Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38612527

RESUMO

RNA helicase DHX15 plays a significant role in vasculature development and lung metastasis in vertebrates. In addition, several studies have demonstrated the overexpression of DHX15 in the context of hepatocellular carcinoma. Therefore, we hypothesized that this helicase may play a significant role in liver regeneration, physiology, and pathology. Dhx15 gene deficiency was generated by CRISPR/Cas9 in zebrafish and by TALEN-RNA in mice. AUM Antisense-Oligonucleotides were used to silence Dhx15 in wild-type mice. The hepatocellular carcinoma tumor induction model was generated by subcutaneous injection of Hepa 1-6 cells. Homozygous Dhx15 gene deficiency was lethal in zebrafish and mouse embryos. Dhx15 gene deficiency impaired liver organogenesis in zebrafish embryos and liver regeneration after partial hepatectomy in mice. Also, heterozygous mice presented decreased number and size of liver metastasis after Hepa 1-6 cells injection compared to wild-type mice. Dhx15 gene silencing with AUM Antisense-Oligonucleotides in wild-type mice resulted in 80% reduced expression in the liver and a significant reduction in other major organs. In addition, Dhx15 gene silencing significantly hindered primary tumor growth in the hepatocellular carcinoma experimental model. Regarding the potential use of DHX15 as a diagnostic marker for liver disease, patients with hepatocellular carcinoma showed increased levels of DHX15 in blood samples compared with subjects without hepatic affectation. In conclusion, Dhx15 is a key regulator of liver physiology and organogenesis, is increased in the blood of cirrhotic and hepatocellular carcinoma patients, and plays a key role in controlling hepatocellular carcinoma tumor growth and expansion in experimental models.


Assuntos
Carcinoma Hepatocelular , RNA Helicases , Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/genética , Oligonucleotídeos , RNA Helicases/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
2.
Mol Pharm ; 20(2): 886-904, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36563052

RESUMO

The integration of progressive technologies such as nanomedicine with the use of natural products from traditional medicine (TM) provides a unique opportunity for the longed-for harmonization between traditional and modern medicine. Although several actions have been initiated decades ago, a disparity of reasons including some misunderstandings between each other limits the possibilities of a truly complementation. Herein, we analyze some common challenges between nanomedicine and traditional Chinese medicine (TCM). These challenges, if solved in a consensual way, can give a boost to such harmonization. Nanomedicine is a recently born technology, while TCM has been used by the Chinese people for thousands of years. However, for these disciplines, the regulation and standardization of many of the protocols, especially related to the toxicity and safety, regulatory aspects, and manufacturing procedures, are under discussion. Besides, both TCM and nanomedicine still need to achieve a wider social acceptance. Herein, we first briefly discuss the strengths and weaknesses of TCM. This analysis serves to focus afterward on the aspects where TCM and nanomedicine can mutually help to bridge the existing gaps between TCM and Western modern medicine. As discussed, many of these challenges can be applied to TM in general. Finally, recent successful cases in scientific literature that merge TCM and nanomedicine are reviewed as examples of the benefits of this harmonization.


Assuntos
Produtos Biológicos , Medicamentos de Ervas Chinesas , Humanos , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/uso terapêutico , Nanomedicina
3.
Liver Int ; 42(3): 651-662, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35050550

RESUMO

BACKGROUND AND AIMS: PTTG1 is almost undetectable in adult livers but is highly expressed in hepatocarcinoma. While little is known about its involvement in liver fibrosis, PTTG1 expression is associated with DLK1. We assessed the role of the PTTG1/DLK1 pathway in fibrosis progression and the potential therapeutic effect of PTTG1 silencing in fibrosis. METHODS: Pttg1 and Dlk1 were studied in liver and isolated cell populations of control and fibrotic rats and in human liver biopsies. The fibrotic molecular signature was analysed in Pttg1-/- and Pttg1+/+ fibrotic mice. Finally, Pttg1 silencing was evaluated in rats as a novel antifibrotic therapy. RESULTS: Pttg1 and Dlk1 mRNA selectively increased in fibrotic rats paralleling fibrosis progression. Serum DLK1 concentrations correlated with hepatic collagen content and systemic and portal haemodynamics. Human cirrhotic livers showed greater PTTG1 and DLK1 transcript abundance than non-cirrhotic, and reduced collagen was observed in Pttg1 Pttg1-/- mice. The liver fibrotic molecular signature revealed lower expression of genes related to extracellular matrix remodelling including Mmp8 and 9 and Timp4 and greater eotaxin and Mmp13 than fibrotic Pttg1+/+ mice. Finally, interfering Pttg1 resulted in reduced liver fibrotic area, lower α-Sma and decreased portal pressure than fibrotic animals. Furthermore, Pttg1 silencing decreased the transcription of Dlk1, collagens I and III, Pdgfrß, Tgfrß, Timp1, Timp2 and Mmp2. CONCLUSIONS: Pttg1/Dlk1 are selectively overexpressed in the cirrhotic liver and participate in ECM turnover regulation. Pttg1 disruption decreases Dlk1 transcription and attenuates collagen deposition. PTTG1/DLK1 signalling is a novel pathway for targeting the progression of liver fibrosis.


Assuntos
Proteínas de Ligação ao Cálcio , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Membrana , Neoplasias Hipofisárias , Securina , Animais , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Fibrose , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fígado/patologia , Cirrose Hepática/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Oncogenes , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Ratos , Securina/genética , Securina/metabolismo
4.
Molecules ; 27(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35335253

RESUMO

Circulating levels of 2-hydroxybutyrate (2HB) are highly related to glycemic status in different metabolomic studies. According to recent evidence, 2HB is an early biomarker of the future development of dysglycemia and type 2 diabetes mellitus and may be causally related to the progression of normal subjects to impaired fasting glucose or insulin resistance. In the present study, we developed and validated a simple, specific and sensitive gas chromatography-mass spectrometry (GC-MS) method specifically intended to quantify serum levels of 2HB. Liquid-liquid extraction with ethyl acetate was followed by 2 min of microwave-assisted derivatization. The method presented acceptable accuracy, precision and recovery, and the limit of quantification was 5 µM. Levels of 2HB were found to be stable in serum after three freeze-thaw cycles, and at ambient temperature and at a temperature of 4 °C for up to 24 h. Extracts derivatized under microwave irradiation were stable for up to 96 h. No differences were found in 2HB concentrations measured in serum or plasma EDTA samples. In summary, the method is useful for a rapid, precise and accurate quantification of 2HB in serum samples assessed for the evaluation of dysglycemia and diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2 , Micro-Ondas , Biomarcadores , Diabetes Mellitus Tipo 2/diagnóstico , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Hidroxibutiratos
5.
Hepatology ; 72(4): 1267-1282, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31961955

RESUMO

BACKGROUND AND AIMS: Despite the availability of new-generation drugs, hepatocellular carcinoma (HCC) is still the third most frequent cause of cancer-related deaths worldwide. Cerium oxide nanoparticles (CeO2 NPs) have emerged as an antioxidant agent in experimental liver disease because of their antioxidant, anti-inflammatory, and antisteatotic properties. In the present study, we aimed to elucidate the potential of CeO2 NPs as therapeutic agents in HCC. APPROACH AND RESULTS: HCC was induced in 110 Wistar rats by intraperitoneal administration of diethylnitrosamine for 16 weeks. Animals were treated with vehicle or CeO2 NPs at weeks 16 and 17. At the eighteenth week, nanoceria biodistribution was assessed by mass spectrometry (MS). The effect of CeO2 NPs on tumor progression and animal survival was investigated. Hepatic tissue MS-based phosphoproteomics as well as analysis of principal lipid components were performed. The intracellular uptake of CeO2 NPs by human ex vivo perfused livers and human hepatocytes was analyzed. Nanoceria was mainly accumulated in the liver, where it reduced macrophage infiltration and inflammatory gene expression. Nanoceria treatment increased liver apoptotic activity, while proliferation was attenuated. Phosphoproteomic analysis revealed that CeO2 NPs affected the phosphorylation of proteins mainly related to cell adhesion and RNA splicing. CeO2 NPs decreased phosphatidylcholine-derived arachidonic acid and reverted the HCC-induced increase of linoleic acid in several lipid components. Furthermore, CeO2 NPs reduced serum alpha-protein levels and improved the survival of HCC rats. Nanoceria uptake by ex vivo perfused human livers and in vitro human hepatocytes was also demonstrated. CONCLUSIONS: These data indicate that CeO2 NPs partially revert the cellular mechanisms involved in tumor progression and significantly increase survival in HCC rats, suggesting that they could be effective in patients with HCC.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Cério/uso terapêutico , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Nanopartículas/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Cério/farmacocinética , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/mortalidade , Neoplasias Hepáticas Experimentais/patologia , Masculino , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , alfa-Fetoproteínas/análise
6.
Int J Mol Sci ; 22(9)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946157

RESUMO

The metabolic ratios lactate/pyruvate and ß-hydroxybutyrate/acetoacetate are considered valuable tools to evaluate the in vivo redox cellular state by estimating the free NAD+/NADH in cytoplasm and mitochondria, respectively. The aim of the current study was to validate a gas-chromatography mass spectrometry method for simultaneous determination of the four metabolites in plasma and liver tissue. The procedure included an o-phenylenediamine microwave-assisted derivatization, followed by liquid-liquid extraction with ethyl acetate and silylation with bis(trimethylsilyl)trifluoroacetamide:trimethylchlorosilane 99:1. The calibration curves presented acceptable linearity, with a limit of quantification of 0.001 mM for pyruvate, ß-hydroxybutyrate and acetoacetate and of 0.01 mM for lactate. The intra-day and inter-day accuracy and precision were within the European Medicines Agency's Guideline specifications. No significant differences were observed in the slope coefficient of three-point standard metabolite-spiked curves in plasma or liver and water, and acceptable recoveries were obtained in the metabolite-spiked samples. Applicability of the method was tested in precision-cut liver rat slices and also in HepG2 cells incubated under different experimental conditions challenging the redox state. In conclusion, the validated method presented good sensitivity, specificity and reproducibility in the quantification of lactate/pyruvate and ß-hydroxybutyrate/acetate metabolites and may be useful in the evaluation of in vivo redox states.


Assuntos
Ácido 3-Hidroxibutírico/metabolismo , Acetoacetatos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Lactatos/metabolismo , Piruvatos/metabolismo , Ácido 3-Hidroxibutírico/análise , Ácido 3-Hidroxibutírico/sangue , Acetoacetatos/análise , Acetoacetatos/sangue , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Células Hep G2 , Humanos , Lactatos/análise , Lactatos/sangue , Limite de Detecção , Fígado/química , Fígado/metabolismo , Oxirredução , Piruvatos/análise , Piruvatos/sangue , Ratos Wistar
7.
Small ; 16(20): e1907322, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32329572

RESUMO

Antioxidant nanoparticles have recently gained tremendous attention for their enormous potential in biomedicine. However, discrepant reports of either medical benefits or toxicity, and lack of reproducibility of many studies, generate uncertainties delaying their effective implementation. Herein, the case of cerium oxide is considered, a well-known catalyst in the petrochemistry industry and one of the first antioxidant nanoparticles proposed for medicine. Like other nanoparticles, it is now described as a promising therapeutic alternative, now as threatening to health. Sources of these discrepancies and how this analysis helps to overcome contradictions found for other nanoparticles are summarized and discussed. For the context of this analysis, what has been reported in the liver is reviewed, where many diseases are related to oxidative stress. Since well-dispersed nanoparticles passively accumulate in liver, it represents a major testing field for the study of new nanomedicines and their clinical translation. Even more, many contradictory works have reported in liver either cerium-oxide-associated toxicity or protection against oxidative stress and inflammation. Based on this, finally, the intention is to propose solutions to design improved nanoparticles that will work more precisely in medicine and safely in society.


Assuntos
Cério , Nanopartículas , Cério/toxicidade , Nanopartículas/toxicidade , Estresse Oxidativo , Reprodutibilidade dos Testes , Distribuição Tecidual
8.
J Nanobiotechnology ; 17(1): 112, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31672158

RESUMO

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.


Assuntos
Acetaminofen , Antioxidantes/uso terapêutico , Cério/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Regeneração Hepática/efeitos dos fármacos , Nanopartículas/uso terapêutico , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Células Hep G2 , Hepatectomia , Humanos , Fígado/efeitos dos fármacos , Fígado/fisiopatologia , Masculino , Ratos Wistar
9.
Int J Mol Sci ; 20(23)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783479

RESUMO

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.


Assuntos
Cério/farmacologia , Hepatócitos/efeitos dos fármacos , Nanopartículas/administração & dosagem , Oxidantes/metabolismo , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antioxidantes/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Lipopolissacarídeos/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteômica/métodos , Espécies Reativas de Oxigênio/metabolismo , Transcrição Gênica/efeitos dos fármacos
10.
Hepatology ; 63(1): 207-16, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26403564

RESUMO

UNLABELLED: Patients and rats with cirrhosis and ascites have portal hypertension and circulatory dysfunction. Synthetic arginine vasopressin (AVP) receptor agonists able to induce systemic and mesenteric vasoconstriction have shown their usefulness in reducing portal pressure (PP) in this condition. We assessed the potential therapeutic value of a new V1 a -AVP receptor partial agonist with a preferential splanchnic vasoconstrictor effect (FE 204038) in rats with cirrhosis and ascites. The hemodynamic effects of cumulative intravenous doses of FE 204038, terlipressin, or vehicle were investigated. Mean arterial pressure and PP were continuously recorded and cardiac output and systemic vascular resistance (SVR) assessed at 30-minute intervals for 90 minutes. Urine volume, urine osmolality, and urinary excretion of sodium and creatinine were measured in basal conditions and following twice-daily subcutaneous doses of FE 204038 or vehicle. PP, mean arterial pressure, cardiac output, SVR, and ascites volume were also measured after 6 days. The expression of an array of vasoactive genes was assessed in the thoracic aorta and the mesenteric circulation of control rats and rats with cirrhosis and ascites. FE 204038 dose-dependently decreased PP, did not modify mean arterial pressure, and increased SVR. The effect of the V1a -AVP receptor partial agonist on PP was associated with an improvement in urine volume and urinary excretion of sodium during the first day of treatment. SVR was higher and cardiac output and ascites volume were lower in rats with cirrhosis and ascites treated with FE 204038. V1a -AVP receptor expression in rats with cirrhosis and ascites was markedly enhanced in the mesenteric circulation compared to the thoracic aorta. CONCLUSION: FE 204038 increases sodium excretion and reduces portal hypertension and ascites in experimental cirrhosis. V1a -AVP receptor partial agonism could be a useful pharmacological treatment in decompensated patients with cirrhosis.


Assuntos
Ascite/tratamento farmacológico , Ascite/metabolismo , Hipertensão Portal/tratamento farmacológico , Hipertensão Portal/metabolismo , Cirrose Hepática/metabolismo , Receptores de Vasopressinas/agonistas , Sódio/metabolismo , Animais , Ascite/etiologia , Hipertensão Portal/etiologia , Cirrose Hepática/complicações , Masculino , Ratos , Ratos Wistar
11.
J Hepatol ; 64(3): 691-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26519601

RESUMO

BACKGROUND & AIMS: Cerium oxide nanoparticles (CeO2NPs) have proven to behave as free radical scavengers and/or anti-inflammatory agents. The aim of the study was to determine whether CeO2NPs display hepatoprotective properties in experimental chronic liver disease. METHODS: Systemic and hepatic effects of nanoparticles were assessed in CCl4-treated rats receiving CeO2NPs or vehicle twice weekly for two weeks and CCl4 treatment was continued for 8 additional weeks. Thereafter, mean arterial pressure and portal pressure (PP) were assessed and serum samples obtained to measure standard hepatic and renal function tests. Organ and subcellular distribution of NPs were assessed using mass spectrometry (ICP-MS) and transmission electron microscopy. Liver samples were obtained to evaluate steatosis, α-SMA expression, macrophage infiltration, apoptosis and mRNA expression of oxidative stress, inflammatory or vasoactive related genes. RESULTS: Most CeO2NPs were located in the liver and it reduced hepatic steatosis, ameliorated systemic inflammatory biomarkers and improved PP without affecting mean arterial pressure. In addition, a marked reduction in mRNA expression of inflammatory cytokines (TNFα, IL1ß, COX-2, iNOS), ET-1 and messengers related to oxidative (Epx, Ncf1, Ncf2) or endoplasmic reticulum (Atf3, Hspa5) stress signaling pathways was observed in the liver of rats receiving CeO2NPs. This was associated with reduced macrophage infiltration and reduced abundance of caspase-3, α-SMA and inflammatory cytokines. CONCLUSIONS: CeO2NPs administration to CCl4-treated rats protects against chronic liver injury by reducing liver steatosis and portal hypertension and markedly attenuating the intensity of the inflammatory response, thereby suggesting that CeO2NPs may be of therapeutic value in chronic liver disease.


Assuntos
Anti-Inflamatórios/uso terapêutico , Cério/uso terapêutico , Fígado Gorduroso/tratamento farmacológico , Hipertensão Portal/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Nanopartículas/administração & dosagem , Actinas/análise , Animais , Apoptose , Caspase 3/metabolismo , Cério/administração & dosagem , Cério/farmacologia , Estresse do Retículo Endoplasmático , Fígado/patologia , Ratos , Espécies Reativas de Oxigênio
12.
Liver Int ; 35(4): 1383-92, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24612347

RESUMO

BACKGROUND & AIMS: Studies in experimental models of cirrhosis showed that anti-angiogenic treatments may be effective for the treatment of liver fibrosis. In this context, angiopoietins are potential therapeutic targets as they are involved in the maintenance and stabilization of newly formed blood vessels. In addition, angiopoietin-2 is expressed in fibrotic livers and its inhibition in tumours results in vessel stability. Therefore, our study was aimed to assess the therapeutic utility of inhibiting angiopoietin-2. METHODS: Circulating levels of angiopoietin-1 and angiopoietin-2 were quantified by ELISA in CCl4 -treated rats and in patients with cirrhosis. In vivo blockade of angiopoietin-2 in rats with liver fibrosis was performed with a chemically programmed antibody, CVX-060. RESULTS: High levels of angiopoietin-2 were found in the systemic and suprahepatic circulation of cirrhotic patients and the ratio angiopoietin-1/angiopoietin-2 inversely correlated with prognostic models for alcoholic liver disease. Chronic treatment of CCl4 -treated rats with CVX-060 was associated with a significant decrease in inflammatory infiltrate, normalization of the hepatic microvasculature and reduction in VCAM-1 vascular expression. The anti-angiopoietin-2 treatment was also associated with less liver fibrosis and with lower levels of circulating transaminases. CVX-060 treatment was not associated with either vascular pruning in healthy tissue or compensatory overexpression of VEGF. CONCLUSIONS: Inhibition of angiopoietin-2 is an effective and safe treatment for liver fibrosis in CCl4 -treated rats, acting mainly through the induction of vessel normalization and the attenuation of hepatic inflammatory infiltrate. Therefore, inhibition of angiopoietin-2 offers a therapeutic alternative for liver fibrosis.


Assuntos
Inibidores da Angiogênese/farmacologia , Angiopoietina-2/antagonistas & inibidores , Hepatite Alcoólica/sangue , Imunoconjugados/farmacologia , Cirrose Hepática Alcoólica/sangue , Cirrose Hepática Experimental/prevenção & controle , Fígado/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Adulto , Angiopoietina-2/sangue , Angiopoietina-2/metabolismo , Animais , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Fígado/irrigação sanguínea , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Pessoa de Meia-Idade , Ratos Wistar , Receptor TIE-2/antagonistas & inibidores , Receptor TIE-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima , Molécula 1 de Adesão de Célula Vascular/metabolismo
13.
Gut ; 62(1): 138-45, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22267600

RESUMO

BACKGROUND AND AIM: The lymphatic network plays a major role in maintaining tissue fluid homoeostasis. Therefore several pathological conditions associated with oedema formation result in deficient lymphatic function. However, the role of the lymphatic system in the pathogenesis of ascites and oedema formation in cirrhosis has not been fully clarified. The aim of this study was to investigate whether the inability of the lymphatic system to drain tissue exudate contributes to the oedema observed in cirrhosis. METHODS: Cirrhosis was induced in rats by CCl(4) inhalation. Lymphatic drainage was evaluated using fluorescent lymphangiography. Expression of endothelial nitric oxide synthase (eNOS) was measured in primary lymphatic endothelial cells (LyECs). Inhibition of eNOS activity in cirrhotic rats with ascites (CH) was carried out by L-N(G)-methyl-L-arginine (L-NMMA) treatment (0.5 mg/kg/day). RESULTS: The (CH) rats had impaired lymphatic drainage in the splanchnic and peripheral regions compared with the control (CT) rats. LyECs isolated from the CH rats showed a significant increase in eNOS and nitric oxide (NO) production. In addition, the lymphatic vessels of the CH rats showed a significant reduction in smooth muscle cell (SMC) coverage compared with the CT rats. CH rats treated with L-NMMA for 7 days showed a significant improvement in lymphatic drainage and a significant reduction in ascites volume, which were associated with increased plasma volume. This beneficial effect of L-NMMA inhibition was also associated with a significant increase in lymphatic SMC coverage. CONCLUSIONS: The upregulation of eNOS in the LyECs of CH rats causes long-term lymphatic remodelling, which is characterised by a loss of SMC lymphatic coverage. The amelioration of this lymphatic abnormality by chronic eNOS inhibition results in improved lymphatic drainage and reduced ascites.


Assuntos
Células Endoteliais/metabolismo , Cirrose Hepática/fisiopatologia , Sistema Linfático/fisiopatologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Animais , Ascite/etiologia , Biomarcadores/metabolismo , Tetracloreto de Carbono , Endotélio Linfático/metabolismo , Endotélio Linfático/patologia , Endotélio Linfático/fisiopatologia , Cirrose Hepática/induzido quimicamente , Sistema Linfático/metabolismo , Sistema Linfático/patologia , Linfografia , Masculino , Miócitos de Músculo Liso/patologia , Óxido Nítrico Sintase/antagonistas & inibidores , Distribuição Aleatória , Ratos , Ratos Wistar , ômega-N-Metilarginina/metabolismo
14.
Biomolecules ; 14(5)2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38785966

RESUMO

INTRODUCTION: Urine free cortisol measurements are routinely performed to evaluate hypercortisolism. Despite their analytical inaccuracy, immunoassay-based methods are frequently used. Advances in liquid chromatography-high-resolution mass spectrometry (LC-HRMS) facilitate the incorporation of powerful diagnostic tools into clinical laboratories. In addition to its high analytical specificity and simultaneous analysis of different metabolites, accurate mass measurement allows for untargeted compound identification, which may help to identify clinically relevant metabolites or drugs. METHODS: The present study aimed to validate a simple routine LC-HRMS method to quantify cortisol, cortisone, 6ß-hydroxycortisol, and 18-hydroxycortisol simultaneously in human urine. Additionally, the study also validated a GC-MS method for the same steroids, evaluated their cross-reactivity with commercial cortisol immunoassays, and quantified the 24 h urine excretion in patients under clinical suspicion or follow-up for hypercortisolism. RESULTS: The LC-HRMS method involved liquid-liquid extraction using dichloromethane, micro-LC for chromatographic separation and detection using the accurate masses of the steroids, and simultaneous high-resolution full scan acquisition. The method presented acceptable linearity, precision, and accuracy. Significant interference from 6ß-hydroxycortisol and cortisone was demonstrated in the cortisol immunoassays, which impacted their reliability in the follow-up of patients with hypercortisolism and significant changes in these cortisol metabolites (i.e., due to drug-induced changes in CYP3A4 activity). CONCLUSION: A rapid and accurate routine LC-HRMS method was validated, which is useful for the evaluation of hypercortisolism and other disorders of glucocorticoid and mineralocorticoid metabolism.


Assuntos
Cortisona , Cromatografia Gasosa-Espectrometria de Massas , Hidrocortisona , Humanos , Hidrocortisona/urina , Hidrocortisona/análogos & derivados , Cortisona/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Líquida/métodos , Glucocorticoides/urina , Síndrome de Cushing/urina , Síndrome de Cushing/diagnóstico , Masculino , Feminino
15.
Biomed Pharmacother ; 171: 116143, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219387

RESUMO

Nitric oxide (NO) is a small vasodilator playing a key role in the pathogenesis of portal hypertension. Here, we assessed the potential therapeutic effect of a NO donor targeted to the liver by poly(beta-amino ester) nanoparticles (pBAE NPs) in experimental cirrhosis. Retinol-functionalized NO donor pBAE NPs (Ret pBAE NPs) were synthetized with the aim of actively targeting the liver. Administration of Ret pBAE NPs resulted in uptake and transfection by the liver and spleen. NPs were not found in other organs or the systemic circulation. Treatment with NO donor Ret pBAE NPs (30 mg/ kg body weight) significantly decreased aspartate aminotransferase, lactate dehydrogenase and portal pressure (9.75 ± 0.64 mmHg) compared to control NPs (13.4 ± 0.53 mmHg) in cirrhotic rats. There were no effects on mean arterial pressure and cardiac output. Liver-targeted NO donor NPs reduced collagen fibers and steatosis, activation of hepatic stellate cells and mRNA expression of profibrogenic and proinflammatory genes. Finally, Ret pBAE NPs displayed efficient transfection in human liver slices. Overall, liver-specific NO donor NPs effectively target the liver and mitigated inflammation and portal hypertension in cirrhotic rats. The use of Ret pBAE may prove to be an effective therapeutic strategy to treat advanced liver disease.


Assuntos
Hipertensão Portal , Cirrose Hepática Experimental , Nanopartículas , Ratos , Humanos , Animais , Óxido Nítrico/metabolismo , Fígado , Hipertensão Portal/tratamento farmacológico , Cirrose Hepática Experimental/metabolismo , Doadores de Óxido Nítrico/farmacologia , Cirrose Hepática/tratamento farmacológico
16.
Cell Physiol Biochem ; 32(5): 1125-36, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24247107

RESUMO

BACKGROUND: The molecular mechanisms by which myocardial ischemia translates into ventricular remodeling remain unclear. METHODS: We investigated whether hypoxia and proinflammatory cytokines are specific inducers of remodeling signals in an in vitro model of cultured adult human ventricular myocytes (AC16 cells). RESULTS: Hypoxia modified the ratio of matrix remodeling factors by increasing the aminoterminal propeptide of type III procollagen (PIIINP) and reducing tissue inhibitor of matrix metalloproteinase type 1 (TIMP-1) secretion in AC16 cells. These effects, however, were not associated with either modifications in expression of matrix metalloproteinase type 2, collagen-I or metalloproteinase activity. Hypoxia does, actually increase the production of the cardiac antifibrogenic growth factors, Apelin and VEGF, through an Hypoxia Inducible Factor type 1-dependent mechanism. Concerning proinflammatory signaling pathways, IL1ß emerged as a powerful inducer of matrix turnover, since it significantly enhanced PIIINP, TIMP-1 and hyaluronic acid production and increased metalloproteinase activity. In contrast, TNFα did not modify matrix turnover but markedly induced the production of Apelin and VEGF. CONCLUSION: Hypoxia and increased TNFα activity likely exert cardioprotective actions by activating the cardiac antifibrogenic factors Apelin and VEGF. In contrast, IL1ß is a strong promoter of interstitial collagen remodeling that may contribute to ventricular dilation and heart failure in the ischemic myocardium.


Assuntos
Matriz Extracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Miócitos Cardíacos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Remodelação Ventricular/fisiologia , Apelina , Hipóxia Celular/fisiologia , Células Cultivadas , Colágeno Tipo III/genética , Colágeno Tipo III/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Interleucina-1beta/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Miócitos Cardíacos/patologia , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética
17.
Biomed Pharmacother ; 165: 115116, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37418980

RESUMO

The vasopressin system has emerged as a therapeutic focus for lowering portal hypertension and reducing splanchnic vasodilation in patients with refractory ascites. Clinically available vasopressin agonists are limited by preferential selectivity for V1 receptors that also have steep concentration-response curves with potential risks of excess vasoconstriction and/or complete antidiuretic effects. OCE-205 is a novel, selective, partial V1a receptor agonist with mixed agonist/antagonist activity and no V2 receptor activation at therapeutic doses. We carried out two studies assessing the in vivo effects of OCE-205 in different rat models of cirrhosis and ascites. In a carbon tetrachloride rat cirrhosis model, OCE-205 administration produced a marked reduction in portal hypertension and hyperaldosteronism, along with robust diuretic and natriuretic effects. These effects were accompanied by marked decreases in ascites volume, with three of five animals experiencing total mobilization of ascites. There was no evidence of fluid overload or sodium or water retention, confirming OCE-205's lack of V2 receptor activity. In a second, corroborative study using a bile duct ligation rat model of ascites, OCE-205 produced significant decreases in ascites volume and body weight and a significant increase in urine volume versus vehicle. Urine sodium excretion increased significantly after the first administration of OCE-205 relative to vehicle; however, repeat administration over 5 days did not lead to hyponatremia. Thus, in separate in vivo models, the mixed agonist/antagonist OCE-205 demonstrated relevant and expected endpoint findings consistent with its known mechanism of action and in vitro pharmacology without apparent unwanted effects or nonspecific toxicities.


Assuntos
Hiperaldosteronismo , Hipertensão Portal , Ratos , Animais , Diuréticos/uso terapêutico , Natriuréticos , Ascite/tratamento farmacológico , Ascite/metabolismo , Vasopressinas/metabolismo , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Sódio/metabolismo , Receptores de Vasopressinas , Hipertensão Portal/tratamento farmacológico , Hipertensão Portal/metabolismo , Hiperaldosteronismo/complicações
18.
Nanoscale ; 15(35): 14365-14379, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37609757

RESUMO

Cerium oxide nanozymes (CeO2NZs) are attracting vast attention due to their antioxidant and catalytic properties and mimic the activities of multiple endogenous enzymes. However, as is the case for nanomedicines in general, the success in showing their unique medical applications has not been matched by an understanding of their pharmacokinetics, which is delaying their implementation in clinical settings. Furthermore, the data of their modifications in body fluids and the impact on their activity are scarce. Herein, two types of widely used CeO2NZs, electrostatically stabilized and coated with a mesoporous silica shell, were exposed to simulated saliva and lung, gastric and intestinal fluids, and cell culture media. Their physicochemical modifications and bioactivity were tracked over time up to 15 days combining the data of different characterization techniques and biological assays. The results show that the biocompatibility and antioxidant activity are retained in all cases despite the different evolution behaviors in different fluids, including agglomeration. This work provides an experimental basis from a pharmacokinetic perspective that supports the therapeutic effectiveness of CeO2NZs observed in vivo for the treatment of many conditions related to chronic inflammation and cancer, and suggests that they can be safely administered through different portals of entry including intravenous injection, oral ingestion or inhalation.


Assuntos
Líquidos Corporais , Saliva , Antioxidantes/farmacologia , Bioensaio , Catálise
19.
Antioxidants (Basel) ; 12(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36979013

RESUMO

Nanoparticle (NP) pharmacokinetics significantly differ from traditional small molecule principles. From this emerges the need to create new tools and concepts to harness their full potential and avoid unnecessary risks. Nanoparticle pharmacokinetics strongly depend on size, shape, surface functionalisation, and aggregation state, influencing their biodistribution, accumulation, transformations, and excretion profile, and hence their efficacy and safety. Today, while NP biodistribution and nanoceria biodistribution have been studied often at short times, their long-term accumulation and excretion have rarely been studied. In this work, 3 nm nanoceria at 5.7 mg/kg of body weight was intravenously administrated in a single dose to healthy mice. Biodistribution was measured in the liver, spleen, kidney, lung, brain, lymph nodes, ovary, bone marrow, urine, and faeces at different time points (1, 9, 30, and 100 days). Biodistribution and urinary and faecal excretion were also studied in rats placed in metabolic cages at shorter times. The similarity of results of different NPs in different models is shown as the heterogeneous nanoceria distribution in organs. After the expectable accumulation in the liver and spleen, the concentration of cerium decays exponentially, accounting for about a 50% excretion of cerium from the body in 100 days. Cerium ions, coming from NP dissolution, are most likely excreted via the urinary tract, and ceria nanoparticles accumulated in the liver are most likely excreted via the hepatobiliary route. In addition, nanoceria looks safe and does not damage the target organs. No weight loss or apathy was observed during the course of the experiments.

20.
J Hepatol ; 57(2): 281-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22521355

RESUMO

BACKGROUND & AIMS: Our aim was to evaluate a serologic marker (ELF) and two ultrasound-based methods (FibroScan and ARFI), as well as their combinations, in the assessment of liver fibrosis. METHODS: One-hundred and forty-six patients (87 liver transplant recipients, 59 non-transplant patients) who underwent liver biopsy were prospectively included. We evaluated the diagnostic accuracy of FibroScan, ARFI, ELF and the combination of ELF with either ARFI or FibroScan. After analyzing in separate transplant and non-transplant patients, the whole cohort was divided into a training set and a validation set. RESULTS: ARFI imaging was successfully performed across the whole cohort, while FibroScan failed in 16 (11%) patients. The three methods showed similar AUROCs and best cut-off values in transplant and non-transplant patients. In the training set, differences between the AUROCs of ARFI, FibroScan and ELF to diagnose F⩾2 (0.879, 0.861, and 0.764, respectively) and cirrhosis (0.936, 0.918, and 0.841) were not statistically significant, although both ultrasound-based methods showed higher accuracy than ELF. The combination of ELF with ARFI or FibroScan increased the negative and positive predictive values of single tests for the diagnosis of F ≥ 2 and cirrhosis. Similar results were obtained when the methods were tested in the validation set. CONCLUSIONS: ARFI is as effective as either FibroScan or ELF in the non-invasive assessment of liver fibrosis, and its inclusion in an ultrasound device could facilitate its incorporation into routine clinical practice. The combination of ARFI or FibroScan with ELF may help better identify patients with or without significant fibrosis or cirrhosis.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Cirrose Hepática/diagnóstico , Adulto , Idoso , Biópsia , Feminino , Humanos , Fígado/patologia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA