neoisoliquiritin and isoliquiritigenin

Honey-processed licorice (HPL) is the roasted product of licorice. It is recorded in the "Shang Han Lun" that licorice has better protection on heart after honey-processed. However, researches regarding its protective effect on the heart and the distribution of HPL in vivo are still limited.. To evaluate the cardio-protection of HPL and explore the law of ten main components distribution in vivo under physiological and pathological conditions for an attempt to clarify the pharmacological substance basis of HPL in treating arrhythmia.. The adult zebrafish arrhythmia model was established by doxorubicin (DOX). Electrocardiogram (ECG) was used to detect the heart rate changes of zebrafish. SOD and MDA assays were used to evaluate oxidative stress levels in the myocardium. HE staining was used to observe the morphological change of myocardial tissues after HPL treatment. The UPLC-MS/MS was adapted to detect the content of ten main components of HPL in heart, liver, intestine, and brain under normal and heart injury conditions.. Heart rate of zebrafish was decreased, the SOD activity was attenuated and MDA content was increased in myocardium after administration of DOX. Moreover, tissue vacuolation and inflammatory infiltration were detected in zebrafish myocardium induced by DOX. HPL could ameliorate heart injury and bradycardia induced by DOX to a certain extent by increasing SOD activity and reducing MDA content. In addition, the study of tissue distribution revealed that the content of liquiritin, isoliquiritin, and isoliquiritigenin in the heart was higher in the presence of arrhythmias than those in the normal condition. Under pathological conditions, the heart highly exposed to these three components could elicit anti-arrhythmic effects by regulating immunity and oxidation.. These findings indicate that the HPL is protective against heart injury induced by DOX, and its effect is associated with the alleviation of oxidative stress and tissue injury. And the cardioprotective effect of HPL under pathological conditions may be related to the high distribution of liquiritin, isoliquiritin, and isoliquiritigenin in heart tissue. This study provides an experimental basis for the cardioprotective effects and tissue distribution of HPL.

Topics: Animals; Anti-Arrhythmia Agents; Antioxidants; Chromatography, Liquid; Doxorubicin; Glycyrrhiza; Heart Injuries; Honey; Oxidative Stress; Superoxide Dismutase; Tandem Mass Spectrometry; Tissue Distribution; Zebrafish

Isoliquiritigenin (ILG) and isoliquiritin (ILQ), two kinds of major flavonoids in licorice, are biological active substances with antioxidant, anti-inflammatory, and tumor-suppressive effects. However, their in vivo metabolites, possible material basis of this two licorice chalcones for the treatment of diseases, have not been studied completely. To determine the metabolism of ILG and ILQ, after oral administration of 100 mg/kg/day of these compounds for consecutive 8 days, the metabolites of these two licorice chalcones in mice plasma, urine, feces, and bile were determined using liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry in this study. The structures of those metabolites were tentatively identified according to their fragment pathways, accurate masses, characteristic product ions, metabolism law, and reference standards-matching. As a result, a total of 25 and 29 metabolites of ILG and ILQ were identified, respectively. Seven main metabolic pathways, oxidation and reduction, deglycosylation and glycosylation, dehydroxylation and hydroxylation, demethoxylation and methoxylation, acetylation, glucuronidation, and sulfation, were summarized to tentatively explain how the metabolites were biologically transformed. These results provide the important information on the metabolism of ILG and ILQ, which may be helpful for the further research of their pharmacological mechanism.

Topics: Administration, Oral; Animals; Bile; Chalcone; Chalcones; Chromatography, Liquid; Feces; Glucosides; Glycyrrhiza; Mice; Mice, Inbred C57BL; Tandem Mass Spectrometry

Licorice is one of the most common herbs in traditional Chinese medicine, and classified as top\ grade in Shen Nong Ben Cao Jing. There are three different original plants of licorice stipulated in Chinese\ Pharmacopeia, Glycyrrhiza uralensis Fisch., Glycyrrhiza glabra L., and Glycyrrhiza inflata Bat. However,\ previous investigation showed that the pharmacodynamic effects of the three licorices were quite different. It is\ very difficult to identify them by the classical identification methods. In order to establish a fast and effective\ identification method, we collected 240 licorice plants from 21 populations of 7 provinces, and amplified their\ ITS and psbA-trnH sequences. ITS sequences with a full length of 616 bp and psbA-trnH sequences with a full\ length of 389 bp were obtained separately. Using DNAMAN to analyze these sequences, 4 variable sites were\ found in ITS sequences and 2 ITS haplotypes were determined, and 3 variable sites were found in psbA-trnH\ sequences and 4 psbA-trnH haplotypes were determined. With the combination analysis of ITS and psbA-trnH\ sequences, the molecular identification method of original licorice was established. Using this method, 40\ samples of licorice slices collected from 4 main herbal material markets in China were identified successfully.\ Furthermore, the contents of 2 triterpenes, 18α-glycyrrhizic acid and 18β-glycyrrhizic acid, and 4 flavonoids,\ liquiritin, isoliquiritin, liquiritigenin, and isoliquiritigenin in these licorice pieces were examined by HPLC and\ the results were analyzed using SPSS 21.0. This study provides a new method in identification of licorice,\ which may serve as a guideline for quality control of licorice slices.

Topics: Chalcone; Chalcones; China; Chromatography, High Pressure Liquid; Drugs, Chinese Herbal; Flavanones; Flavonoids; Glucosides; Glycyrrhiza; Glycyrrhiza uralensis; Glycyrrhizic Acid; Triterpenes

A specific and sensitive HPLC-MS/MS method was developed and validated for the simultaneously quantification of isoliquiritigenin (ISL) and neoisoliquiritin (NIS) in rat plasma by oral administration. Analytes were analyzed on an Agilent 6460 LC-MS/MS system (Agilent, USA) using an Agilent Zorbax SB-C18 column (4.6 × 150 mm, 5 μm). Gradient elution was applied for the analyte separation using a mobile phase composed of 0.1% formic acid aqueous solution and methanol at a flow rate of 1.0 mL/min with a total running time of 12 min. The calibration curves for ISL and NIS showed good linearity in the concentrations ranging from 0.001 to 4.000 μg/mL with correlation coefficients >0.998. The precision, accuracy, recovery and stability were deemed acceptable. The method was applied to the pharmacokinetics study of ISL and NIS in rats by single and combination administration. The result showed that Cmax and AUC0→t of ISL were markedly increased from 0.53 to 1.20 μg/mL, and from 69.63 to 200.74 min μg/mL by combination administration. The mean t1/2 value was also prolonged from 64.55 to 203.74 min in the combination group. These results indicated that NIS may have been metabolized to ISL which increased the absorption and extended the elimination of ISL. However, little difference was found for NIS pharmacokinetics parameters between single NIS and the combination group, which suggested that there was no significant biotransformation of ISL to NIS. Copyright © 2015 John Wiley & Sons, Ltd.

Topics: Animals; Chalcone; Chalcones; Chromatography, High Pressure Liquid; Glucosides; Rats; Tandem Mass Spectrometry

Liquiritigenin (LQG), isoliquiritin (ILQ) and isoliquiritigenin (ILG) are flavonoids derived from liquorice and all possess a similar chemical structural backbone. In the current study, we found that ILQ and ILG had suppressive effects on lipopolysaccharide (LPS)-induced inflammatory responses in murine macrophage by suppressing the iNOS and COX-2 proteins and mRNA expression. A mechanistic study indicated that the effect was associated with an induction of antioxidant and detoxification enzymes, including UGT1A1, NQO1, and heme oxygenase-1 (HO-1) mRNA expression. The regulator of these enzymes, nuclear factor-erythroid 2-related factor 2 (Nrf2), which plays a critical role in LPS-induced inflammatory responses, could be activated by ILQ and ILG. Additionally, ILQ and ILG promoted Nrf2 signaling activation by inhibiting the Kelch-like ECH-associated protein 1 (Keap1) and increasing Nrf2 translocation, inducing the expression of these antioxidant enzymes. We further found that ILQ and ILG induced HO-1 expression independent of Nrf2 expression. With respect to the effect of these compounds on NF-κB signaling, ILG was found to markedly inhibit IκBα degradation and phosphorylation, while LQG and ILQ had no significant effects. These results indicate that there are correlations between the anti-inflammatory responses and the chemical structural properties of these flavonoids.

Topics: Animals; Anti-Inflammatory Agents; Cell Line; Chalcone; Chalcones; Cyclooxygenase 2; Flavanones; Glucosides; Glycyrrhiza; HEK293 Cells; Heme Oxygenase-1; Hep G2 Cells; Humans; Lipopolysaccharides; Macrophage Activation; Mice; NF-E2-Related Factor 2; Nitric Oxide Synthase Type II; RNA, Messenger; Up-Regulation

Liquiritin, isoliquiritin and isoliquirigenin are the active polyphenols present in Glycyrrhiza uralensis which has been used for the treatment of cancer and its complications. The present study was conducted to evaluate the cytotoxicity and antitumor activity of liquiritin, isoliquiritin and isoliquirigenin on human non-small lung cancer cells including apoptosis-induction, inhibition of apoptotic pathways and to explore the underlying mechanism. Lactate dehydrogenase assays, FITC Annexin V staining assay were performed to evaluate cellular cytotoxicity and apoptosis activity. The results showed that pretreatment with these polyphenols induced apoptosis in A549 cells. Liquiritin, isoliquiritin and isoliquirigenin significantly increased cytotoxicity of, and upregulated p53 and p21 and downregulated the apoptotic pathways. Furthermore, it inhibited cell cycle at the G2/M phase. Western blot analysis showed it significantly decreased the protein expression of PCNA, MDM2, p-GSK-3β, p-Akt, p-c-Raf, p-PTEN, caspase-3, pro-caspase-8, pro-caspase-9 and PARP, Bcl-2 in a concentration-dependent manner while the protein expression of p53, p21 and Bax was increased. In addition, Akt pathway was downregulated. These findings suggest that liquiritin, isoliquiritin and isoliquirigenin inhibited the p53-dependent pathway and showed crosstalk between Akt activities. These active polyphenols can be an alternative agent for the treatment of lung cancer.

Topics: Aldehyde Reductase; Apoptosis; Carcinoma, Non-Small-Cell Lung; Caspase 3; Caspase 7; Cell Line, Tumor; Cell Survival; Chalcone; Chalcones; Cyclin-Dependent Kinase Inhibitor p21; Enzyme Activation; Enzyme Inhibitors; Flavanones; Glucosides; Glycyrrhiza uralensis; Humans; L-Lactate Dehydrogenase; Lung Neoplasms; M Phase Cell Cycle Checkpoints; Plant Extracts; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Signal Transduction; Tumor Suppressor Protein p53

In this study, the anti-inflammatory effects of flavonoids isolated from the roots of Glycyrrhiza uralensis (Leguminosae), namely, isoliquiritin (the glycoside of isoliquirigenin) and isoliquiritigenin (the aglycone of isoliquiritin) were evaluated on lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. Isoliquiritigenin (ILG) more potently inhibited LPS-induced nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production than isoliquiritin (ILT). Consistent with these findings, ILG reduced the LPS-induced expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in a concentration-dependent manner, as determined by Western blotting and RT-PCR, respectively. In addition, the release of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), and the mRNA expression levels of these cytokines were reduced by ILG in a dose-dependent manner. Moreover, ILG attenuated the LPS-induced DNA binding activity and the transcription activity of nuclear factor-kappa B (NF-kappaB), and this was associated with a decrease in inhibitory kappa B-alpha (IkappaB-alpha) phosphorylation and in the subsequent blocking of p65 and p50 protein translocations to the nucleus. Furthermore, ILG suppressed the phosphorylations of IkappaB kinase (IKK), ERK1/2, and p38, whereas the phosphorylation of JNK1/2 was unaffected. These results suggest that the anti-inflammatory properties of ILG are caused by iNOS, COX-2, TNF-alpha, and IL-6 down-regulation due to NF-kappaB inhibition via the suppression of IKK, ERK1/2 and p38 phosphorylation in RAW 264.7 cells.

Topics: Active Transport, Cell Nucleus; Animals; Anti-Inflammatory Agents; Blotting, Western; Cell Line; Cell Survival; Chalcone; Chalcones; Cyclooxygenase 2; Dinoprostone; Dose-Response Relationship, Drug; Down-Regulation; Gene Expression Regulation, Enzymologic; Glucosides; Glycyrrhiza uralensis; I-kappa B Proteins; Interleukin-6; Lipopolysaccharides; Macrophages; Mice; Mitogen-Activated Protein Kinases; NF-kappa B; NF-KappaB Inhibitor alpha; Nitric Oxide; Nitric Oxide Synthase Type II; Phosphorylation; Plant Roots; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Signal Transduction; Transcription, Genetic; Transfection; Tumor Necrosis Factor-alpha