Isoliquiritigenin, an Orally Available Natural FLT3 Inhibitor from Licorice, Exhibits Selective Anti-Acute Myeloid Leukemia Efficacy In Vitro and In Vivo.

Licorice is a medicinal herb widely used to treat inflammation-related diseases in China. Isoliquiritigenin (ISL) is an important constituent of licorice and possesses multiple bioactivities. In this study, we examined the selective anti-AML (acute myeloid leukemia) property of ISL via targeting FMS-like tyrosine kinase-3 (FLT3), a certified valid target for treating AML. In vitro, ISL potently inhibited FLT3 kinase, with an IC50 value of 115.1 ± 4.2 nM, and selectively inhibited the proliferation of FLT3-internal tandem duplication (FLT3-ITD) or FLT3-ITD/F691L mutant AML cells. Moreover, it showed very weak activity toward other tested cell lines or kinases. Western blot immunoassay revealed that ISL significantly inhibited the activation of FLT3/Erk1/2/signal transducer and activator of transcription 5 (STAT5) signal in AML cells. Meanwhile, a molecular docking study indicated that ISL could stably form aromatic interactions and hydrogen bonds within the kinase domain of FLT3. In vivo, oral administration of ISL significantly inhibited the MV4-11 flank tumor growth and prolonged survival in the bone marrow transplant model via decreasing the expression of Ki67 and inducing apoptosis. Taken together, the present study identified a novel function of ISL as a selective FLT3 inhibitor. ISL could also be a potential natural bioactive compound for treating AML with FLT3-ITD or FLT3-ITD/F691L mutations. Thus, ISL and licorice might possess potential therapeutic effects for treating AML, providing a new strategy for anti-AML.

Diverse Pharmacological Activities and Potential Medicinal Benefits of Geniposide.

Geniposide is a well-known iridoid glycoside compound and is an essential component of a wide variety of traditional phytomedicines, for example, Gardenia jasminoides Elli (Zhizi in Chinese), Eucommia ulmoides Oliv. (Duzhong in Chinese), Rehmannia glutinosa Libosch. (Dihuang in Chinese), and Achyranthes bidentata Bl. (Niuxi in Chinese). It is also the main bioactive component of Gardeniae Fructus, the dried ripe fruit of Gardenia jasminoides Ellis. Increasing pharmacological evidence supports multiple medicinal properties of geniposide including neuroprotective, antidiabetic, hepatoprotective, anti-inflammatory, analgesic, antidepressant-like, cardioprotective, antioxidant, immune-regulatory, antithrombotic, and antitumoral effects. It has been proposed that geniposide may be a drug or lead compound for the prophylaxis and treatment of several diseases, such as Alzheimer's disease, Parkinson's disease, diabetes and diabetic complications, ischemia and reperfusion injury, and hepatic disorders. The aim of the present review is to give a comprehensive summary and analysis of the pharmacological properties of geniposide, supporting its use as a medicinal agent.

Iridoids from Valeriana jatamansi induce autophagy-associated cell death via the PDK1/Akt/mTOR pathway in HCT116 human colorectal carcinoma cells.

Chlorovaltrates U-W (1-3), three previously undescribed iridoids, together with four known analogues were isolated from the roots of Valeriana jatamansi. Their structures were elucidated by means of spectroscopic analyses (HRESIMS, NMR). The cytotoxicity of all isolates was evaluated. Compounds 5-7 exhibited selective cytotoxicity against HCT116 cells, with IC50 values of 9.3, 1.7 and 2.2 µM, respectively. The preliminary mechanistic study revealed that, the cytotoxicity effect of 6 was attributed to Akt/mTOR activation blockade via inhibition of PDK1 phosphorylation. Meanwhile, compound 6 could induce autophagosome formation in HCT116 cells via suppressing its downstream Akt/mTOR. These findings show that compound 6 could be of great importance to the development of anti-colon cancer agents.

Building an octaploid genome and transcriptome of the medicinal plant Pogostemon cablin from Lamiales.

The Lamiales order presents highly varied genome sizes and highly specialized life strategies. Patchouli, Pogostemon cablin (Blanco) Benth. from the Lamiales, has been widely cultivated in tropical and subtropical areas of Asia owing to high demand for its essential oil. Here, we generated ~681 Gb genomic sequences (~355X coverage) for the patchouli, and the assembled genome is ~1.91 Gb and with 110,850 predicted protein-coding genes. Analyses showed clear evidence of whole-genome octuplication (WGO) since the pan-eudicots γ triplication, which is a recent and exclusive polyploidization event and occurred at ~6.31 million years ago. Analyses of TPS gene family showed the expansion of type-a, which is responsible for the synthesis of sesquiterpenes and maybe highly specialization in patchouli. Our datasets provide valuable resources for plant genome evolution, and for identifying of genes related to secondary metabolites and their gene expression regulation.

Crotonoside exhibits selective post-inhibition effect in AML cells via inhibition of FLT3 and HDAC3/6.

Targeted therapies for the treatment of acute myeloid leukemia (AML), specifically the FLT3 inhibitors, have shown promising results. Nevertheless, it is very unlikely that inhibitors which target a single pathway will provide long-term disease control. Here, we report the characterization of crotonoside, a natural product extracted from Chinese medicinal herb, Croton, for the treatment of AML via inhibition of FLT3 and HDAC3/6. In vitro, crotonoside exhibited selective inhibition in AML cells. In vivo, crotonoside treatment at 70 and 35 mg/kg/d produced significant AML tumor inhibition rates of 93.5% and 73.6%, respectively. Studies on the anti-AML mechanism of crotonoside demonstrated a significant inhibition of FLT3 signaling, cell cycle arrest in G0/G1 phase, and apoptosis. In contrast to classic FLT3 inhibitor; sunitinib, crotonoside was able to selectively suppress the expression of HDAC3 and HDAC6 without altering the expression of other HDAC isoforms. Inhibitors of HDAC3 and HDAC6; RGFP966 and HPOB, respectively, also exhibited selective inhibition in AML cells. Furthermore, we established novel signaling pathways including HDAC3/NF-κB-p65 and HDAC6/c-Myc besides FLT3/c-Myc which are aberrantly regulated in the progression of AML. In addition, crotonoside alone or the combination of sunitinib/RFP966/HPOB exhibited a significant post-inhibition effect in AML cells by the inhibition of FLT3 and HDAC3/6. Inhibitors targeting the FLT3 and HDAC3/6 might provide a more effective treatment strategy for AML. Taken together, the present study suggests that crotonoside could be a promising candidate for the treatment of AML, and deserves further investigations.

The Influence of Aconitum carmichaelii Debx. on the Pharmacokinetic Characteristics of Main Components in Rheum palmatum L.

Rhei Radix et Rhizoma was one of the commonly used traditional Chinese medicines, and the compatibility of Rhei Radix et Rhizoma and Aconiti Lateralis Radix Praeparata was the basic herb pair applied in many Chinese traditional prescription. Rhubarb anthraquinones were the main bioactive materials of Rhei Radix et Rhizoma. To elucidate the compatibility of Rhei Radix et Rhizoma and Aconiti Lateralis Radix Praeparata, the pharmacokinetics of rhubarb anthraquinones as the main marker constituents were investigated. In the present study, pharmacokinetic differences of rhubarb anthraquinones were detected after oral administration of extract of Rheum palmatum L. and compatibility with Aconitum carmichaelii Debx. After oral administration, no difference of peak time can be found for anthraquinones between rhubarb group and compatibility group. But Cmax and area under the curve of aloe-emodin, emodin and chrysophanol in compatibility group were significantly higher than that in rhubarb group. Although the Cmax of rhein in compatibility group was much lower than that in rhubarb group, the area under the curve value was similar in two groups. The clearance and t1/2 of rhubarb anthraquinone were also changed after compatibility. The change of pharmacokinetics characteristics of rhubarb anthraquinone after compatibility may be caused by the drug-drug interaction medicated by chemical reaction and cytochromes P450.

The synergism mechanism of Rhubarb Anthraquinones on constipation elucidated by comparative pharmacokinetics of Rhubarb extract between normal and diseased rats.

In the study, it was hypothesized that Rhubarb Anthraquinones synergistically enhanced the purgative effect on constipation rat from the direct and indirect pathway at the same time. A validated HPLC method was successfully applied to elucidate the synergism mechanism from pharmacokinetics aspect after oral administration of Rhubarb extract with a dose of 0.25 g to normal and constipation rats. Comparison of the pharmacokinetic data of normal and constipation rats showed that there were significant differences (p < 0.05) in the main pharmacokinetic parameters. The C max and AUC of emodin in constipation rats were about ten times that of normal rats, while the t 1/2 was remarkably decreased (p < 0.05). However, a significant decrease (p < 0.05) in AUC value for aloe-emodin and rhein was observed in model group compared with normal group. The results may be attributed to the direct action of aloe-emodin and rhein on intestinal cell membranes and the indirect action of emodin on bowel movement through the adjustment by nervous system.

Development and validation of a UHPLC-qTOF-MS method for quantification of fuziline in rat plasma and its application in a pharmacokinetic study.

A specific and sensitive UHPLC-qTOF-MS method was developed and validated for quantification of fuziline in rat plasma after oral administration of three dosages. The analyte was separated on an Acquity UPLC BEH C18 column with a total running time of 3 min using a mobile phase of 0.1% formic acid aqueous solution and methanol (80:20, v/v) at a flow-rate of 0.25 mL/min. The calibration curves for fuziline showed good linearity in the concentrations ranging from 1 to 200 ng/mL with correlation coefficients >0.997. The precision, accuracy, recovery and stability were deemed acceptable. The method was applied to a pharmacokinetics study of fuziline in rats. The mean half-life was 5.93, 6.13 and 5.12 h for 1, 2 and 4 mg/kg oral administration of fuziline, respectively. The peak concentration and area under the concentration-time curve increased linearly with the doses. The sum of these results indicated that, in the range of the doses examined, the pharmacokinetics of fuziline in rat was based on first-order kinetics.

Assessment and modulation of forsythiaside absorption with MDCKII cells and validation with in situ intestinal experiment.

Forsythiaside was characterized by low intestinal absorption by in situ rat experiment and Caco-2 cells. The mechanisms behind this low absorption had not yet been elucidated. The purpose of this study was to investigate the role of efflux transporters in the intestinal absorption of forsythiaside as a potential mechanism for its low small-intestinal absorption following oral administration. Polarized MDCKII cell lines stably transfected with human or murine complementary DNA encoding for various efflux transporters (P-gp/MDR1, MRP2 and Bcrp1) were used to study transepithelial transport of forsythiaside and compare results with the MDCKII-Wild type cells. The transportation inhibitors GF120918, MK571 and Ko143 were used to investigate the transport mechanism. The active transport of forsythiaside was found in MDCKII-WT cells. The MDCKII-MRP2 and MDCKII-Bcrp1 cells significantly increased forsythiaside efflux ratio compared with the parental cells due to the apically directed transport by MRP2 and Bcrp1, respectively. The efflux ratios in MRP2 and Bcrp1 transfected cell lines were greatly decreased in the presence of MK-571 and Ko143, respectively, which indicated that forsythiaside efflux by MRP2 and Bcrp1 were significantly inhibited by their selective inhibitors. MDCKII-MDR1 cells did not exhibit a significant reduction in the forsythiaside efflux compared with the parental cells, indicating that it was not a good substrate for MDR1. And the results were then validated by the in situ experiment. This study presents direct evidence that forsythiaside is effluxed by both MRP2 and Bcrp1, which may contribute to its poor oral bioavailability.

Pharmacokinetics of phillyrin and forsythiaside following iv administration to Beagle dog.

The objective of the present study was to firstly investigate the in vivo pharmacokinetics of phillyrin and forsythiaside in beagle dog. On I.V. administration, a rapid distribution was observed and followed by a slower elimination for phillyrin and forsythiaside. The mean t(1/2Z) was 49.99, 34.87 and 43.81 min for 0.19, 0.70 and 1.43 mg/kg of phillyrin, and 60.90, 64.30, 57.99 min for 0.62, 1.39 and 5.52 mg/kg of forsythiaside respectively. And the AUC(o-t) increased linearly from 36.51 to 160.22 microg x min/ml of phillyrin and from 50.63 to 681.08 microg x min/ml after the three dosage administrated. In the range of the dose examined, the pharmacokinetics of phillyrin and forsythiaside in beagle dog was based on first order kinetics. Although both drugs were widely distributed to various tissues in the dog, no concerns about extensive binding to tissues that may be consumed by the public should a dog be exposed to phillyrin and forsythiaside according to the rapid elimination.