The intestinal permeability of neolignans from the seeds of Myristica fragrans in the Caco-2 cell monolayer model

Anti-Proliferative Acyl Phenols and Arylnonanoids from the Fruit Rind of Myristica malabarica Lam

Phytochemical investigation of the methanol extract of the fruit rind of Myristica malabarica led to the isolation of eight known compounds that were identified as malabaricones A-D, promalabaricones B and C, 1-(2,6-dihydroxyphenyl)tetradecan-1-one, and ericanone by comparison with literature spectroscopic data. The structures of malabaricones A-D, promalabaricone B, and 1-(2,6-dihydroxyphenyl)tetradecan-1-one were confirmed by X-ray crystallography. In vitro assay of the isolated phenols indicated that they exhibited moderate anti-proliferative activity against the A2780 human ovarian cancer cell. Compounds (1, 3, 5, 6 and 7) had the most potent activities, whereas the anti-proliferative activities of compounds 2 and 4 were less potent.

Determination of myrislignan levels in BALB/c mouse plasma by LC-MS/MS and a comparison of its pharmacokinetics after oral and intraperitoneal administration

Background

Myrislignan is a natural product from Myristica sp. with diverse pharmacological activities. Recently, the anti-Toxoplasma gondii (T. gondii) activity of myrislignan has been proposed, and in vivo studies of its pharmacokinetics in BALB/c mice are necessary to further evaluate the clinical effects of myrislignan.

Results

In this study, a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to quantify myrislignan levels in mouse plasma using dehydrodiisoeugenol as an internal standard (IS) in positive ion mode. Chromatographic separation of the analytes was achieved using an ACE Ultracore Super C18 analytical column (2.5 μm, 2.1 × 50 mm) at 30 °C. A gradient mobile phase consisting of water (0.1 % formic acid) and acetonitrile (0.1 % formic acid) was delivered at a flow rate of 0.4 mL/min. Myrislignan and the IS eluted at 1.42 and 1.71 min, respectively. A good excellent linear response across the concentration range of 1-1000 ng/mL was achieved (r² = 0.9973). The lower limit of quantification (LLOQ) was 1 ng/mL, and the inter- and intra-day accuracy and precision of the method showed relative standard deviations (RSDs) less than 10 %. The method was applied to examine the pharmacokinetics of myrislignan in mouse plasma following a single oral administration of 200 mg/kg or intraperitoneal administration of 50 mg/kg myrislignan, and the bioavailability (F) of orally administered myrislignan was only 1.97 % of the bioavailability of intraperitoneally administered myrislignan.

Conclusions

A rapid and sensitive LC-MS/MS method has been was developed, validated and successfully used to determine myrislignan levels in mice after oral or intraperitoneal administration. This study is the first to report the pharmacokinetic parameters of myrislignan in mice and to compare its pharmacokinetics after oral and intraperitoneal administration, which will be useful for further research on the administration of myrislignan in animals and humans.

Effect of sulfur-fumigation process on ginseng: Metabolism and absorption evidences

ETHNOPHARMACOLOGICAL RELEVANCE

Sulfur-fumigation has been developed to prevent insects and molds during post-harvest handling of Panax ginseng C.A. Mey (ginseng) in the near decades. Our previous study indicated sulfur-fumigation could transform ginsenosides, the active components of ginseng, into sulfur-containing derivatives (SFCDs), the artifacts with unknown toxicity. However, whether the biotransformation could be occurred and absorption characteristics between ginsenosides and SFCDs are still needed to further investigate.

AIM OF THE STUDY

To evaluate the effect of sulfur-fumigation process on ginseng through comparing the metabolic profile and absorption characteristics between ginsenoside Rg1, Re and their SFCDs.

MATERIALS AND METHODS

Intestinal microflora and liver S9 fraction were utilized to compare the metabolic profile, and single-pass intestinal perfusion and Caco-2 cell models were applied to compare the absorption characteristics, between Rg1, Re and their SFCDs.

RESULTS

Rg1 and Re were metabolized to 7 none sulfur-containing metabolites, while their SFCDs were metabolized to 18 sulfur-containing metabolites. The intestinal absorption and transport of Rg1 and Re were much greater than their SFCDs. Besides, the uptakes of Rg1 and Re were transport-dependent, but their SFCDs were non-transport-dependent.

CONCLUSION

Ginsenosides and their SFCDs could not be bio-transformed with each other and their absorption characteristics were quite different, which suggested that sulfur-fumigation is not a feasible post-harvest process of ginseng.

Metabolic profiling of myrislignan by UPLC-ESI-QTOFMS-based metabolomics

The metabolic map of myrislignan was determined by UPLC-ESI-QTOFMS-based metabolomics in vivo and in vitro.

Chemical diversity and pharmacological significance of the secondary metabolites of nutmeg (Myristica fragrans Houtt.)

Nutmeg is a valued kitchen spice that has been used for centuries all over the world. In addition to its use in flavoring foods and beverages, nutmeg has been used in traditional remedies for stomach and kidney disorders. The antioxidant, antimicrobial and central nervous system effects of nutmeg have also been reported in literature. Nutmeg is a rich source of fixed and essential oil, triterpenes, and various types of phenolic compounds. Many of the secondary metabolites of nutmeg exhibit biological activities that may support its use in traditional medicine. This article provides an overview of the chemistry of secondary metabolites isolated from nutmeg kernel and mace including common methods for analysis of extracts and pure compounds as well as recent approaches towards total synthesis of some of the major constituents. A summary of the most significant pharmacological investigations of potential drug leads isolated from nutmeg and reported in the last decade is also included.

The action and mechanism of myrislignan on A549 cells in vitro and in vivo

Myrislignan is a natural compound with little pharmacological study. In our investigation, we investigated the effect of myrislignan in the induction of apoptosis in A549 cells in vitro and in vivo. Myrislignan inhibited the proliferation of A549 cells in a dose- and time-dependent manner assayed by MTT. In addition, Hoechst flow cytometry showed that myrislignan significantly induced apoptosis and cell cycle arrest in A549 cells. The apoptosis and anti-cell proliferation was mediated by the activation of mitogen-activated protein kinase and the inhibition of epidermal growth factor receptor signal pathway, change of mitochondrial membrane potential, the releasing of c-Myc, the downregulation of the level of the anti-apoptotic protein Bcl-2, and the upregulation of the level of the pro-apoptotic protein Bax. In conclusion, those results reveal a potential mechanism for the anti-cancer effect of myrislignan on human lung cancer, while suggesting that myrislignan may be a promising compound for the treatment of lung cancer.

The octanol/water distribution coefficients of ardipusilloside-I and its metabolites, and their permeation characteristics across Caco-2 cell monolayer

Background

Ardipusilloside-I (ADS-I) is a triterpenoid saponin extracted from Chinese medicinal herb Ardisiapusill A. DC. Previous studies have demonstrated the potent anti-tumor activities of ADS-I both in vitro and in vivo, and its main metabolites (M1 and M2) from human intestinal bacteria. However, the physicochemical properties and intestinal permeation rate of ADS-I and its metabolites are not understood. In this study, the octanol/water distribution coefficients (logP) of ADS-I and metabolites were investigated using standard shake flask technique, and their permeability properties was investigated across Caco-2 cells monolayer.

Results

The logP of ADS-I, M1 and M2 was −0.01, 0.95 ± 0.04, 1.57 ± 0.11, respectively. The P_app values of ADS-I, M1 and M2 (in 10 μmol/L) across Caco-2 cell monolayers from the apical (AP) to basolateral (BL) direction were 1.88 ± 0.21 × 10⁻⁶ cm·s⁻¹, 4.30 ± 0.43 × 10⁻⁶ cm·s⁻¹, 4.74 ± 0.47 × 10⁻⁶ cm·s⁻¹, respectively.

Conclusion

Our data indicated that ADS-I has the poorer intestinal absorption than its metabolites (M1 and M2) in these experimental systems, suggesting that the metabolites of ADS-I may be the predominant products absorbed by the intestine when ADS-I is administered orally.

The Blood-Brain Barrier Permeability of Lignans and Malabaricones from the Seeds of Myristica fragrans in the MDCK-pHaMDR Cell Monolayer Model

The blood-brain barrier (BBB) permeability of twelve lignans and three phenolic malabaricones from the seeds of Myristica fragrans (nutmeg) were studied with the MDCK-pHaMDR cell monolayer model. The samples were measured by high-performance liquid chromatography and the apparent permeability coefficients (P_app) were calculated. Among the fifteen test compounds, benzonfuran-type, dibenzylbutane-type and arylnaphthalene-type lignans showed poor to moderate permeabilities with P_app values at 10⁻⁸–10⁻⁶ cm/s; those of 8-O-4′-neolignan and tetrahydrofuran-lignan were at 10⁻⁶–10⁻⁵ cm/s, meaning that their permeabilities are moderate to high; the permeabilities of malabaricones were poor as their P_app values were at 10⁻⁸–10⁻⁷ cm/s. To 5-methoxy-dehydrodiisoeugenol (2), erythro-2-(4-allyl-2,6-dimethoxyphenoxy)-1-(3,4-dimethoxyphenyl)-propan-1-ol acetate (6), verrucosin (8), and nectandrin B (9), an efflux way was involved and the main transporter for 6, 8 and 9 was demonstrated to be P-glycoprotein. The time and concentration dependency experiments indicated the main transport mechanism for neolignans dehydrodiisoeugenol (1), myrislignan (7) and 8 was passive diffusion. This study summarized the relationship between the BBB permeability and structure parameters of the test compounds, which could be used to preliminarily predict the transport of a compound through BBB. The results provide a significant molecular basis for better understanding the potential central nervous system effects of nutmeg.

Study of the Biotransformation of Tongmai Formula by Human Intestinal Flora and Its Intestinal Permeability across the Caco-2 Cell Monolayer

Tongmai formula (TMF) is a well-known Chinese medicinal preparation that contains isoflavones as its major bioactive constituents. As traditional Chinese medicines (TCMs) are usually used by oral administration, their fate inside the intestinal lumen, including their biotransformation by human intestinal flora (HIF) and intestinal absorption deserves study. In this work TMF extract was incubated with human intestinal bacteria under anaerobic conditions and the changes in the twelve main constituents of TMF were then investigated. Their intestinal permeabilities, i.e., the transport capability across the intestinal brush border were investigated with a human colon carcinoma cell line (Caco-2) cell monolayer model to predict the absorption mechanism. Meanwhile, rapid HPLC-DAD methods were established for the assay. According to the biotransformation curves of the twelve constituents and the permeability coefficients, the intestinal absorption capacity of the typical compounds was elevated from the levels of 10(-7) cm/s to 10(-5) cm/s from those of the original compounds in TMF. Among them the main isoflavone glycosides puerarin (4), mirificin (6) and daidzin (7) were transformed into the same aglycone, daidzein (10). Therefore it was predicted that the aglycone compounds might be the real active ingredients in TMF. The models used can represent a novel path for the TCM studies.

Intestinal Absorption of Ergostane and Lanostane Triterpenoids from Antrodia cinnamomea Using Caco-2 Cell Monolayer Model

Antrodia cinnamomea is a precious medicinal mushroom. It exhibits promising therapeutic effects on cancer, intoxication, hypertension, hepatitis, and inflammation. Its major bioactive constituents are ergostane and lanostane triterpenoids. In this study, we used intestinal Caco-2 cell monolayer model to reveal the intestinal absorption property of 14 representative triterpenoids from A. cinnamomea. The bidirectional transport through the monolayer at different time points was monitored by a fully validated LC/MS/MS method. In the case of pure compounds, ergostanes 5 (25R-antcin H), 6 (25S-antcin H) and 10 (25R-antcin B) could readily pass through the Caco-2 cell layer, whereas lanostanes 13 (dehydroeburicoic acid) and 14 (eburicoic acid) could hardly pass through. When the cells were treated with A. cinnamomea extract, antcins A, B, C, H and K (1-6 and 9-11) were absorbed via passive transcellular diffusion, and showed high P AB and P BA values (> 2.5 × 10(-5) cm/s). Meanwhile, the lanostanes dehydrosulphurenic acid (8), 15α-acetyldehydrosulphurenic acid (12), 13 and 14 exhibited poor permeability. Transport features of these compounds were consistent with their pharmacokinetic behaviors in rats. This study could also be helpful in predicting the intestinal absorption of A. cinnamomea in human.

Transport of Twelve Coumarins from Angelicae Pubescentis Radix across a MDCK-pHaMDR Cell Monolayer-An in Vitro Model for Blood-Brain Barrier Permeability

Angelicae Pubescentis Radix (APR), a widely used traditional Chinese medicine, is reported to have central nervous system activities. The purpose of this study was to characterize the blood-brain barrier permeability of twelve coumarins from APR including umbelliferone (1), osthol (2), scopoletin (3), peucedanol (4), ulopterol (5), angepubebisin (6), psoralen (7), xanthotoxin (8), bergapten (9), isoimperatorin (10), columbianadin (11), and columbianetin acetate (12) with an in vitro model using a MDCK-pHaMDR cell monolayer. The cell monolayer was validated to be suitable for the permeation experiments. The samples’ transports were analyzed by high performance liquid chromatography and their apparent permeability coefficients (P_app) were calculated. According to the P_app value, most coumarins could be characterized as well-absorbed compounds except for 4, 10 and 11 which were moderately absorbed ones, in concentration-dependent and time-dependent manners. The results of P-glycoprotein (P-gp) inhibitor (verapamil) experiments showed that the transport of coumarin 4 was affected by the transport protein P-gp. Sigmoid functions between permeability log(P_{app AP-BL}*MW^0.5) and log D (at pH 7.4) were established to analyze the structure-activity relationship of coumarins. The results provide useful information for discovering the substance basis for the central nervous system activities of APR, and predicting the permeability of other coumarins through BBB.

Evaluation of the intestinal transport of a phenylethanoid glycoside-rich extract from Cistanche deserticola across the Caco-2 cell monolayer model

Phenylethanoid glycosides (PhGs), a class of polyphenolic compounds, are considered one of major bioactive constituents of Cistanche deserticola Y.C. Ma (CD), whose extract is orally used in traditional Chinese medicine. Although previous pharmacological studies have reported that PhGs exert many activities, their intestinal transport profiles have not been clarified. In this study, we investigated the intestinal permeability of a PhG-rich extract (PRE) from CD as an integrated system in the Caco-2 cell monolayer model using a bioassay system. The results showed that PRE is primarily transported via poorly absorbed passive diffusion down a concentration gradient without efflux, which provides the pharmacokinetic basis for the clinical application of PhGs in CD. We also determined the intestinal permeability of three major PhGs [acteoside (AC), isoacteoside (IS) and echinacoside (EC)] by HLPC. Furthermore, we developed a novel HPLC-fluorescence detection method to accurately determine the flux amount of AC and IS. As expected, the transport characteristics of the three PhGs are consistent with those of PRE, indicating that the present bioassay system is appropriate and reliable for the evaluation of the transport characteristics of active ingredient groups (AIG) in PRE. Moreover, this system may also be suitable for other plant extracts given appropriate bioactivity.

New neolignans from the seeds of Myristica fragrans that inhibit nitric oxide production

Five new 8-O-4' type neolignans, named myrifralignan A-E (1-5), together with five known analogues (6-10), were isolated from the seeds of Myristica fragrans Houtt. Their chemical structures were determined using several spectroscopic methods. Compounds 3-10 exhibited potent inhibitory activity against the production of nitric oxide (NO) in the RAW264.7 cell line stimulated by lipopolysaccaride. Myrislignan (7) and machilin D (10) were the most potent inhibitors of NO production amongst these compounds. The IC50 values of myrislignan and machilin D were 21.2 and 18.5 μM. And, their inhibitory activity was more than L-N(6)-(1-iminoethyl)-lysine, a selective inhibitor of inducible nitric oxide synthase (IC50=27.1 μM). Furthermore, real-time PCR analysis revealed that these neolignans could significantly suppress the expression of inducible nitric oxide synthase mRNA. These results demonstrated that the 8-O-4' type neolignans are promising candidates as anti-inflammatory agents.

Analysis of anti-inflammatory dehydrodiisoeugenol and metabolites excreted in rat feces and urine using HPLC-UV

Dehydrodiisoeugenol (DDIE) is a lignan in the fruit of Myristica fragrans. It can be converted into several metabolites in in vitro and in vivo metabolism. In this study, the excretion of DDIE in urine and feces was investigated after intravenous (i.v.) and intragastric (i.g.) administration to rats. DDIE and its metabolites (M-1 and M-2) were measured using HPLC. The amount of DDIE and its metabolites excreted was higher in feces than in urine, suggesting that DDIE and its metabolites are eliminated primarily in the feces. Significant differences in the excretion levels of DDIE and its metabolites were seen between i.v. and i.g. administration. Greater amounts of DDIE and its metabolites were excreted following i.v. administration, suggesting that DDIE can exert a longer period of anti-inflammatory activity following i.g. administration. The accuracy, precision, recovery and stability of the analytical method in this study were satisfactory for the measurement of DDIE and its metabolites in rat urine and feces. Observations made in this study will contribute to understanding of the absorption, distribution, metabolism and excretion pathway of DDIE and will aid decision-making regarding the best mode of DDIE administration during treatment to maximize its anti-inflammatory effects.