ß-eudesmol but not atractylodin exerts an inhibitory effect on CFTR-mediated chloride transport in human intestinal epithelial cells.

Oriental herbal medicine with the two bioactive constituents, ß-eudesmol (BE) and atractylodin (AT), has been used as a remedy for gastrointestinal disorders. There was no scientific evidence reporting their antidiarrheal effect and underpinning mechanisms. Therefore, we aimed to investigate the anti-secretory activity of these two compounds in vitro. The inhibitory effect of BE and AT on cAMP-induced Cl- secretion was evaluated by Ussing chamber in human intestinal epithelial (T84) cells. Short-circuit current (ISC) and apical Cl- current (ICl-) were measured after adding indirect and direct cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel activator. MTT assay was used to determine cellular cytotoxicity. Protein-ligand interaction was investigated by in silico molecular docking analysis. BE, but not AT concentration-dependently (IC50 of ~1.05 µM) reduced cAMP-mediated, CFTRinh-172 inhibitable Cl- secretion as determined by transepithelial ISC across a monolayer of T84 cells. Potency of CFTR-mediated ICl- inhibition by BE did not change with the use of different CFTR activators suggesting a direct blockage of the channel active site(s). Pretreatment with BE completely prevented cAMP-induced ICl-. Furthermore, BE at concentrations up to 200 µM (24 h) had no effect on T84 cell viability. In silico studies indicated that BE could best dock onto dephosphorylated structure of CFTR at ATP-binding pockets in nucleotide-binding domain (NBD) 2 region. These findings provide the first evidence for the anti-secretory effect of BE involving inhibition of CFTR function. BE represents a promising candidate for the therapeutic or prophylactic intervention of diarrhea resulted from intestinal hypersecretion of Cl.

A randomized placebo-controlled phase I clinical trial to evaluate the immunomodulatory activities of Atractylodes lancea (Thunb) DC. in healthy Thai subjects.

BACKGROUND: Atractylodes lancea (Thunb) DC. (AL) and bioactive compounds ß-eudesmol and atractylodin have been demonstrated in the in vitro and in vivo studies for their potential clinical use in cholangiocarcinoma. The study was a randomized, double-blinded, placebo-controlled phase I clinical trial to evaluate the immunomodulatory effect of AL in human subjects. METHODS: The modulatory effects of AL and ß-eudesmol and atractylodin on TNFα and IL6 expression in PBMCs were measured using real-time PCR. Blood samples were collected from forty-eight healthy subjects following oral administration of a single or multiple dosing of capsule formulation of the standardized AL extract or placebo. Serum cytokine profiles, lymphocyte subpopulations (B lymphocytes, CD8+ cytotoxic T lymphocytes, CD4+ T-helper lymphocytes, and NK cells), and cytotoxic activity of PBMCs against the cholangiocarcinoma cell line CL-6 were evaluated using cytometric bead array (CBA) with flow cytometry analysis. RESULTS: AL extract at almost all concentrations significantly inhibited both TNFα and IL6 expression in Con A-mediated inflammation in PBMCs. ß-Eudesmol at all concentrations significantly inhibited only IL6 expression. Atractylodin at the lowest concentration significantly inhibited the expression of both cytokines, while the highest concentration significantly inhibited only IL6 expression. The administration of AL at a single oral dose of 1000 mg appeared to decrease IFNγ and IL10 and increase B cell, while significantly increase NK and CD4+ and CD8+ cells. A trend of increasing (compared with placebo) in the cytotoxic activity of PBMCs at 24 h of dosing was observed. AL at multiple dosing of 1000 mg for 21 days tended to decrease the production of all cytokines, while significantly inhibited IL17A production at 24 h of dosing. In addition, a significant increase in CD4+ and CD8+ cells was observed. A trend of increase in the cytotoxic activity of PBMCs was observed at 24 h but terminated at 48 h of dosing. CONCLUSIONS: The results confirm the immunomodulatory activity of AL in humans. This activity, in complementary with the direct action of AL on inducing cholangiocarcinoma cell apoptosis, suggests its potential role for CCA control. TRIAL REGISTRATION: Retrospectively registered on 17 October 2020 [Thai Clinical Trials Registry (TCTR: www.clinical trials.in.th ) Number TCTR20201020001 #].

Intestinal Absorption of Isoalantolactone and Alantolactone, Two Sesquiterpene Lactones from Radix Inulae, Using Caco-2 Cells.

BACKGROUND: Isoalantolactone and alantolactone are the main sesquiterpene lactones in Radix Inulae (dried root of Inula helenium L. or I. racemosa Hook. F.), which is a frequently utilized herbal medicine. They also occur in several plants and have various pharmacologic effects. However, they have been found to have poor oral bioavailability in rats. OBJECTIVES: To understand the intestinal absorptive characteristics of isoalantolactone and alantolactone as well specific influx and efflux transporters in their absorption. METHODS: Bidirectional permeabilities of isoalantolactone and alantolactone were investigated across Caco-2 cell monolayers. Transport assays were performed using different concentrations of two lactones and specific inhibitors of ATP-binding cassette transporters and influx transporters. RESULTS: The absorption permeability of isoalantolactone and alantolactone was high at the tested concentrations (5, 20 and 80 µmol/l), and the major permeation mechanism of both lactones was found to be passive diffusion with active efflux mediated by multidrug resistance-associated proteins (MRPs) and breast cancer resistance protein (BCRP). CONCLUSION: Our results demonstrated that the absorption permeability of isoalantolactone and alantolactone was good in the Caco-2 cell model. The isoalantolactone and alantolactone absorption elucidated in this study provides useful information for further pharmacokinetics studies. Since low intestinal absorption can now be ruled out as a cause, further studies are needed to explain the low oral bioavailability of the two sesquiterpene lactones.

High body clearance and low oral bioavailability of alantolactone, isolated from Inula helenium, in rats: extensive hepatic metabolism and low stability in gastrointestinal fluids.

Alantolactone (ALA) is a major bioactive sesquiterpene lactone present in the roots of Inula helenium L. (Asteraceae) which has been used widely in traditional medicine against various diseases such as asthma, cancer and tuberculosis. The pharmacologic activities of alantolactone have been well characterized, yet information on the physicochemical and pharmacokinetic properties of alantolactone and their mechanistic elucidation are still limited. Thus, this study aims to investigate the oral absorption and disposition of alantolactone and their relevant mechanisms. Log P values of alantolactone ranged from 1.52 to 1.84, and alantolactone was unstable in biological samples such as plasma, urine, bile, rat liver microsomes (RLM) and simulated gastrointestinal fluids. The metabolic rate of alantolactone was markedly higher in rat liver homogenates than in the other tissue homogenates. A saturable and concentration-dependent metabolic rate profile of alantolactone was observed in RLM, and rat cytochrome P450 (CYP) 1 A, 2C, 2D and 3 A subfamilies were significantly involved in its hepatic metabolism. Based on the well-stirred model, the hepatic extraction ratio (HER) was estimated to be 0.890-0.933, classifying alantolactone as a drug with high HER. Moreover, high total body clearance (111 ± 41 ml/min/kg) and low oral bioavailability (0.323%) of alantolactone were observed in rats. Taken together, the present study demonstrates that the extensive hepatic metabolism, at least partially mediated by CYP, is primarily responsible for the high total body clearance of alantolactone, and that the low oral bioavailability of alantolactone could be attributed to its low stability in gastrointestinal fluids and a hepatic first-pass effect in rats. Copyright © 2016 John Wiley & Sons, Ltd.

Alantolactone Induces Apoptosis and Cell Cycle Arrest on Lung Squamous Cancer SK-MES-1 Cells.

Alantolactone, a sesquiterpene lactone compound, has variety of pharmacological properties, including anti-inflammatory and antineoplastic effects. In our study, alantolactone inhibited cancer cell proliferation. To explore the mechanisms underlying its antitumor action, we further examined apoptotic cells and cell cycle distribution using flow cytometry analysis. Alantolactone triggered apoptosis and induced cell cycle G1/G0 phase arrest. Furthermore, the expressions of caspases-8, -9, -3, PARP, and Bax were significantly upregulated, while antiapoptotic factor Bcl-2 expression was inhibited. In addition, the expressions of cyclin-dependent kinase 4 (CDK4), CDK6, cyclin D3, and cyclin D1 were downregulated by alantolactone. Therefore, our findings indicated that alantolactone has an antiproliferative role on lung squamous cancer cells, and it may be a promising chemotherapeutic agent for squamous lung cancer SK-MES-1 cells.

Japonicone A suppresses growth of Burkitt lymphoma cells through its effect on NF-κB.

PURPOSE: NF-κB, a transcriptional regulator of diverse genes involved in cell survival, proliferation, adhesion, and apoptosis, has been implicated in various malignancies. We discovered a potent natural NF-κB inhibitor, Japonicone A, from the traditional herb Inula japonica Thunb, evaluated its preclinical pharmacology and therapeutic activity, and investigated the underlying mechanisms of action for its antitumor activity. EXPERIMENTAL DESIGN: Various types of cancer and normal cells were exposed to Japonicone A for cytotoxicity screening, followed by determination of cell apoptosis and cell-cycle arrest. Western blotting, immunostaining, and gene reporter assay were used to analyze NF-κB activity. Two xenograft models were used for therapeutic efficacy evaluation. RESULTS: Japonicone A killed cancer cells but had low cytotoxicity to normal cells. Burkitt lymphoma cells were particularly sensitive. Japonicone A inhibited the growth and proliferation of Raji, BJAB, and NAMALWA lymphoma cells and resulted in G2-M phase arrest and apoptosis. Furthermore, exposure of cells to Japonicone A caused inactivation of the TNF-α-TAK1-IKK-NF-κB axis and inhibition of TNF-α-stimulated NF-κB activity and nuclear translocation, followed by downregulation of NF-κB target genes involved in cell apoptosis (Bcl-2, Bcl-xL, XIAP, TRAF2) and in the cell cycle and growth (cyclin D, c-Myc). Moreover, Japonicone A inhibited local growth and dissemination of cancer cells to multiple organs in vivo. CONCLUSION: Japonicone A exerts significant anticancer effects on Burkitt lymphoma cells in vitro and in vivo through targeting of the NF-κB signaling cascade. These results highlight the potential of Japonicone A as a chemotherapeutic agent and warrant its development as a therapy for lymphomas.

In vitro and in vivo antitumor effects of the essential oil from the leaves of Guatteria friesiana.

Guatteria friesiana (W. A. Rodrigues) Erkens & Maas (synonym Guatteriopsis friesiana W. A. Rodrigues), popularly known as "envireira", is a medicinal plant found in the Brazilian and Colombian Amazon basin that is used in traditional medicine for various purposes. Recent studies on this species have demonstrated antimicrobial activity. In this study, the antitumor activity of the essential oil from the leaves of G. friesiana (EOGF) and its main components ( α-, ß-, and γ-eudesmol) were determined using experimental models. In the in vitro study, EOGF and its components α-, ß-, and γ-eudesmol displayed cytotoxicity against tumor cell lines, showing IC50 values in the range of 1.7 to 9.4 µg/mL in the HCT-8 and HL-60 cell lines for EOGF, 5.7 to 19.4 µg/mL in the HL-60 and MDA-MB-435 cell lines for α-eudesmol, 24.1 to > 25 µg/mL in the SF-295 and MDA-MB-435 cell lines for ß-eudesmol, and 7.1 to 20.6 µg/mL in the SF-295 and MDA-MB-435 cell lines for γ-eudesmol, respectively. In the in vivo study, the antitumor effect of EOGF was evaluated in mice inoculated with sarcoma 180 tumor cells. Tumor growth inhibition rates were 43.4-54.2 % and 6.6-42.8 % for the EOGF treatment by intraperitoneal (50 and 100 mg/kg/day) and oral (100 and 200 mg/kg/day) administration, respectively. The treatment with EOGF did not significantly affect body mass, macroscopy of the organs, or blood leukocyte counts. Based on these results, we can conclude that EOGF possesses significant antitumor activity and has only low systemic toxicity. These effects could be assigned to its components α-, ß-, and γ-eudesmol.

Eudesmanolides from Taraxacum mongolicum and their inhibitory effects on the production of nitric oxide.

A new eudesmanolide, 1ß,3ß-dihydroxy-eudesman-11(13)-en-6α,12-olide (1) was isolated and identified from Taraxacum mongolicum, together with two known compounds, 1ß,3ß-dihydroxyeudesman-6α,12-olide (2) and loliolide (3). The structure of 1 was established by analysis of its physical and spectroscopic data. 1 was found to have an inhibitory activity on nitric oxide production with an IC(50) of 38.9 µM in activated RAW 264.7 cells.