Eur J Pharmacol. 2003 Sep 5;477(1):59-68.
Nitric oxide-releasing aspirin inhibits vasoconstriction in perfused tail artery of normotensive and spontaneously hypertensive rats.
Rossoni G, Manfredi B, Del Soldato P, Polvani G, Berti F. Department of Pharmacological Sciences, University of Milan, Milan, Italy.
The aim of this study was to investigate the capacity of the 2-(acetyloxy)benzoic acid 3-(nitrooxymethyl)phenyl ester (NCX 4016), a nitric oxide (NO)-releaser derivative of aspirin, to decrease blood pressure in spontaneously hypertensive rats (SHR) and to counteract the adrenergic vasoconstriction in perfused tail artery of these animals. Oral treatment for 10 consecutive days with NCX 4016 (100 micromol/kg) in SHR and their genetic controls Wistar Kyoto (WKY) rats resulted in a reduction of blood pressure in SHR but not in WKY rats. In SHR, the NCX 4016 treatment increased the serum nitrite/nitrate and diminished the serum thromboxane B2, whereas aspirin did not change blood pressure but abolished the serum thromboxane B2. Perfused tail arteries excised from vehicle-treated SHR exhibited a significant impairment of endothelium-dependent vasorelaxant function. These vessels, prepared from SHR or WKY rats treated orally with NCX 4016 (10, 30 and 100 micromol/kg for 7 consecutive days), revealed a dose-dependent decrease in vasoconstriction in response to transmural nerve stimulation and norepinephrine, whereas aspirin was ineffective. Furthermore, in tail arteries of both SHR and WKY rats treated orally with NCX 4016 (100 micromol/kg for 7 consecutive days), the cGMP increased significantly. In conclusion, NCX 4016, by releasing NO and increasing cGMP in vascular tissue, reduces sympathetic-mediated vasoconstriction in resistance vessels and lowers blood pressure in SHR.
Inflamm Res. 2003 Sep;52(9):359-65.
Nitric oxide-releasing aspirin protects gastric mucosa against ethanol damage in rats with functional ablation of sensory nerves.
Konturek PC, Brzozowski T, Kania J, Konturek SJ, Hahn EG. First Department of Medicine, University Erlangen-Nuernberg, D-91064 Erlangen, Germany.
OBJECTIVE AND DESIGN: The aim of the present study was to investigate, whether sensory nerves are involved in the gastroprotection induced by NO releasing non-steroidal anti-inflammatory drugs (NO-NSAID). MATERIAL: Studies were performed in Wistar rats with intact or inactivated sensory nerves by pretreatment with large dose of capsaicin (125 mg/kg sc). TREATMENTS: Acute gastric lesions were induced by 100% ethanol (100% EtOH). 1 h before exposure to 100% EtOH, rats received vehicle, aspirin (ASA) or NO-releasing aspirin (NO-ASA) in the same dose (50 mg/kg). The animals were killed 1 h after exposure to 100% EtOH. METHODS: Determinations were made of gastric mucosal injury, mucosal gastric blood flow, mucosal mRNA expression of glutathione peroxidase (GPx), zinc copper superoxide dismutase (SOD) and heat shock protein (HSP70) by RT-PCR and protein expression for HSP70 by Western blotting. RESULTS: Pretreatment with ASA aggravated the acute gastric injury induced by 100% EtOH, whereas pre-treatment with NO-ASA led to a significant reduction in this injury. Administration of 100% EtOH was accompanied by a pronounced upregulation of HSP70, which was reduced by ASA, but enhanced by NO-ASA application. Sensory deactivation with capsaicin enhanced acute ethanol lesions and led to a significant attenuation in HSP70 expression. In contrast to ASA, NO-ASA attenuated gastric mucosal lesions and significantly upregulated HSP70 expression despite blockade of sensory nerves. NO-ASA, but not ASA, caused an upregulation of SOD and GPx mRNA in gastric mucosa with or without sensory denervation. CONCLUSIONS: NO-ASA protects gastric mucosa even after blockade of sensory nerves due to the upregulation of HSP70 expression and attenuation of the oxidative injury resulting from strong upregulation of genes for antioxidant enzymes.
Proc Natl Acad Sci U S A. 2003 Sep 16;100(19):10937-41. Epub 2003 Sep 5.
Interaction of a selective cyclooxygenase-2 inhibitor with aspirin and NO-releasing aspirin in the human gastric mucosa.
Fiorucci S, Santucci L, Wallace JL, Sardina M, Romano M, del Soldato P, MorelliA. Clinica di Gastroenterologia ed Epatologia, Dipartimento di Medicina Clinica e Sperimentale, Universita di Perugia, Italy.
In addition to inhibiting cyclooxygenase (COX)-1-derived prostanoid biosynthesis, aspirin acetylates COX-2, enabling the conversion of arachidonic acid to 15(R)-epi lipoxin A4, or aspirin-triggered lipoxin (ATL). Selective COX-2 inhibitors block ATL formation and exacerbate mucosal injury in rats treated with aspirin. In the present study, we have examined whether inhibition of COX-2 activity in healthy volunteers taking aspirin exacerbates gastric mucosal injury and if such an effect would be prevented by NCX-4016, a NO-releasing derivative of aspirin. Thirty-two volunteers were randomized to receive 2 wk of treatment with NCX-4016 (800 mg twice a day) or aspirin (100 mg once a day) alone or in combination with 200 mg of celecoxib twice a day. Mucosal damage was assessed by endoscopy. The mean mucosal injury score was 5.8 +/- 1.8 in subjects treated with aspirin and 2.4 +/- 0.7 (P < 0.01 vs. aspirin) in subjects treated with NCX-4016. Administration of celecoxib increased the injury score in volunteers treated with aspirin (9.9 +/- 1.9) but not in subjects taking NCX-4016 (1.5 +/- 0.8). Aspirin and NCX-4016 caused a comparable suppression of serum thromboxane B2 levels and increased urinary excretion of ATL. Celecoxib inhibited endotoxin-induced prostaglandin E2 generation in whole blood by approximately 80% and abolished ATL formation. These findings suggests that (i) aspirin and NCX-4016 trigger ATL formation in humans, (ii) celecoxib inhibits ATL formation and exacerbates the mucosal injury caused by low doses of aspirin, and (iii) the NO-donating moiety of NCX-4016 protects the gastric mucosa even in the presence of suppression of COX-1 and COX-2.
Curr Opin Investig Drugs. 2003 Sep;4(9):1126-39.
NCX-4016 NicOx.
Di Napoli M, Papa F. Neurological Section, SMDN-Center for Cardiovascular Medicine and Cerebrovascular Disease Prevention, 41 Via Trento, I-67039-Sulmona, AQ, Italy.
NCX-4016 is a nitric oxide-aspirin conjugate non-steroidal anti-inflammatory drug that is under investigation by NicOx for the potential treatment of cardiovascular disorders and colon cancer. In April 2002, a phase II clinical trial was initiated in symptomatic peripheral arterial disease, and in March 2003, the University of Michigan was awarded a grant by the NIH to conduct a phase II trial in individuals at risk of colon cancer.
