αV-Integrin-Dependent Inhibition of Glioblastoma Cell Migration, Invasion and Vasculogenic Mimicry by the uPAcyclin Decapeptide.

Among the deadliest human cancers is glioblastoma (GBM) for which new treatment approaches are urgently needed. Here, the effects of the cyclic decapeptide, uPAcyclin, are investigated using the U87-MG, U251-MG, and U138-MG human GBM and C6 rat cell models. All GBM cells express the αV-integrin subunit, the target of uPAcyclin, and bind specifically to nanomolar concentrations of the decapeptide. Although peptide exposure affects neither viability nor cell proliferation rate, nanomolar concentrations of uPAcyclin markedly inhibit the directional migration and matrix invasion of all GBM cells, in a concentration- and αV-dependent manner. Moreover, wound healing rate closure of U87-MG and C6 rat glioma cells is reduced by 50% and time-lapse videomicroscopy studies show that the formation of vascular-like structures by U87-MG in three-dimensional matrix cultures is markedly inhibited by uPAcyclin. A strong reduction in the branching point numbers of the U87-MG, C6, and U251-MG cell lines undergoing vasculogenic mimicry, in the presence of nanomolar peptide concentrations, was observed. Lysates from matrix-recovered uPAcyclin-exposed cells exhibit a reduced expression of VE-cadherin, a prominent factor in the acquisition of vascular-like structures. In conclusion, these results indicate that uPAcyclin is a promising candidate to counteract the formation of new vessels in novel targeted anti-GBM therapies.

Brugada syndrome and job fitness: report of three cases.

Brugada syndrome (BrS) is an inherited arrhythmogenic disorder predisposing patients to a high risk of sudden cardiac death. Specific guidelines on the health surveillance of BrS workers are lacking. We report here three cases requiring assessment of specific job capacity, investigated with an interdisciplinary protocol including 24-h Holter electrocardiography with modified precordial leads, pharmacological test with ajmaline, molecular genetic analysis, electrophysiological study with ventricular stimulation, risk stratification, and occupational medicine evaluation: (1) a female 42-yr-old company manager with positive ajmaline test and CACNA1C gene mutation (judged fit for the job with limitations regarding work-related stress); (2) a male 44-yr-old welder with positive ajmaline test, SCN5A gene mutation, and associated OSAS (obstructive sleep apnea syndrome), who was advised to refrain from night shifts and driving company vehicles; (3) a male 45-yr-old electrical technician with inducible ventricular tachyarrhythmia, who was implanted with a biventricular cardioverter defibrillator, and therefore recommended to avoid exposure to electromagnetic fields and working at heights. We conclude that the collaboration between the cardiologist and the occupational physician allows defining the functional capabilities and the arrhythmogenic risk of BrS workers, to optimize job fitness assessment.

Understanding the Lost: Reconstruction of the Garden Design of Villa Peretti Montalto (Rome, Italy) for Urban Valorization.

Urbanization and urban regeneration can significantly impact cultural heritage, but a greater knowledge of the past natural and historical features is needed to value the past and understand the present. The lost Villa Peretti Montalto in Rome, once located in the area that corresponds to the current front side of Termini station, deserves great attention due to its cultural value. This work aimed to provide a floristic and functional reconstruction of the gardens of the villa during the XVI and XVII Centuries. From several bibliographic and iconographic sources, a critical analysis and interpretation of plant names was conducted. A list of 87 species and their location in the different garden sectors, during different periods with their specific uses, is provided. The arboreal design was made by classical species in the Roman context, like Cupressus sempervirens, Pinus pinea, Quercus ilex, and Ulmus glabra. In addition, ancient lost varieties of fruit trees (mainly Pyrus communis and Ficus carica) and several species of conservation interest were found. The knowledge of the ancient flora in historical gardens could be a key tool in urban greenery planning and touristic and cultural valorization.

Angiogenesis and Multiple Sclerosis Pathogenesis: A Glance at New Pharmaceutical Approaches.

Multiple sclerosis is a chronic disease of the central nervous system characterized by demyelination and destruction of axons. The most common form of the disease is the relapsing-remitting multiple sclerosis in which episodic attacks with typical neurological symptoms are followed by episodes of partial or complete recovery. One of the underestimated factors that contribute to the pathogenesis of multiple sclerosis is excessive angiogenesis. Here, we review the role of angiogenesis in the onset and in the development of the disease, the molecular mechanisms underlying angiogenesis, the current therapeutic approaches, and the potential therapeutic strategies with a look at natural compounds as multi-target drugs with both neuroprotective and anti-angiogenic properties.

Ruta graveolens water extract (RGWE) ameliorates ischemic damage and improves neurological deficits in a rat model of transient focal brain ischemia.

INTRODUCTION AND AIMS: The limited therapeutic options for ischemic stroke treatment render necessary the identification of new strategies. In recent years, it has been shown that natural compounds may represent a valid therapeutic opportunity. Therefore, the present study aimed to evaluate the protective effect of Ruta graveolens water extract (RGWE) in an in vivo experimental model of brain ischemia. METHODS: RGWE effects on ischemic damage and neurological function were evaluated in adult rats subjected to transient occlusion of the Middle Cerebral Artery (tMCAO), receiving two intraperitoneal injections of RGWE, 100 and 300 min after the induction of ischemia. In addition, astroglial and microglial activation was measured as GFAP and IBA-1 expression by immunofluorescence and confocal microscopy analysis. RESULTS: Treatment with RGWE containing 10 mg/kg of Rutin, the major component, ameliorates the ischemic damage and improves neurological performances. Interestingly, the pro-inflammatory states of astrocytes and microglia, respectively detected by using C3 and iNOS markers, were significantly reduced in ipsilateral cortical and striatal areas in ischemic RGWE-treated rats. CONCLUSIONS: RGWE shows a neuroprotective effect on brain infarct volume extent in a transient focal cerebral ischemia model and this effect was paralleled by the prevention of pro-inflammatory astroglial and microglial activation. Collectively, our findings support the idea that natural compounds may represent potential therapeutic opportunities against ischemic stroke.

Eligibility of outpatients with chronic heart failure for sodium-glucose co-transporter-2 inhibitors.

AIMS: Sodium-glucose co-transporter-2 inhibitors (SGLT2i) have been shown to have a relevant role in the prevention of hospitalizations for heart failure and improvement in the life expectancy of patients with diabetes and outpatients with chronic heart failure (CHF) with reduced left ventricular ejection fraction, independently from the presence of type 2 diabetes mellitus (T2DM). The aim of our study was to evaluate in a real-world population the number of outpatients with CHF who meet the enrolment criteria of the main randomized controlled trials (RCT) published in the last 5 years and consequently identify the percentage of patients who could potential benefit from SGLT2i therapy. METHODS AND RESULTS: We retrospectively evaluated all consecutive outpatients referred for CHF. The diagnosis of T2DM was according to the latest European Society of Cardiology Guidelines. Clinical characteristics considered for the enrolment in the RCTs were recorded. We enrolled 515 patients, 384 (75%) of whom had a left ventricular ejection fraction (LVEF) ≤ 40%, 82 (16%) had pre-diabetes, and 187 (36%) had diabetes. Most of the patients with LVEF ≤ 40% met the criteria for the DAPA-HF trial (65%), and this percentage was even higher if the serum level of N-terminal pro-brain natriuretic peptide was not considered. A high percentage of patients with diabetes and LVEF > 40% met the criteria for the DECLARE (39%), CANVAS (47%), and EMPA-REG (30%) trials. Patients meeting the enrolment criteria of RCTs evaluating SGLT2i were also characterized by a high risk of heart failure events during follow-up. CONCLUSIONS: In spite of a low number of patients actually treated with SGLT2i, we observed that a high prevalence of patients with CHF met the clinical characteristics of RCTs that have demonstrated a beneficial effect of SGLT2i.

Generation of High-Yield, Functional Oligodendrocytes from a c-myc Immortalized Neural Cell Line, Endowed with Staminal Properties.

Neural stem cells represent a powerful tool to study molecules involved in pathophysiology of Nervous System and to discover new drugs. Although they can be cultured and expanded in vitro as a primary culture, their use is hampered by their heterogeneity and by the cost and time needed for their preparation. Here we report that mes-c-myc A1 cells (A1), a neural cell line, is endowed with staminal properties. Undifferentiated/proliferating and differentiated/non-proliferating A1 cells are able to generate neurospheres (Ns) in which gene expression parallels the original differentiation status. In fact, Ns derived from undifferentiated A1 cells express higher levels of Nestin, Kruppel-like factor 4 (Klf4) and glial fibrillary protein (GFAP), markers of stemness, while those obtained from differentiated A1 cells show higher levels of the neuronal marker beta III tubulin. Interestingly, Ns differentiation, by Epidermal Growth Factors (EGF) and Fibroblast Growth Factor 2 (bFGF) withdrawal, generates oligodendrocytes at high-yield as shown by the expression of markers, Galactosylceramidase (Gal-C) Neuron-Glial antigen 2 (NG2), Receptor-Interacting Protein (RIP) and Myelin Basic Protein (MBP). Finally, upon co-culture, Ns-A1-derived oligodendrocytes cause a redistribution of contactin-associated protein (Caspr/paranodin) protein on neuronal cells, as primary oligodendrocytes cultures, suggesting that they are able to form compact myelin. Thus, Ns-A1-derived oligodendrocytes may represent a time-saving and low-cost tool to study the pathophysiology of oligodendrocytes and to test new drugs.

Baseline and incident hypochloremia in chronic heart failure outpatients: Clinical correlates and prognostic role.

BACKGROUND: Electrolyte serum disorders are associated with poor outcome in chronic heart failure. The aim of this study sought to identify the main driver of incident hypochloremia in chronic HF (CHF) outpatients and to determine the prognostic value of baseline and incident hypochloremia. METHODS: Consecutive CHF outpatients were enrolled and clinical, laboratoristic and echocardiographic evaluations were performed at baseline and repeated yearly in a subgroup of patients. Baseline and incident hypochloremia were evaluated. During an up to 5-year follow-up, all-cause mortality was the primary end-point for outcome. RESULTS: Among 506 patients enrolled, 120 patients died during follow-up. At baseline, hypochloremia was present in 10% of patients and it was associated with mortality at univariate (HR: 3.25; 95%CI: 2.04-5.18; p<0.001) and at multivariate analysis (HR 2.14; 95%CI: 1.23-3.63; p: 0.005) after correction for well-established CHF prognostic markers. Among patients with repeated evaluations and without baseline hypochloremia, in 13% of these, incident hypochloremia occurred during follow-up and furosemide equivalent daily dose was its first determinant (HR for 1 mg/die: 1.008; 95%CI: 1.004-1.013; p<0.001) at forward stepwise logistic regression analysis. Finally, incident hypochloremia was associated with mortality at univariate (HR: 4.69; 95%CI: 2.69-8.19; p<0.001) as well as at multivariate analysis (HR: 2.97; 95%CI: 1.48-5.94; p: 0.002). CONCLUSIONS: In CHF outpatients baseline and incident hypochloremia are independently associated with all-cause mortality, thus highlighting the prognostic role of serum chloride levels which are generally unconsidered. Future studies should evaluate if the strict monitoring and correction of hypochloremia could exert a beneficial effect on prognosis.

ZBTB2 protein is a new partner of the Nucleosome Remodeling and Deacetylase (NuRD) complex.

ZBTB2 is a protein belonging to the BTB/POZ zinc-finger family whose members typically contain a BTB/POZ domain at the N-terminus and several zinc-finger domains at the C-terminus. Studies have been carried out to disclose the role of ZBTB2 in cell proliferation, in human cancers and in regulating DNA methylation. Moreover, ZBTB2 has been also described as an ARF, p53 and p21 gene repressor as well as an activator of genes modulating pluripotency. In this scenario, ZBTB2 seems to play many functions likely associated with other proteins. Here we report a picture of the ZBTB2 protein partners in U87MG cell line, identified by high-resolution mass spectrometry (MS) that highlights the interplay between ZBTB2 and chromatin remodeling multiprotein complexes. In particular, our analysis reveals the presence, as ZBTB2 candidate interactors, of SMARCA5 and BAZ1B components of the chromatin remodeling complex WICH and PBRM1, a subunit of the SWI/SNF complex. Intriguingly, we identified all the subunits of the NuRD complex among the ZBTB2 interactors. By co-immunoprecipitation experiments and ChIP-seq analysis we definitely identify ZBTB2 as a new partner of the NuRD complex.

A Heart-Breast Cancer-on-a-Chip Platform for Disease Modeling and Monitoring of Cardiotoxicity Induced by Cancer Chemotherapy.

Cardiotoxicity is one of the most serious side effects of cancer chemotherapy. Current approaches to monitoring of chemotherapy-induced cardiotoxicity (CIC) as well as model systems that develop in vivo or in vitro CIC platforms fail to notice early signs of CIC. Moreover, breast cancer (BC) patients with preexisting cardiac dysfunctions may lead to different incident levels of CIC. Here, a model is presented for investigating CIC where not only induced pluripotent stem cell (iPSC)-derived cardiac tissues are interacted with BC tissues on a dual-organ platform, but electrochemical immuno-aptasensors can also monitor cell-secreted multiple biomarkers. Fibrotic stages of iPSC-derived cardiac tissues are promoted with a supplement of transforming growth factor-ß 1 to assess the differential functionality in healthy and fibrotic cardiac tissues after treatment with doxorubicin (DOX). The production trend of biomarkers evaluated by using the immuno-aptasensors well-matches the outcomes from conventional enzyme-linked immunosorbent assay, demonstrating the accuracy of the authors' sensing platform with much higher sensitivity and lower detection limits for early monitoring of CIC and BC progression. Furthermore, the versatility of this platform is demonstrated by applying a nanoparticle-based DOX-delivery system. The proposed platform would potentially help allow early detection and prediction of CIC in individual patients in the future.

Neurotrophic Factor BDNF, Physiological Functions and Therapeutic Potential in Depression, Neurodegeneration and Brain Cancer.

Brain-derived neurotrophic factor (BDNF) is one of the most distributed and extensively studied neurotrophins in the mammalian brain. BDNF signals through the tropomycin receptor kinase B (TrkB) and the low affinity p75 neurotrophin receptor (p75NTR). BDNF plays an important role in proper growth, development, and plasticity of glutamatergic and GABAergic synapses and through modulation of neuronal differentiation, it influences serotonergic and dopaminergic neurotransmission. BDNF acts as paracrine and autocrine factor, on both pre-synaptic and post-synaptic target sites. It is crucial in the transformation of synaptic activity into long-term synaptic memories. BDNF is considered an instructive mediator of functional and structural plasticity in the central nervous system (CNS), influencing dendritic spines and, at least in the hippocampus, the adult neurogenesis. Changes in the rate of adult neurogenesis and in spine density can influence several forms of learning and memory and can contribute to depression-like behaviors. The possible roles of BDNF in neuronal plasticity highlighted in this review focus on the effect of antidepressant therapies on BDNF-mediated plasticity. Moreover, we will review data that illustrate the role of BDNF as a potent protective factor that is able to confer protection against neurodegeneration, in particular in Alzheimer's disease. Finally, we will give evidence of how the involvement of BDNF in the pathogenesis of brain glioblastoma has emerged, thus opening new avenues for the treatment of this deadly cancer.

Ruta graveolens as a potential source of neuroactive compounds to promote and restore neural functions.

Nutraceuticals had always been known for their therapeutic effects in ancient medicine and had been the primary healing remedy until the introduction of modern chemistry and pharmacology. However, their use has not been dismissed but actually is acquiring a new acclamation among the scientific community especially for their efficacy on the Central Nervous System (CNS). Molecular mechanisms of the most common neurodegenerative diseases are now being uncovered and along with that the molecules that drive the neurodegenerative processes. It is not surprising that some natural compounds can interact with those molecules and interfere with the pathological pathways halting the cascades that ultimately lead to neuronal cell death. The plant Ruta graveolens has gained increased attention in medicinal chemistry due to its beneficial role to treat a variety of human diseases and also because of the presence of a huge number of compounds belonging to different classes of natural products, including neuroactive compounds potentially able to promote neuroprotection. Among all the components of the plant extract, rutin - which is highly, if not the most, abundant - positively interacts with the neurophysiology of the CNS too, being particularly efficient against neurotoxicity. Rutin, has proven to be protective in a variety of experimental settings of neurodegeneration. Finally, it has been shown that the water extract of Ruta graveolens (RGWE) induces death of glioblastoma cells but not of neuronal cells. Moreover, it also fosters cell cycle re-entry and differentiation of neuronal cells. This peculiarity represents a promising tool to promote neural plasticity in pathological conditions.

Molecular Regulation in Dopaminergic Neuron Development. Cues to Unveil Molecular Pathogenesis and Pharmacological Targets of Neurodegeneration.

The relatively few dopaminergic neurons in the mammalian brain are mostly located in the midbrain and regulate many important neural functions, including motor integration, cognition, emotive behaviors and reward. Therefore, alteration of their function or degeneration leads to severe neurological and neuropsychiatric diseases. Unraveling the mechanisms of midbrain dopaminergic (mDA) phenotype induction and maturation and elucidating the role of the gene network involved in the development and maintenance of these neurons is of pivotal importance to rescue or substitute these cells in order to restore dopaminergic functions. Recently, in addition to morphogens and transcription factors, microRNAs have been identified as critical players to confer mDA identity. The elucidation of the gene network involved in mDA neuron development and function will be crucial to identify early changes of mDA neurons that occur in pre-symptomatic pathological conditions, such as Parkinson's disease. In addition, it can help to identify targets for new therapies and for cell reprogramming into mDA neurons. In this essay, we review the cascade of transcriptional and posttranscriptional regulation that confers mDA identity and regulates their functions. Additionally, we highlight certain mechanisms that offer important clues to unveil molecular pathogenesis of mDA neuron dysfunction and potential pharmacological targets for the treatment of mDA neuron dysfunction.

Headaches in the medieval Medical School of Salerno.

PREMISE: Headaches are a serious public health concern of our days, affecting about 50% of the world's adult population. However, such a plague is not limited to the modern era, since ancient archaeological, written, religious and cultural evidences testify to countless attempts to face such disorders from medical, neurosurgical, psychological and sociological perspectives. BACKGROUND: Substantially, the Hippocratic and Galenic theories about headache physiopathology remained predominant up to the 17th century, when the vascular theory of migraine was introduced by Thomas Willis and then evolved into the actual neurovascular hypothesis. The medieval Medical School of Salerno, in southern Italy, where the Greco-Roman medical doctrine was deeply affected by the medio-oriental influence, gave particular attention to both prevention and treatment of headaches. CONCLUSION: The texts of the School, a milestone in the literature of medicine, translated into different languages and widespread throughout Europe for centuries, provide numerous useful recipes and ingredients with an actually proven pharmacological efficacy.

Mineralcorticoid Receptor Antagonist Withdrawal for Hyperkalemia and Mortality in Patients with Heart Failure.

BACKGROUND: Hyperkalemia is one of the most frequent side effects related to renin-angiotensin-aldosterone system (RAAS) inhibition, and can influence optimization of heart failure (HF) therapy. AIM: To evaluate the occurrence of hyperkalemia in a series of outpatients with chronic HF and its relationship with RAAS inhibitor therapy. METHOD: We evaluated consecutive outpatients with HF and a reduced left ventricular ejection fraction. The incidence of hyperkalemia and consequent changes in RAAS inhibitor therapy were evaluated for each patient. RESULTS: A history of hyperkalemia or at least 1 episode of hyperkalemia during follow-up was observed in 104 of 351 patients. Hyperkalemia mainly influenced mineralocorticoid receptor antagonist (MRA) therapy and, among patients with hyperkalemia, not taking MRA was associated with a greater risk of death on univariate analysis (HR = 6.39; 95% CI 2.76-14.79, p < 0.001) and multivariate analysis (HR = 5.24; 95% CI 1.87-14.72, p = 0.002) after correction for age, ischemic cardiomyopathy, diabetes, systolic arterial pressure, New York Heart Association class 3, left ventricular ejection fraction, presence of hyponatremia, glomerular filtration rate calculated by the EPI formula, and presence of N-terminal pro-B-type natriuretic peptide >1,000 pg/mL. CONCLUSION: The occurrence of hyperkalemia is common among outpatients with HF and it is the main cause of MRA withdrawal, which is associated with a worse prognosis. In this setting, the possibility of managing hyperkalemia using new classes of drugs could allow continuation of MRA therapy.

HUVEC Tube-formation Assay to Evaluate the Impact of Natural Products on Angiogenesis.

Angiogenesis is a phenomenon that includes different processes, such as endothelial cell proliferation, differentiation, and migration, that lead to the formation of new blood vessels and involve several signal transduction pathways. Here we show that the tube formation assay is a simple in vitro method to evaluate the impact of natural products on angiogenesis and to investigate the molecular mechanisms involved. In particular, in the presence of the water extract of Ruta graveolens (RGWE), endothelial cells are no longer able to form a cell-cell network and that the RGWE effects on human umbilical vein endothelial cell (HUVEC) tube formation is abolished by the constitutive activation of MEK.

Histone Deacetylase Inhibitors Impair Vasculogenic Mimicry from Glioblastoma Cells.

Glioblastoma (GBM), a high-grade glioma (WHO grade IV), is the most aggressive form of brain cancer. Available treatment options for GBM involve a combination of surgery, radiation and chemotherapy but result in a poor survival outcome. GBM is a high-vascularized tumor and antiangiogenic drugs are widely used in GBM therapy as adjuvants to control abnormal vasculature. Vasculogenic mimicry occurs in GBM as an alternative vascularization mechanism, providing a means whereby GBM can escape anti-angiogenic therapies. Here, using an in vitro tube formation assay on Matrigel®, we evaluated the ability of different histone deacetylase inhibitors (HDACis) to interfere with vasculogenic mimicry. We found that vorinostat (SAHA) and MC1568 inhibit tube formation by rat glioma C6 cells. Moreover, at sublethal doses for GBM cells, SAHA, trichostatin A (TSA), entinostat (MS275), and MC1568 significantly decrease tube formation by U87MG and by patient-derived human GBM cancer stem cells (CSCs). The reduced migration and invasion of HDACis-treated U87 cells, at least in part, may account for the inhibition of tube formation. In conclusion, our results indicate that HDACis are promising candidates for blocking vascular mimicry in GBM.

Tissue-specific and mosaic imprinting defects underlie opposite congenital growth disorders in mice.

Differential DNA methylation defects of H19/IGF2 are associated with congenital growth disorders characterized by opposite clinical pictures. Due to structural differences between human and mouse, the mechanisms by which mutations of the H19/IGF2 Imprinting Control region (IC1) result in these diseases are undefined. To address this issue, we previously generated a mouse line carrying a humanized IC1 (hIC1) and now replaced the wildtype with a mutant IC1 identified in the overgrowth-associated Beckwith-Wiedemann syndrome. The new humanized mouse line shows pre/post-natal overgrowth on maternal transmission and pre/post-natal undergrowth on paternal transmission of the mutation. The mutant hIC1 acquires abnormal methylation during development causing opposite H19/Igf2 imprinting defects on maternal and paternal chromosomes. Differential and possibly mosaic Igf2 expression and imprinting is associated with asymmetric growth of bilateral organs. Furthermore, tissue-specific imprinting defects result in deficient liver- and placenta-derived Igf2 on paternal transmission and excessive Igf2 in peripheral tissues on maternal transmission, providing a possible molecular explanation for imprinting-associated and phenotypically contrasting growth disorders.

Ruta graveolens water extract inhibits cell-cell network formation in human umbilical endothelial cells via MEK-ERK1/2 pathway.

Angiogenesis is a process encompassing several steps such as endothelial cells proliferation, differentiation and migration to form a vascular network, involving different signal transduction pathways. Among these, ERK1/2 signaling mediates VEGF-dependent signaling pathway. Here we report that the water extract of Ruta graveolens (RGWE), widely known as a medicinal plant, is able to impair in a dose-dependent manner, cell network formation without affecting cell viability. Biochemical analysis showed that the major component of RGWE is rutin, unable to reproduce RGWE effect. We found that RGWE inhibits ERK1/2 phosphorylation and that this event is crucial in cell network formation since the transfection of HUVEC with a constitutively active MEK (caMEK), the ERK1/2 activator, induces a robust cell network formation as compared to untransfected and/or mock transfected cells and, more importantly, caMEK transfected cells became unresponsive to RGWE. Moreover, RGWE inhibits VEGF and nestin gene expression, necessary for vessel formation, and the caMEK transfection induces their higher expression. In conclusion, we report that RGWE is able to significantly impair vessels network formation without affecting cell viability, preventing ERK1/2 activation and, in turn, down-regulating VEGF and nestin expression. These findings point to RGWE as a potential therapeutic tool capable to interfere with pathologic angiogenesis.

Functional characterization of the neuron-restrictive silencer element in the human tryptophan hydroxylase 2 gene expression.

Tryptophan hydroxylase 2 (TPH2) is the key enzyme in the synthesis of neuronal serotonin. Although previous studies suggest that TPH2 neuron-restrictive silencer element (NRSE) functions as a negative regulator dependent on neuron-restrictive silencer factor (NRSF) activity, the underlying mechanisms are yet to be fully elucidated. Here, we show a detailed analysis of the NRSE-mediated repression of the human TPH2 (hTPH2) promoter activity in RN46A cells, a cell line derived from rat raphe neurons. Quantitative real-time RT-PCR analysis revealed the expression of serotonergic marker genes (Mash1, Nkx2.2, Gata2, Gata3, Lmx1b, Pet-1, 5-Htt, and Vmat2) and Nrsf gene in RN46A cells. Tph1 mRNA is the prevalent form expressed in RN46A cells; Tph2 mRNA is also expressed but at a lower level. Electrophoretic mobility shift assays and reporter assays showed that hTPH2 NRSE is necessary for the efficient DNA binding of NRSF and for the NRSF-dependent repression of the hTPH2 promoter activity. The hTPH2 promoter activity was increased by knockdown of NRSF, or over-expression of the engineered NRSF (a dominant-negative mutant or a DNA-binding domain and activation domain fusion protein). MS-275, a class I histone deacetylase (HDAC) inhibitor, was found to be more potent than MC-1568, a class II HDAC inhibitor, in enhancing the hTPH2 promoter activity. Furthermore, treatment with the ubiquitin-specific protease 7 deubiquitinase inhibitors, P-22077 or HBX 41108, increased the hTPH2 promoter activity. Collectively, our data demonstrate that the hTPH2 NRSE-mediated promoter repression via NRSF involves class I HDACs and is modulated by the ubiquitin-specific protease 7-mediated deubiquitination and stabilization of NRSF.