Antioxidative activity of natural products from plants

A variety of flavonoids, lignans, an alkaloid, a bisbenzyl, coumarins and terpenes isolated from Chinese herbs was tested for antioxidant activity as reflected in the ability to inhibit lipid peroxidation in rat brain and kidney homogenates and rat erythrocyte hemolysis. The pro-oxidant activities of the aforementioned compounds were assessed by their effects on bleomycin-induced DNA damage. The flavonoids baicalin and luteolin-7-glucuronide-6'-methyl ester, the lignan 4'-demethyldeoxypodophyllotoxin, the alkaloid tetrahydropalmatine, the bisbenzyl erianin and the coumarin xanthotoxol exhibited potent antioxidative activity in both lipid peroxidation and hemolysis assays. The flavonoid rutin and the terpene tanshinone I manifested potent antioxidative activity in the lipid peroxidation assay but no inhibitory activity in the hemolysis assay. The lignan deoxypodophyllotoxin, the flavonoid naringin and the coumarins columbianetin, bergapten and angelicin slightly inhibited lipid peroxidation in brain and kidney homogenates. It is worth stressing that the compounds with antioxidant effects in this assay, with the exception of tetrahydropalmatin and tanshinone I, have at least one free aromatic hydroxyl group in structure. Obviously, the aromatic hydroxyl group is very important for antioxidative effects of the compounds. None of the compounds tested exerted an obvious pro-oxidant effect.

Vasorelaxant effects of cardamonin and alpinetin from Alpinia henryi K. Schum

The vascular effects of cardamonin and alpinetin from Alpinia henryi K. Schum. were examined in the rat isolated mesenteric arteries. 1H and 13C nuclear magnetic resonance spectra showed that cardamonin is present in trans-form, and single-crystal radiographic structure revealed that alpinetin is present in S configuration. Both cardamonin and alpinetin produced a rightward shift in the concentration-response curve for phenylephrine in a noncompetitive manner, and they induced relaxation of phenylephrine-preconstricted arteries with respective mean inhibitory concentrations (IC50) of 9.3+/-0.6 microM and 27.5+/-2.8 microM. Both compounds also relaxed arteries preconstricted by endothelin I or U46619. Their relaxant effects were decreased in endothelium-removed rings. Pretreatment with N(G)-nitro-L-arginine methyl ester or methylene blue inhibited relaxation induced by both agents, and pretreatment with L-arginine reversed the effect of N(G)-nitro-L-arginine methyl ester on cardamonin-induced endothelium-dependent relaxation. The relaxant effects of cardamonin and alpinetin were unaffected by indomethacin (3 microM). Cardamonin and alpinetin inhibited 60 mM K+-induced contraction with respective IC50 of 11.5+/-0.3 microM and 37.9+/-3.6 microM. In addition, both agents inhibited the transient contraction induced by 3 microM phenylephrine or by 10 mM caffeine in Ca2+-free Krebs solution. Finally, these two agents also concentration dependently relax the arteries preconstricted by 1 microM phorbol 12,13-diacetate in Ca2+-free Krebs solution. These results indicate that purified cardamonin and alpinetin from A. henryi K. Schum. relaxed rat mesenteric arteries through multiple mechanisms. They induced both endothelium-dependent and -independent relaxation; the former is likely mediated by nitric oxide whereas the latter is probably mediated through nonselective inhibition of Ca2+ influx and intracellular Ca2+ release and inhibition of the protein kinase C-dependent contractile mechanism.

Structural features and anti-HIV-1 activity of novel polysaccharides from red algae Grateloupia longifolia and Grateloupia filicina

Since sulphated polysaccharides have antiviral activity in vitro, we examined the structure and antiretroviral activity of native sulphated galactans extracted from the red algae, Grateloupia filicina (GFP) and Grateloupia longifolia (GLP). The sulphate contents of GFP and GLPE (the 1,4-alpha-d-glucan-glucanohydrolase digest of GLP) were 25.7 and 18.5%, respectively. The sulphate ester groups were located at carbon 2 for GFP and at carbon 2 and 6 for GLPE. Antiretroviral activity was investigated with a primary isolate (PI) of HIV-1 and human peripheral blood mononuclear cells (PBMCs) rather than T-cell line adapted (TCLA) HIV-1 and T-cell lines because it is more representative of the in vivo situation. Both compounds and their derivatives had potent anti-HIV-1 activity when added at the time of infection, and 2h post-infection (EC50s 0.010-0.003microM, EC(90s) 0.87-0.33microM) and low cytotoxicity. Their potential medical application as virucidal vaginal formulations is discussed.

Immunomodulatory effect of a polysaccharide-enriched preparation of Codonopsis pilosula roots

1. A polysaccharide-enriched fraction (CPPS) was prepared from Codonopsis pilosula root extract utilizing a procedure that entailed extraction with aqueous buffer and precipitation with ethanol. 2. After administration of CPPS in drinking water to C57BL/6 mice at a dosage of 10 mg/L for 4 weeks, the splenocytes exhibited lowered mitogenic responses to Concanavalin A (ConA) and lipopolysaccharide (LPS). The in vitro production of reactive nitrogen intermediates was inhibited. 3. However, when oral administration of CPPS was prolonged to 8 weeks, there was a potentiation of ConA-stimulated and LPS-stimulated mitogenic responses. 4. When tested under in vitro conditions, CPPS augmented the mitogenic response of splenocytes to ConA. However, there was no effect on the pinocytic activity of mouse macrophages, nor was there any proliferative activity on mouse melanoma B16 cells.

Antidepressant effect of Yueju-Wan ethanol extract and its fractions in mice models of despair

AIM OF THE STUDY

Yueju-Wan (YJ), a traditional Chinese medicinal formula, is commonly used for the treatment of depression-related syndromes in China. This study was conducted to evaluate the antidepressant activity of YJ ethanol extract (YJ-E) and its four different fractions, the petroleum ether fraction (YJ-EA), ethyl acetate fraction (YJ-EB), n-butanol fraction (YJ-EC) and final aqueous fraction (YJ-ED).

MATERIALS AND METHODS

Two experimental despair animal models: the mice tail suspension test (TST) and the mice forced swimming test (FST) were used to evaluate the antidepressant activity of YJ-E and its fractions. These extracts or fractions were administered orally for 7 days, while the parallel positive control was given at the same time using fluoxetine hydrochloride (FLU) in TST and imipramine hydrochloride (IMI) in FST respectively.

RESULTS

YJ-E high dose (YJ-E2), YJ-EA, YJ-EC and the positive control groups could decrease the duration of immobility in the TST and FST and have no significant changes in locomotor activity. YJ-E low dose (YJ-E1), YJ-EB, YJ-ED and the vehicle solvent (VEH) control group have no obvious effect on these same tests.

CONCLUSIONS

In these despair animal models, YJ ethanol extract, the petroleum ether fraction and n-butanol fraction show potent antidepressant effects. The petroleum ether fraction and n-butanol fraction appear to be the active fractions of YJ-E.

Coumarins from the fruits of Cnidium monnieri

Two novel biscoumarins, cnidimonal (1) and cnidimarin (2), and two new coumarin derivatives, 5-formylxanthotoxol (3) and 2'-deoxymeranzin hydrate (4), were isolated from a traditional Chinese crude drug, the fruits of Cnidium monnieri, together with 15 known compounds. Among the known compounds, five of the minor compounds were isolated for the first time from this plant. The structures of 1-4 were determined with the use of spectroscopic methods.

Determination of hepatotoxic pyrrolizidine alkaloids by on-line high performance liquid chromatography mass spectrometry with an electrospray interface

The present study describes the determination of two different types of hepatotoxic pyrrolizidine alkaloids (PAs) and also distinguishing the hepatotoxic PAs from non-toxic ones by both in-source collision-induced dissociation high performance liquid chromatography mass spectrometry (CID-HPLC/MS) and HPLC/MS/MS (CID in the collision cell), using electrospray ionization. The mass spectra provided molecular ions and characteristic fragment ions, which could be used readily for a rapid identification of different types of PAs. Applications of both in-source CID-HPLC/MS and HPLC/MS/MS analytical methods were successful for the determination of PAs in blood samples obtained from rats dosed with PAs and in the PA-containing plant. The results demonstrated that the developed HPLC/MS methods with two different CID techniques provided a very simple and rapid analysis for an unequivocal diagnosis of PA poisoning and for definitive identification of PAs in plants or herbal medicines.

Examination of coumarins, flavonoids and polysaccharopeptide for antibacterial activity

1. Coumarins, flavonoids and polysaccharopeptide were tested for antibacterial activity. 2. The bacteria used for this study included clinical isolates of Staphylococcus aureus, Shigella flexneri, Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa. 3. Most of the coumarins tested failed to inhibit the bacteria at 25 mg/l. Edultin at 128 mg/l inhibited 4 of the 8 P. aeruginosa strains and 1 of the S. aureus strains tested. O-acetylcolumbianetin and imperatorin did not inhibit any isolate, even at 128 mg/l. 4. When tested at the dose of 128 mg/l, the flavonoids (rutin, naringin and baicalin) inhibited 25% or less of P. aeruginosa and only baicalin was active against S. aureus. 5. Arbutin and 4-(beta-D-glucopyranosyloxyl)-benzaldehyde inhibited 3 of the 8 P. aeruginosa strains when tested at 128 mg/l. 6. Polysaccharopeptide from the fungus Coriolus versicolor failed to inhibit any P. aeruginosa or S. aureus strain at 128 mg/l.

Tribulusamide A and B, new hepatoprotective lignanamides from the fruits of Tribulus terrestris: indications of cytoprotective activity in murine hepatocyte culture

Tribulusamides A (1) and B (2), new lignanamides embracing two cinnamic amide parts joined in a cis configuration, were isolated from the fruits of Tribulus terrestris, together with four known compounds, N-trans-feruloyltyramine (3), terrestriamide (4), N-trans-coumaroyltyramine (5), and beta-sitosterol. The structures were elucidated by 2D-NMR spectroscopy. Addition of compounds 1-5, especially 1 and 2, to primary cultured mouse hepatocytes significantly prevented cell death induced by D-galactosamine (D-GalN)/tumor necrosis factor alpha (TNF-alpha).

Investigations on the protective action of Condonopsis pilosula (Dangshen) extract on experimentally-induced gastric ulcer in rats

The action of Codonopsis pilosula extract in 5 animal models of gastric ulcer was investigated. It was found that the extract had higher efficacy on gastric ulcer induced by stress, acetic acid and sodium hydroxide and little significant effect on ulcers induced by pyloroligature and indomethacin. The C. pilosula extract was also capable of reducing gastric acid pepsin secretion. It is possible that inhibition of gastrointestinal movement and propulsion is one of the mechanisms underlying the antiulcer action of C. pilosula extract.

Characterization of two structural forms of otonecine-type pyrrolizidine alkaloids from Ligularia hodgsonii by NMR spectroscopy

Clivorine (1) and ligularine (2), two hepatotoxic otonecine-type pyrrolizidine alkaloids isolated from Ligularia hodgsonii, an antitussive traditional Chinese medicine, were investigated in CDCl(3) and D(2)O by various NMR techniques to delineate why this type of alkaloid displays uncharacteristic solubility properties by dissolving in both nonpolar organic and aqueous solutions. The results demonstrated that both alkaloids exist in a non-ionized form in CDCl(3), but in an ionized form in D(2)O, suggesting that this unique dual solubility may play a role in the intoxication resultant from consumption of water extracts of herbs, including herbal teas, containing otonecine-type pyrrolizidine alkaloids.

Identification of medicinal plants used as Tibetan Traditional Medicine jie-ji

AIM OF THE STUDY

Based on the authors' collection of specimens used as jie-ji in local Tibetan areas, China, and taxonomic determination, this paper aims to give a list of medicinal plants as jie-ji, formally identify the ones recognized as jie-ji ga-bao or jie-ji na-bao and to offer basic data for further studies on these Tibetan herbs.

MATERIALS AND METHODS

Local herbalists were visited in Tibetan areas, China to observe which plants were being used as jie-ji. Samples of the indigenous plants were collected at the same time. Also, the medicinal plants as jie-ji were taxonomically identified.

RESULTS

A list of medicinal plants including 10 species of jie-ji in local Tibetan areas is given, including their morphological pictures used for identification.

CONCLUSIONS

The origin of jie-ji is from 10 species of the Section Cruciata, Genus Gentiana (Gentianaceae). five species with dark blue flowers are used as jie-ji na-bao, the other five with white flowers are used as jie-ji ga-bao. Also, Gentiana macrophylla Pall. with dark blue flowers in the Section Cruciata, Genus Gentiana is not the original plant of jie-ji na-bao. The species endemic to the province are used as the original plants of jie-ji only in local Tibetan area of the province. Finally, the drug use of jie-ji in Traditional Tibetan Medicine is reasonable and it is efficacious.

Propofol suppresses proliferation and invasion of gastric cancer cells via downregulation of microRNA-221 expression

Propofol is one of the extensively and commonly used intravenous anesthetic agents. The current study aimed to evaluate the effects of propofol on the behavior of human gastric cancer cells and the molecular mechanisms of this activity. The effects of propofol on SGC7901 and AGS cell proliferation, apoptosis, and invasion were detected by MTT assay, flow cytometric analysis, and matrigel invasion assay. Real-time polymerase chain reaction (PCR) was used to assess microRNA (miR)-221 expression. miR-221 mimics were transfected into SGC7901 and AGS cells to assess the role of miR- 221 in propofol-induced anti-tumor activity. Propofol significantly inhibited cell proliferation and invasion and promoted apoptosis of SGC7901 and AGS cells. Propofol also efficiently reduced miR-221 expression. Moreover, transfection of miR-221 mimics reversed the effects of propofol on the biological behavior of gastric cancer cells. Propofol can effectively inhibit proliferation and invasion and induce apoptosis of gastric cancer cells through, at least partly, downregulation of miR-221 expression.

Antipruritic and antinociceptive effects of Chenopodium album L in mice

The ethanolic extract from the fruits of Chenopodium album L. (FCAL), orally administered at doses of 100-400 mg/kg, dose-dependently inhibited scratching behavior induced by 5-HT (10 micro g per mouse, s.c.) or compound 48/80 (50 micro g per mouse, s.c.) in mice. But it failed to affect hind paw swelling induced by 5-HT or compound 48/80 in mice at doses of 100 and 200 mg/kg and only showed a relatively weak inhibition on the swelling at a higher dose of 400 mg/kg. In addition, FCAL (200 and 400 mg/kg) significantly attenuated the writhing responses induced by an intraperitoneal injection of acetic acid and the inflammatory pain response induced by an intraplantar injection of formalin in mice. At a dose of 400 mg/kg, it also inhibited the neurogenic pain response of formalin test. In conclusion, FCAL possesses antipruritic and antinociceptive activities and the antinociceptive effects are not secondary to anti-inflammatory effects. The findings support evidence for the clinical use of FCAL to treat cutaneous pruritus.

Densification and strain hardening of a metallic glass under tension at room temperature

The deformation of metallic glasses involves two competing processes: a disordering process involving dilatation, free volume accumulation, and softening, and a relaxation process involving diffusional ordering and densification. For metallic glasses at room temperature and under uniaxial loading, disordering usually dominates, and the glass can fail catastrophically as the softening process runs away in a localized mode. Here we demonstrate conditions where the opposite, unexpected, situation occurs: the densifying process dominates, resulting in stable plastic deformation and work hardening at room temperature. We report densification and hardening during deformation in a Zr-based glass under multiaxial loading, in a notched tensile geometry. The effect is driven by stress-enhanced diffusional relaxation, and is attended by a reduction in exothermic heat and hardening signatures similar to those observed in the classical thermal relaxation of glasses. The result is significant, stable, plastic, extensional flow in metallic glasses, which suggest a possibility of designing tough glasses based on their flow properties.

A sesquiterpene lactone glucoside from Ixeris denticulata f. pinnatipartita

An extract from the entire Ixeris denticulata f. pinnatipartita plant afforded the guaianolide sesquiterpene lactone glucoside, 8 beta,15-dihydroxy-1(10),3,11(13)-guaiatrien-12,6-olide-15-O- glucopyranoside, along with the known flavonoids luteolin-7-O-glucoside and luteolin-7-O-glucuronide-6'-methyl ester; their structures were determined by spectroscopic methods. Ixerin Y inhibited the growth of human breast cancer MCF7 and MDA468 cell lines.

Identification of Dryopteris crassirhizoma and the adulterant species based on cpDNA rbcL and translated amino acid sequences

Dry rhizome of Dryopteris crassirhizoma Nakai (Dryopteridaceae), also known as Guan Zhong, is a traditional Chinese herbal medicine used in the treatment of viral disease. But the dry rhizomes of Woodwardia JAPONICA (L. f.) Sm., OSMUNDA JAPONICA Thunb. and Cyrtomium fortunei J. Sm. are also used as Guan Zhong in local areas. The adulterants are similar to Dryopteris crassirhizoma. It is difficult to identify the botanical origin of these herbs. In our study, sequences of the cpDNA RBCL gene were determined and analyzed for Dryopteris crassirhizoma and adulterant species, where nineteen molecular markers had been determined. Also, amino acid sequences translated from the RBCL gene were analyzed and four important molecular markers were detected. Based on cpDNA RBCL and translated amino acid sequences, Dryopteris crassirhizoma can easily be distinguished from the other three fern species.

Determination of Ginsenosides (Ginseng Saponins) in Dry Root Powder from Panax ginseng, Panax quinquefolius, and Selected Commercial Products by Liquid Chromatography: Interlaboratory Study

Twelve collaborating laboratories assayed 4 products, namely, Panax ginseng, Panax quinquefolius, and 2 ginseng products, for 6 ginsenosides: Rb1, Rb2, Rc, Rd, Re, andRg1. Collaborators also received a negative control for the recovery study. Pure ginsenosides were provided as reference standards for the liquid chromatography (LC) analysis and the system suitability tests. The LC analyses were performed on the methanol extract using UV detection at 203 nm. For P. ginseng, individual ginsenosides were consistent in their means; repeatability standard deviations (RSDr)rangedfrom4.17to5.09% and reproducibility standard deviations (RSDR) ranged from 7.27 to 11.3%. For P. quinquefolius, the Rb1 and Rb2 ginsenosides were higher and lower in concentration than P. ginseng, with RSDr values of 3.44 and 6.60% and RSDR values of 5.91 and 12.6% respectively, and other analytes at intermediate precisions. For ginseng commercial products, RSDr values ranged from 3.39 to 8.12%, andRSDR values ranged from 7.65 to 16.5%. A recovery study was also conducted for 3 ginsenosides: Rg1, Re, andRb1. The average recoveries were 99.9, 96.2, and 92.3%, respectively. The method is not applicable for the determination of Rg1 and Re in ginseng product at levels <300 mg/kg.

Meta-analysis demonstrates that the NAD(P)H: quinone oxidoreductase 1 (NQO1) gene 609 C>T polymorphism is associated with increased gastric cancer risk in Asians

The association between the NAD(P)H: quinone oxidoreductase 1 (NQO1) gene C609T polymorphism and gastric cancer has been widely evaluated, yet with conflicting results. Data were available from seven study populations involving 2600 subjects. Overall, comparison of alleles 609T and 609C indicated a significantly increased risk (46%) for gastric cancer (95% confidence interval (95%CI) for odds ratio (OR) = 1.20-1.79) in individuals with the T allele. The tendency was increased in the homozygous comparison (609TT versus 609CC), with an OR = 2.04 (95%CI = 1.37-3.05). Stratified analysis by study design demonstrated stronger associations in population-based studies than in hospital-based studies, based on OR. Ethnicity-based analysis demonstrated a significant association in Asians but not in Caucasians. Additionally, in the subgroup analyses by the type of gastric cancer, a significantly increased risk was found with all genetic models in the gastric adenocarcinoma subgroup compared to the others. We conclude that the NQO1 gene C609T polymorphism increases the risk for gastric cancer, especially in Asian populations.

Recent advances in pharmacognosy research in China

1. Progress made in pharmacognostic research by Chinese investigators in the last decade is summarized herein. 2. This review covers studies on herbal properties, resources, identification, physicochemical evaluation, cultivation, breeding, tissue culture, collection, processing, preparation, active principles and pharmacological activities of traditional and herbal Chinese drugs. 3. As a result of these research activities errors in species identification were spotted, new drug resources were revealed, new taxa were discovered, crude drugs were analyzed qualitatively and quantitatively, optimal conditions for cultivation and breeding of plants and animals used as drugs were formulated, the quality of some drugs was controlled, the drug processing procedures and storage conditions were evaluated, and the chemistry and pharmacology of a number of crude drugs were elucidated.

Lack of association between the interleukin 6 gene -174G>C polymorphism and colorectal cancer: evidence from a meta-analysis

Interleukin 6 (IL6) is a pleiotropic cytokine involved in physiological processes and in a variety of human malignancies. It is thus a logical candidate for being a causative factor underlying colorectal cancer (CRC). The association between the IL6 -174G>C polymorphism and CRC has been widely evaluated; yet, there is a lack of agreement between studies on the role of this polymorphism in CRC. We performed a meta-analysis to evaluate this association signal. Articles published before May 10, 2012 were included in the meta-analysis. A total of 11 populations incorporating 6481 cases and 7935 controls were included in our analysis. A random-effect model was applied irrespective of between-study heterogeneity. Data and study quality were assessed in duplicate. Overall, the association of the -174G>C polymorphism with CRC was not significant in an allelic comparison model [odds ratio (OR) = 0.99; 95% confidence interval (95%CI) = 0.90-1.09; P = 0.827], a homozygote model (OR = 0.98; 95%CI = 0.83-1.15; P = 0.805), a dominant model (OR = 0.99; 95%CI = 0.87-1.13; P = 0.906), or a recessive model (OR = 0.97; 95%CI = 0.88-1.08; P = 0.610). Furthermore, the analyses of subgroups created based on common study design, genotyping methods, and ethnicity failed to find a significant association of this polymorphism with CRC. Therefore, our results collectively suggest that the IL6 -174G>C polymorphism might not be a potential candidate for CRC risk.

Random primed polymerase chain reaction differentiates Codonopsis pilosula from different localities

DNA fingerprints distinctive among the samples from different localities in China were successfully reproduced for the Chinese herb Dangshen, the roots of CODONOPSIS PILOSULA, (Campanulaceae). Similarity index (S.I.) analysis revealed that C. PILOSULA samples from the same province generated similar DNA fingerprints, while samples of different provinces displayed different DNA fingerprints. This method may be a general and valuable tool for locality authentication of other Chinese herbal medicinal materials.