Two new triterpenes from the rhizomes of Alisma orientalis

Natural soluble epoxide hydrolase inhibitors from Alisma orientale and their potential mechanism with soluble epoxide hydrolase

Inhibition of soluble epoxide hydrolase (sEH) is considered to be an effective treatment for inflammation-related diseases, and small molecules origin from natural products show promising activity against sEH. Two undescribed protostanes, 3β-hydroxy-25-anhydro-alisol F (1) and 3β-hydroxy-alisol G (2) were isolated from Alisma orientale and identified as new sEH inhibitors with IC₅₀ values of 10.06 and 30.45 μM, respectively. Potential lead compound 1 was determined as an uncompetitive inhibitor against sEH, which had a K_i value of 5.13 μM. In-depth molecular docking and molecular dynamics simulations revealed that amino acid residue Ser374 plays an important role in the inhibition of 1, which also provides an idea for the development of sEH inhibitors based on protostane-type triterpenoids.

Alisma genus: Phytochemical constituents, biosynthesis, and biological activities

The genus Alisma contains 11 species distributed worldwide, of which at least two species (A. orientale [Sam.] Juzep. and A. plantago-aquatica Linn.) have been used as common herbal medicines. Secondary metabolites obtained from the genus Alisma are considered to be the material basis for the various biological functions and medicinal applications. In this review, we mainly focused on the recent investigations of secondary metabolites from plants of the genus Alisma and their biological activities, with the highlighting on the diversity of the chemical structures, the biosynthesis of interesting secondary metabolites, the biological activities, and the relationships between structures and bioactivities.

The structural composition of components contributes to the superiority of the geoherb Alisma orientale for "diuresis and diffusing dampness"

The purpose of this study is to explore the intrinsic reasons for the superiority of the salt-made geoherb Alisma orientale via comparing the content of various components of the salt-made geoherb Alisma orientale. The effects of "diuresis and diffusing dampness" using salt-made Alisma orientale from seven different origins were investigated through pharmacodynamic experiments in vivo and in vitro. The results indicated that salt-made Alisma orientale from different origins had diuretic efficacy; this was demonstrated by the significant increase in the volume of rat urine, the concentration of Na+, K+, and Cl- in the urine, and the significant decrease in the levels of AQP-2 in rat renal medulla and HK-2 cells. It was also revealed that the diuretic effect of salt-made Alisma orientale from Fujian Province is stronger than those from other provinces. Moreover, the main components and their proportions in the salt-made Alisma orientale samples were further analyzed via principal component analysis. The results showed that alisol A 24-acetate, alisol B, and 23-acetyl alisol B are the main components of salt-made Alisma orientale, and the optimal structural ratio of alisol A 24-acetate, alisol B, and 23-acetyl alisol B was found to be 5.38 : 14.34 : 11.31 via optimizing the ratios of the three main components. It is worth noting that the optimal ratio of the three main components after optimization is the closest to the ratio of the three main components in salt-made Alisma orientale from Fujian Province. This paper reveals the "mystery" of the content ratio of the main active components and its effect on the efficacy, and showed that the proportional relationship between the content of multiple components is the key to their interactions. Therefore, this method of evaluating the quality of salt-made Alisma orientale is obviously reliable, and this study lays the foundations for quality evaluation of salt-made Alisma orientale and other herb slices.

Triterpenoids From Alisma Species: Phytochemistry, Structure Modification, and Bioactivities

Plants from Alisma species belong to the genus of Alisma Linn. in Alismataceae family. The tubers of A. orientale (Sam.) Juzep, also known as Ze Xie in Chinese and Takusha in Japanese, have been used in traditional medicine for a long history. Triterpenoids are the main secondary metabolites isolated from Alisma species, and reported with various bioactive properties, including anticancer, lipid-regulating, anti-inflammatory, antibacterial, antiviral and diuretic activities. In this brief review, we aimed to summarize the phytochemical and pharmacological characteristics of triterpenoids found in Alisma, and discuss their structure modification to enhance cytotoxicity as well.

Novel C-17 spirost protostane-type triterpenoids from Alisma plantago-aquatica with anti-inflammatory activity in Caco-2 cells

Twenty-one protostane-type triterpenoids with diverse structures, including nine new compounds (1-9), were isolated from the of Alisma plantago-aquatica Linn. Structurally, alisolides A‒F (1-6), composed of an oxole group coupled to a five-membered ring, represent unusual C-17 spirost protostane-type triterpenoids. Alisolide H (8) is a novel triterpenoid with an unreported endoperoxide bridge. Alisolide I (9) represents the first example of 23,24-acetal triterpenoid. Their structures were elucidated based on spectroscopic analysis, wherein the absolute configurations of 4‒6, 8 were further confirmed by the Mo2(OAc)4-induced ECD method. Furthermore, all isolates were evaluated for their inhibitory effects on LPS-induced NO production in Caco-2 cells, and all the compounds showed remarkable inhibitory activities, with IC50 values in the range of 0.76-38.20 μmol/L.

Chemistry and Pharmacology of GPBAR1 and FXR Selective Agonists, Dual Agonists, and Antagonists

In the recent years, bile acid receptors FXR and GPBAR1 have attracted the interest of scientific community and companies, as they proved promising targets for the treatment of several diseases, ranging from liver cholestatic disorders to metabolic syndrome, inflammatory states, nonalcoholic steatohepatitis (NASH), and diabetes.Consequently, the development of dual FXR/GPBAR1 agonists, as well as selective targeting of one of these receptors, is considered a hopeful possibility in the treatment of these disorders. Because endogenous bile acids and steroidal ligands, which cover the same chemical space of bile acids, often target both receptor families, speculation on nonsteroidal ligands represents a promising and innovative strategy to selectively target GPBAR1 or FXR.In this review, we summarize the most recent acquisition on natural, semisynthetic, and synthetic steroidal and nonsteroidal ligands, able to interact with FXR and GPBAR1.

Correlation analysis between the chemical contents and bioactivity for the quality control of Alismatis Rhizoma

In order to clarify regions of production and to discriminate processing methods, quantitative and qualitative analyses for saccharides and terpenes in 35 batches of Alismatis Rhizoma were performed. Methodologies included HPLC—PDA, HPLC—VWD and UHPLC—MSⁿ, combined with principal component analysis (PCA) and partial least squares regression techniques (PLSR). The inhibitory effects of triterpenes and Alismatis Rhizoma extracts on lipase activity were evaluated in vitro. PLSR analysis revealed significant positive correlations (R² = 0.5795) between the contents of triterpenes 10, 14, 15, 18 and 22 and the inhibitory effects of Alismatis Rhizoma. The present study establishes an effective method for simultaneous determination of multiple components, and identifies key bioactive triterpenes. These results can be used for systematic and novel analytical strategies for the quality control of Alismatis Rhizoma production.

Alisma orientale: Ethnopharmacology, Phytochemistry and Pharmacology of an Important Traditional Chinese Medicine

Alisma orientale (Sam.) Juzep. (Alismataceae) is a traditional and famous Chinese medicinal herb. Its rhizomes, which possess versatile bioactivities, are commonly used to treat oliguria, edema, gonorrhea with turbid urine, leukorrhea, diarrhea and dizziness. Approximately 120 compounds have been isolated from A. orientale. Terpenoids have been identified as A. orientale's characteristic constituents, which include protostane triterpenoids and guaiane sesquiterpenoids. The traditional medical uses of A. orientale in TCM have been evaluated in modern pharmacological studies, which have shown that A. orientale and its active constituents exhibit a wide range of bioactivities, such as diuretic, anti-urolithiatic, antinephritic, anti-atherosclerotic, immunomodulatory, and hepatoprotective activities. The medicinal potential of A. orientale makes it an ideal candidate for new drug development. Further studies are still required to identify its bioactive constituents, and elucidate the structure-activity relationship and detailed mechanisms of action. Additionally, the use of the other medicinal parts of A. orientale may reduce resource waste and afford novel secondary metabolites.

Structures and biological activities of the triterpenoids and sesquiterpenoids from Alisma orientale

Sixteen triterpenoids and nine sesquiterpenoids were isolated from the rhizome of Alisma orientale. Structures of 16-oxo-11-anhydroalisol A 24-acetate, 13β,17β-epoxy-24,25,26,27-tetranor-alisol A 23-oic acid, 1αH,5αH-guaia-6-ene-4β,10β-diol, and alisguaiaone were elucidated by comprehensive spectroscopic data analysis. The cytotoxic, antibacterial, antifungal, anti-inflammatory, and α-glucosidase inhibitory activities of isolated terpenoids were evaluated. Triterpenoids alisol A, alisol A 24-acetate, 25-O-ethylalisol A, 11-deoxyalisol A, alisol E 24-acetate, alisol G, alisol B 23-acetate and sesquiterpenoids 1αH,5αH-guaia-6-ene-4β,10β-diol, 10-hydroxy-7,10-epoxysalvialane exhibited cytotoxicities against the three tested human cancer cell lines with IC₅₀ values ranging from 11.5 ± 1.7 μM to 76.7 ± 1.4 μM. Triterpenoids alisol A, 25-O-ethylalisol A, 11-deoxyalisol A, alisol E 24-acetate, alisol G, and 25-anhydroalisol F showed antibacterial activities against the Gram-positive strains Bacillus subtilis and Staphylococcus aureus with MIC values of 12.5-100 μg/mL. Sesquiterpenoid 4β,10β-dihydroxy-1αH,5βH-guaia-6-ene exhibited antibacterial activity against B. subtilis with an MIC value of 50 μg/mL, and 10-hydroxy-7,10-epoxysalvialane exhibited activity against S. aureus with an MIC value of 100 μg/mL. Compounds 16-oxo-11-anhydroalisol A 24-acetate, alisol F, 25-anhydroalisol F, and alisguaiaone exhibited inhibitory effects on lipopolysaccharide-induced NO production in RAW 264.7 macrophage cells. None of the compounds showed obvious inhibitory activity against α-glucosidase.

Traditional uses, phytochemistry, pharmacology, toxicology and quality control of Alisma orientale (Sam.) Juzep: a review

ETHNOPHARMACOLOGICAL RELEVANCE

Rhizoma alismatis (simplified as RA, "Zexie" in Chinese, ) is a well-known natural medicine with long history in Chinese medicine. As a traditional medicine in China, RA is an important part of many prescriptions and has been commonly used for treating a wide range of ailments related to dysuria, edema, nephropathy, hyperlipidaemia, diabetes, inflammation as well as tumor in clinical applications. Based on scientific literatures, the present paper aims to provide comprehensive and up-to date information about the traditional uses, phytochemistry, pharmacology, toxicology and quality control of RA as well as critical analysis of the research. The review will provide a new foundation and direction for the further studies of RA.

MATERIALS AND METHODS

All available information about RA was supplied by library database and electronic search (ScienceDirect, Web of Science, Pubmed, Google Scholar, etc.). The different types of useful information were collected and arranged in corresponding part of the paper.

RESULTS

Phytochemical studies showed that the main chemical composition of RA was the terpenoid including sesquiterpene, diterpene and triterpene. The crude extracts and isolated compounds from RA showed diverse pharmacological activities including diuretic, nephroprotective, anti-hyperlipidemic, anti-atherosclerotic, anti-cancer, anti-inflammatory and anti-oxidative activities. However, high-dose or long-term use of RA can lead to water-electrolyte imbalance, bloody urine, acidosis and even hepatotoxicity or nephrotoxicity, which have been proven by several studies.

CONCLUSIONS

Pharmacological researches show RA possessing various bioactivities including diuresis, nephroprotective effect, anti-hyperlipidemia, etc. However, more bioactive components especially diuretic and nephroprotective compounds need to be isolated and identified, and more rigorous researches on action mechanisms are required. More experiments in vitro or in vivo and clinical studies are encouraged to clarify correlation between traditional uses and modern applications, and the toxicity need to be further and precisely explored. In addition, a standardized fingerprint for RA is indispensable and emergent. These achievements will further expand to therapeutic potential and usage of RA and provide a powerful support for clinical use.

Protostane and fusidane triterpenes: a mini-review

Protostane triterpenes belong to a group of tetracyclic triterpene that exhibit unique structural characteristics. Their natural distribution is primarily limited to the genus Alisma of the Alismataceae family, but they have also been occasionally found in other plant genera such as Lobelia, Garcinia, and Leucas. To date, there are 59 known protostane structures. Many of them have been reported to possess biological properties such as improving lipotropism, hepatoprotection, anti-viral activity against hepatitis B and HIV-I virus, anti-cancer activity, as well as reversal of multidrug resistance in cancer cells. On the other hand, fusidanes are fungal products characterized by 29-nor protostane structures. They possess antibiotic properties against staphylococci, including the methicillin-resistant Staphylococcus aureus (MRSA). Fusidic acid is a representative member which has found clinical applications. This review covers plant sources of the protostanes, their structure elucidation, characteristic structural and spectral properties, as well as biological activities. The fungal sources, structural features, biological activities of fusidanes are also covered in this review. Additionally, the biogenesis of these two types of triterpenes is discussed and a refined pathway is proposed.

Ethanol extract of Alismatis Rhizoma reduces acute lung inflammation by suppressing NF-κB and activating Nrf2

ETHNOPHARMACOLOGICAL RELEVANCE

The tuber of Alisma orientale Juzepzuk, a medicinal herb that has been used for the treatment of various disorders in Korea, has an anti-inflammatory effect. Here, we investigated a possible underlying mechanism and a protective effect on acute lung injury (ALI).

MATERIALS AND METHODS

Alisma orientale tuber was extracted in 80% ethanol and dried. The powder of the ethanol extract of Alisma orientale tuber (EEAO) was dissolved in PBS. The effect of EEAO on NF-κB and Nrf2 activities was analyzed with RAW 264.7 cells. The effect of EEAO on lung inflammation was determined by histologic and molecular biological analyses of the lung tissue of C57BL/6 mice that were gavaged once a day with 0.3 or 1.2 g/kg of EEAO for 14 days, prior to an intranasal administration of LPS (0.01 g/kg) for inducing ALI.

RESULTS

EEAO pre-treatment of RAW 264.7 cells suppressed NF-κB activity and the expression of its dependent genes including COX-2, IL-1β and iNOS. Similar treatment enhanced Nrf2 activity and the expression of Nrf2-regulated genes including NQO-1, HO-1 and GCLC. LPS instillation induced acute neutrophilic lung inflammation, which was significantly suppressed by pre-treatment with EEAO. Analysis of the lungs revealed that EEAO pre-treatment induced the expression of Nrf2-regulated genes, with concomitant down-regulation of inflammatory gene expression.

CONCLUSIONS

EEAO attenuated lung inflammation in LPS-induced ALI mice, which was associated with differential regulation of NF-κB and Nrf2 activities. We suggest that EEAO can be developed as a potential therapeutics for the treatment of ALI.

Qualitative and quantitative analysis of the major constituents in Chinese medicinal preparation Dan-Lou tablet by ultra high performance liquid chromatography/diode-array detector/quadrupole time-of-flight tandem mass spectrometry

A rapid ultra high performance liquid chromatography/diode-array detector/quadrupole time-of-flight tandem mass spectrometry (UPLC-DAD-QTOF) method and a ultra high performance liquid chromatography coupled with diode-array detector (UPLC-DAD) method were developed for qualitative and quantitative analyses of the major chemical constituents in Dan-Lou tablet. Sixty-eight compounds including flavonoids, phenolic acids, tanshinones, protostane triterpenoids, lactones, and paeoniflorins were unambiguously or tentatively identified by comparing their retention times and accurate mass measurement in 40min with references or literature data. Among them, 19 compounds: gallic acid, danshensu, 5-hydroxymethyl-2-furaldehyde, 3'-hydroxy puerarin, puerarin, 3'-methoxy puerarin, mirificin, daidzin, paeoniflorin, calycosin-7-O-β-D-glucoside, naringin, genistin, rosmarinic acid, salvianolic acid B, salvianolic acid A, formononetin, calycosin, cryptotanshinone and tanshinone IIA were further quantified in 30min as marker substances. It was found that the calibration curves for all analytes showed good linearity (R(2)>0.9997) within the test ranges. The overall limits of detection (LODs) and limits of quantification (LOQs) were 0.0073-0.34μg/mL and 0.022-1.04μg/mL, respectively. The relative standard deviations (RSDs) for intra- and inter-day precisions were below 1.90% and 2.85%, respectively. The results of repeatability were less than 2.74%. The sample was stable for at least 48h. The mean recovery rates ranged from 95.5% to 105% with the relative standard deviations (RSDs) less than 2.96%. The results showed that the developed quantitative method was linear, sensitive, and precise for quality control of Dan-Lou tablet.

cis-Aconitic Anhydride Ethyl Ester and Phenolic Compounds from the Seeds of Alisma orientale

From the seeds of Alisma orientale, cis-aconitic anhydride ethyl ester and cis-2,4,5-trihydroxycinnamic acid were isolated, together with nine known phenolic compounds and a megastigmane sesquiterpene. All compounds are reported for the first time from Alisma species.

Cytotoxic xanthone constituents of the stem bark of Garcinia mangostana (mangosteen)

Bioassay-guided fractionation of a chloroform-soluble extract of Garcinia mangostana stem bark, using the HT-29 human colon cancer cell line and an enzyme-based ELISA NF-kappaB assay, led to the isolation of a new xanthone, 11-hydroxy-3-O-methyl-1-isomangostin (1). The structure of 1 was elucidated by spectroscopic data analysis. In addition, 10 other known compounds, 11-hydroxy-1-isomangostin (2), 11alpha-mangostanin (3), 3-isomangostin (4), alpha-mangostin (5), beta-mangostin (6), garcinone D (7), 9-hydroxycalabaxanthone (8), 8-deoxygartanin (9), gartanin (10), and cratoxyxanthone (11), were isolated. Compounds 4-8 exhibited cytotoxicity against the HT-29 cell line with ED50 values of 4.9, 1.7, 1.7, 2.3, and 9.1 microM, respectively. In an ELISA NF-kappaB assay, compounds 5-7, 9, and 10 inhibited p65 activation with IC50 values of 15.9, 12.1, 3.2, 11.3, and 19.0 microM, respectively, and 6 showed p50 inhibitory activity with an IC50 value of 7.5 microM. Alpha-mangostin (5) was further tested in an in vivo hollow fiber assay, using HT-29, LNCaP, and MCF-7 cells, but it was found to be inactive at the highest dose tested (20 mg/kg).