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  1. Ahmad W, Husain I, Ahmad N, Amir M, Sarafroz M, Ansari MA, et al.
    3 Biotech, 2020 Apr;10(4):165.
    PMID: 32206499 DOI: 10.1007/s13205-020-2154-1
    Boerhavia diffusa (BD) Linn. (Nyctaginaceae) is one of the most commonly used herbs in the Indian traditional system of medicine for the urinary disorders. The aim of the current investigation was to carry out initiation, development, and maintenance of BD callus cultures and quantitative estimation of punarnavine in plant and callus extracts. Leaves and stem of BD were used as explant for the tissue culture studies using Murashige and Skoog (MS) basal medium. MS Media comprising 2,4-Dichlorophenoxy acetic acid (2,4-D) (1 ppm) and 2,4-D (1 ppm) + Indole-3-acetic acid (IAA) (1.0 ppm) were found to yield friable callus from leaf explant; similarly, 2,4-D (0.3 ppm) + IAA (0.75 ppm) + Kinetin (0.3 ppm) and 2,4-D (0.5 ppm) + Naphthalene acetic acid (NAA) (1.5 ppm) + Kinetin (0.3 ppm) were found to yield friable callus from the stem explant. High-performance thin-layer chromatography method was been developed for the quantitative estimation of punarnavine (Rf = 0.73) using mobile phase containing toluene: ethyl acetate: formic acid in the ratio (7.0:2.5:0.7, v/v/v) at 262 nm. The validated method was found linear (r2 = 0.9971) in a wide range (100-1000 ng spot-1), precise, accurate, and robust. The values of limit of detection, LOD = 30.3 ng spot-1, and limit of quantification, LOQ = 100.0 ng spot-1. The robustness of the method was proved by applying the Box-Behnken design (BBD). The developed method found appropriate for the quality control of medicinal plants containing punarnavine as a constituent.
    Matched MeSH terms: Alkaloids
  2. Achike FI, Kwan CY
    Acta Pharmacol Sin, 2002 Aug;23(8):698-704.
    PMID: 12147191
    In an attempt to pharmacologically characterize the Chinese antihypertensive drug, tetrandrine, we observed in rat-tail arteries, an unusual contraction in tissues that were stimulated with high [KCl] and not those stimulated with phenylephrine. The characteristics of this contraction were studied.
    Matched MeSH terms: Alkaloids/pharmacology*
  3. Yusoff NH, Suhaimi FW, Vadivelu RK, Hassan Z, Rümler A, Rotter A, et al.
    Addict Biol, 2016 Jan;21(1):98-110.
    PMID: 25262913 DOI: 10.1111/adb.12185
    Mitragynine is the major psychoactive alkaloid of the plant kratom/ketum. Kratom is widely used in Southeast Asia as a recreational drug, and increasingly appears as a pure compound or a component of 'herbal high' preparations in the Western world. While mitragynine/kratom may have analgesic, muscle relaxant and anti-inflammatory effects, its addictive properties and effects on cognitive performance are unknown. We isolated mitragynine from the plant and performed a thorough investigation of its behavioural effects in rats and mice. Here we describe an addictive profile and cognitive impairments of acute and chronic mitragynine administration, which closely resembles that of morphine. Acute mitragynine has complex effects on locomotor activity. Repeated administration induces locomotor sensitization, anxiolysis and conditioned place preference, enhances expression of dopamine transporter- and dopamine receptor-regulating factor mRNA in the mesencephalon. While there was no increase in spontaneous locomotor activity during withdrawal, animals showed hypersensitivity towards small challenging doses for up to 14 days. Severe somatic withdrawal signs developed after 12 hours, and increased level of anxiety became evident after 24 hours of withdrawal. Acute mitragynine independently impaired passive avoidance learning, memory consolidation and retrieval, possibly mediated by a disruption of cortical oscillatory activity, including the suppression of low-frequency rhythms (delta and theta) in the electrocorticogram. Chronic mitragynine administration led to impaired passive avoidance and object recognition learning. Altogether, these findings provide evidence for an addiction potential with cognitive impairments for mitragynine, which suggest its classification as a harmful drug.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/pharmacology*
  4. Ismail NIW, Jayabalan N, Mansor SM, Müller CP, Muzaimi M
    Addict Biol, 2017 Jul;22(4):967-976.
    PMID: 26990882 DOI: 10.1111/adb.12385
    Kratom (Mitragyna speciosa) is a widely abused herbal drug preparation in Southeast Asia. It is often consumed as a substitute for heroin, but imposing itself unknown harms and addictive burdens. Mitragynine is the major psychostimulant constituent of kratom that has recently been reported to induce morphine-like behavioural and cognitive effects in rodents. The effects of chronic consumption on non-drug related behaviours are still unclear. In the present study, we investigated the effects of chronic mitragynine treatment on spontaneous activity, reward-related behaviour and cognition in mice in an IntelliCage® system, and compared them with those of morphine and Δ-9-tetrahydrocannabinol (THC). We found that chronic mitragynine treatment significantly potentiated horizontal exploratory activity. It enhanced spontaneous sucrose preference and also its persistence when the preference had aversive consequences. Furthermore, mitragynine impaired place learning and its reversal. Thereby, mitragynine effects closely resembled that of morphine and THC sensitisation. These findings suggest that chronic mitragynine exposure enhances spontaneous locomotor activity and the preference for natural rewards, but impairs learning and memory. These findings confirm pleiotropic effects of mitragynine (kratom) on human lifestyle, but may also support the recognition of the drug's harm potential.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/pharmacology*
  5. Yusof SR, Mohd Uzid M, Teh EH, Hanapi NA, Mohideen M, Mohamad Arshad AS, et al.
    Addict Biol, 2019 09;24(5):935-945.
    PMID: 30088322 DOI: 10.1111/adb.12661
    Mitragyna speciosa is reported to be beneficial for the management of chronic pain and opioid withdrawal in the evolving opioid epidemic. Data on the blood-brain barrier (BBB) transport of mitragynine and 7-hydroxymitragynine, the active compounds of the plant, are still lacking and inconclusive. Here, we present for the first time the rate and the extent of mitragynine and 7-hydroxymitragynine transport across the BBB, with an investigation of their post-BBB intra-brain distribution. We utilized an in vitro BBB model to study the rate of BBB permeation of the compounds and their interaction with efflux transporter P-glycoprotein (P-gp). Mitragynine showed higher apical-to-basolateral (A-B, i.e. blood-to-brain side) permeability than 7-hydroxymitragynine. 7-Hydroxymitragynine showed a tendency to efflux, with efflux ratio (B-A/A-B) of 1.39. Both were found to inhibit the P-gp and are also subject to efflux by the P-gp. Assessment of the extent of BBB transport in vivo in rats from unbound brain to plasma concentration ratios (Kp,uu,brain ) revealed extensive efflux of both compounds, with less than 10 percent of unbound mitragynine and 7-hydroxymitragynine in plasma crossing the BBB. By contrast, the extent of intra-brain distribution was significantly different, with mitragynine having 18-fold higher brain tissue uptake in brain slice assay compared with 7-hydroxymitragynine. Mitragynine showed a moderate capacity to accumulate inside brain parenchymal cells, while 7-hydroxymitragynine showed restricted cellular barrier transport. The presented findings from this systematic investigation of brain pharmacokinetics of mitragynine and 7-hydroxymitragynine are essential for design and interpretation of in vivo experiments aiming to establish exposure-response relationship.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/pharmacokinetics*
  6. Parthasarathy S, Ramanathan S, Ismail S, Adenan MI, Mansor SM, Murugaiyah V
    Anal Bioanal Chem, 2010 Jul;397(5):2023-30.
    PMID: 20454783 DOI: 10.1007/s00216-010-3707-7
    A new solid phase extraction method for rapid high performance liquid chromatography-UV determination of mitragynine in plasma has been developed. Optimal separation was achieved with an isocratic mobile phase consisting of acetonitrile-ammonium acetate buffer, 50 mM at pH 5.0 (50:50, v/v). The method had limits of detection and quantification of 0.025 and 0.050 microg/mL, respectively. The method was accurate and precise for the quantitative analysis of mitragynine in human and rat plasma with within-day and between-day accuracies between 84.0 and 109.6%, and their precision values were between 1.7 and 16.8%. Additional advantages over known methods are related to the solid phase extraction technique for sample preparation which yields a clean chromatogram, a short total analysis time, requires a smaller amount of plasma samples and has good assay sensitivity for bioanalytical application. The method was successfully applied in pharmacokinetic and stability studies of mitragynine. In the present study, mitragynine was found to be fairly stable during storage and sample preparation. The present study showed for the first time the detailed pharmacokinetic profiles of mitragynine. Following intravenous administration, mitragynine demonstrated a biphasic elimination from plasma. Oral absorption of the drug was slow, prolonged and was incomplete, with a calculated absolute oral bioavailability value of 3.03%. The variations observed in previous pharmacokinetic studies after oral administration of mitragynine could be attributed to its poor bioavailability rather than to the differences in assay method, metabolic saturation or mitragynine dose.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/administration & dosage; Secologanin Tryptamine Alkaloids/blood*; Secologanin Tryptamine Alkaloids/pharmacokinetics
  7. Philipp AA, Wissenbach DK, Weber AA, Zapp J, Maurer HH
    Anal Bioanal Chem, 2011 Mar;399(8):2747-53.
    PMID: 21249338 DOI: 10.1007/s00216-011-4660-9
    Mitragyna speciosa (Kratom) is currently used as a drug of abuse. When monitoring its abuse in urine, several alkaloids and their metabolites must be considered. In former studies, mitragynine (MG), its diastereomer speciogynine (SG), and paynantheine and their metabolites could be identified in rat and human urine using LC-MS(n). In Kratom users' urines, besides MG and SG, further isomeric compounds were detected. To elucidate whether the MG and SG diastereomer speciociliatine (SC) and its metabolites represent further compounds, the phase I and II metabolites of SC were identified first in rat urine after the administration of the pure alkaloid. Then, the identified rat metabolites were screened for in the urine of Kratom users using the above-mentioned LC-MS(n) procedure. Considering the mass spectra and retention times, it could be confirmed that SC and its metabolites are so far the unidentified isomers in human urine. In conclusion, SC and its metabolites can be used as further markers for Kratom use, especially by consumption of raw material or products that contain a high amount of fruits of the Malaysian plant M. speciosa.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/metabolism; Secologanin Tryptamine Alkaloids/urine*; Secologanin Tryptamine Alkaloids/chemistry
  8. Lee MJ, Ramanathan S, Mansor SM, Tan SC
    Anal Biochem, 2020 06 15;599:113733.
    PMID: 32302607 DOI: 10.1016/j.ab.2020.113733
    An enzyme-linked immunosorbent assay for detection of mitragynine, other closely related Kratom alkaloids and metabolites was developed using polyclonal antibodies. Mitragynine was conjugated to a carrier protein, cationized-bovine serum albumin using Mannich reaction. The synthesized antigen was injected into rabbits to elicit specific polyclonal antibodies against mitragynine. An enzyme conjugate was synthesized for evaluating its performance with the antibodies produced. The assay had an IC50 of 7.3 ng/mL with a limit of detection of 15 ng/mL for mitragynine. Antibody produced have high affinity for mitragynine (100%), other closely related Kratom alkaloids such as paynantheine (54%), speciociliatine (63%), 7α-hydroxy-7H-mitragynine (83%) and cross-reacted with metabolites 9-O-demethyl mitragynine (79%), 16-carboxy mitragynine (103%), 9-O-demethyl mitragynine sulfate (263%), 9-O-demethyl mitragynine glucuronide (60%), 16-carboxy mitragynine glucuronide (60%), 9-O-demethyl-16-carboxy mitragynine sulfate (270%) and 17-O-demethyl-16,17-dihydro mitragynine glucuronide (34%). It showed cross-reactivity less than 0.01% to reserpine, codeine, morphine, caffeine, methadone, amphetamine, and cocaine. Ten-fold dilution urine was used in the assay to reduce the matrix effects. The recovery ranged from 83% to 112% with variation coefficients in intraday and interday less than 8% and 6%, respectively. The ELISA turned out to be a convenient tool to diagnose mitragynine, other closely related Kratom alkaloids and metabolites in human urine samples.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/urine*
  9. Lee MJ, Ramanathan S, Mansor SM, Yeong KY, Tan SC
    Anal Biochem, 2018 02 15;543:146-161.
    PMID: 29248503 DOI: 10.1016/j.ab.2017.12.021
    A method using solid phase extraction and liquid chromatography-tandem mass spectrometry to quantitatively detect mitragynine, 16-carboxy mitragynine, and 9-O-demethyl mitragynine in human urine samples was developed and validated. The relevant metabolites were identified using multiple reaction monitoring in positive ionization mode using nalorphine as an internal standard. The method was validated for accuracy, precision, recovery, linearity, and lower limit of quantitation. The intra- and inter-day accuracy and precision were found in the range of 83.6-117.5% with coefficient of variation less than 13%. The percentage of recovery for mitragynine, 16-carboxy mitragynine, and 9-O-demethyl mitragynine was within the range of 80.1-118.9%. The lower limit of quantification was 1 ng/mL for mitragynine, 2 ng/mL for 16-carboxy mitragynine, and 50 ng/mL for 9-O-demethyl mitragynine. The developed method was reproducible, high precision and accuracy with good linearity and recovery for mitragynine, 16-carboxy mitragynine, and 9-O-demethyl mitragynine in human urine.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids
  10. Yap WF, Tay V, Tan SH, Yow YY, Chew J
    Antibiotics (Basel), 2019 Sep 17;8(3).
    PMID: 31533237 DOI: 10.3390/antibiotics8030152
    Seaweeds are gaining a considerable amount of attention for their antioxidant and antibacterial properties. Caulerpa racemosa and Caulerpa lentillifera, also known as 'sea grapes', are green seaweeds commonly found in different parts of the world, but the antioxidant and antibacterial potentials of Malaysian C. racemosa and C. lentillifera have not been thoroughly explored. In this study, crude extracts of the seaweeds were prepared using chloroform, methanol, and water. Total phenolic content (TPC) and total flavonoid content (TFC) were measured, followed by in vitro antioxidant activity determination using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Antibacterial activities of these extracts were tested against Methicillin-resistant Staphylococcus aureus (MRSA) and neuropathogenic Escherichia coli K1. Liquid chromatography-mass spectrometry (LCMS) analysis was then used to determine the possible compounds present in the extract with the most potent antioxidant and antibacterial activity. Results showed that C. racemosa chloroform extract had the highest TPC (13.41 ± 0.86 mg GAE/g), antioxidant effect (EC50 at 0.65 ± 0.03 mg/mL), and the strongest antibacterial effect (97.7 ± 0.30%) against MRSA. LCMS analysis proposed that the chloroform extracts of C. racemosa are mainly polyunsaturated and monounsaturated fatty acids, terpenes, and alkaloids. In conclusion, C. racemosa can be a great source of novel antioxidant and antibacterial agents, but isolation and purification of the bioactive compounds are needed to study their mechanism of action.
    Matched MeSH terms: Alkaloids
  11. Teo SP, Bhakta S, Stapleton P, Gibbons S
    Antibiotics (Basel), 2020 Dec 16;9(12).
    PMID: 33339285 DOI: 10.3390/antibiotics9120913
    The present study aimed to screen plants for bioactive compounds with potential antibacterial activities. In our efforts to evaluate plants from Borneo, we isolated and elucidated the structures of four natural products from the bioactive fraction of a chloroform extract of Goniothalamus longistipetes using various chromatographic and spectroscopic techniques. The bioactive compounds were identified as a known styryllactone, (+)-altholactone ((2S,3R,3aS,7aS)-3-hydroxy-2-phenyl-2,3,3a,7a-tetrahydrobenzo-5(4H)-5-one) (1), a new styryllactone, (2S,3R,3aS,7aS)-3-hydroxy-2-phenyl-2,3,3a,7a-tetrahydrobenzo-5(4H)-5-one) (2) as well as a new alkaloid, 2,6-dimethoxyisonicotinaldehyde (3) and a new alkenyl-5-hydroxyl-phenyl benzoic acid (4). 1 and 4 showed broad-spectrum anti-bacterial activities against Gram-positive and Gram-negative bacteria as well as acid-fast model selected for this study. Compound 2 only demonstrated activities against Gram-positive bacteria whilst 3 displayed selective inhibitory activities against Gram-positive bacterial strains. Additionally, their mechanisms of anti-bacterial action were also investigated. Using Mycobacterium smegmatis as a fast-growing model of tubercle bacilli, compounds 1, 2 and 4 demonstrated inhibitory activities against whole-cell drug efflux and biofilm formation; two key intrinsic mechanisms of antibiotic resistance. Interestingly, the amphiphilic compound 4 exhibited inhibitory activity against the conjugation of plasmid pKM101 in Escherichia coli using a plate conjugation assay. Plasmid conjugation is a mechanism by which Gram-positive and Gram-negative-bacteria acquire drug resistance and virulence. These results indicated that bioactive compounds isolated from Goniothalamus longistipetes can be potential candidates as 'hits' for further optimisation.
    Matched MeSH terms: Alkaloids
  12. Arjungi KN
    Arzneimittelforschung, 1976;26(5):951-6.
    PMID: 786304
    Areca cattechu Linn is commonly known as areca nut or betel nut. It is a very widely cultivated plant in eastern countries like India, Bangladesh, Ceylon, Malaya, the Philippines and Japan. The importance of this nut is due to its use for chewing purposes. It had an important place as a pharmaceutical in Ayurveda--the ancient Indian system of medicine--also in the Chinese medicinal practices. The pharmaceutical importance of areca nut is due to the presence of an alkaloid, arecoline. Synthetic arecoline hydrobromide is also shown to possess numerous pharmacological properties. Chewing of "betel quid" or areca nut is a typical oriental habit. Betel quid comprises betel leaf, areca nut, catechu, lime and sometimes also tobacco. It is shown that there exists a correlationship between betel quid or areca nut chewing habit and oral cancer. A number of investigators have been able to produce cellular changes such as leukoplakia by application of betel quid or areca nut extract to the buccal mucosa of different animal.
    Matched MeSH terms: Alkaloids/chemical synthesis
  13. Goh TB, Koh RY, Mordi MN, Mansor SM
    Asian Pac J Cancer Prev, 2014;15(14):5659-65.
    PMID: 25081682
    BACKGROUND: To investigate the antioxidant value and anticancer functions of mitragynine (MTG) and its silane-reduced analogues (SRM) in vitro.

    MATERIALS AND METHODS: MTG and SRM was analyzed for their reducing power ability, ABTS radical inhibition and 1,1-diphenyl-2-picryl hydrazylfree radicals scavenging activities. Furthermore, the antiproliferation efficacy was evaluated using MTT assay on K 562 and HCT116 cancer cell lines versus NIH/3T3 and CCD18-Co normal cell lines respectively.

    RESULTS: SRM and MTG demonstrate moderate antioxidant value with ABTS assay (Trolox equivalent antioxidant capacity (TEAC): 2.25±0.02 mmol trolox / mmol and 1.96±0.04 mmol trolox / mmol respectively) and DPPH (IC50=3.75±0.04 mg/mL and IC50=2.28±0.02 mg/mL respectively). Both MTG and SRM demonstrate equal potency (IC50=25.20±1.53 and IC50= 22.19±1.06 respectively) towards K 562 cell lines, comparable to control, betulinic acid (BA) (IC5024.40±1.26). Both compounds showed concentration-dependent cytototoxicity effects and exert profound antiproliferative efficacy at concentration > 100 μM towards HCT 116 and K 562 cancer cell lines, comparable to those of BA and 5-FU (5-Fluorouracil). Furthermore, both MTG and SRM exhibit high selectivity towards HCT 116 cell lines with selective indexes of 3.14 and 2.93 respectively compared to 5-FU (SI=0.60).

    CONCLUSIONS: These findings revealed that the medicinal and nutitional values of mitragynine obtained from ketum leaves that growth in tropical forest of Southeast Asia and its analogues does not limited to analgesic properties but could be promising antioxidant and anticancer or chemopreventive compounds.

    Matched MeSH terms: Secologanin Tryptamine Alkaloids/pharmacology*
  14. Hossain MA, Shah MD, Sakari M
    Asian Pac J Trop Med, 2011 Aug;4(8):637-41.
    PMID: 21914542 DOI: 10.1016/S1995-7645(11)60162-4
    OBJECTIVE: To analyse the chemical composition of different extracts of Merremia borneensis (M. borneensis) by gas chromatography-mass spectrometry (GC-MS).

    METHODS: The dried leaves powder was extracted with methanol at room temperature by using Soxhlet extractor. Methanol crude extracts of M. borneensis were extrastel with hexane, chloroform, ethyl acetate and butanol.

    RESULTS: Qualitative analyses of various organic crude extracts showed that majority of these are flavonoids, terpeniods, alkaloids and glycosides. Most of the identified compounds by GC-MS are biologically important. Further the M. borneensis leaf possesses certain characteristics that can be ascribed to cultivation on a domestic plantation.

    CONCLUSIONS: The suitable extracts for respective compounds can be chosen on the basis of above GC-MS analysis. All the major compounds from different extracts are biologically active molecules. Thus the identification of a good number of compounds from various extracts M. borneensis might have some ecological significance.

    Matched MeSH terms: Alkaloids/analysis*
  15. Alhuthali HM, Bradshaw TD, Lim KH, Kam TS, Seedhouse CH
    BMC Cancer, 2020 Jul 07;20(1):629.
    PMID: 32635894 DOI: 10.1186/s12885-020-07119-2
    BACKGROUND: Acute myeloid leukemia (AML) is a heterogenous hematological malignancy with poor long-term survival. New drugs which improve the outcome of AML patients are urgently required. In this work, the activity and mechanism of action of the cytotoxic indole alkaloid Jerantinine B (JB), was examined in AML cells.

    METHODS: We used a combination of proliferation and apoptosis assays to assess the effect of JB on AML cell lines and patient samples, with BH3 profiling being performed to identify early effects of the drug (4 h). Phosphokinase arrays were adopted to identify potential driver proteins in the cellular response to JB, the results of which were confirmed and extended using western blotting and inhibitor assays and measuring levels of reactive oxygen species.

    RESULTS: AML cell growth was significantly impaired following JB exposure in a dose-dependent manner; potent colony inhibition of primary patient cells was also observed. An apoptotic mode of death was demonstrated using Annexin V and upregulation of apoptotic biomarkers (active caspase 3 and cleaved PARP). Using BH3 profiling, JB was shown to prime cells to apoptosis at an early time point (4 h) and phospho-kinase arrays demonstrated this to be associated with a strong upregulation and activation of both total and phosphorylated c-Jun (S63). The mechanism of c-Jun activation was probed and significant induction of reactive oxygen species (ROS) was demonstrated which resulted in an increase in the DNA damage response marker γH2AX. This was further verified by the loss of JB-induced C-Jun activation and maintenance of cell viability when using the ROS scavenger N-acetyl-L-cysteine (NAC).

    CONCLUSIONS: This work provides the first evidence of cytotoxicity of JB against AML cells and identifies ROS-induced c-Jun activation as the major mechanism of action.

    Matched MeSH terms: Indole Alkaloids/pharmacology*; Indole Alkaloids/therapeutic use
  16. Japarin RA, Yusoff NH, Hassan Z, Müller CP, Harun N
    Behav Brain Res, 2021 02 05;399:113021.
    PMID: 33227244 DOI: 10.1016/j.bbr.2020.113021
    Kratom is a medicinal plant that exhibits promising results as an opiate substitute. However, there is little information regarding the abuse profile of its main psychoactive constituent, mitragynine (MG), particularly in relapse to drug abuse. Using the place conditioning procedure as a model of relapse, this study aims to evaluate the ability of MG to induce conditioned place preference (CPP) reinstatement in rats. To evaluate the cross-reinstatement effects, MG and morphine were injected to rats that previously extinguished a morphine- or MG-induced CPP. Following a CPP acquisition induced by either MG (10 and 30 mg/kg, i.p.) or morphine (10 mg/kg, i.p.), rats were subjected to repeated CPP extinction sessions. A low dose priming injection of MG or morphine produced a reinstatement of the previously extinguished CPP. In the second experiment of this study, a priming injection of morphine (1, 3 and 10 mg/kg, i.p.) dose-dependently reinstated an MG-induced CPP. Likewise, a priming injection of MG (3, 10 and 30 mg/kg, i.p.) was able to dose-dependently reinstate a morphine-induced CPP. The present study demonstrates a cross-reinstatement effect between MG and morphine, thereby suggesting a similar interaction in their rewarding motivational properties. The findings from this study also suggesting that a priming exposure to kratom and an opioid may cause relapse for a previously abused drug.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/administration & dosage; Secologanin Tryptamine Alkaloids/pharmacology*
  17. Yusoff NHM, Mansor SM, Müller CP, Hassan Z
    Behav Brain Res, 2018 06 01;345:65-71.
    PMID: 29499286 DOI: 10.1016/j.bbr.2018.02.039
    Mitragynine is the major alkaloid found in the leaves of M. speciosa Korth (Rubiaceae), a plant that is native to Southeast Asia. This compound has been used, either traditionally or recreationally, due to its psychostimulant and opioid-like effects. Recently, mitragynine has been shown to exert conditioned place preference (CPP), indicating the rewarding and motivational properties of M. speciosa. Here, the involvement of GABAB receptors in mediating mitragynine reward is studied using a CPP paradigm in rats. First, we examined the effects of GABAB receptor agonist baclofen (1.25, 2.5 and 5 mg/kg) on the acquisition of mitragynine (10 mg/kg)-induced CPP. Second, the involvement of GABAB receptors in the expression of mitragynine-induced CPP was tested. We found that the acquisition of mitragynine-induced CPP could be blocked by higher doses (2.5 and 5 mg/kg) of baclofen. Baclofen at a high dose inhibited locomotor activity and caused a CPP. Furthermore, we found that baclofen (2.5 and 5 mg/kg) also blocked the expression of mitragynine-induced CPP. These findings suggest that both, the acquisition and expression of mitragynine's reinforcing properties is controlled by the GABAB receptor.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/pharmacology*
  18. Yusoff NHM, Mansor SM, Müller CP, Hassan Z
    Behav Brain Res, 2017 08 14;332:1-6.
    PMID: 28559179 DOI: 10.1016/j.bbr.2017.05.059
    Mitragynine is the main psychoactive ingredient of the herbal drug preparation Kratom (Ketum), derived from the plant Mitragyna speciosa. Kratom is a widely abused drug in Southeast Asian and has a psychostimulant profile at low-medium doses, while high doses have opioidergic effects. Mitragynine was shown to possess opiate receptor affinity. However, its role in the behavioural effects of mitragynine is unclear. Here we asked whether the reinforcing effects of mitragynine are mediated by opiate receptors using a conditioned place preference (CPP) paradigm in rats. In the first experiment we tested the effects of the opiate receptor antagonist naloxone (0.1, 0.3 and 1.0mg/kg) on the acquisition of mitragynine (10mg/kg)-induced CPP. In the second experiment, we tested the involvement of opiate receptors in the expression of mitragynine-induced CPP in rats. We found that naloxone suppresses the acquisition of mitragynine-induced CPP. This effect was already evident at a dose of naloxone (0.1mg/kg) which, by itself, had no conditioned place aversion (CPA) effect. Higher doses of naloxone induced a CPA and blocked mitragynine-induced CPP. In contrast, naloxone had no effect on the expression of mitragynine-induced CPP. These findings suggest that the acquisition, but not the expression of the reinforcing effects of mitragynine is mediated by opiate receptors.
    Matched MeSH terms: Secologanin Tryptamine Alkaloids/isolation & purification; Secologanin Tryptamine Alkaloids/pharmacology*
  19. Johari SA, Mohtar M, Mohammad SA, Sahdan R, Shaameri Z, Hamzah AS, et al.
    Biomed Res Int, 2015;2015:823829.
    PMID: 25710030 DOI: 10.1155/2015/823829
    28 new pyrrolidine types of compounds as analogues for natural polyhydroxy alkaloids of codonopsinine were evaluated for their anti-MRSA activity using MIC and MBC value determination assay against a panel of S. aureus isolates. One pyrrolidine compound, MFM 501, exhibited good inhibitory activity with MIC value of 15.6 to 31.3 μg/mL against 55 S. aureus isolates (43 MRSA and 12 MSSA isolates). The active compound also displayed MBC values between 250 and 500 μg/mL against 58 S. aureus isolates (45 MRSA and 13 MSSA isolates) implying that MFM 501 has a bacteriostatic rather than bactericidal effect against both MRSA and MSSA isolates. In addition, MFM 501 showed no apparent cytotoxicity activity towards three normal cell lines (WRL-68, Vero, and 3T3) with IC50 values of >625 µg/mL. Selectivity index (SI) of MFM 501 gave a value of >10 suggesting that MFM 501 is significant and suitable for further in vivo investigations. These results suggested that synthetically derived intermediate compounds based on natural products may play an important role in the discovery of new anti-infective agents against MRSA.
    Matched MeSH terms: Alkaloids/administration & dosage*; Alkaloids/chemistry
  20. Salhi N, Mohammed Saghir SA, Terzi V, Brahmi I, Ghedairi N, Bissati S
    Biomed Res Int, 2017;2017:7526291.
    PMID: 29226147 DOI: 10.1155/2017/7526291
    Aim: This study investigated the antifungal properties of aqueous extracts obtained from indigenous plants that grow spontaneously in the Northern Sahara of Algeria. The activities of these plants in controlling two fungal species that belong to Fusarium genus were evaluated in an in vitro assay.

    Materials and Methods: Fresh aerial parts of four plant species (Artemisia herba alba, Cotula cinerea, Asphodelus tenuifolius, and Euphorbia guyoniana) were collected for the preparation of aqueous extracts. Two levels of dilution (10% and 20%) of the pure extracts were evaluated against Fusarium graminearum and Fusarium sporotrichioides.

    Results: The results of this study revealed that the A. herba alba, C. cinerea, A. tenuifolius, and E. guyoniana aqueous extracts are effective at both concentrations of 10% and 20% for the Fusarium mycelia growth inhibition. In particular, A. tenuifolius extract is effective against F. graminearum, whereas F. sporotrichioides mycelium growth is strongly affected by the E. guyoniana 20% extract. The phytochemical characterization of the compositions of the aqueous extracts has revealed that the presence of some chemical compounds (tannins, flavonoids, saponins, steroids, and alkaloids) is likely to be responsible for the antifungal activities sought.

    Conclusion: The antifungal properties of A. herba alba, C. cinerea, A. tenuifolius, and E. guyoniana make these plants of potential interest for the control of fungi affecting both wheat yield and safety.

    Matched MeSH terms: Alkaloids/pharmacology; Alkaloids/chemistry
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