Mechanism of proliferation arrest of embryonic cells of Xenopus by diterpene compounds

The Role of Ingenane Diterpenes in Cancer Therapy: From Bioactive Secondary Compounds to Small Molecules

Diterpenes are a class of critical taxonomic markers of the Euphorbiaceae family, representing small compounds (eg, molecules) with a wide range of biological activities and multi-target therapeutic potential. Diterpenes can exert different activities, including antitumor and multi-drug resistance-reversing activities, and antiviral, immunomodulatory, and anti-inflammatory effects, mainly due to their great structural diversity. In particular, one polycyclic skeleton has been highlighted: ingenane. Besides this natural diterpene, promising polycyclic skeletons may be submitted to chemical modification—by in silico approaches, chemical reactions, or biotransformation—putatively providing more active analogs (eg, ingenol derivatives), which are currently under pre-clinical investigation. This review outlines the current mechanisms of action and potential therapeutic implications of ingenol diterpenes as small cancer molecules.

Effect of the vinegar-process on chemical compositions and biological activities of Euphorbia kansui: A review

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional Chinese medicine (TCM) the root of Euphorbia kansui S.L.Liou ex S.B.Ho (EK), is used for treating edema and ascites but is also of toxicological concerns. And the clinical applications of EK have been seriously restricted for its severe toxicity. To reduce its toxicity, a commonly used clinical practice is processing it with vinegar.

AIM OF THE REVIEW

This review aimed to summarize and discuss updated information on biological activities and phytochemistry of EK before and after vinegar-processing, and provide feasible insights for further research on the chemical composition, toxicity and pharmacological effects of EK before and after vinegar-processing.

MATERIALS AND METHODS

The relevant information on chemical compositions and biological activities of EK before and after vinegar-processing was collected from scientific databases (Google Scholar, PubMed, CNKI, SpringerLink, Web of Science, Wiley Online Library and SciFinder). Additionally, published and unpublished Ph.D. and MSc. dissertations were also obtained from online databases.

RESULTS AND DISCUSSIONS

Diuretic and purgative effect of EK are well documented pharmacologically as are acute, irritant and organic toxic effects. Some of about terpenoids reported have antiproliferative effects on cancer cells and potential antiviral effect. After processing with vinegar, the contents of terpenoids mostly were reduced (ingenane and jatrophane type) with some new compounds being generated (unclear). Also, the toxicity of EK was decreased (using mice, rats and zebrafish embryos model), while the diuretic and purgative effects were retained (using cancerous ascites model rats and mice).

CONCLUSIONS

While some evidence exists for the reduction of toxicity without compromising the pharmacological effects of EK after vinegar processing, the specific mechanism of action remains unknown. Consequently, further research is necessary to investigate the mechanisms and the relationship between vinegar processing and changes in the chemical composition as well as pharmacological effects/toxicity. This is essential before a safe clinical use can be endorsed.

Therapeutic Potential of Essential Oils Focusing on Diterpenes

Among all plant derivates, essential oils (EOs) have gained the attention of many scientists. Diterpenes, a family of components present in some EO, are becoming a milestone in the EOs world. The goal of this review is to describe a scenario of diterpenes taking into health-consumption deportment. Previous studies revealed that diterpenes have antioxidant, antimicrobial, antiviral, antiprotozoal, cytotoxic, anticancer, antigenotoxic, antimutagenic, chemopreventive, antiinflammatory, antinociceptive, immunostimulatory, organoprotective, antidiabetic, lipid-lowering, antiallergic, antiplatelet, antithrombotic, and antitoxin activities. In conclusion, diterpenes may be an immense featuring concern in pharmaceutical consumption from a drug discovery point of view. Copyright © 2016 John Wiley & Sons, Ltd.

The Chemical and Biological Properties of Euphorbia kansui

Kansui, the root of Euphorbia kansui T.N. Liou ex T.P. Wang, is a well-known traditional Chinese medicine. This paper reviews advances in investigations of the botany, the phytochemistry, the analytical method, the pharmacology and the toxicology of kansui. Nearly 100 compounds have been isolated from kansui and identified, and diterpenes and triterpenes are considered to be the characteristic and bio-active constituents of kansui. They possess multiple pharmacological activities, including diuretic, purgation, and antitumor effects. However, they also have a degree of toxicity, and can cause skin, oral, and gastrointestinal irritation. In this paper, the toxicity-efficacy relationship, attenuation and incompatibility of kansui are further discussed. Several future investigations of kansui are also proposed, all of which would improve the identification of kansui and other toxic herbs, as well as further their utilization.

Anticancer drugs from traditional toxic Chinese medicines

Many anticancer drugs are obtained from natural sources. Nature produces a variety of toxic compounds, which are often used as anticancer drugs. Up to now, there are at least 120 species of poisonous botanicals, animals and minerals, of which more than half have been found to possess significant anticancer properties. In spite of their clinical toxicity, they exhibit pharmacological effects and have been used as important traditional Chinese medicines for the different stages of cancer. The article reviews many structures such as alkaloids of Camptotheca acuminata, Catharanthus roseus and Cephalotaxus fortunei, lignans of Dysosma versipellis and Podophyllum emodi, ketones of Garcinia hanburyi, terpenoids of Mylabris and Ginkgo biloba, diterpenoids of Tripterygium wilfordii, Euphorbia fischeriana, Euphorbia lathyris, Euphorbia kansui, Daphne genkwa, Pseudolarix kaempferi and Brucea javanica, triterpenoids of Melia toosendan, steroids of Periploca sepium, Paris polyphylla and Venenum Bufonis, and arsenic compounds including Arsenicum and Realgar. By comparing their related phytochemistry, toxic effects and the recent advances in understanding the mechanisms of action, this review puts forward some ideals and examples about how to increase antitumour activity and/or reduce the side effects experienced with Chinese medicine.

Inhibition of cellular proliferation by diterpenes, topoisomerase II inhibitor

We examined the effects of 12 terpene compounds derived from the roots of Euphorbia kansui on the proliferative activity of Xenopus embryo cells. Eight of these compounds showed significant inhibition of cellular proliferation even at low concentrations, while four of them needed to be present at higher concentrations to inhibit cellular proliferation. In order to define the mechanism of inhibition of cellular proliferation by these compounds, the effects of diterpene compounds on the activity of topoisomerase II were measured. Most of the diterpene compounds that inhibited cellular proliferation also inhibited topoisomerase II activity.

Diterpenoids

This review covers the isolation and structures of diterpenoids, including labdanes, clerodanes,pimaranes, abietanes, kauranes, cembranolides, taxanes and marine diterpenoids. The literature from January to December 2005 is reviewed, and 195 references are cited.

3-O-(2,3-Dimethylbutanoyl)-13-O-decanoylingenol from Euphorbia kansui Suppresses IgE-Mediated Mast Cell Activation

Aggregation of the high affinity receptor for IgE (FcepsilonRI) on mast cells by antigen and IgE complex induces release of chemical mediators, leading to acute allergic inflammation. We recently found that 3-O-(2,3-dimethylbutanoyl)-13-O-decanoylingenol (DBDI), purified from the Euphorbia kansui L., inhibits degranulation in rat basophilic leukemia 2H3 cells upon aggregation of the FcepsilonRI. In the present study, we demonstrated that the DBDI significantly inhibits release of beta-hexosaminidase, synthesis of eicosanoids, and mobilization of intracellular Ca(2+) in the bone marrow-derived mouse mast cells stimulated with IgE and antigen. Furthermore, we revealed that phosphorylation of Syk, phospholipase C-gamma(2), and extracellular signal-related kinase 1/2 is significantly suppressed in the DBDI-treated mast cells. These findings suggest that the DBDI may have a therapeutic potential for allergic diseases by inhibiting intracellular signaling pathways for activation and chemical mediator release in mast cells.