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Watcharin Nuankaew - One of the best experts on this subject based on the ideXlab platform.
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Effect of Mitragyna speciosa aqueous extract on ethanol withdrawal symptoms in mice.
Fitoterapia, 2007Co-Authors: Ekkasit Kumarnsit, Niwat Keawpradub, Watcharin NuankaewAbstract:Administration of the aqueous extract of Mitragyna speciosa at a dose of 300 mg/kg significantly inhibited ethanol withdrawal-induced behaviors that included rearing, displacement and head weaving. The results also showed that at doses of 100, 300 and 500 mg/kg M. speciosa showed antidepressant activity without effect on the spontaneous motor activity.
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acute and long term effects of alkaloid extract of Mitragyna speciosa on food and water intake and body weight in rats
Fitoterapia, 2006Co-Authors: Ekkasit Kumarnsit, Niwat Keawpradub, Watcharin NuankaewAbstract:Acute administration of Mitragyna speciosa (MS) extract (45 and 50 mg/kg) significantly resulted in dose-dependent decreases in food and water intakes (P<0.05) in rats. Prolonged suppressing effects were observed following administration of the MS extract (40 mg/kg) for 60 consecutive days. Moreover, the long-term administration also significantly suppressed weight gaining.
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Acute and long-term effects of alkaloid extract of Mitragyna speciosa on food and water intake and body weight in rats.
Fitoterapia, 2006Co-Authors: Ekkasit Kumarnsit, Niwat Keawpradub, Watcharin NuankaewAbstract:Acute administration of Mitragyna speciosa (MS) extract (45 and 50 mg/kg) significantly resulted in dose-dependent decreases in food and water intakes (P
Hiromitsu Takayama - One of the best experts on this subject based on the ideXlab platform.
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The cellular toxicology of mitragynine, the dominant alkaloid of the narcotic-like herb, Mitragyna speciosa Korth
Toxicology Research, 2015Co-Authors: Nor Aini Saidin, Hiromitsu Takayama, Elaine Holmes, Nigel J. GooderhamAbstract:Mitragyna speciosa Korth (Kratom), a herb of the Rubiaceae family is indigenous to southeast Asia. The plant and its dominant alkaloid mitragynine (MIT) are narcotic/analgesic and illicit consumption is widespread in Asia; the toxicological consequences of consumption are poorly documented. We determined cytotoxicity of MIT on human cell lines and report dose and time-dependent stimulation and inhibition of proliferation. Since MIT has powerful opiate-like activity, we focussed on human neuronal SH-SY5Y cell line and found the colony forming ability of cells treated with MIT showed a dose-dependent trend for reduced survival. Studies using metabolically competent MCL-5 cells and chemical inhibitors indicated that CYP 2E1 and 2A6 were involved in the cytotoxicity. Cytotoxicity was preceded by cell cycle arrest mainly at G1 and S phase. To assess whether arrest was due to DNA damage or mutation, we examined genotoxic potential using the L5178 TK+/− mouse lymphoma assay and found that MIT was not genotoxic at the TK locus, even at doses that were highly cytotoxic. To investigate mechanisms of MIT cytotoxicity, we used flow cytometry and annexin V with 7-amino-actinomycin D staining and show apoptosis and necrotic activity. Apoptosis was further supported as MIT rapidly induced the activity of executioner caspases 3/7. However, cytotoxicity of MIT was partially reduced by inclusion of the opioid receptor antagonist naloxone, a μ and δ opioid receptor antagonist, suggesting that cytotoxicity depends in part on opioid signalling, consistent with the known toxicity of other opiates. Based on consumption of 20 leaves per day of Mitragyna speciosa, we estimated daily human exposure to MIT to be about 17 mg MIT for regular consumers, potentially giving plasma concentrations in of 10−9 to 10−7 M. Importantly, fatalities after kratom consumption have been reported to occur in individuals with blood mitragynine concentrations of between 0.45–1.0 μM, substantially lower than the threshold of toxicity predicted from this in vitro report. Clearly the implications of these findings to humans consuming Mitragyna speciosa leaves will require further study, but individuals taking large quantities of these opiate-like materials may be at risk, especially those who have a high CYP2E1 activity, such as heavy alcohol users.
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New heteroyohimbine-type oxindole alkaloid from the leaves of Thai Mitragyna hirsuta
Journal of Natural Medicines, 2007Co-Authors: Mariko Kitajima, Terumi Nakayama, Noriyuki Kogure, Sumphan Wongseripipatana, Hiromitsu TakayamaAbstract:A new oxindole alkaloid, isomitraphyllinol ( 1 ), was isolated from the leaves of Thai Mitragyna hirsuta , together with five known oxindole alkaloids ( 2 – 6 ). The structure of the new compound was determined by spectroscopic analysis.
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A new indole alkaloid, 7-hydroxyspeciociliatine, from the fruits of Malaysian Mitragyna speciosa and its opioid agonistic activity
Journal of Natural Medicines, 2006Co-Authors: Mariko Kitajima, Ikram M. Said, Noriyuki Kogure, Kaori Misawa, Syunji Horie, Yoshio Hatori, Toshihiko Murayama, Hiromitsu TakayamaAbstract:A new indole alkaloid, 7-hydroxyspeciociliatine ( 1 ), was isolated from the fruits of Malaysian Mitragyna speciosa Korth., together with 11 known indole and oxindole alkaloids ( 3 – 13 ). The structure of the new compound was determined by spectroscopic analysis and chemical conversion. The opioid agonistic activity of the new alkaloid was investigated in guinea-pig ileum experiments. The compound was found to have a weak stimulatory effect on μ-opioid receptors.
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A New 9-Methoxyyohimbine-Type Indole Alkaloid from Mitragyna africanus
Chemical & pharmaceutical bulletin, 2004Co-Authors: Hiromitsu Takayama, Mariko Kitajima, Norio Aimi, Hayato Ishikawa, Muhammad AjiAbstract:A new yohimbine-type indole alkaloid (1) was isolated from the stem bark of Mitragyna africanus (WILLD.) collected in Nigeria, along with known seven Corynanthe-type oxindole alkaloids, two secoiridoids, three lignans, and a quinovic acid derivative. Their structures were elucidated by spectroscopic analyses.
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Structure revision of Mitragynaline, an indole alkaloid in Mitragyna speciosa
Tetrahedron Letters, 2001Co-Authors: Hiromitsu Takayama, Mariko Kitajima, Norio Aimi, Shin-ichiro Sakai, Hayato Ishikawa, Mika Kurihara, Ikram M. Said, Hiroko Seki, Kentaro Yamaguchi, Peter J. HoughtonAbstract:Abstract The structure of Mitragynaline, an indole alkaloid isolated from Malaysian Mitragyna speciosa , was revised as formula 3 by analysis of the NMR spectra measured at low temperature and by chemical transformation with DDQ oxidation from the known alkaloid mitragynine ( 5 ).
Sharif Mahsufi Mansor - One of the best experts on this subject based on the ideXlab platform.
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Metabolomics data of Mitragyna speciosa leaf using LC-ESI-TOF-MS
Elsevier, 2018Co-Authors: Rubashiny Veeramohan, Sharif Mahsufi Mansor, Kamalrul Azlan Azizan, Wan Mohd Aizat, Hoe-han Goh, Nur Sabrina Mohd Yusof, Syarul Nataqain BaharumAbstract:Mitragyna speciosa is a psychoactive plant known as “ketum” in Malaysia and “kratom” in Thailand. This plant is distinctly known to produce two important alkaloids, namely mitragynine (MG) and 7-hydroxymitragynine (7-OH-MG) that can bind to opioid receptors [1]. MG was reported to exhibit antidepressant properties in animal studies [2]. These compounds were also proposed to have the potential to replace opioid analgesics with much lower risks of side effects [3]. To date, there are only over 40 metabolites identified in M. speciosa [4,5]. To obtain a more complete profile of secondary metabolites in ketum, we performed metabolomics study using mature leaves of the green M. speciosa variety. The leaf samples were extracted using methanol prior to liquid chromatography-electrospray ionization-time of flight-mass spectrometry (LC-ESI-TOF-MS) analysis. This data can be useful to for the identification of unknown metabolites that are associated with alkaloid biosynthesis pathway in M. speciosa. Keywords: Alkaloids, LC–MS, Metabolomics, Methanolic extraction, Mitragyna specios
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discriminative stimulus properties of mitragynine kratom in rats
Psychopharmacology, 2015Co-Authors: Norsyifa Harun, Sharif Mahsufi Mansor, Zurina Hassan, V Navaratnam, Mohammed ShoaibAbstract:Rationale Mitragynine (MG) is the primary active alkaloid extracted from the leaves of Mitragyna speciosa or kratom and exhibits pharmacological activities mediated by opioid receptors. The plant has been traditionally used for its opium and psychostimulant-like effects to increase work efficiency or as a substitute in the self-treatment of opiate addiction.
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Subchronic exposure to mitragynine, the principal alkaloid of Mitragyna speciosa, in rats.
Journal of ethnopharmacology, 2013Co-Authors: Azadeh Sabetghadam, Surash Ramanathan, Sreenivasan Sasidharan, Sharif Mahsufi MansorAbstract:Abstract Ethnopharmacological relevance Mitragyna speciosa is a popular medicinal plant in Southeast Asia which is commonly used for its morphine-like effects. Although the analgesic properties of Mitragyna speciosa and its ability to ameliorate withdrawal signs after abrupt cessation of opioid abuse are well known, information about the long-term safety of the plant's active compounds is lacking. In this work, we evaluated the effects of sub-chronic exposure to mitragynine, the principal alkaloid of Mitragyna speciosa leaves in rats. Materials and methods: Male and female Sprague-Dawley rats received three doses of mitragynine (1, 10, 100 mg/kg, p.o) for 28 days respectively. Food intake and relative body weight were measured during the experiment. After completion of drug treatment biochemical, hematological, and histological analyses were performed. Results No mortality was observed in any of the treatment groups. The groups of rats treated with the lower and intermediate doses showed no toxic effects during the study. However, the relative body weight of the group of female rats treated with the 100 mg/kg dose was decreased significantly. Food intake also tended to decrease in the same group. Only relative liver weight increased after treatment with the high dose of mitragynine (100 mg/ kg) in both the male and female treatment groups of rats. Biochemical and hematological parameters were also altered especially in high dose treatment group which corresponds to the histopathological changes. Conclusions The study demonstrated that mitragynine is relatively safe at lower sub-chronic doses (1–10 mg/kg) but exhibited toxicity at a highest dose (sub-chronic 28 days: 100 mg/kg). This was confirmed by liver, kidney, and brain histopathological changes, as well as hematological and biochemical changes.
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in vitro effect of mitragynine on activity of drug metabolizing enzymes n demethylase and glutathione s transferase in streptozotocin induced diabetic rats
2012Co-Authors: Rukhsana Anwar, Abas Hj Hussin, Sabariah Ismail, Sharif Mahsufi MansorAbstract:Mitragynine is the major alkaloid of Mitragyna speciosa Korth. It is responsible for antinociceptive, antidepressant like effects and used as substitute for morphine to treat opium withdrawal. Mitragyna speciosa plant belongs to Rubiaceae family. In Malaysia, the leaves of Mitragyna speciosa are used to treat diarrhea, pain and as cough suppressant. Following experiments were undertaken to evaluate the effect of mitragynine on aminopyrine N-demethylase and glutathione S-transferase activity in diabetic Sprague-Dawley (SD) male and female rats. Different concentrations of mitragynine (0.0025µM-250µM) were used to evaluate activity of both enzymes. Collagenase perfusion technique was used to isolate hepatocytes and aminopyrine Ndemethylase activity was determined in hepatocytes by measuring the quantity of formaldehyde formed. Rat livers were taken out and cytosolic fraction was prepared. GST activity was measured in cytosolic fraction by kinetics of thioether product formation over time. Results showed that in diabetic male and female SD rat hepatocytes, a significant (p< 0.05) increase in aminopyrine N-demethylase activity was observed only with 250µM mitragynine. For phase II drug metabolizing enzyme, mitragynine (0.25µM -250µM) significantly (p<0.05) inhibited the GST specific activity in both diabetic male and female rats. In conclusion this study indicates that the aminopyrine N-demethylase enzyme induction and GST activity inhibition by mitragynine is not influenced by sex. Aminopyrine N-demethylase activity increases only on high concentration of mitragynine and lower concentrations cannot be able to change it. However GST activity inhibition is dosedependent.
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IN VITRO EFFECT OF MITRAGYNINE (A MAJOR ALKALOID OF Mitragyna SPECIOSA KORTH) ON AMINOPYRINE METABOLISM IN RAT HEPATOCYTES
2012Co-Authors: Rukhsana Anwar, Abas Hj Hussin, Sabariah Ismail, Sharif Mahsufi Mansor, Pulau PenangAbstract:Mitragyna speciosa Korth. is a member of the Rubiaceae family. More than 25 alkaloids have been isolated from Mitragyna speciosa. Mitragynine is the major alkaloid of this plant and is responsible for antinociceptive action. No single study is available about the effect of mitragynine on aminopyrine Ndemethylase activity in rat hepatocytes. Experiments were undertaken to evaluate the effect of mitragynine in different age groups (adult & old) of Sprague- Dawley (SD) male and female rat hepatocytes. In vitro this evaluation was assessed by different concentration of mitragynine (0.0025µM-250µM). Hepatocytes were prepared by collagenase perfusion technique. Aminopyrine N-demethylase activity was determined by measuring the quantity of formaldehyde formed. Results showed that a significant increase in aminopyrine N-demethylase activity was observed in the adult male, female and old female SD rat hepatocytes treated with 250µM mitragynine (p< 0.05). However, the old male rat did not show any significant change at any concentration of mitragynine. In conclusion this study indicates the induction of hepatic drug metabolizing enzymes by mitragynine is affected by the aging process in male but unaffected in female.
Ekkasit Kumarnsit - One of the best experts on this subject based on the ideXlab platform.
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Effect of Mitragyna speciosa aqueous extract on ethanol withdrawal symptoms in mice.
Fitoterapia, 2007Co-Authors: Ekkasit Kumarnsit, Niwat Keawpradub, Watcharin NuankaewAbstract:Administration of the aqueous extract of Mitragyna speciosa at a dose of 300 mg/kg significantly inhibited ethanol withdrawal-induced behaviors that included rearing, displacement and head weaving. The results also showed that at doses of 100, 300 and 500 mg/kg M. speciosa showed antidepressant activity without effect on the spontaneous motor activity.
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acute and long term effects of alkaloid extract of Mitragyna speciosa on food and water intake and body weight in rats
Fitoterapia, 2006Co-Authors: Ekkasit Kumarnsit, Niwat Keawpradub, Watcharin NuankaewAbstract:Acute administration of Mitragyna speciosa (MS) extract (45 and 50 mg/kg) significantly resulted in dose-dependent decreases in food and water intakes (P<0.05) in rats. Prolonged suppressing effects were observed following administration of the MS extract (40 mg/kg) for 60 consecutive days. Moreover, the long-term administration also significantly suppressed weight gaining.
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Acute and long-term effects of alkaloid extract of Mitragyna speciosa on food and water intake and body weight in rats.
Fitoterapia, 2006Co-Authors: Ekkasit Kumarnsit, Niwat Keawpradub, Watcharin NuankaewAbstract:Acute administration of Mitragyna speciosa (MS) extract (45 and 50 mg/kg) significantly resulted in dose-dependent decreases in food and water intakes (P
Norio Aimi - One of the best experts on this subject based on the ideXlab platform.
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A New 9-Methoxyyohimbine-Type Indole Alkaloid from Mitragyna africanus
Chemical & pharmaceutical bulletin, 2004Co-Authors: Hiromitsu Takayama, Mariko Kitajima, Norio Aimi, Hayato Ishikawa, Muhammad AjiAbstract:A new yohimbine-type indole alkaloid (1) was isolated from the stem bark of Mitragyna africanus (WILLD.) collected in Nigeria, along with known seven Corynanthe-type oxindole alkaloids, two secoiridoids, three lignans, and a quinovic acid derivative. Their structures were elucidated by spectroscopic analyses.
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Structure revision of Mitragynaline, an indole alkaloid in Mitragyna speciosa
Tetrahedron Letters, 2001Co-Authors: Hiromitsu Takayama, Mariko Kitajima, Norio Aimi, Shin-ichiro Sakai, Hayato Ishikawa, Mika Kurihara, Ikram M. Said, Hiroko Seki, Kentaro Yamaguchi, Peter J. HoughtonAbstract:Abstract The structure of Mitragynaline, an indole alkaloid isolated from Malaysian Mitragyna speciosa , was revised as formula 3 by analysis of the NMR spectra measured at low temperature and by chemical transformation with DDQ oxidation from the known alkaloid mitragynine ( 5 ).
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structure elucidation and chiral total synthesis of a new indole alkaloid 9 methoxymitralactonine isolated from Mitragyna speciosa in malaysia
Tetrahedron, 2000Co-Authors: Hiromitsu Takayama, Mariko Kitajima, Mika Kurihara, Ikram M. Said, Norio AimiAbstract:Abstract A new Corynanthe-type indole alkaloid, (−)-9-methoxymitralactonine ( 1 ), having a highly conjugated system was isolated from the young leaves of Mitragyna speciosa in Malaysia, and its structure was first deduced by spectroscopic analysis and then confirmed by chiral-total synthesis starting from optically pure epoxy-ketone and 5-methoxy-3,4-dihydro-β-carboline. The chiral HPLC analysis demonstrated that the natural 9-methoxymitralactonine contained predominantly the (−)-enantiomer over the (+)-enantiomer in the ratio of 62:38.
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Structure Elucidation and Chiral-Total Synthesis of a New Indole Alkaloid, (−)-9-Methoxymitralactonine, Isolated from Mitragyna speciosa in Malaysia
Tetrahedron, 2000Co-Authors: Hiromitsu Takayama, Mariko Kitajima, Mika Kurihara, Ikram M. Said, Norio AimiAbstract:Abstract A new Corynanthe-type indole alkaloid, (−)-9-methoxymitralactonine ( 1 ), having a highly conjugated system was isolated from the young leaves of Mitragyna speciosa in Malaysia, and its structure was first deduced by spectroscopic analysis and then confirmed by chiral-total synthesis starting from optically pure epoxy-ketone and 5-methoxy-3,4-dihydro-β-carboline. The chiral HPLC analysis demonstrated that the natural 9-methoxymitralactonine contained predominantly the (−)-enantiomer over the (+)-enantiomer in the ratio of 62:38.
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New indole alkaloids from the leaves of Malaysian Mitragyna speciosa
Tetrahedron, 1998Co-Authors: Hiromitsu Takayama, Mariko Kitajima, Mika Kurihara, Ikram M. Said, Norio AimiAbstract:Abstract Three new monoterpenoid indole alkaloids, i.e., 3,4,5,6-tetradehydromitragynine, mitralactonal, and mitrasulgynine carrying a sulfonate function, were isolated, together with seven known compounds, from the leaves of Mitragyna speciosa native to Malaysia.