pointing to the relevance of sEV in SFA-mediated lipotoxicity in NAFLD.
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Experimental evidence indicates that the control of the inflammatory response after myocardial infarction is a key strategy to reduce cardiac injury. Cellular damage after blood flow restoration in the heart promotes sterile inflammation through the release of molecules that activate pattern recognition receptors, among which TLR4 is the most prominent. Transient regulation of TLR4 activity has been considered one of the potential therapeutic interventions with greater projection towards the clinic. In this regard, the characterization of an aptamer (4FT) that acts as a selective antagonist for human TLR4 has been investigated in isolated macrophages from different species and in a rat model of cardiac ischemia/reperfusion (I/R). The binding kinetics and biological responses of murine and human macrophages treated with 4FT show great affinity and significant inhibition of TLR4 signaling including the NF-κB pathway and the LPS-dependent increase in the plasma membrane currents (Kv currents). In the rat model of I/R, administration of 4FT following reoxygenation shows amelioration of cardiac injury function and markers, a process that is significantly enhanced when the second dose of 4FT is administered 24 h after reperfusion of the heart. Parameters such as cardiac injury biomarkers, infiltration of circulating inflammatory cells, and the expression of genes associated with the inflammatory onset are significantly reduced. In addition, the expression of anti-inflammatory genes, such as IL-10, and pro-resolution molecules, such as resolvin D1 are enhanced after 4FT administration. These results indicate that targeting TLR4 with 4FT offers new therapeutic opportunities to prevent cardiac dysfunction after infarction.
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Infarto del Miocardio , Receptor Toll-Like 4 , Ratas , Ratones , Humanos , Animales , Receptor Toll-Like 4/metabolismo , Infarto del Miocardio/tratamiento farmacológico , Transducción de Señal , FN-kappa B/metabolismo , Corazón , OligonucleótidosRESUMEN
Immune cells have an important role in the tumor-microenvironment. Macrophages may tune the immune response toward inflammatory or tolerance pathways. Tumor-associated macrophages (TAM) have a string of immunosuppressive functions and they are considered a therapeutic target in cancer. This study aimed to analyze the effects of trabectedin, an antitumor agent, on the tumor-microenvironment through the characterization of the electrophysiological and molecular phenotype of macrophages. Experiments were performed using the whole-cell configuration of the patch-clamp technique in resident peritoneal mouse macrophages. Trabectedin does not directly interact with KV1.5 and KV1.3 channels, but their treatment (16 h) with sub-cytotoxic concentrations of trabectedin increased their KV current due to an upregulation of KV1.3 channels. In vitro generated TAM (TAMiv) exhibited an M2-like phenotype. TAMiv generated a small KV current and express high levels of M2 markers. K+ current from TAMs isolated from tumors generated in mice is a mixture of KV and KCa, and in TAM isolated from tumors generated in trabectedin-treated mice, the current is mostly driven by KCa. We conclude that the antitumor capacity of trabectedin is not only due to its effects on tumor cells, but also to the modulation of the tumor microenvironment, due, at least in part, to the modulation of the expression of different macrophage ion channels.
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Macrófagos , Microambiente Tumoral , Ratones , Animales , Trabectedina/farmacología , Macrófagos/metabolismo , Activación de Macrófagos , Fenómenos ElectrofisiológicosRESUMEN
The biochemical mechanisms of cell injury and myocardial cell death after myocardial infarction remain unresolved. Cyclooxygenase 2 (COX-2), a key enzyme in prostanoid synthesis, is expressed in human ischemic myocardium and dilated cardiomyopathy, but it is absent in healthy hearts. To assess the role of COX-2 in cardiovascular physiopathology, we developed transgenic mice that constitutively express functional human COX-2 in cardiomyocytes under the control of the α-myosin heavy chain promoter. These animals had no apparent phenotype but were protected against ischemia-reperfusion injury in isolated hearts, with enhanced functional recovery and diminished cellular necrosis. To further explore the phenotype of this animal model, we carried out a differential proteome analysis of wild-type vs. transgenic cardiomyocytes. The results revealed a tissue-specific proteomic profile dominated by mitochondrial proteins. In particular, an increased expression of respiratory chain complex IV proteins was observed. This correlated with increased catalytic activity, enhanced respiratory capacity, and increased ATP levels in the heart of COX-2 transgenic mice. These data suggest a new link between COX-2 and mitochondria, which might contribute to the protective cardiac effects of COX-2 against ischemia-reperfusion injury.
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Daño por Reperfusión Miocárdica , Miocitos Cardíacos , Ratones , Animales , Humanos , Miocitos Cardíacos/metabolismo , Ciclooxigenasa 2/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Proteómica , Transporte de Electrón , Miocardio/metabolismo , Ratones TransgénicosRESUMEN
Metabolic reprogramming is required to fight infections and thyroid hormones are key regulators of metabolism. We have analyzed in hospitalized COVID-19 patients: 40 euthyroid and 39 levothyroxine (LT4)-treated patients in the ward and 29 euthyroid and 9 LT4-treated patients in the intensive care unit (ICU), the baseline characteristics, laboratory data, thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), the FT3/FT4 ratio, 11 antiviral cytokines and 74 metabolomic parameters. No evidence for significant differences between euthyroid and LT4-treated patients were found in the biochemical, metabolomic and cytokines parameters analyzed. Only TSH (p=0.009) and ferritin (p=0.031) showed significant differences between euthyroid and LT4-treated patients in the ward, and TSH (p=0.044) and FT4 (p=0.012) in the ICU. Accordingly, severity and mortality were similar in euthyroid and LT4-treated patients. On the other hand, FT3 was negatively related to age (p=0.012), independently of sex and body mass index in hospitalized COVID-19 patients. Patients with low FT3 and older age showed a worse prognosis and higher levels of the COVID-19 severity markers IL-6 and IL-10 than patients with high FT3. IL-6 negatively correlated with FT3 (p=0.023) independently of age, body mass index and sex, whereas IL-10 positively associated with age (p=0.035) independently of FT3, body mass index and sex. A metabolomic cluster of 6 parameters defined low FT3 ward patients. Two parameters, esterified cholesterol (p=4.1x10-4) and small HDL particles (p=6.0x10-5) correlated with FT3 independently of age, body mass index and sex, whereas 3-hydroxybutyrate (p=0.010), acetone (p=0.076), creatinine (p=0.017) and high-density-lipoprotein (HDL) diameter (p=8.3x10-3) were associated to FT3 and also to age, with p-values of 0.030, 0.026, 0.017 and 8.3x10-3, respectively. In conclusion, no significant differences in FT3, cytokines, and metabolomic profile, or in severity and outcome of COVID-19, were found during hospitalization between euthyroid patients and hypothyroid patients treated with LT4. In addition, FT3 and age negatively correlate in COVID-19 patients and parameters that predict poor prognosis were associated with low FT3, and/or with age. A metabolomic cluster indicative of a high ketogenic profile defines non-critical hospitalized patients with low FT3 levels.