Silibinin Capsules improves high fat diet-induced nonalcoholic fatty liver disease in hamsters through modifying hepatic de novo lipogenesis and fatty acid oxidation.

ETHNOPHARMACOLOGICAL RELEVANCE: Silibinin Capsules (SC) is a silybin-phospholipid complex with silybin as the bioactive component. Silybin accounts for 50-70% of the seed extract of Silybum marianum (L.) Gaertn.. As a traditional medicine, silybin has been used for treatment of liver diseases and is known to provide a wide range of hepatoprotective effects. AIM OF THE STUDY: High fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) is a worldwide health problem. This study was to investigate the role of SC in NAFLD with focusing on its underlying mechanism and likely target. MATERIALS AND METHODS: Male hamsters (Cricetidae) received HFD for 10 weeks to establish NAFLD model. NAFLD was assessed by biochemical assays, histology and immunohistochemistry. Proton nuclear magnetic resonance spectroscopy and western blot were conducted to gain insight into the mechanism. RESULTS: Hamsters fed HFD for 10 weeks developed fatty liver accompanying with increased triglyceride (TG) accumulation, enhancing de novo lipogenesis, increase in fatty acid (FA) uptake and reducing FA oxidation and TG lipolysis, as well as a decrease in the expression of phospho-adenosine monophosphate activated protein kinase α (p-AMPKα) and Sirt 1. SC treatment at 50mg/kg silybin and 100mg/kg silybin for 8 weeks protected hamsters from development of fatty liver, reducing de novo lipogenesis and increasing FA oxidation and p-AMPKα expression, while having no effect on FA uptake and TG lipolysis. CONCLUSIONS: SC protected against NAFLD in hamsters by inhibition of de novo lipogenesis and promotion of FA oxidation, which was likely mediated by activation of AMPKα.

Discovery of selective, orally bioavailable, N-linked arylsulfonamide Nav1.7 inhibitors with pain efficacy in mice.

The voltage-gated sodium channel Nav1.7 is a genetically validated target for the treatment of pain with gain-of-function mutations in man eliciting a variety of painful disorders and loss-of-function mutations affording insensitivity to pain. Unfortunately, drugs thought to garner efficacy via Nav1 inhibition have undesirable side effect profiles due to their lack of selectivity over channel isoforms. Herein we report the discovery of a novel series of orally bioavailable arylsulfonamide Nav1.7 inhibitors with high levels of selectivity over Nav1.5, the Nav isoform responsible for cardiovascular side effects, through judicious use of parallel medicinal chemistry and physicochemical property optimization. This effort produced inhibitors such as compound 5 with excellent potency, selectivity, behavioral efficacy in a rodent pain model, and efficacy in a mouse itch model suggestive of target modulation.

Chemical constituents of the stem bark of Morus cathayana.

Phytochemical investigation of the stem bark of Morus cathayana led to the isolation and identification of six new compounds, cathayanons F-J (1-5) and cathayanin A (6), and two known compounds, cathayanins B-C (7-8). Their structures were elucidated by spectroscopic methods. Compounds 1, 2, 3, 5, and 7 exhibited weak activities against five human cancer cell lines, with IC(50) values ranging from 4.7 to 9.8 microg/ml.

Three new Diels-Alder type adducts from the stem bark of Morus cathayana.

Three new Diels-Alder type adducts cathayanons C (1), D (2), and E (3), together with one known compound sanggenon C (4), were isolated from the stem bark of Morus cathayana. Their structures were fully elucidated by spectroscopic and chemical methods. Compound 2 showed good anti-oxidation activity with the inhibitory rate of malondialdehyde being 88% at a concentration of 10(- 6) mol/l.

Jacaranone analogs from Senecio scandens.

Bioassay-guided fractionation of the ethanolic extract of Senecio scandens led to the isolation of four new compounds 4, 5, 7, and 8, along with four known jacaranone analogs (1, 2, 3, 6). Their structures were elucidated on the basis of spectral and chemical evidence. Compound 7 was obtained as a tautomeric mixture of alpha/beta-epimer. The cytotoxic activities of these compounds were evaluated. Among these, compounds 5 and 8 showed potent cytotoxicities. The benzoquinone derivative, jacaranone ethyl ester (1), was the major cytotoxic constituent in this plant with IC(50)s at a range of 0.5-1.0 microg/ml against various tumor cell lines. The SAR of these jacaranone analogs (1-8), isolated from S. scandens, was also discussed.

[Identification of dihydroflavonol glycoside isomers in Smilax glabra by HPLC-MS and HPLC-1H NMR].

OBJECTIVE: To identify dihydroflavonol glycoside isomers in Smilax glabra. METHOD: The sample was analyzed by HPLC-MS in combination with HPLC-1H-NMR. RESULT: Four dihydroflavonol glycoside isomers were identified as astilbin, neoastilbin, isoastilbin, neoisoastilbin. CONCLUSION: The method is simple and rapid for the identification of dihydroflavonol glycosides in S. glabra.

Structural characterization of constituents with molecular diversity in fractions from Lysidice brevicalyx by liquid chromatography/diode-array detection/electrospray ionization tandem mass spectrometry and liquid chromatography/nuclear magnetic resonance.

A combination of electrospray ionization tandem mass spectrometry with high-performance liquid chromatography (HPLC/ESI-MSn), and hyphenation of liquid chromatography to nuclear magnetic resonance spectroscopy (HPLC/NMR), have been extensively utilized for on-line analysis of natural products, analyzing metabolite and drug impurity. In our last paper, we reported an on-line analytical method for structural identification of trace alkaloids in the same class. However, the structural types of the constituents in plants were various, such as flavanoids, terpenoids and steroids. It is important to establish an effective analytical method for on-line structural identification of constituents with molecular diversity in extracts of plants. So, in the present study, the fragmentation patterns of some isolated stilbenes, phloroglucinols and flavanoids from Lysidice rhodostegia were investigated by ESI-MSn. Their fragmentation rules and UV characteristics are summarized, and the relationship between the spectral characteristics, rules and the structures is described. According to the fragmentation rules, NMR and UV spectral characteristics, 24 constituents of different types in the fractions from L. brevicalyx of the same genus were structurally characterized on the basis of HPLC/HRMS, HPLC-UV/ESI-MSn, HPLC/1H NMR and HPLC/1H-1H COSY rapidly. Of these, six (10, 13, 14, 16, 17 and 23) are new compounds and all of them are reported from L. brevicalyx for the first time. The aim is to develop an effective analytical method for on-line structural identification of natural products with molecular diversity in plants, and to guide the rapid and direct isolation of novel compounds by chemical screening.

Rapid structural determination of new trace cassaine-type diterpenoid amides in fractions from Erythrophleum fordii by liquid chromatography-diode-array detection/electrospray ionization tandem mass spectrometry and liquid chromatography/nuclear magnetic resonance.

Electrospray ionization multi-stage tandem mass spectrometry (ESI-MSn), and combination with HPLC (HPLC/ESI-MSn), have been extensively applied to on-line analysis of natural products. Hyphenation of liquid chromatography to nuclear magnetic resonance spectroscopy (HPLC/NMR) has been developed in the last decade, which is utilized for the analysis of metabolites and drug impurities. In the study reported here, the fragmentation behaviors of eight cassaine-type diterpenoid amides from Erythrophleum fordii were investigated by ESI-MSn. The fragmentation rules and NMR spectral characteristics are summarized, and the relationship among the rules, characteristics and the structures is described. According to the fragmentation rules and NMR spectral characteristics, seven trace constituents and two formerly obtained compounds of cassaine-type diterpenoid amides in the fractions from E. fordii were structurally characterized on the basis of HPLC/HRMS, HPLC-DAD/ESI-MSn, HPLC/1H NMR and HPLC/1H-1H COSY rapidly. Among them, constituents 1-5 are new compounds, and 6 and 7 are reported from E. fordii for the first time. The aim is to develop an effective analytical method for structural identification of new trace natural products in plants.

[Studies on chemical constituents from roots of Cudrania cochinchinensis].

OBJECTIVE: To study the chemical constituents from the roots of Cudrania cochinchinensis. METHOD: The chemical constituents of C. cochinchinensis were isolated and purified by silica gel, polyamide column chromatography, Their structures were identified on the basis of spectroscopic data. RESULT: Six compounds were isolated and identified. Their structures were established as 3, 5, 7, 4"-tetrahydroxyflavanone-7-O-(6"-acetyl)-glucoside (1), 3, 5, 7, 4'-tetra hydroxyflavanone-7-O-glucoside (2), 2', 4', 5, 7-tetrahydroxy-6-prenyldihydroflavanone (3), 5, 7, 4'-trihysdroxy-6-prenylisoflavanone (4), 1, 3, 5, 6-tetrahydroxyxanthone (5), stilbene-2, 4, 3', 5'-tetraol (6). CONCLUSION: Compound 1 was isolated from this genus, while compounds 4 and 5 were isolated from this plant for the first time.

Two novel tetrairidoid glucosides from Dipsacus asper.

[reaction: see text] Two new iridoid glucoside tetramers, dipsanosides A (1) and B (2), the first-reported iridoid tetramers with four glucosides, were isolated from Dipsacus asper. Their structures were determined by analysis of 1D and 2D NMR data as well as by comparison with model compounds. Their cytotoxicities were tested, but neither of them showed obvious activity.

Acetylated flavonol diglucosides from Meconopsis quintuplinervia.

Four acetylated flavonol diglucosides, quercetin 3-O-[2'''-O-acetyl-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranoside], quercetin 3-O-[2''',6'''-O-diacetyl-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranoside], isorhamnetin 3-O-[2'''-O-acetyl-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranoside], and quercetin 3-O-[2'''-O-acetyl-alpha-l-arabinopyranosyl-(1-->6)-beta-d-glucopyranoside], together with five known flavonol glycosides quercetin 3-O-beta-d-glucopyranoside, kaempferol 3-O-beta-d-glucopyranoside, quercetin 3-O-[beta-d-galactopyranosyl-(1-->6)-glucopyranoside], isorhamnetin 3-O-[beta-d-galactopyranosyl-(1-->6)-beta-d-glucopyranoside], and kaempferol 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucopyranoside] have been isolated from Meconopsis quintuplinervia. Their structures were determined using chemical and spectroscopic methods including HRFABMS, (1)H-(1)H COSY, HSQC and HMBC experiments.

[Chemical constitutents of Bauhinia aurea].

OBJECTIVE: To study the chemical constituents of Bauhinia aurea. METHOD: The compounds were isolated with column chromatography. The structures were determined by MS and NMR spectroscopic techniques. RESULT: Nine aromatic acid derivatives, two triterpenes and three steroids were isolated from the 90% ethanolic extract and their structures were identified as 3,4-di-hydroxybenzoic acid (1), 4-hydroxybenzoic acid (2), 3-hydroxy-4-methoxy-benzoic acid (3), 4-hydroxy-3-methoxybenzoic acid (4) , gallic acid (5) , methyl gallate (6) , ethyl gallate (7) , lupeol (8) , lupenone (9) , stigmast4-en-3-one (10) beta-sitosterol (11) and daucosterol (12). CONCLUSION: This is the first report of chemical constituents from B. aurea. Compounds were isolated from this genus for the first time, except 5,8,11 and 12.

Iridoid glycosides and grayanane diterpenoids from the roots of Craibiodendron henryi.

Four new iridoid glycosides, 10-O-trans-p-coumaroylscandoside (1), 10-O-cis-p-coumaroylscandoside (2), 10-O-trans-p-coumaroyldesacetyl asperulosidic acid (3), and 10-O-cis-p-coumaroyldesacetyl asperulosidic acid (4), and two new grayanane diterpenoids, 14beta-O-(2S,3S-nilyl)-2alpha,3beta,5beta,6beta,16alpha-pentahydroxygrayanane (5) and 14beta-O-(2S,3S-nilyl)-2alpha,3beta,5beta,6beta,16alpha-pentahydroxygrayan-10(20)-ene (6), have been isolated from Craibiodendron henryi. The structures of these compounds were determined by chemical and spectroscopic methods including 1H-1H COSY, HMQC, HMBC, and NOESY experiments. Antioxidant activities and vasodilator effects of these compounds were assessed.

Anthraquinones from the roots of Prismatomeris tetrandra.

Three new anthraquinones, 1-hydroxy-2,3-dimethoxy-7-methyl-9,10-anthraquinone, 1,3-dihydroxy-5,6-dimethoxy-2-methyl-9,10-anthraquinone, and 3-hydroxy-1,5,6-trimethoxy-2-methyl-9,10-anthraquinone, along with five known anthraquinones were isolated from the roots of Prismatomeris tetrandra. Their structures were determined on the basis of spectroscopic data.

Five new cytotoxic triterpenoid saponins from the roots of Symplocos chinensis.

Five new triterpenoid saponins, named symplocososides G-K, were isolated from the roots of Symplocos chinensis. Their structures were elucidated by spectral and chemical methods as symplocososide G, 3beta-O-{[beta- D-glucopyranosyl(1-->2)][alpha-L-arabinofuranosyl(1-->4)]-beta-D-(3-O-acetyl)-glucuronopyranosyl}-21beta- O-[(2 Z)-3,7-dimethyl-2,6-octadienoyl]-22 alpha-O-(2-methylbutanoyl)-R1-barrigenol, symplocososide H, 3beta-O-{[beta-D-glucopyranosyl(1-->2)][alpha-L-arabinofuranosyl(1-->4)]- beta-D-(3-O-acetyl)-glucuronopyranosyl}-21beta-O-[(2E)3,7-dimethyl-2,6-octadienoyl]-22alpha-O-(2-methylbutanoyl)-R1-barrigenol, symplocososide I, 3beta-O-{[beta-D-glucopyranosyl(1-->2)][ alpha-L-arabinofuranosyl(1-->4)]-beta-D-(3- O-acetyl-6-O-methyl)-glucuronopyranosyl}-21beta-O-[(2 Z)3,7-dimethyl-2,6-octadienoyl]-22alpha-O-(2-methylbutanoyl)-R1-barrigenol, symplocososide J, 3 beta-O-{[ beta-D-glucopyranosyl(1-->2)][alpha-L-arabinofuranosyl(1-->4)]-beta-D-(3- O-acetyl)-glucuronopyranosyl}-21beta-O-[(2 Z)3,7-dimethyl-2,6-octadienoyl]-22alpha-O-benzoyl-R1-barrigenol, and symplocososide K, 3beta-O-{[beta-D-glucopyranosyl (1-->2)][alpha-L-arabinofuranosyl(1-->4)]- beta-D-(3-O-acetyl-6-O-methyl)-glucuronopyranosyl}-21beta-O-[(2Z)3,7-dimethyl-2,6-octadienoyl]-22alpha-O-benzoyl-R1-barrigenol. Symplocososides G-K showed significant cytotoxicity against cancer cell lines KB, HCT-8, Bel-7402, BGC-823 and A549 with IC50 values ranging from 0.82 microM to 5.09 microM, except for symplocososide I against cancer cell lines KB, BGC-823, A549 and symplocososide K against cancer cell line BGC-823 with IC50 values >10.00 microM.

The chemical constituents of Rhododendron ovatum Planch.

AIM: To study the chemical constituents of Rhododendron ovatum Planch. METHODS: The chemical constituents were isolated and purified by silica gel column chromatography and identified on the basis of their physiochemical and spectral data. RESULTS: Seven compounds were isolated and identified. Their structures were established as 3,5,7-trihydroxylchromone 3-O-beta-D-xylopyranoside (I), taraxerol (II), beta-sitosterol (III), betulinic acid (IV), quercetin (V), quercetin-3-O-alpha-L-rhamnopyranoside (VI), and D-glucose (VII). CONCLUSION: Compound I is a new compound. Compounds II-VII were isolated from this plant for the first time.

Differential mechanism-based inhibition of CYP3A4 and CYP3A5 by verapamil.

The genetic basis for polymorphic expression of CYP3A5 has been recently identified, but the significance of CYP3A5 expression is unclear. The purpose of this study is to quantify the capability of verapamil, a mechanism-based inhibitor of CYP3A, and its metabolites to inhibit the activities of CYP3A4 and CYP3A5, and to determine whether CYP3A5 expression in human liver microsomes alters the inhibitory potency of verapamil. Testosterone 6beta-hydroxylation or midazolam 1'-hydroxylation was used to quantify CYP3A activity. The possibility that verapamil and its metabolites form metabolic-intermediate complex (MIC) with CYP3A was assessed using dual beam spectrophotometry. Verapamil and N-desalkylverapamil (D617) were found to have little inhibitory effect on cDNA-expressed CYP3A5 activity and did not form a MIC with cDNA-expressed CYP3A5 as indicated by the appearance of the characteristic peak at 455 nm. At 50 microM, norverapamil showed time-dependent inhibition of CYP3A5 (30%), but to a much lesser extent compared with that of CYP3A4 (80%). The estimated values of the inactivation parameters k(inact) and K(I) of norverapamil were 4.53 microM and 0.07 min(-1) for cDNA-expressed CYP3A5, and 10.3 microM and 0.30 min(-1) for cDNA-expressed CYP3A4. Human liver microsomes that expressed CYP3A5 were less inhibited by both verapamil and norverapamil. The inactivation efficiency of verapamil and norverapamil was 30 times and 45 times lower, respectively, for CYP3A5-expressing microsomes compared with CYP3A5-non-expressing microsomes. These findings indicate that the presence of variable CYP3A5/CYP3A4 expression in the liver may contribute to the interindividual variability associated with verapamil-mediated drug interactions.

Stilbene derivatives from Gnetum cleistostachyum.

Three new stilbene derivatives, named gnetucleistol A (1), B (2) and C (3), together with four known compounds, gnetifolin A (4), p-hydroxycinnamic acid (5), piceatannol (6) and resveratrol (7), were isolated from Gnetum cleistostachyum C.Y. Cheng (Gnetaceae). Their structures were elucidated on the basis of spectroscopic evidence (EI-MS, UV, IR, NOE, 1H, 13C and 2D NMR).

Steroids from the roots of Cynanchum stauntonii.

A chemical investigation of the roots of Cynanchum stauntonii has resulted in the characterization of a new hydroperoxide with a 13,14 : 14,15-disecopregnane-type skeleton, named stauntonine (1), together with three related compounds, anhydrohirundigenin (2), anhydrohirundigenin monothevetoside (3), and glaucogenin-C mono- D-thevetoside (4). Their structures were established by spectroscopic methods, including X-ray crystallographic diffraction analysis of stauntonine that confirmed its relative stereochemistry. The compound 1 showed dose-dependent relaxation on aortic rings with endothelium contracted by phenylepherine or KCl.

New Diels-Alder type adducts from Morus macroura and their anti-oxidant activities.

Fractionation of the ethanolic extract of the stem bark of Morus macroura resulted in the isolation of four new Diels-Alder type adducts, named guangsangons K--N (1, 2, 5, 6), together with two known compounds, mulberrofuran G (3) and K (4). Their structures were determined on the basis of spectroscopic analyses and chemical methods. Furthermore, by means of (1)H-NMR variable temperature experiments and the Cotton curves in the circular dichroism (CD) spectra, the stereochemistry of four new compounds was elucidated. The isolated new compounds showed good activity on anti-oxidant in vitro, with the inhibitory rates of MDA being from 91.8 to 100.0% at concentrations of 10(-5) mol/l.