Sumiko Hyuga

Ephedrine alkaloids-free Ephedra Herb extract: a safer alternative to ephedra with comparable analgesic, anticancer, and anti-influenza activities

It is generally accepted that the primary pharmacological activities and adverse effects of Ephedra Herb are caused by ephedrine alkaloids. Interestingly, our research shows that Ephedra Herb also has ephedrine alkaloid-independent pharmacological actions, such as c-MET inhibitory activity. This study describes the preparation of an ephedrine alkaloids-free Ephedra Herb extract (EFE) by ion-exchange column chromatography, as well as in vitro and in vivo evaluation of its pharmacological actions and toxicity. We confirmed that EFE suppressed hepatocyte growth factor (HGF)-induced cancer cell motility by preventing both HGF-induced phosphorylation of c-Met and its tyrosine kinase activity. We also investigated the analgesic effect of EFE. Although the analgesic effect of Ephedra Herb has traditionally been attributed to pseudoephedrine, oral administration of EFE reduced formalin-induced pain in a dose-dependent manner in mice. Furthermore, we confirmed the anti-influenza virus activity of EFE by showing inhibition of MDCK cell infection in a concentration-dependent manner. All assessments of toxicity, even after repeated oral administration, suggest that EFE would be a safer alternative to Ephedra Herb. The findings described here suggest that EFE has c-Met inhibitory action, analgesic effect, and anti-influenza activity, and that it is safer than Ephedra Herb extract itself. Therefore, EFE could be a useful pharmacological agent.

Herbacetin, A Constituent of Ephedrae herba, Suppresses the HGF-Induced Motility of Human Breast Cancer MDA-MB-231 Cells by Inhibiting c-Met and Akt Phosphorylation

Ephedrae herba suppresses hepatocyte growth factor-induced cancer cell motility by inhibiting tyrosine phosphorylation of the hepatocyte growth factor receptor, c-Met, and the PI3K/Akt pathway. Moreover, Ephedrae herba directly inhibits the tyrosine-kinase activity of c-Met. Ephedrine-type alkaloids, which are the active component of Ephedrae herba, do not affect hepatocyte growth factor-c-Met-Akt signalling, prompting us to study other active molecules in the herb. We recently discovered herbacetin glycosides and found that their aglycon, herbacetin, inhibits hepatocyte growth factor-c-Met-Akt signalling. This study revealed a novel biological activity of herbacetin. Herbacetin suppressed hepatocyte growth factor-induced motility in human breast cancer MDA-MB-231 cells by inhibiting c-Met and Akt phosphorylation and directly inhibiting c-Met tyrosine kinase activity. The effects of herbacetin were compared to those of kaempferol, apigenin, and isoscutellarein, all of which have similar structures. Herbacetin inhibition of hepatocyte growth factor-induced motility was the strongest of those for the tested flavonols, and only herbacetin inhibited the hepatocyte growth factor-induced phosphorylation of c-Met. These data suggest that herbacetin is a novel Met inhibitor with a potential utility in cancer therapeutics.

Ganglioside GD1a negatively regulates hepatocyte growth factor expression through caveolin-1 at the transcriptional level in murine osteosarcoma cells

BACKGROUND Hepatocyte growth factor (HGF) is a mesenchyme-derived, multifunctional protein that is implicated in tumor growth and invasive behavior. Some tumor cells express both HGF and its receptor MET, forming an autocrine loop that permanently activates it. Ganglioside GD1a suppresses metastatic capacity in murine FBJ osteosarcoma cells and MET phosphorylation activated by HGF binding, but the signaling pathway controlling HGF production has not been fully explored. METHODS Expression of HGF, caveolins, or MET of the cells that had been transfected with siRNA or cDNA directed to GM2/GD2 synthase, caveolin-1 or HGF was determined by semi-quantitative RT-PCR and Western blots. RESULTS HGF expression in highly metastatic, GD1a-deficient FBJ-LL cells was higher than that in the poorly metastatic, GD1a-rich FBJ-S1 cells. Transfection with GM2/GD2 synthase cDNA increased GD1a levels in FBJ-LL cells and suppressed HGF expression. Treatment with siRNAs directed toward GM2/GD2 synthase in FBJ-S1 cells reduced gangliosides and augmented HGF expression. GD1a was found to be the only ganglioside species suppressing HGF expression upon addition to FBJ-LL cells. HGF expression was decreased by GD1a addition to FBJ-LL cells after 48h, enough to induce caveolin-1 expression. Silencing caveolin-1 up-regulated HGF, and the re-introduction of caveolin-1 cDNA decreased HGF expression. Caveolin-1 suppressed MET phosphorylation. We also found GD1a regulation of HGF in Lewis lung carcinoma cells. CONCLUSIONS HGF expression was negatively regulated by GD1a through caveolin-1 at the transcriptional level via the suppression of MET phosphorylation. GENERAL SIGNIFICANCE This is the first report that ganglioside GD1a negatively regulates HGF expression through caveolin-1.

Two flavone C -glycosides as quality control markers for the manufacturing process of ephedrine alkaloids-free Ephedra Herb extract (EFE) as a crude drug preparation

As part of our continuing study of ephedrine alkaloids-free Ephedra Herb extract (EFE) in pursuit of its approval as a crude drug preparation, we identified two quantitative markers for the quality control of the manufacturing process of EFE and sought to establish cost-effective and simple methods for quantitative analyses. We analysed Ephedra Herb extracts grown in different habitats and collection years by liquid chromatography/high-resolution mass spectrometry (LC/HRMS) and detected two notable peaks common to each extract. These peaks were identified as vicenin-2 (1) and isovitexin 2″-O-rhamnoside (2). Quantitative analyses using the isocratic condition of LC/MS showed that the content percentages of 1 and 2 in EFE were 0.140–0.146% and 0.350–0.411%, respectively. We concluded that 1 and 2 were adequate quality control markers for quantitative analysis of EFE. Furthermore, we quantitatively analysed apigenin (3), an aglycon common to 1 and 2, and found that the conversion factors of 1 to 3 and 2 to 3 were 1.3 and 1.5, respectively. Therefore, we concluded that 3 was a secondary standard for quantifying the contents of 1 and 2 in EFE. A series of results obtained from this study will be valuable for the quality control of EFE.

Ephedrine Alkaloids-Free Ephedra Herb Extract, EFE, Has No Adverse Effects Such as Excitation, Insomnia, and Arrhythmias

Ephedrine alkaloids-free Ephedra Herb extract (EFE) has been developed to eliminate the adverse effects caused by ephedrine alkaloid-induced sympathetic hyperactivation. Previously, we reported that EFE possesses analgesic, anti-influenza, and cancer metastatic inhibitory effects at comparable levels to that of Ephedra Herb extract (EHE). However, it has not yet been demonstrated that EFE is free from the known side effects of EHE, such as excitation, insomnia, and arrhythmias. In this study, the incidence of these adverse effects was compared between mice administered EHE and those administered EFE. Increased locomotor activity in an open-field test, reduced immobility times in a forced swim test, and reduced sleep times in a pentobarbital-induced sleep test were observed in EHE-treated mice, when compared to the corresponding values in vehicle-treated mice. In contrast, EFE had no obvious effects in these tests. In electrocardiograms, atrial fibrillation (i.e., irregular heart rhythm, absence of P waves, and appearance of f waves) was observed in the EHE-treated mice. It was suggested that this atrial fibrillation was induced by stimulation of adrenaline β1 receptors, but not by hypokalemia. However, EFE did not affect cardiac electrophysiology. These results suggest that the abovementioned side effects are caused by ephedrine alkaloids in EHE, and that EFE is free from these adverse effects, such as excitation, insomnia, and arrhythmias. Thus, EFE is a promising new botanical drug with few adverse effects.

Correction to: Ephedra Herb extract activates/desensitizes transient receptor potential vanilloid 1 and reduces capsaicin-induced pain

The article Ephedra Herb extract activates/desensitizes transient receptor potential vanilloid 1 and reduces capsaicin-induced pain, written by Shunsuke Nakamori, Jun Takahashi, Sumiko Hyuga, Toshiko Tanaka-Kagawa, Hideto Jinno, Masashi Hyuga, Takashi Hakamatsuka, Hiroshi Odaguchi, Yukihiro Goda, Toshihiko Hanawa and Yoshinori Kobayashi, was originally published Online First without open access. After publication in volume 71, issue 1, page 105–113 the author decided to opt for Open Choice and to make the article an open access publication. Therefore, the copyright of the article has been changed to

A Double-Blind, Randomized, Crossover Comparative Study for Evaluating the Clinical Safety of Ephedrine Alkaloids-Free Ephedra Herb Extract (EFE)

Ephedra Herb is an important crude drug; it is used in various Traditional Japanese Medicine (Kampo) formulations. Its significant pharmacological effects have been believed to be attributed to ephedrine and pseudoephedrine, which sometimes induce adverse effects. On the other hand, it has been reported that some of these pharmacological effects are not dependent on ephedrine or pseudoephedrine. Ephedrine alkaloids-free Ephedra Herb extract has been newly developed. It has been reported to have analgesic, anti-influenza, and antimetastatic effects. This clinical trial was aimed at verifying the noninferiority of EFEs safety compared to that of Ephedra Herb extract (EHE) in humans. This was a single-institution, double-blinded, randomized, two-drug, two-stage, crossover comparative study. Twelve healthy male subjects were equally and randomly allocated into two groups: prior administration of EFE (EFE-P) and prior administration of EHE (EHE-P). In Stage 1, EFE and EHE were orally administered to the EFE-P and EHE-P groups, respectively, for six days. After a 4-week washout period, Stage 2 was initiated wherein the subjects were given a study drug different from Stage 1 study drug for six days. Eleven adverse events with a causal relationship to the study drugs (EHE: 8; EFE: 3) were noted; all events were mild in severity. With regard to the incidence of adverse events, EHE and EFE administration, respectively, accounted for 4 cases (out of 12 subjects, similarly below) and 1 case of increased pulse rate (p=0.32) and 3 cases and 1 case of insomnia (p=0.59). Further, there was one case of hot flashes (p=1.00) due to EFE administration and one case of dysuria (p=1.00) due to EHE administration. There were no significant differences in the incidences of adverse events between EHE administration and EFE administration. Therefore, we concluded that EFE is not inferior to EHE in terms of safety.

Ephedrae herba stimulates hepatocyte growth factor-induced MET endocytosis and downregulation via early/late endocytic pathways in gefitinib-resistant human lung cancer cells.

The MET tyrosine kinase receptor and its ligand, hepatocyte growth factor (HGF), are known to be overexpressed in a variety of malignant tumor cells, and are implicated in the development of gefitinib-resistance in human non-small cell lung cancer (NSCLC) cells. Ephedrae herba was previously reported to prevent HGF-induced cancer cell motility by directly suppressing HGF/MET signaling through the inhibition of MET tyrosine kinase, and treatment with its extract also considerably reduced MET protein levels. To further investigate the mechanism underlying the Ephedrae herba-induced inhibition of MET phosphorylation as well as its degradation and subsequent disappearance, we examined the effect of Ephedrae herba on HGF-stimulated MET endocytosis and downregulation via early/late endocytic pathways in an NSCLC cell line. Using immunofluorescence microscopy, we found that pretreatment of cells with Ephedrae herba extract dramatically changed the intracellular distribution of plasma membrane-associated MET, and that the resultant MET staining was distributed throughout the cytoplasm. Pretreatment of the cells with Ephedrae herba extract also led to the rapid loss of MET and phosphorylated (p)-MET in HGF-stimulated cells. In contrast, inefficient endocytic delivery of MET and p-MET from early to late endosomes was observed in the absence of Ephedrae herba extract, since considerable amounts of the internalized MET accumulated in the early endosomes and were not delivered to lysosomes up to 1 h after HGF-stimulation. Furthermore, large amounts of MET and p-MET that had accumulated in late endosomes of Ephedrae herba-pretreated cells after HGF stimulation were observed along with bafilomycin A1. Therefore, we inferred that degradation of MET occurred in the late endosome/lysosome pathway. Moreover, western blot analysis revealed the accelerated degradation of MET and p-MET proceeds in cells pretreated with Ephedrae herba extract. Collectively, our results suggest that some components of Ephedrae herba have a novel role in promoting HGF-stimulated MET and p-MET endocytosis followed by its downregulation, likely mediated by the early/late endocytic pathways.