ABSTRACT
Extra virgin olive oil (EVOO) consumption has been associated with reduced cardiovascular risk but molecular mechanisms underlying its beneficial effects are not fully understood. Here we aimed to identify genes and miRNAs expression changes mediated by acute high- and low-polyphenols EVOO intake. Pre- and post-challenge gene and miRNAs expression analysis was performed on the peripheral blood mononuclear cells (PBMCs) of 12 healthy subjects and 12 patients with metabolic syndrome (MS) by using microarray and RT-qPCR. In healthy subjects, acute intake of EVOO rich in polyphenols was able to ameliorate glycaemia and insulin sensitivity, and to modulate the transcription of genes and miRNAs involved in metabolism, inflammation and cancer, switching PBMCs to a less deleterious inflammatory phenotype; weaker effects were observed in patients with MS as well as in healthy subjects following low-polyphenol EVOO challenge. Concluding, our study shows that acute high-polyphenols EVOO intake is able to modify the transcriptome of PBMCs through the modulation of different pathways associated with the pathophysiology of cardio-metabolic disease and cancer. These beneficial effects are maximized in healthy subjects, and by the use of EVOO cultivars rich in polyphenols. Nutrigenomic changes induced by EVOO thus legitimate the well-known beneficial effects of EVOO in promoting human health and, potentially, preventing the onset of cardiovascular disease and cancer.
Subject(s)
Feeding Behavior , Gene Expression Profiling , Healthy Volunteers , Leukocytes, Mononuclear/metabolism , Metabolic Syndrome/genetics , MicroRNAs/genetics , Olive Oil/administration & dosage , Adult , Female , Gene Expression Regulation/drug effects , Humans , Leukocytes, Mononuclear/drug effects , Male , MicroRNAs/metabolism , Polyphenols/pharmacology , Real-Time Polymerase Chain Reaction , Reproducibility of ResultsABSTRACT
The mucosa of the small intestine is renewed completely every 3-5 d throughout the entire lifetime by small populations of adult stem cells that are believed to reside in the bottom of the crypts and to migrate and differentiate into all the different populations of intestinal cells. When the cells reach the apex of the villi and are fully differentiated, they undergo cell death and are shed into the lumen. Reactive oxygen species (ROS) production is proportional to the electron transfer activity of the mitochondrial respiration chain. ROS homeostasis is maintained to control cell death and is finely tuned by an inducible antioxidant program. Here we show that peroxisome proliferator-activated receptor-γ coactivator-1ß (PGC-1ß) is highly expressed in the intestinal epithelium and possesses dual activity, stimulating mitochondrial biogenesis and oxygen consumption while inducing antioxidant enzymes. To study the role of PGC-1ß gain and loss of function in the gut, we generated both intestinal-specific PGC-1ß transgenic and PGC-1ß knockout mice. Mice overexpressing PGC-1ß present a peculiar intestinal morphology with very long villi resulting from increased enterocyte lifespan and also demonstrate greater tumor susceptibility, with increased tumor number and size when exposed to carcinogens. PGC-1ß knockout mice are protected from carcinogenesis. We show that PGC-1ß triggers mitochondrial respiration while protecting enterocytes from ROS-driven macromolecule damage and consequent apoptosis in both normal and dysplastic mucosa. Therefore, PGC-1ß in the gut acts as an adaptive self-point regulator, capable of providing a balance between enhanced mitochondrial activity and protection from increased ROS production.
Subject(s)
Colonic Neoplasms/pathology , Enterocytes/cytology , Intestinal Mucosa/pathology , Intestine, Small/pathology , Transcription Factors/metabolism , Animals , Antioxidants/metabolism , Apoptosis , Carcinogenesis , Electron Transport , Gene Expression Profiling , Gene Expression Regulation , Homeostasis , Immunohistochemistry , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mitochondria/metabolism , Oxygen/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Reactive Oxygen Species/metabolism , Transcription Factors/geneticsABSTRACT
UNLABELLED: Farnesoid X receptor (FXR) is the master regulator of bile acid (BA) homeostasis because it controls BA synthesis, influx, efflux, and detoxification in the gut/liver axis. Deregulation of BA homeostasis has been linked to hepatocellular carcinoma (HCC), and spontaneous hepatocarcinogenesis has been observed in FXR-null mice. This dreaded liver neoplasm has been associated with both FXR gene deletion and BA-mediated metabolic abnormalities after inactivation of FXR transcriptional activity. In the present study, we addressed the hypothesis that intestinal selective FXR reactivation would be sufficient to restore the fibroblast growth factor 15 (FGF15)/cholesterol-7alpha-hydroxylase (Cyp7a1) enterohepatic axis and eventually provide protection against HCC. To this end, we generated FXR-null mice with re-expression of constitutively active FXR in enterocytes (FXR(-/-)iVP16FXR) and corresponding control mice (FXR(-/-)iVP16). In FXR-null mice, intestinal selective FXR reactivation normalized BA enterohepatic circulation along with up-regulation of intestinal FXR transcriptome and reduction of hepatic BA synthesis. At 16 months of age, intestinal FXR reactivation protected FXR-null mice from spontaneous HCC development that occurred in otherwise FXR-null mice. Activation of intestinal FXR conferred hepatoprotection by restoring hepatic homeostasis, limiting cellular proliferation through reduced cyclinD1 expression, decreasing hepatic inflammation and fibrosis (decreased signal transducer and activator of transcription 3 activation and curtailed collagen deposition). CONCLUSION: Intestinal FXR is sufficient to restore BA homeostasis through the FGF15 axis and prevent progression of liver damage to HCC even in the absence of hepatic FXR. Intestinal-selective FXR modulators could stand as potential therapeutic intervention to prevent this devastating hepatic malignancy, even if carrying a somatic FXR mutation.
Subject(s)
Bile Acids and Salts/metabolism , Carcinoma, Hepatocellular/etiology , Intestinal Mucosa/metabolism , Liver Neoplasms/etiology , Receptors, Cytoplasmic and Nuclear/metabolism , Aging/metabolism , Animals , Basic Helix-Loop-Helix Transcription Factors/metabolism , Down-Regulation , Female , Fibroblast Growth Factors/metabolism , Genes, cdc , Homeostasis , Male , Mice, Inbred C57BL , Mice, Transgenic , Receptors, Aryl Hydrocarbon/metabolismABSTRACT
BACKGROUND: Nuclear receptors are a class of 48 ligand-activated transcription factors identified as key players of metabolic and developmental processes. Most of these receptors are potential targets for pharmacological strategies in the Metabolic Syndrome. In the present study, we analyzed changes in the mRNA expression of nuclear receptors in the peripheral blood mononuclear cells of patients with Metabolic Syndrome, in order to identify novel biomarkers of disease and candidate targets for putative therapeutical approaches. METHODS AND RESULTS: We enrolled thirty healthy controls (14 M:16 F) and thirty naïve patients (16 M: 14 F; >3 criteria for Metabolic Syndrome upon Adult Treatment Panel III) without organ damage. Using quantitative real-time PCR, we assessed the expression patterns of nuclear receptors in peripheral blood mononuclear cells. 33/48 nuclear receptors were expressed in peripheral blood mononuclear cells. In patients with Metabolic Syndrome, we found a significant down-regulation of the entire PPAR, NR4A and RAR families, together with a repression of RXRα, VDR, and Rev-Erbα. Furthermore, we performed a novel statistical analysis with classification trees, which allowed us to depict a predictive core of nuclear receptor expression patterns characterizing subjects with Metabolic Syndrome. Random Forest Analysis identified NOR1 and PPARδ, which were both reduced in peripheral blood mononuclear cells and specifically in CD14(+) cells (mostly monocytes), as classifiers of Metabolic Syndrome, with high specificity and sensitivity. CONCLUSIONS: Our results point to the use of PPAR and NR4A mRNA levels in the overall peripheral blood mononuclear cells as biomarkers of Metabolic Syndrome and bona fide putative targets of pharmacological therapy.
Subject(s)
Biomarkers/metabolism , Leukocytes, Mononuclear/metabolism , Metabolic Syndrome/diagnosis , Receptors, Cytoplasmic and Nuclear/genetics , Transcription Factors/genetics , Adult , Blotting, Western , Case-Control Studies , Cohort Studies , Down-Regulation , Female , Flow Cytometry , Humans , Male , Metabolic Syndrome/genetics , Metabolic Syndrome/metabolism , Middle Aged , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Receptors, Cytoplasmic and Nuclear/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/metabolismABSTRACT
BACKGROUND & AIMS: Studies of the transcriptional networks that regulate nuclear receptor-mediated proliferation of quiescent hepatocytes could lead to new information about liver growth and hepatoprotective strategies. METHODS: We used quantitative real-time PCR to analyze expression of neuron-derived orphan receptor 1 (Nor-1) and its target genes during liver regeneration after hepatectomy in mice, and in hepatocellular carcinoma (HCC) samples from patients. We used adenoviral vectors to express Nor-1 in normal liver (Ad/CMV/V5-Nor-1), or reduce its level with small hairpin RNAs (Ad/BLOCK-iT/Nor-1(small hairpin RNA)) after partial hepatectomy. RESULTS: Levels of Nor-1 messenger RNA and protein, and transcription of Nor-1 target genes (Ccnd1 and Vcam-1), increased during the late priming and proliferative phases of liver regeneration after partial hepatectomy. Levels of NOR-1 messenger RNA and transcription of its target gene CCND1 and of the NOR-1 subfamily member NUR-77 also increased in human HCC samples compared with paired HCC-free tissue. Ad-Nor-1(small hairpin RNA) reduced the hepatocyte proliferation after hepatectomy. Overexpression of Nor-1 in normal livers of mice induced proliferation of quiescent hepatocytes independently of interleukin-6 and tumor necrosis factor-α signaling. In gene expression profile analysis, Nor-1 altered expression of genes involved in the cell cycle, proliferation, and tumorigenesis. CONCLUSIONS: In mice, the orphan nuclear receptor Nor-1 activates proliferation of quiescent hepatocytes and is required for hepatocyte proliferation after partial hepatectomy. Nor-1 and its gene targets are also up-regulated in human HCC samples. Nor-1 activates a transcriptional program that induces hepatocyte proliferation independently of inflammatory signaling pathways.
Subject(s)
Carcinoma, Hepatocellular/metabolism , Cell Proliferation , DNA-Binding Proteins/physiology , Hepatocytes/cytology , Liver Neoplasms/metabolism , Liver Regeneration/physiology , Membrane Transport Proteins/metabolism , Nerve Tissue Proteins/physiology , Receptors, Steroid/physiology , Receptors, Thyroid Hormone/physiology , Animals , Carcinoma, Hepatocellular/genetics , Cyclin D1/genetics , Cyclin D1/metabolism , DNA-Binding Proteins/genetics , Hepatectomy , Humans , Liver Neoplasms/genetics , Liver Regeneration/genetics , Male , Membrane Transport Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Nerve Tissue Proteins/genetics , Nuclear Receptor Subfamily 4, Group A, Member 1/genetics , Nuclear Receptor Subfamily 4, Group A, Member 1/metabolism , RNA, Messenger/analysis , Receptors, Steroid/genetics , Receptors, Thyroid Hormone/genetics , Up-Regulation , Vascular Cell Adhesion Molecule-1/genetics , Vascular Cell Adhesion Molecule-1/metabolismABSTRACT
BACKGROUND & AIMS: Liver X receptors (LXRs) are transcriptional regulators of cholesterol metabolism, controlling cholesterol flow into cells, catabolism, and efflux. Cholesterol controls cell proliferation; disruptions in cholesterol metabolism have been associated with the development of colon cancer. We investigated whether expression of activated LXR protects against intestinal tumorigenesis in mice. METHODS: We analyzed the development of colon cancer in mice that express a constitutive active form of LXRα only in the intestinal epithelium, under the control of villin promoter (iVP16LXRα). These mice were crossed with adenomatous polyposis coli (Apc)(min/+) mice, or given azoxymethane followed by dextran sodium sulfate, to assess intestinal tumor formation. We also assessed proliferation and apoptosis of a human colorectal cancer cell line (HT29) transfected with an adenoviral vector that expressed Ad VP16hLXRα, compared with cells expressing AdVP16 (control), and their ability to form xenograft tumors in mice. HT29 cells also were incubated with the LXR ligand GW3965. RESULTS: In human colorectal cancer cells, ligand-induced activation of LXR or transfection with Ad VP16hLXRα blocked the G1 phase, increased caspase-dependent apoptosis, and slowed growth of xenograft tumors in mice. iVP16LXRα mice formed fewer, smaller tumors than VP16 (control) mice after administration of azoxymethane and dextran sodium sulfate. APC(min/+)/iVP16LXRα mice also developed fewer, smaller intestinal tumors than APC(min/+)/iVP16 mice. Gene expression analysis indicated that activation of LXRα affected lipid metabolic networks and increased cholesterol efflux in the intestine. CONCLUSIONS: Expression of activated LXRα blocks proliferation of human colorectal cancer cells and slows the growth of xenograft tumors in mice. It also reduces intestinal tumor formation after administration of chemical carcinogens, and in Apc(min/+) mice. LXR agonists therefore might be developed as therapeutic treatments for colorectal cancer.
Subject(s)
Adenocarcinoma/metabolism , Adenoma/physiopathology , Cell Transformation, Neoplastic , Colorectal Neoplasms/metabolism , Intestinal Neoplasms/metabolism , Orphan Nuclear Receptors/physiology , Adenocarcinoma/pathology , Animals , Cell Proliferation , Colorectal Neoplasms/pathology , Disease Models, Animal , Genes, APC , HT29 Cells , Humans , Intestinal Neoplasms/pathology , Liver X Receptors , Mice , Mice, Transgenic , Orphan Nuclear Receptors/metabolism , Signal Transduction , Transplantation, HeterologousABSTRACT
Head and neck paragangliomas, rare neoplasms of the paraganglia composed of nests of neurosecretory and glial cells embedded in vascular stroma, provide a remarkable example of organoid tumor architecture. To identify genes and pathways commonly deregulated in head and neck paraganglioma, we integrated high-density genome-wide copy number variation (CNV) analysis with microRNA and immunomorphological studies. Gene-centric CNV analysis of 24 cases identified a list of 104 genes most significantly targeted by tumor-associated alterations. The "NOTCH signaling pathway" was the most significantly enriched term in the list (P = 0.002 after Bonferroni or Benjamini correction). Expression of the relevant NOTCH pathway proteins in sustentacular (glial), chief (neuroendocrine) and endothelial cells was confirmed by immunohistochemistry in 47 head and neck paraganglioma cases. There were no relationships between level and pattern of NOTCH1/JAG2 protein expression and germline mutation status in the SDH genes, implicated in paraganglioma predisposition, or the presence/absence of immunostaining for SDHB, a surrogate marker of SDH mutations. Interestingly, NOTCH upregulation was observed also in cases with no evidence of CNVs at NOTCH signaling genes, suggesting altered epigenetic modulation of this pathway. To address this issue we performed microarray-based microRNA expression analyses. Notably 5 microRNAs (miR-200a,b,c and miR-34b,c), including those most downregulated in the tumors, correlated to NOTCH signaling and directly targeted NOTCH1 in in vitro experiments using SH-SY5Y neuroblastoma cells. Furthermore, lentiviral transduction of miR-200s and miR-34s in patient-derived primary tympano-jugular paraganglioma cell cultures was associated with NOTCH1 downregulation and increased levels of markers of cell toxicity and cell death. Taken together, our results provide an integrated view of common molecular alterations associated with head and neck paraganglioma and reveal an essential role of NOTCH pathway deregulation in this tumor type.
Subject(s)
Epigenesis, Genetic/physiology , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/pathology , Paraganglioma/genetics , Paraganglioma/pathology , Receptors, Notch/genetics , Receptors, Notch/physiology , Signal Transduction/genetics , Signal Transduction/physiology , Blotting, Western , Caspases/metabolism , Cell Death/genetics , Cell Line, Tumor , DNA Mutational Analysis , Fluorescent Antibody Technique , Humans , Immunohistochemistry , Lentivirus/genetics , Microarray Analysis , Microscopy, Immunoelectron , Peripheral Nerves/metabolism , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Succinate Dehydrogenase/genetics , TransfectionABSTRACT
Mutations in the parkin gene are expected to play an essential role in autosomal recessive Parkinson's disease. Recent studies have established an impact of parkin mutations on mitochondrial function and autophagy. In primary skin fibroblasts from two patients affected by an early onset Parkinson's disease, we identified a hitherto unreported compound heterozygous mutation del exon2-3/del exon3 in the parkin gene, leading to the complete loss of the full-length protein. In both patients, but not in their heterozygous parental control, we observed severe ultrastructural abnormalities, mainly in mitochondria. This was associated with impaired energy metabolism, deregulated reactive oxygen species (ROS) production, resulting in lipid oxidation, and peroxisomal alteration. In view of the involvement of parkin in the mitochondrial quality control system, we have investigated upstream events in the organelles' biogenesis. The expression of the peroxisome proliferator-activated receptor gamma-coactivator 1-alpha (PGC-1α), a strong stimulator of mitochondrial biogenesis, was remarkably upregulated in both patients. However, the function of PGC-1α was blocked, as revealed by the lack of its downstream target gene induction. In conclusion, our data confirm the role of parkin in mitochondrial homeostasis and suggest a potential involvement of the PGC-1α pathway in the pathogenesis of Parkinson's disease. This article is part of a Special Issue entitled: Translating nuclear receptors from health to disease.
Subject(s)
Heat-Shock Proteins/physiology , Mitochondria/physiology , Parkinson Disease/physiopathology , Transcription Factors/physiology , Ubiquitin-Protein Ligases/physiology , Adult , Base Sequence , DNA Primers , Energy Metabolism , Female , Fibroblasts/ultrastructure , Humans , Male , Mutation , Oxidative Stress , Parkinson Disease/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
BACKGROUND & AIMS: The WNT-adenomatous polyposis coli system controls cell fate in the intestinal epithelium, where compartment-specific genes tightly regulate proliferation, migration, and differentiation. Nuclear receptors are transcription factors functioning as sensors of hormones and nutrients that are known to contribute to colon cancer progression. Here we mapped the messenger RNA (mRNA) abundance and the epithelial localization of the entire nuclear receptor family in mouse and human intestine. METHODS: We used complementary high-resolution in situ hybridization and systematic real-time quantitative polymerase chain reaction in samples of normal distal ileum and proximal colon mucosa and tumors obtained from mouse and human adenomatous polyposis coli-initiated tumor models (ie, Apc(Min/+) mice and familial adenomatous polyposis patients) and in cellular models of human colon cancer. RESULTS: We first defined for each receptor an expression pattern based on its transcript localization in the distal ileum and the proximal colon. Then, we compared the mRNA levels between normal intestinal epithelium and neoplastic intestinal tissue. After analyzing the correspondence between mouse and human tumor samples plus genetically modified human colon cancer cells, we used complementary graphic and statistical approaches to present a comprehensive overview with several classification trees for the nuclear hormone receptor intestinal transcriptome. CONCLUSIONS: We defined the intestinal nuclear hormone receptor map, which indicates that the localization pattern of a receptor in normal intestine predicts the modulation of its expression in tumors. Our results are useful to select those nuclear receptors that could be used eventually as early diagnostic markers or targeted for clinical intervention in intestinal polyposis and cancer.
Subject(s)
Adenoma/metabolism , Colon/metabolism , Colonic Neoplasms/metabolism , Epithelial Cells/metabolism , Ileum/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Adenoma/pathology , Adenomatous Polyposis Coli/metabolism , Adenomatous Polyposis Coli/pathology , Adolescent , Adult , Animals , Colon/pathology , Colonic Neoplasms/pathology , Disease Models, Animal , Epithelial Cells/pathology , Female , Gene Expression Profiling , Humans , Ileum/pathology , Male , Mice , Mice, Inbred C57BL , RNA, Messenger/metabolism , Receptors, Cytoplasmic and Nuclear/genetics , Young AdultABSTRACT
BACKGROUND: Epicardial adipose tissue (EAT) is an atypical fat depot surrounding the heart with a putative role in the development of atherosclerosis. METHODS AND RESULTS: We profiled genes and miRNAs in perivascular EAT and subcutaneous adipose tissue (SAT) of metabolically healthy patients without coronary artery disease (CAD) vs. metabolic patients with CAD. Compared with SAT, a specific tuning of miRNAs and genes points to EAT as a tissue characterized by a metabolically active and pro-inflammatory profile. Then, we depicted both miRNA and gene signatures of EAT in CAD, featuring a down-regulation of genes involved in lipid metabolism, mitochondrial function, nuclear receptor transcriptional activity, and an up-regulation of those involved in antigen presentation, chemokine signalling, and inflammation. Finally, we identified miR-103-3p as candidate modulator of CCL13 in EAT, and a potential biomarker role for the chemokine CCL13 in CAD. CONCLUSION: EAT in CAD is characterized by changes in the regulation of metabolism and inflammation with miR-103-3p/CCL13 pair as novel putative actors in EAT function and CAD.
Subject(s)
Adipose Tissue/metabolism , Atherosclerosis/genetics , Gene Expression Regulation/genetics , Genetic Predisposition to Disease/genetics , Lipid Metabolism/genetics , MicroRNAs/genetics , Adult , Aged , Aged, 80 and over , Chemokines/metabolism , Genome, Human , Genome-Wide Association Study , Humans , Inflammation/genetics , Male , Middle AgedABSTRACT
BACKGROUND: The renin-angiotensin system is involved in adipocyte growth and differentiation and possibly in adipose tissue metabolism. OBJECTIVE: To investigate the association of polymorphism in the angiotensin-converting enzyme (ACE) I/D gene, angiotensinogen M235T gene, and angiotensin II type 1 receptor A1166C gene with body mass index, body fat pattern, and obesity-associated hypertension. DESIGN: Cross-sectional longitudinal study. SETTING: The Olivetti factories in Marcianise and Pozzuoli, suburbs of Naples, Italy. PARTICIPANTS: 959 adult men, 25 to 75 years of age. MEASUREMENTS: Renin-angiotensin system polymorphism, anthropometric indexes, blood pressure, and serum glucose and insulin levels. RESULTS: No association was detected between angiotensinogen or angiotensin II type 1 receptor gene polymorphism and anthropometric indexes or blood pressure. For ACE I/D polymorphism, significant age-genotype interaction was detected on cross-sectional observation; the relation of body mass index, waist circumference, and diastolic blood pressure to age was significantly greater in persons with the DD genotype than in those with the ID or II genotype. Overweight and abdominal adiposity were more common in men with the DD genotype, particularly among older participants (51.1% vs. 36.5% and 33.1% vs. 22.0%, respectively). Odds ratios were 1.82 (95% CI, 1.16 to 2.87) for overweight and 1.76 (CI, 1.06 to 2.90) for abdominal adiposity. Among 314 untreated men first examined 20 years earlier, those with the DD genotype had greater age-adjusted weight gain (1.45 kg [CI, 0.12 to 2.78 kg]) and change in diastolic blood pressure (2.83 mm Hg [CI, 0.39 to 5.28 mm Hg]). The relative risk for overweight was 2.34 (CI, 1.32 to 4.15) among participants with the DD genotype versus those with the ID or II genotype. CONCLUSIONS: The ACE I/D polymorphism was a significant predictor of overweight and abdominal adiposity in men. DD homozygosity was associated with larger increases in body weight and blood pressure in aging persons, as well as with higher incidence of overweight.
Subject(s)
Abdomen/pathology , Adipose Tissue/pathology , Body Weight/genetics , Obesity/genetics , Obesity/pathology , Renin-Angiotensin System/genetics , Adult , Aged , Angiotensinogen/genetics , Anthropometry , Cross-Sectional Studies , Humans , Hypertension/complications , Hypertension/genetics , Longitudinal Studies , Male , Middle Aged , Obesity/complications , Peptidyl-Dipeptidase A/genetics , Polymorphism, Genetic , Receptor, Angiotensin, Type 1 , Receptors, Angiotensin/geneticsABSTRACT
BACKGROUND & AIMS: Liver regeneration (LR) is a valuable model for studying mechanisms modulating hepatocyte proliferation. Nuclear receptors (NRs) are key players in the control of cellular functions, being ideal modulators of hepatic proliferation and carcinogenesis. METHODS & RESULTS: We used a previously validated RT-qPCR platform to profile modifications in the expression of all 49 members of the NR superfamily in mouse liver during LR. Twenty-nine NR transcripts were significantly modified in their expression during LR, including fatty acid (peroxisome proliferator-activated receptors, PPARs) and oxysterol (liver X receptors, Lxrs) sensors, circadian masters RevErbα and RevErbß, glucocorticoid receptor (Gr) and constitutive androxane receptor (Car). In order to detect the NRs that better characterize proliferative status vs. proliferating liver, we used the novel Random Forest (RF) analysis to selected a trio of down-regulated NRs (thyroid receptor alpha, Trα; farsenoid X receptor beta, Fxrß; Pparδ) as best discriminators of the proliferating status. To validate our approach, we further studied PPARδ role in modulating hepatic proliferation. We first confirmed the suppression of PPARδ both in LR and human hepatocellular carcinoma at protein level, and then demonstrated that PPARδ agonist GW501516 reduces the proliferative potential of hepatoma cells. CONCLUSIONS: Our data suggest that NR transcriptome is modulated in proliferating liver and is a source of biomarkers and bona fide pharmacological targets for the management of liver disease affecting hepatocyte proliferation.
Subject(s)
Carcinoma, Hepatocellular/genetics , Hepatocytes/metabolism , Liver Neoplasms/genetics , Liver Regeneration/genetics , Receptors, Cytoplasmic and Nuclear/genetics , Animals , Carcinoma, Hepatocellular/metabolism , Cell Line , Cell Proliferation , Cluster Analysis , Gene Expression Profiling , Gene Expression Regulation , Humans , Liver/metabolism , Liver Neoplasms/metabolism , Male , Mice , Receptors, Cytoplasmic and Nuclear/metabolism , TranscriptomeABSTRACT
OBJECTIVE: While many studies have shown an association between the gene coding for adiponectin (ADIPOQ) and adiponectin levels, much more controversy surrounds its association with metabolic traits such as insulin resistance, obesity and type 2 diabetes. Furthermore, very few studies have looked into the relations between ADIPOQ variants and risk of cardiovascular disease. The present study assessed the influence of four common ADIPOQ Single Nucleotide Polymorphisms (SNPs), rs17300539 (-11391GâA), rs266729 (-11377CâG), rs2241766 (+45TâG) and rs1501299 (+276GâT) on the risk of myocardial infarction and type 2 diabetes. METHODS: and RESULTS: A large genetic association case-control study was conducted in 2008 Italians, including patients with myocardial infarction, type 2 diabetes, or both, and a reference group of healthy controls. Homozygotes TT for the rs1501299 (+276) had half the risk of either myocardial infarction alone or in association with type 2 diabetes when compared to the carriers of the G allele (OR = 0.58, p =0.01, and OR = 0.55, p =0.006 respectively). SNPs rs17300539 (-11391), rs266729 (-11377) and rs2241766 (+45) showed no significant association with any of the three case groups. CONCLUSIONS: These results suggest that homozygotes TT for the adiponectin polymorphism rs1501299 (+276) are protected from the risk of myocardial infarction.
Subject(s)
Diabetes Mellitus, Type 2/genetics , Myocardial Infarction/genetics , Polymorphism, Single Nucleotide , Adiponectin/genetics , Aged , Analysis of Variance , Case-Control Studies , Chi-Square Distribution , Diabetes Mellitus, Type 2/epidemiology , Female , Gene Frequency , Genetic Association Studies , Genetic Predisposition to Disease , Homozygote , Humans , Italy/epidemiology , Logistic Models , Male , Middle Aged , Myocardial Infarction/epidemiology , Odds Ratio , Risk Assessment , Risk FactorsABSTRACT
AIMS: Controversy exists with regard to the influence of APOE polymorphisms on coronary heart disease development and on the efficacy of statin treatment. we investigated the relationship between apoe, mortality and the response to treatment in Mediterranean myocardial infarction (mi) survivors. METHODS AND RESULTS: We analysed 3304 Italian patients with MI randomized to pravastatin or no treatment in the GISSI-Prevenzione study, with a mean follow-up time of 23.0 +/- 6.7 months (median 24.3 months). Mortality curves were calculated using Kaplan-Meier method, and differences in survival were tested using the log-rank test. There were 109 deaths during follow-up. Patients treated with pravastatin showed a significant decrease in mortality compared with non-treated patients (HR 0.67, 95% confidence interval 0.45-0.97, P = 0.038). Among the 3304 patients, 554 (16.8%) were epsilon4 carriers and 2750 (83.2%) were non-epsilon4 carriers. No significant difference in terms of mortality was observed between the epsilon4 and the non-epsilon4 carriers (3.61% vs. 3.24%, P = 0.67). However, although in non-epsilon4 carriers no significant difference in mortality was observed between patients treated with pravastatin and non-treated (2.81% vs. 3.67%, P = 0.21), among the epsilon4 carriers a significant reduction in mortality was observed in patients treated compared with non-treated (1.85% vs. 5.28%, P = 0.023). CONCLUSION: We found that epsilon4 allele is a determinant of pravastatin response in terms of survival. Though in the entire population investigated,we found a beneficial effect of pravastatin in terms of survival, only the epsilon4 carriers seemed to have gained a significant benefit from this treatment. We suggest that the effect of statins is of particular interest in this fraction of the population. Genetic markers can help in identifying patients that benefit more from statin treatment.
Subject(s)
Apolipoproteins E/genetics , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Myocardial Infarction/drug therapy , Polymorphism, Genetic , Pravastatin/therapeutic use , Female , Follow-Up Studies , Genotype , Heterozygote , Humans , Male , Middle Aged , Myocardial Infarction/genetics , Myocardial Infarction/mortality , Treatment OutcomeABSTRACT
BACKGROUND AND OBJECTIVES: The G20210A polymorphism in the prothrombin gene is a common cause of inherited thrombophilia. Scarce information is available about the circumstances of the heralding thrombotic manifestation at different ages. The aim of this study was to determine the risk of spontaneous or secondary venous thromboembolism (VTE) among younger and older carriers of the G20210A prothrombin polymorphism. DESIGN AND METHODS: We performed a case-control study, investigating 650 patients with a first objectively documented deep venous thrombosis of the legs or pulmonary embolism and 703 individuals with no history of vascular disease. In all of them we carried out laboratory screening for antithrombin III, protein C and protein S deficiencies, and for the presence of the factor V Leiden and the G20210A prothrombin polymorphisms. RESULTS: After adjustment for other inherited causes of thrombophilia (deficiency of antithrombin III, protein C or S, factor V Leiden) the overall risk for VTE associated with the prothrombin polymorphism was 3.4 times higher than in the controls (95% CI, 2.0 to 5.8). Stratification according to the age and to the circumstances of the first event revealed an increased risk of spontaneous VTE only among the patients older than 45 years in comparison with age-matched controls (odds ratio 4.4, 95% CI 1.8 to 10.6); among the younger individuals the risk was increased for secondary VTE (odds ratio 4.8, 95% CI, 2.3 to 9.8) but not for spontaneous VTE. INTERPRETATION AND CONCLUSIONS: The clinical penetrance of the thrombotic tendency associated with the G20210A prothrombin polymorphism is more expressed in the presence of a circumstantial risk factor (oral contraceptives, pregnancy, surgery, trauma) and in the presence of older age, which acts as an additional circumstantial risk factor. Accordingly, such situations should not discourage from carrying out laboratory screening.
Subject(s)
Polymorphism, Single Nucleotide , Prothrombin/genetics , Thromboembolism/genetics , Venous Thrombosis/genetics , Adult , Age Factors , Aged , Aged, 80 and over , Case-Control Studies , Female , Heterozygote , Humans , Italy/epidemiology , Male , Middle AgedABSTRACT
BACKGROUND AND OBJECTIVE: The 4G/5G plasminogen activator inhibitor-1 (PAI-1) promoter polymorphism has been associated with basal PAI-1 levels, with ischemic heart disease, and with adverse prognosis in critically ill patients. We hypothesized it might also influence the acute-phase levels of PAI-1 following coronary bypass surgery. METHODS: In 111 consecutive patients undergoing elective coronary bypass surgery, 4G/5G genotyping and serial plasma PAI-1 activity and antigen levels were prospectively measured before surgery, daily up to 72 h, and at discharge. The inflammatory reaction was additionally assessed by white cell count, fibrinogen, interleukin-6, and C-reactive protein levels. RESULTS: PAI-1 activity and antigen concentrations increased approximately two-fold after surgery, peaking at 48 hours. Carriers of the 4G-allele, compared with 5G/5G homozygotes, showed approximately 20% higher PAI-1 activity and antigen both preoperatively ( P = 0.007 and P = 0.035) and after surgery. White cell count, fibrinogen, interleukin-6, and C-reactive protein values did not differ significantly according to genotypic groups. In multivariate analysis, the 4G/5G genotype was the only significant modulator of postoperative PAI-1 activity (P = 0.003) and the main significant modulator of postoperative PAI-1 antigen (P = 0.013). No significant interaction was found between the effects of time and genotype on postoperative PAI-1. This indicates that the association between 4G/5G and acute-phase PAI-1 levels is secondary to the genotype-related difference of baseline PAI-1. CONCLUSIONS: Postoperative PAI-1 concentrations of patients undergoing elective coronary bypass surgery are higher in carriers of the 4G-allele than in 5G/5G homozygotes as a result of higher baseline values. Knowledge of 4G/5G status may be useful to predict acute-phase PAI-1 concentrations.