94 research outputs found

    Cerium oxide nanoparticles display antilipogenic effect in rats with non-alcoholic fatty liver disease

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    Cerium oxide nanoparticles; Non-alcoholic fatty liver disease; Antioxidant agentNanopartículas de óxido de cerio; Enfermedad del hígado graso no alcohólico; Agente antioxidanteNanopartícules d’òxid de ceri; Malalties hepàtiques no alcohòliques; Agent antioxidantNon-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide, ranging from steatosis to non-alcoholic steatohepatitis (NASH). Recently, cerium oxide nanoparticles (CeO2NPs) have emerged as a new antioxidant agent with hepatoprotective properties in experimental liver disease. The aim of the current investigation was to elucidate whether CeO2NPs display beneficial effects in an experimental model of NAFLD.Therefore, fifteen Wistar rats were subjected to a methionine and choline deficient diet (MCDD) for 6 weeks and intravenously treated with CeO2NP or vehicle during the weeks three and four of the diet. The effect of CeO2NPs on serum biochemistry, hepatic steatosis, inflammation, fatty acid content and expression of reactive oxygen species (ROS) and lipid metabolism related genes was assessed. MCDD fed rats showed increased inflammation, enhanced hepatic lipid accumulation of both saturated and unsaturated fatty acids (FAs) and overexpression of genes related to fatty liver and ROS metabolism. Treatment with CeO2NPs was able to reduce the size and content of hepatocyte lipid droplets, the hepatic concentration of triglyceride- and cholesterol ester-derived FAs and the expression of several genes involved in cytokine, adipokine and chemokine signaling pathways. These findings suggest that CeO2NPs could be of beneficial value in NAFLD.This research was supported by grants to W. Jiménez from Ministerio de Economia y Competitividad [grants SAF2015-64126R, 12-35979, BES-2013-063685, SAFRTI2018-094734-B-C21], to M. Morales-Ruiz [grant SAF2016-75358-R] and to G. Casals [grant P74844I/15/00777]; Cofinanced by FEDER, European Union, a way of making Europe, Agència de Gestió d’Ajuts Universitaris i de Recerca [grant SGR 2014/219]. The Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) is funded by the Instituto de Salud Carlos III

    Intrinsic and extrinsic properties affecting innate immune responses to nanoparticles : The case of cerium oxide

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    We review the apparent discrepancies between studies that report anti-inflammatory effects of cerium oxide nanoparticles (CeO NPs) through their reactive oxygen specieschelating properties and immunological studies highlighting their toxicity. We observe that several underappreciated parameters, such as aggregation size and degree of impurity, are critical determinants that need to be carefully addressed to better understand the NP biological effects in order to unleash their potential clinical benefits. This is because NPs can evolve toward different states, depending on the environment where they have been dispersed and how they have been dispersed. As a consequence, final characteristics of NPs can be very different from what was initially designed and produced in the laboratory. Thus, aggregation, corrosion, and interaction with extracellular matrix proteins critically modify NP features and fate. These modifications depend to a large extent on the characteristics of the biological media in which the NPs are dispersed. As a consequence, when reviewing the scientific literature, it seems that the aggregation state of NPs, which depends on the characteristics of the dispersing media, may be more significant than the composition or original size of the NPs. In this work, we focus on CeO NPs, which are reported sometimes to be protective and anti-inflammatory, and sometimes toxic and pro-inflammatory

    Cerium oxide nanoparticles improve liver regeneration after acetaminophen-induced liver injury and partial hepatectomy in rats

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    Background and aims: Cerium oxide nanoparticles are effective scavengers of reactive oxygen species and have been proposed as a treatment for oxidative stress-related diseases. Consequently, we aimed to investigate the effect of these nanoparticles on hepatic regeneration after liver injury by partial hepatectomy and acetaminophen overdose. Methods: All the in vitro experiments were performed in HepG2 cells. For the acetaminophen and partial hepatectomy experimental models, male Wistar rats were divided into three groups: (1) nanoparticles group, which received 0.1 mg/kg cerium nanoparticles i.v. twice a week for 2 weeks before 1 g/kg acetaminophen treatment, (2) N-acetyl-cysteine group, which received 300 mg/kg of N-acetyl-cysteine i.p. 1 h after APAP treatment and (3) partial hepatectomy group, which received the same nanoparticles treatment before partial hepatectomy. Each group was matched with vehicle-controlled rats. Results: In the partial hepatectomy model, rats treated with cerium oxide nanoparticles showed a significant increase in liver regeneration, compared with control rats. In the acetaminophen experimental model, nanoparticles and N-acetyl-cysteine treatments decreased early liver damage in hepatic tissue. However, only the effect of cerium oxide nanoparticles was associated with a significant increment in hepatocellular proliferation. This treatment also reduced stress markers and increased cell cycle progression in hepatocytes and the activation of the transcription factor NF-κB in vitro and in vivo. Conclusions: Our results demonstrate that the nanomaterial cerium oxide, besides their known antioxidant capacities, can enhance hepatocellular proliferation in experimental models of liver regeneration and drug-induced hepatotoxicity

    Beyond the Scavenging of Reactive Oxygen Species (ROS): Direct Effect of Cerium Oxide Nanoparticles in Reducing Fatty Acids Content in an In Vitro Model of Hepatocellular Steatosis

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    Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic accumulation of lipids. Antisteatotic effects of cerium oxide nanoparticles (CeO2NPs) have recently been shown in animal models of liver disease. However, it is unclear whether the activity of CeO2NPs is related solely to the decrease in oxidative stress or, in addition, they directly decrease liver fatty acid accumulation. To address this question, in this work, we used an in vitro model of hepatocellular steatosis, exposing HepG2 cells to oleic and palmitic acid. Cell uptake of CeO2NPs and their effect on oxidative stress and viability of hepatic cells cultured with H2O2 were also evaluated. Results show that CeO2NPs were uptaken by HepG2 cells and reduced oxidative stress and improved cell viability. Treatment with oleic and palmitic acid increased lipogenesis and the content of different fatty acids. CeO2NPs reduced palmitic and stearic acid and most fatty acids consisting of more than 18 carbon atoms. These effects were associated with significant changes in elongase and desaturase activity. In conclusion, CeO2NPs directly protected HepG2 cells from cell injury in oxidative stress conditions and reduced fatty acid content in steatotic conditions by inducing specific changes in fatty acid metabolism, thus showing potential in the treatment of NAFLD

    Recommendations for the measurement of sexual steroids in clinical practice. A position statement of SEQCML/SEEN/SEEP

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    Immunoassay; Sexual steroids; TestosteroneImmunoassaig; Esteroides sexuals; TestosteronaInmunoensayo; Esteroides sexuales; TestosteronaThe proper clinical approach to a wide range of disorders relies on the availability of accurate, reproducible laboratory results for sexual steroids measured using methods with a high specificity and sensitivity. The chemiluminescent immunoassays currently available have analytical limitations with significant clinical implications. This position statement reviews the current limitations of laboratory techniques for the measurement of estradiol and testosterone and their impact on diverse clinical scenarios. A set of recommendations are provided to incorporate steroid hormone analysis by mass spectrometry in national health systems. International societies have recommended this methodology for a decade

    Ketoconazole- and Metyrapone-Induced Reductions on Urinary Steroid Metabolites Alter the Urinary Free Cortisol Immunoassay Reliability in Cushing Syndrome

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    Introduction: Twenty-four-hour urinary free cortisol (24h-UFC) is the most used test for follow-up decision-making in patients with Cushing syndrome (CS) under medical treatment. However, 24h-UFC determinations by immunoassays (IA) are commonly overestimated because of steroid metabolites' cross-reaction. It is still uncertain how ketoconazole (KTZ)- and metyrapone (MTP)-induced changes on the urinary steroid metabolites can alter the 24h-UFC*IA determinations' reliability. Methods: 24h-UFC was analyzed by IA and gas chromatography-mass spectrometry (GC-MS) in 193 samples (81 before treatment, 73 during KTZ, and 39 during MTP) from 34 CS patients. In addition, urinary steroidome was analyzed by GC-MS on each patient before and during treatment. Results: Before treatment, 24h-UFC*IA determinations were overestimated by a factor of 1.75 (95% CI 1.60-1.94) compared to those by GC-MS. However, during KTZ treatment, 24h-UFC*IA results were similar (0.98:1) to those by GC-MS (95% CI, 0.83-1.20). In patients taking MTP, IA bias only decreased 0.55, resulting in persistence of an overestimation factor of 1.33:1 (95% CI, 1.09-1.76). High method agreement between GC-MS and IA before treatment (R2 = 0.954) declined in patients under KTZ (R2 = 0.632) but not in MTP (R2 = 0.917). Upper limit normal (ULN) reductions in patients taking KTZ were 27% larger when using 24h-UFC*IA compared to 24h-UFC*GC-MS, which resulted in higher false efficacy and misleading biochemical classification of 15% of patients. Urinary excretion changes of 22 urinary steroid metabolites explained 86% of the 24h-UFC*IA interference. Larger urinary excretion reductions of 6β-hydroxy-cortisol, 20α-dihydrocortisol, and 18-hydroxy-cortisol in patients with KTZ elucidated the higher 24h-UFC*IA bias decrement compared to MTP-treated patients. Conclusion: KTZ and MTP alter the urinary excretion of IA cross-reactive steroid metabolites, thus decreasing the cross-reactive interference of 24h-UFC*IA determinations present before treatment. Consequently, this interference reduction in 24h-UFC*IA leads to loss of method agreement with GC-MS and high risk of overestimating the biochemical impact of KTZ and MTP in controlling CS because of poor reliability of reference ranges and ULN

    Lack of a 5.9 kDa peptide C-terminal fragment of fibrinogen α chain precedes fibrosis progression in patients with liver disease

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    Early detection of fibrosis progression is of major relevance for the diagnosis and management of patients with liver disease. This study was designed to find non-invasive biomarkers for fibrosis in a clinical context where this process occurs rapidly, HCV-positive patients who underwent liver transplantation (LT). We analyzed 93 LT patients with HCV recurrence, 41 non-LT patients with liver disease showing a fibrosis stage F≥1 and 9 patients without HCV recurrence who received antiviral treatment before LT, as control group. Blood obtained from 16 healthy subjects was also analyzed. Serum samples were fractionated by ion exchange chromatography and their proteomic profile was analyzed by SELDI-TOF-MS. Characterization of the peptide of interest was performed by ion chromatography and electrophoresis, followed by tandem mass spectrometry identification. Marked differences were observed between the serum proteome profile of LT patients with early fibrosis recurrence and non-recurrent LT patients. A robust peak intensity located at 5905 m/z was the distinguishing feature of non-recurrent LT patients. However, the same peak was barely detected in recurrent LT patients. Similar results were found when comparing samples of healthy subjects with those of non-LT fibrotic patients, indicating that our findings were not related to either LT or HCV infection. Using tandem mass-spectrometry, we identified the protein peak as a C-terminal fragment of the fibrinogen α chain. Cell culture experiments demonstrated that TGF-β reduces α-fibrinogen mRNA expression and 5905 m/z peak intensity in HepG2 cells, suggesting that TGF-β activity regulates the circulating levels of this protein fragment. In conclusion, we identified a 5.9 kDa C-terminal fragment of the fibrinogen α chain as an early serum biomarker of fibrogenic processes in patients with liver disease

    Functionalized cerium oxide nanoparticles mitigate the oxidative stress and proinflammatory activity associated to the portal vein endothelium of cirrhotic rats

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    Altres ajuts: Fundació La Marató de TV3 (Marató 120930)Background and aims- The occurrence of endothelial alterations in the liver and in the splanchnic vasculature of cirrhotic patients and experimental models of liver diseases has been demonstrated. However, the pathological role of the portal vein endothelium in this clinical context is scarcely studied and, therefore, deserves attention. In this context, we aimed to investigate whether pathological endothelial activation occurs in the portal vein of cirrhotic rats. Methods- Cirrhosis was induced in wistar rats by CCl inhalation. We generated immortalized endothelial cells from the portal vein of control (CT-iPVEC) and cirrhotic rats (CH-iPVEC) by retroviral transduction of the SV40 T antigen. We assessed differential gene expression and intracellular reactive oxygen species (ROS) levels in iPVECs and in portal veins of control and cirrhotic rats. Finally, we assessed the therapeutic effectiveness of cerium oxide nanoparticles (CeONP) on reversing PVEC activation and macrophage polarization. Results- CH-iPVECs overexpressed collagen-I, endothelin-1, TIMP-1, TIMP-2, IL-6 and PlGF genes. These results were consistent with the differential expression showed by whole portal veins from cirrhotic rats. In addition, CH-iPVECs showed a significant increase in intracellular ROS and the capacity of potentiating M1 polarization in macrophages. The treatment of CH-iPVECs with CeONPs blocked intracellular ROS formation and IL-6 and TIMP-2 gene overexpression. In agreement with the in vitro results, the chronic treatment of cirrhotic rats with CeONPs also resulted in the blockade of both ROS formation and IL-6 gene overexpression in whole portal veins. Conclusions- Endothelial cells from portal vein of cirrhotic rats depicted an abnormal phenotype characterized by a differential gene expression and the induction of M1 polarization in macrophages. We identified the excess of intracellular reactive oxygen species (ROS) as a major contributor to this altered phenotype. In addition, we demonstrated the utility of the nanomaterial cerium oxide as an effective antioxidant capable of reverse some of these pathological features associated with the portal vein in the cirrhosis condition

    Cerium Oxide Nanoparticles Protect against Oxidant Injury and Interfere with Oxidative Mediated Kinase Signaling in Human-Derived Hepatocytes

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    Cerium oxide nanoparticles (CeO2NPs) possess powerful antioxidant properties, thus emerging as a potential therapeutic tool in non-alcoholic fatty liver disease (NAFLD) progression, which is characterized by a high presence of reactive oxygen species (ROS). The aim of this study was to elucidate whether CeO2NPs can prevent or attenuate oxidant injury in the hepatic human cell line HepG2 and to investigate the mechanisms involved in this phenomenon. The effect of CeO2NPs on cell viability and ROS scavenging was determined, the differential expression of pro-inflammatory and oxidative stress-related genes was analyzed, and a proteomic analysis was performed to assess the impact of CeO2NPs on cell phosphorylation in human hepatic cells under oxidative stress conditions. CeO2NPs did not modify HepG2 cell viability in basal conditions but reduced H2O2- and lipopolysaccharide (LPS)-induced cell death and prevented H2O2-induced overexpression of MPO, PTGS1 and iNOS. Phosphoproteomic analysis showed that CeO2NPs reverted the H2O2-mediated increase in the phosphorylation of peptides related to cellular proliferation, stress response, and gene transcription regulation, and interfered with H2O2 effects on mTOR, MAPK/ERK, CK2A1 and PKACA signaling pathways. In conclusion, CeO2NPs protect HepG2 cells from cell-induced oxidative damage, reducing ROS generation and inflammatory gene expression as well as regulation of kinase-driven cell survival pathways

    Mesoporous silica coated CeO2nanozymes with combined lipid-lowering and antioxidant activity induce long-term improvement of the metabolic profile in obese Zucker rats

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    Obesity is one of the most important public health problems that is associated with an array of metabolic disorders linked to cardiovascular disease, stroke, type 2 diabetes, and cancer. A sustained therapeutic approach to stop the escalating prevalence of obesity and its associated metabolic comorbidities remains elusive. Herein, we developed a novel nanocomposite based on mesoporous silica coated cerium oxide (CeO2) nanozymes that reduce the circulating levels of fatty acids and remarkably improve the metabolic phenotype in a model of obese Zucker rats five weeks after its administration. Lipidomic and gene expression analyses showed an amelioration of the hyperlipidemia and of the hepatic and adipose metabolic dysregulations, which was associated with a down-regulation of the hepatic PI3K/mTOR/AKT pathway and a reduction of the M1 proinflammatory cytokine TNF-a. In addition, the coating of the CeO2 maximized its cell antioxidant protective effects and minimized non-hepatic biodistribution. The one-pot synthesis method for the nanocomposite fabrication is implemented entirely in aqueous solution, room temperature and open atmosphere conditions, favoring scalability and offering a safe and translatable lipid-lowering and antioxidant nanomedicine to treat metabolic comorbidities associated with obesity. This approach may be further applied to address other metabolic disorders related to hyperlipidemia, low-grade inflammation and oxidative stress.This research was supported by the Instituto de Salud Carlos III (PI19/00774 to G. C. and G. F.-V.), Dirección General de Investigación Científica y Técnica (RTI2018-094734-B-C2 to W. J.), co-financed by FEDER, European Union, “A way of making Europe”, and the Secretaria d'Universitats i Recerca del Departament d'Empresa i Coneixement de la Generalitat de Catalunya (2018_PROD_00187 to W. J.), the National Natural Science Foundation of China (31950410536 to E. C. and 22005221 to M. Z.), the Wuyi University Funding (2018TP010 to E. C., and 2018TP011 and 2020FKZX05 to M. Z.), Guangdong Science and Technology Department (2019A050512006 to E. C.), and the Academy of Finland (309374 to J. M. R.)
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