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Stamm P, Kalinovic S, Oelze M, Steven S, Czarnowski A, Kvandova M, Bayer F, Reinhardt C, Münzel T, Daiber A. Mechanistic Insights into Inorganic Nitrite-Mediated Vasodilation of Isolated Aortic Rings under Oxidative/Hypertensive Conditions and S-Nitros(yl)ation of Proteins in Germ-Free Mice. Biomedicines 2022; 10:biomedicines10030730. [PMID: 35327532 PMCID: PMC8945819 DOI: 10.3390/biomedicines10030730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/11/2022] [Accepted: 03/16/2022] [Indexed: 02/07/2023] Open
Abstract
The prevalence and clinical importance of arterial hypertension are still growing. Inorganic nitrite (NO2-) represents an attractive dietary antihypertensive agent, but its metabolism and mode of action, which we aimed to investigate with the present study, are not completely understood. Isolated aortic rings from rats were treated ex vivo with oxidants, and rats were infused in vivo with angiotensin-II. Vascular responses to acetylcholine (ACh) and nitrite were assessed by isometric tension recording. The loss of vasodilatory potency in response to oxidants was much more pronounced for ACh as compared to nitrite ex vivo (but not in vivo with angiotensin-II). This effect may be caused by the redox regulation of conversion to xanthine oxidase (XO). Conventionally raised and germ-free mice were treated with nitrite by gavage, which did not improve ACh-mediated vasodilation, but did increase the plasma levels of S-nitros(yl)ated proteins in the conventionally-raised, but not in the germ-free mice. In conclusion, inorganic nitrite represents a dietary drug option to treat arterial hypertension in addition to already established pharmacological treatment. Short-term oxidative stress did not impair the vasodilatory properties of nitrite, which may be beneficial in cardiovascular disease patients. The gastrointestinal microbiome appears to play a key role in nitrite metabolism and bioactivation.
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Affiliation(s)
- Paul Stamm
- Department of Cardiology, Cardiology I, University Medical Center Mainz, 55131 Mainz, Germany; (P.S.); (S.K.); (M.O.); (S.S.); (A.C.); (M.K.)
- German Center for Cardiovascular Research (DZHK), Partner Site Rhine-Main, 55131 Mainz, Germany;
| | - Sanela Kalinovic
- Department of Cardiology, Cardiology I, University Medical Center Mainz, 55131 Mainz, Germany; (P.S.); (S.K.); (M.O.); (S.S.); (A.C.); (M.K.)
| | - Matthias Oelze
- Department of Cardiology, Cardiology I, University Medical Center Mainz, 55131 Mainz, Germany; (P.S.); (S.K.); (M.O.); (S.S.); (A.C.); (M.K.)
| | - Sebastian Steven
- Department of Cardiology, Cardiology I, University Medical Center Mainz, 55131 Mainz, Germany; (P.S.); (S.K.); (M.O.); (S.S.); (A.C.); (M.K.)
- Center for Thrombosis and Hemostasis Mainz, University Medical Center Mainz, 55131 Mainz, Germany;
| | - Alexander Czarnowski
- Department of Cardiology, Cardiology I, University Medical Center Mainz, 55131 Mainz, Germany; (P.S.); (S.K.); (M.O.); (S.S.); (A.C.); (M.K.)
| | - Miroslava Kvandova
- Department of Cardiology, Cardiology I, University Medical Center Mainz, 55131 Mainz, Germany; (P.S.); (S.K.); (M.O.); (S.S.); (A.C.); (M.K.)
| | - Franziska Bayer
- Center for Thrombosis and Hemostasis Mainz, University Medical Center Mainz, 55131 Mainz, Germany;
| | - Christoph Reinhardt
- German Center for Cardiovascular Research (DZHK), Partner Site Rhine-Main, 55131 Mainz, Germany;
- Center for Thrombosis and Hemostasis Mainz, University Medical Center Mainz, 55131 Mainz, Germany;
| | - Thomas Münzel
- Department of Cardiology, Cardiology I, University Medical Center Mainz, 55131 Mainz, Germany; (P.S.); (S.K.); (M.O.); (S.S.); (A.C.); (M.K.)
- German Center for Cardiovascular Research (DZHK), Partner Site Rhine-Main, 55131 Mainz, Germany;
- Correspondence: (T.M.); (A.D.); Tel.: +49-6131-17-6280 (A.D.)
| | - Andreas Daiber
- Department of Cardiology, Cardiology I, University Medical Center Mainz, 55131 Mainz, Germany; (P.S.); (S.K.); (M.O.); (S.S.); (A.C.); (M.K.)
- German Center for Cardiovascular Research (DZHK), Partner Site Rhine-Main, 55131 Mainz, Germany;
- Correspondence: (T.M.); (A.D.); Tel.: +49-6131-17-6280 (A.D.)
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Levonen AL, Laakso J, Vaskonen T, Mervaala E, Karppanen H, Lapatto R. Down-regulation of renal glutathione synthesis by systemic nitric oxide synthesis inhibition in spontaneously hypertensive rats. Biochem Pharmacol 2000; 59:441-3. [PMID: 10644053 DOI: 10.1016/s0006-2952(99)00338-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Nitric oxide stimulates in vitro the synthesis of glutathione, an abundant thiol with a number of functions such as detoxification of xenobiotics and reactive oxygen species. In order to study this relationship in an animal model of hypertension, we treated spontaneously hypertensive rats (SHR) either with a nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) or with a nitric oxide donor isosorbide-5-mononitrate (IS-5-MN). Inhibition of nitric oxide synthesis led to malignant hypertension and to a marked decrease in glutathione synthesis through down-regulation of the rate-limiting enzyme gamma-glutamylcysteine synthetase (GCS). The reduction in GCS activity was further augmented in SHR on a high sodium diet. Renal GCS activity in untreated SHR was 234 +/- 14 and 240 +/- 18 nmol/min/mg protein (mean +/- SD) on a low and high sodium diet, respectively. When L-NAME was included in the diet, the activities dropped to 173 +/- 28 and 123 +/- 28 for the low and high sodium diets, respectively. IS-5-MN attenuated the rise in blood pressure induced by sodium chloride, but did not affect the GCS activity. The mechanism of GCS stimulation by nitric oxide is not known, but our results combined with the literature suggest that a relatively high concentration of nitric oxide is needed.
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Affiliation(s)
- A L Levonen
- Hospital for Children and Adolescents, Helsinki University Central Hospital, Finland.
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