piperidines and shogaol

Benjakul, a Thai traditional herbal preparation, comnprises five plants: Piper chaba, Piper sarmentosum, Piper interruptum, Plumbago indica, and Zingiber officinale. It has widely been used to treat cancer patients in folk medicine in Thailand. Benjakul extract, and its isolated compounds should be investigated for cytotoxic activity and analysis isolated compounds from chemical fingerprinting.. To study cytotoxicity ofBenjakul extract and its isolatedpure compounds against human small cell lung cancer cell line (NCI-HI 688) and in normal human lungfibroblast cell line (MRC-5) and analysis the content ofisolated compounds for quality control of Benjakul extract.. Bioassay-guided fractionation was used for isolated active compounds from ethanolic extract of Benjakul. Cytotoxic activity was carried using the SRB assay. HPLC method was applied to analyze six isolated compound contentfrom Benjakul extract.. The ethanolic extract ofBenjakul showed cytotoxicity against NCI-H1688 with IC50 value = 36.15±4.35 μg/ml. Hexane fraction as semi-separation by VLC showed the best cytotoxic activity (21.1 7±7.42 μg/ml). Six isolated compounds were identified as myristicin, plumbagin, methyl piperate, 6-shogaol, 6-gingerol and piperine. Plumbagin exhibited the highest cytotoxic activity and 6-shogaol was the second most effective cytotoxic constituent (IC50 values = 1.41±0.01 and 6.45±0.19 μg/ml, respectively). Piperine showed the highest content in both ofHPLC analysis and column chromatography separation.. Benjakul extract exhibited cytotoxicity against NCI-HI 688. Plumbagin and 6-shogaol are bioactive markers for cytotoxicity against this small cell lung cancer cell line. Chromatographic fingerprinting can be used to analyze six cytotoxic compounds isolatedfrom the ethanolic extract ofBenjakul.

Topics: Alkaloids; Benzodioxoles; Catechols; Cell Line, Tumor; Chromatography, High Pressure Liquid; Drug Screening Assays, Antitumor; Ethanol; Fatty Alcohols; Humans; Lung Neoplasms; Medicine, Traditional; Naphthoquinones; Piper; Piperidines; Plant Extracts; Plumbaginaceae; Polyunsaturated Alkamides; Small Cell Lung Carcinoma; Thailand; Zingiber officinale

Ginger (rhizomes of Zingiber officinale) has been shown to exert potent anti-emetic properties, but its mode of action has not yet been elucidated. Among its active constituents, [6]-, [8]- and [10]-gingerol as well as [6]-shogaol were shown in different in vivo studies to be at least partly responsible for the drug's anti-emetic properties. In an attempt to gain more insight into the mode of action of these compounds, three different in vitro models were used to investigate their effects on 5-HT(3) receptors (serotonin receptor subtype) in more detail: [(14)C]guanidinium influx into N1E-115 cells which express 5-HT(3) receptors, isotonic contractions of the isolated guinea-pig ileum and equilibrium competition binding studies using a radioactively labeled 5-HT(3) receptor antagonist ([(3)H]GR65630) (3-(5-methyl-1H-imidazol-4-yl)-1-(1-methyl-1H-indol-3-yl)-1-propanone). All four compounds inhibited the [(14)C]guanidinium influx through 5-HT(3) receptor channels as well as contractions of the guinea-pig ileum induced by SR57227A ((4-amino)-(6-chloro-2-pyridyl)l-piperidine hydrochloride), a highly selective 5-HT(3) receptor agonist. Both effects were concentration-dependent, with the following order of potency for both models: [6]-shogaol> or =[8]-gingerol>[10]-gingerol> or =[6]-gingerol. All compounds showed also weak anticholinergic and antineurokininergic activities in the guinea-pig ileum (acetylcholine and substance P are mediators of the 5-HT(3) receptor effect). The vanilloid receptor did not seem to be involved derived from experiments using capsazepine. None of the tested ginger substances, however, was able to displace [(3)H]GR65630 from its binding site (5-HT(3) receptor) neither on intact N1E-115 cells nor on the purified membranes of HEK-293 cells over-expressing the h5-HT(3) receptor. It may be concluded that [6]-, [8]-, [10]-gingerol and [6]-shogaol exert their anti-emetic effect at least partly by acting on the 5-HT(3) receptor ion-channel complex, probably by binding to a modulatory site distinct from the serotonin binding site. This may include indirect effects via receptors in the signal cascade behind the 5-HT(3) receptor channel complex such as substance P receptors and muscarinic receptors; this needs further investigation since ginger is effective against motion sickness which is cured by some vanilloids and by anticholinergics such as scopolamine.

Topics: Animals; Binding, Competitive; Carbon Radioisotopes; Catechols; Cations; Cell Line, Tumor; Dose-Response Relationship, Drug; Fatty Alcohols; Guanidine; Guinea Pigs; Humans; Ileum; Imidazoles; In Vitro Techniques; Indoles; Ion Channels; Isotonic Contraction; Male; Mice; Organic Cation Transport Proteins; Piperidines; Receptors, Serotonin, 5-HT3; Serotonin; Serotonin 5-HT3 Receptor Antagonists; Serotonin Antagonists; Sodium Channels; Substance P; Tritium; Tropisetron; Veratridine; Zingiber officinale