Xiaoxv Dong

Emodin: A Review of its Pharmacology, Toxicity and Pharmacokinetics

Emodin is a natural anthraquinone derivative that occurs in many widely used Chinese medicinal herbs, such as Rheum palmatum, Polygonum cuspidatum and Polygonum multiflorum. Emodin has been used as a traditional Chinese medicine for over 2000 years and is still present in various herbal preparations. Emerging evidence indicates that emodin possesses a wide spectrum of pharmacological properties, including anticancer, hepatoprotective, antiinflammatory, antioxidant and antimicrobial activities. However, emodin could also lead to hepatotoxicity, kidney toxicity and reproductive toxicity, particularly in high doses and with long‐term use. Pharmacokinetic studies have demonstrated that emodin has poor oral bioavailability in rats because of its extensive glucuronidation. This review aims to comprehensively summarize the pharmacology, toxicity and pharmacokinetics of emodin reported to date with an emphasis on its biological properties and mechanisms of action. Copyright

Types, principle, and characteristics of tandem high-resolution mass spectrometry and its applications

Tandem high-resolution mass spectrometry (THRMS) is an analytical technique that has arisen in recent years and is now widely used in pharmaceutical research and development (RD for example, for the identification of constituents in herbs and formulae, pharmacokinetics, omics, and drug degradation), food safety, environmental contamination and other research fields. Time of Flight (TOF) and Orbitrap are the most widely used mass analysers in THRMS, and the technical specifications vary among the different types of THRMS and even among the different manufacturers for a given type of analyser. In this article, we review the principle and functional characteristics of different types or models for THRMS and provide a brief description of its applications in the medical research, food safety, and environmental protection fields.

Induction of Apoptosis in HepaRG Cell Line by Aloe-Emodin through Generation of Reactive Oxygen Species and the Mitochondrial Pathway

Background/Aims: Aloe-emodin (1,8-dihydroxy-3-hydroxymethyl-anthraquinone), an anthraquinone active compounds, is isolated from some traditional medicinal plants such as Rheum palmatum L. and Cassia occidentalis, which induce hepatotoxicity in rats. The aim of this study was to determine potential cytotoxic effects of aloe-emodin on HepaRG cells and to define the underlying mechanism. Methods: MTT was used to evaluate cell viability. Apoptotic cell death was analyzed via Annexin V-FITC/PI double staining. Intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were determined by flow cytometry, while the expression of apoptosis-related proteins was determined by Western blot analysis. Results: Treatment with aloe-emodin significantly reduced cell viability and induced apoptosis in HepaRG cells in a dose- and time-dependent manner. It provoked ROS generation and depolarization of MMP in HepaRG cells when compared with controls. Aloe-emodin dose-dependently increased release of mitochondrial cytochrome c, and levels of Fas, p53, p21, Bax/Bcl-2 ratio, as well as activation of caspase-3, caspase-8, caspase-9, and subsequent cleavage of poly(ADP-ribose)polymerase (PARP). It also induced S-phase cell cycle arrest by increasing the expression of p21 and cyclin E proteins while significantly decreasing the expression of cyclin A and CDK2. Conclusion: These results suggest that aloe-emodin inhibits cell proliferation and induces apoptosis in HepaRG cells, most probably through a mechanism involving both Fas death pathway and the mitochondrial pathway by generation of ROS. These findings underscore the need for risk assessment of human exposure to aloe-emodin.

Radix Bupleuri: A Review of Traditional Uses, Botany, Phytochemistry, Pharmacology, and Toxicology

Radix Bupleuri (Chaihu) has been used as a traditional medicine for more than 2000 years in China, Japan, Korea, and other Asian countries. Phytochemical studies demonstrated that this plant contains essential oils, triterpenoid saponins, polyacetylenes, flavonoids, lignans, fatty acids, and sterols. Crude extracts and pure compounds isolated from Radix Bupleuri exhibited various biological activities, such as anti-inflammatory, anticancer, antipyretic, antimicrobial, antiviral, hepatoprotective, neuroprotective, and immunomodulatory effects. However, Radix Bupleuri could also lead to hepatotoxicity, particularly in high doses and with long-term use. Pharmacokinetic studies have demonstrated that the major bioactive compounds (saikosaponins a, b2, c, and d) were absorbed rapidly in rats after oral administration of the extract of Radix Bupleuri. This review aims to comprehensively summarize the traditional uses, botany, phytochemistry, pharmacology, toxicology, and pharmacokinetics of Radix Bupleuri reported to date with an emphasis on its biological properties and mechanisms of action.

Chemical Constituents from Daphne giraldii Nitsche and Their Contents Simultaneous Determination by HPLC

Daphne giraldii Nitsche (Thymelaeaceae) is widely distributed in the Chinese provinces of Shaanxi, Gansu, and Qinghai, which has been used in Chinese folk medicine to treat ache and rheumatism. Pharmacologic tests have revealed that the plant has anti-inflammatory, analgesic, and anticancer activities. However, there is still not enough systemic investigation on the chemical constituents and the method for the contents simultaneous determination in D. giraldii. Therefore, the isolation and characterization of the compounds from the stem barks of this plant were reported. Moreover, a facile, accurate, and reliable method has been developed and validated for their simultaneous determination using HPLC-DAD.

Simultaneous Determination and Pharmacokinetic Study of Quercetin, Luteolin, and Apigenin in Rat Plasma after Oral Administration of Matricaria chamomilla L. Extract by HPLC-UV

A simple and sensitive HPLC-UV method has been developed for the simultaneous determination of quercetin, luteolin, and apigenin in rat plasma after oral administration of Matricaria chamomilla L. extract. The flow rate was set at 1.0 ml/min and the detection wavelength was kept at 350 nm. The calibration curves were linear in the range of 0.11–11.36 μg/ml for quercetin, 0.11–11.20 μg/ml for luteolin, and 0.11–10.60 μg/ml for apigenin, respectively. The intraday and interday precisions (RSD) were less than 8.32 and 8.81%, respectively. The lower limits of quantification (LLOQ) of the three compounds were 0.11 μg/ml. The mean recoveries for quercetin, luteolin, and apigenin were 99.11, 95.62, and 95.21%, respectively. Stability studies demonstrated that the three compounds were stable in the preparation and analytical process. The maximum plasma concentration (Cmax) was 0.29 ± 0.06, 3.04 ± 0.60, and 0.42 ± 0.10 μg/ml, respectively. The time to reach the maximum plasma concentration (Tmax) was 0.79 ± 0.25, 0.42 ± 0.09, and 0.51 ± 0.13 h, respectively. The validated method was successfully applied to investigate the pharmacokinetics study of quercetin, luteolin, and apigenin in rat plasma after oral administration of M. chamomilla extract.

Aloe‐emodin Induces Apoptosis in Human Liver HL‐7702 Cells through Fas Death Pathway and the Mitochondrial Pathway by Generating Reactive Oxygen Species

Aloe‐emodin (1,8‐dihydroxy‐3‐hydroxymethyl‐anthraquinone) is one of the primary active compounds in total rhubarb anthraquinones isolated from some traditional medicinal plants such as Rheum palmatum L. and Cassia occidentalis, which induce hepatotoxicity in rats. Thus, the aim of this study was to determine the potential cytotoxic effects and the underlying mechanism of aloe‐emodin on human normal liver HL‐7702 cells. The CCK‐8 assays demonstrated that aloe‐emodin decreased the viability of HL‐7702 cells in a dose‐dependent and time‐dependent manner. Aloe‐emodin induced S and G2/M phase cell cycle arrest in HL‐7702 cells. This apoptosis was further investigated by flow cytometry and nuclear morphological changes by DAPI staining, respectively. Moreover, aloe‐emodin provoked the production of intracellular reactive oxygen species and the depolarization of mitochondrial membrane potential (MMP). Further studies by western blot indicated that aloe‐emodin dose‐dependently up‐regulated the levels of Fas, p53, p21, Bax/Bcl‐2 ratio, and cleaved caspase‐3, ‐8, ‐9, and subsequent cleavage of poly(ADP‐ribose)polymerase (PARP). Taken together, these results suggest that aloe‐emodin inhibits cell proliferation of HL‐7702 cells and induces cell cycle arrest and caspase‐dependent apoptosis via both Fas death pathway and the mitochondrial pathway by generating reactive oxygen species, indicating that aloe‐emodin should be taken into account in the risk assessment for human exposure. Copyright

Cassiae semen: A review of its phytochemistry and pharmacology (Review)

Cassiae semen (Leguminosae), a well-known traditional Chinese medicine, has been used for a number of centuries in areas of Southeast Asia, including Korea, Japan and China. The present review aims to provide updated and comprehensive information, on the botany, phytochemistry and pharmacology of Cassiae semen. The available information on Cassiae semen was collected using several different resources, including classic books on Chinese herbal medicine and a number of scientific databases, including the China Academic Journals full-text database, PubMed, SciFinder, the Web of Science and Science Direct. To date >70 chemical compounds have been isolated from Cassiae semen, and the major components have been determined to be anthraquinones, naphthopyrones and volatile oil. The crude extracts and pure compounds of Cassiae semen have been used as effective agents in preclinical and clinical practice due to their beneficial activities, including antihyperlipidemic, antidiabetic, neuroprotective, hepatoprotective, antibacterial, antioxidant and hypotensive activities. With the body of reported data, it has been suggested that Cassiae semen has convincing medicinal potential. However, the pharmacological mechanisms of the main bioactive compounds and the association between structure and activity require further investigation.

Pharmacokinetics and brain distribution studies of ginsenoside Rd in rats via intranasal administration by LC-MS/MS

Ginsenoside Rd was shown to have protective effects against several injuries and efficient for the treatment of acute ischemic stroke. Some research studies of ginsenoside Rd in the past mainly focused on the pharmacokinetics after intravenous and oral administration. However, we still lack some basic knowledge about the plasma pharmacokinetics and brain distribution of ginsenoside Rd by any other route, such as intranasal administration. It was found that intranasal administration exhibited good brain-targeting. In this study, a sensitive LC-MS/MS method was developed and validated for the determination of ginsenoside Rd in rat plasma and brain tissue. Detection was performed on an ACQUITY UPLC™ BEH C18 column using gradient elution with a flow rate of 0.2 mL min−1. Mass spectrometry was operated in selected reaction monitoring mode using a negative electrospray ionization interface. The method was linear over the concentration range of 1.0–1000 ng mL−1, and the lower limit of quantification was 1.0 ng mL−1 for ginsenoside Rd. The method was validated in terms of specificity, linearity, intra- and inter-day precision (<12.39%), accuracy (within ±10.1%), dilution integrity, recovery, matrix effects and stability, and has been successfully applied to the pharmacokinetic study of ginsenoside Rd in rats after intranasal administration and evaluation of the brain targeting of ginsenoside Rd.

Molecular Mechanisms of Apoptosis in HepaRG Cell Line Induced by Polyphyllin VI via the Fas Death Pathway and Mitochondrial-Dependent Pathway

Polyphyllin VI, which is an active saponin, is mainly isolated from traditional medicinal plant Paris polyphylla, which causes liver damage in rats. In the present study, we aimed to explore the potential cytotoxicity of polyphyllin VI on the growth of HepaRG cells and to determine the molecular mechanism. The results revealed that polyphyllin VI changed cell morphology and induced apoptosis in HepaRG cells. Flow cytometric assay displayed that polyphyllin VI promoted the generation of reactive oxygen species (ROS), depolarized the mitochondrial membrane potential (MMP), and induced S phase cell cycle arrest by decreasing the expression of cyclin A2 and CDK2, while significantly increasing the expression of p21 protein. Polyphyllin VI induced the release of cytochrome c from the mitochondria to the cytosol and activated Fas, caspase-3, -8, -9, and PARP proteins. Pretreatment with NAC and Z-VAD-FMK (ROS scavenger and caspase inhibitor, respectively) on HepaRG cells increased the percentage of viable cells, which indicated that polyphyllin VI induced cell apoptosis through mitochondrial pathway by the generation of ROS and Fas death-dependent pathway. All of the effects are in dose- and time-dependent manners. Taken together, these findings emphasize the necessity of risk assessment to polyphyllin VI and offer an insight into polyphyllin VI-induced apoptosis of HepaRG cells.