Abstract
Hyperpolarization enhances the intensity of the NMR signals of a molecule, whose in vivo metabolic fate can be monitored by MRI with higher sensitivity. SABRE is a hyperpolarization technique that could potentially be used to image nitric oxide (NO) production in vivo. This would be very important, because NO dysregulation is involved in several pathologies, including cardiovascular ones. The nitric oxide synthase (NOS) pathway leads to NO production via conversion of L-arginine into L-citrulline. NO is a free radical gas with a short half-life in vivo (≈5 s), therefore direct NO quantification is challenging. An indirect method – based on quantifying conversion of an L-Arg- to L-Cit-derivative by 1H NMR spectroscopy – is herein proposed. A small library of pyridyl containing L-Arg derivatives was designed and synthesised. In vitro tests showed that compounds 4a–j and 11a–c were better or equivalent substrates for the eNOS enzyme (NO2 − production = 19–46 μM) than native L-Arg (NO2 − production = 25 μM). Enzymatic conversion of L-Arg to L-Cit derivatives could be monitored by 1H NMR. The maximum hyperpolarization achieved by SABRE reached 870-fold NMR signal enhancement, which opens up exciting future perspectives of using these molecules as hyperpolarized MRI tracers in vivo.
| Original language | English |
|---|---|
| Pages (from-to) | 2730-2742 |
| Number of pages | 13 |
| Journal | Bioorganic & Medicinal Chemistry |
| Volume | 25 |
| Issue number | 10 |
| Early online date | 21 Mar 2017 |
| DOIs | |
| Publication status | Published - 15 May 2017 |
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Keywords
- Animals
- Arginine
- Biocatalysis
- Cattle
- Magnetic Resonance Spectroscopy
- Nitric Oxide
- Nitric Oxide Synthase Type III
- Recombinant Proteins
- Substrate Specificity
- Journal Article
- Hyperpolarization
- L-Arginine
- MRI
- Real-time imaging
- SABRE
Cite this
Synthesis and hyperpolarisation of eNOS substrates for quantification of NO production by (1)H NMR spectroscopy. / Fernandez Diaz-Rullo, Fernando; Zamberlan, Francesco; Mewis, Ryan E.; Fekete, Marianna; Broche, Lionel; Cheyne, Lesley A.; Dall'Angelo, Sergio; Duckett, Simon B.; Dawson, Dana; Zanda, Matteo.
In: Bioorganic & Medicinal Chemistry, Vol. 25, No. 10, 15.05.2017, p. 2730-2742.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Synthesis and hyperpolarisation of eNOS substrates for quantification of NO production by (1)H NMR spectroscopy
AU - Fernandez Diaz-Rullo, Fernando
AU - Zamberlan, Francesco
AU - Mewis, Ryan E.
AU - Fekete, Marianna
AU - Broche, Lionel
AU - Cheyne, Lesley A.
AU - Dall'Angelo, Sergio
AU - Duckett, Simon B.
AU - Dawson, Dana
AU - Zanda, Matteo
N1 - University of Aberdeen’s Development Trust is gratefully acknowledged for a PhD studentship to F.F.D.-R. We thank Dr Serena Montanari for conducting some preliminary experiments. S.B.D. would like to thank the Wellcome Trust (grant and 098335) for funding.
PY - 2017/5/15
Y1 - 2017/5/15
N2 - Hyperpolarization enhances the intensity of the NMR signals of a molecule, whose in vivo metabolic fate can be monitored by MRI with higher sensitivity. SABRE is a hyperpolarization technique that could potentially be used to image nitric oxide (NO) production in vivo. This would be very important, because NO dysregulation is involved in several pathologies, including cardiovascular ones. The nitric oxide synthase (NOS) pathway leads to NO production via conversion of L-arginine into L-citrulline. NO is a free radical gas with a short half-life in vivo (≈5 s), therefore direct NO quantification is challenging. An indirect method – based on quantifying conversion of an L-Arg- to L-Cit-derivative by 1H NMR spectroscopy – is herein proposed. A small library of pyridyl containing L-Arg derivatives was designed and synthesised. In vitro tests showed that compounds 4a–j and 11a–c were better or equivalent substrates for the eNOS enzyme (NO2 − production = 19–46 μM) than native L-Arg (NO2 − production = 25 μM). Enzymatic conversion of L-Arg to L-Cit derivatives could be monitored by 1H NMR. The maximum hyperpolarization achieved by SABRE reached 870-fold NMR signal enhancement, which opens up exciting future perspectives of using these molecules as hyperpolarized MRI tracers in vivo.
AB - Hyperpolarization enhances the intensity of the NMR signals of a molecule, whose in vivo metabolic fate can be monitored by MRI with higher sensitivity. SABRE is a hyperpolarization technique that could potentially be used to image nitric oxide (NO) production in vivo. This would be very important, because NO dysregulation is involved in several pathologies, including cardiovascular ones. The nitric oxide synthase (NOS) pathway leads to NO production via conversion of L-arginine into L-citrulline. NO is a free radical gas with a short half-life in vivo (≈5 s), therefore direct NO quantification is challenging. An indirect method – based on quantifying conversion of an L-Arg- to L-Cit-derivative by 1H NMR spectroscopy – is herein proposed. A small library of pyridyl containing L-Arg derivatives was designed and synthesised. In vitro tests showed that compounds 4a–j and 11a–c were better or equivalent substrates for the eNOS enzyme (NO2 − production = 19–46 μM) than native L-Arg (NO2 − production = 25 μM). Enzymatic conversion of L-Arg to L-Cit derivatives could be monitored by 1H NMR. The maximum hyperpolarization achieved by SABRE reached 870-fold NMR signal enhancement, which opens up exciting future perspectives of using these molecules as hyperpolarized MRI tracers in vivo.
KW - Animals
KW - Arginine
KW - Biocatalysis
KW - Cattle
KW - Magnetic Resonance Spectroscopy
KW - Nitric Oxide
KW - Nitric Oxide Synthase Type III
KW - Recombinant Proteins
KW - Substrate Specificity
KW - Journal Article
KW - Hyperpolarization
KW - L-Arginine
KW - MRI
KW - Real-time imaging
KW - SABRE
UR - http://www.scopus.com/inward/record.url?scp=85016646550&partnerID=8YFLogxK
U2 - 10.1016/j.bmc.2017.03.041
DO - 10.1016/j.bmc.2017.03.041
M3 - Article
VL - 25
SP - 2730
EP - 2742
JO - Bioorganic & Medicinal Chemistry
JF - Bioorganic & Medicinal Chemistry
SN - 0968-0896
IS - 10
ER -