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1.
Cell Death Dis ; 15(4): 249, 2024 Apr 06.
Article in English | MEDLINE | ID: mdl-38582872

ABSTRACT

Acyl-CoA binding protein (ACBP) encoded by diazepam binding inhibitor (DBI) is an extracellular inhibitor of autophagy acting on the gamma-aminobutyric acid A receptor (GABAAR) γ2 subunit (GABAARγ2). Here, we show that lipoanabolic diets cause an upregulation of GABAARγ2 protein in liver hepatocytes but not in other major organs. ACBP/DBI inhibition by systemically injected antibodies has been demonstrated to mediate anorexigenic and organ-protective, autophagy-dependent effects. Here, we set out to develop a new strategy for developing ACBP/DBI antagonists. For this, we built a molecular model of the interaction of ACBP/DBI with peptides derived from GABAARγ2. We then validated the interaction between recombinant and native ACBP/DBI protein and a GABAARγ2-derived eicosapeptide (but not its F77I mutant) by pull down experiments or surface plasmon resonance. The GABAARγ2-derived eicosapeptide inhibited the metabolic activation of hepatocytes by recombinant ACBP/DBI protein in vitro. Moreover, the GABAARγ2-derived eicosapeptide (but not its F77I-mutated control) blocked appetite stimulation by recombinant ACBP/DBI in vivo, induced autophagy in the liver, and protected mice against the hepatotoxin concanavalin A. We conclude that peptidomimetics disrupting the interaction between ACBP/DBI and GABAARγ2 might be used as ACBP/DBI antagonists. This strategy might lead to the future development of clinically relevant small molecules of the ACBP/DBI system.


Subject(s)
Diazepam Binding Inhibitor , gamma-Aminobutyric Acid , Animals , Mice , Diazepam Binding Inhibitor/pharmacology
2.
Methods Mol Biol ; 2769: 1-13, 2024.
Article in English | MEDLINE | ID: mdl-38315385

ABSTRACT

Orthotopic models of hepatocellular carcinoma (HCC) consist in the implantation of tumor cells into the liver by direct intrahepatic injection. In this model, tumorigenesis is triggered within the hepatic microenvironment, thus mimicking the metastatic behavior of HCC. Herein, we detail a surgically mediated methodology that allows the reproducible and effective induction of liver-sessile tumors in mice. We enumerate the steps to be followed before and after the surgical procedure, including HCC cell preparation, the quantity of cancer cells to be injected, presurgical preparation of the mice, and finally, postoperative care. The surgical procedure involves laparotomy to expose the liver, injection of cells into the left-lateral hepatic lobe, and closure of the incision with sutures followed by wound clips. We also provide information concerning the subsequent tumor growth follow-up, as well as the application of bioluminescence imaging to monitor tumor development.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Mice , Animals , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Cell Line , Diagnostic Imaging , Cell Line, Tumor , Disease Models, Animal , Tumor Microenvironment
3.
Methods Mol Biol ; 2769: 57-65, 2024.
Article in English | MEDLINE | ID: mdl-38315388

ABSTRACT

Non-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease (NAFLD). Obesity is a known risk factor of NASH, which, in turn, increases the risk of developing cirrhosis (liver scarring) and hepatocellular carcinoma (HCC). In addition to being a potentially life-threatening condition, public health concerns surrounding NASH are amplified by the lack of FDA-approved treatments. Although various preclinical models reflecting both the histopathology and the pathophysiological progression of human NASH exist, most of these models are diet-based and require 6-13 months for NASH symptom manifestation. Here, we describe a simple and rapid-progression model of NASH and NASH-driven HCC in mice. Mice received a western diet equivalent (WD; i.e., a high-fat, high-fructose, and high-cholesterol diet), high-sugar water (23.1 g/L fructose and 18.9 g/L glucose), and weekly intraperitoneal injections of carbon tetrachloride (CCl4) at a dose of 0.2 µL/g of body weight. The resulting phenotype, consisting in liver fibrosis and HCC, appeared within 24 weeks of diet/treatment initiation and presented similar histological and transcriptomic features as human NASH and NASH-driven HCC, thereby supporting the adequacy of this preclinical model for the development and evaluation of drugs that can prevent or reverse these diseases.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Non-alcoholic Fatty Liver Disease , Humans , Mice , Animals , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/pathology , Carcinoma, Hepatocellular/genetics , Carbon Tetrachloride/toxicity , Liver Neoplasms/pathology , Diet, Western/adverse effects , Disease Models, Animal , Liver Cirrhosis/pathology , Fructose , Diet, High-Fat/adverse effects , Liver/pathology , Mice, Inbred C57BL
4.
Methods Mol Biol ; 2769: 67-75, 2024.
Article in English | MEDLINE | ID: mdl-38315389

ABSTRACT

Hepatocellular carcinoma (HCC) is the most common type of liver cancer and the second most common cause of cancer-related death. HCC is associated to chronic diseases such as viral hepatitis, alcoholic, and non-alcoholic fatty liver disease (NAFLD), diabetes mellitus, and obesity, among others. Although pre-clinical models have been investigated to mimic the transition from NAFLD to HCC, they do not accurately reproduce the phenotypic evolution from simple steatosis to steatohepatitis, fibrosis/cirrhosis, and HCC. Hence, these models have failed to demonstrate the influence of diabetes on hepatic carcinogenesis. Here, we report a novel mouse model of HCC triggered by fast-developing diabetes and NAFLD. The first step consists in a single intraperitoneal injection of a low dose of streptozotocin into neonatal C57BL/6J mice to induce type 2 diabetes. In a second step, mice are fed with high-fat diet to accelerate the development of simple steatosis. Continuous high-fat diet exacerbates hepatic fat deposition with increased lobular inflammation (by activation of foam cell-like macrophages) and fibrosis (by activating hepatic stellate cells), two representative pathological traits of steatohepatitis/fibrosis. After 20 weeks, all mice developed multiple HCCs. This model of hepatic carcinogenesis triggered by diabetes mellitus and NAFLD offers the advantage of being rapid and accurately recapitulates the pathogenesis of human HCC without the need of administering hepatic carcinogens.


Subject(s)
Carcinoma, Hepatocellular , Diabetes Mellitus, Type 2 , Liver Neoplasms , Non-alcoholic Fatty Liver Disease , Humans , Mice , Animals , Carcinoma, Hepatocellular/etiology , Carcinoma, Hepatocellular/pathology , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/pathology , Liver Neoplasms/etiology , Liver Neoplasms/pathology , Streptozocin , Diet, High-Fat/adverse effects , Diabetes Mellitus, Type 2/pathology , Mice, Inbred C57BL , Liver/pathology , Disease Models, Animal , Liver Cirrhosis/pathology , Carcinogenesis/pathology
5.
Methods Mol Biol ; 2769: 189-198, 2024.
Article in English | MEDLINE | ID: mdl-38315398

ABSTRACT

The metabolic rearrangements of hepatic metabolism associated with liver cancer are still incompletely understood. There is an ongoing need to identify novel and more efficient diagnostic biomarkers and therapeutic targets based on the metabolic mechanisms of these diseases. In comparison to traditional diagnostic biomarkers, metabolomics is a comprehensive technique for discovering chemical signatures for liver cancer screening, prediction, and earlier diagnosis. Lipids are a large and diverse group of complex biomolecules that are at the heart of liver physiology and play an important role in the development and progression of cancer. In this chapter, we described two detailed protocols for targeted lipids analysis: glycerophospholipids and mono, di, tri-acylglycerides, both by Flow Injection Analysis (FIA) HPLC coupled to a SelexIon/QTRAP 6500+ system. These approaches provide a targeted lipidomic metabolomic signature of dissimilar metabolic disorders affecting liver cancers.


Subject(s)
Glycerophospholipids , Liver Neoplasms , Humans , Metabolomics/methods , Biomarkers
6.
Methods Mol Biol ; 2769: 109-128, 2024.
Article in English | MEDLINE | ID: mdl-38315393

ABSTRACT

In the early stages of liver carcinogenesis, rare hepatocytes and cholangiocytes are transformed into preneoplastic cells, which can progressively acquire a neoplastic phenotype, favored by the failure of natural antitumor immunosurveillance. The detailed study of both hepatic parenchymal (e.g., hepatocytes) and non-parenchymal cells (NPCs), such as immune cells, could help understand the cellular microenvironment surrounding these pre-cancerous and neoplastic lesions.Cultures of primary hepatocytes are of interest in various biomedical research disciplines, serving as an ex vivo model for liver physiology. Obtaining high viability and yield of primary mouse hepatocytes and other liver cell populations is technically challenging, thus limiting their use. In the first section of the current chapter, we introduce a protocol based on the two-step collagenase perfusion technique (by inferior vena cava) to isolate hepatocytes and, to a lower extent, NPCs and detailed the different considerations to take into account for a successful perfusion. The liver is washed by perfusion, hepatocytes are dissociated with collagenase, and different cell populations are separated by centrifugation. Various techniques have been described for the isolation of healthy and malignant hepatocytes; however, the viability and purity of the isolated cells is frequently not satisfactory. Here, we significantly optimized this protocol to reach improved yield and viability of the hepatocytes and concomitantly obtain preserved NPC populations of the liver.Within NPCs, tissue-resident or recruited immune cells are essential actors regulating hepatocarcinogenesis. However, simultaneous isolation of hepatic leukocytes together with other cell types generally yields low immune cell numbers hindering downstream application with these cells. In the second section of this chapter, as opposed to the first section primarily aiming to isolate hepatocytes, we present a tissue dissociation protocol adapted to efficiently recover leukocytes from non-perfused bulk (pre-)cancerous livers. This protocol has been optimized to be operator-friendly and fast compared to other liver processing methods, allowing easy simultaneous sample processing to retrieve hepatic (tumor-infiltrating) immune cells.


Subject(s)
Liver , Precancerous Conditions , Mice , Animals , Cell Separation/methods , Hepatocytes , Carcinogenesis , Collagenases , Tumor Microenvironment
7.
Methods Mol Biol ; 2769: 199-209, 2024.
Article in English | MEDLINE | ID: mdl-38315399

ABSTRACT

Liver cancers are characterized by interindividual and intratumoral heterogeneity, which makes early diagnosis and the development of therapies challenging. Desorption electrospray ionization mass spectrometry (DESI-MS) imaging is a potent and sensitive MS ionization technique for direct, unaltered 2D and 3D imaging of metabolites in complex biological samples. Indeed, DESI gently desorbs and ionizes analyte molecules from the sample surface using an electrospray source of highly charged aqueous spray droplets in ambient conditions. DESI-MS imaging of biological samples allows untargeted analysis and characterization of metabolites in liver cancers to identify new biomarkers of malignancy. In this chapter, we described a detailed protocol using liver cancer samples collected and stored for histopathology examination, either as frozen or as formalin-fixed, paraffin-embedded specimens. Such hepatocellular carcinoma samples can be subjected to DESI-MS analyses, illustrating the capacity of spatially resolved metabolomics to distinguish malignant lesions from adjacent normal liver tissue.


Subject(s)
Liver Neoplasms , Spectrometry, Mass, Electrospray Ionization , Humans , Spectrometry, Mass, Electrospray Ionization/methods , Metabolomics , Liver Neoplasms/diagnostic imaging , Biomarkers
8.
Mol Cancer ; 22(1): 128, 2023 08 10.
Article in English | MEDLINE | ID: mdl-37563591

ABSTRACT

Protein regulator of cytokinesis 1 (PRC1) is involved in cytokinesis. Growing evidence suggests the association of PRC1 with multiple cancers. Here, we unveil that, in 28 cancer types, PRC1 is higher expressed in tumor tissues than in non-malignant tissues. Overexpression of PRC1 indicates unfavorable prognostic value, especially in ACC, LGG, KIRP, LICH, LUAD, MESO, PAAD, SARC and UCEC, while methylation of the PRC1 gene at sites associated with its inactivation has a favorable prognostic value in ACC, KIRP, LUAD, MESO, KIRP and LGG. Differentially expressed genes (DEGs) associated with high (> median) PRC1 expression contribute to key signaling pathways related with cell cycle, DNA damage and repair, EMT, cell migration, invasion and cell proliferation in most cancer types. More specifically, the DEGs involved in RAS/RAF/MAPK, PI3K/AKT, WNT, NOTCH, TGF-ß, integrin, EMT process, focal adhesion, RHO GTPase-related pathway or microtubule cytoskeleton regulation are upregulated when PRC1 expression is above median, as confirmed for most cancers. Most importantly, high expression of PRC1 appears to be associated with an overabundance of poor-prognosis TH2 cells. Furthermore, positive correlations of PRC1 and some immune checkpoint genes (CD274, CTLA4, HAVCR2, LAG3, PDCD1, PDCD1LG2, TIGIT, and CD86) were observed in several cancers, especially BLCA, BRCA, KIRC, LUAD, LIHC, PRAD and THCA. These findings plead in favor of further studies validating the diagnostic and prognostic impact of PRC1 as well as the elaboration of pharmacological strategies for targeting PRC1.


Subject(s)
Cytokinesis , Neoplasms , Humans , Phosphatidylinositol 3-Kinases , Neoplasms/genetics , Cell Proliferation , Signal Transduction
9.
J Phys Chem B ; 127(21): 4733-4745, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37195090

ABSTRACT

Coherent anti-Stokes Raman scattering (CARS) microscopy is an emerging nonlinear vibrational imaging technique that delivers label-free chemical maps of cells and tissues. In narrowband CARS, two spatiotemporally superimposed picosecond pulses, pump and Stokes, illuminate the sample to interrogate a single vibrational mode. Broadband CARS (BCARS) combines narrowband pump pulses with broadband Stokes pulses to record broad vibrational spectra. Despite recent technological advancements, BCARS microscopes still struggle to image biological samples over the entire Raman-active region (400-3100 cm-1). Here, we demonstrate a robust BCARS platform that answers this need. Our system is based on a femtosecond ytterbium laser at a 1035 nm wavelength and a 2 MHz repetition rate, which delivers high-energy pulses used to produce broadband Stokes pulses by white-light continuum generation in a bulk YAG crystal. Combining such pulses, pre-compressed to sub-20 fs duration, with narrowband pump pulses, we generate a CARS signal with a high (<9 cm-1) spectral resolution in the whole Raman-active window, exploiting both the two-color and three-color excitation mechanisms. Aided by an innovative post-processing pipeline, our microscope allows us to perform high-speed (≈1 ms pixel dwell time) imaging over a large field of view, identifying the main chemical compounds in cancer cells and discriminating tumorous from healthy regions in liver slices of mouse models, paving the way for applications in histopathological settings.


Subject(s)
Light , Microscopy , Animals , Mice , Spectrum Analysis, Raman/methods , Nonlinear Optical Microscopy , Lasers
10.
Aging Cell ; 22(1): e13751, 2023 01.
Article in English | MEDLINE | ID: mdl-36510662

ABSTRACT

Autophagy defects accelerate aging, while stimulation of autophagy decelerates aging. Acyl-coenzyme A binding protein (ACBP), which is encoded by a diazepam-binding inhibitor (DBI), acts as an extracellular feedback regulator of autophagy. As shown here, knockout of the gene coding for the yeast orthologue of ACBP/DBI (ACB1) improves chronological aging, and this effect is reversed by knockout of essential autophagy genes (ATG5, ATG7) but less so by knockout of an essential mitophagy gene (ATG32). In humans, ACBP/DBI levels independently correlate with body mass index (BMI) as well as with chronological age. In still-healthy individuals, we find that high ACBP/DBI levels correlate with future cardiovascular events (such as heart surgery, myocardial infarction, and stroke), an association that is independent of BMI and chronological age, suggesting that ACBP/DBI is indeed a biomarker of "biological" aging. Concurringly, ACBP/DBI plasma concentrations correlate with established cardiovascular risk factors (fasting glucose levels, systolic blood pressure, total free cholesterol, triglycerides), but are inversely correlated with atheroprotective high-density lipoprotein (HDL). In mice, neutralization of ACBP/DBI through a monoclonal antibody attenuates anthracycline-induced cardiotoxicity, which is a model of accelerated heart aging. In conclusion, plasma elevation of ACBP/DBI constitutes a novel biomarker of chronological aging and facets of biological aging with a prognostic value in cardiovascular disease.


Subject(s)
Cardiovascular Diseases , Carrier Proteins , Animals , Humans , Mice , Cardiovascular Diseases/genetics , Coenzyme A/metabolism , Diazepam Binding Inhibitor/genetics , Diazepam Binding Inhibitor/metabolism , Nuclear Proteins/metabolism
11.
Autophagy ; 19(5): 1604-1606, 2023 05.
Article in English | MEDLINE | ID: mdl-36198092

ABSTRACT

DBI/ACBP (diazepam binding inhibitor, also known as acyl coenzyme A binding protein), acts as a paracrine inhibitor of macroautophagy/autophagy. We characterized a monoclonal antibody neutralizing mouse DBI/ACBP (a-DBI) for its cytoprotective effects on several organs (heart, liver and lung) that were damaged by surgical procedures (ligation of coronary and hepatic arteries or bile duct ligation), a variety of different toxins (acetaminophen, bleomycin, carbon tetrachloride or concanavalin A) or a methionine/choline-deficient diet (MCD). In all these models of organ damage, a-DBI prevents cell loss, inflammation and fibrosis through pathways that are blocked by pharmacological or genetic inhibition of autophagy. The hepatoprotective effects of a-DBI against MCD are mimicked by three alternative strategies to block DBI/ACBP signaling, in particular (i) induction of DBI/ACBP-specific autoantibodies, (ii) tamoxifen-inducible knockout of the Dbi gene, and (iii) a point mutation in Gabrg2 (gamma-aminobutyric acid A receptor, subunit gamma 2; Gabrg2F77I) that abolishes binding of DBI/ACBP. We conclude that a-DBI-mediated neutralization of extracellular DBI/ACBP mediates potent autophagy-dependent organ protection by on-target effects, hence unraveling a novel and potentially useful strategy for autophagy enhancement. "Autophagy checkpoint inhibition" can be achieved by targeting DBI/ACBP.


Subject(s)
Autophagy , Macroautophagy , Mice , Animals
12.
Proc Natl Acad Sci U S A ; 119(41): e2207344119, 2022 10 11.
Article in English | MEDLINE | ID: mdl-36191214

ABSTRACT

Acyl-coenzyme A (CoA)-binding protein (ACBP), also known as diazepam-binding inhibitor (DBI), is an extracellular feedback regulator of autophagy. Here, we report that injection of a monoclonal antibody neutralizing ACBP/DBI (α-DBI) protects the murine liver against ischemia/reperfusion damage, intoxication by acetaminophen and concanavalin A, and nonalcoholic steatohepatitis caused by methionine/choline-deficient diet as well as against liver fibrosis induced by bile duct ligation or carbon tetrachloride. α-DBI downregulated proinflammatory and profibrotic genes and upregulated antioxidant defenses and fatty acid oxidation in the liver. The hepatoprotective effects of α-DBI were mimicked by the induction of ACBP/DBI-specific autoantibodies, an inducible Acbp/Dbi knockout or a constitutive Gabrg2F77I mutation that abolishes ACBP/DBI binding to the GABAA receptor. Liver-protective α-DBI effects were lost when autophagy was pharmacologically blocked or genetically inhibited by knockout of Atg4b. Of note, α-DBI also reduced myocardium infarction and lung fibrosis, supporting the contention that it mediates broad organ-protective effects against multiple insults.


Subject(s)
Diazepam Binding Inhibitor , Receptors, GABA-A , Animals , Mice , Acetaminophen , Antibodies, Monoclonal/metabolism , Antioxidants , Autoantibodies/metabolism , Autophagy , Carbon Tetrachloride , Carrier Proteins/genetics , Choline , Coenzyme A/metabolism , Concanavalin A/metabolism , Diazepam , Diazepam Binding Inhibitor/metabolism , Fatty Acids/metabolism , Fibrosis , Inflammation , Methionine
14.
Cell Death Dis ; 13(4): 356, 2022 04 18.
Article in English | MEDLINE | ID: mdl-35436993

ABSTRACT

Acyl-coenzyme-A-binding protein (ACBP), also known as a diazepam-binding inhibitor (DBI), is a potent stimulator of appetite and lipogenesis. Bioinformatic analyses combined with systematic screens revealed that peroxisome proliferator-activated receptor gamma (PPARγ) is the transcription factor that best explains the ACBP/DBI upregulation in metabolically active organs including the liver and adipose tissue. The PPARγ agonist rosiglitazone-induced ACBP/DBI upregulation, as well as weight gain, that could be prevented by knockout of Acbp/Dbi in mice. Moreover, liver-specific knockdown of Pparg prevented the high-fat diet (HFD)-induced upregulation of circulating ACBP/DBI levels and reduced body weight gain. Conversely, knockout of Acbp/Dbi prevented the HFD-induced upregulation of PPARγ. Notably, a single amino acid substitution (F77I) in the γ2 subunit of gamma-aminobutyric acid A receptor (GABAAR), which abolishes ACBP/DBI binding to this receptor, prevented the HFD-induced weight gain, as well as the HFD-induced upregulation of ACBP/DBI, GABAAR γ2, and PPARγ. Based on these results, we postulate the existence of an obesogenic feedforward loop relying on ACBP/DBI, GABAAR, and PPARγ. Interruption of this vicious cycle, at any level, indistinguishably mitigates HFD-induced weight gain, hepatosteatosis, and hyperglycemia.


Subject(s)
Diazepam Binding Inhibitor , Receptors, GABA-A , Animals , Carrier Proteins , Coenzyme A/metabolism , Diazepam Binding Inhibitor/genetics , Diazepam Binding Inhibitor/metabolism , Mice , PPAR gamma/genetics , PPAR gamma/metabolism , Receptors, GABA/metabolism , Receptors, GABA-A/genetics , Receptors, GABA-A/metabolism , Weight Gain , gamma-Aminobutyric Acid
15.
Cytokine ; 133: 155172, 2020 09.
Article in English | MEDLINE | ID: mdl-32590329

ABSTRACT

IFN-α administration to patients has been long discouraged and pushed back by new and apparently better drugs; however the adverse secondary effect, the high costs and the lack of specific action, make these new drugs hard to be used and put IFN-α again in the eye of the researchers. IFN-α-2b was demonstrated to induce apoptosis and modulation of lipid metabolism and the mechanisms are still unknown. Here, we sought to find the link between these features using a model of early stage cancer development. Using in vitro and in vivo approaches, we evaluated apoptosis and lipid metabolism. IFN-α-2b induced changes in hepatic cholesterol mass due to decreased synthesis and increased secretion. Interestingly, the drop in cellular cholesterol levels was necessary for IFN-α-2b to induce apoptosis. Results presented in this paper show the complexity of the action of IFN-α-2b on the early stages of liver cancer development. We show for the first time an interrelationship between cholesterol, apoptosis and IFN-α-2b. This makes clear the need for a reevaluation of IFN-α-2b action in order to develop softer, safer and more bearable derivatives. In this regard, knowing the molecular mechanisms by which IFN-α exerts its cellular actions is of crucial importance, and it is the main condition for therapy success for classical and new malignancies.


Subject(s)
Apoptosis/drug effects , Cholesterol/metabolism , Hepatocytes/drug effects , Interferon alpha-2/pharmacology , Animals , Cell Line, Tumor , Hepatocytes/metabolism , Humans , Lipid Metabolism/drug effects , Liver/drug effects , Liver/metabolism , Liver Neoplasms/metabolism , Male , Rats , Rats, Wistar
16.
J Nutr Biochem ; 58: 17-27, 2018 08.
Article in English | MEDLINE | ID: mdl-29860102

ABSTRACT

Obesity is accompanied by a low-grade inflammation state, characterized by increased proinflammatory cytokines levels such as tumor necrosis factor alpha (TNFα) and interleukin-1 beta (IL-1ß). In this regard, there exists a lack of studies in hepatic tissue about the role of TNFα receptor 1 (TNFR1) in the context of obesity and insulin resistance during the progression of nonalcoholic fatty liver disease (NAFLD). The aim of this work was to evaluate the effects of high-caloric feeding (HFD) (40% fat, for 16 weeks) on liver inflammation-induced apoptosis, insulin resistance, hepatic lipid accumulation and its progression toward nonalcoholic steatohepatitis (NASH) in TNFR1 knock-out and wild-type mice. Mechanisms involved in HFD-derived IL-1ß release and impairment of insulin signaling are still unknown, so we determined whether IL-1ß affects liver insulin sensitivity and apoptosis through TNFα receptor 1 (TNFR1)-dependent pathways. We showed that knocking out TNFR1 induces an enhanced IL-1ß plasmatic release upon HFD feed. This was correlated with higher hepatic and epididymal white adipose tissue mRNA levels. In vivo and in vitro assays confirmed an impairment in hepatic insulin signaling, in part due to IL-1ß-induced decrease of AKT activation and diminution of IRS1 levels, followed by an increase in inflammation, macrophage (resident and recruited) accumulation, hepatocyte apoptotic process and finally hepatic damage. In addition, TNFR1 KO mice displayed higher levels of pro-fibrogenic markers. TNFR1 signaling disruption upon an HFD leads to an accelerated progression from simple steatosis to a more severe phenotype with many NASH features, pointing out a key role of TNFR1 in NAFLD progression.


Subject(s)
Diet, High-Fat/adverse effects , Non-alcoholic Fatty Liver Disease/etiology , Receptors, Tumor Necrosis Factor, Type I/metabolism , Animals , Apoptosis/genetics , Insulin/metabolism , Insulin Resistance , Interleukin-1beta/metabolism , Liver/metabolism , Liver/pathology , Macrophages/metabolism , Macrophages/pathology , Male , Mice, Inbred C57BL , Mice, Knockout , Non-alcoholic Fatty Liver Disease/pathology , Receptors, Tumor Necrosis Factor, Type I/genetics , Signal Transduction
17.
Toxicol Lett ; 289: 63-74, 2018 Jun 01.
Article in English | MEDLINE | ID: mdl-29545174

ABSTRACT

Sirtuins (SIRTs) 1 and 2 deacetylases are overexpressed in hepatocellular carcinoma (HCC) and are associated with tumoral progression and multidrug resistance (MDR). In this study we analyzed whether SIRTs 1 and 2 activities blockage was able to affect cellular survival and migration and to modulate p53 and FoxO1 acetylation in HepG2 and Huh7 cells. Moreover, we analyzed ABC transporters P-glycoprotein (P-gp) and multidrug resistance-associated protein 3 (MRP3) expression. We used cambinol and EX-527 as SIRTs inhibitors. Both drugs reduced cellular viability, number of colonies and cellular migration and augmented apoptosis. In 3D cultures, SIRTs inhibitors diminished spheroid growth and viability. 3D culture was less sensitive to drugs than 2D culture. The levels of acetylated p53 and FoxO1 increased after treatments. Drugs induced a decrease in ABC transporters mRNA and protein levels in HepG2 cells; however, only EX-527 was able to reduce MRP3 mRNA and protein levels in Huh7 cells. This is the first work demonstrating the regulation of MRP3 by SIRTs. In conclusion, both drugs decreased HCC cells survival and migration, suggesting SIRTs 1 and 2 activities blockage could be beneficial during HCC therapy. Downregulation of the expression of P-gp and MRP3 supports the potential application of SIRTs 1 and 2 inhibitions in combination with conventional chemotherapy.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B/metabolism , Carcinoma, Hepatocellular/drug therapy , Histone Deacetylase Inhibitors/pharmacology , Liver Neoplasms/drug therapy , Multidrug Resistance-Associated Proteins/metabolism , Sirtuin 1/antagonists & inhibitors , Sirtuin 2/antagonists & inhibitors , ATP Binding Cassette Transporter, Subfamily B/antagonists & inhibitors , ATP Binding Cassette Transporter, Subfamily B/genetics , Acetylation/drug effects , Antineoplastic Agents/pharmacology , Carbazoles/pharmacology , Carcinoma, Hepatocellular/enzymology , Carcinoma, Hepatocellular/metabolism , Cell Line, Tumor , Cell Movement/drug effects , Cell Survival/drug effects , Drug Resistance, Multiple , Drug Resistance, Neoplasm , Gene Expression Regulation, Neoplastic/drug effects , Humans , Liver Neoplasms/enzymology , Liver Neoplasms/metabolism , Multidrug Resistance-Associated Proteins/antagonists & inhibitors , Multidrug Resistance-Associated Proteins/genetics , Naphthalenes/pharmacology , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Protein Processing, Post-Translational/drug effects , Pyrimidinones/pharmacology , Sirtuin 1/metabolism , Sirtuin 2/metabolism
18.
Brain Behav Immun ; 65: 284-295, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28666938

ABSTRACT

Earlier studies from our laboratory demonstrated that acute experimental Trypanosoma cruzi infection promotes an intense inflammation along with a sepsis-like dysregulated adrenal response characterized by normal levels of ACTH with raised glucocorticoid secretion. Inflammation was also known to result in adrenal cell apoptosis, which in turn may influence HPA axis uncoupling. To explore factors and pathways which may be involved in the apoptosis of adrenal cells, together with its impact on the functionality of the gland, we carried out a series of studies in mice lacking death receptors, such as TNF-R1 (C57BL/6-Tnfrsf1a tm1Imx or TNF-R1-/-) or Fas ligand (C57BL/6 Fas-deficient lpr mice), undergoing acute T. cruzi infection. Here we demonstrate that the late hypercorticosterolism seen in C57BL/6 mice during acute T. cruzi infection coexists with and hyperplasia and hypertrophy of zona fasciculata, paralleled by increased number of apoptotic cells. Apoptosis seems to be mediated mainly by the type II pathway of Fas-mediated apoptosis, which engages the mitochondrial pathway of apoptosis triggering the cytochrome c release to increase caspase-3 activation. Fas-induced apoptosis of adrenocortical cells is also related with an exacerbated production of intra-adrenal cytokines that probably maintain the late supply of adrenal hormones during host response. Present results shed light on the molecular mechanisms dealing with these phenomena which are crucial not only for the development of interventions attempting to avoid adrenal dysfunction, but also for its wide occurrence in other infectious-based critical illnesses.


Subject(s)
Adrenal Cortex/physiopathology , Receptors, Tumor Necrosis Factor, Type I/physiology , fas Receptor/physiology , Adrenal Cortex/microbiology , Animals , Apoptosis/immunology , Apoptosis/physiology , Caspase 3/metabolism , Cytokines/metabolism , Fas Ligand Protein/metabolism , Fas Ligand Protein/physiology , Glucocorticoids/metabolism , Hypothalamo-Hypophyseal System/metabolism , Inflammation , Mice , Mice, Inbred C57BL , Pituitary-Adrenal System/metabolism , Receptors, Tumor Necrosis Factor, Type I/metabolism , Signal Transduction , Trypanosoma cruzi/pathogenicity , Tumor Necrosis Factor-alpha/metabolism , fas Receptor/metabolism
19.
Toxicol Appl Pharmacol ; 315: 12-22, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-27899278

ABSTRACT

Molecular mechanisms on sepsis progression are linked to the imbalance between reactive oxygen species (ROS) production and cellular antioxidant capacity. Previous studies demonstrated that benznidazole (BZL), known for its antiparasitic action on Trypanosoma cruzi, has immunomodulatory effects, increasing survival in C57BL/6 mice in a model of polymicrobial sepsis induced by cecal ligation and puncture (CLP). The mechanism by which BZL inhibits inflammatory response in sepsis is poorly understood. Also, our group recently reported that BZL is able to activate the nuclear factor erytroide-derived 2-Like 2 (NRF2) in vitro. The aim of the present work was to delineate the beneficial role of BZL during sepsis, analyzing its effects on the cellular redox status and the possible link to the innate immunity receptor TLR4. Specifically, we analyzed the effect of BZL on Nrf2 regulation and TLR4 expression in liver of mice 24hours post-CLP. BZL was able to induce NRF2 nuclear protein localization in CLP mice. Also, we found that protein kinase C (PKC) is involved in the NRF2 nuclear accumulation and induction of its target genes. In addition, BZL prompted a reduction in hepatic CLP-induced TLR4 protein membrane localization, evidencing its immunomodulatory effects. Together, our results demonstrate that BZL induces hepatic NRF2 activation with the concomitant increase in the antioxidant defenses, and the attenuation of inflammatory response, in part, by inhibiting TLR4 expression in a murine model of sepsis.


Subject(s)
Chagas Disease/drug therapy , Disease Models, Animal , Inflammation/prevention & control , Liver/drug effects , NF-E2-Related Factor 2/metabolism , Nitroimidazoles/pharmacology , Sepsis/drug therapy , Trypanocidal Agents/pharmacology , Animals , Antioxidants/metabolism , Down-Regulation/drug effects , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , NF-E2-Related Factor 2/genetics , Nitroimidazoles/therapeutic use , Oxidative Stress , Toll-Like Receptor 4/metabolism , Trypanocidal Agents/therapeutic use
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