Chang-Ling Hu

The genus Desmodium (Fabaceae)-traditional uses in Chinese medicine, phytochemistry and pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE Plants of the genus Desmodium (Fabaceae), such as Desmodium styracifolium (Osbeck) Merr. and Desmodium gyrans (L. f.) DC., have a long history of medical use in Traditional Chinese Medicine to treat various ailments including rheumatism, pyrexia, dysentery, wounds, cough, malaria, hepatitis, hemoptysis, etc. In the theory of Traditional Chinese Medicine, most species have the effect of relieving internal heat or fever, neutralizing toxins, inhibiting pain, invigorating blood circulation, suppressing cough and alleviating dyspnea. MATERIALS AND METHODS A bibliographic investigation was accomplished by analyzing secondary sources including Chinese Herbal Classics, and worldwide accepted scientific databases (Pubmed, Scopus and Web of Science, SciFinder) were scrutinized for the available information on the ethnopharmacological uses in Chinese medicine, phytochemistry, pharmacology and toxicology of Desmodium species. RESULTS The genus Desmodium is a large member of the Papilionaceae (Fabaceae) family. It contains about 350 plant species used for both feeding stuffs and herbal medicines, of which only about 30 species have been phytochemically or pharmacologically investigated. Desmodium plant extracts, as well as the active principles, have been experimentally studied for their anti-inflammatory, cytotoxic, antidiabetic, antinephrolithic, antibacterial, and nootropic activities in vitro or in vivo. And so far, a total of 212 compounds have been isolated from 15 Desmodium species and characterized mainly as flavonoids and alkaloids, followed by terpenoids, steroids, phenols, phenylpropanoids, glycosides and a number of volatile oils. The remaining unrevealed species are recorded chiefly in Asia and Africa being used in empirical treatment for various diseases. CONCLUSIONS Desmodium species have long been used in TCM to treat various ailments. Available scientific references revealed that the traditional medical uses of some important Desmodium species in TCM have been evaluated by modern pharmacological studies. As literature demonstrated, flavonoids and alkaloids are perhaps responsible for most of the activities shown by the plants of this genus. Further studies are still required to reveal the structure-activity relationship of these active constituents.

Cytotoxic phenylpropanoid glycosides from Fagopyrum tataricum (L.) Gaertn.

Fagopyrum tataricum (L.) Gaertn (tartary buckwheat) is an ancient dicotyledonous crop belonging to Polygonaceae family. Besides its benefits for human consumption, tartary buckwheat is also an important folk medicine in China for its antioxidant, antitumour, hypotensive, hypoglycaemic and hypolipidaemic activities. Phytochemical investigation of the ethyl acetate fraction of tartary buckwheat roots led to the isolation of seven new phenylpropanoid glycosides, tatarisides A-G (1-7), together with a known phenylpropanoid glycoside, diboside A (8). Their structures were elucidated by means of spectroscopic methods. All compounds (1-8) were evaluated for their cytotoxic activity against four human cancer cell lines (A-549, HCT116, ZR-75-30 and HL-60). Tatariside C (3) was the most active compound with IC50 values of 6.44-7.49μg/ml against the four tested cell lines.

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 Aβ25-35-induced cell viability decrease in SH-SY5Y neuroblastoma cells.

Antiosteoporotic activity and constituents of Podocarpium podocarpum

Our study aimed to investigate the antiosteoporotic properties of the ethanol extract of Podocarpium podocarpum (DC.) Yang et Huang (PE) in ovariectomized (OVX) rats and to characterize the active constituents. As a result, PE significantly inhibited the increased urinary Ca excretion and activity of bone resorption markers including tartrate-resistant acid phosphatase (TRAP), deoxypyridinoline crosslinks and cathepsin K in OVX rats, whereas exhibited little effects on the body, uterus and vagina weight. Detailed micro-CT analysis showed that PE notably enhanced bone quality, with increased bone mineral content (BMC), bone volume fraction (BVF), connectivity density (CD), tissue mineral content (TMC), tissue mineral density (TMD) and trabecular number (Tb. N), and decreased trabecular separation (Tb. Sp), in OVX animal. Those findings implied that PE had notable antiosteoporotic effect, especially effective in preventing bone resorption, with little side-effects on reproductive tissue. Further chemical investigation led to the isolation of 17 flavonoids, most of which showed significantly stimulatory effect on osteoblastic proliferation, ALP activity and mineralized nodes formation as well as inhibitory effect on osteoclastic TRAP activity in osteoblastic and osteoclastic cells. Our results indicated that PE, with abundant flavonoids, had remarkable antiosteoporotic activity and therefore can be a promising candidate for the treatment of postmenopausal osteoporosis induced by estrogen deficiency through herbal remedy.

Antitumor activity of tatariside F isolated from roots of Fagopyrum tataricum (L.) Gaertn against H22 hepatocellular carcinoma via up-regulation of p53.

BACKGROUND Fagopyrum tataricum (L.) Gaertn is a famous drinking food and herbal medicine in China, and have been commonly used for treating various diseases. PURPOSE This study was designed to investigate the antitumor effect of tatariside F (TF) isolated from the roots of F. tataricum against H22 hepatocellular carcinoma (HCC) in vitro and in vivo and explore the possible mechanisms. METHODS In our present study, the anti-proliferative effect of TF against H22 cells was evaluated by MTT method. Furthermore, a mice xenograft model was established to investigate the antitumor effect of TF on HCC in vivo, and the possible mechanisms were determined by western blot and fluorescence polarization binding assay. In addition, the protective effect of TF on liver was also investigated by examining the histopathological changes and determining the liver biochemical parameters. RESULTS Our results demonstrated that TF possessed notable antitumor effect against HCC both in vivo and in vitro, and the possible mechanism might be related to up-regulation of the protein expressions of Bax and p53, and down-regulation of Bcl-2. Whats more, TF also exhibited protective effects against CTX (cyclophosphamide)-induced liver damages when co-administrated with CTX. CONCLUSION Our study suggested that TF possess notable antitumor effects against HCC and might play a favorable role in drug combination therapy against tumors with protective effect on liver.

Phenylpropanoids from Podocarpium podocarpum

Abstract Context: Podocarpium podocarpum (DC.) Yang et Huang (Leguminoseae) is a very important Podocarpium species with significant anti-inflammatory, analgesic and anti-pyretic activities, which has not yet been subjected to adequate phytochemical investigation. Objective: To isolate and identify bioactive compounds from P. podocarpum. Materials and methods: Ethanol extract of the whole plant of P. podocarpum was subjected to repeated column chromatography. Chemical structures of the compounds were identified by 1D, 2D-NMR spectra and MS data. Human cervical carcinoma (HeLa) and pancreatic carcinoma (PANC-1) cell lines were employed to evaluate the in vitro cytotoxic activity of the isolated constituents at six concentrations (0.001, 0.01, 0.1, 1.0, 10.0, 100.0 μg/ml). Results: A new phenylpropanoid glycoside, podocarioside A (1), together with four known compounds, (E)-3-(4-hydroxy-3-propoxyphenyl) acrylic acid (2), schizandrin (3), dehydrodiconiferyl alcohol (4) and dihydrodehydrodiconiferyl alcohol (5), were isolated from P. podocarpum. Compounds 1, 3 and 4 showed moderate cytotoxic against HeLa cells with IC50 values of 38.62, 8.64 and 5.85 μg/mL, respectively, while none exhibited toxicity against PANC-1 cells. Discussion and conclusion: This is the first report on the isolation and identification of bioactive compounds from P. podocarpum. In vitro cytotoxic assay of the isolated constituents establishes the potential of those components as antitumor agents.

Anti-neuroinflammatory diterpenoids from the endangered conifer Podocarpus imbricatus

Abstract Ten diterpenoids including three new abietanes (1–3) were isolated from the twigs and needles of Podocarpus imbricatus, an endangered conifer growing in a Cantonese garden. The new structures were established by means of spectroscopic methods. Among the isolates, 3β-hydroxy-abieta-8,11,13-trien-7-one (5), decandrin G (6), and 7,15-pimaradien-18-oic acid (8) showed significant anti-neuroinflammatory activities by inhibiting the overproduction of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated murine BV-2 microglial cells, with IC50 values of 3.7, 11.1, and 4.5 μM, respectively.

Lignans and phenylpropanoids from Fagopyrum tataricum roots

0009-3130/12/4802-0303 2012 Springer Science+Business Media, Inc. 1) Department of Pharmacognosy, School of Pharmacy, Second Military Medical University, Shanghai 200433, P. R. China, fax: +86 21 81871300; +86 21 81871309, e-mail: qinsmmu@126.com; zheng_chengjian@hotmail.com; 2) Department of Pharmacy, Fujian University of Traditional Chinese Medicine, Fuzhou, 350108, P. R. China; 3) Department of Pharmaceutical Analysis, School of Pharmacy, NingXia Medical Univercity, 1160 Shenli Street, Yinchuan 750004, P. R. China. Published in Khimiya Prirodnykh Soedinenii, No. 2, March–April, 2012, pp. 271–272. Original article submitted December 25, 2010. Chemistry of Natural Compounds, Vol. 48, No. 2, May, 2012 [Russian original No. 2, March–April, 2012]