195 results on '"Gilardi, F."'
Search Results
152. LT175 is a novel PPARα/γ ligand with potent insulin-sensitizing effects and reduced adipogenic properties.
- Author
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Gilardi F, Giudici M, Mitro N, Maschi O, Guerrini U, Rando G, Maggi A, Cermenati G, Laghezza A, Loiodice F, Pochetti G, Lavecchia A, Caruso D, De Fabiani E, Bamberg K, and Crestani M
- Subjects
- 3T3-L1 Cells, Animals, Biphenyl Compounds metabolism, Blood Glucose drug effects, Body Weight drug effects, Diabetes Mellitus, Type 2 drug therapy, Dyslipidemias drug therapy, Glucose metabolism, Glucose Tolerance Test, Hypoglycemic Agents metabolism, Insulin blood, Ligands, Lipid Metabolism drug effects, Male, Mice, Mice, Inbred C57BL, Nuclear Receptor Co-Repressor 1 metabolism, PPAR alpha metabolism, PPAR gamma metabolism, Phenylpropionates metabolism, Adipogenesis drug effects, Biphenyl Compounds administration & dosage, Hypoglycemic Agents pharmacology, Insulin pharmacology, Insulin Resistance, PPAR alpha agonists, PPAR gamma agonists, Phenylpropionates administration & dosage
- Abstract
Peroxisome proliferator-activated receptors (PPARs) are ligand-dependent transcription factors regulating lipid and glucose metabolism. Ongoing drug discovery programs aim to develop dual PPARα/γ agonists devoid of the side effects of the marketed antidiabetic agents thiazolidinediones and the dual agonists glitazars. Recently, we described a new dual PPARα/γ ligand, LT175, with a partial agonist profile against PPARγ and interacting with a newly identified region of the PPARγ-ligand binding domain (1). Here we show that LT175 differentially activated PPARγ target genes involved in fatty acid esterification and storage in 3T3-L1-derived adipocytes. This resulted in a less severe lipid accumulation compared with that triggered by rosiglitazone, suggesting that LT175 may have a lower adipogenic activity. Consistent with this hypothesis, in vivo administration of LT175 to mice fed a high-fat diet decreased body weight, adipocyte size, and white adipose tissue mass, as assessed by magnetic resonance imaging. Furthermore, LT175 significantly reduced plasma glucose, insulin, non-esterified fatty acids, triglycerides, and cholesterol and increased circulating adiponectin and fibroblast growth factor 21 levels. Oral glucose and insulin tolerance tests showed that the compound improves glucose homeostasis and insulin sensitivity. Moreover, we demonstrate that the peculiar interaction of LT175 with PPARγ affected the recruitment of the coregulators cyclic-AMP response element-binding protein-binding protein and nuclear corepressor 1 (NCoR1), fundamentals for the PPARγ-mediated adipogenic program. In conclusion, our results describe a new PPAR ligand, modulating lipid and glucose metabolism with reduced adipogenic activity, that may be used as a model for a series of novel molecules with an improved pharmacological profile for the treatment of dyslipidemia and type 2 diabetes.
- Published
- 2014
- Full Text
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153. Genome-wide analysis of SREBP1 activity around the clock reveals its combined dependency on nutrient and circadian signals.
- Author
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Gilardi F, Migliavacca E, Naldi A, Baruchet M, Canella D, Le Martelot G, Guex N, and Desvergne B
- Subjects
- Animals, Binding Sites, CLOCK Proteins genetics, Circadian Clocks physiology, Circadian Rhythm physiology, Gene Expression Regulation, Genome, Hepatocyte Nuclear Factor 4 genetics, Hepatocyte Nuclear Factor 4 metabolism, Homeostasis, Mice, Protein Binding, Circadian Clocks genetics, Circadian Rhythm genetics, Lipid Metabolism genetics, Sterol Regulatory Element Binding Protein 1 genetics
- Abstract
In mammals, the circadian clock allows them to anticipate and adapt physiology around the 24 hours. Conversely, metabolism and food consumption regulate the internal clock, pointing the existence of an intricate relationship between nutrient state and circadian homeostasis that is far from being understood. The Sterol Regulatory Element Binding Protein 1 (SREBP1) is a key regulator of lipid homeostasis. Hepatic SREBP1 function is influenced by the nutrient-response cycle, but also by the circadian machinery. To systematically understand how the interplay of circadian clock and nutrient-driven rhythm regulates SREBP1 activity, we evaluated the genome-wide binding of SREBP1 to its targets throughout the day in C57BL/6 mice. The recruitment of SREBP1 to the DNA showed a highly circadian behaviour, with a maximum during the fed status. However, the temporal expression of SREBP1 targets was not always synchronized with its binding pattern. In particular, different expression phases were observed for SREBP1 target genes depending on their function, suggesting the involvement of other transcription factors in their regulation. Binding sites for Hepatocyte Nuclear Factor 4 (HNF4) were specifically enriched in the close proximity of SREBP1 peaks of genes, whose expression was shifted by about 8 hours with respect to SREBP1 binding. Thus, the cross-talk between hepatic HNF4 and SREBP1 may underlie the expression timing of this subgroup of SREBP1 targets. Interestingly, the proper temporal expression profile of these genes was dramatically changed in Bmal1-/- mice upon time-restricted feeding, for which a rhythmic, but slightly delayed, binding of SREBP1 was maintained. Collectively, our results show that besides the nutrient-driven regulation of SREBP1 nuclear translocation, a second layer of modulation of SREBP1 transcriptional activity, strongly dependent from the circadian clock, exists. This system allows us to fine tune the expression timing of SREBP1 target genes, thus helping to temporally separate the different physiological processes in which these genes are involved.
- Published
- 2014
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- View/download PDF
154. RXRs: collegial partners.
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Gilardi F and Desvergne B
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- Alitretinoin, Animals, Gene Expression Regulation, Humans, Ligands, Mice, Protein Binding, Protein Isoforms genetics, Protein Isoforms metabolism, Protein Multimerization, Protein Structure, Tertiary, Receptors, Retinoic Acid genetics, Response Elements, Retinoid X Receptors genetics, Signal Transduction, Tretinoin chemistry, Receptors, Retinoic Acid metabolism, Retinoid X Receptors metabolism, Tretinoin metabolism
- Abstract
Retinoid X Receptors (RXR) were initially identified as nuclear receptors binding with stereo-selectivity the vitamin A derivative 9-cis retinoic acid, although the relevance of this molecule as endogenous activator of RXRs is still elusive. Importantly, within the nuclear receptor superfamily, RXRs occupy a peculiar place, as they are obligatory partners for a number of other nuclear receptors, thus integrating the corresponding signaling pathways. In this chapter, we describe the structural features allowing RXR to form homo- and heterodimers, and the functional consequences of this unique ability. Furthermore, we discuss the importance of studying RXR activity at a genome-wide level in order to comprehensively address the biological implications of their action that is fundamental to understand to what extent RXRs could be exploited as new therapeutic targets.
- Published
- 2014
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155. Influenza vaccination coverage among medical residents: an Italian multicenter survey.
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Costantino C, Mazzucco W, Azzolini E, Baldini C, Bergomi M, Biafiore AD, Bianco M, Borsari L, Cacciari P, Cadeddu C, Camia P, Carluccio E, Conti A, De Waure C, Di Gregori V, Fabiani L, Fallico R, Filisetti B, Flacco ME, Franco E, Furnari R, Galis V, Gallea MR, Gallone MF, Gallone S, Gelatti U, Gilardi F, Giuliani AR, Grillo OC, Lanati N, Mascaretti S, Mattei A, Micò R, Morciano L, Nante N, Napoli G, Nobile CG, Palladino R, Parisi S, Passaro M, Pelissero G, Quarto M, Ricciardi W, Romano G, Rustico E, Saponari A, Schioppa FS, Signorelli C, Siliquini R, Trabacchi V, Triassi M, Varetta A, Ziglio A, Zoccali A, Vitale F, and Amodio E
- Subjects
- Adult, Female, Humans, Influenza, Human epidemiology, Influenza, Human prevention & control, Italy epidemiology, Male, Vaccination trends, Attitude of Health Personnel, Data Collection methods, Influenza Vaccines therapeutic use, Internship and Residency trends, Physicians trends, Vaccination statistics & numerical data
- Abstract
Although influenza vaccination is recognized to be safe and effective, recent studies have confirmed that immunization coverage among health care workers remain generally low, especially among medical residents (MRs). Aim of the present multicenter study was to investigate attitudes and determinants associated with acceptance of influenza vaccination among Italian MRs. A survey was performed in 2012 on MRs attending post-graduate schools of 18 Italian Universities. Each participant was interviewed via an anonymous, self-administered, web-based questionnaire including questions on attitudes regarding influenza vaccination. A total of 2506 MRs were recruited in the survey and 299 (11.9%) of these stated they had accepted influenza vaccination in 2011-2012 season. Vaccinated MRs were older (P = 0.006), working in clinical settings (P = 0.048), and vaccinated in the 2 previous seasons (P<0.001 in both seasons). Moreover, MRs who had recommended influenza vaccination to their patients were significantly more compliant with influenza vaccination uptake in 2011-2012 season (P<0.001). "To avoid spreading influenza among patients" was recognized as the main reason for accepting vaccination by less than 15% of vaccinated MRs. Italian MRs seem to have a very low compliance with influenza vaccination and they seem to accept influenza vaccination as a habit that is unrelated to professional and ethical responsibility. Otherwise, residents who refuse vaccination in the previous seasons usually maintain their behaviors. Promoting correct attitudes and good practice in order to improve the influenza immunization rates of MRs could represent a decisive goal for increasing immunization coverage among health care workers of the future.
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- 2014
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156. SOCS3 transactivation by PPARγ prevents IL-17-driven cancer growth.
- Author
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Berger H, Végran F, Chikh M, Gilardi F, Ladoire S, Bugaut H, Mignot G, Chalmin F, Bruchard M, Derangère V, Chevriaux A, Rébé C, Ryffel B, Pot C, Hichami A, Desvergne B, Ghiringhelli F, and Apetoh L
- Subjects
- Animals, Blotting, Western, CD4-Positive T-Lymphocytes drug effects, CD4-Positive T-Lymphocytes metabolism, Cell Differentiation drug effects, Cell Line, Tumor, Diet, Docosahexaenoic Acids administration & dosage, Docosahexaenoic Acids pharmacology, Female, Interleukin-17 metabolism, Mammary Neoplasms, Experimental pathology, Mammary Neoplasms, Experimental prevention & control, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Mice, Knockout, Mice, Nude, PPAR gamma agonists, PPAR gamma metabolism, Promoter Regions, Genetic genetics, RNA Interference, Reverse Transcriptase Polymerase Chain Reaction, Suppressor of Cytokine Signaling 3 Protein, Suppressor of Cytokine Signaling Proteins metabolism, Th17 Cells drug effects, Th17 Cells metabolism, Tumor Burden drug effects, Tumor Burden genetics, Mammary Neoplasms, Experimental genetics, PPAR gamma genetics, Suppressor of Cytokine Signaling Proteins genetics, Transcriptional Activation
- Abstract
Activation of the transcription factor PPARγ by the n-3 fatty acid docosahexaenoic acid (DHA) is implicated in controlling proinflammatory cytokine secretion, but the intracellular signaling pathways engaged by PPARγ are incompletely characterized. Here, we identify the adapter-encoding gene SOCS3 as a critical transcriptional target of PPARγ. SOCS3 promoter binding and gene transactivation by PPARγ was associated with a repression in differentiation of proinflammatory T-helper (TH)17 cells. Accordingly, TH17 cells induced in vitro displayed increased SOCS3 expression and diminished capacity to produce interleukin (IL)-17 following activation of PPARγ by DHA. Furthermore, naïve CD4 T cells derived from mice fed a DHA-enriched diet displayed less capability to differentiate into TH17 cells. In two different mouse models of cancer, DHA prevented tumor outgrowth and angiogenesis in an IL-17-dependent manner. Altogether, our results uncover a novel molecular pathway by which PPARγ-induced SOCS3 expression prevents IL-17-mediated cancer growth., (©2013 AACR.)
- Published
- 2013
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157. Molecular determinants for nuclear receptors selectivity: chemometric analysis, dockings and site-directed mutagenesis of dual peroxisome proliferator-activated receptors α/γ agonists.
- Author
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Carrieri A, Giudici M, Parente M, De Rosas M, Piemontese L, Fracchiolla G, Laghezza A, Tortorella P, Carbonara G, Lavecchia A, Gilardi F, Crestani M, and Loiodice F
- Subjects
- Algorithms, Amino Acid Sequence, Binding Sites genetics, Binding, Competitive, Clofibric Acid chemistry, Clofibric Acid pharmacology, Computer Simulation, Crystallography, X-Ray, Hep G2 Cells, Humans, Hypolipidemic Agents chemistry, Hypolipidemic Agents pharmacology, Ligands, Molecular Sequence Data, Molecular Structure, Mutagenesis, Site-Directed, PPAR alpha agonists, PPAR alpha genetics, PPAR gamma agonists, PPAR gamma genetics, Phenylacetates chemistry, Phenylacetates pharmacology, Quantitative Structure-Activity Relationship, Thermodynamics, Models, Molecular, PPAR alpha chemistry, PPAR gamma chemistry, Protein Structure, Tertiary
- Abstract
A series of previously synthesized chiral derivatives of clofibric and phenylacetic acids, acting as dual agonists towards the peroxisome proliferator-activated receptors (PPARs) α and γ, was taken into account, and the efficacy of these compounds was analyzed by means of 2D-, 3D-QSAR and docking studies with the goal to gain deeper insights into the three-dimensional determinants governing ligands selectivity for PPARs. By multiregressional analysis a correlation between the lipophilicity and PPARα activity was found, whereas for PPARγ the correlation was achieved once efficacy was related to the presence of polar groups on agonists scaffold. Docking of these compounds further corroborated this hypothesis, and then provided a valid support for subsequent chemometric analysis and pharmacophore models development for both receptors subtypes. Computational results suggested site directed mutagenesis experiments which confirmed the importance of amino acid residues in PPAR activity, allowing the identification of critical hotspots most likely taking over PPARs selectivity., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)
- Published
- 2013
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158. Inhibition of class I histone deacetylases unveils a mitochondrial signature and enhances oxidative metabolism in skeletal muscle and adipose tissue.
- Author
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Galmozzi A, Mitro N, Ferrari A, Gers E, Gilardi F, Godio C, Cermenati G, Gualerzi A, Donetti E, Rotili D, Valente S, Guerrini U, Caruso D, Mai A, Saez E, De Fabiani E, and Crestani M
- Subjects
- Adipose Tissue cytology, Adipose Tissue metabolism, Adipose Tissue ultrastructure, Animals, Anti-Obesity Agents pharmacology, Anti-Obesity Agents therapeutic use, Cell Line, Cells, Cultured, Diabetes Mellitus, Type 2 complications, Diabetes Mellitus, Type 2 drug therapy, Diabetes Mellitus, Type 2 metabolism, Diabetes Mellitus, Type 2 pathology, Histone Deacetylase 1 metabolism, Histone Deacetylase 2 antagonists & inhibitors, Histone Deacetylase 2 metabolism, Histone Deacetylase Inhibitors therapeutic use, Hypoglycemic Agents pharmacology, Hypoglycemic Agents therapeutic use, Male, Mice, Mice, Mutant Strains, Mitochondria, Muscle metabolism, Mitochondria, Muscle ultrastructure, Molecular Targeted Therapy, Muscle, Skeletal metabolism, Muscle, Skeletal ultrastructure, Obesity complications, Obesity drug therapy, Obesity metabolism, Obesity pathology, Random Allocation, Adipose Tissue drug effects, Energy Metabolism drug effects, Gene Expression Regulation drug effects, Histone Deacetylase 1 antagonists & inhibitors, Histone Deacetylase Inhibitors pharmacology, Mitochondria, Muscle drug effects, Muscle, Skeletal drug effects
- Abstract
Chromatin modifications are sensitive to environmental and nutritional stimuli. Abnormalities in epigenetic regulation are associated with metabolic disorders such as obesity and diabetes that are often linked with defects in oxidative metabolism. Here, we evaluated the potential of class-specific synthetic inhibitors of histone deacetylases (HDACs), central chromatin-remodeling enzymes, to ameliorate metabolic dysfunction. Cultured myotubes and primary brown adipocytes treated with a class I-specific HDAC inhibitor showed higher expression of Pgc-1α, increased mitochondrial biogenesis, and augmented oxygen consumption. Treatment of obese diabetic mice with a class I- but not a class II-selective HDAC inhibitor enhanced oxidative metabolism in skeletal muscle and adipose tissue and promoted energy expenditure, thus reducing body weight and glucose and insulin levels. These effects can be ascribed to increased Pgc-1α action in skeletal muscle and enhanced PPARγ/PGC-1α signaling in adipose tissue. In vivo ChIP experiments indicated that inhibition of HDAC3 may account for the beneficial effect of the class I-selective HDAC inhibitor. These results suggest that class I HDAC inhibitors may provide a pharmacologic approach to treating type 2 diabetes.
- Published
- 2013
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159. Inflammatory serum proteome pattern in mice fed a high-fat diet.
- Author
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Gianazza E, Sensi C, Eberini I, Gilardi F, Giudici M, and Crestani M
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- Animals, Blood Proteins chemistry, Blood Proteins genetics, Blood Proteins metabolism, Electrophoresis, Gel, Two-Dimensional, Humans, Inflammation etiology, Inflammation genetics, Lipid Metabolism, Male, Mice, Mice, Inbred C57BL, Proteome chemistry, Proteome genetics, Proteome metabolism, Serum chemistry, Serum metabolism, Diet, High-Fat adverse effects, Inflammation metabolism
- Abstract
To investigate the influence of diet on serum protein pattern, mice were fed for 8 weeks either control chow or a high-fat diet (containing 21 % w/w milk fat and 0.2 % w/w cholesterol); sera were collected and analyzed by 2-DE. The main positive acute-phase reactant proteins, haptoglobin and hemopexin, were significantly up-regulated in animals receiving the high-fat diet. Data on all other proteins also pointed to an inflammatory condition in these animals. The largest change in concentration was observed for carboxylesterase N, a circulating enzyme seldom connected with lipid metabolism in earlier reports. These observations agree with the notion of a link between diet-induced hyperlipidemia and the inflammatory component of its cardiovascular sequels in humans, but the effects in the experimental animals are massive and obviously affect most of the major serum proteins.
- Published
- 2013
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160. [Inconsistency between voltage of the electrocardiogram and the left ventricular wall thickness. diagnostic key in cardiac amyloidosis].
- Author
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Contreras A, Beacon E, Brenna EJ, Parisi GR, Chamale RA, Gilardi F, Bürguesser MV, and Salomone O
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- Amyloidosis complications, Cardiomyopathy, Restrictive etiology, Fatal Outcome, Heart Failure complications, Heart Ventricles physiopathology, Humans, Male, Middle Aged, Myocardium pathology, Ultrasonography, Amyloidosis diagnosis, Cardiomyopathy, Restrictive diagnosis, Electrocardiography methods, Heart Ventricles diagnostic imaging
- Abstract
Restrictive cardiomyopathy is the least common form of cardiomyopathy, and the disease that most often cause it, is the system amyloidosis. We present a 62-year-old with a history of heart failure, which in its assessment highlights the discrepancy between the low voltage ventricular complexes in the electrocardiogram and the severity of left ventricular wall thickness on echocardiography. This discrepancy was the source of suspicion and subsequent confirmation of systemic amyloidosis with cardiac involvement.
- Published
- 2013
161. Site-directed mutagenesis to study the role of specific amino acids in the ligand binding domain of PPARs.
- Author
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Mitro N, Gilardi F, Giudici M, Godio C, Scotti E, and Crestani M
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- DNA Primers genetics, Deoxyribonucleases, Type II Site-Specific metabolism, Escherichia coli cytology, Escherichia coli genetics, HEK293 Cells, Humans, Ligands, Mutation, PPAR gamma genetics, Plasmids genetics, Protein Structure, Tertiary, Transformation, Genetic, Amino Acids metabolism, Mutagenesis, Site-Directed methods, PPAR gamma chemistry, PPAR gamma metabolism
- Abstract
The role of certain amino acids in the interactions of ligands with their cognate nuclear receptors is usually achieved by the resolution of the crystal structure of the receptor complexed with the ligand. As a complementary functional approach, site-directed mutagenesis, a technique broadly used in molecular biology, allows the assessment of the role of a specific amino acid in determining the interaction with a specific ligand. This method makes it possible to evaluate several mutations of a key amino acid for ligand binding and to determine the relationship between protein structure and ligand interaction. Here, we describe an application of this technique to evaluate different point mutations on the transcriptional activity of peroxisome proliferator-activated receptor γ (PPARγ) in the absence or presence of chemically different ligands.
- Published
- 2013
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162. Linking epigenetics to lipid metabolism: focus on histone deacetylases.
- Author
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Ferrari A, Fiorino E, Giudici M, Gilardi F, Galmozzi A, Mitro N, Cermenati G, Godio C, Caruso D, De Fabiani E, and Crestani M
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- Acetylation, Animals, Chromatin genetics, DNA Methylation physiology, Histone Acetyltransferases genetics, Histone Acetyltransferases metabolism, Histone Deacetylases genetics, Histones genetics, Humans, Chromatin metabolism, Epigenesis, Genetic physiology, Histone Deacetylases metabolism, Histones metabolism, Lipid Metabolism physiology, Protein Processing, Post-Translational physiology
- Abstract
A number of recent studies revealed that epigenetic modifications play a central role in the regulation of lipid and of other metabolic pathways such as cholesterol homeostasis, bile acid synthesis, glucose and energy metabolism. Epigenetics refers to aspects of genome functions regulated in a DNA sequence-independent fashion. Chromatin structure is controlled by epigenetic mechanisms through DNA methylation and histone modifications. The main modifications are histone acetylation and deacetylation on specific lysine residues operated by two different classes of enzymes: Histone acetyltransferases (HATs) and histone deacetylases (HDACs), respectively. The interaction between these enzymes and histones can activate or repress gene transcription: Histone acetylation opens and activates chromatin, while deacetylation of histones and DNA methylation compact chromatin making it transcriptionally silent. The new evidences on the importance of HDACs in the regulation of lipid and other metabolic pathways will open new perspectives in the comprehension of the pathophysiology of metabolic disorders.
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- 2012
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163. A multiplicity of factors contributes to selective RNA polymerase III occupancy of a subset of RNA polymerase III genes in mouse liver.
- Author
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Canella D, Bernasconi D, Gilardi F, LeMartelot G, Migliavacca E, Praz V, Cousin P, Delorenzi M, and Hernandez N
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- Animals, Chromatin Immunoprecipitation methods, Humans, Male, Mice, Mice, Inbred C57BL, Models, Genetic, Oligonucleotide Array Sequence Analysis, RNA Polymerase III metabolism, RNA, Transfer genetics, RNA, Transfer metabolism, Sequence Analysis, DNA methods, Gene Expression Profiling, Genomics methods, Liver metabolism, RNA Polymerase III genetics
- Abstract
The genomic loci occupied by RNA polymerase (RNAP) III have been characterized in human culture cells by genome-wide chromatin immunoprecipitations, followed by deep sequencing (ChIP-seq). These studies have shown that only ∼40% of the annotated 622 human tRNA genes and pseudogenes are occupied by RNAP-III, and that these genes are often in open chromatin regions rich in active RNAP-II transcription units. We have used ChIP-seq to characterize RNAP-III-occupied loci in a differentiated tissue, the mouse liver. Our studies define the mouse liver RNAP-III-occupied loci including a conserved mammalian interspersed repeat (MIR) as a potential regulator of an RNAP-III subunit-encoding gene. They reveal that synteny relationships can be established between a number of human and mouse RNAP-III genes, and that the expression levels of these genes are significantly linked. They establish that variations within the A and B promoter boxes, as well as the strength of the terminator sequence, can strongly affect RNAP-III occupancy of tRNA genes. They reveal correlations with various genomic features that explain the observed variation of 81% of tRNA scores. In mouse liver, loci represented in the NCBI37/mm9 genome assembly that are clearly occupied by RNAP-III comprise 50 Rn5s (5S RNA) genes, 14 known non-tRNA RNAP-III genes, nine Rn4.5s (4.5S RNA) genes, and 29 SINEs. Moreover, out of the 433 annotated tRNA genes, half are occupied by RNAP-III. Transfer RNA gene expression levels reflect both an underlying genomic organization conserved in dividing human culture cells and resting mouse liver cells, and the particular promoter and terminator strengths of individual genes.
- Published
- 2012
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164. Synthesis, characterization and biological evaluation of ureidofibrate-like derivatives endowed with peroxisome proliferator-activated receptor activity.
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Porcelli L, Gilardi F, Laghezza A, Piemontese L, Mitro N, Azzariti A, Altieri F, Cervoni L, Fracchiolla G, Giudici M, Guerrini U, Lavecchia A, Montanari R, Di Giovanni C, Paradiso A, Pochetti G, Simone GM, Tortorella P, Crestani M, and Loiodice F
- Subjects
- Adipocytes cytology, Adipocytes drug effects, Adipocytes metabolism, Animals, Antineoplastic Agents chemical synthesis, Antineoplastic Agents chemistry, Antineoplastic Agents pharmacology, Benzoxazoles chemical synthesis, Benzoxazoles pharmacology, Body Weight drug effects, Calorimetry, Cell Differentiation drug effects, Cell Line, Cell Line, Tumor, Cell Proliferation drug effects, Crystallography, X-Ray, Drug Partial Agonism, Drug Screening Assays, Antitumor, Fibroblasts cytology, Fibroblasts drug effects, Fibroblasts metabolism, Gene Expression Profiling, Humans, Insulin Resistance, Intra-Abdominal Fat drug effects, Liver drug effects, Liver metabolism, Mice, Mice, Inbred C57BL, Models, Molecular, PPAR alpha agonists, PPAR alpha genetics, PPAR gamma agonists, PPAR gamma genetics, Propionates chemical synthesis, Propionates pharmacology, Stereoisomerism, Structure-Activity Relationship, Benzoxazoles chemistry, Fibric Acids chemistry, PPAR alpha metabolism, PPAR gamma metabolism, Propionates chemistry, Urea chemistry
- Abstract
A series of ureidofibrate-like derivatives was prepared and assayed for their PPAR functional activity. A calorimetric approach was used to characterize PPARγ-ligand interactions, and docking experiments and X-ray studies were performed to explain the observed potency and efficacy. R-1 and S-1 were selected to evaluate several aspects of their biological activity. In an adipogenic assay, both enantiomers increased the expression of PPARγ target genes and promoted the differentiation of 3T3-L1 fibroblasts to adipocytes. In vivo administration of these compounds to insulin resistant C57Bl/6J mice fed a high fat diet reduced visceral fat content and body weight. Examination of different metabolic parameters showed that R-1 and S-1 are insulin sensitizers. Notably, they also enhanced the expression of hepatic PPARα target genes indicating that their in vivo effects stemmed from an activation of both PPARα and γ. Finally, the capability of R-1 and S-1 to inhibit cellular proliferation in colon cancer cell lines was also evaluated.
- Published
- 2012
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165. Genome-wide RNA polymerase II profiles and RNA accumulation reveal kinetics of transcription and associated epigenetic changes during diurnal cycles.
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Le Martelot G, Canella D, Symul L, Migliavacca E, Gilardi F, Liechti R, Martin O, Harshman K, Delorenzi M, Desvergne B, Herr W, Deplancke B, Schibler U, Rougemont J, Guex N, Hernandez N, and Naef F
- Subjects
- Animals, Chromatin Assembly and Disassembly, Chromatin Immunoprecipitation, DNA Methylation, Half-Life, Histones genetics, Histones metabolism, Kinetics, Liver cytology, Liver metabolism, Male, Mice, Mice, Inbred C57BL, Models, Genetic, Promoter Regions, Genetic, RNA Polymerase II genetics, RNA Processing, Post-Transcriptional, RNA, Messenger analysis, Reverse Transcriptase Polymerase Chain Reaction, Time Factors, Transcription Initiation Site, Transcriptome, Circadian Rhythm, Epigenesis, Genetic, RNA Polymerase II metabolism, RNA, Messenger metabolism, Transcription, Genetic
- Abstract
Interactions of cell-autonomous circadian oscillators with diurnal cycles govern the temporal compartmentalization of cell physiology in mammals. To understand the transcriptional and epigenetic basis of diurnal rhythms in mouse liver genome-wide, we generated temporal DNA occupancy profiles by RNA polymerase II (Pol II) as well as profiles of the histone modifications H3K4me3 and H3K36me3. We used these data to quantify the relationships of phases and amplitudes between different marks. We found that rhythmic Pol II recruitment at promoters rather than rhythmic transition from paused to productive elongation underlies diurnal gene transcription, a conclusion further supported by modeling. Moreover, Pol II occupancy preceded mRNA accumulation by 3 hours, consistent with mRNA half-lives. Both methylation marks showed that the epigenetic landscape is highly dynamic and globally remodeled during the 24-hour cycle. While promoters of transcribed genes had tri-methylated H3K4 even at their trough activity times, tri-methylation levels reached their peak, on average, 1 hour after Pol II. Meanwhile, rhythms in tri-methylation of H3K36 lagged transcription by 3 hours. Finally, modeling profiles of Pol II occupancy and mRNA accumulation identified three classes of genes: one showing rhythmicity both in transcriptional and mRNA accumulation, a second class with rhythmic transcription but flat mRNA levels, and a third with constant transcription but rhythmic mRNAs. The latter class emphasizes widespread temporally gated posttranscriptional regulation in the mouse liver., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2012
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166. [Acute hospital care for the elderly in Italy: comparison between 2001 and 2006].
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Liotta G, Gilardi F, Marazzi MC, Mancinelli S, and Scarcella P
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- Aged, 80 and over, Critical Care economics, Diagnosis-Related Groups economics, Hospital Costs statistics & numerical data, Hospitalization economics, Humans, Italy, Length of Stay economics, Patient Discharge economics, Aged, Critical Care standards, Critical Care statistics & numerical data, Hospitalization statistics & numerical data, Quality of Health Care
- Abstract
The continous health expenditure increase in developed countries is often related with the acute hospital care of the elderly. To monitor the characteristics of elderly acute hospital care included the expenditure trend is crucial in order to identify the appropriateness of this care. The aim of this study is to describe quality and quantity of in-hospital care use of elderly population in Italy in 2006 and to compare the results with the same information gathered for 1996 and 2001. All the 2006 acute hospital admission longer than one day of the patients older than 64 years sourced from the Register of Discharge Form of the Italian Ministry of Health have been analyzed. A list of the 30 more frequent diagnoses has been compiled and compared with the same list compiled for 2001. On the basis of the National Fee for each Disease Related Group an analysis of the hospital expenditure has been carried out. The correlation between DRGs National Fees and frequency of the diagnosis in the discharge form has been based on the 80 diagnosis that has been recorded for more than 10.000 discharge forms in 2006. A relevant increase of acute hospital admission for respiratory, cardiovascular and urinary pathologies among the elderly has been observed. Moreover the number of hospital admissions for major joints and implant of lower limbs is doubled from 1996. The total health expenditure for the elderly acute care longer than one day is increased of 6.3% and a positive correlation between higher DRGs fees and higher frequency of diagnosis has been observed (Pearson correlation value = 0.478; p<0.001 - cubic regression R-square value = 0.301; p<0.001). The hospital acute care use of the elderly patients seems to be more related to emergency care than in the past, while a decrease of DRGs related to chronic diseases and generic diagnosis has been observed. The more frequent cause of in-hospital admission seems to be related also to a higher DRGs fee. As already observed in the past years, a trend towards the use of more expensive DRGs could be detected.
- Published
- 2011
167. Structural insight into peroxisome proliferator-activated receptor gamma binding of two ureidofibrate-like enantiomers by molecular dynamics, cofactor interaction analysis, and site-directed mutagenesis.
- Author
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Pochetti G, Mitro N, Lavecchia A, Gilardi F, Besker N, Scotti E, Aschi M, Re N, Fracchiolla G, Laghezza A, Tortorella P, Montanari R, Novellino E, Mazza F, Crestani M, and Loiodice F
- Subjects
- Benzoxazoles pharmacology, Butyrates pharmacology, Co-Repressor Proteins metabolism, Humans, PPAR gamma genetics, Promoter Regions, Genetic genetics, Protein Binding, Protein Conformation, Rosiglitazone, Stereoisomerism, Structure-Activity Relationship, Thiazolidinediones chemistry, Thiazolidinediones metabolism, Thiazolidinediones pharmacology, Benzoxazoles chemistry, Benzoxazoles metabolism, Butyrates chemistry, Butyrates metabolism, Molecular Dynamics Simulation, Mutagenesis, Site-Directed, PPAR gamma chemistry, PPAR gamma metabolism
- Abstract
Molecular dynamics simulations were performed on two ureidofibrate-like enantiomers to gain insight into their different potency and efficacy against PPARgamma. The partial agonism of the S enantiomer seems to be due to its capability to stabilize different regions of the receptor allowing the interaction with both coactivators and corepressors as shown by fluorescence resonance energy transfer (FRET) assays. The recruitment of the corepressor N-CoR1 by the S enantiomer on two different responsive elements of PPARgamma regulated promoters was confirmed by chromatin immunoprecipitation assays. Cell-based transcription assays show that PPARgamma coactivator 1alpha (PGC-1alpha) and cAMP response element binding protein-binding protein (CBP) enhance the basal and ligand-stimulated receptor activity acting as coactivators of PPARgamma, whereas the receptor interacting protein 140 (RIP140) and the nuclear corepressor 1 (N-CoR1) repress the transcriptional activity of PPARgamma. We also tested the importance of the residue Q286 on the transcriptional activity of the receptor by site-directed mutagenesis and confirmed its key role in the stabilization of helix 12. Molecular modeling studies were performed to provide a molecular explanation for the different behavior of the mutants.
- Published
- 2010
- Full Text
- View/download PDF
168. When food meets man: the contribution of epigenetics to health.
- Author
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De Fabiani E, Mitro N, Gilardi F, Galmozzi A, Caruso D, and Crestani M
- Subjects
- Bile Acids and Salts metabolism, Chromatin metabolism, Chromatin Assembly and Disassembly genetics, Histone Deacetylases metabolism, Humans, Protein Processing, Post-Translational genetics, Energy Metabolism physiology, Epigenesis, Genetic
- Abstract
Post-translational modifications of chromatin contribute to the epigenetic control of gene transcription. The response to food intake and individual nutrients also includes epigenetic events. Bile acids are necessary for lipid digestion and absorption, and more recently have emerged as signaling molecules. Their synthesis is transcriptionally regulated also in relation to the fasted-to-fed cycle, and interestingly, the underlying mechanisms include chromatin remodeling at promoters of key genes involved in their metabolism. Several compounds present in nutrients affect gene transcription through epigenetic mechanisms and recent studies demonstrate that, beyond the well known anti-cancer properties, they beneficially affect energy metabolism.
- Published
- 2010
- Full Text
- View/download PDF
169. Olive oil phenols modulate the expression of metalloproteinase 9 in THP-1 cells by acting on nuclear factor-kappaB signaling.
- Author
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Dell'Agli M, Fagnani R, Galli GV, Maschi O, Gilardi F, Bellosta S, Crestani M, Bosisio E, De Fabiani E, and Caruso D
- Subjects
- Cell Line, Tumor, DNA Primers, Gene Expression Regulation, Enzymologic drug effects, Gene Expression Regulation, Neoplastic drug effects, Humans, Leukemia, Myeloid, NF-kappa B physiology, Olive Oil, Phenols isolation & purification, Promoter Regions, Genetic, Reverse Transcriptase Polymerase Chain Reaction, Signal Transduction drug effects, Transcription, Genetic drug effects, Tumor Necrosis Factor-alpha pharmacology, Matrix Metalloproteinase 9 genetics, NF-kappa B genetics, Phenols pharmacology, Plant Oils chemistry, Signal Transduction physiology
- Abstract
In vivo studies suggest that the phenolic component contributes to the anti-inflammatory and antiatherosclerotic actions of olive oil; however, the effects in circulating cells are not fully characterized. Monocytes play a key role in inflammation-based diseases by expressing several molecules, including metalloproteinases (MMPs). In the present study, we investigated the effects of olive oil phenolic extract and individual compounds on MMP-9 in THP-1 cells, a human monocyte-like cell line. Olive oil extract prevented the stimulation of MMP-9 expression and secretion in tumor necrosis factor alpha-treated THP-1 cells. Oleuropein aglycone, a typical olive oil phenol, was active at concentrations found in the extract, although other compounds probably contribute to the biological activity. We also found that the effect of the extract and individual compounds on MMP-9 is due to impaired nuclear factor-kappaB signaling. Our findings provide further evidence on the mechanisms by which olive oil reduces the inflammatory burden associated with disorders, such as atherosclerosis.
- Published
- 2010
- Full Text
- View/download PDF
170. Sterol-protein interactions in cholesterol and bile acid synthesis.
- Author
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De Fabiani E, Mitro N, Gilardi F, and Crestani M
- Subjects
- Animals, Cytochrome P-450 Enzyme System metabolism, Endoplasmic Reticulum metabolism, Feedback, Physiological, Humans, Intracellular Signaling Peptides and Proteins physiology, Liver X Receptors, Orphan Nuclear Receptors physiology, Receptors, G-Protein-Coupled physiology, Sterols metabolism, Bile Acids and Salts biosynthesis, Cholesterol biosynthesis
- Abstract
Cholesterol and other cholesterol related metabolites, oxysterols, and bile acids, establish specific interactions with enzymes and other proteins involved in cholesterol and bile acid homeostasis, triggering a variety of biological responses. The substrate-enzyme binding represents the best-characterized type of complementary interaction between proteins and small molecules. Key enzymes in the pathway that converts cholesterol to bile acids belong to the cytochrome P450 superfamily. In contrast to the majority of P450 enzymes, those acting on cholesterol and related metabolites exhibit higher stringency with respect to substrate molecules. This stringency, coupled with the specificity of the reactions, dictates the chemical features of intermediate metabolites (oxysterols) and end products (bile acids). Both oxysterols and bile acids have emerged in recent years as new signalling molecules due to their ability to interact and activate nuclear receptors, and consequently to regulate the transcription of genes involved in cholesterol and bile acid homeostasis and metabolism, but also in glucose and fatty acid metabolism. Interestingly, other proteins function as bile acid or sterol receptors. New findings indicate that bile acids also interact with a membrane G protein-coupled receptor, triggering a signalling cascade that ultimately promote energy expenditure. On the other end, cholesterol and side chain oxysterols establish specific interactions with different proteins residing in the endoplasmic reticulum that result in controlled protein degradation and/or trafficking to the Golgi and the nucleus. These regulatory pathways converge and contribute to adapt cholesterol uptake and synthesis to the cellular needs.
- Published
- 2010
- Full Text
- View/download PDF
171. Crystal structure of the peroxisome proliferator-activated receptor gamma (PPARgamma) ligand binding domain complexed with a novel partial agonist: a new region of the hydrophobic pocket could be exploited for drug design.
- Author
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Montanari R, Saccoccia F, Scotti E, Crestani M, Godio C, Gilardi F, Loiodice F, Fracchiolla G, Laghezza A, Tortorella P, Lavecchia A, Novellino E, Mazza F, Aschi M, and Pochetti G
- Subjects
- Animals, Chemistry, Pharmaceutical methods, Crystallography, X-Ray methods, Drug Design, Humans, Hypoglycemic Agents pharmacology, Ligands, Mice, Models, Chemical, Models, Molecular, Molecular Conformation, PPAR alpha chemistry, PPAR gamma agonists, Protein Conformation, Protein Structure, Tertiary, Biphenyl Compounds pharmacology, PPAR alpha metabolism, PPAR gamma metabolism, Phenylpropionates pharmacology
- Abstract
The peroxisome proliferator-activated receptors (PPARs) are ligand-dependent transcription factors regulating glucose and lipid metabolism. The search for new PPAR ligands with reduced adverse effects with respect to the marketed antidiabetic agents thiazolidinediones (TZDs) and the dual-agonists glitazars is highly desired. We report the crystal structure and activity of the two enantiomeric forms of a clofibric acid analogue, respectively complexed with the ligand-binding domain (LBD) of PPARgamma, and provide an explanation on a molecular basis for their different potency and efficacy against PPARgamma. The more potent S-enantiomer is a dual PPARalpha/PPARgamma agonist which presents a partial agonism profile against PPARgamma. Docking of the S-enantiomer in the PPARalpha-LBD has been performed to explain its different subtype pharmacological profile. The hypothesis that partial agonists show differential stabilization of helix 3, when compared to full agonists, is also discussed. Moreover, the structure of the complex with the S-enantiomer reveals a new region of the PPARgamma-LBD never sampled before by other ligands.
- Published
- 2008
- Full Text
- View/download PDF
172. Bile acids and gene regulation: from nuclear receptors to chromatin.
- Author
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Mitro N, Gilardi F, Godio C, Scotti E, De Fabiani E, Caruso D, and Crestani M
- Subjects
- Animals, Cholesterol 7-alpha-Hydroxylase drug effects, Cholesterol 7-alpha-Hydroxylase genetics, Chromatin drug effects, DNA-Binding Proteins drug effects, DNA-Binding Proteins genetics, Humans, Mice, Receptors, Cytoplasmic and Nuclear drug effects, Receptors, Cytoplasmic and Nuclear physiology, Transcription Factors drug effects, Transcription Factors genetics, Transcription, Genetic drug effects, Bile Acids and Salts pharmacology, Chromatin physiology, Gene Expression Regulation drug effects, Receptors, Cytoplasmic and Nuclear genetics
- Abstract
Transcription regulation by bile acids is far more complicated than it appeared at first when several groups began their investigations in the early '90. It has become clear now that bile acids regulate the transcription of genes involved in bile acid synthesis, transport and other metabolic pathways via multiple mechanisms that involve transcription factors, nuclear receptors, coregulators, chromatin and the related modifying enzyme complexes. At a first look this might seem surprising but if one considers the physical-chemical properties of these molecules it should be evident that, due to their detergent properties, bile acids may be harmful if they reach high concentrations in the liver and intestine. Therefore, living organisms have developed biochemical mechanisms that finely tune the concentration of bile acids according to the body needs and in response to environmental challenges. In this review, we will discuss the most recent evidences on the mechanisms through which bile acids regulate gene transcription, including the function of nuclear receptors and emphasizing the emerging role of chromatin and the associated modifying enzymes.
- Published
- 2008
- Full Text
- View/download PDF
173. The pharmacological exploitation of cholesterol 7alpha-hydroxylase, the key enzyme in bile acid synthesis: from binding resins to chromatin remodelling to reduce plasma cholesterol.
- Author
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Gilardi F, Mitro N, Godio C, Scotti E, Caruso D, Crestani M, and De Fabiani E
- Subjects
- Animals, Cholesterol metabolism, Cholesterol 7-alpha-Hydroxylase drug effects, Cholesterol 7-alpha-Hydroxylase genetics, Circadian Rhythm, Diet, Gene Expression Regulation, Enzymologic, Homeostasis, Humans, Receptors, Cytoplasmic and Nuclear physiology, Signal Transduction, Anticholesteremic Agents pharmacology, Bile Acids and Salts metabolism, Cholesterol 7-alpha-Hydroxylase physiology, Chromatin Assembly and Disassembly drug effects, Ion Exchange Resins pharmacology
- Abstract
Mammals dispose of cholesterol mainly through 7alpha-hydroxylated bile acids, and the enzyme catalyzing the 7alpha-hydroxylation, cholesterol 7alpha-hydroxylase (CYP7A1), has a deep impact on cholesterol homeostasis. In this review, we present the study of regulation of CYP7A1 as a good exemplification of the extraordinary contribution of molecular biology to the advancement of our understanding of metabolic pathways that has taken place in the last 2 decades. Since the cloning of the gene from different species, experimental evidence has accumulated, indicating that the enzyme is mainly regulated at the transcriptional level and that bile acids are the most important physiological inhibitors of CYP7A1 transcription. Multiple mechanisms are involved in the control of CYP7A1 transcription and a variety of transcription factors and nuclear receptors participate in sophisticated regulatory networks. A higher order of transcriptional regulation, stemming from the so-called histone code, also applies to CYP7A1, and recent findings clearly indicate that chromatin remodelling events have profound effects on its expression. CYP7A1 also acts as a sensor of signals coming from the gut, thus representing another line of defence against the toxic effects of bile acids and a downstream target of agents acting at the intestinal level. From the pharmacological point of view, bile acid binding resins were the first primitive approach targeting the negative feed-back regulation of CYP7A1 to reduce plasma cholesterol. In recent years, new drugs have been designed based on recent discoveries of the regulatory network, thus confirming the position of CYP7A1 as a focus for innovative pharmacological intervention.
- Published
- 2007
- Full Text
- View/download PDF
174. Bile acids and their signaling pathways: eclectic regulators of diverse cellular functions.
- Author
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Scotti E, Gilardi F, Godio C, Gers E, Krneta J, Mitro N, De Fabiani E, Caruso D, and Crestani M
- Subjects
- Bile Acids and Salts, Glucose metabolism, Humans, Lipid Metabolism, Signal Transduction, DNA-Binding Proteins metabolism, Receptors, Cytoplasmic and Nuclear metabolism, Transcription Factors metabolism
- Abstract
The field of bile acids has witnessed an impulse in the last two decades. This has been the result of cloning the genes encoding enzymes of bile acid synthesis and their transporters. There is no doubt that the identification of Farnesoid X Receptor (FXR, NR1H4) as the bile acid receptor has contributed substantially to attract the interest of scientists in this area. When FXR was cloned by Forman et al. [1], farnesol metabolites were initially considered the physiological ligands. After identifying FXR and other nuclear receptors as bile acid sensors [2-4], it has become clear that bile acids are involved in the regulation of lipid and glucose metabolism and that these molecules are eclectic regulators of diverse cellular functions. In this review, we will summarize the current knowledge of the functions regulated by bile acids and how their physiological receptors mediate the signaling underlying numerous cellular responses.
- Published
- 2007
- Full Text
- View/download PDF
175. Insights in the regulation of cholesterol 7alpha-hydroxylase gene reveal a target for modulating bile acid synthesis.
- Author
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Mitro N, Godio C, De Fabiani E, Scotti E, Galmozzi A, Gilardi F, Caruso D, Vigil Chacon AB, and Crestani M
- Subjects
- Animals, Bile Acids and Salts genetics, Bile Acids and Salts pharmacology, Cell Nucleus enzymology, DNA-Binding Proteins antagonists & inhibitors, DNA-Binding Proteins metabolism, Feedback, Physiological, Histone Acetyltransferases analysis, Histone Acetyltransferases genetics, Histone Acetyltransferases metabolism, Histone Deacetylases analysis, Histone Deacetylases genetics, Humans, Isoxazoles pharmacology, Lipoproteins, LDL metabolism, Male, Mice, Mice, Inbred C57BL, Nuclear Receptor Co-Repressor 2, Promoter Regions, Genetic, RNA, Messenger analysis, RNA, Messenger metabolism, RNA, Small Interfering pharmacology, Receptors, Cytoplasmic and Nuclear antagonists & inhibitors, Repressor Proteins metabolism, Transcription Factors antagonists & inhibitors, Transcription, Genetic genetics, Bile Acids and Salts biosynthesis, Cholesterol 7-alpha-Hydroxylase genetics, Gene Expression Regulation, Histone Deacetylases metabolism
- Abstract
Unlabelled: The transcription of the gene (CYP7A1) encoding cholesterol 7alpha-hydroxylase, a key enzyme in cholesterol homeostasis, is repressed by bile acids via multiple mechanisms involving members of the nuclear receptor superfamily. Here, we describe a regulatory mechanism that can be exploited for modulating bile acid synthesis. By dissecting the mechanisms of CYP7A1 transcription, we found that bile acids stimulate the sequential recruitment of the histone deacetylases (HDACs) 7, 3, and 1, and of the corepressor SMRTalpha (silencing mediator of retinoid and thyroid receptors-alpha) and the nuclear corepressor. Bile acids, but not the farnesoid X receptor-selective agonist GW4064, increase the nuclear concentration of HDAC7, which promotes the assembly of a repressive complex that ultimately represses CYP7A1 transcription. Interestingly, despite its high basal expression level, small heterodimer partner (SHP) is associated with the CYP7A1 promoter only at a later stage of bile acid repression. Gene silencing with small interfering RNA confirms that HDAC7 is the key factor required for the repression of CYP7A1 transcription, whereas knockdown of SHP does not prevent the down-regulation of CYP7A1. Administration of the HDAC inhibitors valproic acid or trichostatin A to genetically hypercholesterolemic mice increases Cyp7a1 messenger RNA and bile acid synthesis and consequently markedly reduces total plasma and low-density lipoprotein cholesterol., Conclusion: By using a combination of molecular, cellular, and animal models, our study highlights the importance of HDACs in the feedback regulation of CYP7A1 transcription and identifies these enzymes as potential targets to modulate bile acid synthesis and for the treatment of hypercholesterolemia.
- Published
- 2007
- Full Text
- View/download PDF
176. Molecular mechanisms underlying mancozeb-induced inhibition of TNF-alpha production.
- Author
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Corsini E, Viviani B, Birindelli S, Gilardi F, Torri A, Codecà I, Lucchi L, Bartesaghi S, Galli CL, Marinovich M, and Colosio C
- Subjects
- Biotransformation drug effects, Blotting, Western, Cell Line, Cell Line, Tumor, Dose-Response Relationship, Drug, Ethylenethiourea toxicity, Genes, Reporter, Humans, L-Lactate Dehydrogenase metabolism, Lipopolysaccharides pharmacology, NF-kappa B metabolism, Reactive Oxygen Species metabolism, Reverse Transcriptase Polymerase Chain Reaction, Transcription Factors genetics, Transcription, Genetic drug effects, Ziram toxicity, Fungicides, Industrial toxicity, Maneb toxicity, Tumor Necrosis Factor-alpha biosynthesis, Zineb toxicity
- Abstract
Mancozeb, a polymeric complex of manganese ethylenebisdithiocarbamate with zinc salt, is widely used in agriculture as fungicide. Literature data indicate that ethylenebisdithiocarbamates (EBDTCs) may have immunomodulatory effects in humans. We have recently found in agricultural workers occupationally exposed to the fungicide mancozeb a statistically significant decrease in lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF) production in leukocytes. TNF is an essential proinflammatory cytokine whose production is normally stimulated during an infection. The purpose of this work was to establish an in vitro model reflecting in vivo data and to characterize the molecular mechanism of action of mancozeb. The human promyelocytic cell line THP-1 was used as in vitro model to study the effects of mancozeb and its main metabolite ethylenthiourea (ETU) on LPS-induced TNF release. Mancozeb, but not ETU, at non-cytotoxic concentrations (1-100 microg/ml), induced a dose- and time-dependent inhibition of LPS-induced TNF release, reflecting in vivo data. The modulatory effect observed was not limited to mancozeb but also other EBDTCs, namely zineb and ziram, showed similar inhibitory effects. Mancozeb must be added before or simultaneously to LPS in order to observe the effect, indicating that it acts on early events triggered by LPS. It is known that nuclear factor-kappaB (NF-kappaB) tightly regulates TNF transcription. We could demonstrate that mancozeb, modulating LPS-induced reactive oxygen species generation, prevented IkappaB degradation and NF-kappaB nuclear translocation, which in turn resulted in decreased TNF production. To further understand the mechanism of the effect of mancozeb on TNF transcription, THP-1 cells were transfected with NF-kappaB promoter-luciferase construct, and the effect of mancozeb on luciferase activity was measured. Cells transfected with promoter constructs containing kappaB site showed decreased LPS-induced luciferase activity relative to control after mancozeb treatment, confirming NF-kappaB binding as an intracellular target of mancozeb. Overall, this study contributes to our understanding of the mechanism underlying mancozeb-induced immunotoxicity.
- Published
- 2006
- Full Text
- View/download PDF
177. Bile acid signaling to the nucleus: finding new connections in the transcriptional regulation of metabolic pathways.
- Author
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De Fabiani E, Mitro N, Godio C, Gilardi F, Caruso D, and Crestani M
- Subjects
- Animals, Fatty Acids metabolism, Fatty Acids physiology, Gene Expression Regulation, Humans, Models, Biological, Peroxisome Proliferator-Activated Receptors genetics, Peroxisome Proliferator-Activated Receptors metabolism, Receptors, Steroid physiology, Sterols metabolism, Bile Acids and Salts physiology, Cell Nucleus physiology, Signal Transduction physiology, Transcription, Genetic physiology
- Abstract
Recent findings indicate that the function of metabolically relevant genes is finely regulated at the level of gene transcription. Disturbances of these regulatory pathways often lead to metabolic unbalance and to the onset of socially relevant diseases, i.e. diabetes, metabolic syndrome, atherosclerosis and cardiovascular diseases. The ability of lipid metabolites, such as fatty acids and oxysterols, to signal to cells and tissues and to affect gene transcription by activating specific nuclear receptors has been known since several years. Bile acids have been known in the past as cholesterol end products, purely acting as detergents. Only recently new biological properties of bile acids as signaling molecules have been disclosed and appreciated. In this review, we will describe how bile acids can regulate their own synthesis and other metabolic pathways (i.e. glucose metabolism) by modulating gene transcription through multiple mechanisms. These findings also open new perspectives towards the exploitation of bile acid metabolism as a pharmacological target.
- Published
- 2004
- Full Text
- View/download PDF
178. Coordinated control of cholesterol catabolism to bile acids and of gluconeogenesis via a novel mechanism of transcription regulation linked to the fasted-to-fed cycle.
- Author
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De Fabiani E, Mitro N, Gilardi F, Caruso D, Galli G, and Crestani M
- Subjects
- 3' Untranslated Regions, Animals, Basic Helix-Loop-Helix Leucine Zipper Transcription Factors, Blotting, Western, Cell Line, Cholesterol 7-alpha-Hydroxylase metabolism, Chromatin metabolism, DNA-Binding Proteins metabolism, Down-Regulation, Genes, Reporter, Genetic Vectors, Glutathione Peroxidase, Hepatocyte Nuclear Factor 4, Humans, Ligands, Male, Mice, Mice, Inbred C57BL, Models, Biological, Phosphoproteins metabolism, Plasmids metabolism, Precipitin Tests, Promoter Regions, Genetic, Protein Structure, Tertiary, Proteins metabolism, RNA Polymerase II metabolism, RNA, Messenger metabolism, Receptors, Cytoplasmic and Nuclear, Reverse Transcriptase Polymerase Chain Reaction, Transcription Factors metabolism, Transfection, Bile Acids and Salts metabolism, Cholesterol metabolism, Cholesterol 7-alpha-Hydroxylase genetics, Gene Expression Regulation, Gluconeogenesis, Transcription, Genetic
- Abstract
Bile acid metabolism plays an essential role in cholesterol homeostasis and is critical for the initiation of atherosclerotic disease. However, despite the recent advances, the molecular mechanisms whereby bile acids regulate gene transcription and cholesterol homeostasis in mammals still need further investigations. Here, we show that bile acids suppress transcription of the gene (CYP7A1) encoding cholesterol 7alpha-hydroxylase, the rate-limiting enzyme in bile acid biosynthesis, also through an unusual mechanism not involving the bile acid nuclear receptor, farnesoid X receptor. By performing cell-based reporter assays, protein/protein interaction, and chromatin immunoprecipitation assays, we demonstrate that bile acids impair the recruitment of peroxisome proliferator-activated receptor-gamma coactivator-1alpha and cAMP response element-binding protein-binding protein by hepatocyte nuclear factor-4alpha, a master regulator of CYP7A1. We also show for the first time that bile acids inhibit transcription of the gene (PEPCK) encoding phosphoenolpyruvate carboxykinase, the rate-limiting enzyme in gluconeogenesis, through the same farnesoid X receptor-independent mechanism. Chromatin immunoprecipitation assay revealed that bile acid-induced dissociation of coactivators from hepatocyte nuclear factor-4alpha decreased the recruitment of RNA polymerase II to the core promoter and downstream in the 3'-untranslated regions of these two genes, reflecting the reduction of gene transcription. Finally, we found that Cyp7a1 expression was stimulated in fasted mice in parallel to Pepck, whereas the same genes were repressed by bile acids. Collectively, these results reveal a novel regulatory mechanism that controls gene transcription in response to extracellular stimuli and argue that the transcription regulation by bile acids of genes central to cholesterol and glucose metabolism should be viewed dynamically in the context of the fasted-to-fed cycle.
- Published
- 2003
- Full Text
- View/download PDF
179. [ANGIOTENSIN].
- Author
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GILARDI FF, LANUCARA P, MARINI U, BERETTA R, and FANTINI F
- Subjects
- Angiotensins
- Published
- 1964
180. [Incidence of tuberculosis among the guests of free overnight lodging-houses of Milan].
- Author
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GILARDI F
- Subjects
- Humans, Incidence, Biometry, Liver Neoplasms, Tuberculosis statistics & numerical data
- Published
- 1958
181. [The water-electrolyte composition of the plasma and of various tissues of dogs adrenalectomized and treated with hydrocortisone and aldosterone].
- Author
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CAVALCA L, GILARDI FF, and MARINI U
- Subjects
- Animals, Dogs, Adrenalectomy, Aldosterone pharmacology, Electrolytes, Hydrocortisone pharmacology, Plasma, Water, Water-Electrolyte Balance
- Published
- 1961
182. [INFLUENCE OF PHOSPHOCREATINE ON CARBOHYDRATE METABOLISM IN NORMAL AND HYPERTHYROID SUBJECTS].
- Author
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LANUCARA P, GILARDI FF, and CAVALCA L
- Subjects
- Humans, Carbohydrate Metabolism, Coenzymes, Hyperthyroidism, Phosphocreatine
- Published
- 1964
183. [Formation & inactivation of hormones of the adrenal medulla in the organism].
- Author
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CAVALCA L, GILARDI FF, and MARINI U
- Subjects
- Adrenal Medulla, Epinephrine, Hormones, Norepinephrine metabolism
- Published
- 1958
184. [Results of pneumoperitoneum in therapy of pulmonary tuberculosis].
- Author
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CORBETTA V, CAFIERO F, GILARDI F, and CORBELLA EG
- Subjects
- Abdomen, Insufflation, Pneumoperitoneum, Pneumoperitoneum, Artificial therapeutic use, Tuberculosis, Pulmonary
- Published
- 1953
185. [Effect of adrenalectomy on the water-electrolyte composition of plasma and of various tissues in the dog].
- Author
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MARINI U, GILARDI FF, BERETTA R, and CAVALCA L
- Subjects
- Animals, Dogs, Adrenalectomy, Electrolytes, Plasma, Water, Water-Electrolyte Balance
- Published
- 1961
186. [Radiological aspects of pulmonary localizations of Besnier-Boeck-Schaumann disease].
- Author
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BAGNI G, GILARDI F, MIRADOLI E, and SCARDIGLI B
- Subjects
- Humans, Lung Diseases diagnosis, Sarcoidosis diagnosis
- Published
- 1957
187. [Carbon monoxide in the blood].
- Author
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PARMEGGIANI L and GILARDI F
- Subjects
- Tobacco Products, Carbon Monoxide blood
- Published
- 1952
188. [Incidence and aspects of tuberculosis industrial and agricultural occupational groups (dispensary zone of Sesto San Giovanni, Casalpusterlengo, Codogno)].
- Author
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BAGNI G, GILARDI F, and SCARDIGLI B
- Subjects
- Humans, Incidence, Agriculture, Industry, Tuberculosis statistics & numerical data
- Published
- 1958
189. [Statistical data on the relation of gastroduodenal ulcer to pulmonary tuberculosis].
- Author
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CORBELLA EG and GILARDI F
- Subjects
- Humans, Peptic Ulcer, Tuberculosis, Tuberculosis, Pulmonary
- Published
- 1952
190. [Pneumoperitoneum in the treatment of pleuropulmonary tuberculosis; 109 cases].
- Author
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CORBETTA V, CAFIERO F, GILARDI F, and CORBELLA G
- Subjects
- Insufflation, Pneumoperitoneum, Pulmonary Surgical Procedures, Tuberculosis, Tuberculosis, Pulmonary surgery
- Published
- 1950
191. [Mechanism of the antihypertensive action of benzothiazine drugs].
- Author
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GILARDI FF, MARINI U, BERETTA R, and CAVALCA L
- Subjects
- Humans, Antihypertensive Agents, Hypertension
- Published
- 1962
192. [Plasmatic, urinary and tissular water-electrolyte changes in dogs with hypertension induced by baroceptive deafferentation, treated with hydrochlorothiazide].
- Author
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CAVALCA L, GILARDI FF, MARINI U, and BERETTA R
- Subjects
- Animals, Chlorothiazide analogs & derivatives, Dogs, Electrolytes, Hydrochlorothiazide, Hypertension, Neurosurgical Procedures, Urinary Tract, Water, Water-Electrolyte Balance
- Published
- 1961
193. [Effects of adrenalectomy on the water-electrolyte composition of the plasma and of various tissues of dogs with hypertension induced by baroceptive deafferentation].
- Author
-
GILARDI FF, MARINI U, NOVI C, and CAVALCA L
- Subjects
- Animals, Dogs, Adrenalectomy, Electrolytes, Hypertension metabolism, Neurosurgical Procedures, Plasma, Water, Water-Electrolyte Balance
- Published
- 1961
194. [Respiratory function in pulmonary emphysema].
- Author
-
MANTERO O, LONGHINI E, and GILARDI FF
- Subjects
- Humans, Emphysema, Pulmonary Emphysema physiology, Respiratory Function Tests
- Published
- 1958
195. [Myopathies associated with thyroid disorders].
- Author
-
Cernibori A and Gilardi FF
- Subjects
- Adult, Aspartate Aminotransferases metabolism, Creatine Kinase metabolism, Electromyography, Female, Fructose-Bisphosphate Aldolase metabolism, Humans, Hyperthyroidism enzymology, L-Lactate Dehydrogenase metabolism, Middle Aged, Muscular Diseases enzymology, Thiamine metabolism, Hyperthyroidism complications, Muscular Diseases etiology
- Published
- 1972
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