LC-MS guided isolation of sinodamines A and B: Chimonanthine-type alkaloids from the endangered ornamental plant Sinocalycanthus chinensis.

Two previously undescribed chimonanthine-type [sinodamines A and B] and five related known dimeric tryptamine-derived alkaloids were isolated and characterized from the leaves of the endangered ornamental plant Sinocalycanthus chinensis under the guidance of LC-MS detection and dereplication analyses, along with conventional isolation procedures. Their structures were established on the basis of spectroscopic methods and chemical transformations. Sinodamine A can be regarded as the naturally occurring N-oxide derivative of its pseudo-mesomer sinodamine B. An acid-catalyzed Meisenheimer rearrangement from sinodamine A to its oxazine-form with a final equilibrium of 1:2 was observed by monitoring their NMR spectra. (-)-Folicanthine showed significant cytotoxicity against human lung carcinoma A549 and colorectal carcinoma HT29 cells, with IC50 values of 7.76 and 6.16 µM, respectively.

Biginkgosides A-I, Unexpected Minor Dimeric Flavonol Diglycosidic Truxinate and Truxillate Esters from Ginkgo biloba Leaves and Their Antineuroinflammatory and Neuroprotective Activities.

Nine unexpected new flavonol glycoside cyclodimers in the truxinate (1-7, biginkgosides A-G, respectively) or truxillate [biginkgosides H (8) and I (9)] forms were isolated as minor components from the extract of Ginkgo biloba leaves. The new dimers possess an unusual cyclobutane ring formed by a [2+2]-cycloaddition between two symmetric (for compounds 1-5 and 7-9) or nonsymmetric (for 6) flavonol coumaroyl glucorhamnosides. A plausible biosynthetic pathway for these new compounds based on the frontier molecular orbital theory of cycloaddition reactions is briefly discussed. An antineuroinflammatory screening revealed that biginkgosides E (5) and H (8) inhibited nitric oxide production in lipopolysaccharide-activated BV-2 microglial cells, with IC50 values of 2.91 and 17.23 µM, respectively. Additionally, biginkgoside F (6) showed a significant neuroprotective effect (34.3% increase in cell viability at 1 µM) against Aß25-35-induced cell viability decrease in SH-SY5Y neuroblastoma cells.

Chemical constituents from Melastoma dodecandrum and their inhibitory activity on interleukin-8 production in HT-29 cells.

In search of anti-inflammatory lead compounds from traditional Chinese medicines, a bioassay-guided phytochemical study on Melastoma dodecandrum was carried out. As a result, 18 compounds have been isolated. Their chemical structures were determined on the basis of their physicochemical properties and spectral data. Among the isolates, three pentacyclic triterpenoids, ursolic acid (1), asiatic acid (3) and terminolic acid (6), together with one tannin casuarinin (17), were found to significantly decrease interleukin-8 (IL-8) production in human colon cancer cells. The results imply, at least in part, that the anti-inflammatory effect of M. dodecandrum could be due to inhibition of IL-8 production, demonstrated by these naturally occurring compounds described above.

Lignans from the stems of Clematis armandii ("Chuan-Mu-Tong") and their anti-neuroinflammatory activities.

ETHNOPHARMACOLOGICAL RELEVANCE: The dried stems of Clematis armandii (Caulis clematidis armandii), named "Chuan-Mu-Tong" in Chinese Pharmacopoeia, have been traditionally used as an herbal remedy mainly for inflammation-associated diseases. The Aim of the study is to identify the potential anti-neuroinflammatory components from Clematis armandii. MATERIALS AND METHODS: The ethanol extract of "Chuan-Mu-Tong" was suspended in H2O and exhaustively extracted with CH2Cl2. The CH2Cl2 fraction was successively subjected to column chromatography (CC) over silica gel, Sephadex LH-20, and semi-preparative HPLC. The structures of the isolated compounds were identified by spectroscopic methods and by comparison with those reported in the literature. Their anti-neuroinflammatory activities were evaluated by inhibitory effects on pro-inflammatory mediators [e.g. nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α)] in lipopolysaccharide (LPS)-activated BV-2 cells. RESULTS: One new and sixteen known lignans were isolated and characterized. The absolute configuration of the new lignan, (7R,8S)-9-acetyl-dehydrodiconiferyl alcohol (1), was elucidated by a combination of 1D/2D NMR techniques and the Electronic Circular Dichroism (ECD) spectroscopy based on the empirical helicity rules. The anti-neuroinflammatory bioassay showed that compounds 1, (7R,8S)-dehydrodiconiferyl alcohol (2), erythro-guaiacylglycerol-ß-coniferyl ether (5), and threo-guaiacylglycerol-ß-coniferyl ether (6) displayed significant inhibitory effects on NO production. Among them, neolignans 1 and 2 exhibited more potent activities than the positive control (N(G)-monomethyl-L-arginine, L-NMMA), with an IC50 value of 9.3 and 3.9 µM, respectively. Moreover, both 1 and 2 were also found to concentration-dependently suppress the TNF-α release in LPS-stimulated BV-2 cells. CONCLUSION: The results revealed that lignans are the major components of "Chuan-Mu-Tong", and their anti-neuroinflammatory activities strongly support the traditional application of this herb medicine on inflammation. Moreover, the dihydrobenzo[b]furan neolignans 1 and 2 as well as Caulis clematidis armandii could be further exploited as new therapeutic agents to treat inflammation-mediated neurodegenerative and aging-associated diseases.

Phenolic constituents from the leaves of Cratoxylum formosum ssp. pruniflorum.

One (formosumone A, 1) new and fifteen (2-16) known phenolic compounds were isolated from the leaves of Cratoxylum formosum ssp. pruniflorumm, a substitute for the popular bitter nail tea ("Kuding Tea") generally used in Southeast Asia. Their structures were determined by extensive spectroscopic analysis and by comparison with literature data. Compound 1 possesses a rare scaffold of a flavanone coupled with a phloroglucinol moiety, representing the first example of such a scaffold from the Clusiaceae family. Among the isolates, toxyloxanthone B (11) and vismione D (12) were found to show remarkable anti-neuroinflammatory effects by inhibiting nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine BV-2 microglial cells. Additionally, toxyloxanthone B (11) exhibited significant neuroprotective effect against ß-amyloid(25-35) (Aß(25-35))-induced cell viability decrease in SH-SY5Y neuroblastoma cells.

Leonurusoleanolides E-J, minor spirocyclic triterpenoids from Leonurus japonicus fruits.

Six new (leonurusoleanolides E-J, 1-6) and five known (7-11) nortriterpenoids were isolated and characterized from the dried fruits of Leonurus japonicus. They all contain a distinctive 19(18→17)-abeo-28-noroleanane-type spirocylclic skeleton with a trans or a cis acyl substituent at C-3 or C-23. Similar to the previously known leonurusoleanolides A/B (7/8) and C/D (9/10), compounds 1/2 and 3/4 were also found to exist as equilibrium mixtures of trans and cis isomers. The isolated pure compounds and mixtures were evaluated for their cytotoxicity against a small panel of human cancer cell lines (BGC-823 and KE-97 gastric carcinoma, Huh-7 hepatocarcinoma, Jurkat T cell lymphoblasts, and MCF-7 breast adenocarcinoma) using the CellTiter-Glo luminescent cell viability assay method. Among them, (2α,3ß,17R*,18ß)-3-O-(trans-caffeoyl)-19(18→17)-abeo-28-norolean-12-ene-2,18,23-triol (leonurusoleanolide J, 6) showed the most potent cytotoxic activity, with IC50 values less than 10 µM.

Casuarinines A-J, lycodine-type alkaloids from Lycopodiastrum casuarinoides.

Ten new lycodine-type alkaloids, named casuarinines A-J (1-10), along with eight known analogues (11-18), were isolated from the whole plant of Lycopodiastrum casuarinoides . The new structures were established by spectroscopic methods and chemical transformations. Casuarinines A-D (1-4) and J (10) are common lycodine alkaloids possessing four connected six-membered rings, while tricyclic casuarinines E-H (5-8) are the piperidine ring cleavage products. In particular, casuarinine I (9) has an unprecedented five-membered tetrahydropyrrole ring instead of the piperidine ring. A plausible biosynthetic pathway to 9 is proposed. Among the compounds reported, casuarinine H (8) exhibited significant neuroprotective effect against hydrogen peroxide (H2O2)-induced neuronal cell damage in human neuroblastoma SH-SY5Y cells, while casuarinines C (3) and I (9) showed moderate inhibitory activity against acetylcholinesterase (AChE).

Fomentarols A-D, sterols from the polypore macrofungus Fomes fomentarius.

Four (1-4) hitherto unknown and seven (5-11) known ergostane-type sterols were isolated from the EtOH extract of the dried fruiting bodies of the polypore macrofungus Fomes fomentarius. On the basis of spectroscopic analysis, the structures of polyhydroxylated sterols 1-4 were elucidated to be (22E,24R)-3ß,5α,6ß,14α-tetrahydroxyergosta-7,9(11),22-triene (fomentarol A, 1), (22E,24R)-3ß,5ß,6α,7α-tetrahydroxy-8α,9α-dihydroergosta-14,22-diene (fomentarol B, 2), (22E,24R)-3ß,5α-dihydroxy-6ß-ethoxyergosta-7,22-diene (fomentarol C, 3), and (22E,24S)-3ß,25-dihydroxy-15α-O-ß-D-glucopyranosylergosta-7,22-dien-6-one (fomentarol D, 4), respectively. Rings A/B and B/C are in turn cis-fused in compound 2, which is uncommon in natural ergostane-type sterols. The potential biogenetic relationship of 2 and other ergostane-type sterols isolated from F. fomentarius was briefly discussed. Moderate cytotoxic effects of the isolated sterols against a small panel of human cancer cell lines were also established.

Rearranged abietane diterpenoids from the roots of Clerodendrum trichotomum and their cytotoxicities against human tumor cells.

The roots of the medicinal ornamental plant Clerodendrum trichotomum yielded a series of rearranged abietane diterpenoids, including three 17(15→16)-abeo-abietane (1-3) and three 17(15→16),18(4→3)-diabeo-abietane (4-6) derivatives. Their structures were elucidated by means of spectroscopic methods. The absolute configuration of (10R,16R)-12,16-epoxy-11,14,17-trihydroxy-6-methoxy-17(15→16)-abieta-5,8,11,13-tetraene-7-one (1) was deduced by a combination of single crystal X-ray diffraction analysis and the observed Cotton effects in its circular dichroism (CD) spectrum. All isolates were tested for their cytotoxicities against five human cancer cell lines (BGC-823, Huh-7, KB, KE-97, and Jurkat). Among them, compounds 4, 6, 9, 10, 12, and 14, each possessing a common 17(15→16),18(4→3)-diabeo-abietane framework, were found to have remarkable cytotoxic effects with IC50 values ranging from 0.83 to 50.99 µM.

(24S)-ergostane-3ß,5α,6ß-triol from Hedyotis chrysotricha with inhibitory activity on migration of SK-HEP-1 human hepatocarcinoma cells.

The methanol extract of the whole plant of Hedyotis chrysotricha demonstrated cytotoxicity against SK-HEP-1 human hepatocarcinoma cells in a primary screening for novel antitumour agents. Bioassay-guided fractionation and purification led to an active principle (24S)-ergostane-3ß,5α,6ß-triol (1) along with four inactive compounds (2-5). The in vitro transwell migration assay showed that compound 1 remarkably reduced the migration of SK-HEP-1 cells by 78.9% at a dose of 30 µM, without any apoptotic effect on this cell line. Moreover, all the isolated compounds were further evaluated for their cytotoxicities against another four human cancer cell lines (MCF-7, NUGC3, SH-SY5Y and PC-3).

Eucalyptals D and E, new cytotoxic phloroglucinols from the fruits of Eucalyptus globulus and assignment of absolute configuration.

Two new phloroglucinols, named eucalyptals D (1) and E (2), along with a related known compound (euglobal-In-3, 3) were isolated from the fruits of Eucalyptus globulus. Their structures were established on the basis of extensive spectroscopic studies, revealing that they share a common 3,5-diformyl-isopentyl phloroglucinol unit, but each is instead coupled to a different sesquiterpenoid skeleton (aromadendrene in 1, cadinene in 2, and a spirosesquiterpene in 3). Compound 1 possessed an unusual seven-membered D ring with an ether bridge between C-2 of the aromadendrene moiety and C-2' of the aromatic unit. The absolute configuration of the isolates was defined by the comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Compounds 1-3 exhibited significant in vitro cytotoxicities against a few human cancer cell lines (Huh-7, Jurkat, BGC-823, and KE-97) using the CellTiter-Glo™ luminescent cell viability assay method.

[Effect of mesenchymal stem cells transplantation on heart function after acute myocardial infarction].

OBJECTIVE: To investigate whether mesenchymal stem cells (MSCs) transplantation after acute myocardial infarction (AMI) can improve heart function and decrease infarct size in rabbits and their correlation. METHODS: Twenty-four rabbits were randomly divided into AMI group and MSCs group, each n=12. Exogenous MSCs labeled with bromodeoxyuridine (BrdU) were injected into the border and central area of the ischemic myocardium. Heart function was assessed with echocardiography before transplantation of MSCs and in 6th week after the transplantation. Surviving MSCs in infarcted myocardium were identified by immunohistochemistry. Infarct size was measured histologically. Correlation of heart function and infarct size were analysed. RESULTS: Immunohistochemical stain revealed that BrdU-positive cells were seen in the infarcted myocardium in MSCs group but not in AMI group. Transplantation of MSCs was associated with a significant diminution of left ventricular end-diastolic dimension (LVEDD), and left ventricular end-systolic dimension (LVESD, both P<0.05), and left ventricular ejection fraction (LVEF) and fractional shortening (DeltaFS%)increased (both P<0.05) as compared with AMI group. Infarct size as measured histologically was significant smaller in MSCs group than AMI group (P<0.05). There were negative correlations between LVEF and infarct size in two groups (both P<0.01). CONCLUSION: Exogenous MSCs transplantation can improve heart function by decreasing infarct size and therefore it might be beneficial in the treatment of AMI.

Semisynthesis and antitumor activities of new styryl-lactone derivatives.

Nineteen new derivatives of the naturally occurring compound, goniothalamin, were prepared by chemical modification and semi-synthetic methods. The antitumor activities of these derivatives and goniothalamin were evaluated in vitro against human tumor cell lines, and most of them showed an inhibitory effect against HL-60 cancer cells. The derivatives 10-nitro-goniothalamin and 10-amino-goniothalamin gave selective inhibition concentration (IC50) of 1.10 and 1.14 microg/ml, respectively, against human stomach cancer SGC-7901 cells, while that of etoposide (vp-16) as the positive control was 6.07 microg/ml. Finally, the partition coefficients, logP (pi values), of these derivative molecules, were evaluated by calculating the additive approximate organic fragment logP value.