Catalioto R.-M.,Menarini Ricerche SpA |
Maggi C.A.,Menarini Ricerche SpA |
Giuliani S.,Menarini Ricerche SpA
Current Medicinal Chemistry | Year: 2011
The intestinal epithelial monolayer constitutes a physical and functional barrier between the organism and the external environment. It regulates nutrients absorption, water and ion fluxes, and represents the first defensive barrier against toxins and enteric pathogens. Epithelial cells are linked together at the apical junctional complex by tight junctions that reduce the extracellular space and the passage of charge entities while forming a physical barrier to lipophilic molecules. Cultured intestinal epithelial cells have been extensively used to study intestinal absorption of newly synthesized drugs and the regulation of tight junctions structure and function. In vitro mild irritants, proinflammatory cytokines, toxins and pathogens, and adverse environmental conditions open tight junctions and increase paracellular permeability, an effect often accompanied by immune activation of the enterocytes. Conversely, inhibition of proinflammatory cytokines, exposure to growth factors and probiotics, among others, exert a protective effect. Impaired barrier function results from activation of signalling pathways that lead to alteration of junctional proteins expression and/or distribution. In vivo, intestinal barrier dysfunction is associated with various intestinal and non-intestinal disorders including inflammatory bowel disease, celiac disease, and diarrhoeal infection. This review will describe the current knowledge of the mechanisms regulating tight junctions and intestinal permeability, how these findings have lead to a better understanding of barrier alteration in human intestinal disorders, and what the emerging therapies to treat these pathologies are. © 2011 Bentham Science Publishers Ltd.
Vannucchi M.G.,University of Florence |
Evangelista S.,Menarini Ricerche SpA
Biomolecular Concepts | Year: 2013
The neurokinin receptors are G-protein-linked receptors; three distinct molecules, called neurokinin-1, neurokinin-2, and neurokinin-3 receptors, have been identified. Their physiological ligands are the tachykinins, which, in the mammalian gut, correspond to substance P, neurokinin A, and neurokinin B. In this apparatus, the main source of tachykinins is represented by intrinsic neurons located either in the myenteric plexus and projecting mainly to the muscle coat, or in the submucous plexus and projecting to the mucosa and submucosal blood vessels. The availability of specific antibodies has allowed identifying the sites of distribution of the neurokinin receptors in the gut, and important differences have been found among cell types and animal species. The complexity of the receptor distribution, either intraspecies or interspecies, is in agreement with the variegated picture coming out from physiological and pharmacological experiments. Interestingly, most of the knowledge on the tachykinin systems has been obtained from pathological conditions. Here, we tried to collect the main information available on the cellular distribution of the neurokinin receptors in the gut wall in the attempt to correlate their cell location with the several roles the tachykinins seem to play in the gastrointestinal apparatus.
Evangelista S.,Menarini Ricerche SpA
Progress in Drug Research | Year: 2014
Calcitonin gene-related peptide (CGRP), a 37 aminoacid-residue peptide, is a marker of afferent fibers in the upper gastrointestinal tract, being almost completely depleted following treatment with the selective neurotoxin capsaicin that targets these fibers via transient receptor potential vanilloid type-1 (TRPV-1). It is widely distributed in the peripheral nervous system of mammals where it is present as α isoform, while intrinsic neurons of the enteric nervous systems express predominantly CGRP-β. Many gastrointestinal functions involve CGRP-containing afferent fibers of the enteric nervous system such as defense against irritants, intestinal nociception, modulation of gastrointestinal motility and secretion, and healing of gastric ulcers. The main effects on stomach homeostasis rely on local vasodilator actions during increased acid-back diffusion. In humans, release of CGRP through the activation of TRPV-1 has been shown to protect from gastric damage induced by several stimuli and to be involved in gastritis. In both dyspepsia and irritable bowel syndrome the repeated stimulation of TRPV-1 induced an improvement in epigastric pain of these patients. The TRPV-1/CGRP pathway might be a novel target for therapeutics in gastric mucosal injury and visceral sensitivity. © Springer Basel 2014.
Evangelista S.,Menarini Ricerche SpA
Expert Review of Clinical Pharmacology | Year: 2015
Capsaicin, a pharmacologically active agent found in chili peppers, causes burning and itching sensation due to binding at the transient receptor potential vanilloid-1 (TRPV-1) receptor, a polymodal receptor critical to the sensing of a variety of stimuli (e.g., noxious heat, bidirectional pH), and subsequent activation of polymodal C and A-δ nociceptive fibers. Acutely, TRPV-1 activation with peripheral capsaicin produces pronociceptive effects, which extends to the development of hyperalgesia and allodynia. However, capsaicin has been reported to display antinociceptive properties as well, largely through TRPV-1-dependent mechanisms. Local application of high concentration of capsaicin is used for neuropathic pain and repeated stimulation of TRPV-1 induced an improvement of epigastric pain in irritable bowel syndrome and dyspepsia patients by desensitization of nociceptive pathways. New TRPV-1 agonists are currently under preclinical study and TRPV-1 antagonists are in early clinical development as analgesics. The TRPV-1 pathway might be a novel target for therapeutics in pain sensitivity. © 2015 Informa UK, Ltd.
Gomis A.,University Miguel Hernández |
Meini S.,Menarini Ricerche S.p.A. |
Miralles A.,University Miguel Hernández |
Valenti C.,Menarini Ricerche S.p.A. |
And 3 more authors.
Osteoarthritis and Cartilage | Year: 2013
Objective: The aim of this study was to determine in intact and inflamed knee joints of the rat, the effect of the bradykinin (BK) B2 receptor antagonist fasitibant (MEN16132) on nociceptor mechanosensitivity and hyperalgesia. Methods: Joint afferent sensory fibers of the medial articular nerve of anesthetized animals were electrophysiologically recorded, measuring nerve impulse activity evoked by passive innocuous and noxious movements of the joint, in intact and kaolin and carrageenan-injected joints. Knee joints of rats were also acutely inflamed by intra-articular injection of carrageenan alone. Long term duration of fasitibant antinociceptive effects were behaviorally evaluated using the incapacitance test. Results: BK (100μM) injected into the saphenous artery, induced excitation and sensitization of multi- and single unit recordings. Fasitibant (300μM) injected prior to BK, reduced its excitatory effects as well as the overall increase of movement-evoked activity resulting from repeated injections of BK. Fasitibant did not affect movement-evoked activity of sensory fibers of intact, non-inflamed knee joints. Intra-articular fasitibant (100μg/knee) significantly reduced the carrageenan-induced inflammatory hyperalgesia measured with the incapacitance test up to four days after treatment. This antinociceptive effect was not obtained with systemic endovenous injection of the drug. Conclusions: Fasitibant prevents B2 receptor-mediated activation and sensitization of peripheral joint afferents and the ensuing inflammatory hyperalgesia, and may be a useful, novel drug for arthritis pain treatment. © 2013 Osteoarthritis Research Society International.
Evangelista S.,Menarini Ricerche SpA
Gastroenterology Research and Practice | Year: 2012
It is known that irritable bowel syndrome (IBS) is a chronic disease of cyclic nature characterized by recurrent symptoms. IBS patients should receive, as initial therapeutic approach a short course of treatment which, if effective, has the additional value of confirming the diagnosis. Long-term treatment should be reserved to diagnosed IBS patients with recurrent symptoms. Clinical trials with stabilized therapies and new active treatments showed an improvement of the symptoms over placebo that is often time-dependent but with high relapse rates (around 40-50 when stopping treatment). Relapse is not always immediate after stopping treatment and the recent data from OBIS trial with otilonium bromide or with psychotherapy, showed that due to different chemico-physical characteristics of the drugs or the psychosomatic impact to the disease not all treatment gave the same relapsing rate if compared to placebo. Results of IBS clinical trials with different therapies tailored to the patient needs indicate that a cyclic treatment therapy is advisable to counteract the nature of the disease. Copyright © 2012 Stefano Evangelista.
Mutolo D.,University of Florence |
Bongianni F.,University of Florence |
Evangelista S.,Menarini Ricerche SpA |
Cinelli E.,University of Florence |
Pantaleo T.,University of Florence
Journal of Cardiovascular Pharmacology and Therapeutics | Year: 2010
Cough is the most common symptom reported by patients in a primary care setting and is one of the most frequent secondary effects recorded during treatment with angiotensin-converting enzyme (ACE) inhibitors. The aim of the current study was to analyze potential differences in cough induction between 2 structurally different ACE inhibitors, namely zofenopril, which has a sulphydryl moiety, and ramipril, which has a carboxyl moiety. The cough reflex was induced by chemical (citric acid) and/or mechanical stimulation of the tracheobronchial tree in awake and anesthetized rabbits. Intravenous injection of the active compounds of the 2 ACE inhibitors, zofenoprilat (288 nmol/kg) and ramiprilat (129 nmol/kg), caused similar hypotensive effects in anesthetized rabbits. None of the studied cough-related variables changed in response to ACE inhibitor administration, with the exception of the number of coughs. Ramiprilat, but not zofenoprilat, increased the cough response induced by both mechanical and chemical stimulation (1 mol/L citric acid aerosol) of the tracheobronchial tree. In awake animals, zofenoprilat- or vehicle-treated rabbits did not show any significant changes in the number of coughs induced by 1 mol/L citric acid aerosol compared to their respective basal values (from 15.2 ± 2.3 to 13.1 ± 1.3 and from 16.1 ± 4.9 to 15.8 ± 4.3, respectively). Conversely, ramiprilat resulted in a significant increase in the number of coughs (from 21.1 ± 2.6 to 34.9 ± 3.5; P <.01). These findings confirm that there are differences in the cough potentiation effect induced by different ACE inhibitors. The low rate of cough seen with zofenoprilat may be related to its ability to induce a lower accumulation of bradykinin and prostaglandins at the lung level. © 2010 The Author(s).
Bucci M.,University of Naples Federico II |
Vellecco V.,University of Naples Federico II |
Cantalupo A.,University of Naples Federico II |
Brancaleone V.,University of Basilicata |
And 5 more authors.
Cardiovascular Research | Year: 2014
AimsTherapeutic use of sulfhydrylated inhibitor S-zofenopril has raised different hypotheses regarding the role played by its thiol group in the beneficial clinical effects exerted compared with other angiotensin-converting enzyme (ACE) inhibitors. Here, we investigated hydrogen sulfide (H2S) pathway as accountable for extra-beneficial effects in vascular function.Methods and resultsSpontaneously hypertensive rat (SHRs) and control Wistar Kyoto (WKY) rats were treated with either S-zofenopril or enalapril in vivo. Aorta and carotid were harvested and ex vivo vascular reactivity to acetylcholine (Ach) and l-cysteine (l-cys) assessed. Cystathionine-β- synthase (CBS), cystathionine-γ-lyase (CSE), and 3-mercaptosulfur- transferase (3MST) expression, as well as H2S levels, were evaluated in both vascular tissues. The vascular response to Ach in both carotid and aorta was impaired in SHR (∼30%, P < 0.001). S-zofenopril, but not enalapril, restored this response, while l-cys-induced relaxation was enhanced. CSE expression in vessels and tissue/plasma H2S levels were restored to WKY values in SHRs receiving S-zofenopril. In contrast, CBS and 3MST expression were not modified by treatments. S-zofenoprilat, an active metabolite of S-zofenopril, releases H2S in a 'cell-free' assay and it directly relaxed vessels in vitro in a concentration-dependent manner (P < 0.001). In vivo administration of R-zofenoprilat diasteroisomer, which does not inhibit ACE, did not modify blood pressure; nonetheless, it retained the beneficial effect on SHR vascular function as well as restored plasma/tissue H2S levels.ConclusionOur findings establish that S-zofenopril improves vascular function by potentiating the H2S pathway in a model of spontaneous hypertension. This novel mechanism, unrelated to ACE inhibition and based on H2S release, could explain the beneficial effects of sulfhydrylated ACE inhibitors reported in the clinical literature. © 2014 The Author.
Bressan A.,Menarini Ricerche S.p.A |
Bozzo F.,Menarini Ricerche S.p.A |
Maggi C.A.,Menarini Ricerche S.p.A |
Binaschi M.,Menarini Ricerche S.p.A
Disease Markers | Year: 2013
The human cancer antigen 125 (CA125) is over-expressed in epithelial ovarian cancer cells and it plays a role in the pathogenesis of ovarian cancer. This protein presents a repeat region containing up to sixty tandem repeat units. The anti-CA125 monoclonal antibodies have been previously classified into three groups: two major families, the OC125-like antibodies and M11-like antibodies, and a third group, the OV197-like antibodies. A model in which a single repeat unit contains all the epitopes for these antibodies has been also proposed, even if their exact position is still undetermined. In the present work, the affinities of the monoclonal antibodies, representative of the three families, have been investigated for different CA125-recombinant repeats through Western blot analysis. Different patterns of antibody recognition for the recombinant repeats show that CA125 epitopes are not uniformly distributed in the tandem repeat region of the protein. The minimal region for the recognition of these antibodies has been also individuated in the SEA domain through the subcloning of deleted sequences of the highly recognized repeat-25 (R-25), their expression as recombinant fragments in E. coli and Western blot analysis. Obtained data have been further confirmed by ELISA using the entire R-25 as coating antigen. © 2013-IOS Press and the authors. All rights reserved.
Traini C.,University of Florence |
Cipriani G.,University of Florence |
Evangelista S.,Menarini Ricerche SpA |
Santicioli P.,Menarini Ricerche SpA |
And 2 more authors.
Neurogastroenterology and Motility | Year: 2013
Background: Otilonium bromide (OB) is a quaternary ammonium derivative used for the treatment of intestinal hypermotility and is endowed with neurokinin2 receptor (NK2r) antagonist and Ca2+channel blocker properties. Therefore, the possibility that OB might play a role in the neurokinin receptor/Substance-P/nitric oxide (NKr/SP/NO) circuit was investigated after chronic exposition to the drug. Methods: Rats were treated with OB 2-20 mg kg-1 for 10 and 30 days. In the proximal colon, the expression and distribution of muscle NOsynthase 1 (NOS1), NK1r, NK2r, SP and Cav 1.2 subunit (for L-type Ca2+channel) and the spontaneous activity and stimulated responses to NK1r and NK2r agonists were investigated. Key Results: Immunohistochemistry showed a redistribution of NK1r and L-type Ca2+channel in muscle cells with no change of NK2r at 30 days, a significant increase in muscle NOS1 expression at 10 days and a significant decrease in the SP content early in the ganglia and later in the intramuscular nerve fibers. Functional studies showed no change in spontaneous activity but a significant increase in maximal contraction induced by NK1r agonist. Conclusions & Inferences: Chronic exposition to OB significantly affects the NKr/SP/NO circuit. The progressive decrease in SP-expression might be the consequence of the persistent presence of OB, the increase of NOS1 expression in muscle cells at 10 days in an attempt to guarantee an adequate NO production, and, at 30 days, the redistribution of the L-type Ca2+channel and NK1r as a sign to compensate the drug channel block by re-cycling both of them. The physiological data suggest NK1r hypersensitivity. © 2013 John Wiley & Sons Ltd.