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A Bartolini - One of the best experts on this subject based on the ideXlab platform.
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Pro-cognitive activity induced in the rat by low doses of R-(+)-Hyoscyamine.
Fitoterapia, 2000Co-Authors: Carla Ghelardini, N Galeotti, A BartoliniAbstract:In the passive-avoidance test R-(+)-Hyoscyamine (10-100 microg kg(-1) i.p.) prevented amnesia induced by antimuscarinic treatment with AF-64A and benzhexol. The antiamnesic effect of R-(+)-Hyoscyamine was comparable to that exerted by the cholinesterase inhibitor physostigmine (0.2 mg kg(-1) i.p) and the M(1) selective agonist AF-102B (10 mg kg(-1) i.p.). In the social learning test, R-(+)-Hyoscyamine (10-100 microg kg(-1) i.p.) in adults rats, reduced the duration of active exploration of the familiar partner in the second session of the test similar to the nootropic drug piracetam (30 mg kg(-1) i.p.). These results demonstrated the ability of R-(+)-Hyoscyamine to modulate memory functions and suggest that R-(+)-Hyoscyamine could be useful in the treatment of cognitive deficits.
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stereoselective increase in cholinergic transmission by r Hyoscyamine
Neuropharmacology, 1997Co-Authors: Carla Ghelardini, Fulvio Gualtieri, Piero Angeli, Giancarlo Pepeu, Fiorella Casamenti, Alberto Giotti, Novella M Romanelli, Grazia M Giovannini, P Malmbergaiello, A BartoliniAbstract:Abstract R-(+)-Hyoscyamine, the dextro enantiomer of atropine, has been shown to amplify cholinergic transmission. R-(+)-Hyoscyamine, unlike S-(—)-Hyoscyamine, was able to increase acetylcholine release both in vitro and in vivo at a range of concentrations (10−14 to 10−12 M) and doses (5 μg/kg i.p.) which were inadequate for blocking muscarinic receptors. The increase over control values in ACh release was 15.9 ± 2.1% in in vitro experiments performed in rat phrenic nerve-hemidiaphragm preparations (n = 6), and 63.3 + 16.3% in cortical microdialysis performed in free-moving rats (n = 5). The maximum ACh release was reached 60 min after R-(+)-Hyoscyamine administration in in vivo experiments. At the same doses and concentrations, R-(+)-Hyoscyamine was also able to elicit: antinociception of a cholinergic type (55.6–112.7% depending on the test used); complete prevention of scopolamine- and dicyclomine-induced amnesia; potentiation of muscular contractions electrically evoked in isolated guinea-pig ileum (16.7 ± 3.6%) and in rat phrenic nerve-hemidiaphragm (19.9 ± 3.2%) preparations. Antinociception was performed using the hot-plate and acetic acid abdominal constriction tests in mice, and the paw pressure test in rats, while prevention of induced amnesia was evaluated in mice using the passive-avoidance test. The respective affinities (pA2) for R-(+)- and S-(—)-Hyoscyamine vs M1 (rabbit vas deferens), M2 (rat atrium) and M3 (rat ileum) receptor subtypes were as follows: 7.05 ± 0.05/9.33 ± 0.03 for M1; 7.25 ± 0.04/8.95 ± 0.01 for M2; 6.88 ± 0.05/9.04 ± 0.03 for M3. The respective pKi values for R-(+)- and S-(—)-Hyoscyamine vs the five human muscarinic receptor subtypes expressed in Chinese hamster oocytes (CHO-K1) were as follows: 8.21 ± 0.07/9.48 ± 0.18 for m1; 7.89 ± 0.06/9.45 ± 0.31 for m2; 8.06 ± 0.18/9.30 ± 0.19 for m3; 8.35 ± 0.11/9.55 ± 0.13 for m4; 8.17 ± 0.08/9.24 ± 0.30 for m5. © 1997 Elsevier Science Ltd. All rights reserved.
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Stereoselective Increase in Cholinergic Transmission by R-(+)-Hyoscyamine
Neuropharmacology, 1997Co-Authors: Carla Ghelardini, Fulvio Gualtieri, M. Novella Romanelli, Piero Angeli, Giancarlo Pepeu, M. Grazia Giovannini, Fiorella Casamenti, Petra Malmberg-aiello, Alberto Giotti, A BartoliniAbstract:Abstract R-(+)-Hyoscyamine, the dextro enantiomer of atropine, has been shown to amplify cholinergic transmission. R-(+)-Hyoscyamine, unlike S-(—)-Hyoscyamine, was able to increase acetylcholine release both in vitro and in vivo at a range of concentrations (10−14 to 10−12 M) and doses (5 μg/kg i.p.) which were inadequate for blocking muscarinic receptors. The increase over control values in ACh release was 15.9 ± 2.1% in in vitro experiments performed in rat phrenic nerve-hemidiaphragm preparations (n = 6), and 63.3 + 16.3% in cortical microdialysis performed in free-moving rats (n = 5). The maximum ACh release was reached 60 min after R-(+)-Hyoscyamine administration in in vivo experiments. At the same doses and concentrations, R-(+)-Hyoscyamine was also able to elicit: antinociception of a cholinergic type (55.6–112.7% depending on the test used); complete prevention of scopolamine- and dicyclomine-induced amnesia; potentiation of muscular contractions electrically evoked in isolated guinea-pig ileum (16.7 ± 3.6%) and in rat phrenic nerve-hemidiaphragm (19.9 ± 3.2%) preparations. Antinociception was performed using the hot-plate and acetic acid abdominal constriction tests in mice, and the paw pressure test in rats, while prevention of induced amnesia was evaluated in mice using the passive-avoidance test. The respective affinities (pA2) for R-(+)- and S-(—)-Hyoscyamine vs M1 (rabbit vas deferens), M2 (rat atrium) and M3 (rat ileum) receptor subtypes were as follows: 7.05 ± 0.05/9.33 ± 0.03 for M1; 7.25 ± 0.04/8.95 ± 0.01 for M2; 6.88 ± 0.05/9.04 ± 0.03 for M3. The respective pKi values for R-(+)- and S-(—)-Hyoscyamine vs the five human muscarinic receptor subtypes expressed in Chinese hamster oocytes (CHO-K1) were as follows: 8.21 ± 0.07/9.48 ± 0.18 for m1; 7.89 ± 0.06/9.45 ± 0.31 for m2; 8.06 ± 0.18/9.30 ± 0.19 for m3; 8.35 ± 0.11/9.55 ± 0.13 for m4; 8.17 ± 0.08/9.24 ± 0.30 for m5. © 1997 Elsevier Science Ltd. All rights reserved.
Myungsuk Choi - One of the best experts on this subject based on the ideXlab platform.
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production of tropane alkaloids during de differentiation of scopolia parviflora calli
Journal of Natural Products, 2010Co-Authors: Seung Mi Kang, Won Kyun Choi, Mi Jin Jeong, C. S. Karigar, Myungsuk ChoiAbstract:The production of tropane alkaloids during differentiation and de-differentiation of Scopolia parviflora calli was studied. Tropane alkaloid production drastically decreased during calli de-differentiation. Scopolamine (1) production decreased after 10 days of culture, whereas that of Hyoscyamine (2) decreased during de-differentiation of root to calli. The production of 1 was enhanced in calli undergoing differentiation to shoot after 60 days of culture, reaching a maximum by 80 days. However, production of Hyoscyamine in regenerated plants was lower. The expression level of Hyoscyamine 6β-hydroxylase (H6H), a key biosynthetic enzyme for tropane alkaloids, was significantly increased in 4-week-old calli. This study suggests that the biosynthesis of tropane alkaloids is regulated inversely in de-differentiating Scopolia parviflora calli.
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Production of tropane alkaloids during de-differentiation of Scopolia parviflora calli.
Journal of natural products, 2010Co-Authors: Yong Duck Kim, Seung Mi Kang, Won Kyun Choi, Mi Jin Jeong, C. S. Karigar, Ji Yun Min, Myungsuk ChoiAbstract:The production of tropane alkaloids during differentiation and de-differentiation of Scopolia parviflora calli was studied. Tropane alkaloid production drastically decreased during calli de-differentiation. Scopolamine (1) production decreased after 10 days of culture, whereas that of Hyoscyamine (2) decreased during de-differentiation of root to calli. The production of 1 was enhanced in calli undergoing differentiation to shoot after 60 days of culture, reaching a maximum by 80 days. However, production of Hyoscyamine in regenerated plants was lower. The expression level of Hyoscyamine 6beta-hydroxylase (H6H), a key biosynthetic enzyme for tropane alkaloids, was significantly increased in 4-week-old calli. This study suggests that the biosynthesis of tropane alkaloids is regulated inversely in de-differentiating Scopolia parviflora calli.
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growth pattern and content of tropane alkaloids of metabolic engineered scopolia parviflora hairy root lines
The Korean Journal of Medicinal Crop Science, 2004Co-Authors: Youngmin Kang, Myungsuk ChoiAbstract:Hyoscyamine and scopolamine are two most common tropane alkaloids found in the Solanaceae. The pEB expression vector carrying Nspmt gene was transformed to Agrobacterium rhizogenes. The growth of transgenic hairy roots were approximately to 80% of the wild type root. Transgenic hairy roots are less developed on only their branch roots than those of the wild type root. The extracts from Nspmt transgenic hairy root lines, 3 and 5 contained between 3.52 and 4.23 mg/g dry weight as Hyoscyamine and did between 5.23 to 6.40 mg/g dry weight as scopolamine. These results showed that the overexpression of the pmt gene enhanced tropane alkaloids production of S. parviflora transformed roots and this improvement affected both Hyoscyamine and scopolamine production.
Carla Ghelardini - One of the best experts on this subject based on the ideXlab platform.
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Pro-cognitive activity induced in the rat by low doses of R-(+)-Hyoscyamine.
Fitoterapia, 2000Co-Authors: Carla Ghelardini, N Galeotti, A BartoliniAbstract:In the passive-avoidance test R-(+)-Hyoscyamine (10-100 microg kg(-1) i.p.) prevented amnesia induced by antimuscarinic treatment with AF-64A and benzhexol. The antiamnesic effect of R-(+)-Hyoscyamine was comparable to that exerted by the cholinesterase inhibitor physostigmine (0.2 mg kg(-1) i.p) and the M(1) selective agonist AF-102B (10 mg kg(-1) i.p.). In the social learning test, R-(+)-Hyoscyamine (10-100 microg kg(-1) i.p.) in adults rats, reduced the duration of active exploration of the familiar partner in the second session of the test similar to the nootropic drug piracetam (30 mg kg(-1) i.p.). These results demonstrated the ability of R-(+)-Hyoscyamine to modulate memory functions and suggest that R-(+)-Hyoscyamine could be useful in the treatment of cognitive deficits.
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Antinociceptive effect of R-(+)-Hyoscyamine on the conjunctival reflex test in rabbits.
The Japanese Journal of Pharmacology, 1999Co-Authors: Carla Ghelardini, Nicoletta Galeotti, L. Fantetti, Fulvio Gualtieri, Serena Scapecchi, Alessandro BartoliniAbstract:R-(+)-Hyoscyamine (1-10 microg/kg, s.c.) dose-dependently increased the local anesthetic effect of procaine (50 microg/ml) and lidocaine (50 microg/ml) in the conjunctival reflex test in the rabbit. This potentiating effect is completely prevented by the M1 antagonist dicyclomine (10 mg/kg, s.c.). The intensity of R-(+)-Hyoscyamine antinociception was comparable to that induced by morphine (2 mg/kg, s.c.) and minaprine (15 mg/kg, s.c.), used as analgesic reference drugs. In the same experimental conditions, the S-(-)-enantiomer of atropine (0.1-10 microg/kg, s.c.), was completely ineffective. The present results confirm the ability of R-(+)-Hyoscyamine to produce a paradoxical antinociceptive effect mediated by a cholinergic mechanism not only in rodents but also in the rabbit.
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stereoselective increase in cholinergic transmission by r Hyoscyamine
Neuropharmacology, 1997Co-Authors: Carla Ghelardini, Fulvio Gualtieri, Piero Angeli, Giancarlo Pepeu, Fiorella Casamenti, Alberto Giotti, Novella M Romanelli, Grazia M Giovannini, P Malmbergaiello, A BartoliniAbstract:Abstract R-(+)-Hyoscyamine, the dextro enantiomer of atropine, has been shown to amplify cholinergic transmission. R-(+)-Hyoscyamine, unlike S-(—)-Hyoscyamine, was able to increase acetylcholine release both in vitro and in vivo at a range of concentrations (10−14 to 10−12 M) and doses (5 μg/kg i.p.) which were inadequate for blocking muscarinic receptors. The increase over control values in ACh release was 15.9 ± 2.1% in in vitro experiments performed in rat phrenic nerve-hemidiaphragm preparations (n = 6), and 63.3 + 16.3% in cortical microdialysis performed in free-moving rats (n = 5). The maximum ACh release was reached 60 min after R-(+)-Hyoscyamine administration in in vivo experiments. At the same doses and concentrations, R-(+)-Hyoscyamine was also able to elicit: antinociception of a cholinergic type (55.6–112.7% depending on the test used); complete prevention of scopolamine- and dicyclomine-induced amnesia; potentiation of muscular contractions electrically evoked in isolated guinea-pig ileum (16.7 ± 3.6%) and in rat phrenic nerve-hemidiaphragm (19.9 ± 3.2%) preparations. Antinociception was performed using the hot-plate and acetic acid abdominal constriction tests in mice, and the paw pressure test in rats, while prevention of induced amnesia was evaluated in mice using the passive-avoidance test. The respective affinities (pA2) for R-(+)- and S-(—)-Hyoscyamine vs M1 (rabbit vas deferens), M2 (rat atrium) and M3 (rat ileum) receptor subtypes were as follows: 7.05 ± 0.05/9.33 ± 0.03 for M1; 7.25 ± 0.04/8.95 ± 0.01 for M2; 6.88 ± 0.05/9.04 ± 0.03 for M3. The respective pKi values for R-(+)- and S-(—)-Hyoscyamine vs the five human muscarinic receptor subtypes expressed in Chinese hamster oocytes (CHO-K1) were as follows: 8.21 ± 0.07/9.48 ± 0.18 for m1; 7.89 ± 0.06/9.45 ± 0.31 for m2; 8.06 ± 0.18/9.30 ± 0.19 for m3; 8.35 ± 0.11/9.55 ± 0.13 for m4; 8.17 ± 0.08/9.24 ± 0.30 for m5. © 1997 Elsevier Science Ltd. All rights reserved.
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Stereoselective Increase in Cholinergic Transmission by R-(+)-Hyoscyamine
Neuropharmacology, 1997Co-Authors: Carla Ghelardini, Fulvio Gualtieri, M. Novella Romanelli, Piero Angeli, Giancarlo Pepeu, M. Grazia Giovannini, Fiorella Casamenti, Petra Malmberg-aiello, Alberto Giotti, A BartoliniAbstract:Abstract R-(+)-Hyoscyamine, the dextro enantiomer of atropine, has been shown to amplify cholinergic transmission. R-(+)-Hyoscyamine, unlike S-(—)-Hyoscyamine, was able to increase acetylcholine release both in vitro and in vivo at a range of concentrations (10−14 to 10−12 M) and doses (5 μg/kg i.p.) which were inadequate for blocking muscarinic receptors. The increase over control values in ACh release was 15.9 ± 2.1% in in vitro experiments performed in rat phrenic nerve-hemidiaphragm preparations (n = 6), and 63.3 + 16.3% in cortical microdialysis performed in free-moving rats (n = 5). The maximum ACh release was reached 60 min after R-(+)-Hyoscyamine administration in in vivo experiments. At the same doses and concentrations, R-(+)-Hyoscyamine was also able to elicit: antinociception of a cholinergic type (55.6–112.7% depending on the test used); complete prevention of scopolamine- and dicyclomine-induced amnesia; potentiation of muscular contractions electrically evoked in isolated guinea-pig ileum (16.7 ± 3.6%) and in rat phrenic nerve-hemidiaphragm (19.9 ± 3.2%) preparations. Antinociception was performed using the hot-plate and acetic acid abdominal constriction tests in mice, and the paw pressure test in rats, while prevention of induced amnesia was evaluated in mice using the passive-avoidance test. The respective affinities (pA2) for R-(+)- and S-(—)-Hyoscyamine vs M1 (rabbit vas deferens), M2 (rat atrium) and M3 (rat ileum) receptor subtypes were as follows: 7.05 ± 0.05/9.33 ± 0.03 for M1; 7.25 ± 0.04/8.95 ± 0.01 for M2; 6.88 ± 0.05/9.04 ± 0.03 for M3. The respective pKi values for R-(+)- and S-(—)-Hyoscyamine vs the five human muscarinic receptor subtypes expressed in Chinese hamster oocytes (CHO-K1) were as follows: 8.21 ± 0.07/9.48 ± 0.18 for m1; 7.89 ± 0.06/9.45 ± 0.31 for m2; 8.06 ± 0.18/9.30 ± 0.19 for m3; 8.35 ± 0.11/9.55 ± 0.13 for m4; 8.17 ± 0.08/9.24 ± 0.30 for m5. © 1997 Elsevier Science Ltd. All rights reserved.
Seung Mi Kang - One of the best experts on this subject based on the ideXlab platform.
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production of tropane alkaloids during de differentiation of scopolia parviflora calli
Journal of Natural Products, 2010Co-Authors: Seung Mi Kang, Won Kyun Choi, Mi Jin Jeong, C. S. Karigar, Myungsuk ChoiAbstract:The production of tropane alkaloids during differentiation and de-differentiation of Scopolia parviflora calli was studied. Tropane alkaloid production drastically decreased during calli de-differentiation. Scopolamine (1) production decreased after 10 days of culture, whereas that of Hyoscyamine (2) decreased during de-differentiation of root to calli. The production of 1 was enhanced in calli undergoing differentiation to shoot after 60 days of culture, reaching a maximum by 80 days. However, production of Hyoscyamine in regenerated plants was lower. The expression level of Hyoscyamine 6β-hydroxylase (H6H), a key biosynthetic enzyme for tropane alkaloids, was significantly increased in 4-week-old calli. This study suggests that the biosynthesis of tropane alkaloids is regulated inversely in de-differentiating Scopolia parviflora calli.
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Production of tropane alkaloids during de-differentiation of Scopolia parviflora calli.
Journal of natural products, 2010Co-Authors: Yong Duck Kim, Seung Mi Kang, Won Kyun Choi, Mi Jin Jeong, C. S. Karigar, Ji Yun Min, Myungsuk ChoiAbstract:The production of tropane alkaloids during differentiation and de-differentiation of Scopolia parviflora calli was studied. Tropane alkaloid production drastically decreased during calli de-differentiation. Scopolamine (1) production decreased after 10 days of culture, whereas that of Hyoscyamine (2) decreased during de-differentiation of root to calli. The production of 1 was enhanced in calli undergoing differentiation to shoot after 60 days of culture, reaching a maximum by 80 days. However, production of Hyoscyamine in regenerated plants was lower. The expression level of Hyoscyamine 6beta-hydroxylase (H6H), a key biosynthetic enzyme for tropane alkaloids, was significantly increased in 4-week-old calli. This study suggests that the biosynthesis of tropane alkaloids is regulated inversely in de-differentiating Scopolia parviflora calli.
Angela Schaal - One of the best experts on this subject based on the ideXlab platform.
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Tropinone reduction in Atropa belladonna root cultures
Phytochemistry, 1994Co-Authors: Birgit Dräger, Angela SchaalAbstract:Abstract Transformed root cultures of Atropa belladonna accumulate the tropane alkaloid Hyoscyamine and the precursors tropane-3α-ol (tropine) and tropane-3β-ol (pseudotropine), depending on the culture stage. The latter are stereoisomeric reduction products of tropinone and are formed by two different NADPH-dependent tropinone reductases. Feeding experiments indicate that tropine and pseudotropine do not isomerize and that only tropine is incorporated into hyocyamine. The pseudotropine-forming tropinone reductase was purified, characterized and compared with other tropinone reductases reported so far. It has a molecular weight of 78 500, three identical subunits measured as 27 500 by SDS-PAGE, an IEP at pH 4.5, and a pH optimum at 6.25. The enzyme has a Km of 90,μM for tropinone and 21 μM for NADPH. It catalyses the reduction of a limited number of analogues of tropinone, but with higher Km values. None of the substrate analogues inhibited tropinone reduction. The regulatory role of the pseudotropine-forming tropinone reductase in tropane alkaloid metabolism is discussed.