Hexane/Ethanol Extract of Glycyrrhiza uralensis Licorice Suppresses Doxorubicin-Induced Apoptosis in H9c2 Rat Cardiac Myoblasts

Department of Food Science and Nutrition, Hallym University, Chuncheon 200-702, South Korea.
Experimental Biology and Medicine (Impact Factor: 2.17). 11/2008; 233(12):1554-60. DOI: 10.3181/0807-RM-221
Source: PubMed

ABSTRACT Doxorubicin (DOX) is an anthracycline antibiotic, and has been recognized as one of the most effective anti-neoplastic agents in cancer chemotherapy. However, its usefulness is limited by its profound cardiotoxicity. Licorice is one of the most frequently prescribed agents in traditional herbal medicine, and is also employed as a natural sweetening additive. In traditional Chinese medicine, licorice root is added to a variety of herbal preparations to detoxify the effects of the other herbs in the preparation. In the present study, we explored the possibility that Glycyrrhiza uralensis licorice may alleviate DOX-induced cardiotoxicity. The hexane/ethanol extract of Glycyrrhiza uralensis (HEGU), which lacks glycyrrhizin, was prepared because glycyrrhizin intake has previously been reported to induce hypertension. In an effort to determine whether HEGU ameliorates DOX-induced cytotoxicity in H9c2 rat cardiac myoblasts, the cells were pretreated with 0-15 mg/L HEGU, then treated with doxorubicin. The pretreatment of cells with HEGU resulted in a significant mitigation of DOX-induced reductions in cell numbers (34 +/- 7%) and increases in apoptosis (53 +/- 1%). The Western blot analysis of cell lysates showed that HEGU suppressed DOX-induced increases in the levels of p53, phospho-p53 (Ser 15), and Bax. In addition, HEGU induced an increase in the levels of Bcl-xL, regardless of DOX-treatment. HEGU inhibited the DOX-induced cleavage of caspases 9, 3, and 7, as well as DOX-induced poly(ADP-ribose) polymerase cleavage. Furthermore, HEGU caused reductions in the viable cell numbers of HT-29 human colon cancer cells (IC50 = 10.7 +/- 0.3 mg/L), MDA-MB-231 human breast cancer cells (IC50 = 7.5 +/- 0.1 mg/L), and DU145 human prostate cancer cells (IC50 = 4.7 +/- 0.5 mg/L). HEGU augmented DOX-induced reductions in the viability of DU145 cells (15 +/- 1%). These results indicate that HEGU may potentially be an effective agent for the alleviation of DOX-induced cardiotoxicity.

Download full-text


Available from: Jong-Sang Kim, Apr 15, 2014
1 Follower
39 Reads
  • Source
    • "[21,22] In order to modify the composition of the extracts and to exclude toxic fractions, roasting as well as the use of different solvents has been employed. [13,23] The ethanol extracts of roasted licorice have been reported to exert potent anti-inflammatory properties, [24] neuro-protective effects against ischemic damage, [13] and protective effects against mesangial fibrosis and glomerulosclerosis in diabetes nephropathy. [25] The present results clearly demonstrated that EERL is more potent and efficacious than EEUL in inhibiting the growth of prostate and colon cancer cells (Fig. 1). "
    [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND/OBJECTIVE Licorice has been shown to possess cancer chemopreventive effects. However, glycyrrhizin, a major component in licorice, was found to interfere with steroid metabolism and cause edema and hypertension. The roasting process of licorice modifies the chemical composition and converts glycyrrhizin to glycyrrhetinic acid. The purpose of this study was to examine the anti-carcinogenic effects of the ethanol extract of roasted licorice (EERL) and to identify the active compound in EERL. MATERIALS/METHODS Ethanol and aqueous extracts of roasted and un-roasted licorice were prepared. The active fraction was separated from the methylene chloride (MC)-soluble fraction of EERL and the structure of the purified compound was determined by nuclear magnetic resonance spectroscopy. The anti-carcinogenic effects of licorice extracts and licochalcone A was evaluated using a MTT assay, Western blot, flow cytometry, and two-stage skin carcinogenesis model. RESULTS EERL was determined to be more potent and efficacious than the ethanol extract of un-roasted licorice in inhibiting the growth of DU145 and MLL prostate cancer cells, as well as HT-29 colon cancer cells. The aqueous extracts of un-roasted and roasted licorice showed minimal effects on cell growth. EERL potently inhibited growth of MCF-7 and MDA-MB-231 breast, B16-F10 melanoma, and A375 and A2058 skin cancer cells, whereas EERL slightly stimulated the growth of normal IEC-6 intestinal epithelial cells and CCD118SK fibroblasts. The MC-soluble fraction was more efficacious than EERL in inhibiting DU145 cell growth. Licochalcone A was isolated from the MC fraction and identified as the active compound of EERL. Both EERL and licochalcone A induced apoptosis of DU145 cells. EERL potently inhibited chemically-induced skin papilloma formation in mice. CONCLUSIONS Non-polar compounds in EERL exert potent anti-carcinogenic effects, and that roasted rather than un-roasted licorice should be favored as a cancer preventive agent, whether being used as an additive to food or medicine preparations.
    Nutrition research and practice 06/2014; 8(3):257-66. DOI:10.4162/nrp.2014.8.3.257 · 1.44 Impact Factor
  • Source
    • "The high expression of genes encoding proteins containing the Pfam domain " Heavy metal transport/detoxification protein (PF00403) " in our EST data is consistent with the efficacy of Glycyrrhiza uralensis extracts in detoxifying the adverse reactions (cardiotoxicity, nausea, vomiting, diarrhea and hepatotoxicity) of most effective anti-cancer drugs and in broadening the narrow therapeutic windows of those anti-cancer drugs (Choi et al. 2008; Lin et al. 2009). Even though several investigators have reported that glycyrrhizin-free extracts from Glycyrrhiza uralensis, could be used to detoxify those adverse effects, many questions about the genes involved in the detoxification of metabolic products in this organism remain unanswered (Choi et al. 2008). In this regard, our EST data list of highly expressed genes encoding proteins containing heavy metal transport/detoxification domains points to candidate genes whose molecular functions may give insight into the molecular mechanisms underlying such detoxification and for widening the narrow therapeutic windows of some pharmaceuticals. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Glycyrrhiza uralensis Fisch is an important medicinal plant used not only as a natural sweetener but also for a variety of pharmaceutical applications. Even though there have been previous reports of genes putatively associated with the biosynthesis of the sweet compound glycyrrhizin, the absence of genomic information and the insufficient transcriptomic data for this plant still hinder sufficient insight into the causative genes underlying the pharmaceutical and culinary applications of Glycyrrhiza uralensis Fisch. In this study, we sequenced 5,276 ESTs from Glycyrrhiza uralensis Fisch, established 2,353 unique sequences based on clustering and performed comparative analysis of them. Of the 2,353 unique sequences, we found homologs and orthologs for 1,499 of them with similarity searches against the non-redundant protein database at NCBI using the BLASTX algorithm and against the InterPro database using hidden Markove model (HMM) methods. We have functionally classified 749 unique sequences using Gene Ontology (GO) terms, mapped pathways for 248 unique sequences with the Kyoto Encyclopedia of Genes and Genomes (KEGG) and predicted 30 secreted proteins. Based on their expression levels, we have identified genes encoding a novel beta-D-xylosidase, glutathione-S-transferase and arabinogalactan protein 16 that may function in the glycyrrhizin biosynthesis, anti-tumor activity and detoxifying activity of this very promising medicinal plant. Furthermore, the EST sequence information described in this paper could be a valuable resource for future scientific research projects on this plant, including genome sequencing and annotation and genetic diversity as well as functional genomics and molecular functional studies. KeywordsGlycyrrhiza uralensis Fisch–glycyrrhizin–Pharmaceutical application–EST
    Plant Molecular Biology Reporter 12/2011; 29(4):814-824. DOI:10.1007/s11105-011-0290-9 · 1.66 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Previously, we prepared a hexane/ethanol extract of Glycyrrhiza uralensis (HEGU) containing undetectable amounts of glycyrrhizin, which is known to induce hypertension. This study assessed the effect of HEGU on inflammatory responses in lipopolysaccharide (LPS)-treated Raw264.7 macrophages and in mouse skin treated with 12-O-tetradecanoylphorbol-13-acetate. In the LPS-stimulated macrophages, HEGU (0–2 μg/ml) reduced nitric oxide (NO) release and the protein expression and transcriptional activity of inducible NO synthase (iNOS). HEGU reduced prostaglandin E2 release and phospholipase A2 transcripts. HEGU reduced the secretion and mRNA levels of tumour necrosis factor-α, interleukin (IL)-6, and IL-1β. HEGU prevented IκBα degradation, p65 nuclear translocation, NFκB DNA binding and transcriptional activities. Additionally, dehydroglyasperin C, isolated from HEGU, reduced NO production, iNOS expression, and NFκB transcriptional activity. In the mouse inflammation model, HEGU suppressed skin swelling and iNOS and cyclooxygenase-2 expression. These results indicate that HEGU exerts powerful anti-inflammatory effects, probably mediated via the inhibition of NFκB signalling.
    Food Chemistry 08/2010; 121(4-121):959-966. DOI:10.1016/j.foodchem.2010.01.027 · 3.39 Impact Factor
Show more