Iridoids of garrya elliptica as plant growth inhibitors

Extracts from catkins of Garrya elliptica inhibit the growth of wheat embryos. The components responsible for this activity have been identified as the iridoids geniposide and geniposidic acid together with their aglucones.     

Iridoids as DNA topoisomerase I poisons

The discovery of new topoisomerase I inhibitors is necessary since most of the antitumor drugs are targeted against type II and only a very few can specifically affect type I. Topoisomerase poisons generate toxic DNA damage by stabilization of the covalent DNA-topoisomerase cleavage complex and some have therapeutic efficacy in human cancer. Two iridoids, aucubin and geniposide, have shown antitumoral activities, but their activity against topoisomerase enzymes has not been tested. Here it was found that both compounds are able to stabilize covalent attachments of the topoisomerase I subunits to DNA at sites of DNA strand breaks, generating cleavage complexes intermediates so being active as poisons of topoisomerase I, but not topoisomerase II. This result points to DNA damage induced by topoisomerase I poisoning as one of the possible mechanisms by which these two iridoids have shown antitumoral activity, increasing interest in their possible use in cancer chemoprevention and therapy.     

高效液相色谱法测定山栀子中栀子甙的含量

采用高效液相色谱法测定中药山栀子（Cardenia jasminoides Ellis）中保肝利胆的主要成分栀子甙（geniposide）的含量。分析结果表明,本方法重现性好,平均加样回收率为100．90％,RSD为2．00％。用此方法测定未知样品山栀子中栀子甙的平均含量为3．463g/100g。     

Penta-acetyl geniposide-induced C6 glioma cell apoptosis was associated with the activation of protein kinase C-delta

Herbal medicine has been utilized to treat a variety of diseases, including cancer. On the other hand, disturbance of apoptosis is often observed in cancer cells. It has been reported that protein kinase C (PKC) isoforms are involved in the signaling of apoptosis. In the present study, we investigate the antitumor effect and possible mechanism of a herbal-originated product, (Ac)(5)GP. We demonstrate that (Ac)(5)GP treatment results in DNA fragmentation of C6 glioma cells dose-dependently. Stimulated by (Ac)(5)GP, PKCdelta and PKCzeta were activated and translocated to the cell membrane fraction. Flow cytometry analysis showed that PKCdelta, but not PKCzeta inhibition blocks the (Ac)(5)GP-induced apoptosis by decreasing the cell population of sub G1 peak. However, the mRNA levels of PKCdelta and PKCzeta were not altered by (Ac)(5)GP-induced glioma cell apoptosis. These results suggested that the treatment of (Ac)(5)GP induces apoptosis of tumor cells through the activation but not the synthesis of PKCdelta.     

Toxicity Evaluation of Geniposide on MCF-7 Cancer Cells

As one of the adjuvant treatments for cancer treatment, traditional Chinese medicine treatment has a wide range of cancer treatments, such as preventing metastasis and relapse, improving the efficacy of radiotherapy and chemotherapy, reducing the side effects of chemotherapy, improving body function, extending life and improving the life quality. Geniposide (GEN) is a bioactive substance extracted from the fruit of gardenia. In recent years, it has attracted attention due to its anti-tumor effect. In this study, we aimed to investigate whether GEN could inhibit the proliferation of human breast cancer cells (MCF-7) and promote its apoptosis. The half-inhibitory concentration (IC50) values of GEN were firstly determined as 16.06, 14.85 and 13.14 mg/mL by the CCK-8 experiment after cells treated for 24 h, 48 h, and 72 h, respectively. The inhibitory effect of GEN on MCF-7 cells was in concentration- and time-dependent manners from the results of CCK-8 experiment and Live/Dead staining. AO/EB staining result has shown that GEN has induced MCF-7 cell apoptosis.     

栀子黄色素的醇提制备及其稳定性研究

通过单因素实验,考察栀子黄色素乙醇提取工艺。乙醇提取最优工艺条件为：乙醇浓度30％、液固比8：1、提取温度60℃、提取次数2次、每次1h。在此条件下,栀子黄色素、栀子苷和总三萜酸的提取率分别为1．32、110．76和94．91mg／g。     

Geniposide alleviates non‐alcohol fatty liver disease via regulating Nrf2/AMPK/mTOR signalling pathways

Non‐alcohol fatty liver disease (NAFLD) is a common disease which causes serious liver damage. Geniposide (GEN), a kind of iridoid glycoside extracted from Gardenia jasminoides fruit, has many biological effects, such as resistance to cell damage and anti‐neurodegenerative disorder. Lipid accumulation was obvious in tyloxapol‐induced liver and oil acid (OA) with palmitic acid (PA)‐induced HepG2 cells compared with the control groups while GEN improved the increasing conditions. GEN significantly lessened the total cholesterol (TC), the triglyceride (TG), low‐density lipoprotein (LDL), very low‐density lipoprotein (VLDL), myeloperoxidase (MPO), reactive oxygen species (ROS) and increased high‐density lipoprotein (HDL), superoxide dismutase (SOD) to response the oxidative stress via activating nuclear factor erythroid‐2–related factor 2 (Nrf2), haeme oxygenase (HO)‐1 and peroxisome proliferator‐activated receptor (PPAR)α which may influence the phosphorylation of adenosine 5’‐monophosphate–activated protein kinase (AMPK) signalling pathway in mice and cells. Additionally, GEN evidently decreased the contents of sterol regulatory element‐binding proteins (SREBP)‐1c, phosphorylation (P)‐mechanistic target of rapamycin complex (mTORC), P‐S6K, P‐S6 and high mobility group protein (HMGB) 1 via inhibiting the expression of phosphoinositide 3‐kinase (PI3K), and these were totally abrogated in Nrf2^?/? mice. Our study firstly proved the protective effect of GEN on lipid accumulation via enhancing the ability of antioxidative stress and anti‐inflammation which were mostly depend on up‐regulating the protein expression of Nrf2/HO‐1 and AMPK signalling pathways, thereby suppressed the phosphorylation of mTORC and its related protein.     

Preparative isolation and purification of geniposide from gardenia fruits by centrifugal partition chromatography

The iridoid glycoside, geniposide was purified by centrifugal partition chromatography (CPC) with a two-phase solvent system composed of ethyl acetate:isopropanol:water (3:2:5, v/v) from an 80% methanolic extract of fruits of Gardenia jasminoides. Preparative CPC yielded 56.2 mg of geniposide in a one-step separation of 500 mg of extract, with a purity of 95% as determined by HPLC. Isolated geniposide was identified from its 1H-NMR, 13C-NMR and MS spectra.