The chelating treatment is not useful in human's intoxication with acute herbicidal organic arsenic.

The clinical manifestations of acute organic arsenic intoxication in humans have seldom been described and the associated treatment has been thought to be the same as that of acute inorganic arsenic intoxication. We have studied a collection of patients from 1996 to 2001 who called the Poison Control Center of Kaohsiung Medical University Hospital asking for information regarding acute organic arsenic intoxication. The 17 patients ranged in age from 23 to 64 years old, with 5 females and 12 males. The cause of arsenic ingestion was attempted suicide. Abdominal pain and vomiting were the main symptoms. There were no differences in results between patients treated with and those treated without chelating agents. We therefore believe that the results of acute organic intoxication are not same as acute inorganic intoxication and it is unnecessary to use chelating agents in such conditions.

Isolation and characterization of an active compound from black soybean [Glycine max (L.) Merr.] and its effect on proliferation and differentiation of human leukemic U937 cells.

Black soybean [Glycine max (L.) Merr.] has been used as a health food and herb in China for hundreds of years. In the present study, we purified a unique polysaccharide component from black soybean (PSBS) and found that it indirectly inhibits proliferation and induces differentiation of human leukemic U937 cells via activation of mononuclear cells (MNCs). We prepared conditioned media (MNC-CM) by incubating MNCs from human peripheral blood with or without PSBS (PSBS-MNC-CM and normal MNC-CM, respectively). Treatment of human leukemic U937 cells with PSBS-MNC-CM significantly inhibited proliferation of U937 cells, reducing their growth by 98.5%. Furthermore, PSBS-MNC-CM induced U937 cells to differentiate into mature monocytes/macrophages (83% by morphological examination and 90% by the nitroblue tetrazolium test). Neither PSBS alone nor normal MNC-CM had such effects. The molecular weight of PSBS was about 480 000 by gel filtration. Structural analysis of PSBS revealed that (1,6)-alpha-D-glucan might be its major active component. Our results suggest that the PSBS may inhibit proliferation and induce differentiation in human leukemic U937 cells by activating the immune response of MNCs.

Anti-inflammatory effects of the partially purified extract of radix Stephaniae tetrandrae: comparative studies of its active principles tetrandrine and fangchinoline on human polymorphonuclear leukocyte functions.

We hypothesized that prevention of neutrophil from activation may underlie the myocardial protective effect of the specially processed extract of radix Stephaniae tetrandrae (SPRST). Inflammatory responses in isolated peripheral human neutrophils were studied in the presence or absence of SPRST. SPRST (1-10 microg/ml) concentration-dependently prevented N-formyl-methionyl-leucyl-phenylalanine (fMLP)- or leukotriene B(4) (LTB(4))-induced neutrophil adhesion and transmigration. Comparable results were also observed in neutrophils pretreated with fangchinoline (Fan) or tetrandrine (Tet), two active components in SPRST. It has been reported that neutrophil adhesion/transmigration is mainly Mac-1 (CD11b/CD18)-dependent and could be modulated by reactive oxygen species (ROS) production. SPRST, Tet, and Fan diminished fMLP- or LTB4-induced Mac-1 up-regulation and ROS production. SPRST, Fan, Tet, and verapamil impaired fMLP-induced rapid intracellular alkalization, an essential mechanism for neutrophil ROS production, and [Ca(2+)](i) increment, suggesting that a calcium dependent pathway might be involved. Direct G protein activation by AlF(4)(-) also triggered [Ca(2+)](i) increment and adhesion that could be abolished by pertussis toxin and were partially reversed by SPRST, Fan, and Tet. These results reveal that inhibition of neutrophil adhesion and transmigration may account for SPRST's myocardial protective effect. This effect of SPRST may be mediated by component(s) in addition to Tet and Fan because combination of 0.1 microg/ml of Tet and Fan did not mimic the effect of SPRST. We conclude that SPRST exerts anti-inflammatory effects by interfering with ROS production and Ca(2+) influx through G protein modulation to prevent Mac-1 up-regulation in neutrophil activation.

Cytotoxic principles from Ventilago leiocarpa.

Three new anthraquinones, islandicin 4-methyl ether (1), 1,2,6-trihydroxy-7,8-dimethoxy-3-methylanthraquinone (2), and 2-hydroxyemodin 1-methyl ether (3) as well as two known triterpenoids [taraxerol (4), lupeol (5)], six anthraquinones [chrysophanol (6), islandicin (8), parietin (9), emodin (10), catenarin (11), skyrin (15)], a 2,3-dihydroflavonol [(+)-aromadendrin (12)], two benzisochromanquinones [ventiloquinone K (13) and ventiloquinone I (14)], and stigmasterol (7) were isolated from Ventilago leiocarpa. The cytotoxicity of these compounds to various tumor cell lines was evaluated, and compound 15 significantly suppressed growth of HeLa, Vero, K562, Raji, Wish, and Calu-1 tumor cell lines. With the exception of K562 cells, the proliferation of other tumor cell lines was inhibited by compounds 3 and 10.

Regulation of cell proliferation, gene expression, production of cytokines, and cell cycle progression in primary human T lymphocytes by piperlactam S isolated from Piper kadsura.

Effects of piperlactam S (C(17)H(13)NO(4); mol. wt. 295) isolated from Piper kadsura on phytohemagglutinin (PHA) stimulated cell proliferation were studied in primary culture of human T cells. The results showed that piperlactam S suppressed T cell proliferation at about 0 to 12 h after stimulation with PHA. Synthesis of total cellular proteins and RNA in activated cell cultures was also suppressed. The inhibitory action of piperlactam S was not through direct cytotoxicity. Cell cycle analysis indicated that piperlactam S arrested the cell cycle progression of activated T cells from the G(1) transition to the S phase. In an attempt to further localize the point in the cell cycle at which arrest occurred, a set of key regulatory events leading to the G(1)/S boundary, including gene expression of cytokines and c-Fos protein synthesis, was examined. Piperlactam S suppressed, in activated T lymphocytes, the production and mRNA expression of cytokines such as interleukin-2 (IL-2), IL-4, and interferon-gamma in a dose-dependent manner. In addition, Western blot analysis indicated that c-Fos protein expressed in activated T lymphocytes was decreased by piperlactam S. Results of kinetic study indicated that inhibitory effects of piperlactam S on IL-2 mRNA expressed in T cells might be related to blocking c-Fos protein synthesis. Thus, the suppressant effects of piperlactam S on proliferation of T cells activated by PHA seemed to be mediated, at least in part, through inhibition of early transcripts of T cells, especially those of important cytokines, IL-2, IL-4, and arresting cell cycle progression in the cells.

Anti-herpes simplex virus type-1 flavonoids and a new flavanone from the root of Limonium sinense.

From the root of Limonium sinense (Girard) Ktze a new (2R,3S)-3,5,7,4'-tetrahydroxy-3',5'-dimethoxyflavanone was isolated and named isodihydrosyringetin (3), together with nine other known compounds, (-)-epigallocatechin 3-O-gallate (1), samarangenin B (2), myricetin (4), myricetin 3-O-alpha-rhamnopyranoside (5), quercetin 3-O-alpha-rhamnopyranoside (6), (-)-epigallocatechin (7), gallic acid (8), N-trans-caffeoyltyramine (9), and N-trans-feruloyltyramine (10). All of them were examined for their inhibitory effects on herpes simplex virus type-1 (HSV-1) replication in Vero cells. Both compounds 1 and 2 exhibited potent inhibitory activities in HSV-1 replication. Comparison of the IC50 values indicated that compounds 1 and 2 had higher inhibitory activities than the positive control acyclovir (38.6 +/- 2.6 vs. 55.4 +/- 5.3 microM, P < 0.001; 11.4 +/- 0.9 vs. 55.4 +/- 5.3 microM, P < 0.0005). Cytotoxicity was unlikely involved because no cell deaths were observable in the Vero cells following 5 day treatments with compound 1 or 2.

Flavonoids and phenolics from Limonium sinense.

From the aerial part of Limonium sinense (Girard) Ktze, a new flavonol glycoside, myricetin 3-O-(2"-O-p-hydroxybenzoyl)-alpha-rhamnopyranoside has been isolated together with known flavonols, flavonol glycosides, flavonol glycoside gallates, flavones, flavanones, flavan-3-ols and gallic acid. The structural determinations of these compounds were based on spectral analyses.

Cytotoxic biflavonoids from Selaginella delicatula.

Four new biflavonoids-robustaflavone 4'-methyl ether (1), robustaflavone 7,4'-dimethyl ether (2), 2",3" -dihydrorobustaflavone 7,4', -dimethyl ether (3), and 2",3" '-dihydrorobustaflavone 7,4', 7"-trimethyl ether (4)-as well as two known biflavonoids, robustaflavone and amentoflavone, and three caffeoylquinic acids, 3,5-di-O-caffeoylquinic acid, 3, 4-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid, were isolated from Selaginella delicatula. The structures of the new compounds were established by spectroscopic analysis and chemical modification. The cytotoxic activity of these compounds on various tumor cell lines was evaluated, and both compounds 1 and 3 significantly suppressed the growth of Raji and Calu-1 tumor cell lines.

Protein constituent contributes to the hypotensive and vasorelaxant activities of Cordyceps sinensis.

Cordyceps sinensis is a herb medicine in China for the treatment of general debility after sickness and for persons of advanced age. In the present study, cordyceps sinensis was extract by phosphate buffer saline (PBS) and dialyzed overnight against PBS using a membrane cut off at 3,500 dalton molecular weight. The resulting macromolecule fraction (defined as CS) was assayed in anesthetized rats for hypotensive effects and in isolated aorta for vasorelaxant effects. Intravenous injection of CS (8,16, 24 and 32 mg/kg, respectively) suppressed significantly the mean arterial pressure (MAP) in a dose-dependent manner. 32 mg/kg of CS induces the maximal hypotensive response with a 58 +/- 4 mm Hg (from 107 +/- 6 to 49 +/- 3 mm Hg) change in MAP and a over 45 min action duration. In aortic rings precontracted with phenylephrine treatment with CS between 0.5 and 500 microg/ml induced dose dependent relaxation. Maximal vasorelaxant response evoked by 150 microg/ml CS was 68.9 +/- 7.3%. Furthermore, CS-induced vasorelaxation is mediated by the endothelium possibly by stimulating the release of the nitric oxide and endothelium-derived hyperpolarizing factor. In conclusion, the present study revealed that presence of a constituent in CS which reduces MAP by relaxing the vascular beds directly. However, the effect may be caused by a single active ingredient or by the combined action of many active agents found in the extract.

Immunomodulatory principles of Dichrocephala bicolor.

From the ethanolic extract of Dichrocephala bicolor eight compounds-4,5-dicaffeoyl quinic acid (1); 3,4-dicaffeoyl quinic acid (2); 3,5-dicaffeoyl quinic acid (3); ethyl 4,5-dicaffeoyl quinate (4); methyl 3,5-dicaffeoyl quinate (5); 5-caffeoyl quinic acid (6); caffeic acid (7); and quercetin-3-O-rutinoside (8)-were isolated and identified. All of them were selected for immunopharmacological activity testing. Human mononuclear cells (HMNC) were used as target cells. Cell proliferation was determined by 3H-thymidine uptake. Compounds 2 and 6 potently enhanced HMNC proliferation and interferon-gamma production. Enhancement mechanisms may involve the increase of cytokines production.

Effects of methanol extract of Chansu on hypothalamic-pituitary-testis function in rats.

Chansu, a galenical preparation of the dried white venom of Chinese Bufo bufo gargarizans, is one of the major components of Kyushin, a traditional Chinese medicine. Kyushin is reported to have a cardiotonic effect that has been suggested to be due to the action of bufadienolides such as bufalin and cinobufagin. Recently, we found that administration of bufalin in male rats diminished the luteinizing hormone (LH) response to gonadotropin-releasing hormone (GnRH) and the secretion of testosterone both in vivo and in vitro. These observations suggest that Chansu may possess hypogonadal effects in male rats. In the present study, the effects of the methanol extract of Chansu on hypothalamic-pituitary-testicular function in male rats were examined. Crude Chansu was extracted by methanol and purified by a Sep-Pak C18 column. No activity of bufalin, cinobufagin, estradiol, or digoxin in purified methanol extract was detected; all Chansu used in this study was the purified methanol extract. A single intravenous injection of Chansu resulted in a decrease of the basal (20% to 55%) and human chorionic gonadotropin (hCG)-induced (35% to 40%) levels of plasma testosterone and the GnRH-induced level of plasma LH (25% to 30%). Administration of Chansu in vitro decreased basal and hCG-stimulated testosterone production by 60% to 70% and 40% to 60%, respectively, as well as spontaneous and forskolin- or 3-isobutyl-1-methylxanthine (IBMX)-induced accumulation of adenosine 3',5'-cyclic monophosphate (cAMP) by 30% to 45% in rat testicular interstitial cells. Although LH release by rat anterior pituitary glands was diminished, GnRH release by the rat mediobasal hypothalamus was enhanced by administration of Chansu in vitro. These results suggest that the bufalin-free extracts of Chansu inhibit testosterone secretion in rats, in part, due to (1) a decreased production of testicular cAMP, (2) a decreased response of testosterone to gonadotropin, and (3) a reduction of the LH response to GnRH.

Cytotoxic constituents from the stems of Diospyros maritima.

One novel coumaric acid ester of lupeol, dioslupecin A (1), three naphthoquinones, 8'-hydroxyisodiospyrin (2), isodiospyrin (3), and plumbagin (4), three triterpenes, lupeol, lupenone and taraxerone, and four sterols, beta-sitosterol, stigmasterol, stigmast-4-en-3-one and ergosta-4,6,8(14),22-tetraen-3-one were isolated from the n-hexane extract of the stems of Diospyros maritima Blume. The structural determination of 1 was based on 1D and 2D NMR spectra (including 1H-1H COSY, 1H-13C COSY, and HMBC). All compounds were evaluated for in vitro cytotoxicity in 4 cancer cell lines. Compound 2 showed similar cytotoxicity against hepatoma (HEPA-3B, ED50 = 1.72 micrograms/ml), nasopharynx carcinoma (KB, ED50 = 1.85 micrograms/ml), colon carcinoma (COLO-205, ED50 = 2.24 micrograms/ml) and cervical carcinoma (HELA, ED50 = 1.92 micrograms/ml). Compounds 3 and 4 exhibited strong cytotoxicity against HEPA-3B, KB, COLO-205 and HELA (ED50 = 0.25, 1.81, 0.13 and 0.27 micrograms/ml for 3; ED50 = 0.87, 3.27, 0.56 and 0.35 micrograms/ml for 4, respectively.

Determination of wogonin in rat plasma by liquid chromatography and its pharmacokinetic application.

A high-performance liquid chromatographic method has been developed for the determination of wogonin in the rat plasma. After addition of an internal standard (clomipramine), plasma was deproteinized by acetonitrile and centrifuged for sample clean-up. The supernatant was separated by a reversed-phase column chromatography, identified by a photodiode-array detector, and quantified by ultraviolet detection at a wavelength of 275 nm. Acetonitrile-water-diethylamine (50:50:0.1, v/v/v, pH 3.0 adjusted by orthophosphoric acid) was used as the mobile phase. The method was applied to the pharmacokinetic study of wogonin in rats after a dose of mg/kg by intravenous administration. A biphasic phenomenon with a rapid distribution followed by a slower elimination phase was observed from the plasma concentration time profile.

High-performance liquid chromatographic determination of evodiamine in rat plasma: application to pharmacokinetic studies.

A previously published simple and sensitive high-performance liquid chromatographic method for determination and identification of rutaecarpine in rat plasma was used for evodiamine determination. However, the ultraviolet detection was not 344 nm, but 227 nm. The method was applied to a pharmacokinetic study of evodiamine in rats after 2 mg/kg intravenous administration. A biphasic phenomenon with a rapid distribution followed by a slower elimination phase was observed from the plasma concentration-time curve. Compartmental analysis yielded a two-compartment model.

High-performance liquid chromatographic determination of rutaecarpine in rat plasma: application to a pharmacokinetic study.

A simple and sensitive high-performance liquid chromatographic method for determination and identification of rutaecarpine in rat plasma has been developed. Up to 0.1 ml of plasma containing rutaecarpine was deproteinized by acetonitrile, which contained an internal standard (paeonol). The supernatant was injected onto a reversed-phase column using a acetonitrile-water-orthophosphoric acid (85%) (60:40:0.1, v/v/v, pH 2.5-2.8) as the mobile phase and ultraviolet detection at 344 nm. It was applied to the pharmacokinetic study of rutaecarpine in rat after a 2 mg/kg intravenous administration. A biphasic process with a rapid distribution followed by a slower elimination phase was observed from the plasma concentration-time curve. Compartmental analysis yielded a two-compartment model.

Pharmacokinetics of honokiol after intravenous administration in rats assessed using high-performance liquid chromatography.

A simple and sensitive high-performance liquid chromatographic method for the identification and determination of honokiol in rat plasma has been developed. Up to 0.1 ml of plasma containing honokiol was deproteinized with acetonitrile, which contained an internal standard (paeonol). The supernatant was injected onto a reversed-phase C18 column using acetonitrile-water (70:30, v/v, adjusted to pH 2.5-2.8 with orthophosphoric acid) as the mobile phase and ultraviolet detection at 290 nm, followed by UV spectrum identification (between 220 and 380 nm) with a photodiode-array detector. The method was applied to pharmacokinetic studies of honokiol in rat following 5 or 10 mg/kg intravenous administration. A biphasic process consisting of a rapid distribution phase followed by a slower elimination phase was observed from the plasma concentration-time curves. Compartmental analysis yielded a two-compartment model.

The vasorelaxant effect of evodiamine in rat isolated mesenteric arteries: mode of action.

The roles of the endothelium, Ca2+ and K+ fluxes in the evodiamine-induced attenuation of vascular contractile responses to vasoactive agents were examined. The results showed that: (1) in rat mesenteric artery rings, evodiamine elicited a concentration-dependent attenuation in the contractile response generated by phenylephrine. The inhibitory potency was greater for intact than for endothelium-denuded preparations. Thus, the vasodilator action of evodiamine appeared to be partially endothelium-interactive (dependent). (2) Evodiamine pretreatment had a greater inhibitory effect on the phenylephrine-induced tonic contraction (via Ca2+ influx) than on the phasic contraction (via Ca2+ release). In addition, evodiamine was more potent to inhibit the restoration by CaCl2 of contractile responses to phenylephrine than a potassium depolarizing solution in media that had been kept calcium-free. These results suggest that block of the Ca2+ influx through receptor-mediated Ca2+ channels may be the major mechanism underlying the vasodilator effect of evodiamine. (3) A K+ channel blocker, tetraethylammonium, almost completely abolished the vasodilatation induced by minoxidil (a known K+ channel opener) but not evodiamine. The possible involvement of K+ channel activation of the vasodilator effect produced by evodiamine was therefore excluded.