Claudia Colussi - Academia.edu (original) (raw)

Papers by Claudia Colussi

Circulation

INTRODUCTION: Stem cells derived from diabetes patients often loose most of their regenerative po... more INTRODUCTION: Stem cells derived from diabetes patients often loose most of their regenerative potential. Aims of this study were: 1) investigate the epigenetic basis of diabetes-dependent alterations in cardiac stromal cells (CStC) obtained from diabetes patients (D-CStC); 2) identify potential pharmacological interventions to restore their function. METHODS AND RESULTS: CStC were isolated from volunteer normoglycaemic (N=12) and type-2 diabetic patients (D-CStC, N=8) and long-term cultured in DMEM, 20% fetal bovine serum at normal glucose concentration (5 mM). In this condition, D-CStC revealed impaired proliferation (3 fold reduction), compared to controls, marked by reduced histone H3 serine 10 phosphorylation (H3S10P), decreased ability to form capillary like-structure and the presence of senescence-associated acidic beta-galactosidase. A global histone code profiling indicated a marked reduction in histone H3 Lysine 9 and 14 acetylation (H3K9Ac; H3K14Ac) and a relative increas...

Current biology : CB, Jan 4, 2002

Mismatch repair (MMR) corrects replication errors. It requires the MSH2, MSH6, MLH1, and PMS2 pro... more Mismatch repair (MMR) corrects replication errors. It requires the MSH2, MSH6, MLH1, and PMS2 proteins which comprise the MutSalpha and MutLalpha heterodimers. Inactivation of MSH2 or MLH1 in human tumors greatly increases spontaneous mutation rates. Oxidation produces many detrimental DNA alterations against which cells deploy multiple protective strategies. The Ogg-1 DNA glycosylase initiates base excision repair (BER) of 8-oxoguanine (8-oxoG) from 8-oxoG:C pairs. The Myh DNA glycosylase removes mismatched adenines incorporated opposite 8-oxoG during replication. Subsequent BER generates 8-oxoG:C pairs, a substrate for excision by Ogg-1. MTH1-an 8-oxodGTPase which eliminates 8-oxodGTP from the dNTP pool-affords additional protection by minimizing 8-oxodGMP incorporation during replication. Here we show that the dNTP pool is, nevertheless, an important source of DNA 8-oxoG and that MMR provides supplementary protection by excising incorporated 8-oxodGMP. Incorporated 8-oxodGMP cont...

PLOS ONE, 2015

Saphenous vein graft disease is a timely problem in coronary artery bypass grafting. Indeed, afte... more Saphenous vein graft disease is a timely problem in coronary artery bypass grafting. Indeed, after exposure of the vein to arterial blood flow, a progressive modification in the wall begins, due to proliferation of smooth muscle cells in the intima. As a consequence, the graft progressively occludes and this leads to recurrent ischemia. In the present study we employed a novel ex vivo culture system to assess the biological effects of arterial-like pressure on the human saphenous vein structure and physiology, and to compare the results to those achieved in the presence of a constant low pressure and flow mimicking the physiologic vein perfusion. While under both conditions we found an activation of Matrix Metallo-Proteases 2/9 and of microRNAs-21/146a/221, a specific effect of the arterial-like pressure was observed. This consisted in a marked geometrical remodeling, in the suppression of Tissue Inhibitor of Metallo-Protease-1, in the enhanced expression of TGF-β 1 and BMP-2 mRNAs and, finally, in the upregulation of microRNAs-138/200b/200c. In addition, the veins exposed to arterial-like pressure showed an increase in the density of the adventitial vasa vasorum and of cells co-expressing NG2, CD44 and SM22α markers in the adventitia. Cells with nuclear expression of Sox-10, a transcription factor characterizing multipotent vascular stem cells, were finally found in adventitial vessels. Our findings suggest, for the first time, a role of arterial-like wall strain in the activation of pro-pathologic pathways resulting in adventitial vessels growth, activation of vasa vasorumcells, and upregulation of specific gene products associated to vascular remodeling and inflammation.

Cardiovascular research, 2010

The effect of histone deacetylase inhibitors on dystrophic heart function is not established. To ... more The effect of histone deacetylase inhibitors on dystrophic heart function is not established. To investigate this aspect, dystrophic mdx mice and wild-type (WT) animals were treated 90 days either with suberoylanilide hydroxamic acid (SAHA, 5 mg/kg/day) or with an equivalent amount of vehicle. The following parameters were evaluated: (i) number of ventricular arrhythmias in resting and stress conditions (restraint test) or after aconitine administration; (ii) cardiac excitability, conduction velocity, and refractoriness; (iii) expression and distribution of connexins (Cxs) and Na(v)1.5 sodium channel. Ventricular arrhythmias were negligible in all resting animals. During restraint, however, an increase in the number of arrhythmias was detected in vehicle-treated mdx mice (mdx-V) when compared with SAHA-treated mdx (mdx-SAHA) mice or normal control (WT-V). Interestingly, aconitine, a sodium channel pharmacologic opener, induced ventricular arrhythmias in 83% of WT-V mice, 11% of mdx-...

Arteriosclerosis, Thrombosis, and Vascular Biology, 2012

PLoS ONE, 2013

In previous work we have documented the nuclear translocation of endothelial NOS (eNOS) and its p... more In previous work we have documented the nuclear translocation of endothelial NOS (eNOS) and its participation in combinatorial complexes with Estrogen Receptor Beta (ERb) and Hypoxia Inducible Factors (HIFs) that determine localized chromatin remodeling in response to estrogen (E2) and hypoxia stimuli, resulting in transcriptional regulation of genes associated with adverse prognosis in prostate cancer (PCa). To explore the role of nuclear eNOS in the acquisition of aggressive phenotype in PCa, we performed ChIP-Sequencing on chromatin-associated eNOS from cells from a primary tumor with poor outcome and from metastatic LNCaP cells. We found that: 1. the eNOS-bound regions (peaks) are widely distributed across the genome encompassing multiple transcription factors binding sites, including Estrogen Response Elements. 2. E2 increased the number of peaks, indicating hormone-dependent eNOS re-localization. 3. Peak distribution was similar with/without E2 with < 55% of them in extragenic DNA regions and an intriguing involvement of the 59 domain of several miRs deregulated in PCa. Numerous potentially novel eNOS-targeted genes have been identified suggesting that eNOS participates in the regulation of large gene sets. The parallel finding of downregulation of a cluster of miRs, including miR-34a, in PCa cells associated with poor outcome led us to unveil a molecular link between eNOS and SIRT1, an epigenetic regulator of aging and tumorigenicity, negatively regulated by miR-34a and in turn activating eNOS. E2 potentiates miR-34a downregulation thus enhancing SIRT1 expression, depicting a novel eNOS/SIRT1 interplay fine-tuned by E2-activated ER signaling, and suggesting that eNOS may play an important role in aggressive PCa.

The FASEB Journal, 2009

The aim of this work was to identify micro-RNAs (miRNAs) involved in the pathological pathways ac... more The aim of this work was to identify micro-RNAs (miRNAs) involved in the pathological pathways activated in skeletal muscle damage and regeneration by both dystrophin absence and acute ischemia. Eleven miRNAs were deregulated both in MDX mice and in Duchenne muscular dystrophy patients (DMD signature). Therapeutic interventions ameliorating the mdx-phenotype rescued DMD-signature alterations. The significance of DMD-signature changes was characterized using a damage/regeneration mouse model of hind-limb ischemia and newborn mice. According to their expression, DMD-signature miRNAs were divided into 3 classes. 1) Regeneration miRNAs, miR-31, miR-34c, miR-206, miR-335, miR-449, and miR-494, which were induced in MDX mice and in DMD patients, but also in newborn mice and in newly formed myofibers during postischemic regeneration. Notably, miR-206, miR-34c, and miR-335 were up-regulated following myoblast differentiation in vitro. 2) Degenerative-miRNAs, miR-1, miR-29c, and miR-135a, that were down-modulated in MDX mice, in DMD patients, in the degenerative phase of the ischemia response, and in newborn mice. Their down-modulation was linked to myofiber loss and fibrosis. 3) Inflammatory miRNAs, miR-222 and miR-223, which were expressed in damaged muscle areas, and their expression correlated with the presence of infiltrating inflammatory cells. These findings show an important role of miRNAs in physiopathological pathways regulating muscle response to damage and regeneration.-Greco, S., De Simone, M., Colussi, C., Zaccagnini, G., Fasanaro, P., Pescatori, M., Cardani, R., Perbellini, R., Isaia, E., Sale, P., Meola, G., Capogrossi, M. C., Gaetano, C., Martelli, F. Common micro-RNA signature in skeletal muscle damage and regeneration induced by Duchenne muscular dystrophy and acute ischemia. FASEB J. 23, 3335-3346 (2009). www.fasebj.org 3335 0892-6638/09/0023-3335 © FASEB

Proceedings of the National Academy of Sciences, 2011

Wanting to explore the epigenetic basis of Duchenne cardiomyopathy, we found that global histone ... more Wanting to explore the epigenetic basis of Duchenne cardiomyopathy, we found that global histone acetylase activity was abnormally elevated and the acetylase P300/CBP-associated factor (PCAF) coimmunoprecipitated with connexin 43 (Cx43), which was N ε -lysine acetylated and lateralized in mdx heart. This observation was paralleled by Cx43 dissociation from N-cadherin and zonula occludens 1, whereas pp60-c-Src association was unaltered. In vivo treatment of mdx with the pan-histone acetylase inhibitor anacardic acid significantly reduced Cx43 N ε -lysine acetylation and restored its association to GAP junctions (GJs) at intercalated discs. Noteworthy, in normal as well as mdx mice, the class IIa histone deacetylases 4 and 5 constitutively colocalized with Cx43 either at GJs or in the lateralized compartments. The class I histone deacetylase 3 was also part of the complex. Treatment of normal controls with the histone deacetylase pan-inhibitor suberoylanilide hydroxamic acid (MC1568) or the class IIa-selective inhibitor 3-{4-[3-(3-fluorophenyl)-3-oxo-1-propen-1-yl]-1-methyl-1H-pyrrol-2-yl}-N-hydroxy-2-propenamide (MC1568) determined Cx43 hyperacetylation, dissociation from GJs, and distribution along the long axis of ventricular cardiomyocytes. Consistently, the histone acetylase activator pentadecylidenemalonate 1b (SPV106) hyperacetylated cardiac proteins, including Cx43, which assumed a lateralized position that partly reproduced the dystrophic phenotype. In the presence of suberoylanilide hydroxamic acid, cell to cell permeability was significantly diminished, which is in agreement with a Cx43 close conformation in the consequence of hyperacetylation. Additional experiments, performed with Cx43 acetylation mutants, revealed, for the acetylated form of the molecule, a significant reduction in plasma membrane localization and a tendency to nuclear accumulation. These results suggest that Cx43 N ε -lysine acetylation may have physiopathological consequences for cell to cell coupling and cardiac function. muscular dystrophy | protein acetylation

PLoS ONE, 2008

The regulation of gene transcription requires posttranslational modifications of histones that, i... more The regulation of gene transcription requires posttranslational modifications of histones that, in concert with chromatin remodeling factors, shape the structure of chromatin. It is currently under intense investigation how this structure is modulated, in particular in the context of proliferation and differentiation. Compelling evidence suggests that the transcription factor NF-Y acts as a master regulator of cell cycle progression, activating the transcription of many cell cycle regulatory genes. However, the underlying molecular mechanisms are not yet completely understood. Here we show that NF-Y exerts its effect on transcription through the modulation of the histone ''code''. NF-Y colocalizes with nascent RNA, while RNA polymerase II is I phosphorylated on serine 2 of the YSPTSPS repeats within its carboxyterminal domain and histones are carrying modifications that represent activation signals of gene expression (H3K9ac and PAN-H4ac). Comparing postmitotic muscle tissue from normal mice and proliferating muscles from mdx mice, we demonstrate by chromatin immunoprecipitation (ChIP) that NF-Y DNA binding activity correlates with the accumulation of acetylated histones H3 and H4 on promoters of key cell cycle regulatory genes, and with their active transcription. Accordingly, p300 is recruited onto the chromatin of NF-Y target genes in a NF-Y-dependent manner, as demonstrated by Re-ChIP. Conversely, the loss of NF-Y binding correlates with a decrease of acetylated histones, the recruitment of HDAC1, and a repressed heterochromatic state with enrichment of histones carrying modifications known to mediate silencing of gene expression (H3K9me3, H3K27me2 and H4K20me3). As a consequence, NF-Y target genes are downregulated in this context. In conclusion, our data indicate a role of NF-Y in modulating the structure and transcriptional competence of chromatin in vivo and support a model in which NF-Y-dependent histone ''code'' changes contribute to the proper discrimination between proliferating and postmitotic cells in vivo and in vitro.

Pharmacology & Therapeutics, 2009

The discovery of nitric oxide (NO) revealed its ambiguous nature, which is related to its pleiotr... more The discovery of nitric oxide (NO) revealed its ambiguous nature, which is related to its pleiotropic activities that control the homeostasis of every organism from bacteria to mammals in several physiological and pathological situations. The wide range of action of NO basically depends on two features: 1) the variety of chemical reactions depending on NO, and 2) the differential cellular responses elicited by distinct NO concentrations. Despite the increasing body of knowledge regarding its chemistry, biology and NOdependent signaling pathways, little information is available on the nuclear actions of NO in terms of gene expression regulation. Indeed, studies of a putative role for this diatomic compound in regulating chromatin remodeling are still in their infancy. Only recently has the role of NO in epigenetics emerged, and some of its putative epigenetic properties are still only hypothetical. In the present review, we discuss the current evidence for NO-related mechanisms of epigenetic gene expression regulation. We link some of the well known NO chemical reactions and metabolic processes (e.g., S-nitrosylation of thiols, tyrosine nitration, cGMP production) to chromatin modification and address the most recent, striking hypothesis about NO and the control of chromosomes structure.

Pharmacological Research, 2010

Histone deacetylases (HDACs) are enzymes with a pleiotropic range of intracellular localizations ... more Histone deacetylases (HDACs) are enzymes with a pleiotropic range of intracellular localizations and actions. They are principally involved in the withdrawal of acetyl-groups from a large number of nuclear and cytoplasmic proteins including nuclear core histones as well as cytoskeletal proteins and metabolically relevant enzymes. Initial findings indicated that HDAC inhibitors (DIs) could be successfully applied in a variety of cancer treatment protocols as a consequence of their anti-proliferative and pro-apoptotic properties. Recent observations, however, enlightened the important therapeutic effects of DIs in experimental animal models for arthritis, neurodegenerative and neuromuscular disorders, heart ischemia, cardiac hypertrophy, heart failure and arrhythmias. A small number of clinical trials are now open or planned for the near future to verify the therapeutic properties of DIs in non-cancer-related diseases. This review summarizes some of the most important observations and concepts aroused by the most recent experimental application of DIs to neuromuscular and cardiac diseases.

Neuroscience, 2013

Abbreviations: Ach, acetylcholine; GAPDH, glyceraldehyde dehydrogenase; Go, nucleotide-binding pr... more Abbreviations: Ach, acetylcholine; GAPDH, glyceraldehyde dehydrogenase; Go, nucleotide-binding protein G; GS, glutamine synthetase; 5-HT, 5-hydroxytryptamine; HSC70, heat shock cognate 70; PWTs, paw withdrawal thresholds; sFRP-4, secreted frizzled-related protein 4 precursor; S-MtCK, sarcomeric mitochondrial creatine kinase; SNI, spinal nerve injury

Nature Medicine, 2006

Pharmacological interventions that increase myofiber size counter the functional decline of dystr... more Pharmacological interventions that increase myofiber size counter the functional decline of dystrophic muscles 1,2 . We show that deacetylase inhibitors increase the size of myofibers in dystrophin-deficient (MDX) and a-sarcoglycan (a-SG)deficient mice by inducing the expression of the myostatin antagonist follistatin 3 in satellite cells. Deacetylase inhibitor treatment conferred on dystrophic muscles resistance to contraction-coupled degeneration and alleviated both morphological and functional consequences of the primary genetic defect. These results provide a rationale for using deacetylase inhibitors in the pharmacological therapy of muscular dystrophies.

Molecular Endocrinology, 2011

We recently identified in prostate tumors (PCa) a transcriptional prognostic signature comprising... more We recently identified in prostate tumors (PCa) a transcriptional prognostic signature comprising a significant number of genes differentially regulated in patients with worse clinical outcome. Induction of up-regulated genes was due to chromatin remodeling by a combinatorial complex between estrogen receptor (ER)-β and endothelial nitric oxide synthase (eNOS). Here we show that this complex can also repress transcription of prognostic genes that are down-regulated in PCa, such as the glutathione transferase gene GSTP1. Silencing of GSTP1 is a common early event in prostate carcinogenesis, frequently caused by promoter hypermethylation. We validated loss of glutathione transferase (GST) P1-1 expression in vivo, in tissue microarrays from a retrospective cohort of patients, and correlated it with decreased disease-specific survival. Furthermore, we show that in PCa cultured cells ERβ/eNOS causes GSTP1 repression by being recruited at estrogen responsive elements in the gene promoter with consequential remodeling of local chromatin. Treatment with ERβ antagonist or its natural ligand 5α-androstane-3β,17β-diol, eNOS inhibitors or ERβ small interference RNA abrogated the binding and reversed GSTP1 silencing, demonstrating the direct involvement of the complex. In vitro, GSTP1 silencing by ERβ/eNOS was specific for cells from patients with worse clinical outcome where it appeared the sole mechanism regulating GSTP1 expression because no promoter hypermethylation was present. However, in vivo chromatin immunoprecipitation assays on fresh PCa tissues demonstrated that silencing by ERβ/eNOS can coexist with promoter hypermethylation. Our findings reveal that the ERβ/eNOS complex can exert transcriptional repression and suggest that this may represent an epigenetic event favoring inactivation of the GSTP1 locus by methylation. Moreover, abrogation of ERβ/eNOS function by 3β-adiol emphasizes the significance of circulating or locally produced sex steroid hormones or their metabolites in PCa biology with relevant clinical/therapeutic implications.

Journal of the American College of Cardiology, 2002

last acute event. Such condition is associated with an enhanced responsiveness to proinflammatory... more last acute event. Such condition is associated with an enhanced responsiveness to proinflammatory stimuli. Thus, NF-K B activation might represent a mechanism by which CRP amplifies and perpetuates the inflammatory component of acute coronary syndromes.

International Journal of Cancer, 2000

Together with tolerance to killing induced by methylating agents, loss of mismatch repair (MMR) h... more Together with tolerance to killing induced by methylating agents, loss of mismatch repair (MMR) has previously been found to be associated with hypersensitivity to the DNA cross-linking agent 1-(2-chloroethyl)-3-cyclohexyl-nitrosourea (CCNU) in several human tumor cell lines (Aquilina et al., 1998). Here, we have investigated whether MMR might act as an efficient repair pathway and provide protection against the clastogenicity induced by CCNU and whether the hypersensitivity of MMR-defective cells is extended to other crosslinking agents. An increase in cell killing and in the frequency of micronuclei was observed after CCNU exposure in 2 hPMS2-defective clones (clones 6 and 7) compared with the parental HeLa cells. Introduction of a wild-type copy of chromosome 7 in clone 7 led to re-expression of the hPMS2 protein and brought survival and chromosomal damage upon CCNU exposure to parental levels. Our data indicate that MMR protects against the clastogenic damage induced by this drug. The hPMS2-defective HeLa cells were also hypersensitive to killing by mitomycin C. Mitomycin C sensitivity was confirmed in an hMLH1-defective clone derived from Raji cells and in msh2-defective mouse embryo fibroblasts derived from knock-out mice. hPMS2-defective and parental HeLa cells were transplanted into nude mice, and the animals were treated with mitomycin C. While parental cell growth rate was unaffected, the growth of MMR-defective tumor was significantly reduced. Our results indicate that the in vitro hypersensitivity to mitomycin C conferred by loss of MMR is paralleled in vivo and may have implications for the chemotherapy of MMR-defective tumors. Int.

Faseb Journal, 2000

H2O2 treatment on U937 cells leads to the block of glycolytic flux and the inactivation of glycer... more H2O2 treatment on U937 cells leads to the block of glycolytic flux and the inactivation of glyceraldehyde-3-phosphate-dehydrogenase by a posttranslational modification (possibly ADP-ribosy- lation). Glycolysis spontaneously reactivates after 2 h of recovery from oxidative stress; thereafter cells begin to undergo apoptosis. The specific ADP-ribo- sylation inhibitor 3-aminobenzamide inhibits the stress-induced inactivation of glyceraldehyde-3-phos- phate-dehydrogenase and the block of glycolysis; concomitantly,

Current Biology, 2002

mouse embryo fibroblasts (MEFs) contained approximately 2-fold more oxidized guanines than DNA fr... more mouse embryo fibroblasts (MEFs) contained approximately 2-fold more oxidized guanines than DNA from msh2 ϩ/ϩ MEFs. The average values were 0.68 and 0.34 8-oxoG per 10 6 guanines for msh2 Ϫ/Ϫ and wild-type cells, respectively (p Ͻ 0.0001, Student's t test for paired sam-

Circulation Research, 2008

Nitric oxide (NO) modulates important endothelial cell (EC) functions and gene expression by a mo... more Nitric oxide (NO) modulates important endothelial cell (EC) functions and gene expression by a molecular mechanism which is still poorly characterized. Here we show that in human umbilical vein ECs (HUVECs) NO inhibited serum-induced histone acetylation and enhanced histone deacetylase (HDAC) activity. By immunofluorescence and Western blot analyses it was found that NO induced class II HDAC4 and 5 nuclear shuttling and that class II HDACs selective inhibitor MC1568 rescued serum-dependent histone acetylation above control level in NO-treated HUVECs. In contrast, class I HDACs inhibitor MS27-275 had no effect, indicating a specific role for class II HDACs in NO-dependent histone deacetylation. In addition, it was found that NO ability to induce HDAC4 and HDAC5 nuclear shuttling involved the activation of the protein phosphatase 2A (PP2A). In fact, HDAC4 nuclear translocation was impaired in ECs expressing small-t antigen and exposed to NO. Finally, in cells engineered to express a HDAC4-Flag fusion protein, NO induced the formation of a macromolecular complex including HDAC4, HDAC3, HDAC5, and an active PP2A. The present results show that NO-dependent PP2A activation plays a key role in class II HDACs nuclear translocation. (Circ Res. 2008;102:51-58.)