New fatty acid esters originate during storage by the interaction of components in prasaplai, a Thai traditional medicine

Predicting Cyclooxygenase Inhibition by Three-Dimensional Pharmacophoric Profiling. Part I: Model Generation, Validation and Applicability in Ethnopharmacology

3D pharmacophore modeling has evolved as an established and state-of-the-art method for performing in-silico predictions of biological activity. Using one single model is limited to single binding modes, while the combination of several models bears a broader application scope. We demonstrate the generation of a complete and predictive 3D model set for cyclooxygenase 1 and 2 inhibitors, along with a selection and validation protocol optimized for parallel virtual screening. This model set was applied to explain the cyclooxygenase activity of an ethnopharmacologically known mixture of natural products, the Thai traditional medicine "Prasaplai". Results show that rationalizing natural product activity by modern in-silico approaches is promising and can be tremendously useful in the identification of the mechanisms of action for known biological effects of complex herbal remedies.

The potential of metabolic fingerprinting as a tool for the modernisation of TCM preparations

A vast majority Chinese herbal medicines (CHM) are traditionally administered as individually prepared water decoctions (tang) which are rather complicated in practice and their dry extracts show technological problems that hamper straight production of more convenient application forms. Modernised extraction procedures may overcome these difficulties but there is lack of clinical evidence supporting their therapeutic equivalence to traditional decoctions and their quality can often not solely be attributed to the single marker compounds that are usually used for chemical extract optimisation. As demonstrated by the example of the rather simple traditional TCM formula Danggui Buxue Tang, both the chemical composition and the biological activity of extracts resulting from traditional water decoction are influenced by details of the extraction procedure and especially involve pharmacokinetic synergism based on co-extraction. Hence, a more detailed knowledge about the traditional extracts' chemical profiles and their impact on biological activity is desirable in order to allow the development of modernised extracts that factually contain the whole range of compounds relevant for the efficacy of the traditional application. We propose that these compounds can be identified by metabolomics based on comprehensive fingerprint analysis of different extracts with known biological activity. TCM offers a huge variety of traditional products of the same botanical origin but with distinct therapeutic properties, like differentially processed drugs and special daodi qualities. Through this variety, TCM gives an ideal field for the application of metabolomic techniques aiming at the identification of active constituents.

Predicting cyclooxygenase inhibition by three-dimensional pharmacophoric profiling. Part II: Identification of enzyme inhibitors from Prasaplai, a Thai traditional medicine

Prasaplai is a medicinal plant mixture that is used in Thailand to treat primary dysmenorrhea, which is characterized by painful uterine contractility caused by a significant increase of prostaglandin release. Cyclooxygenase (COX) represents a key enzyme in the formation of prostaglandins. Former studies revealed that extracts of Prasaplai inhibit COX-1 and COX-2. In this study, a comprehensive literature survey for known constituents of Prasaplai was performed. A multiconformational 3D database was created comprising 683 molecules. Virtual parallel screening using six validated pharmacophore models for COX inhibitors was performed resulting in a hit list of 166 compounds. 46 Prasaplai components with already determined COX activity were used for the external validation of this set of COX pharmacophore models. 57% of these components were classified correctly by the pharmacophore models. These findings confirm that the virtual approach provides a helpful tool (i) to unravel which molecular compounds might be responsible for the COX-inhibitory activity of Prasaplai and (ii) for the fast identification of novel COX inhibitors.

Quantitative analysis and toxicity determination of artifacts originated in a Thai traditional medicine Prasaplai

Prasaplai is a Thai traditional medicine for relieving dysmenorrhea and adjusting the menstrual cycle. Three fatty acid esters, (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl linoleate (1), (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl oleate (2) and (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl palmitate (3) are formed during storage from the reaction of chemical components in two herbs, i.e., fatty acids in Nigella sativa (L.) (Ranunculaceae) and (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-ol (compound D) in Zingiber cassumunar (Roxb.) (Zingiberaceae). The formations of these artifacts were monitored for 1 year and their amounts were analyzed by HPLC at certain periods of time. The results showed that artifact formation was saturated after 73 days of storage. The amount of each artifact in the saturation period ranged from 3.93 +/- 0.06 to 4.30 +/- 0.18% w/w for compound 1, 1.69 +/- 0.08 to 1.9 +/- 0.13% w/w for compound 2 and 0.09 +/- 0.003 to 0.1 +/- 0.005% w/w for compound 3. Cytotoxicity of the artifacts was evaluated using NCI-H187, KB, and BC cancer cell lines and found that the IC(50) of all artifacts in all tests were higher than 20 microg/mL. For acute toxicity in mice, the LD(50) of each artifact was more than 300 mg/kg.

Cellular transport of anti-inflammatory pro-drugs originated from a herbal formulation of Zingiber cassumunar and Nigella sativa

Background

The rhizome of Zingiber cassumunar and the seed of Nigella sativa are two ingredients in Thai traditional medicine to relieve dysmenorrhea and adjust the menstrual cycle. Mixture of these two herbs produces three esters, namely (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl linoleate (1), (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl oleate (2) and (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl palmitate (3). The aim of this study is to examine in vitro absorption of these esters and evaluate their transport across the membrane.

Methods

In vitro transport of these three esters was observed in Caco-2 cell monolayers. The ester compounds 1, 2 and 3 at a concentration of 10 μM were hydrolyzed by porcine liver esterase.

Results

All esters transported across the Caco-2 cell without enzymatic hydrolysis. The apparent permeability coefficients P_app of compound 1 at 53 μM and 106 μM were 13.94 (0.60) × 10^-6 and 14.33 (0.17) × 10^-6cm/s respectively, while those of compound 2 were 9.45 (0.29) × 10^-6 and 10.08 (0.32) × 10^-6cm/s, respectively. P_app values of compound 3 were 7.48 (0.31) × 10^-6cm/s at 53 μM and 8.60 (0.55) × 10^-6cm/s at 106 μM. P_app values of the parent compound (compound D), i.e. (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-ol were 8.53 (0.83) × 10^-6cm/s at 53 μM and 16.38 (0.61) × 10^-6cm/s at 106 μM. The ester hydrolysis of compounds 1, 2 and 3 by porcine liver esterase was monitored by HPLC and the hydrolysis reactions were completed within 10 minutes.

Conclusion

Using the Caco-2 cell monolayer model, the present study finds that compounds (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl linoleate (1), (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl oleate (2) and (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl palmitate (3) originated from Prasaplai preparation (a Thai herbal formula) may be transported through a facilitated mechanism and serve as pro-drugs to increase the compound D level in the blood.

Biological evaluations of fatty acid esters originated during storage of Prasaplai, a Thai traditional medicine

Three fatty acid esters, (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl linoleate (1), (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl oleate (2), and (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl palmitate (3), originated during storage by the interaction of components in Prasaplai, were synthesized. These three artificial esters were subjected to four biological evaluations. All three compounds were active against Mycobacterium tuberculosis H(37)Ra for which compounds 1 and 3 had inhibitory concentration at 200 microg mL(-1) while compound 2 inhibited at 100 microg mL(-1). When all these compounds were subjected to anti-HSV-1 test, compound 2 showed positive activity at 42.6 microg mL(-1) without any cytotoxic activity against human vero cell line while compound 3 had the cytotoxicity to vero cell at IC(50) 38 microg mL(-1). Compound 1 was inactive for this test.