Mazzini S.,University of Milan |
Scaglioni L.,University of Milan |
Animati F.,Menarini Ricerche |
Mondelli R.,University of Milan
Bioorganic and Medicinal Chemistry | Year: 2010
Among the disaccharide derivatives of the antitumor anthracycline doxorubicin, sabarubicin (Men10755) is more active and less cytotoxic than doxorubicin. It showed a strong in vivo antitumor activity in all preclinical models examined, in conjunction with a better tolerability, and is now in phase II clinical trials. The interaction of sabarubicin and Men10749 (a similar disaccharide with a different configuration at C-4′ of the proximal sugar) with the hexanucleotides d(CGTACG)2 and d(CGATCG)2 was studied by a combined use of 2D-1H and 31P NMR techniques. Both 1H and 31P chemical shifts of imino protons and phosphates allowed to established the intercalation sites between the CG base pairs, as it occurs for other anthracyclines of the series. The dissociation rate constants (koff) of the slow step of the intercalation process were measured for Men10755 and Men10749, by NMR NOE-exchange experiments. The increase of koff, with respect of doxorubicin, showed that the intercalation process is significantly faster for both drugs, leading to an average residence time for sabarubicin into d(CGTACG)2 sixfold shorter than for doxorubicin. This could give account of both higher cytoplasmic/nuclear ratio and lower cellular uptake of sabarubicin in comparison with doxorubicin and accordingly of the lower cytotoxicity of these disaccharide analogues. A relevant number of NOE interactions allowed the structure of the complexes in solution to be derived through restrained MD calculations. NMR-DOSY experiments were performed with several drug/oligonucleotide mixtures in order to determine the structure and the dimension of the aggregates. © 2010 Elsevier Ltd. All rights reserved.
Marampon F.,University of LAquila |
Gravina G.L.,University of LAquila |
Scarsella L.,University of LAquila |
Festuccia C.,University of LAquila |
And 8 more authors.
Journal of Hypertension | Year: 2013
Objective: Oxidative stress has been linked to endothelial dysfunction and angiotensin II stimulates the reactive oxygen species production contributing to several cardiovascular diseases. We have studied the chain of events induced by angiotensin-converting-enzyme (ACE) activation in vascular umbilical vein endothelial cells (HUVECs) by using an ACE inhibitor such as zofenoprilat. Methods: We used specific assay to measure the superoxide anion production, tetrazolium bromide (MTT) assay for cell viability, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay for cell apoptosis, and western blot for protein analysis in the study. Results: Zofenoprilat counteracts the superoxide anion production and cell apoptosis induced by angiotensin I treatment by blocking the extrinsic caspase cascade, NF-kB and p38 activation. p38 inhibitor SB203580 reverted the angiotensin II oxidant effects while the p38 constitutively activation, by MKK6 transfection, abrogated the zofenoprilat effects. Characterizing the zofenoprilat downstream effector we found that zofenoprilat reverted the SirT-1 downregulation induced by angiotensin II. p38 activation by angiotensin II was strictly correlated with SirT1 protein downregulation; SB203580 significantly prevented SirT1 downregulation induced by angiotensin II while the p38 constitutive activation abolished SIRT1 protein basal levels. p38 directly bound SirT1 sequestering it in the cytoplasm. SirT1 inhibition by sirtinol annulled zofenoprilat action while SirT1 overexpression reverted the cytotoxic effects of angiotensin II. Finally, zofenoprilat negatively controlled angiotensin I receptor protein expression through SirT1. Conclusion: The p38-SirT1 axis is found markedly relevant in modulating the cardiovascular benefit deriving from ACE-inhibitors and might represent a novel target for innovative drugs in cardiovascular prevention. © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins.
Strege P.R.,Mayo Medical School |
Sha L.,Mayo Medical School |
Beyder A.,Mayo Medical School |
Bernard C.E.,Mayo Medical School |
And 5 more authors.
American Journal of Physiology - Gastrointestinal and Liver Physiology | Year: 2010
Antispasmodics are used clinically to treat a variety of gastrointestinal disorders by inhibition of smooth muscle contraction. The main pathway for smooth muscle Ca2+ entry is through L-type channels; however, there is increasing evidence that T-type Ca+ channels also play a role in regulating contractility. Otilonium bromide, an antispasmodic, has previously been shown to inhibit L-type Ca2+ channels and colonic contractile activity. The objective of this study was to determine whether otilonium bromide also inhibits T-type Ca2+ channels. Whole cell currents were recorded by patch-clamp technique from HEK293 cells transfected with cDNAs encoding the T-type Ca2+ channels, CaV3.1 (α1G), CaV3.2 (α1H), or CaV3.3 (α1I) alpha subunits. Extracellular solution was exchanged with otilonium bromide (10-8 to 10-5 M). Otilonium bromide reversibly blocked all T-type Ca2+ channels with a significantly greater affinity for CaV3.3 than CaV3.1 or CaV3.2. Additionally, the drug slowed inactivation in Ca V3.1 and CaV3.3. Inhibition of T-type Ca2+ channels may contribute to inhibition of contractility by otilonium bromide. This may represent a new mechanism of action for antispasmodics and may contribute to the observed increased clinical effectiveness of antispasmodics compared with selective L-type Ca2+ channel blockers. Copyright © 2010 the American Physiological Society.
Carotenuto A.,University of Naples Federico II |
Auriemma L.,University of Naples Federico II |
Merlino F.,University of Naples Federico II |
Yousif A.M.,University of Naples Federico II |
And 9 more authors.
Journal of Medicinal Chemistry | Year: 2014
We have optimized 1 (P5U) and urantide, two important ligands at the h-UT receptor, designing several analogues by the exchange of the Tyr9 residue with different unnatural aromatic amino acids. This study allowed us to discover novel ligands with improved activity. In particular, the replacement of the Tyr9 residue by (pCN)Phe or (pNO2)Phe within the urantide sequence led to compounds 13 (UPG-83) and 15 (UPG-95), respectively, which showed pure antagonist activity toward UT receptor in a rat aorta bioassay. More interestingly, the replacement of the Tyr9 in 1 sequence with the Btz or the (3,4-Cl)Phe residues led to superagonists 6 (UPG-100) and 10 (UPG-92) with pEC50 values at least 1.4 log higher than that of 1, being the most potent UT agonists discovered to date. Compounds 10 and 13 showed also a good stability in a serum proteolytic assay. These ligands represent new useful tools to further characterize the urotensinergic system in human physiopathology. © 2014 American Chemical Society.
Pfisterer J.,Klinik fur Gynakologie und Geburtshilfe Stadtisches Klinikum Solingen |
Harter P.,Klinikum Essen Mitte |
Simonelli C.,Menarini Ricerche |
Peters M.,Klinik fur Gynakologie und Geburtshilfe Stadtisches Klinikum Solingen |
And 3 more authors.
Expert Opinion on Biological Therapy | Year: 2011
Introduction: Ovarian cancer (OC) is the fifth most common cancer in women. Unfortunately, more than 70% of cases are detected at an advanced stage with a risk of recurrence, after front line therapy, of over 75%. The need for new therapeutic strategies is extremely high. Areas covered: The development status and the possible role of specific immunotherapy of abagovomab are discussed in the context of the possible therapeutic options for maintenance therapy in advanced OC. An overview of abagovomab, generation and mechanism of action, Phase I/II results and the status of the Phase II/III ongoing trial is given. Expert opinion: Abagovomab stimulates the humoral immune response and the cell-mediated immune response in the studies conducted to date. In the proof of concept (POC) study abagovomab prolonged overall survival in those OC recurrent patients who showed an immune response. Abagovomab has an excellent safety and tolerability profile. These characteristics make abagovomab an optimal candidate for a maintenance treatment for OC patients after frontline therapy. The final results of the Phase II/III pivotal study evaluating abagovomab in this setting will be available in the first half of 2011. © 2011 Informa UK, Ltd.