Effects of acute renal failure induced by uranyl nitrate on the pharmacokinetics of liquiritigenin and its two glucuronides, M1 and M2, in rats

Chemical Profile Assessment and Potential Bioactive Component Screening of a Chinese Patent Herbal Drug Yi-Shen-Hua-Shi Granule

Yi-Shen-Hua-Shi (YSHS) Granule is a well-known patented herbal drug for treating chronic glomerulonephritis (CGN) in China. Its chemical compositions and anti-CGN components are not fully understood. This study aimed to establish the chemical profile and to identify the anti-CGN components of YSHS Granule. For these purposes, a HPLC-Q-TOF-MS/MS method was developed. A total of 105 peaks were detected in the mass spectrum of the Granule. Of these, 99 compounds were tentatively identified as terpenoids, flavonoids, coumarins, alkaloids, phenols, and other types of compounds, and 15 were further identified with reference substances. To screen bioactive compounds, a cell membrane immobilized chromatography (CMIC) method was used. Lipopolysaccharide (LPS)-challenged rat glomerular mesangial cells (HBZY-1) were incubated with YSHS Granule (100 μg/mL), and the binding components to the cell membrane were extracted and analyzed using the established HPLC-Q-TOF-MS/MS method. Seven potential bioactive components that bound to HBZY-1 cell membranes were detected and identified as calycosin-7- O-β-D-glucoside, 6-gingerol, naringin, ginsenoside Re, poncirin, liquiritigenin, and isoliquiritigenin. The outcomes of the present study provide a chemical basis for clinical use of the Granule in managing CGN, and provide quality control markers for the Granule’s production and use.

Liquiritigenin inhibits IL-1β-induced inflammation and cartilage matrix degradation in rat chondrocytes

Osteoarthritis (OA) is an age-related arthropathy which has been considered to be associated with inflammatory damage and cartilage degradation. Liquiritigenin (LG), the main bioactive component of the rhizomes of Glycyrrhiza uralensis, has exhibited promising anti-inflammatory and anti-oxidative potential in numerous inflammatory diseases. However, the effects of LG on OA remain unclear. In this study, the therapeutic effects as well as the underlying mechanisms of LG on interleukin-1β (IL-1β)-treated rat chondrocytes had been investigated. Our results showed that LG could inhibit the IL-1β-induced expression of nitic oxide (NO) and prostaglandin E₂ (PGE₂). In consist with these findings, the IL-1β-induced production of inducible nitic oxide synthase (iNOS) and cyclooxygenase-2 (COX2) could also be decreased by LG. Meanwhile, LG could suppress the IL-1β-induced upregulation of cartilage matrix catabolic enzymes including aggrecanase-2 (ADAMTS5) and matrix metalloproteinases (MMPs). Besides, the IL-1β-induced degradation of collagen II and aggrecan could be alleviated by LG. Moreover, LG prevented cartilage damage in IL-1β-treated rat cartilage explants. Mechanistically, LG functioned by inhibiting mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) pathways activation. In general, this study reveals the anti-inflammatory properties of LG on IL-1β-treated rat chondrocytes and the possible mechanisms behind it, which may provide new ideas for OA therapy.

UDP-glucuronosyltransferases (UGTs) and their related metabolic cross-talk with internal homeostasis: A systematic review of UGT isoforms for precision medicine

UDP-glucuronosyltransferases (UGTs) are the primary phase II enzymes catalyzing the conjugation of glucuronic acid to the xenobiotics with polar groups for facilitating their clearance. The UGTs belong to a superfamily that consists of diverse isoforms possessing distinct but overlapping metabolic activity. The abnormality or deficiency of UGTs in vivo is highly associated with some diseases, efficacy and toxicity of drugs, and precisely therapeutic personality. Despite the great effects and fruitful results achieved, to date, the expression and functions of individual UGTs have not been well clarified, the inconsistency of UGTs is often observed in human and experimental animals, and the complex regulation factors affecting UGTs have not been systematically summarized. This article gives an overview of updated reports on UGTs involving the various regulatory factors in terms of the genetic, environmental, pathological, and physiological effects on the functioning of individual UGTs, in turn, the dysfunction of UGTs induced disease risk and endo- or xenobiotic metabolism-related toxicity. The complex cross-talk effect of UGTs with internal homeostasis is systematically summarized and discussed in detail, which would be of great importance for personalized precision medicine.

Stereospecific pharmacokinetic characterization of liquiritigenin in the rat

Liquiritigenin is a chiral flavonoid present in licorice and other medicinal plants. The nature of its biological fate with respect to the individual enantiomers has not been examined. In this study, we characterize, for the first time, the stereoselective pharmacokinetics of liquiritigenin. Liquiritigenin was intravenously (20 mg/kg) and orally (50 mg/kg) administered to male Sprague-Dawley rats (n = 4 per route of administration). Concentrations in serum and urine were characterized via stereospecific reversed-phase, isocratic HPLC method with UV detection. Serum concentrations were quantified but rapidly fell to undetectable levels. S-liquiritigenin showed a short half-life (0.25-0.54 h), while a better estimation of half-life (26-77 h) and other pharmacokinetic parameters was observed using urinary data. The flavonoid is predominantly excreted via non-renal routes (f_e values of 0.16-3.46 %), and undergoes rapid and extensive phase II metabolism. Chiral differences in the chemical structure of the compound result in some pharmacokinetic differences. Serum concentrations rapidly declined, making modeling difficult. S-liquiritigenin showed an increased urinary half-life.

Antihyperuricemic effect of liquiritigenin in potassium oxonate-induced hyperuricemic rats

The aim is to investigate the anti-hyperuricemic and renal protective effects of liquiritigenin in potassium oxonate-induced hyperuricemic rats. Hyperuricemia in rats was induced were induced with potassium oxonate (250mg/kg) intragastrically for 7 days, and liquiritigenin (20, 40mg/kg) and allopurinol (5mg/kg) were daily administrated to the rats orally 1h after the potassium oxonate exposure. Liquiritigenin significantly reversed the elevated productions of uric acid in serum and urine and pro-inflammation cytokines in serum and kidney, which shown that liquiritigenin has renal protective effects. Histological study shows that liquiritigenin inhibited severe necrosis and inflammatory cell infiltration in potassium oxonate-treated rats. Furthermore, liquiritigenin mediated the activities of aquaporins 4 (AQP4), and regulated the activation of NF-κB p65 and the degradation of IκBα. Finally, significant increases of nod-like receptor protein 3 (NLRP3) inflammasome, apoptosis-associated speck-like protein adaptor (ASC) adaptor and cleaved caspased-1 were restored by liquiritigenin. Therefore, liquiritigenin might improve renal inflammation by suppressing renal AQP4/NF-κB/IκBα and NLRP3 inflammasome activation in hyperuricemic rats.

Evaluation of estrogenic activity of licorice species in comparison with hops used in botanicals for menopausal symptoms

The increased cancer risk associated with hormone therapies has encouraged many women to seek non-hormonal alternatives including botanical supplements such as hops (Humulus lupulus) and licorice (Glycyrrhiza spec.) to manage menopausal symptoms. Previous studies have shown estrogenic properties for hops, likely due to the presence of 8-prenylnarigenin, and chemopreventive effects mainly attributed to xanthohumol. Similarly, a combination of estrogenic and chemopreventive properties has been reported for various Glycyrrhiza species. The major goal of the current study was to evaluate the potential estrogenic effects of three licorice species (Glycyrrhiza glabra, G. uralensis, and G. inflata) in comparison with hops. Extracts of Glycyrrhiza species and spent hops induced estrogen responsive alkaline phosphatase activity in endometrial cancer cells, estrogen responsive element (ERE)-luciferase in MCF-7 cells, and Tff1 mRNA in T47D cells. The estrogenic activity decreased in the order H. lupulus > G. uralensis > G. inflata > G. glabra. Liquiritigenin was found to be the principle phytoestrogen of the licorice extracts; however, it exhibited lower estrogenic effects compared to 8-prenylnaringenin in functional assays. Isoliquiritigenin, the precursor chalcone of liquiritigenin, demonstrated significant estrogenic activities while xanthohumol, a metabolic precursor of 8-prenylnaringenin, was not estrogenic. Liquiritigenin showed ERβ selectivity in competitive binding assay and isoliquiritigenin was equipotent for ER subtypes. The estrogenic activity of isoliquiritigenin could be the result of its cyclization to liquiritigenin under physiological conditions. 8-Prenylnaringenin had nanomolar estrogenic potency without ER selectivity while xanthohumol did not bind ERs. These data demonstrated that Glycyrrhiza species with different contents of liquiritigenin have various levels of estrogenic activities, suggesting the importance of precise labeling of botanical supplements. Although hops shows strong estrogenic properties via ERα, licorice might have different estrogenic activities due to its ERβ selectivity, partial estrogen agonist activity, and non-enzymatic conversion of isoliquiritigenin to liquiritigenin.