Inhibition of G protein-coupled receptor 68 using homoharringtonine attenuates chronic kidney disease-associated cardiac impairment

Chronic kidney disease (CKD) induces cardiac inflammation and fibrosis and reduces survival. We previously demonstrated that G protein-coupled receptor 68 (GPR68) promotes cardiac inflammation and fibrosis in mice with 5/6 nephrectomy (5/6Nx) and patients with CKD. However, no method of GPR68 inhibition has been found that has potential for therapeutic application. Here, we report that Cephalotaxus harringtonia var. nana extract and homoharringtonine ameliorate cardiac inflammation and fibrosis under CKD by suppressing GPR68 function. Reagents that inhibit the function of GPR68 were explored by high-throughput screening using a medicinal plant extract library (8,008 species), and we identified an extract from Cephalotaxus harringtonia var. nana as a GPR68 inhibitor that suppresses inflammatory cytokine production in a GPR68 expression-dependent manner. Consumption of the extract inhibited inflammatory cytokine expression and cardiac fibrosis and improved the decreased survival attributable to 5/6Nx. Additionally, homoharringtonine, a cephalotaxane compound characteristic of C. harringtonia, inhibited inflammatory cytokine production. Homoharringtonine administration in drinking water alleviated cardiac fibrosis and improved heart failure and survival in 5/6Nx mice. A previously unknown effect of C. harringtonia extract and homoharringtonine was revealed in which GPR68-dependent inflammation and cardiac dysfunction were suppressed. Utilizing these compounds could represent a new strategy for treating GPR68-associated diseases, including CKD.

Screening of growth inhibitors for epithelial-mesenchymal transition-induced cells by TGF-β from plant-based sources identified the active compound hydroxychavicol from Piper bitle

Epithelial-mesenchymal transition (EMT) has recently been associated with cancer invasion, metastasis, and resistance. In our previous study, we discovered nanaomycin K, a natural growth inhibitor for EMT-induced Madin Darby canine kidney (MDCK) cells, from the cultured broth of actinomycetes. However, the screening method was undeveloped, because the activity of nanaomycin K was discovered accidentally. In this study, we established a screening method by analyzing the characteristics of nanaomycin K in MDCK cells. Nanaomycin K showed the characteristic growth inhibitory activity on MDCK cells cultured under four conditions: medium containing dimethyl sulfoxide, SB431542, TGF-β, and a mixture of SB431542 and TGF-β. The activity was stronger in TGF-β-treated cells than in DMSO-treated cells. In the mixture of SB431542 and TGF-β-treated cells, the activity of nanaomycin K was suppressed. The anti-cancer agents, mitomycin C, cisplatin, and staurosporine, lacked the characteristics as that of nanaomycin K for these four treatment conditions. Since these four conditions distinguish between the effects of nanaomycin K and other anti-cancer agents in EMT-induced cells, the screening method was established. Among the 13,427 plant extracts tested, Piper betle leaf extract displayed growth inhibitory activity against EMT-induced cells. Through the purification of the extract via bio-guided fractionation, hydroxychavicol was isolated as an active compound. The cytotoxic activity of hydroxychavicol was stronger in EMT-induced MDCK cells than in control cells. However, its cytotoxic activity was suppressed in EMT-inhibited cells. Furthermore, hydroxychavicol exhibited same activity against SAS cells (human squamous cell carcinoma of the tongue). Thus, we have successfully established a screening method for growth inhibitors of EMT-induced cells and have discovered an inhibitor from plant-based sources.

Improved quantitative analysis of tenuifolin using hydrolytic continuous-flow system to build prediction models for its content based on near-infrared spectroscopy

This study used two types of analyses and statistical calculations on powdered samples of Polygala root (PR) and Senega root (SR): (1) determination of saponin content by an independently developed quantitative analysis of tenuifolin content using a flow reactor, and (2) near-infrared spectroscopy (NIR) using crude drug powders as direct samples for metabolic profiling. Furthermore, a prediction model for tenuifolin content was developed and validated using multivariate analysis based on the results of (1) and (2). The goal of this study was to develop a rapid analytical method utilizing the saponin content and explore the possibility of quality control through a wide-area survey of crude drugs using NIR spectroscopy. Consequently, various parameters and appropriate wavelengths were examined in the regression analysis, and a model with a reasonable contribution rate and prediction accuracy was successfully developed. In this case, the wavenumber contributing to the model was consistent with that of tenuifolin, confirming that this model was based on saponin content. In this series of analyses, we have succeeded in developing a model that can quickly estimate saponin content without post-processing and have demonstrated a brief way to perform quality control of crude drugs in the clinical field and on the market.

Characterization of Anti-Poliovirus Compounds Isolated from Edible Plants

Poliovirus (PV) is the causative agent of poliomyelitis and is a target of the global eradication programs of the World Health Organization (WHO). After eradication of type 2 and 3 wild-type PVs, vaccine-derived PV remains a substantial threat against the eradication as well as type 1 wild-type PV. Antivirals could serve as an effective means to suppress the outbreak; however, no anti-PV drugs have been approved at present. Here, we screened for effective anti-PV compounds in a library of edible plant extracts (a total of 6032 extracts). We found anti-PV activity in the extracts of seven different plant species. We isolated chrysophanol and vanicoside B (VCB) as the identities of the anti-PV activities of the extracts of Rheum rhaponticum and Fallopia sachalinensis, respectively. VCB targeted the host PI4KB/OSBP pathway for its anti-PV activity (EC₅₀ = 9.2 μM) with an inhibitory effect on in vitro PI4KB activity (IC₅₀ = 5.0 μM). This work offers new insights into the anti-PV activity in edible plants that may serve as potent antivirals for PV infection.

Identification of an Oligostilbene, Vaticanol B, from Dryobalanops aromatica Leaves as an Antiviral Compound against the Hepatitis C Virus

Chronic hepatitis C virus (HCV) infection can lead to liver cirrhosis and hepatocellular carcinoma. Although current medications using direct-acting antivirals (DAAs) are highly effective and well-tolerated for treating patients with chronic HCV, high prices and the existence of DAA-resistant variants hamper treatment. There is thus a need for easily accessible antivirals with different mechanisms of action. During the screening of Indonesian medicinal plants for anti-HCV activity, we found that a crude extract of Dryobalanops aromatica leaves possessed strong antiviral activity against HCV. Bioassay-guided purification identified an oligostilbene, vaticanol B, as an active compound responsible for the anti-HCV activity. Vaticanol B inhibited HCV infection in a dose-dependent manner with 50% effective and cytotoxic concentrations of 3.6 and 559.5 µg/mL, respectively (Selectivity Index: 155.4). A time-of-addition study revealed that the infectivity of HCV virions was largely lost upon vaticanol B pretreatment. Also, the addition of vaticanol B following viral entry slightly but significantly suppressed HCV replication and HCV protein expression in HCV-infected and a subgenomic HCV replicon cells. Thus, the results clearly demonstrated that vaticanol B acted mainly on the viral entry step, while acting weakly on the post-entry step as well. Furthermore, co-treatment of the HCV NS5A inhibitor daclatasvir with vaticanol B increased the anti-HCV effect. Collectively, the present study has identified a plant-derived oligostilbene, vaticanol B, as a novel anti-HCV compound.

[Determination of 11 Cannabinoids in Cannabis sativa L. by Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (LC-Q-TOF-MS)]

Eleven major cannabinoids from each subdivided tissue of drug-type and fiber-type cannabis plants were determined by means of a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS). The cannabinoids analyzed in this study were tetrahydrocannabinol acid (THCA), Δ⁹-tetrahydrocannabinol (Δ⁹-THC), cannabidiol acid (CBDA), cannabidiol (CBD), Δ⁸-tetrahydrocannabinol (Δ⁸-THC), cannabinol (CBN), cannabichromene (CBC), cannabidivarin (CBDV), cannabigerolic acid (CBGA), cannabigerol (CBG) and tetrahydrocannabivarin (THCV). As a result, THCA was detected in the bracts at 28.4 µg/mg, in the buds at 24.8 µg/mg, and in the leaves at 5.1 to 10.5 µg/mg in the drug-type cannabis plant. In addition, Δ⁹-THC, CBGA, CBN, CBG, CBC, and THCV were mainly detected in bracts, buds, and leaves. On the other hand, as for the fiber-type cannabis plant, CBDA was detected in the bracts at 27.5 µg/mg, in the buds at 10.6 µg/mg, and in the leaves at 1.5-3.3 µg/mg. In addition, Δ⁹-THCA, CBD, Δ⁹-THC, CBC, and CBG were mainly detected in bracts, buds, and leaves.

Machine Learning-Assisted Screening of Herbal Medicine Extracts as Vaccine Adjuvants

Adjuvants are important vaccine components, composed of a variety of chemical and biological materials that enhance the vaccine antigen-specific immune responses by stimulating the innate immune cells in both direct and indirect manners to produce a variety cytokines, chemokines, and growth factors. It has been developed by empirical methods for decades and considered difficult to choose a single screening method for an ideal vaccine adjuvant, due to their diverse biochemical characteristics, complex mechanisms of, and species specificity for their adjuvanticity. We therefore established a robust adjuvant screening strategy by combining multiparametric analysis of adjuvanticity in vivo and immunological profiles in vitro (such as cytokines, chemokines, and growth factor secretion) of various library compounds derived from hot-water extracts of herbal medicines, together with their diverse distribution of nano-sized physical particle properties with a machine learning algorithm. By combining multiparametric analysis with a machine learning algorithm such as rCCA, sparse-PLS, and DIABLO, we identified that human G-CSF and mouse RANTES, produced upon adjuvant stimulation in vitro, are the most robust biological parameters that can predict the adjuvanticity of various library compounds. Notably, we revealed a certain nano-sized particle population that functioned as an independent negative parameter to adjuvanticity. Finally, we proved that the two-step strategy pairing the negative and positive parameters significantly improved the efficacy of screening and a screening strategy applying principal component analysis using the identified parameters. These novel parameters we identified for adjuvant screening by machine learning with multiple biological and physical parameters may provide new insights into the future development of effective and safe adjuvants for human use.

Efficient fertilization in the cultivation of Angelica acutiloba (Siebold & Zucc.) Kitag. in Hokkaido: Effect of amount of supplied nitrogen on growth, yield, and quality of A. acutiloba

Angelica acutiloba (Siebold & Zucc.) Kitag., the source plant of the crude drug Angelicae acutilobae radix, is traditionally cultivated in western regions of Japan. Since A. acutiloba is now also grown in Hokkaido, the northernmost prefecture of the country, the cultivation method, especially the quantity of fertilizer, needs to be adapted because of the cooler climate and shorter growing period. In this study, we compared plant growth and harvest yield of A. acutiloba cultivated with different amounts of nitrogen (N) fertilizer. When plants were fertilized with 24 kg N/10 a, the aerial part was lush, and the diameter at the top of the root was about 1.3 times thicker than that in plants treated with 12 kg N/10 a. On the other hand, the weight of the harvested root grown with 24 kg N/10 a was slightly, although not significantly, less than that in plants grown with 12 kg N/10 a. In addition, we found that the content of (Z)-ligustilide, a major essential oil contained in A. acutiloba root, is affected by nitrogen application. Interestingly, it increased with increasing amounts of supplied nitrogen. However, the importance of Angelicae acutilobae radix as the crude drug is not limited to its (Z)-ligustilide content, and there are also other crucial quality features, such as having thick lateral roots, which were generated in this study with a moderate nitrogen application. We conclude that about 12 kg N/10 a is the optimal amount of nitrogen for healthy growth of A. acutiloba in Hokkaido.

Diversity of Adenostemma lavenia, multi-potential herbs, and its kaurenoic acid composition between Japan and Taiwan

Adenostemma lavenia (L.) Kuntze (Asteraceae) is widely distributed in tropical regions of East Asia, and both A. lavenia and A. madurense (DC) are distributed in Japan. In China and Taiwan, A. lavenia is used as a folk medicine for treating lung congestion, pneumonia, and hepatitis. However, neither phylogenic nor biochemical analysis of this plants has been performed to date. We have reported that the aqueous extract of Japanese A. lavenia contained high levels of ent-11α-hydroxy-15-oxo-kaur-16-en-19-oic acid (11αOH-KA; a kaurenoic acid), which is a potent anti-melanogenic compound. Comparison of chloroplast DNA sequences suggested that A. lavenia is originated from A. madurense. Analyses of kaurenoic acids revealed that Japanese A. lavenia and A. madurense contained high levels of 11αOH-KA and moderate levels of 11α,15OH-KA, while Taiwanese A. lavenia mainly contained 9,11αOH-KA. The diverse biological activities (downregulation of Tyr, tyrosinase, gene expression [anti-melanogenic] and iNOS, inducible nitric oxide synthase, gene expression [anti-inflammatory], and upregulation of HO-1, heme-oxygenase, gene expression [anti-oxidative]) were associated with 11αOH-KA and 9,11αOH-KA but not with 11α,15OH-KA. Additionally, 11αOH-KA and 9,11αOH-KA decreased Keap1 (Kelch-like ECH-associated protein 1) protein levels, which was accompanied by upregulation of protein level and transcriptional activity of Nrf2 (NF-E2-related factor-2) followed by HO-1 gene expression. 11αOH-KA and 9,11αOH-KA differ from 11α,15OH-KA in terms of the presence of a ketone (αβ-unsaturated carbonyl group, a thiol modulator) at the 15^th position; therefore, thiol moieties on the target proteins, including Keap1, may be important for the biological activities of 11αOH-KA and 9,11αOH-KA and A. lavenia extract.

Endotoxin Contamination and Reaction Interfering Substances in the Plant Extract Library

Endotoxin is an unintentional contaminant that has numerous activities and can affect various biological experiments using cells. In this study, we measured the endotoxin activity of samples from a plant extract library (PEL) and determined their degrees of contamination. Endotoxin was detected in approx. 48% (n = 139) and approx. 4% (n = 5) of field-collected and crude drug samples, respectively, and in concentrations >5.0 EU/mL in some samples. The concentrations of endotoxin that affect cells in vitro vary depending on the target cell type. Although the degree of contamination varied in the present study, it was considered to have little effect on the cell experiments. More than 150 PEL samples had problems with reaction courses or recovery rates of Limulus amoebocyte lysate (LAL) tests. In the LAL tests, using three plant extracts [Sanguisorba officinalis L. (Rosaceae), Oenothera biennis L. (Onagraceae), and Lythrum salicaria L. (Lythraceae)], the polyphenolic compounds in the plant extracts affected LAL test and their effects differed depending on the plant species. When the 16 single polyphenol compounds were added to the LAL tests, the compounds with caffeoyl and pyrogallol moieties were found to affect the LAL reaction course and recovery rate. Furthermore, none of the compounds had any effects at concentrations of 1 µM. Because the plant extracts contained analogs of various polyphenolic compounds, they were presumed to actually act synergistically. Our findings demonstrated that attention must be paid to the recovery rate and reaction process of LAL tests with samples containing polyphenolic compounds.

NMDA receptor-dependent and -independent effects of natural compounds and crude drugs on synaptic states as revealed by drebrin imaging analysis

Effective drugs that can cure cognitive impairments remain elusive. Because synaptic dysfunction has been correlated with cognitive impairments, drug development to target synaptic dysfunction is important. Recently, natural compounds and crude drugs have emerged as potential therapeutic agents for cognitive disorders. However, their effects on synaptic function remain unclear, because of lack of evaluation system with high reproducibility. We have recently developed highly reproducible in vitro high-content imaging analysis system for evaluation of synaptic function using drebrin as a marker for synaptic states. Therefore, we aimed to examine the direct effects of well-known natural compounds and crude drugs on synaptic states using this system. Rat hippocampal neurons were treated using natural compounds (nobiletin, diosgenin and tenuifolin) and crude drugs (Uncaria Hook [UH], Bezoar Bovis [BB], Coptis Rhizome [CR], Phellodendron Bark [PB] and Polygala Root [PR]). Immunocytochemical analysis was performed, and dendrite lengths and drebrin cluster densities were automatically quantified. We found that diosgenin, tenuifolin, CR, PB and PR decreased drebrin cluster densities, and the effects of PB and PR were partially dependent on N-methyl-D-aspartic acid-type glutamate receptors (NMDARs). Nobiletin and UH did not show any effects, whereas low-dose BB treatment increased drebrin cluster densities. Our results showed that diosgenin, tenuifolin, BB, CR, PB and PR appeared to directly change synaptic states. Particularly, the NMDAR dependency of PB and PR appears to affect synaptic plasticity.

One-pot discriminant LC/MS quantitative analysis of ephedrine and pseudoephedrine using Finger Masher and their distribution in the aerial stems of Ephedra plants

A discriminant LC/MS quantitative analysis of ephedrine (EP) and pseudoephedrine (PEP) in Ephedrae herba was performed. Aerial parts of three Ephedra species were separated into internodes and extracted using Finger Masher with minimum loss. The contents of EP and PEP were measured by LC/MS/MS using the multiple reaction monitoring (MRM) method. Their contents in old-year branches were lower than those current-year branches and tended to be higher in the middle part than in the tip of each branch. The content ratio of EP and PEP was reversed in some branches depending on their extent of growth. In E. sinica, the contents were low at the first internode closest to the central main stem at each branch. The contents drastically increased from the second internode and were highest at the third internode. There was a strong correlation between the internode distance and alkaloid (EP + PEP) contents. The distribution of alkaloids in one internode was examined and the results showed that the part closest to the node had the lowest contents.

Simultaneous UHPLC/MS quantitative analysis and comparison of Saposhnikoviae radix constituents in cultivated, wild and commercial products

Differences in the components of the crude drug Saposhnikoviae radix, both wild and cultivated, and the cultivation duration were examined by UHPLC/MS. As a result, there was no significant difference in composition depending on the region in China where the drug was produced. The most abundant components in all samples were prim-O-glucosylcimifugin, 4'-O-glucosyl-5-O-methylvisamminol, 3'-O-acetylhamaudol and cimifugin. The 1 year-old Saposhnikoviae radix cultivated in Japan had a low component content overall. A comparison of components according to root thickness revealed that glycosides, such as prim-O-glucosylcimifugin and 4'-O-glucosyl-5-O-methylvisamminol, were accumulated in thin roots. In a comparison of the components according to the drying temperature, a large difference was observed in the content of glycosides, and a difference was observed depending on the sugar-binding position. According to a metabolome analysis in domestic commercial products by LC/MS, a characteristic component in the cultivated product was found and its content was low in the 1 year-old sample and high in the 2 year-old sample. If the cultivation duration is prolonged up to about 6 years, the contents of the ingredients are close to those of wild products.

Characterization of a New Antienterovirus D68 Compound Purified from Avocado

One of the major challenges in development of antienterovirus (EV) drugs is in the safety of the drug. Here, we attempted to identify anti-EV compounds from an edible plant extract library and found potent antienterovirus D68 (EV-D68) activity in avocado (Persea americana). The purified identity is determined as 2R,4R-(12Z,15Z)-heneicosa-12,15-diene-1,2,4-triol, named avoenin. Avoenin shows an EC₅₀ of 2.0 μM for EV-D68 (Fermon) infection with CC₅₀ of >150 μM in RD cells by targeting the uncoating step of EV-D68 infection. Resistant mutations of EV-D68 (VP3-V24I, S173P, and S180G) to avoenin confer cross-resistance to pleconaril, an uncoating inhibitor of EV-D68. The inhibitory effect of avoenin is substantially specific to EV-D68 among the EVs. This work reveals avoenin as the identity of anti-EV-D68 activity in avocado and offers insights into development of a novel and effective strategy to overcome EV-D68 infection and its related respiratory diseases.

Leishmanicidal phenolic compounds derived from Dalbergia cultrata

Leishmaniasis is a protozoan tropical infection that is estimated to be more than 0.3 million new cases occur annually worldwide. A novel phenolic compound, cultratin A (1), was isolated as a leishmanicidal constituent from the timber of Dalbergia cultrata, along with three known neoflavanoids (2, 3, 4), two benzofurans (5, 6), and two phenolic compounds (7, 8). Their structures were determined using spectral methods. Among them, a new compound (1) and 4-(S)-methoxydalbergione (2) showed effective leishmanicidal activities (IC₅₀: 2.0 and 2.6 μM, respectively), while compound 8 showed moderate activity (IC₅₀: 11 μM). The cytotoxicity of compounds 1 and 2 was also weaker than that of the other compounds.

Quality evaluation of health foods containing licorice in the Japanese Market

Focusing on licorice, a highly used raw material in health foods, quantitative analysis of functional/medicinal components and a safety and functional evaluation was carried out for herbal medicines, health food ingredients, and so-called health foods. A functional component, glabridin, was detected in herbal medicines from Glycyrrhiza glabra and G. inflata, health food ingredients, and in commercially available health foods that contain licorice. Likewise, glycyrrhizin, a medicinal component, was detected in these sources, except in licorice oil extract. Estrogen activity in vitro was detected in some of the herbal medicines, health food ingredients, and in health foods containing licorice. In the in vivo study, liver weight in ovariectomized (OVX) mice treated with licorice oil extract was significantly higher than that in OVX and sham mice in a dose dependent manner. These results suggest that excessive intake of licorice oil extract from health foods should be avoided, even though these ingredients might be beneficial for medical use in order to maintain bone health in postmenopausal women. Measurement of hepatic cytochrome P-450 (CYP) activity, reproductive organ weight, and fat and bone mass in OVX mice was considered useful for evaluating the safety and efficacy of estrogenic health food ingredients derived from herbal medicines.

LC-MS analysis of saponins of Achyranthes root in the Japanese market

LC-MS analyses of saponin fractions of Achyranthes roots in the Japanese market revealed that there were three patterns for the saponin fraction of their water extracts, i.e., the saponins with a sugar moiety at position 28 [achyranthosides B (3), C (4) and D (5)] were the major constituents, the saponins without sugar moiety at position 28 [betavulgarosides II (10) and IV (11)] were the major constituents, and mixtures of these saponins. In a decoction prepared from the sample which contained 10 and 11 as the major saponins, their amounts were largely decreased compared with those of the water extract. As large amounts of these saponins were found in the precipitates formed by heating of the water extract, these saponins were seemed to precipitate out under heating. When hot water was used for the extraction, 3, 4 and 5 were detected even from the samples whose water extract did not contain these saponins. This was attributed to inhibition of endogenous esterase which hydrolyzes the ester linkage at position 28. When saponins were extracted with reagent grade 1-butanol, in addition to the decrease of the amounts of highly polar saponins, oxidative decarboxylation of 3 and 10 occurred resulting in formation of achyranthoside E (6) and spinacoside D (12), respectively. As these changes were not observed with HPLC grade 1-butanol, which contain not more than 5 ppm of peroxide impurities, the change was attributable to the peroxide impurities contained in the reagent grade 1-butanol.

1H NMR-based metabolomic analysis coupled with reversed-phase solid-phase extraction for sample preparation of Saposhnikovia roots and related crude drugs

¹H NMR-based metabolomics has been applied in research on food, herbal medicine, and natural products. Although excellent results were reported, samples were directly extracted with a deuterated solvent (e.g., methanol-d₄ or D₂O) in most reports. As primary metabolites account for most of the results, data for secondary metabolites are partially reflected. Consequently, secondary metabolites tend to be excluded from factor loading analysis, serving as a significant unfavorable feature of ¹H NMR-based metabolomics when investigating biologically active or functional components in natural products and health foods. Reversed-phase solid-phase extraction column (RP-SPEC) was applied for sample preparation in ¹H NMR-based metabolomics to overcome this feature. The methanol extract from Saposhnikoviae radix (SR), an important crude drug, was fractionated with RP-SPEC into 5% methanol-eluting fractions, and the remaining fraction was collected. Each fraction was subjected to ¹H NMR-based metabolomics and compared to results from conventional ¹H NMR-based metabolomics. Based on principal component analysis (PCA) and partial least squares projections to latent structures discriminant analysis (PLS-DA), the 5% methanol fraction and conventional method reflected the amount of saccharides such as sucrose on the PC1/PLS1 axes, and wild and cultivated samples were discriminated along those axes. The remaining fraction clearly distinguished SR from Peucedanum ledebourielloides root. The compounds responsible for this discrimination were deemed falcarindiol derivatives and other unidentified secondary metabolites from the s-plot on PLS-DA. The secondary metabolites from original plants were, therefore, presumed to be concentrated in the remaining fraction by RP-SPEC treatment and strongly reflected the species differences. The developed series is considered effective to perform quality evaluation of crude drugs and natural products.

Safety and Efficacy Assessment of Isoflavones from Pueraria (Kudzu) Flower Extract in Ovariectomised Mice: A Comparison with Soy Isoflavones

Numerous Foods with Function Claims that contain the extract of Pueraria flower (kudzu) isoflavones (PFI) are available in the Japanese market. These are labelled with function claims of reducing visceral fat. However, these foods have not undergone proper safety assessment such as the evaluation of their oestrogenic activity and effects on drug-metabolising enzymes (cytochrome P-450: CYP) in the liver. This study evaluated the estrogenic effect and the hepatic CYP activity and mRNA expression in normal female mice as a safety assessment of PFI (Experiment 1). In addition, the bone mineral density and visceral fat weight in ovariectomised mice (OVX) compared to soy isoflavones (SI) was evaluated to assess the efficacy of PFI (Experiment 2). OVX control fed a control diet, OVX fed a PFI diet (the recommended human intake of PFI), OVX fed a PFI20 diet (20- times the recommended PFI), OVX fed an SI diet (the recommended human intake of SI), and OVX fed an SI20 diet (20 -times the recommended intake of SI) for 28 days in Experiment 2. Body, liver, and visceral fat weights were not affected by the PFI, PFI20, SI, or SI20 diets. The hepatic CYP1A and CYP3A activities were elevated by the SI20 treatment. Ovariectomy-induced bone loss was inhibited by the SI20 treatment, but not by the PFI20 treatment. These results suggest that (1) PFI intake in human doses had no oestrogenic properties and did not affect CYP activity in the liver; (2) there was no evidence that PFI affects the amount of visceral fat in OVX mice.

Evaluation of the safety and efficacy of Glycyrrhiza uralensis root extracts produced using artificial hydroponic-field hybrid cultivation systems II: comparison of serum concentration of glycyrrhetinic acid serum concentration in mice

To evaluate the safety and efficacy of Glycyrrhiza uralensis root produced using artificial hydroponic and artificial hydroponic-field hybrid cultivation systems, we investigated the pharmacokinetics of a major metabolite of glycyrrhizin (GL), glycyrrhetinic acid (GA). Hot water extracts obtained from the roots of the artificial hydroponic-field hybrid cultivated Glycyrrhiza uralensis were orally administered at a dose of 100 mg/kg as GL in mice and, compared with a commercial crude drug, Glycyrrhizae Radix. The temporal changes in serum GA concentration was found to depend on the GL concentration of the hot-water extracts. When hot-water extracts containing relatively high GL were administered, bimodal peaks appeared. In contrast, a broad single peak was detected when a hot-water extract containing relatively low GL content was administered. These tendencies in the serum GA concentration time course were observed for all samples, regardless of their derivation. Moreover, we compared the pharmacokinetic parameters and found that the C_max and AUC_0-48 values after oral administration of the extracts from Glycyrrhiza uralensis roots produced by the artificial cultivation system are within the range of variation for the commercial crude drugs. These results suggest the possibility that roots of Glycyrrhiza uralensis cultivated by the artificial hydroponic-field hybrid cultivation system can be used in addition to currently available commercial crude drugs produced from wild plant resources.

New Mastoparan Peptides in the Venom of the Solitary Eumenine Wasp Eumenes micado

Comprehensive LC-MS and MS/MS analysis of the crude venom extract from the solitary eumenine wasp Eumenes micado revealed the component profile of this venom mostly consisted of small peptides. The major peptide components, eumenine mastoparan-EM1 (EMP-EM1: LKLMGIVKKVLGAL-NH₂) and eumenine mastoparan-EM2 (EMP-EM2: LKLLGIVKKVLGAI-NH₂), were purified and characterized by the conventional method. The sequences of these new peptides are homologous to mastoparans, the mast cell degranulating peptides from social wasp venoms; they are 14 amino acid residues in length, rich in hydrophobic and basic amino acids, and C-terminal amidated. Accordingly, these new peptides can belong to mastoparan peptides (in other words, linear cationic α-helical peptides). Indeed, the CD spectra of these new peptides showed predominantly α-helix conformation in TFE and SDS. In biological evaluation, both peptides exhibited potent antibacterial activity, moderate degranulation activity from rat peritoneal mast cells, and significant leishmanicidal activity, while they showed virtually no hemolytic activity on human or mouse erythrocytes. These results indicated that EMP-EM peptides rather strongly associated with bacterial cell membranes rather than mammalian cell membranes.

Mutagenetic and anti-allergic studies for evaluation of extracts of Coptis Rhizome produced by an artificial hydroponic system

As a part of the investigation of the safety and efficacy of the cultivated Coptis japonica rhizome extracts using an artificial hydroponic cultivation system, the mutagenetic and anti-allergic activities were evaluated. Some extracts of commercial crude drugs of Coptis sp. were also evaluated for the comparison. None of the extracts showed a significant mutagenicity in Salmonella typhimurium TA102 by the Ames tests, but all the extracts showed in S. typhimurium TA98. The extracts of the hydroponically cultivated rhizomes showed anti-allergic activities against contact hypersensitivity as well as those of commercial crude drugs of Coptis sp. These results suggested the potential of the hydroponically cultivated rhizomes as one of the alternative sources for the medicinal usage.

Characterization of UV-Sensitive Marker Constituents of Polygala Root for TLC: Applications in Quality Control of Single Crude Drug Extract Preparations

Polygala Root (the root of Polygala tenuifolia WILLDENOW; Japanese name "Onji"), a well-known crude drug, traditionally used as an expectorant and sedative, has been attracting increased interest in recent years owing to its newly found pharmacological effect related to neuroprotection. However, there is no specific method for identifying and estimating the quality of this crude drug in the Japanese Pharmacopoeia, 17th edition. Therefore, in order to develop a TLC-based simple and convenient identification method using characteristic chemical marker(s) for the drug and its extract products, UV-sensitive constituents of Polygala Root were first investigated. A total of 23 aromatic compounds were isolated and characterized. Two new compounds, namely, polygalaonjisides A (1) and B (2), were characterized as syringic acid 4-O-(2'-O-β-D-apiosyl)-β-D-glucoside and 2-O-(β-D-glucosyl)-3'-O-benzoylsucrose, respectively. Based on these phytochemical results, a TLC method focusing on three marker spots with Rf value of approximately 0.4-0.5 due to tenuifolisides A and B and 3,6'-di-O-sinapoylsucrose was proposed as a simple and convenient test to identify Polygala Root or its single-extract products on the market. The data presented in this paper could be useful in stipulating a confirmation test to identify Polygala Root.

Monitoring of glutamate-induced excitotoxicity by mitochondrial oxygen consumption

Dysfunction of mitochondrial activity is often associated with the onset and progress of neurodegenerative diseases. Membrane depolarization induced by Na⁺ influx increases intracellular Ca²⁺ levels in neurons, which upregulates mitochondrial activity. However, overlimit of Na⁺ influx and its prolonged retention ultimately cause excitotoxicity leading to neuronal cell death. To return the membrane potential to the normal level, Na⁺ /K⁺ -ATPase exchanges intracellular Na⁺ with extracellular K⁺ by consuming a large amount of ATP. This is a reason why mitochondria are important for maintaining neurons. In addition, astrocytes are thought to be important for supporting neighboring neurons by acting as energy providers and eliminators of excessive neurotransmitters. In this study, we examined the meaning of changes in the mitochondrial oxygen consumption rate (OCR) in primary mouse neuronal populations. By varying the medium constituents and using channel modulators, we found that pyruvate rather than lactate supported OCR levels and conferred on neurons resistance to glutamate-mediated excitotoxicity. Under a pyruvate-restricted condition, our OCR monitoring could detect excitotoxicity induced by glutamate at only 10 μM. The OCR monitoring also revealed the contribution of the N-methyl-D-aspartate receptor and Na⁺ /K⁺ -ATPase to the toxicity, which allowed evaluating spontaneous excitation. In addition, the OCR monitoring showed that astrocytes preferentially used glutamate, not glutamine, for a substrate of the tricarboxylic acid cycle. This mechanism may be coupled with astrocyte-dependent protection of neurons from glutamate-mediated excitotoxicity. These results suggest that OCR monitoring would provide a new powerful tool to analyze the mechanisms underlying neurotoxicity and protection against it.

Determination of (E)-ferulic acid content in the root of Angelica acutiloba: a simple chemical evaluation method for crude drug quality control

The root of Angelica acutiloba Kitagawa is an important crude drug in Kampo medicines (traditional Japanese medicine). Chemical evaluation of crude drugs is crucial to ensuring the safety and efficacy of herbal medicine; however, there is currently no chemical standard for the A. acutiloba crude drug in Japanese pharmacopoeia. (E)-ferulic acid (FA) is an important active ingredient of Angelica spp., including A. sinensis (Oliv.) Diels, and has been suggested as a marker for quality evaluation of those crude drugs. However, it has been controversial whether FA is a reliable marker constituent of A. acutiloba. To achieve effective extraction of FA from A. acutiloba, we compared three different extraction methods: alkaline hydrolysis, ethanol extraction, and hexane extraction. FA levels in these extracts were assessed using high performance liquid chromatography (HPLC), and alkaline hydrolysis was found to be the most effective. Furthermore, in the hydrolysate, FA was distinctly identified by thin layer chromatography (TLC) analysis. These results provide useful information for the quality control of the A. acutiloba crude drug.

Botanical origin and chemical constituents of commercial Saposhnikoviae radix and its related crude drugs available in Shaanxi and the surrounding regions

Saposhnikoviae radix (SR) is described in the Japanese Pharmacopoeia as a crude drug derived from the root of Saposhnikovia divaricata Schischkin (Umbelliferae). According to Flora of China, the root of Peucedanum ledebourielloides K. F. Fu is used as a regional substitute for SR. Therefore, we surveyed the botanical origin of the drug used in China, especially Shaanxi and the surrounding regions, through nucleotide sequence analysis of the internal transcribed spacer region of rDNA. As a result, several samples from Shaanxi () and Shanxi () provinces were identified as Peucedanum ledebourielloides. To prevent this substitute from being distributed as genuine SR, we developed a thin-layer chromatography analysis condition to enable a specific compound of this species to be easily detected. The specific compound was identified as xanthalin, based on 1D- and 2D-NMR and high-resolution mass spectrometry data. The established TLC conditions were as follows-extraction solvent, n-hexane; applied volume, 5 µL; chromatographic support, silica gel; developing solvent, n-hexane:ethyl acetate:acetic acid (20:10:1); developing length, 7 cm; detection, UV (365 nm); R _f value, 0.4 (blue fluorescence; xanthalin).

Construction of Prediction Models for the Transient Receptor Potential Vanilloid Subtype 1 (TRPV1)-Stimulating Activity of Ginger and Processed Ginger Based on LC-HRMS Data and PLS Regression Analyses

To construct a model formula to evaluate the thermogenetic effect of ginger (Zingiber officinale Roscoe) from the ingredient information, we established transient receptor potential vanilloid subtype 1 (TRPV1)-stimulating activity prediction models by using a partial least-squares projections to latent structures (PLS) regression analysis in which the ingredient data from liquid chromatography-high-resolution mass spectrometry (LC-HRMS) and the stimulating activity values for TRPV1 receptor were used as explanatory and objective variables, respectively. By optimizing the peak extraction condition of the LC-HRMS data and the data preprocessing parameters of the PLS regression analysis, we succeeded in the construction of a TRPV1-stimulating activity prediction model with high precision ability. We then searched for the components responsible for the TRPV1-stimulating activity by analyzing the loading plot and s-plot of the model, and we identified [6]-gingerol (1) and hexahydrocurcumin (3) as TRPV1-stimulating activity components.

Evaluation of the safety and efficacy of Glycyrrhiza uralensis root extracts produced using artificial hydroponic and artificial hydroponic-field hybrid cultivation systems

Glycyrrhiza uralensis roots used in this study were produced using novel cultivation systems, including artificial hydroponics and artificial hydroponic-field hybrid cultivation. The equivalency between G. uralensis root extracts produced by hydroponics and/or hybrid cultivation and a commercial Glycyrrhiza crude drug were evaluated for both safety and efficacy, and there were no significant differences in terms of mutagenicity on the Ames tests. The levels of cadmium and mercury in both hydroponic roots and crude drugs were less than the limit of quantitation. Arsenic levels were lower in all hydroponic roots than in the crude drug, whereas mean lead levels in the crude drug were not significantly different from those in the hydroponically cultivated G. uralensis roots. Both hydroponic and hybrid-cultivated root extracts showed antiallergic activities against contact hypersensitivity that were similar to those of the crude drug extracts. These study results suggest that hydroponic and hybrid-cultivated roots are equivalent in safety and efficacy to those of commercial crude drugs. Further studies are necessary before the roots are applicable as replacements for the currently available commercial crude drugs produced from wild plant resources.

Application of a new method, orthogonal projection to latent structure (OPLS) combined with principal component analysis (PCA), to screening of prostaglandin E2 production inhibitory flavonoids in Scutellaria Root

A new method consisting of orthogonal projection to latent structure (OPLS) and modified principal component analysis (PCA) was applied to a screening of bioactive compounds from natural products. In this report, extracts of 52 Scutellaria Root (the root of Scutellaria baicalensis Georgi) samples were analyzed by high-performance liquid chromatography (HPLC), and their inhibitory activities towards prostaglandin E2 (PGE2) production in a murine macrophage-like cell line J774.1 were examined. Wogonin and oroxylin A were predicted to be strong inhibitors of PGE2 production by OPLS analysis of the data. However, 6-methoxywogonin, which has been reported to have inhibitory activity, was omitted. Modified PCA was then applied to these data as a filter to exclude compounds less relevant to the activity, and OPLS analysis was applied to the modified data. As a result, this method predicted wogonin, oroxylin A and 6-methoxywogonin to be strong inhibitors of PGE2 production without any prior knowledge. The predictions by the OPLS combined with PCA method of PGE2 production inhibitory activities of 52 samples showed good agreement with the actual data. This method is simple and effective and can be used in screening of bioactive natural compounds without any prior knowledge.

Pterosin B prevents chondrocyte hypertrophy and osteoarthritis in mice by inhibiting Sik3

Osteoarthritis is a common debilitating joint disorder. Risk factors for osteoarthritis include age, which is associated with thinning of articular cartilage. Here we generate chondrocyte-specific salt-inducible kinase 3 (Sik3) conditional knockout mice that are resistant to osteoarthritis with thickened articular cartilage owing to a larger chondrocyte population. We also identify an edible Pteridium aquilinum compound, pterosin B, as a Sik3 pathway inhibitor. We show that either Sik3 deletion or intraarticular injection of mice with pterosin B inhibits chondrocyte hypertrophy and protects cartilage from osteoarthritis. Collectively, our results suggest Sik3 regulates the homeostasis of articular cartilage and is a target for the treatment of osteoarthritis, with pterosin B as a candidate therapeutic.

LC-MS-based quantification method for Achyranthes root saponins

A liquid chromatography mass spectrometry (LC-MS) method was developed for simultaneous quantitative analysis of Achyranthes root saponins: chikusetsusaponins IVa (1) and V (2), achyranthosides B (3), C (4), D (5), E (6), and G (7), sulfachyranthosides B (8) and D (9), and betavulgarosides II (10) and IV (11). Satisfactory separation of the saponins was achieved with the use of a volatile ion-pair reagent (dihexyl ammonium acetate) on a phenyl-hexylated silica gel column, and the amounts of saponins extracted under three different conditions were determined. When Achyranthes root was extracted with water at room temperature, achyranthosides B (3) and D (5) were the major saponins, and smaller amounts of other saponins (4, 6-11) were present. However, the amounts of chikusetsusaponins (1 and 2) were negligible. Under the condition to make a standard decoction of a Kampo formula, the major saponins were achyranthosides B (3), C (4), and D (5), and small amounts of chikusetsusaponins IVa (1) and V (2) appeared, whereas prolonged heating largely increased the amounts of chikusetsusaponins. This method can be used for quality control of Achyranthes root.

Salt-inducible Kinase 3 Signaling Is Important for the Gluconeogenic Programs in Mouse Hepatocytes

Salt-inducible kinases (SIKs), members of the 5'-AMP-activated protein kinase (AMPK) family, are proposed to be important suppressors of gluconeogenic programs in the liver via the phosphorylation-dependent inactivation of the CREB-specific coactivator CRTC2. Although a dramatic phenotype for glucose metabolism has been found in SIK3-KO mice, additional complex phenotypes, dysregulation of bile acids, cholesterol, and fat homeostasis can render it difficult to discuss the hepatic functions of SIK3. The aim of this study was to examine the cell autonomous actions of SIK3 in hepatocytes. To eliminate systemic effects, we prepared primary hepatocytes and screened the small compounds suppressing SIK3 signaling cascades. SIK3-KO primary hepatocytes produced glucose more quickly after treatment with the cAMP agonist forskolin than the WT hepatocytes, which was accompanied by enhanced gluconeogenic gene expression and CRTC2 dephosphorylation. Reporter-based screening identified pterosin B as a SIK3 signaling-specific inhibitor. Pterosin B suppressed SIK3 downstream cascades by up-regulating the phosphorylation levels in the SIK3 C-terminal regulatory domain. When pterosin B promoted glucose production by up-regulating gluconeogenic gene expression in mouse hepatoma AML-12 cells, it decreased the glycogen content and stimulated an association between the glycogen phosphorylase kinase gamma subunit (PHKG2) and SIK3. PHKG2 phosphorylated the peptides with sequences of the C-terminal domain of SIK3. Here we found that the levels of active AMPK were higher both in the SIK3-KO hepatocytes and in pterosin B-treated AML-12 cells than in their controls. These results suggest that SIK3, rather than SIK1, SIK2, or AMPKs, acts as the predominant suppressor in gluconeogenic gene expression in the hepatocytes.

Salt-inducible kinase 3 deficiency exacerbates lipopolysaccharide-induced endotoxin shock accompanied by increased levels of pro-inflammatory molecules in mice

Macrophages play important roles in the innate immune system during infection and systemic inflammation. When bacterial lipopolysaccharide (LPS) binds to Toll-like receptor 4 on macrophages, several signalling cascades co-operatively up-regulate gene expression of inflammatory molecules. The present study aimed to examine whether salt-inducible kinase [SIK, a member of the AMP-activated protein kinase (AMPK) family] could contribute to the regulation of immune signal not only in cultured macrophages, but also in vivo. LPS up-regulated SIK3 expression in murine RAW264.7 macrophages and exogenously over-expressed SIK3 negatively regulated the expression of inflammatory molecules [interleukin-6 (IL-6), nitric oxide (NO) and IL-12p40] in RAW264.7 macrophages. Conversely, these inflammatory molecule levels were up-regulated in SIK3-deficient thioglycollate-elicited peritoneal macrophages (TEPM), despite no impairment of the classical signalling cascades. Forced expression of SIK3 in SIK3-deficient TEPM suppressed the levels of the above-mentioned inflammatory molecules. LPS injection (10 mg/kg) led to the death of all SIK3-knockout (KO) mice within 48 hr after treatment, whereas only one mouse died in the SIK1-KO (n = 8), SIK2-KO (n = 9) and wild-type (n = 8 or 9) groups. In addition, SIK3-KO bone marrow transplantation increased LPS sensitivity of the recipient wild-type mice, which was accompanied by an increased level of circulating IL-6. These results suggest that SIK3 is a unique negative regulator that suppresses inflammatory molecule gene expression in LPS-stimulated macrophages.

Anti-hepatitis C virus compounds obtained from Glycyrrhiza uralensis and other Glycyrrhiza species

Development of complementary and/or alternative drugs for treatment of hepatitis C virus (HCV) infection is still much needed from clinical and economic points of view. Antiviral substances obtained from medicinal plants are potentially good targets to study. Glycyrrhiza uralensis and G. glabra have been commonly used in both traditional and modern medicine. In this study, extracts of G. uralensis roots and their components were examined for anti‐HCV activity using an HCV cell culture system. It was found that a methanol extract of G. uralensis roots and its chloroform fraction possess anti‐HCV activity with 50%‐inhibitory concentrations (IC₅₀) of 20.0 and 8.0 μg/mL, respectively. Through bioactivity‐guided purification and structural analysis, glycycoumarin, glycyrin, glycyrol and liquiritigenin were isolated and identified as anti‐HCV compounds, their IC₅₀ being 8.8, 7.2, 4.6 and 16.4 μg/mL, respectively. However, glycyrrhizin, the major constituent of G. uralensis, and its monoammonium salt, showed only marginal anti‐HCV activity. It was also found that licochalcone A and glabridin, known to be exclusive constituents of G. inflata and G. glabra, respectively, did have anti‐HCV activity, their IC₅₀ being 2.5 and 6.2 μg/mL, respectively. Another chalcone, isoliquiritigenin, also showed anti‐HCV activity, with an IC₅₀ of 3.7 μg/mL. Time‐of‐addition analysis revealed that all Glycyrrhiza‐derived anti‐HCV compounds tested in this study act at the post‐entry step. In conclusion, the present results suggest that glycycoumarin, glycyrin, glycyrol and liquiritigenin isolated from G. uralensis, as well as isoliquiritigenin, licochalcone A and glabridin, would be good candidates for seed compounds to develop antivirals against HCV.

Antiviral activities of Indonesian medicinal plants in the East Java region against hepatitis C virus

Background

Hepatitis C virus (HCV) is a major cause of liver disease and a potential cause of substantial morbidity and mortality worldwide. The overall prevalence of HCV infection is 2%, representing 120 million people worldwide. Current standard treatment using pegylated interferon and ribavirin is effective in only 50% of the patients infected with HCV genotype 1, and is associated with significant side effects. Therefore, it is still of importance to develop new drugs for treatment of HCV. Antiviral substances obtained from natural products, including medicinal plants, are potentially good targets to study. In this study, we evaluated Indonesian medicinal plants for their anti-HCV activities.

Methods

Ethanol extracts of 21 samples derived from 17 species of medicinal plants explored in the East Java region were tested. Anti-HCV activities were determined by a cell culture method using Huh7.5 cells and HCV strains of 9 different genotypes (1a to 7a, 1b and 2b).

Results

Four of the 21 samples tested showed antiviral activities against HCV: Toona sureni leaves (TSL) with 50% inhibitory concentrations (IC₅₀) of 13.9 and 2.0 μg/ml against the HCV J6/JFH1-P47 and -P1 strains, respectively, Melicope latifolia leaves (MLL) with IC₅₀ of 3.5 and 2.1 μg/ml, respectively, Melanolepis multiglandulosa stem (MMS) with IC₅₀ of 17.1 and 6.2 μg/ml, respectively, and Ficus fistulosa leaves (FFL) with IC₅₀ of 15.0 and 5.7 μg/ml, respectively. Time-of-addition experiments revealed that TSL and MLL inhibited both at the entry and post-entry steps while MMS and FFL principally at the entry step. TSL and MLL inhibited all of 11 HCV strains of all the genotypes tested to the same extent. On the other hand, FFL showed significantly weaker inhibitory activities against the HCV genotype 1a strain, and MMS against the HCV strains of genotypes 2b and 7a to a lesser extent, compared to the other HCV genotypes.

Conclusions

Ethanol extracts of TSL, MLL, MMS and FFL showed antiviral activities against all the HCV genotypes tested with the exception that some genotype(s) showed significant resistance to FFL and to MMS to a lesser extent. These plant extracts may be good candidates for the development of anti-HCV drugs.

Leishmanicidal active withanolides from a pakistani medicinal plant, Withania coagulans

In the course of screening for leishmanicidal constituents from Asian and South American medicinal plants, a Pakistani medicinal plant, Withania coagulans, showed activity. We therefore studied the active components of the methanol extract of aerial parts of W. coagulans. From the ethyl acetate soluble fraction of the extract, four new withanolides (1-4) were isolated along with seven known withanolides (5-11). The new compounds were elucidated to be (14R,15R,17S,20S,22R)-14,15,17,20-tetrahydroxy-1-oxowitha-2,5,24-trienolide (1), (14R,15R,17S,20S,22R)-14,15,17,20-tetrahydroxy-1-oxowitha-3,5,24-trienolide (2), (14S,17R,20S,22R)-14,17,20-trihydroxy-1-oxowitha-2,5,24-trienolide (3), and (14S,17R,20S,22R)-14,17,20-trihydroxy-1-oxowitha-3,5,24-trienolide (4), from 1H-NMR, 13C-NMR, 2D-NMR and high resolution (HR)-MS data. Some of these compounds having the partial structure 1-oxo-2,5-diene showed strong leishmanicidal activity against Leishmania major.

Leishmanicidal activities and cytotoxicities of bisnaphthoquinone analogues and naphthol derivatives from Burman Diospyros burmanica

A methanol extract of the wood of Diospyros burmanica, collected in Burma (Myanmar), was found to exhibit significant activity against Leishmania major. Subsequent chromatographically resolved fractionation led to the isolation of three novel bisnaphthoquinone analogues, burmanin A, B, and C (1-3), together with nine known compounds (4-12). The structure of 1 was confirmed by X-ray crystallography, and those of 2 and 3 by spectroscopic techniques, including 1D and 2D NMR. The inhibitory activities of the isolates were evaluated against the promastigote forms of Leishmania major and the murine macrophage-like cell line, RAW264.7.

In vitro leishmanicidal activity of benzophenanthridine alkaloids from Bocconia pearcei and related compounds

Leishmanicidal activities of benzophenanthridine alkaloids isolated from fruits of Bocconia pearcei and their derivatives were examined. Seven benzophenanthridine compounds were isolated from the methanolic extracts of B. pearcei. Among them, dihydrosanguinarine showed the most potent leishmanicidal activities (IC(50) value: 0.014 microg/ml, respectively). To examine the structure-activity relationship of the benzophenanthridine skeleton, the leishmanicidal activities for 32 synthetic samples were examined. The existence of bulky groups at the C(7)-C(8) position was found to enhance the activity. On the other hand, the bulkiness at the C(2)-C(3) position on the D-ring, a carbonyl group at C-6, substitution at C-6 and cleavage or saturation of the C(5)-C(6) bond reduced activity. A methyl group on nitrogen of the C-ring was thought to be necessary for significant activity.